Merge tag 'riscv-for-linus-4.15-arch-v9-premerge' of...

Merge tag 'riscv-for-linus-4.15-arch-v9-premerge' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux

Pull RISC-V architecture support from Palmer Dabbelt:
 "This contains the core RISC-V Linux port, which has been through nine
  rounds of review on various mailing lists. The port is not complete:
  there's some cleanup patches moving through the review process, a
  whole bunch of drivers that need some work, and a lot of feature
  additions that will be needed.

  The patches contained in this tag have been through nine rounds of
  review on the various mailing lists. I have some outstanding cleanup
  patches, but since there's been so much review on these patches I
  thought it would be best to submit them as-is and then submit explicit
  cleanup patches so everyone can review them. This first patch set is
  big enough that it's a bit of a pain to constantly rewrite, and it's
  caused a few headaches with various contributors.

  The port is definately a work in progress. While what's there builds
  and boots with 4.14, it's a bit hard to actually see anything happen
  because there are no device drivers yet. I maintain a staging branch
  that contains all the device drivers and cleanup that actually works,
  but those patches won't all be ready for a while. I'd like to get what
  we currently have into your tree so everyone can start working from a
  single base -- of particular importance is allowing the glibc
  upstreaming process to proceed so we can sort out any possibly
  lingering user-visible ABI problems we might have.

  Copied below is the ChangeLog that contains the history of this patch
  set:

   (v9) As per suggestions on our v8 patch set, I've split the core
        architecture code out from our drivers and would like to submit
        this patch set to be included into linux-next, with the goal
        being to be merged in during the next merge window. This patch
        set is based on 4.14-rc2, but if it's better to have it based on
        something else then I can change it around.

        This patch set contains just the core arch code for RISC-V, so
        while it builds an nominally boots, you can't print or take an
        interrupt so it's not that useful. If you're looking to actually
        boot a system it would probably be better to use the full patch
        set listed below.

        We've collected a handful of tags from reviewers, and the
        remainder of the patch set only got minimal feedback last time.
        Here's what changed:

         - We now use the device tree to initialize the timer driver so
           it's less tighly coupled with the arch port.

         - I cleaned up the defconfigs -- there's actually now just one,
           and it's empty. For now I think we're OK with what the kernel
           sets as defaults, but I anticipate we'll begin to expand this
           as people start to use the port more.

         - The VDSO symbols version is sane.

         - We WFI while spinning in the boot loop.

         - A handful of comments have been added.

        While there are still a handful of FIXMEs in this patch set,
        we've started to get enough interest from various users and
        contributors that maintaining an out of tree patch set is
        starting to become a big burden. Hopefully the patches are good
        enough to merge now, which will at least get everyone working in
        a more reasonable manner as we clean up the remaining issues.

   (v8) I know it may not be the ideal time to submit a patch set right
        now, as it's the middle of the merge window, but things have
        calmed down quite a bit in the last month so I thought it would
        be good to get everyone on the same page. There's been a handful
        of changes since the last patch set, but most of them are fairly
        minor:

         - We changed PAGE_OFFSET to allowing mapping more physical
           memory on 64-bit systems. This is user configurable, as it
           triggers a different code model that generates slightly less
           efficient code.

         - The device tree binding documentation is back, I'd managed to
           lose it at some point.

         - We now pass the atomic64 test suite

         - The SBI timer driver has been refactored.

   (v7) It's been a while since my last patch set, but the changes han
        been fairly minimal:

         - The PCI cleanup patches have been dropped, we'll do them as a
           separate patch set later.

         - We've the Kconfig entries from CONFIG_ISA_* to
           CONFIG_RISCV_ISA_*, to make grep easier.

         - There have been a handful of memory model related tweaks in
           I/O land, particularly relating the PCI and the upcoming
           platform specification. There are significant comments in the
           relevant files. This is still a WIP, but I think we're close
           to getting as good as we're going to get until we end up with
           some more specifications.

   (v6) As it's been only a day since the v5 patch set, the changes are
        pretty minimal:

         - The patch set is now based on linux-next/master, which I
           believe is a better base now that we're getting closer to
           upstream.

         - EARLY_PRINTK is no longer an option. Since the SBI console is
           reasonable, there's no penalty to enabling it (and thus no
           benefit to disabling it).

         - The mmap syscalls were refactored a bit.

   (v5) Things have really started to calm down, so this is fairly
        similar to the v4 patch set. The most interesting changes
        include:

         - We've moved back to a single patch set.

         - SMP support has been fixed, I was accidentally running on a
           non-SMP configuration. There were various mistakes all over
           the tree as a result of this.

         - The cmpxchg syscalls have been removed, as they were deemed a
           bad idea. As a result, RISC-V Linux systems mandate the A
           extension. The corresponding Kconfig entry to enable builds
           on non-A systems has been removed.

         - A few more atomic fixes: mostly fence changes, but those
           resulted in a handful of additional macros that were no
           longer necessary.

         - riscv_early_sie has been removed.

   (v4) There have only been a few changes since the v3 patch set:

         - The cmpxchg64 syscall is no longer enabled on 32-bit systems.
           It's not possible to provide this on SMP systems, and it's
           not necessary as glibc knows not to call it.

         - We provide a ELF_HWCAP so users can determine the ISA of the
           machine the kernel is running on.

         - The multi-line comments are in a better form.

         - There were a handful of headers that could be replaced with
           the asm-generic versions, and a few unnecessary definitions.

         - We no longer use printk, but instead use pr_*.

         - A few Kconfig and defconfig entries have been cleaned up.

   (v3) A highlight of the changes since the v2 patch set includes:

         - We've split out all our drivers into separate patch sets,
           which I've already sent out to the relevant maintainers. I
           haven't included those patches in this patch set, but some of
           them are necessary to build our port.

         - The patch set is now split up differently: rather than being
           split per directory it is split per topic. Hopefully this
           will make it easier to review the port on the mailing list.
           The split is a bit rough, so you probably still want to look
           at the patch set as a whole.

         - atomic.h has been completely rewritten and is hopefully now
           correct. I've attempted to sanitize the various other memory
           model related code as well, and I think it should all be sane
           now aside from a handful of FIXMEs commented in the code.

         - We've changed the cmpexchg syscall to always exist and to not
           be multiplexed. There is also a VDSO entry for compare and
           exchange, which allows kernels with the A extension to
           execute user code without the A extension reasonably fast.

         - Our user-visible register state now contains enough space for
           the Q extension for 128-bit floating point, as well as a few
           words to allow extensibility to future ISA extensions like
           the eventual V extension for vectors.

         - A handful of driver cleanups, but these have been split into
           separate patch sets now so I won't duplicate them here.

   (v2) A highlight of the changes since the v1 patch set includes:

         - We've split out our drivers into the right places, which
           means now there's a lot more patches. I'll be submitting
           these patches to various subsystem maintainers and including
           them in any future RISC-V patch sets until they've been
           merged.

         - The SBI console driver has been completely rewritten to use
           the HVC helpers and is now significantly smaller.

         - We've begun to use weaker barriers as opposed to just the big
           "fence". There's still some work to do here, specifically:
            - We need fences in the relaxed MMIO functions.
            - The non-relaxed MMIO functions are missing R/W bits on their fences.
            - Many AMOs need the aq and rl bits set.

         - We now have thread_info in task_struct. As a result, sscratch
           now contains TP instead of SP. This was necessary because
           thread_info is no longer on the stack.

         - A few shared routines have been added that we use instead of
           creating another arch copy"
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

* tag 'riscv-for-linus-4.15-arch-v9-premerge' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux:
  RISC-V: Build Infrastructure
  RISC-V: User-facing API
  RISC-V: Paging and MMU
  RISC-V: Device, timer, IRQs, and the SBI
  RISC-V: Task implementation
  RISC-V: ELF and module implementation
  RISC-V: Generic library routines and assembly
  RISC-V: Atomic and Locking Code
  RISC-V: Init and Halt Code
  dt-bindings: RISC-V CPU Bindings
  lib: Add shared copies of some GCC library routines
  MAINTAINERS: Add RISC-V

Documentation/devicetree/bindings/riscv/cpus.txt

+===================
+RISC-V CPU Bindings
+===================
+
+The device tree allows to describe the layout of CPUs in a system through
+the "cpus" node, which in turn contains a number of subnodes (ie "cpu")
+defining properties for every cpu.
+
+Bindings for CPU nodes follow the Devicetree Specification, available from:
+
+https://www.devicetree.org/specifications/
+
+with updates for 32-bit and 64-bit RISC-V systems provided in this document.
+
+===========
+Terminology
+===========
+
+This document uses some terminology common to the RISC-V community that is not
+widely used, the definitions of which are listed here:
+
+* hart: A hardware execution context, which contains all the state mandated by
+  the RISC-V ISA: a PC and some registers.  This terminology is designed to
+  disambiguate software's view of execution contexts from any particular
+  microarchitectural implementation strategy.  For example, my Intel laptop is
+  described as having one socket with two cores, each of which has two hyper
+  threads.  Therefore this system has four harts.
+
+=====================================
+cpus and cpu node bindings definition
+=====================================
+
+The RISC-V architecture, in accordance with the Devicetree Specification,
+requires the cpus and cpu nodes to be present and contain the properties
+described below.
+
+- cpus node
+
+        Description: Container of cpu nodes
+
+        The node name must be "cpus".
+
+        A cpus node must define the following properties:
+
+        - #address-cells
+                Usage: required
+                Value type: <u32>
+                Definition: must be set to 1
+        - #size-cells
+                Usage: required
+                Value type: <u32>
+                Definition: must be set to 0
+
+- cpu node
+
+        Description: Describes a hart context
+
+        PROPERTIES
+
+        - device_type
+                Usage: required
+                Value type: <string>
+                Definition: must be "cpu"
+        - reg
+                Usage: required
+                Value type: <u32>
+                Definition: The hart ID of this CPU node
+        - compatible:
+                Usage: required
+                Value type: <stringlist>
+                Definition: must contain "riscv", may contain one of
+                            "sifive,rocket0"
+        - mmu-type:
+                Usage: optional
+                Value type: <string>
+                Definition: Specifies the CPU's MMU type.  Possible values are
+                            "riscv,sv32"
+                            "riscv,sv39"
+                            "riscv,sv48"
+        - riscv,isa:
+                Usage: required
+                Value type: <string>
+                Definition: Contains the RISC-V ISA string of this hart.  These
+                            ISA strings are defined by the RISC-V ISA manual.
+
+Example: SiFive Freedom U540G Development Kit
+---------------------------------------------
+
+This system contains two harts: a hart marked as disabled that's used for
+low-level system tasks and should be ignored by Linux, and a second hart that
+Linux is allowed to run on.
+
+        cpus {
+                #address-cells = <1>;
+                #size-cells = <0>;
+                timebase-frequency = <1000000>;
+                cpu@0 {
+                        clock-frequency = <1600000000>;
+                        compatible = "sifive,rocket0", "riscv";
+                        device_type = "cpu";
+                        i-cache-block-size = <64>;
+                        i-cache-sets = <128>;
+                        i-cache-size = <16384>;
+                        next-level-cache = <&L15 &L0>;
+                        reg = <0>;
+                        riscv,isa = "rv64imac";
+                        status = "disabled";
+                        L10: interrupt-controller {
+                                #interrupt-cells = <1>;
+                                compatible = "riscv,cpu-intc";
+                                interrupt-controller;
+                        };
+                };
+                cpu@1 {
+                        clock-frequency = <1600000000>;
+                        compatible = "sifive,rocket0", "riscv";
+                        d-cache-block-size = <64>;
+                        d-cache-sets = <64>;
+                        d-cache-size = <32768>;
+                        d-tlb-sets = <1>;
+                        d-tlb-size = <32>;
+                        device_type = "cpu";
+                        i-cache-block-size = <64>;
+                        i-cache-sets = <64>;
+                        i-cache-size = <32768>;
+                        i-tlb-sets = <1>;
+                        i-tlb-size = <32>;
+                        mmu-type = "riscv,sv39";
+                        next-level-cache = <&L15 &L0>;
+                        reg = <1>;
+                        riscv,isa = "rv64imafdc";
+                        status = "okay";
+                        tlb-split;
+                        L13: interrupt-controller {
+                                #interrupt-cells = <1>;
+                                compatible = "riscv,cpu-intc";
+                                interrupt-controller;
+                        };
+                };
+        };
+
+Example: Spike ISA Simulator with 1 Hart
+----------------------------------------
+
+This device tree matches the Spike ISA golden model as run with `spike -p1`.
+
+        cpus {
+                cpu@0 {
+                        device_type = "cpu";
+                        reg = <0x00000000>;
+                        status = "okay";
+                        compatible = "riscv";
+                        riscv,isa = "rv64imafdc";
+                        mmu-type = "riscv,sv48";
+                        clock-frequency = <0x3b9aca00>;
+                        interrupt-controller {
+                                #interrupt-cells = <0x00000001>;
+                                interrupt-controller;
+                                compatible = "riscv,cpu-intc";
+                        }
+                }
+        }

