1. 03 Dec, 2018 1 commit
    • Mathieu Malaterre's avatar
      mips: annotate implicit fall throughs · 69095e39
      Mathieu Malaterre authored
      There is a plan to build the kernel with -Wimplicit-fallthrough and
      these places in the code produced warnings. Fix them up.
      
      This patch produces no change in behaviour, but should be reviewed in
      case these are actually bugs not intentional fallthoughs.
      Signed-off-by: default avatarMathieu Malaterre <malat@debian.org>
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Cc: Kees Cook <keescook@google.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: linux-mips@vger.kernel.org
      Cc: linux-kernel@vger.kernel.org
      69095e39
  2. 27 Nov, 2018 2 commits
  3. 22 Nov, 2018 1 commit
    • Paul Burton's avatar
      MIPS: Only include mmzone.h when CONFIG_NEED_MULTIPLE_NODES=y · 66a4059b
      Paul Burton authored
      MIPS' asm/mmzone.h includes the machine/platform mmzone.h
      unconditionally, but since commit bb53fdf3 ("MIPS: c-r4k: Add
      r4k_blast_scache_node for Loongson-3") is included by asm/rk4cache.h for
      all r4k-style configs regardless of CONFIG_NEED_MULTIPLE_NODES.
      
      This is problematic when CONFIG_NEED_MULTIPLE_NODES=n because both the
      loongson3 & ip27 mmzone.h headers unconditionally define the NODE_DATA
      preprocessor macro which is aready defined by linux/mmzone.h, resulting
      in the following build error:
      
        In file included from ./arch/mips/include/asm/mmzone.h:10,
                         from ./arch/mips/include/asm/r4kcache.h:23,
                         from arch/mips/mm/c-r4k.c:33:
        ./arch/mips/include/asm/mach-loongson64/mmzone.h:48: error: "NODE_DATA" redefined [-Werror]
         #define NODE_DATA(n)  (&__node_data[(n)]->pglist)
      
        In file included from ./include/linux/topology.h:32,
                         from ./include/linux/irq.h:19,
                         from ./include/asm-generic/hardirq.h:13,
                         from ./arch/mips/include/asm/hardirq.h:16,
                         from ./include/linux/hardirq.h:9,
                         from arch/mips/mm/c-r4k.c:11:
        ./include/linux/mmzone.h:907: note: this is the location of the previous definition
         #define NODE_DATA(nid)  (&contig_page_data)
      
      Resolve this by only including the machine mmzone.h when
      CONFIG_NEED_MULTIPLE_NODES=y, which also removes the need for the empty
      mach-generic version of the header which we delete.
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Fixes: bb53fdf3 ("MIPS: c-r4k: Add r4k_blast_scache_node for Loongson-3")
      66a4059b
  4. 21 Nov, 2018 31 commits
  5. 20 Nov, 2018 1 commit
  6. 19 Nov, 2018 3 commits
  7. 15 Nov, 2018 1 commit
    • Maciej W. Rozycki's avatar
      MIPS: SiByte: Enable swiotlb for SWARM, LittleSur and BigSur · e4849aff
      Maciej W. Rozycki authored
      The Broadcom SiByte BCM1250, BCM1125, and BCM1125H SOCs have an onchip
      DRAM controller that supports memory amounts of up to 16GiB, and due to
      how the address decoder has been wired in the SOC any memory beyond 1GiB
      is actually mapped starting from 4GiB physical up, that is beyond the
      32-bit addressable limit[1].  Consequently if the maximum amount of
      memory has been installed, then it will span up to 19GiB.
      
      Many of the evaluation boards we support that are based on one of these
      SOCs have their memory soldered and the amount present fits in the
      32-bit address range.  The BCM91250A SWARM board however has actual DIMM
      slots and accepts, depending on the peripherals revision of the SOC, up
      to 4GiB or 8GiB of memory in commercially available JEDEC modules[2].
      I believe this is also the case with the BCM91250C2 LittleSur board.
      This means that up to either 3GiB or 7GiB of memory requires 64-bit
      addressing to access.
      
      I believe the BCM91480B BigSur board, which has the BCM1480 SOC instead,
      accepts at least as much memory, although I have no documentation or
      actual hardware available to verify that.
      
      Both systems have PCI slots installed for use by any PCI option boards,
      including ones that only support 32-bit addressing (additionally the
      32-bit PCI host bridge of the BCM1250, BCM1125, and BCM1125H SOCs limits
      addressing to 32-bits), and there is no IOMMU available.  Therefore for
      PCI DMA to work in the presence of memory beyond enable swiotlb for the
      affected systems.
      
      All the other SOC onchip DMA devices use 40-bit addressing and therefore
      can address the whole memory, so only enable swiotlb if PCI support and
      support for DMA beyond 4GiB have been both enabled in the configuration
      of the kernel.
      
      This shows up as follows:
      
      Broadcom SiByte BCM1250 B2 @ 800 MHz (SB1 rev 2)
      Board type: SiByte BCM91250A (SWARM)
      Determined physical RAM map:
       memory: 000000000fe7fe00 @ 0000000000000000 (usable)
       memory: 000000001ffffe00 @ 0000000080000000 (usable)
       memory: 000000000ffffe00 @ 00000000c0000000 (usable)
       memory: 0000000087fffe00 @ 0000000100000000 (usable)
      software IO TLB: mapped [mem 0xcbffc000-0xcfffc000] (64MB)
      
      in the bootstrap log and removes failures like these:
      
      defxx 0000:02:00.0: dma_direct_map_page: overflow 0x0000000185bc6080+4608 of device mask ffffffff bus mask 0
      fddi0: Receive buffer allocation failed
      fddi0: Adapter open failed!
      IP-Config: Failed to open fddi0
      defxx 0000:09:08.0: dma_direct_map_page: overflow 0x0000000185bc6080+4608 of device mask ffffffff bus mask 0
      fddi1: Receive buffer allocation failed
      fddi1: Adapter open failed!
      IP-Config: Failed to open fddi1
      
      when memory beyond 4GiB is handed out to devices that can only do 32-bit
      addressing.
      
      This updates commit cce335ae ("[MIPS] 64-bit Sibyte kernels need
      DMA32.").
      
      References:
      
      [1] "BCM1250/BCM1125/BCM1125H User Manual", Revision 1250_1125-UM100-R,
          Broadcom Corporation, 21 Oct 2002, Section 3: "System Overview",
          "Memory Map", pp. 34-38
      
      [2] "BCM91250A User Manual", Revision 91250A-UM100-R, Broadcom
          Corporation, 18 May 2004, Section 3: "Physical Description",
          "Supported DRAM", p. 23
      Signed-off-by: default avatarMaciej W. Rozycki <macro@linux-mips.org>
      [paul.burton@mips.com: Remove GPL text from dma.c; SPDX tag covers it]
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Patchwork: https://patchwork.linux-mips.org/patch/21108/
      References: cce335ae ("[MIPS] 64-bit Sibyte kernels need DMA32.")
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: linux-mips@linux-mips.org
      Cc: linux-kernel@vger.kernel.org
      e4849aff