adapt the DIU clock initialization to the COMMON_CLK approach:
device tree based clock lookup, prepare and unprepare for clocks,
work with frequencies not dividers, call the appropriate clk_*()
routines and don't access CCM registers

the "best clock" determination now completely relies on the
platform's clock driver to pick a frequency close to what the
caller requests, and merely checks whether the desired frequency
was met (fits the tolerance of the monitor)

this approach shall succeed upon first try in the usual case,
will test a few less desirable yet acceptable frequencies in
edge cases, and will fallback to "best effort" if none of the
previously tried frequencies pass the test

provide a fallback clock lookup approach in case the OF based clock
lookup for the DIU fails, this allows for successful operation in
the presence of an outdated device tree which lacks clock specs

Cc: Anatolij Gustschin <agust@denx.de>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

transition to the common clock framework has completed and the PPC_CLOCK
is no longer available for the MPC512x platform, remove the now obsolete
code path of the mpc5xxx mscan driver which accessed clock control module
registers directly

Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: linux-can@vger.kernel.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

implement a .get_clock() callback for the MPC512x platform which uses
the common clock infrastructure (eliminating direct access to the clock
control registers from within the CAN network driver), and provide the
corresponding .put_clock() callback to release resources after use

acquire both the clock items for register access ("ipg") as well as for
wire communication ("can")

keep the previous implementation of MPC512x support in place during
migration, this results in a readable diff of the change

this change is neutral to the MPC5200 platform

Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: linux-can@vger.kernel.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

after device tree based clock lookup became available, the VIU driver
need no longer use the previous global "viu_clk" name, but should use
the "ipg" clock name specific to the OF node

Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
Cc: linux-media@vger.kernel.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

after device tree based clock lookup became available, the NAND
flash driver need no longer use the previous global "nfc_clk" name,
but should use the "ipg" clock name specific to the OF node

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

after device tree based clock lookup became available, the peripheral
driver need no longer construct clock names which include the component
index -- remove the "usb%d_clk" template, always use "ipg" instead

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

prepare and enable the FIFO clock upon PSC FIFO initialization,
check for and propagage errors when enabling the PSC FIFO clock,
disable and unprepare the FIFO clock upon PSC FIFO uninitialization

devm_{get,put}_clk() doesn't apply here, as the SoC provides a
single FIFO component which is shared among several PSC components,
thus the FIFO isn't associated with a device (while the PSCs are)

provide a fallback clock lookup approach in case the OF based clock
lookup for the PSC FIFO fails, this allows for successful operation in
the presence of an outdated device tree which lacks clock specs

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

after device tree based clock lookup became available, the peripheral
driver need no longer construct clock names which include the PSC index,
remove the "psc%d_mclk" template and unconditionally use 'mclk'

acquire and release the "ipg" clock item for register access as well

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

after device tree based clock lookup became available, the peripheral
driver need no longer construct clock names which include the PSC index,
remove the "psc%d_mclk" template and unconditionally use 'mclk'

acquire and release the 'ipg' clock item for register access as well

Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Acked-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

the setup before the change was
- arch/powerpc/Kconfig had the PPC_CLOCK option, off by default
- depending on the PPC_CLOCK option the arch/powerpc/kernel/clock.c file
  was built, which implements the clk.h API but always returns -ENOSYS
  unless a platform registers specific callbacks
- the MPC52xx platform selected PPC_CLOCK but did not register any
  callbacks, thus all clk.h API calls keep resulting in -ENOSYS errors
  (which is OK, all peripheral drivers deal with the situation)
- the MPC512x platform selected PPC_CLOCK and registered specific
  callbacks implemented in arch/powerpc/platforms/512x/clock.c, thus
  provided real support for the clock API
- no other powerpc platform did select PPC_CLOCK

the situation after the change is
- the MPC512x platform implements the COMMON_CLK interface, and thus the
  PPC_CLOCK approach in arch/powerpc/platforms/512x/clock.c has become
  obsolete
- the MPC52xx platform still lacks genuine support for the clk.h API
  while this is not a change against the previous situation (the error
  code returned from COMMON_CLK stubs differs but every call still
  results in an error)
- with all references gone, the arch/powerpc/kernel/clock.c wrapper and
  the PPC_CLOCK option have become obsolete, as did the clk_interface.h
  header file

the switch from PPC_CLOCK to COMMON_CLK is done for all platforms within
the same commit such that multiplatform kernels (the combination of 512x
and 52xx within one executable) keep working

Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

this addresses the client side of device tree based clock lookups

add clock specifiers to the mbx, nfc, mscan, sdhc, i2c, axe, diu, viu,
mdio, fec, usb, pata, psc, psc fifo, and pci nodes in the shared
mpc5121.dtsi include

Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: devicetree@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

extend the recently added COMMON_CLK platform support for MPC512x such
that it works with incomplete device tree data which lacks clock specs

Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
[agust@denx.de: moved node macro definitions out of the function body]
Signed-off-by: Anatolij Gustschin <agust@denx.de>

this change implements a clock driver for the MPC512x PowerPC platform
which follows the COMMON_CLK approach and uses common clock drivers
shared with other platforms

this driver implements the publicly announced set of clocks (those
listed in the dt-bindings header file), as well as generates additional
'struct clk' items where the SoC hardware cannot easily get mapped to
the common primitives (shared code) of the clock API, or requires
"intermediate clock nodes" to represent clocks that have both gates and
dividers

the previous PPC_CLOCK implementation is kept in place and remains
active for the moment, the newly introduced CCF clock driver will
receive additional support for backwards compatibility in a subsequent
patch before it gets enabled and will replace the PPC_CLOCK approach

some of the clock items get pre-enabled in the clock driver to not have
them automatically disabled by the underlying clock subsystem because of
their being unused -- this approach is desirable because
- some of the clocks are useful to have for diagnostics and information
  despite their not getting claimed by any drivers (CPU, internal and
  external RAM, internal busses, boot media)
- some of the clocks aren't claimed by their peripheral drivers yet,
  either because of missing driver support or because device tree specs
  aren't available yet (but the workarounds will get removed as the
  drivers get adjusted and the device tree provides the clock specs)

clkdev registration provides "alias names" for few clock items
- to not break those peripheral drivers which encode their component
  index into the name that is used for clock lookup (UART, SPI, USB)
- to not break those drivers which use names for the clock lookup which
  were encoded in the previous PPC_CLOCK implementation (NFC, VIU, CAN)
this workaround will get removed as these drivers get adjusted after
device tree based clock lookup has become available

the COMMON_CLK implementation copes with device trees which lack an
oscillator node (backwards compat), the REF clock is then derived from
the IPS bus frequency and multiplier values fetched from hardware

Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

this addresses the clock driver aka provider's side of clocks
- introduce a 'clocks' subtree with an 'osc' node for the crystal
  or oscillator SoC input (fixed frequency)
- the 'clock@f00' clock-control-module node references the 'osc' for
  its input, and is another provider for all the clocks which the
  CCM component manages
- prepare for future references to clocks from peripheral nodes
  by means of the <&clks ID> syntax and symbolic ID names which a
  header file provides
- provide default values with 33MHz oscillator frequency in the
  common include (the 66MHz IPS bus already was there), and add
  override values for the ifm AC14xx board which deviates from
  the reference design (25MHz xtal, 80MHz IPS bus)

Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: devicetree@vger.kernel.org
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

introduce a dt-bindings/ header file for MPC512x clocks,
providing symbolic identifiers for those SoC clocks which
clients will reference from their device tree nodes

Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: devicetree@vger.kernel.org
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

Merge a pile of fixes that went into the "merge" branch (3.13-rc's) such
as Anton Little Endian fixes.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The SLB save area is shared with the hypervisor and is defined
as big endian, so we need to byte swap on little endian builds.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Anatolij writes:

Please pull two DTS fixes for MPC5125 tower board. Without
them the v3.13-rcX kernels do not boot.

This patch updates the generic iommu backend code to use the
it_page_shift field to determine the iommu page size instead of
using hardcoded values.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This patch adds a it_page_shift field to struct iommu_table and
initiliases it to 4K for all platforms.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The powerpc iommu uses a hardcoded page size of 4K. This patch changes
the name of the IOMMU_PAGE_* macros to reflect the hardcoded values. A
future patch will use the existing names to support dynamic page
sizes.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This removes the REDBOOT Kconfig parameter,
which was no longer used anywhere in the source code
and Makefiles.
Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

With recent machine check patch series changes, The exception vectors
starting from 0x4300 are now overflowing with allyesconfig. Fix that by
moving machine_check_common and machine_check_handle_early code out of
that region to make enough room for exception vector area.

Fixes this build error reportes by Stephen:

arch/powerpc/kernel/exceptions-64s.S: Assembler messages:
arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards
arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards

[Moved the code further down as it introduced link errors due to too long
 relative branches to the masked interrupts handlers from the exception
 prologs. Also removed the useless feature section --BenH
]
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Commit 5c0484e2 ('powerpc: Endian safe trampoline') resulted in
losing proper alignment of the spinlock variables used when booting
secondary CPUs, causing some quite odd issues with failing to boot on
PA Semi-based systems.