MAINTAINERS

@@ -11534,6 +11534,16 @@ S:	Maintained
 F:	drivers/mtd/nand/r852.c
 F:	drivers/mtd/nand/r852.h
 
+RISC-V ARCHITECTURE
+M:	Palmer Dabbelt <palmer@sifive.com>
+M:	Albert Ou <albert@sifive.com>
+L:	patches@groups.riscv.org
+T:	git https://github.com/riscv/riscv-linux
+S:	Supported
+F:	arch/riscv/
+K:	riscv
+N:	riscv
+
 ROCCAT DRIVERS
 M:	Stefan Achatz <erazor_de@users.sourceforge.net>
 W:	http://sourceforge.net/projects/roccat/

Makefile

@@ -226,7 +226,8 @@ SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
 				  -e s/arm.*/arm/ -e s/sa110/arm/ \
 				  -e s/s390x/s390/ -e s/parisc64/parisc/ \
 				  -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
-				  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
+				  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
+				  -e s/riscv.*/riscv/)
 
 # Cross compiling and selecting different set of gcc/bin-utils
 # ---------------------------------------------------------------------------

arch/riscv/Kconfig

+#
+# For a description of the syntax of this configuration file,
+# see Documentation/kbuild/kconfig-language.txt.
+#
+
+config RISCV
+	def_bool y
+	select OF
+	select OF_EARLY_FLATTREE
+	select OF_IRQ
+	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
+	select ARCH_WANT_FRAME_POINTERS
+	select CLONE_BACKWARDS
+	select COMMON_CLK
+	select GENERIC_CLOCKEVENTS
+	select GENERIC_CPU_DEVICES
+	select GENERIC_IRQ_SHOW
+	select GENERIC_PCI_IOMAP
+	select GENERIC_STRNCPY_FROM_USER
+	select GENERIC_STRNLEN_USER
+	select GENERIC_SMP_IDLE_THREAD
+	select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A
+	select ARCH_WANT_OPTIONAL_GPIOLIB
+	select HAVE_MEMBLOCK
+	select HAVE_DMA_API_DEBUG
+	select HAVE_DMA_CONTIGUOUS
+	select HAVE_GENERIC_DMA_COHERENT
+	select IRQ_DOMAIN
+	select NO_BOOTMEM
+	select RISCV_ISA_A if SMP
+	select SPARSE_IRQ
+	select SYSCTL_EXCEPTION_TRACE
+	select HAVE_ARCH_TRACEHOOK
+	select MODULES_USE_ELF_RELA if MODULES
+	select THREAD_INFO_IN_TASK
+	select RISCV_IRQ_INTC
+	select RISCV_TIMER
+
+config MMU
+	def_bool y
+
+# even on 32-bit, physical (and DMA) addresses are > 32-bits
+config ARCH_PHYS_ADDR_T_64BIT
+	def_bool y
+
+config ARCH_DMA_ADDR_T_64BIT
+	def_bool y
+
+config PAGE_OFFSET
+	hex
+	default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
+	default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
+	default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
+
+config STACKTRACE_SUPPORT
+	def_bool y
+
+config RWSEM_GENERIC_SPINLOCK
+	def_bool y
+
+config GENERIC_BUG
+	def_bool y
+	depends on BUG
+	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
+
+config GENERIC_BUG_RELATIVE_POINTERS
+	bool
+
+config GENERIC_CALIBRATE_DELAY
+	def_bool y
+
+config GENERIC_CSUM
+	def_bool y
+
+config GENERIC_HWEIGHT
+	def_bool y
+
+config PGTABLE_LEVELS
+	int
+	default 3 if 64BIT
+	default 2
+
+config HAVE_KPROBES
+	def_bool n
+
+config DMA_NOOP_OPS
+	def_bool y
+
+menu "Platform type"
+
+choice
+	prompt "Base ISA"
+	default ARCH_RV64I
+	help
+	  This selects the base ISA that this kernel will traget and must match
+	  the target platform.
+
+config ARCH_RV32I
+	bool "RV32I"
+	select CPU_SUPPORTS_32BIT_KERNEL
+	select 32BIT
+	select GENERIC_ASHLDI3
+	select GENERIC_ASHRDI3
+	select GENERIC_LSHRDI3
+
+config ARCH_RV64I
+	bool "RV64I"
+	select CPU_SUPPORTS_64BIT_KERNEL
+	select 64BIT
+
+endchoice
+
+# We must be able to map all physical memory into the kernel, but the compiler
+# is still a bit more efficient when generating code if it's setup in a manner
+# such that it can only map 2GiB of memory.
+choice
+	prompt "Kernel Code Model"
+	default CMODEL_MEDLOW if 32BIT
+	default CMODEL_MEDANY if 64BIT
+
+	config CMODEL_MEDLOW
+		bool "medium low code model"
+	config CMODEL_MEDANY
+		bool "medium any code model"
+endchoice
+
+choice
+	prompt "Maximum Physical Memory"
+	default MAXPHYSMEM_2GB if 32BIT
+	default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
+	default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
+
+	config MAXPHYSMEM_2GB
+		bool "2GiB"
+	config MAXPHYSMEM_128GB
+		depends on 64BIT && CMODEL_MEDANY
+		bool "128GiB"
+endchoice
+
+
+config SMP
+	bool "Symmetric Multi-Processing"
+	help
+	  This enables support for systems with more than one CPU.  If
+	  you say N here, the kernel will run on single and
+	  multiprocessor machines, but will use only one CPU of a
+	  multiprocessor machine. If you say Y here, the kernel will run
+	  on many, but not all, single processor machines. On a single
+	  processor machine, the kernel will run faster if you say N
+	  here.
+
+	  If you don't know what to do here, say N.
+
+config NR_CPUS
+	int "Maximum number of CPUs (2-32)"
+	range 2 32
+	depends on SMP
+	default "8"
+
+config CPU_SUPPORTS_32BIT_KERNEL
+	bool
+config CPU_SUPPORTS_64BIT_KERNEL
+	bool
+
+choice
+	prompt "CPU Tuning"
+	default TUNE_GENERIC
+
+config TUNE_GENERIC
+	bool "generic"
+
+endchoice
+
+config RISCV_ISA_C
+	bool "Emit compressed instructions when building Linux"
+	default y
+	help
+	   Adds "C" to the ISA subsets that the toolchain is allowed to emit
+	   when building Linux, which results in compressed instructions in the
+	   Linux binary.
+
+	   If you don't know what to do here, say Y.
+
+config RISCV_ISA_A
+	def_bool y
+
+endmenu
+
+menu "Kernel type"
+
+choice
+	prompt "Kernel code model"
+	default 64BIT
+
+config 32BIT
+	bool "32-bit kernel"
+	depends on CPU_SUPPORTS_32BIT_KERNEL
+	help
+	  Select this option to build a 32-bit kernel.
+
+config 64BIT
+	bool "64-bit kernel"
+	depends on CPU_SUPPORTS_64BIT_KERNEL
+	help
+	  Select this option to build a 64-bit kernel.
+
+endchoice
+
+source "mm/Kconfig"
+
+source "kernel/Kconfig.preempt"
+
+source "kernel/Kconfig.hz"
+
+endmenu
+
+menu "Bus support"
+
+config PCI
+	bool "PCI support"
+	select PCI_MSI
+	help
+	  This feature enables support for PCI bus system. If you say Y
+	  here, the kernel will include drivers and infrastructure code
+	  to support PCI bus devices.
+
+	  If you don't know what to do here, say Y.
+
+config PCI_DOMAINS
+	def_bool PCI
+
+config PCI_DOMAINS_GENERIC
+	def_bool PCI
+
+source "drivers/pci/Kconfig"
+
+endmenu
+
+source "init/Kconfig"
+
+source "kernel/Kconfig.freezer"
+
+menu "Executable file formats"
+
+source "fs/Kconfig.binfmt"
+
+endmenu
+
+menu "Power management options"
+
+source kernel/power/Kconfig
+
+endmenu
+
+source "net/Kconfig"
+
+source "drivers/Kconfig"
+
+source "fs/Kconfig"
+
+menu "Kernel hacking"
+
+config CMDLINE_BOOL
+	bool "Built-in kernel command line"
+	help
+	  For most platforms, it is firmware or second stage bootloader
+	  that by default specifies the kernel command line options.
+	  However, it might be necessary or advantageous to either override
+	  the default kernel command line or add a few extra options to it.
+	  For such cases, this option allows hardcoding command line options
+	  directly into the kernel.
+
+	  For that, choose 'Y' here and fill in the extra boot parameters
+	  in CONFIG_CMDLINE.
+
+	  The built-in options will be concatenated to the default command
+	  line if CMDLINE_OVERRIDE is set to 'N'. Otherwise, the default
+	  command line will be ignored and replaced by the built-in string.
+
+config CMDLINE
+	string "Built-in kernel command string"
+	depends on CMDLINE_BOOL
+	default ""
+	help
+	  Supply command-line options at build time by entering them here.
+
+config CMDLINE_OVERRIDE
+	bool "Built-in command line overrides bootloader arguments"
+	depends on CMDLINE_BOOL
+	help
+	  Set this option to 'Y' to have the kernel ignore the bootloader
+	  or firmware command line.  Instead, the built-in command line
+	  will be used exclusively.
+
+	  If you don't know what to do here, say N.
+
+config EARLY_PRINTK
+	def_bool y
+
+source "lib/Kconfig.debug"
+
+config CMDLINE_BOOL
+	bool
+endmenu
+
+source "security/Kconfig"
+
+source "crypto/Kconfig"
+
+source "lib/Kconfig"

arch/riscv/Makefile

+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies. Remember to do have actions
+# for "archclean" and "archdep" for cleaning up and making dependencies for
+# this architecture
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+
+LDFLAGS         :=
+OBJCOPYFLAGS    := -O binary
+LDFLAGS_vmlinux :=
+KBUILD_AFLAGS_MODULE += -fPIC
+KBUILD_CFLAGS_MODULE += -fPIC
+
+KBUILD_DEFCONFIG = defconfig
+
+export BITS
+ifeq ($(CONFIG_ARCH_RV64I),y)
+	BITS := 64
+	UTS_MACHINE := riscv64
+
+	KBUILD_CFLAGS += -mabi=lp64
+	KBUILD_AFLAGS += -mabi=lp64
+	KBUILD_MARCH = rv64im
+	LDFLAGS += -melf64lriscv
+else
+	BITS := 32
+	UTS_MACHINE := riscv32
+
+	KBUILD_CFLAGS += -mabi=ilp32
+	KBUILD_AFLAGS += -mabi=ilp32
+	KBUILD_MARCH = rv32im
+	LDFLAGS += -melf32lriscv
+endif
+
+KBUILD_CFLAGS += -Wall
+
+ifeq ($(CONFIG_RISCV_ISA_A),y)
+	KBUILD_ARCH_A = a
+endif
+ifeq ($(CONFIG_RISCV_ISA_C),y)
+	KBUILD_ARCH_C = c
+endif
+
+KBUILD_AFLAGS += -march=$(KBUILD_MARCH)$(KBUILD_ARCH_A)fd$(KBUILD_ARCH_C)
+
+KBUILD_CFLAGS += -march=$(KBUILD_MARCH)$(KBUILD_ARCH_A)$(KBUILD_ARCH_C)
+KBUILD_CFLAGS += -mno-save-restore
+KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)
+
+ifeq ($(CONFIG_CMODEL_MEDLOW),y)
+	KBUILD_CFLAGS += -mcmodel=medlow
+endif
+ifeq ($(CONFIG_CMODEL_MEDANY),y)
+	KBUILD_CFLAGS += -mcmodel=medany
+endif
+
+# GCC versions that support the "-mstrict-align" option default to allowing
+# unaligned accesses.  While unaligned accesses are explicitly allowed in the
+# RISC-V ISA, they're emulated by machine mode traps on all extant
+# architectures.  It's faster to have GCC emit only aligned accesses.
+KBUILD_CFLAGS += $(call cc-option,-mstrict-align)
+
+head-y := arch/riscv/kernel/head.o
+
+core-y += arch/riscv/kernel/ arch/riscv/mm/
+
+libs-y += arch/riscv/lib/
+
+all: vmlinux

arch/riscv/include/asm/Kbuild

+generic-y += bugs.h
+generic-y += cacheflush.h
+generic-y += checksum.h
+generic-y += clkdev.h
+generic-y += cputime.h
+generic-y += device.h
+generic-y += div64.h
+generic-y += dma.h
+generic-y += dma-contiguous.h
+generic-y += emergency-restart.h
+generic-y += errno.h
+generic-y += exec.h
+generic-y += fb.h
+generic-y += fcntl.h
+generic-y += ftrace.h
+generic-y += futex.h
+generic-y += hardirq.h
+generic-y += hash.h
+generic-y += hw_irq.h
+generic-y += ioctl.h
+generic-y += ioctls.h
+generic-y += ipcbuf.h
+generic-y += irq_regs.h
+generic-y += irq_work.h
+generic-y += kdebug.h
+generic-y += kmap_types.h
+generic-y += kvm_para.h
+generic-y += local.h
+generic-y += mm-arch-hooks.h
+generic-y += mman.h
+generic-y += module.h
+generic-y += msgbuf.h
+generic-y += mutex.h
+generic-y += param.h
+generic-y += percpu.h
+generic-y += poll.h
+generic-y += posix_types.h
+generic-y += preempt.h
+generic-y += resource.h
+generic-y += scatterlist.h
+generic-y += sections.h
+generic-y += sembuf.h
+generic-y += setup.h
+generic-y += shmbuf.h
+generic-y += shmparam.h
+generic-y += signal.h
+generic-y += socket.h
+generic-y += sockios.h
+generic-y += stat.h
+generic-y += statfs.h
+generic-y += swab.h
+generic-y += termbits.h
+generic-y += termios.h
+generic-y += topology.h
+generic-y += trace_clock.h
+generic-y += types.h
+generic-y += unaligned.h
+generic-y += user.h
+generic-y += vga.h
+generic-y += vmlinux.lds.h
+generic-y += xor.h

arch/riscv/include/asm/asm-offsets.h

+#include <generated/asm-offsets.h>

arch/riscv/include/asm/asm.h

+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_ASM_H
+#define _ASM_RISCV_ASM_H
+
+#ifdef __ASSEMBLY__
+#define __ASM_STR(x)	x
+#else
+#define __ASM_STR(x)	#x
+#endif
+
+#if __riscv_xlen == 64
+#define __REG_SEL(a, b)	__ASM_STR(a)
+#elif __riscv_xlen == 32
+#define __REG_SEL(a, b)	__ASM_STR(b)
+#else
+#error "Unexpected __riscv_xlen"
+#endif
+
+#define REG_L		__REG_SEL(ld, lw)
+#define REG_S		__REG_SEL(sd, sw)
+#define SZREG		__REG_SEL(8, 4)
+#define LGREG		__REG_SEL(3, 2)
+
+#if __SIZEOF_POINTER__ == 8
+#ifdef __ASSEMBLY__
+#define RISCV_PTR		.dword
+#define RISCV_SZPTR		8
+#define RISCV_LGPTR		3
+#else
+#define RISCV_PTR		".dword"
+#define RISCV_SZPTR		"8"
+#define RISCV_LGPTR		"3"
+#endif
+#elif __SIZEOF_POINTER__ == 4
+#ifdef __ASSEMBLY__
+#define RISCV_PTR		.word
+#define RISCV_SZPTR		4
+#define RISCV_LGPTR		2
+#else
+#define RISCV_PTR		".word"
+#define RISCV_SZPTR		"4"
+#define RISCV_LGPTR		"2"
+#endif
+#else
+#error "Unexpected __SIZEOF_POINTER__"
+#endif
+
+#if (__SIZEOF_INT__ == 4)
+#define INT		__ASM_STR(.word)
+#define SZINT		__ASM_STR(4)
+#define LGINT		__ASM_STR(2)
+#else
+#error "Unexpected __SIZEOF_INT__"
+#endif
+
+#if (__SIZEOF_SHORT__ == 2)
+#define SHORT		__ASM_STR(.half)
+#define SZSHORT		__ASM_STR(2)
+#define LGSHORT		__ASM_STR(1)
+#else
+#error "Unexpected __SIZEOF_SHORT__"
+#endif
+
+#endif /* _ASM_RISCV_ASM_H */

arch/riscv/include/asm/barrier.h

+/*
+ * Based on arch/arm/include/asm/barrier.h
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2013 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _ASM_RISCV_BARRIER_H
+#define _ASM_RISCV_BARRIER_H
+
+#ifndef __ASSEMBLY__
+
+#define nop()		__asm__ __volatile__ ("nop")
+
+#define RISCV_FENCE(p, s) \
+	__asm__ __volatile__ ("fence " #p "," #s : : : "memory")
+
+/* These barriers need to enforce ordering on both devices or memory. */
+#define mb()		RISCV_FENCE(iorw,iorw)
+#define rmb()		RISCV_FENCE(ir,ir)
+#define wmb()		RISCV_FENCE(ow,ow)
+
+/* These barriers do not need to enforce ordering on devices, just memory. */
+#define smp_mb()	RISCV_FENCE(rw,rw)
+#define smp_rmb()	RISCV_FENCE(r,r)
+#define smp_wmb()	RISCV_FENCE(w,w)
+
+/*
+ * These fences exist to enforce ordering around the relaxed AMOs.  The
+ * documentation defines that
+ * "
+ *     atomic_fetch_add();
+ *   is equivalent to:
+ *     smp_mb__before_atomic();
+ *     atomic_fetch_add_relaxed();
+ *     smp_mb__after_atomic();
+ * "
+ * So we emit full fences on both sides.
+ */
+#define __smb_mb__before_atomic()	smp_mb()
+#define __smb_mb__after_atomic()	smp_mb()
+
+/*
+ * These barriers prevent accesses performed outside a spinlock from being moved
+ * inside a spinlock.  Since RISC-V sets the aq/rl bits on our spinlock only
+ * enforce release consistency, we need full fences here.
+ */
+#define smb_mb__before_spinlock()	smp_mb()
+#define smb_mb__after_spinlock()	smp_mb()
+
+#include <asm-generic/barrier.h>
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_BARRIER_H */

arch/riscv/include/asm/bitops.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_BITOPS_H
+#define _ASM_RISCV_BITOPS_H
+
+#ifndef _LINUX_BITOPS_H
+#error "Only <linux/bitops.h> can be included directly"
+#endif /* _LINUX_BITOPS_H */
+
+#include <linux/compiler.h>
+#include <linux/irqflags.h>
+#include <asm/barrier.h>
+#include <asm/bitsperlong.h>
+
+#ifndef smp_mb__before_clear_bit
+#define smp_mb__before_clear_bit()  smp_mb()
+#define smp_mb__after_clear_bit()   smp_mb()
+#endif /* smp_mb__before_clear_bit */
+
+#include <asm-generic/bitops/__ffs.h>
+#include <asm-generic/bitops/ffz.h>
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/find.h>
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/ffs.h>
+
+#include <asm-generic/bitops/hweight.h>
+
+#if (BITS_PER_LONG == 64)
+#define __AMO(op)	"amo" #op ".d"
+#elif (BITS_PER_LONG == 32)
+#define __AMO(op)	"amo" #op ".w"
+#else
+#error "Unexpected BITS_PER_LONG"
+#endif
+
+#define __test_and_op_bit_ord(op, mod, nr, addr, ord)		\
+({								\
+	unsigned long __res, __mask;				\
+	__mask = BIT_MASK(nr);					\
+	__asm__ __volatile__ (					\
+		__AMO(op) #ord " %0, %2, %1"			\
+		: "=r" (__res), "+A" (addr[BIT_WORD(nr)])	\
+		: "r" (mod(__mask))				\
+		: "memory");					\
+	((__res & __mask) != 0);				\
+})
+
+#define __op_bit_ord(op, mod, nr, addr, ord)			\
+	__asm__ __volatile__ (					\
+		__AMO(op) #ord " zero, %1, %0"			\
+		: "+A" (addr[BIT_WORD(nr)])			\
+		: "r" (mod(BIT_MASK(nr)))			\
+		: "memory");
+
+#define __test_and_op_bit(op, mod, nr, addr) 			\
+	__test_and_op_bit_ord(op, mod, nr, addr, )
+#define __op_bit(op, mod, nr, addr)				\
+	__op_bit_ord(op, mod, nr, addr, )
+
+/* Bitmask modifiers */
+#define __NOP(x)	(x)
+#define __NOT(x)	(~(x))
+
+/**
+ * test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation may be reordered on other architectures than x86.
+ */
+static inline int test_and_set_bit(int nr, volatile unsigned long *addr)
+{
+	return __test_and_op_bit(or, __NOP, nr, addr);
+}
+
+/**
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation can be reordered on other architectures other than x86.
+ */
+static inline int test_and_clear_bit(int nr, volatile unsigned long *addr)
+{
+	return __test_and_op_bit(and, __NOT, nr, addr);
+}
+
+/**
+ * test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_change_bit(int nr, volatile unsigned long *addr)
+{
+	return __test_and_op_bit(xor, __NOP, nr, addr);
+}
+
+/**
+ * set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Note: there are no guarantees that this function will not be reordered
+ * on non x86 architectures, so if you are writing portable code,
+ * make sure not to rely on its reordering guarantees.
+ *
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void set_bit(int nr, volatile unsigned long *addr)
+{
+	__op_bit(or, __NOP, nr, addr);
+}
+
+/**
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * Note: there are no guarantees that this function will not be reordered
+ * on non x86 architectures, so if you are writing portable code,
+ * make sure not to rely on its reordering guarantees.
+ */
+static inline void clear_bit(int nr, volatile unsigned long *addr)
+{
+	__op_bit(and, __NOT, nr, addr);
+}
+
+/**
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * change_bit()  may be reordered on other architectures than x86.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void change_bit(int nr, volatile unsigned long *addr)
+{
+	__op_bit(xor, __NOP, nr, addr);
+}
+
+/**
+ * test_and_set_bit_lock - Set a bit and return its old value, for lock
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and provides acquire barrier semantics.
+ * It can be used to implement bit locks.
+ */
+static inline int test_and_set_bit_lock(
+	unsigned long nr, volatile unsigned long *addr)
+{
+	return __test_and_op_bit_ord(or, __NOP, nr, addr, .aq);
+}
+
+/**
+ * clear_bit_unlock - Clear a bit in memory, for unlock
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This operation is atomic and provides release barrier semantics.
+ */
+static inline void clear_bit_unlock(
+	unsigned long nr, volatile unsigned long *addr)
+{
+	__op_bit_ord(and, __NOT, nr, addr, .rl);
+}
+
+/**
+ * __clear_bit_unlock - Clear a bit in memory, for unlock
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This operation is like clear_bit_unlock, however it is not atomic.
+ * It does provide release barrier semantics so it can be used to unlock
+ * a bit lock, however it would only be used if no other CPU can modify
+ * any bits in the memory until the lock is released (a good example is
+ * if the bit lock itself protects access to the other bits in the word).
+ *
+ * On RISC-V systems there seems to be no benefit to taking advantage of the
+ * non-atomic property here: it's a lot more instructions and we still have to
+ * provide release semantics anyway.
+ */
+static inline void __clear_bit_unlock(
+	unsigned long nr, volatile unsigned long *addr)
+{
+	clear_bit_unlock(nr, addr);
+}
+
+#undef __test_and_op_bit
+#undef __op_bit
+#undef __NOP
+#undef __NOT
+#undef __AMO
+
+#include <asm-generic/bitops/non-atomic.h>
+#include <asm-generic/bitops/le.h>
+#include <asm-generic/bitops/ext2-atomic.h>
+
+#endif /* _ASM_RISCV_BITOPS_H */