This showed itself on ppc64_defconfig, but not on pasemi_defconfig,
so it had gone unnoticed when I initially tested the LE patch set.

Fix is to add explicit alignment instead of relying on good luck. :)

[ It appears that there is a different issue with PA Semi systems
  however this fix is definitely correct so applying anyway -- BenH
]

Fixes: 5c0484e2 ('powerpc: Endian safe trampoline')
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=67811Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

p_end is an 8 byte value embedded in the text section. This means it
is only 4 byte aligned when it should be 8 byte aligned. Fix this
by adding an explicit alignment.

This fixes an issue where POWER7 little endian builds with
CONFIG_RELOCATABLE=y fail to boot.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Prevent ioda_eeh_hub_diag() from clobbering itself when called by supplying
a per-PHB buffer for P7IOC hub diagnostic data.  Take care to inform OPAL of
the correct size for the buffer.

[Small style change to the use of sizeof -- BenH]
Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

PHB diagnostic buffer may be smaller than PAGE_SIZE, especially when
PAGE_SIZE > 4KB.
Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The powerpc 64-bit __copy_tofrom_user() function uses shifts to handle
unaligned invocations.  However, these shifts were designed for
big-endian systems: On little-endian systems, they must shift in the
opposite direction.

This commit relies on the C preprocessor to insert the correct shifts
into the assembly code.

[ This is a rare but nasty LE issue. Most of the time we use the POWER7
optimised __copy_tofrom_user_power7 loop, but when it hits an exception
we fall back to the base __copy_tofrom_user loop. - Anton ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The generic put_unaligned/get_unaligned macros were made endian-safe by
calling the appropriate endian dependent macros based on the endian type
of the powerpc processor.
Signed-off-by: Rajesh B Prathipati <rprathip@linux.vnet.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

In EXCEPTION_PROLOG_COMMON() we check to see if the stack pointer (r1)
is valid when coming from the kernel.  If it's not valid, we die but
with a nice oops message.

Currently we allocate a stack frame (subtract INT_FRAME_SIZE) before we
check to see if the stack pointer is negative.  Unfortunately, this
won't detect a bad stack where r1 is less than INT_FRAME_SIZE.

This patch fixes the check to compare the modified r1 with
-INT_FRAME_SIZE.  With this, bad kernel stack pointers (including NULL
pointers) are correctly detected again.

Kudos to Paulus for finding this.
Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@vger.kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

At the moment the USB controller's pin muxing is not setup
correctly and causes a kernel panic upon system startup, so
disable the USB1 device tree node in the MPC5125 tower board
dts file.

The USB controller is connected to an USB3320 ULPI transceiver
and the device tree should receive an update to reflect correct
dependencies and required initialization data before the USB1
node can get re-enabled.
Signed-off-by: Matteo Facchinetti <matteo.facchinetti@sirius-es.it>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

the 'soc' node in the MPC5125 "tower" board .dts has an '#interrupt-cells'
property although this node is not an interrupt controller

remove this erroneously placed property because starting with v3.13-rc1
lookup and resolution of 'interrupts' specs for peripherals gets misled
(tries to use the 'soc' as the interrupt parent which fails), emits
'no irq domain found' WARN() messages and breaks the boot process

[ best viewed with 'git diff -U5' to have DT node names in the context ]

Cc: Anatolij Gustschin <agust@denx.de>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

We are passing pointers to the firmware for reads, we need to properly
convert the result as OPAL is always BE.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

opal_xscom_read uses a pointer to return the data so we need
to byteswap it on LE builds.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

A couple more device tree properties that need byte swapping.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The MSI code is miscalculating quotas in little endian mode.
Add required byteswaps to fix this.

Before we claimed a quota of 65536, after the patch we
see the correct value of 256.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

We need to byteswap ibm,pcie-link-speed-stats.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The NVRAM code has a number of endian issues. I noticed a very
confused error log count:

RTAS: 100663330 -------- RTAS event begin --------

100663330 == 0x06000022. 0x6 LE error logs and 0x22 BE error logs.

The pstore code has similar issues - if we write an oops in one
endian and attempt to read it in another we get junk.

Make both of these formats big endian, and byteswap as required.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Some obvious issues:

cat /proc/ppc64/lparcfg
...
partition_id=16777216
...
partition_potential_processors=268435456
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

cpu_to_core_id() is missing a byteswap:

cat /sys/devices/system/cpu/cpu63/topology/core_id
201326592
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>