arch/riscv/include/asm/bug.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_BUG_H
+#define _ASM_RISCV_BUG_H
+
+#include <linux/compiler.h>
+#include <linux/const.h>
+#include <linux/types.h>
+
+#include <asm/asm.h>
+
+#ifdef CONFIG_GENERIC_BUG
+#define __BUG_INSN	_AC(0x00100073, UL) /* ebreak */
+
+#ifndef __ASSEMBLY__
+typedef u32 bug_insn_t;
+
+#ifdef CONFIG_GENERIC_BUG_RELATIVE_POINTERS
+#define __BUG_ENTRY_ADDR	INT " 1b - 2b"
+#define __BUG_ENTRY_FILE	INT " %0 - 2b"
+#else
+#define __BUG_ENTRY_ADDR	RISCV_PTR " 1b"
+#define __BUG_ENTRY_FILE	RISCV_PTR " %0"
+#endif
+
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+#define __BUG_ENTRY			\
+	__BUG_ENTRY_ADDR "\n\t"		\
+	__BUG_ENTRY_FILE "\n\t"		\
+	SHORT " %1"
+#else
+#define __BUG_ENTRY			\
+	__BUG_ENTRY_ADDR
+#endif
+
+#define BUG()							\
+do {								\
+	__asm__ __volatile__ (					\
+		"1:\n\t"					\
+			"ebreak\n"				\
+			".pushsection __bug_table,\"a\"\n\t"	\
+		"2:\n\t"					\
+			__BUG_ENTRY "\n\t"			\
+			".org 2b + %2\n\t"			\
+			".popsection"				\
+		:						\
+		: "i" (__FILE__), "i" (__LINE__),		\
+		  "i" (sizeof(struct bug_entry)));		\
+	unreachable();						\
+} while (0)
+#endif /* !__ASSEMBLY__ */
+#else /* CONFIG_GENERIC_BUG */
+#ifndef __ASSEMBLY__
+#define BUG()							\
+do {								\
+	__asm__ __volatile__ ("ebreak\n");			\
+	unreachable();						\
+} while (0)
+#endif /* !__ASSEMBLY__ */
+#endif /* CONFIG_GENERIC_BUG */
+
+#define HAVE_ARCH_BUG
+
+#include <asm-generic/bug.h>
+
+#ifndef __ASSEMBLY__
+
+struct pt_regs;
+struct task_struct;
+
+extern void die(struct pt_regs *regs, const char *str);
+extern void do_trap(struct pt_regs *regs, int signo, int code,
+	unsigned long addr, struct task_struct *tsk);
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_BUG_H */

arch/riscv/include/asm/cache.h

+/*
+ * Copyright (C) 2017 Chen Liqin <liqin.chen@sunplusct.com>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_CACHE_H
+#define _ASM_RISCV_CACHE_H
+
+#define L1_CACHE_SHIFT		6
+
+#define L1_CACHE_BYTES		(1 << L1_CACHE_SHIFT)
+
+#endif /* _ASM_RISCV_CACHE_H */

arch/riscv/include/asm/cacheflush.h

+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_CACHEFLUSH_H
+#define _ASM_RISCV_CACHEFLUSH_H
+
+#include <asm-generic/cacheflush.h>
+
+#undef flush_icache_range
+#undef flush_icache_user_range
+
+static inline void local_flush_icache_all(void)
+{
+	asm volatile ("fence.i" ::: "memory");
+}
+
+#ifndef CONFIG_SMP
+
+#define flush_icache_range(start, end) local_flush_icache_all()
+#define flush_icache_user_range(vma, pg, addr, len) local_flush_icache_all()
+
+#else /* CONFIG_SMP */
+
+#define flush_icache_range(start, end) sbi_remote_fence_i(0)
+#define flush_icache_user_range(vma, pg, addr, len) sbi_remote_fence_i(0)
+
+#endif /* CONFIG_SMP */
+
+#endif /* _ASM_RISCV_CACHEFLUSH_H */

arch/riscv/include/asm/cmpxchg.h

+/*
+ * Copyright (C) 2014 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_CMPXCHG_H
+#define _ASM_RISCV_CMPXCHG_H
+
+#include <linux/bug.h>
+
+#include <asm/barrier.h>
+
+#define __xchg(new, ptr, size, asm_or)				\
+({								\
+	__typeof__(ptr) __ptr = (ptr);				\
+	__typeof__(new) __new = (new);				\
+	__typeof__(*(ptr)) __ret;				\
+	switch (size) {						\
+	case 4:							\
+		__asm__ __volatile__ (				\
+			"amoswap.w" #asm_or " %0, %2, %1"	\
+			: "=r" (__ret), "+A" (*__ptr)		\
+			: "r" (__new)				\
+			: "memory");				\
+		break;						\
+	case 8:							\
+		__asm__ __volatile__ (				\
+			"amoswap.d" #asm_or " %0, %2, %1"	\
+			: "=r" (__ret), "+A" (*__ptr)		\
+			: "r" (__new)				\
+			: "memory");				\
+		break;						\
+	default:						\
+		BUILD_BUG();					\
+	}							\
+	__ret;							\
+})
+
+#define xchg(ptr, x)    (__xchg((x), (ptr), sizeof(*(ptr)), .aqrl))
+
+#define xchg32(ptr, x)				\
+({						\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 4);	\
+	xchg((ptr), (x));			\
+})
+
+#define xchg64(ptr, x)				\
+({						\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 8);	\
+	xchg((ptr), (x));			\
+})
+
+/*
+ * Atomic compare and exchange.  Compare OLD with MEM, if identical,
+ * store NEW in MEM.  Return the initial value in MEM.  Success is
+ * indicated by comparing RETURN with OLD.
+ */
+#define __cmpxchg(ptr, old, new, size, lrb, scb)			\
+({									\
+	__typeof__(ptr) __ptr = (ptr);					\
+	__typeof__(*(ptr)) __old = (old);				\
+	__typeof__(*(ptr)) __new = (new);				\
+	__typeof__(*(ptr)) __ret;					\
+	register unsigned int __rc;					\
+	switch (size) {							\
+	case 4:								\
+		__asm__ __volatile__ (					\
+		"0:"							\
+			"lr.w" #scb " %0, %2\n"				\
+			"bne         %0, %z3, 1f\n"			\
+			"sc.w" #lrb " %1, %z4, %2\n"			\
+			"bnez        %1, 0b\n"				\
+		"1:"							\
+			: "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr)	\
+			: "rJ" (__old), "rJ" (__new)			\
+			: "memory");					\
+		break;							\
+	case 8:								\
+		__asm__ __volatile__ (					\
+		"0:"							\
+			"lr.d" #scb " %0, %2\n"				\
+			"bne         %0, %z3, 1f\n"			\
+			"sc.d" #lrb " %1, %z4, %2\n"			\
+			"bnez        %1, 0b\n"				\
+		"1:"							\
+			: "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr)	\
+			: "rJ" (__old), "rJ" (__new)			\
+			: "memory");					\
+		break;							\
+	default:							\
+		BUILD_BUG();						\
+	}								\
+	__ret;								\
+})
+
+#define cmpxchg(ptr, o, n) \
+	(__cmpxchg((ptr), (o), (n), sizeof(*(ptr)), .aqrl, .aqrl))
+
+#define cmpxchg_local(ptr, o, n) \
+	(__cmpxchg((ptr), (o), (n), sizeof(*(ptr)), , ))
+
+#define cmpxchg32(ptr, o, n)			\
+({						\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 4);	\
+	cmpxchg((ptr), (o), (n));		\
+})
+
+#define cmpxchg32_local(ptr, o, n)		\
+({						\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 4);	\
+	cmpxchg_local((ptr), (o), (n));		\
+})
+
+#define cmpxchg64(ptr, o, n)			\
+({						\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 8);	\
+	cmpxchg((ptr), (o), (n));		\
+})
+
+#define cmpxchg64_local(ptr, o, n)		\
+({						\
+	BUILD_BUG_ON(sizeof(*(ptr)) != 8);	\
+	cmpxchg_local((ptr), (o), (n));		\
+})
+
+#endif /* _ASM_RISCV_CMPXCHG_H */

arch/riscv/include/asm/compat.h

+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_COMPAT_H
+#define __ASM_COMPAT_H
+#ifdef CONFIG_COMPAT
+
+#if defined(CONFIG_64BIT)
+#define COMPAT_UTS_MACHINE "riscv64\0\0"
+#elif defined(CONFIG_32BIT)
+#define COMPAT_UTS_MACHINE "riscv32\0\0"
+#else
+#error "Unknown RISC-V base ISA"
+#endif
+
+#endif /*CONFIG_COMPAT*/
+#endif /*__ASM_COMPAT_H*/

arch/riscv/include/asm/csr.h

+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_CSR_H
+#define _ASM_RISCV_CSR_H
+
+#include <linux/const.h>
+
+/* Status register flags */
+#define SR_IE   _AC(0x00000002, UL) /* Interrupt Enable */
+#define SR_PIE  _AC(0x00000020, UL) /* Previous IE */
+#define SR_PS   _AC(0x00000100, UL) /* Previously Supervisor */
+#define SR_SUM  _AC(0x00040000, UL) /* Supervisor may access User Memory */
+
+#define SR_FS           _AC(0x00006000, UL) /* Floating-point Status */
+#define SR_FS_OFF       _AC(0x00000000, UL)
+#define SR_FS_INITIAL   _AC(0x00002000, UL)
+#define SR_FS_CLEAN     _AC(0x00004000, UL)
+#define SR_FS_DIRTY     _AC(0x00006000, UL)
+
+#define SR_XS           _AC(0x00018000, UL) /* Extension Status */
+#define SR_XS_OFF       _AC(0x00000000, UL)
+#define SR_XS_INITIAL   _AC(0x00008000, UL)
+#define SR_XS_CLEAN     _AC(0x00010000, UL)
+#define SR_XS_DIRTY     _AC(0x00018000, UL)
+
+#ifndef CONFIG_64BIT
+#define SR_SD   _AC(0x80000000, UL) /* FS/XS dirty */
+#else
+#define SR_SD   _AC(0x8000000000000000, UL) /* FS/XS dirty */
+#endif
+
+/* SPTBR flags */
+#if __riscv_xlen == 32
+#define SPTBR_PPN     _AC(0x003FFFFF, UL)
+#define SPTBR_MODE_32 _AC(0x80000000, UL)
+#define SPTBR_MODE    SPTBR_MODE_32
+#else
+#define SPTBR_PPN     _AC(0x00000FFFFFFFFFFF, UL)
+#define SPTBR_MODE_39 _AC(0x8000000000000000, UL)
+#define SPTBR_MODE    SPTBR_MODE_39
+#endif
+
+/* Interrupt Enable and Interrupt Pending flags */
+#define SIE_SSIE _AC(0x00000002, UL) /* Software Interrupt Enable */
+#define SIE_STIE _AC(0x00000020, UL) /* Timer Interrupt Enable */
+
+#define EXC_INST_MISALIGNED     0
+#define EXC_INST_ACCESS         1
+#define EXC_BREAKPOINT          3
+#define EXC_LOAD_ACCESS         5
+#define EXC_STORE_ACCESS        7
+#define EXC_SYSCALL             8
+#define EXC_INST_PAGE_FAULT     12
+#define EXC_LOAD_PAGE_FAULT     13
+#define EXC_STORE_PAGE_FAULT    15
+
+#ifndef __ASSEMBLY__
+
+#define csr_swap(csr, val)					\
+({								\
+	unsigned long __v = (unsigned long)(val);		\
+	__asm__ __volatile__ ("csrrw %0, " #csr ", %1"		\
+			      : "=r" (__v) : "rK" (__v)		\
+			      : "memory");			\
+	__v;							\
+})
+
+#define csr_read(csr)						\
+({								\
+	register unsigned long __v;				\
+	__asm__ __volatile__ ("csrr %0, " #csr			\
+			      : "=r" (__v) :			\
+			      : "memory");			\
+	__v;							\
+})
+
+#define csr_write(csr, val)					\
+({								\
+	unsigned long __v = (unsigned long)(val);		\
+	__asm__ __volatile__ ("csrw " #csr ", %0"		\
+			      : : "rK" (__v)			\
+			      : "memory");			\
+})
+
+#define csr_read_set(csr, val)					\
+({								\
+	unsigned long __v = (unsigned long)(val);		\
+	__asm__ __volatile__ ("csrrs %0, " #csr ", %1"		\
+			      : "=r" (__v) : "rK" (__v)		\
+			      : "memory");			\
+	__v;							\
+})
+
+#define csr_set(csr, val)					\
+({								\
+	unsigned long __v = (unsigned long)(val);		\
+	__asm__ __volatile__ ("csrs " #csr ", %0"		\
+			      : : "rK" (__v)			\
+			      : "memory");			\
+})
+
+#define csr_read_clear(csr, val)				\
+({								\
+	unsigned long __v = (unsigned long)(val);		\
+	__asm__ __volatile__ ("csrrc %0, " #csr ", %1"		\
+			      : "=r" (__v) : "rK" (__v)		\
+			      : "memory");			\
+	__v;							\
+})
+
+#define csr_clear(csr, val)					\
+({								\
+	unsigned long __v = (unsigned long)(val);		\
+	__asm__ __volatile__ ("csrc " #csr ", %0"		\
+			      : : "rK" (__v)			\
+			      : "memory");			\
+})
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_CSR_H */

arch/riscv/include/asm/current.h

+/*
+ * Based on arm/arm64/include/asm/current.h
+ *
+ * Copyright (C) 2016 ARM
+ * Copyright (C) 2017 SiFive
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+
+#ifndef __ASM_CURRENT_H
+#define __ASM_CURRENT_H
+
+#include <linux/bug.h>
+#include <linux/compiler.h>
+
+#ifndef __ASSEMBLY__
+
+struct task_struct;
+
+/*
+ * This only works because "struct thread_info" is at offset 0 from "struct
+ * task_struct".  This constraint seems to be necessary on other architectures
+ * as well, but __switch_to enforces it.  We can't check TASK_TI here because
+ * <asm/asm-offsets.h> includes this, and I can't get the definition of "struct
+ * task_struct" here due to some header ordering problems.
+ */
+static __always_inline struct task_struct *get_current(void)
+{
+	register struct task_struct *tp __asm__("tp");
+	return tp;
+}
+
+#define current get_current()
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_CURRENT_H */

arch/riscv/include/asm/delay.h

+/*
+ * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
+ * Copyright (C) 2016 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_DELAY_H
+#define _ASM_RISCV_DELAY_H
+
+extern unsigned long riscv_timebase;
+
+#define udelay udelay
+extern void udelay(unsigned long usecs);
+
+#define ndelay ndelay
+extern void ndelay(unsigned long nsecs);
+
+extern void __delay(unsigned long cycles);
+
+#endif /* _ASM_RISCV_DELAY_H */

arch/riscv/include/asm/dma-mapping.h

+/*
+ * Copyright (C) 2003-2004 Hewlett-Packard Co
+ *	David Mosberger-Tang <davidm@hpl.hp.com>
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2016 SiFive, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_RISCV_DMA_MAPPING_H
+#define __ASM_RISCV_DMA_MAPPING_H
+
+/* Use ops->dma_mapping_error (if it exists) or assume success */
+// #undef DMA_ERROR_CODE
+
+static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+{
+	return &dma_noop_ops;
+}
+
+static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
+{
+	if (!dev->dma_mask)
+		return false;
+
+	return addr + size - 1 <= *dev->dma_mask;
+}
+
+#endif	/* __ASM_RISCV_DMA_MAPPING_H */

arch/riscv/include/asm/elf.h

+/*
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef _ASM_RISCV_ELF_H
+#define _ASM_RISCV_ELF_H
+
+#include <uapi/asm/elf.h>
+#include <asm/auxvec.h>
+#include <asm/byteorder.h>
+
+/* TODO: Move definition into include/uapi/linux/elf-em.h */
+#define EM_RISCV	0xF3
+
+/*
+ * These are used to set parameters in the core dumps.
+ */
+#define ELF_ARCH	EM_RISCV
+
+#ifdef CONFIG_64BIT
+#define ELF_CLASS	ELFCLASS64
+#else
+#define ELF_CLASS	ELFCLASS32
+#endif
+
+#if defined(__LITTLE_ENDIAN)
+#define ELF_DATA	ELFDATA2LSB
+#elif defined(__BIG_ENDIAN)
+#define ELF_DATA	ELFDATA2MSB
+#else
+#error "Unknown endianness"
+#endif
+
+/*
+ * This is used to ensure we don't load something for the wrong architecture.
+ */
+#define elf_check_arch(x) ((x)->e_machine == EM_RISCV)
+
+#define CORE_DUMP_USE_REGSET
+#define ELF_EXEC_PAGESIZE	(PAGE_SIZE)
+
+/*
+ * This is the location that an ET_DYN program is loaded if exec'ed.  Typical
+ * use of this is to invoke "./ld.so someprog" to test out a new version of
+ * the loader.  We need to make sure that it is out of the way of the program
+ * that it will "exec", and that there is sufficient room for the brk.
+ */
+#define ELF_ET_DYN_BASE		((TASK_SIZE / 3) * 2)
+
+/*
+ * This yields a mask that user programs can use to figure out what
+ * instruction set this CPU supports.  This could be done in user space,
+ * but it's not easy, and we've already done it here.
+ */
+#define ELF_HWCAP	(elf_hwcap)
+extern unsigned long elf_hwcap;
+
+/*
+ * This yields a string that ld.so will use to load implementation
+ * specific libraries for optimization.  This is more specific in
+ * intent than poking at uname or /proc/cpuinfo.
+ */
+#define ELF_PLATFORM	(NULL)
+
+#define ARCH_DLINFO						\
+do {								\
+	NEW_AUX_ENT(AT_SYSINFO_EHDR,				\
+		(elf_addr_t)current->mm->context.vdso);		\
+} while (0)
+
+
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES
+struct linux_binprm;
+extern int arch_setup_additional_pages(struct linux_binprm *bprm,
+	int uses_interp);
+
+#endif /* _ASM_RISCV_ELF_H */

arch/riscv/include/asm/hwcap.h

+/*
+ * Copied from arch/arm64/include/asm/hwcap.h
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_HWCAP_H
+#define __ASM_HWCAP_H
+
+#include <uapi/asm/hwcap.h>
+
+#ifndef __ASSEMBLY__
+/*
+ * This yields a mask that user programs can use to figure out what
+ * instruction set this cpu supports.
+ */
+#define ELF_HWCAP		(elf_hwcap)
+
+enum {
+	CAP_HWCAP = 1,
+};
+
+extern unsigned long elf_hwcap;
+#endif
+#endif

arch/riscv/include/asm/irq.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_IRQ_H
+#define _ASM_RISCV_IRQ_H
+
+#define NR_IRQS         0
+
+#define INTERRUPT_CAUSE_SOFTWARE    1
+#define INTERRUPT_CAUSE_TIMER       5
+#define INTERRUPT_CAUSE_EXTERNAL    9
+
+void riscv_timer_interrupt(void);
+
+#include <asm-generic/irq.h>
+
+#endif /* _ASM_RISCV_IRQ_H */

arch/riscv/include/asm/irqflags.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+
+#ifndef _ASM_RISCV_IRQFLAGS_H
+#define _ASM_RISCV_IRQFLAGS_H
+
+#include <asm/processor.h>
+#include <asm/csr.h>
+
+/* read interrupt enabled status */
+static inline unsigned long arch_local_save_flags(void)
+{
+	return csr_read(sstatus);
+}
+
+/* unconditionally enable interrupts */
+static inline void arch_local_irq_enable(void)
+{
+	csr_set(sstatus, SR_IE);
+}
+
+/* unconditionally disable interrupts */
+static inline void arch_local_irq_disable(void)
+{
+	csr_clear(sstatus, SR_IE);
+}
+
+/* get status and disable interrupts */
+static inline unsigned long arch_local_irq_save(void)
+{
+	return csr_read_clear(sstatus, SR_IE);
+}
+
+/* test flags */
+static inline int arch_irqs_disabled_flags(unsigned long flags)
+{
+	return !(flags & SR_IE);
+}
+
+/* test hardware interrupt enable bit */
+static inline int arch_irqs_disabled(void)
+{
+	return arch_irqs_disabled_flags(arch_local_save_flags());
+}
+
+/* set interrupt enabled status */
+static inline void arch_local_irq_restore(unsigned long flags)
+{
+	csr_set(sstatus, flags & SR_IE);
+}
+
+#endif /* _ASM_RISCV_IRQFLAGS_H */

arch/riscv/include/asm/kprobes.h

+/*
+ * Copied from arch/arm64/include/asm/kprobes.h
+ *
+ * Copyright (C) 2013 Linaro Limited
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#ifndef _RISCV_KPROBES_H
+#define _RISCV_KPROBES_H
+
+#include <asm-generic/kprobes.h>
+
+#endif /* _RISCV_KPROBES_H */

arch/riscv/include/asm/linkage.h

+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_LINKAGE_H
+#define _ASM_RISCV_LINKAGE_H
+
+#define __ALIGN		.balign 4
+#define __ALIGN_STR	".balign 4"
+
+#endif /* _ASM_RISCV_LINKAGE_H */

arch/riscv/include/asm/mmu.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+
+#ifndef _ASM_RISCV_MMU_H
+#define _ASM_RISCV_MMU_H
+
+#ifndef __ASSEMBLY__
+
+typedef struct {
+	void *vdso;
+} mm_context_t;
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_MMU_H */

arch/riscv/include/asm/mmu_context.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_MMU_CONTEXT_H
+#define _ASM_RISCV_MMU_CONTEXT_H
+
+#include <asm-generic/mm_hooks.h>
+
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <asm/tlbflush.h>
+
+static inline void enter_lazy_tlb(struct mm_struct *mm,
+	struct task_struct *task)
+{
+}
+
+/* Initialize context-related info for a new mm_struct */
+static inline int init_new_context(struct task_struct *task,
+	struct mm_struct *mm)
+{
+	return 0;
+}
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+}
+
+static inline pgd_t *current_pgdir(void)
+{
+	return pfn_to_virt(csr_read(sptbr) & SPTBR_PPN);
+}
+
+static inline void set_pgdir(pgd_t *pgd)
+{
+	csr_write(sptbr, virt_to_pfn(pgd) | SPTBR_MODE);
+}
+
+static inline void switch_mm(struct mm_struct *prev,
+	struct mm_struct *next, struct task_struct *task)
+{
+	if (likely(prev != next)) {
+		set_pgdir(next->pgd);
+		local_flush_tlb_all();
+	}
+}
+
+static inline void activate_mm(struct mm_struct *prev,
+			       struct mm_struct *next)
+{
+	switch_mm(prev, next, NULL);
+}
+
+static inline void deactivate_mm(struct task_struct *task,
+	struct mm_struct *mm)
+{
+}
+
+#endif /* _ASM_RISCV_MMU_CONTEXT_H */

arch/riscv/include/asm/page.h

+/*
+ * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ * Copyright (C) 2017 XiaojingZhu <zhuxiaoj@ict.ac.cn>
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PAGE_H
+#define _ASM_RISCV_PAGE_H
+
+#include <linux/pfn.h>
+#include <linux/const.h>
+
+#define PAGE_SHIFT	(12)
+#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
+#define PAGE_MASK	(~(PAGE_SIZE - 1))
+
+/*
+ * PAGE_OFFSET -- the first address of the first page of memory.
+ * When not using MMU this corresponds to the first free page in
+ * physical memory (aligned on a page boundary).
+ */
+#define PAGE_OFFSET		_AC(CONFIG_PAGE_OFFSET, UL)
+
+#define KERN_VIRT_SIZE (-PAGE_OFFSET)
+
+#ifndef __ASSEMBLY__
+
+#define PAGE_UP(addr)	(((addr)+((PAGE_SIZE)-1))&(~((PAGE_SIZE)-1)))
+#define PAGE_DOWN(addr)	((addr)&(~((PAGE_SIZE)-1)))
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr, size)	(((addr)+((size)-1))&(~((size)-1)))
+#define _ALIGN_DOWN(addr, size)	((addr)&(~((size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr, size)	_ALIGN_UP(addr, size)
+
+#define clear_page(pgaddr)			memset((pgaddr), 0, PAGE_SIZE)
+#define copy_page(to, from)			memcpy((to), (from), PAGE_SIZE)
+
+#define clear_user_page(pgaddr, vaddr, page)	memset((pgaddr), 0, PAGE_SIZE)
+#define copy_user_page(vto, vfrom, vaddr, topg) \
+			memcpy((vto), (vfrom), PAGE_SIZE)
+
+/*
+ * Use struct definitions to apply C type checking
+ */
+
+/* Page Global Directory entry */
+typedef struct {
+	unsigned long pgd;
+} pgd_t;
+
+/* Page Table entry */
+typedef struct {
+	unsigned long pte;
+} pte_t;
+
+typedef struct {
+	unsigned long pgprot;
+} pgprot_t;
+
+typedef struct page *pgtable_t;
+
+#define pte_val(x)	((x).pte)
+#define pgd_val(x)	((x).pgd)
+#define pgprot_val(x)	((x).pgprot)
+
+#define __pte(x)	((pte_t) { (x) })
+#define __pgd(x)	((pgd_t) { (x) })
+#define __pgprot(x)	((pgprot_t) { (x) })
+
+#ifdef CONFIG_64BITS
+#define PTE_FMT "%016lx"
+#else
+#define PTE_FMT "%08lx"
+#endif
+
+extern unsigned long va_pa_offset;
+extern unsigned long pfn_base;
+
+extern unsigned long max_low_pfn;
+extern unsigned long min_low_pfn;
+
+#define __pa(x)		((unsigned long)(x) - va_pa_offset)
+#define __va(x)		((void *)((unsigned long) (x) + va_pa_offset))
+
+#define phys_to_pfn(phys)	(PFN_DOWN(phys))
+#define pfn_to_phys(pfn)	(PFN_PHYS(pfn))
+
+#define virt_to_pfn(vaddr)	(phys_to_pfn(__pa(vaddr)))
+#define pfn_to_virt(pfn)	(__va(pfn_to_phys(pfn)))
+
+#define virt_to_page(vaddr)	(pfn_to_page(virt_to_pfn(vaddr)))
+#define page_to_virt(page)	(pfn_to_virt(page_to_pfn(page)))
+
+#define page_to_phys(page)	(pfn_to_phys(page_to_pfn(page)))
+#define page_to_bus(page)	(page_to_phys(page))
+#define phys_to_page(paddr)	(pfn_to_page(phys_to_pfn(paddr)))
+
+#define pfn_valid(pfn) \
+	(((pfn) >= pfn_base) && (((pfn)-pfn_base) < max_mapnr))
+
+#define ARCH_PFN_OFFSET		(pfn_base)
+
+#endif /* __ASSEMBLY__ */
+
+#define virt_addr_valid(vaddr)	(pfn_valid(virt_to_pfn(vaddr)))
+
+#define VM_DATA_DEFAULT_FLAGS	(VM_READ | VM_WRITE | \
+				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#include <asm-generic/memory_model.h>
+#include <asm-generic/getorder.h>
+
+/* vDSO support */
+/* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */
+#define __HAVE_ARCH_GATE_AREA
+
+#endif /* _ASM_RISCV_PAGE_H */

arch/riscv/include/asm/pci.h

+/*
+ * Copyright (C) 2016 SiFive
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef __ASM_RISCV_PCI_H
+#define __ASM_RISCV_PCI_H
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/io.h>
+
+#define PCIBIOS_MIN_IO		0
+#define PCIBIOS_MIN_MEM		0
+
+/* RISC-V shim does not initialize PCI bus */
+#define pcibios_assign_all_busses() 1
+
+/* We do not have an IOMMU */
+#define PCI_DMA_BUS_IS_PHYS 1
+
+extern int isa_dma_bridge_buggy;
+
+#ifdef CONFIG_PCI
+static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
+{
+	/* no legacy IRQ on risc-v */
+	return -ENODEV;
+}
+
+static inline int pci_proc_domain(struct pci_bus *bus)
+{
+	/* always show the domain in /proc */
+	return 1;
+}
+#endif  /* CONFIG_PCI */
+
+#endif  /* __ASM_PCI_H */

arch/riscv/include/asm/pgalloc.h

+/*
+ * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PGALLOC_H
+#define _ASM_RISCV_PGALLOC_H
+
+#include <linux/mm.h>
+#include <asm/tlb.h>
+
+static inline void pmd_populate_kernel(struct mm_struct *mm,
+	pmd_t *pmd, pte_t *pte)
+{
+	unsigned long pfn = virt_to_pfn(pte);
+
+	set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
+}
+
+static inline void pmd_populate(struct mm_struct *mm,
+	pmd_t *pmd, pgtable_t pte)
+{
+	unsigned long pfn = virt_to_pfn(page_address(pte));
+
+	set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
+}
+
+#ifndef __PAGETABLE_PMD_FOLDED
+static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
+{
+	unsigned long pfn = virt_to_pfn(pmd);
+
+	set_pud(pud, __pud((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
+}
+#endif /* __PAGETABLE_PMD_FOLDED */
+
+#define pmd_pgtable(pmd)	pmd_page(pmd)
+
+static inline pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+	pgd_t *pgd;
+
+	pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
+	if (likely(pgd != NULL)) {
+		memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
+		/* Copy kernel mappings */
+		memcpy(pgd + USER_PTRS_PER_PGD,
+			init_mm.pgd + USER_PTRS_PER_PGD,
+			(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+	}
+	return pgd;
+}
+
+static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+	free_page((unsigned long)pgd);
+}
+
+#ifndef __PAGETABLE_PMD_FOLDED
+
+static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
+{
+	return (pmd_t *)__get_free_page(
+		GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
+}
+
+static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
+{
+	free_page((unsigned long)pmd);
+}
+
+#define __pmd_free_tlb(tlb, pmd, addr)  pmd_free((tlb)->mm, pmd)
+
+#endif /* __PAGETABLE_PMD_FOLDED */
+
+static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
+	unsigned long address)
+{
+	return (pte_t *)__get_free_page(
+		GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
+}
+
+static inline struct page *pte_alloc_one(struct mm_struct *mm,
+	unsigned long address)
+{
+	struct page *pte;
+
+	pte = alloc_page(GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_ZERO);
+	if (likely(pte != NULL))
+		pgtable_page_ctor(pte);
+	return pte;
+}
+
+static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
+{
+	free_page((unsigned long)pte);
+}
+
+static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
+{
+	pgtable_page_dtor(pte);
+	__free_page(pte);
+}
+
+#define __pte_free_tlb(tlb, pte, buf)   \
+do {                                    \
+	pgtable_page_dtor(pte);         \
+	tlb_remove_page((tlb), pte);    \
+} while (0)
+
+static inline void check_pgt_cache(void)
+{
+}
+
+#endif /* _ASM_RISCV_PGALLOC_H */

arch/riscv/include/asm/pgtable-32.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PGTABLE_32_H
+#define _ASM_RISCV_PGTABLE_32_H
+
+#include <asm-generic/pgtable-nopmd.h>
+#include <linux/const.h>
+
+/* Size of region mapped by a page global directory */
+#define PGDIR_SHIFT     22
+#define PGDIR_SIZE      (_AC(1, UL) << PGDIR_SHIFT)
+#define PGDIR_MASK      (~(PGDIR_SIZE - 1))
+
+#endif /* _ASM_RISCV_PGTABLE_32_H */

arch/riscv/include/asm/pgtable-64.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PGTABLE_64_H
+#define _ASM_RISCV_PGTABLE_64_H
+
+#include <linux/const.h>
+
+#define PGDIR_SHIFT     30
+/* Size of region mapped by a page global directory */
+#define PGDIR_SIZE      (_AC(1, UL) << PGDIR_SHIFT)
+#define PGDIR_MASK      (~(PGDIR_SIZE - 1))
+
+#define PMD_SHIFT       21
+/* Size of region mapped by a page middle directory */
+#define PMD_SIZE        (_AC(1, UL) << PMD_SHIFT)
+#define PMD_MASK        (~(PMD_SIZE - 1))
+
+/* Page Middle Directory entry */
+typedef struct {
+	unsigned long pmd;
+} pmd_t;
+
+#define pmd_val(x)      ((x).pmd)
+#define __pmd(x)        ((pmd_t) { (x) })
+
+#define PTRS_PER_PMD    (PAGE_SIZE / sizeof(pmd_t))
+
+static inline int pud_present(pud_t pud)
+{
+	return (pud_val(pud) & _PAGE_PRESENT);
+}
+
+static inline int pud_none(pud_t pud)
+{
+	return (pud_val(pud) == 0);
+}
+
+static inline int pud_bad(pud_t pud)
+{
+	return !pud_present(pud);
+}
+
+static inline void set_pud(pud_t *pudp, pud_t pud)
+{
+	*pudp = pud;
+}
+
+static inline void pud_clear(pud_t *pudp)
+{
+	set_pud(pudp, __pud(0));
+}
+
+static inline unsigned long pud_page_vaddr(pud_t pud)
+{
+	return (unsigned long)pfn_to_virt(pud_val(pud) >> _PAGE_PFN_SHIFT);
+}
+
+#define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
+
+static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
+{
+	return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr);
+}
+
+static inline pmd_t pfn_pmd(unsigned long pfn, pgprot_t prot)
+{
+	return __pmd((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot));
+}
+
+#define pmd_ERROR(e) \
+	pr_err("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
+
+#endif /* _ASM_RISCV_PGTABLE_64_H */

arch/riscv/include/asm/pgtable-bits.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PGTABLE_BITS_H
+#define _ASM_RISCV_PGTABLE_BITS_H
+
+/*
+ * PTE format:
+ * | XLEN-1  10 | 9             8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
+ *       PFN      reserved for SW   D   A   G   U   X   W   R   V
+ */
+
+#define _PAGE_ACCESSED_OFFSET 6
+
+#define _PAGE_PRESENT   (1 << 0)
+#define _PAGE_READ      (1 << 1)    /* Readable */
+#define _PAGE_WRITE     (1 << 2)    /* Writable */
+#define _PAGE_EXEC      (1 << 3)    /* Executable */
+#define _PAGE_USER      (1 << 4)    /* User */
+#define _PAGE_GLOBAL    (1 << 5)    /* Global */
+#define _PAGE_ACCESSED  (1 << 6)    /* Set by hardware on any access */
+#define _PAGE_DIRTY     (1 << 7)    /* Set by hardware on any write */
+#define _PAGE_SOFT      (1 << 8)    /* Reserved for software */
+
+#define _PAGE_SPECIAL   _PAGE_SOFT
+#define _PAGE_TABLE     _PAGE_PRESENT
+
+#define _PAGE_PFN_SHIFT 10
+
+/* Set of bits to preserve across pte_modify() */
+#define _PAGE_CHG_MASK  (~(unsigned long)(_PAGE_PRESENT | _PAGE_READ |	\
+					  _PAGE_WRITE | _PAGE_EXEC |	\
+					  _PAGE_USER | _PAGE_GLOBAL))
+
+/* Advertise support for _PAGE_SPECIAL */
+#define __HAVE_ARCH_PTE_SPECIAL
+
+#endif /* _ASM_RISCV_PGTABLE_BITS_H */

arch/riscv/include/asm/processor.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PROCESSOR_H
+#define _ASM_RISCV_PROCESSOR_H
+
+#include <linux/const.h>
+
+#include <asm/ptrace.h>
+
+/*
+ * This decides where the kernel will search for a free chunk of vm
+ * space during mmap's.
+ */
+#define TASK_UNMAPPED_BASE	PAGE_ALIGN(TASK_SIZE >> 1)
+
+#define STACK_TOP		TASK_SIZE
+#define STACK_TOP_MAX		STACK_TOP
+#define STACK_ALIGN		16
+
+#ifndef __ASSEMBLY__
+
+struct task_struct;
+struct pt_regs;
+
+/*
+ * Default implementation of macro that returns current
+ * instruction pointer ("program counter").
+ */
+#define current_text_addr()	({ __label__ _l; _l: &&_l; })
+
+/* CPU-specific state of a task */
+struct thread_struct {
+	/* Callee-saved registers */
+	unsigned long ra;
+	unsigned long sp;	/* Kernel mode stack */
+	unsigned long s[12];	/* s[0]: frame pointer */
+	struct __riscv_d_ext_state fstate;
+};
+
+#define INIT_THREAD {					\
+	.sp = sizeof(init_stack) + (long)&init_stack,	\
+}
+
+#define task_pt_regs(tsk)						\
+	((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE		\
+			    - ALIGN(sizeof(struct pt_regs), STACK_ALIGN)))
+
+#define KSTK_EIP(tsk)		(task_pt_regs(tsk)->sepc)
+#define KSTK_ESP(tsk)		(task_pt_regs(tsk)->sp)
+
+
+/* Do necessary setup to start up a newly executed thread. */
+extern void start_thread(struct pt_regs *regs,
+			unsigned long pc, unsigned long sp);
+
+/* Free all resources held by a thread. */
+static inline void release_thread(struct task_struct *dead_task)
+{
+}
+
+extern unsigned long get_wchan(struct task_struct *p);
+
+
+static inline void cpu_relax(void)
+{
+#ifdef __riscv_muldiv
+	int dummy;
+	/* In lieu of a halt instruction, induce a long-latency stall. */
+	__asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy));
+#endif
+	barrier();
+}
+
+static inline void wait_for_interrupt(void)
+{
+	__asm__ __volatile__ ("wfi");
+}
+
+struct device_node;
+extern int riscv_of_processor_hart(struct device_node *node);
+
+extern void riscv_fill_hwcap(void);
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_PROCESSOR_H */

arch/riscv/include/asm/ptrace.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PTRACE_H
+#define _ASM_RISCV_PTRACE_H
+
+#include <uapi/asm/ptrace.h>
+#include <asm/csr.h>
+
+#ifndef __ASSEMBLY__
+
+struct pt_regs {
+	unsigned long sepc;
+	unsigned long ra;
+	unsigned long sp;
+	unsigned long gp;
+	unsigned long tp;
+	unsigned long t0;
+	unsigned long t1;
+	unsigned long t2;
+	unsigned long s0;
+	unsigned long s1;
+	unsigned long a0;
+	unsigned long a1;
+	unsigned long a2;
+	unsigned long a3;
+	unsigned long a4;
+	unsigned long a5;
+	unsigned long a6;
+	unsigned long a7;
+	unsigned long s2;
+	unsigned long s3;
+	unsigned long s4;
+	unsigned long s5;
+	unsigned long s6;
+	unsigned long s7;
+	unsigned long s8;
+	unsigned long s9;
+	unsigned long s10;
+	unsigned long s11;
+	unsigned long t3;
+	unsigned long t4;
+	unsigned long t5;
+	unsigned long t6;
+	/* Supervisor CSRs */
+	unsigned long sstatus;
+	unsigned long sbadaddr;
+	unsigned long scause;
+        /* a0 value before the syscall */
+        unsigned long orig_a0;
+};
+
+#ifdef CONFIG_64BIT
+#define REG_FMT "%016lx"
+#else
+#define REG_FMT "%08lx"
+#endif
+
+#define user_mode(regs) (((regs)->sstatus & SR_PS) == 0)
+
+
+/* Helpers for working with the instruction pointer */
+#define GET_IP(regs) ((regs)->sepc)
+#define SET_IP(regs, val) (GET_IP(regs) = (val))
+
+static inline unsigned long instruction_pointer(struct pt_regs *regs)
+{
+	return GET_IP(regs);
+}
+static inline void instruction_pointer_set(struct pt_regs *regs,
+					   unsigned long val)
+{
+	SET_IP(regs, val);
+}
+
+#define profile_pc(regs) instruction_pointer(regs)
+
+/* Helpers for working with the user stack pointer */
+#define GET_USP(regs) ((regs)->sp)
+#define SET_USP(regs, val) (GET_USP(regs) = (val))
+
+static inline unsigned long user_stack_pointer(struct pt_regs *regs)
+{
+	return GET_USP(regs);
+}
+static inline void user_stack_pointer_set(struct pt_regs *regs,
+					  unsigned long val)
+{
+	SET_USP(regs, val);
+}
+
+/* Helpers for working with the frame pointer */
+#define GET_FP(regs) ((regs)->s0)
+#define SET_FP(regs, val) (GET_FP(regs) = (val))
+
+static inline unsigned long frame_pointer(struct pt_regs *regs)
+{
+	return GET_FP(regs);
+}
+static inline void frame_pointer_set(struct pt_regs *regs,
+				     unsigned long val)
+{
+	SET_FP(regs, val);
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_PTRACE_H */

arch/riscv/include/asm/sbi.h

+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_SBI_H
+#define _ASM_RISCV_SBI_H
+
+#include <linux/types.h>
+
+#define SBI_SET_TIMER 0
+#define SBI_CONSOLE_PUTCHAR 1
+#define SBI_CONSOLE_GETCHAR 2
+#define SBI_CLEAR_IPI 3
+#define SBI_SEND_IPI 4
+#define SBI_REMOTE_FENCE_I 5
+#define SBI_REMOTE_SFENCE_VMA 6
+#define SBI_REMOTE_SFENCE_VMA_ASID 7
+#define SBI_SHUTDOWN 8
+
+#define SBI_CALL(which, arg0, arg1, arg2) ({			\
+	register uintptr_t a0 asm ("a0") = (uintptr_t)(arg0);	\
+	register uintptr_t a1 asm ("a1") = (uintptr_t)(arg1);	\
+	register uintptr_t a2 asm ("a2") = (uintptr_t)(arg2);	\
+	register uintptr_t a7 asm ("a7") = (uintptr_t)(which);	\
+	asm volatile ("ecall"					\
+		      : "+r" (a0)				\
+		      : "r" (a1), "r" (a2), "r" (a7)		\
+		      : "memory");				\
+	a0;							\
+})
+
+/* Lazy implementations until SBI is finalized */
+#define SBI_CALL_0(which) SBI_CALL(which, 0, 0, 0)
+#define SBI_CALL_1(which, arg0) SBI_CALL(which, arg0, 0, 0)
+#define SBI_CALL_2(which, arg0, arg1) SBI_CALL(which, arg0, arg1, 0)
+
+static inline void sbi_console_putchar(int ch)
+{
+	SBI_CALL_1(SBI_CONSOLE_PUTCHAR, ch);
+}
+
+static inline int sbi_console_getchar(void)
+{
+	return SBI_CALL_0(SBI_CONSOLE_GETCHAR);
+}
+
+static inline void sbi_set_timer(uint64_t stime_value)
+{
+#if __riscv_xlen == 32
+	SBI_CALL_2(SBI_SET_TIMER, stime_value, stime_value >> 32);
+#else
+	SBI_CALL_1(SBI_SET_TIMER, stime_value);
+#endif
+}
+
+static inline void sbi_shutdown(void)
+{
+	SBI_CALL_0(SBI_SHUTDOWN);
+}
+
+static inline void sbi_clear_ipi(void)
+{
+	SBI_CALL_0(SBI_CLEAR_IPI);
+}
+
+static inline void sbi_send_ipi(const unsigned long *hart_mask)
+{
+	SBI_CALL_1(SBI_SEND_IPI, hart_mask);
+}
+
+static inline void sbi_remote_fence_i(const unsigned long *hart_mask)
+{
+	SBI_CALL_1(SBI_REMOTE_FENCE_I, hart_mask);
+}
+
+static inline void sbi_remote_sfence_vma(const unsigned long *hart_mask,
+					 unsigned long start,
+					 unsigned long size)
+{
+	SBI_CALL_1(SBI_REMOTE_SFENCE_VMA, hart_mask);
+}
+
+static inline void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
+					      unsigned long start,
+					      unsigned long size,
+					      unsigned long asid)
+{
+	SBI_CALL_1(SBI_REMOTE_SFENCE_VMA_ASID, hart_mask);
+}
+
+#endif

arch/riscv/include/asm/smp.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_SMP_H
+#define _ASM_RISCV_SMP_H
+
+/* This both needs asm-offsets.h and is used when generating it. */
+#ifndef GENERATING_ASM_OFFSETS
+#include <asm/asm-offsets.h>
+#endif
+
+#include <linux/cpumask.h>
+#include <linux/irqreturn.h>
+
+#ifdef CONFIG_SMP
+
+/* SMP initialization hook for setup_arch */
+void __init init_clockevent(void);
+
+/* SMP initialization hook for setup_arch */
+void __init setup_smp(void);
+
+/* Hook for the generic smp_call_function_many() routine. */
+void arch_send_call_function_ipi_mask(struct cpumask *mask);
+
+/* Hook for the generic smp_call_function_single() routine. */
+void arch_send_call_function_single_ipi(int cpu);
+
+/*
+ * This is particularly ugly: it appears we can't actually get the definition
+ * of task_struct here, but we need access to the CPU this task is running on.
+ * Instead of using C we're using asm-offsets.h to get the current processor
+ * ID.
+ */
+#define raw_smp_processor_id() (*((int*)((char*)get_current() + TASK_TI_CPU)))
+
+/* Interprocessor interrupt handler */
+irqreturn_t handle_ipi(void);
+
+#endif /* CONFIG_SMP */
+
+#endif /* _ASM_RISCV_SMP_H */

arch/riscv/include/asm/spinlock.h

+/*
+ * Copyright (C) 2015 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_SPINLOCK_H
+#define _ASM_RISCV_SPINLOCK_H
+
+#include <linux/kernel.h>
+#include <asm/current.h>
+
+/*
+ * Simple spin lock operations.  These provide no fairness guarantees.
+ */
+
+/* FIXME: Replace this with a ticket lock, like MIPS. */
+
+#define arch_spin_is_locked(x)	((x)->lock != 0)
+
+static inline void arch_spin_unlock(arch_spinlock_t *lock)
+{
+	__asm__ __volatile__ (
+		"amoswap.w.rl x0, x0, %0"
+		: "=A" (lock->lock)
+		:: "memory");
+}
+
+static inline int arch_spin_trylock(arch_spinlock_t *lock)
+{
+	int tmp = 1, busy;
+
+	__asm__ __volatile__ (
+		"amoswap.w.aq %0, %2, %1"
+		: "=r" (busy), "+A" (lock->lock)
+		: "r" (tmp)
+		: "memory");
+
+	return !busy;
+}
+
+static inline void arch_spin_lock(arch_spinlock_t *lock)
+{
+	while (1) {
+		if (arch_spin_is_locked(lock))
+			continue;
+
+		if (arch_spin_trylock(lock))
+			break;
+	}
+}
+
+static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
+{
+	smp_rmb();
+	do {
+		cpu_relax();
+	} while (arch_spin_is_locked(lock));
+	smp_acquire__after_ctrl_dep();
+}
+
+/***********************************************************/
+
+static inline void arch_read_lock(arch_rwlock_t *lock)
+{
+	int tmp;
+
+	__asm__ __volatile__(
+		"1:	lr.w	%1, %0\n"
+		"	bltz	%1, 1b\n"
+		"	addi	%1, %1, 1\n"
+		"	sc.w.aq	%1, %1, %0\n"
+		"	bnez	%1, 1b\n"
+		: "+A" (lock->lock), "=&r" (tmp)
+		:: "memory");
+}
+
+static inline void arch_write_lock(arch_rwlock_t *lock)
+{
+	int tmp;
+
+	__asm__ __volatile__(
+		"1:	lr.w	%1, %0\n"
+		"	bnez	%1, 1b\n"
+		"	li	%1, -1\n"
+		"	sc.w.aq	%1, %1, %0\n"
+		"	bnez	%1, 1b\n"
+		: "+A" (lock->lock), "=&r" (tmp)
+		:: "memory");
+}
+
+static inline int arch_read_trylock(arch_rwlock_t *lock)
+{
+	int busy;
+
+	__asm__ __volatile__(
+		"1:	lr.w	%1, %0\n"
+		"	bltz	%1, 1f\n"
+		"	addi	%1, %1, 1\n"
+		"	sc.w.aq	%1, %1, %0\n"
+		"	bnez	%1, 1b\n"
+		"1:\n"
+		: "+A" (lock->lock), "=&r" (busy)
+		:: "memory");
+
+	return !busy;
+}
+
+static inline int arch_write_trylock(arch_rwlock_t *lock)
+{
+	int busy;
+
+	__asm__ __volatile__(
+		"1:	lr.w	%1, %0\n"
+		"	bnez	%1, 1f\n"
+		"	li	%1, -1\n"
+		"	sc.w.aq	%1, %1, %0\n"
+		"	bnez	%1, 1b\n"
+		"1:\n"
+		: "+A" (lock->lock), "=&r" (busy)
+		:: "memory");
+
+	return !busy;
+}
+
+static inline void arch_read_unlock(arch_rwlock_t *lock)
+{
+	__asm__ __volatile__(
+		"amoadd.w.rl x0, %1, %0"
+		: "+A" (lock->lock)
+		: "r" (-1)
+		: "memory");
+}
+
+static inline void arch_write_unlock(arch_rwlock_t *lock)
+{
+	__asm__ __volatile__ (
+		"amoswap.w.rl x0, x0, %0"
+		: "=A" (lock->lock)
+		:: "memory");
+}
+
+#endif /* _ASM_RISCV_SPINLOCK_H */

arch/riscv/include/asm/spinlock_types.h

+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_SPINLOCK_TYPES_H
+#define _ASM_RISCV_SPINLOCK_TYPES_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+# error "please don't include this file directly"
+#endif
+
+typedef struct {
+	volatile unsigned int lock;
+} arch_spinlock_t;
+
+#define __ARCH_SPIN_LOCK_UNLOCKED	{ 0 }
+
+typedef struct {
+	volatile unsigned int lock;
+} arch_rwlock_t;
+
+#define __ARCH_RW_LOCK_UNLOCKED		{ 0 }
+
+#endif

arch/riscv/include/asm/string.h

+/*
+ * Copyright (C) 2013 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_STRING_H
+#define _ASM_RISCV_STRING_H
+
+#include <linux/types.h>
+#include <linux/linkage.h>
+
+#define __HAVE_ARCH_MEMSET
+extern asmlinkage void *memset(void *, int, size_t);
+
+#define __HAVE_ARCH_MEMCPY
+extern asmlinkage void *memcpy(void *, const void *, size_t);
+
+#endif /* _ASM_RISCV_STRING_H */

arch/riscv/include/asm/switch_to.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_SWITCH_TO_H
+#define _ASM_RISCV_SWITCH_TO_H
+
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+#include <asm/csr.h>
+
+extern void __fstate_save(struct task_struct *save_to);
+extern void __fstate_restore(struct task_struct *restore_from);
+
+static inline void __fstate_clean(struct pt_regs *regs)
+{
+	regs->sstatus |= (regs->sstatus & ~(SR_FS)) | SR_FS_CLEAN;
+}
+
+static inline void fstate_save(struct task_struct *task,
+			       struct pt_regs *regs)
+{
+	if ((regs->sstatus & SR_FS) == SR_FS_DIRTY) {
+		__fstate_save(task);
+		__fstate_clean(regs);
+	}
+}
+
+static inline void fstate_restore(struct task_struct *task,
+				  struct pt_regs *regs)
+{
+	if ((regs->sstatus & SR_FS) != SR_FS_OFF) {
+		__fstate_restore(task);
+		__fstate_clean(regs);
+	}
+}
+
+static inline void __switch_to_aux(struct task_struct *prev,
+				   struct task_struct *next)
+{
+	struct pt_regs *regs;
+
+	regs = task_pt_regs(prev);
+	if (unlikely(regs->sstatus & SR_SD))
+		fstate_save(prev, regs);
+	fstate_restore(next, task_pt_regs(next));
+}
+
+extern struct task_struct *__switch_to(struct task_struct *,
+				       struct task_struct *);
+
+#define switch_to(prev, next, last)			\
+do {							\
+	struct task_struct *__prev = (prev);		\
+	struct task_struct *__next = (next);		\
+	__switch_to_aux(__prev, __next);		\
+	((last) = __switch_to(__prev, __next));		\
+} while (0)
+
+#endif /* _ASM_RISCV_SWITCH_TO_H */

arch/riscv/include/asm/syscall.h

+/*
+ * Copyright (C) 2008-2009 Red Hat, Inc.  All rights reserved.
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ * Copyright 2015 Regents of the University of California, Berkeley
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ * See asm-generic/syscall.h for descriptions of what we must do here.
+ */
+
+#ifndef _ASM_RISCV_SYSCALL_H
+#define _ASM_RISCV_SYSCALL_H
+
+#include <linux/sched.h>
+#include <linux/err.h>
+
+/* The array of function pointers for syscalls. */
+extern void *sys_call_table[];
+
+/*
+ * Only the low 32 bits of orig_r0 are meaningful, so we return int.
+ * This importantly ignores the high bits on 64-bit, so comparisons
+ * sign-extend the low 32 bits.
+ */
+static inline int syscall_get_nr(struct task_struct *task,
+				 struct pt_regs *regs)
+{
+	return regs->a7;
+}
+
+static inline void syscall_set_nr(struct task_struct *task,
+				  struct pt_regs *regs,
+				  int sysno)
+{
+	regs->a7 = sysno;
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+				    struct pt_regs *regs)
+{
+        regs->a0 = regs->orig_a0;
+}
+
+static inline long syscall_get_error(struct task_struct *task,
+				     struct pt_regs *regs)
+{
+	unsigned long error = regs->a0;
+
+	return IS_ERR_VALUE(error) ? error : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+					    struct pt_regs *regs)
+{
+	return regs->a0;
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+					    struct pt_regs *regs,
+					    int error, long val)
+{
+	regs->a0 = (long) error ?: val;
+}
+
+static inline void syscall_get_arguments(struct task_struct *task,
+					 struct pt_regs *regs,
+					 unsigned int i, unsigned int n,
+					 unsigned long *args)
+{
+	BUG_ON(i + n > 6);
+	if (i == 0) {
+		args[0] = regs->orig_a0;
+		args++;
+		i++;
+		n--;
+	}
+	memcpy(args, &regs->a1 + i * sizeof(regs->a1), n * sizeof(args[0]));
+}
+
+static inline void syscall_set_arguments(struct task_struct *task,
+					 struct pt_regs *regs,
+					 unsigned int i, unsigned int n,
+					 const unsigned long *args)
+{
+	BUG_ON(i + n > 6);
+        if (i == 0) {
+                regs->orig_a0 = args[0];
+                args++;
+                i++;
+                n--;
+        }
+	memcpy(&regs->a1 + i * sizeof(regs->a1), args, n * sizeof(regs->a0));
+}
+
+#endif	/* _ASM_RISCV_SYSCALL_H */

arch/riscv/include/asm/thread_info.h

+/*
+ * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_THREAD_INFO_H
+#define _ASM_RISCV_THREAD_INFO_H
+
+#include <asm/page.h>
+#include <linux/const.h>
+
+/* thread information allocation */
+#define THREAD_SIZE_ORDER	(1)
+#define THREAD_SIZE		(PAGE_SIZE << THREAD_SIZE_ORDER)
+
+#ifndef __ASSEMBLY__
+
+#include <asm/processor.h>
+#include <asm/csr.h>
+
+typedef unsigned long mm_segment_t;
+
+/*
+ * low level task data that entry.S needs immediate access to
+ * - this struct should fit entirely inside of one cache line
+ * - if the members of this struct changes, the assembly constants
+ *   in asm-offsets.c must be updated accordingly
+ * - thread_info is included in task_struct at an offset of 0.  This means that
+ *   tp points to both thread_info and task_struct.
+ */
+struct thread_info {
+	unsigned long		flags;		/* low level flags */
+	int                     preempt_count;  /* 0=>preemptible, <0=>BUG */
+	mm_segment_t		addr_limit;
+	/*
+	 * These stack pointers are overwritten on every system call or
+	 * exception.  SP is also saved to the stack it can be recovered when
+	 * overwritten.
+	 */
+	long			kernel_sp;	/* Kernel stack pointer */
+	long			user_sp;	/* User stack pointer */
+	int			cpu;
+};
+
+/*
+ * macros/functions for gaining access to the thread information structure
+ *
+ * preempt_count needs to be 1 initially, until the scheduler is functional.
+ */
+#define INIT_THREAD_INFO(tsk)			\
+{						\
+	.flags		= 0,			\
+	.preempt_count	= INIT_PREEMPT_COUNT,	\
+	.addr_limit	= KERNEL_DS,		\
+}
+
+#define init_stack		(init_thread_union.stack)
+
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * thread information flags
+ * - these are process state flags that various assembly files may need to
+ *   access
+ * - pending work-to-be-done flags are in lowest half-word
+ * - other flags in upper half-word(s)
+ */
+#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
+#define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
+#define TIF_SIGPENDING		2	/* signal pending */
+#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
+#define TIF_RESTORE_SIGMASK	4	/* restore signal mask in do_signal() */
+#define TIF_MEMDIE		5	/* is terminating due to OOM killer */
+#define TIF_SYSCALL_TRACEPOINT  6       /* syscall tracepoint instrumentation */
+
+#define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
+#define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
+#define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
+#define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
+
+#define _TIF_WORK_MASK \
+	(_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED)
+
+#endif /* _ASM_RISCV_THREAD_INFO_H */

arch/riscv/include/asm/timex.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_TIMEX_H
+#define _ASM_RISCV_TIMEX_H
+
+#include <asm/param.h>
+
+typedef unsigned long cycles_t;
+
+static inline cycles_t get_cycles(void)
+{
+	cycles_t n;
+
+	__asm__ __volatile__ (
+		"rdtime %0"
+		: "=r" (n));
+	return n;
+}
+
+#ifdef CONFIG_64BIT
+static inline uint64_t get_cycles64(void)
+{
+        return get_cycles();
+}
+#else
+static inline uint64_t get_cycles64(void)
+{
+	u32 lo, hi, tmp;
+	__asm__ __volatile__ (
+		"1:\n"
+		"rdtimeh %0\n"
+		"rdtime %1\n"
+		"rdtimeh %2\n"
+		"bne %0, %2, 1b"
+		: "=&r" (hi), "=&r" (lo), "=&r" (tmp));
+	return ((u64)hi << 32) | lo;
+}
+#endif
+
+#define ARCH_HAS_READ_CURRENT_TIMER
+
+static inline int read_current_timer(unsigned long *timer_val)
+{
+	*timer_val = get_cycles();
+	return 0;
+}
+
+#endif /* _ASM_RISCV_TIMEX_H */

arch/riscv/include/asm/tlb.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_TLB_H
+#define _ASM_RISCV_TLB_H
+
+#include <asm-generic/tlb.h>
+
+static inline void tlb_flush(struct mmu_gather *tlb)
+{
+	flush_tlb_mm(tlb->mm);
+}
+
+#endif /* _ASM_RISCV_TLB_H */

arch/riscv/include/asm/tlbflush.h

+/*
+ * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_TLBFLUSH_H
+#define _ASM_RISCV_TLBFLUSH_H
+
+#ifdef CONFIG_MMU
+
+/* Flush entire local TLB */
+static inline void local_flush_tlb_all(void)
+{
+	__asm__ __volatile__ ("sfence.vma" : : : "memory");
+}
+
+/* Flush one page from local TLB */
+static inline void local_flush_tlb_page(unsigned long addr)
+{
+	__asm__ __volatile__ ("sfence.vma %0" : : "r" (addr) : "memory");
+}
+
+#ifndef CONFIG_SMP
+
+#define flush_tlb_all() local_flush_tlb_all()
+#define flush_tlb_page(vma, addr) local_flush_tlb_page(addr)
+#define flush_tlb_range(vma, start, end) local_flush_tlb_all()
+
+#else /* CONFIG_SMP */
+
+#include <asm/sbi.h>
+
+#define flush_tlb_all() sbi_remote_sfence_vma(0, 0, -1)
+#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
+#define flush_tlb_range(vma, start, end) \
+	sbi_remote_sfence_vma(0, start, (end) - (start))
+
+#endif /* CONFIG_SMP */
+
+/* Flush the TLB entries of the specified mm context */
+static inline void flush_tlb_mm(struct mm_struct *mm)
+{
+	flush_tlb_all();
+}
+
+/* Flush a range of kernel pages */
+static inline void flush_tlb_kernel_range(unsigned long start,
+	unsigned long end)
+{
+	flush_tlb_all();
+}
+
+#endif /* CONFIG_MMU */
+
+#endif /* _ASM_RISCV_TLBFLUSH_H */

arch/riscv/include/asm/unistd.h

+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#define __ARCH_HAVE_MMU
+#define __ARCH_WANT_SYS_CLONE
+#include <uapi/asm/unistd.h>

arch/riscv/kernel/.gitignore

+/vmlinux.lds

arch/riscv/kernel/riscv_ksyms.c

+/*
+ * Copyright (C) 2017 Zihao Yu
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/export.h>
+#include <linux/uaccess.h>
+
+/*
+ * Assembly functions that may be used (directly or indirectly) by modules
+ */
+EXPORT_SYMBOL(__copy_user);

arch/riscv/kernel/vdso/.gitignore

+vdso.lds
+*.tmp