Masahiro Yamada reports that we can fail to set the FW bit in the
auxiliary control register, which enables broadcasting the cache
maintanence operations.  This occurs because we only check that the
SMP/nAMP bit is set, rather than checking whether all the bits we
want to be set are set.

Rearrange the code to ensure that all desired bits are set, and only
update the register if we discover some required bits are not set.
Tested-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

The physical-relative calculation between the XIP text and data sections
introduced by the previous patch was far from obvious. Let's simplify it
by turning it into a macro which takes the two (virtual) addresses.

This allows us to arrange the calculation in a more obvious manner - we
can make it two sub-expressions which calculate the physical address for
each symbol, and then takes the difference of those physical addresses.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When XIP_KERNEL is enabled, the virt to phys address translation for RAM
is not the same as the virt to phys address translation for .text.
The only way to know where physical RAM is located is to use
PLAT_PHYS_OFFSET.
The MACRO will be useful for other places where there is a similar problem.
Signed-off-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NChris Brandt <chris.brandt@renesas.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The proc-v7.S code uses a small temporary stack to preserve register
content in its setup code. This stack is located in the .text section
which is normally meant to be read-only.

Move that temporary stack to the .bss section and get its address in
a position independent way, similarly to what we do in other parts
of the kernel.

While at it, one comments was updated to reflect reality, and the list
of saved registers in the proc-v7.S case is updated to match the comment
next to it for coherency.
Signed-off-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

In cpu_v7_do_suspend routine, r11 is used while it is NOT
saved/restored, different compiler may have different usage
of ARM general registers, so it may cause issues during
calling cpu_v7_do_suspend.

We meet kernel fault occurs when using GCC 4.8.3, r11 contains
valid value before calling into cpu_v7_do_suspend, but when returned
from this routine, r11 is corrupted and lead to kernel fault.
Doing save/restore for those corrupted registers is a must in
assemble code.
Signed-off-by: NAnson Huang <Anson.Huang@freescale.com>
Reviewed-by: NNicolas Pitre <nico@linaro.org>
Cc: <stable@vger.kernel.org> # v3.3+
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We must invalidate the L1 cache before enabling coherency, otherwise
secondary CPUs can inject invalid cache lines into the coherent CPU
cluster, which could then be migrated to other CPUs.  This fixes a
recent regression with SoCFPGA randomly failing to boot.

Fixes: 02b4e275 ("ARM: v7 setup function should invalidate L1 cache")
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Document that r13 is not a stack in the initialisation function, in
case anyone gets other ideas.

Document the registers available for the errata workarounds, and
specifically which registers contain parts of the MIDR register, as
well as which registers must be preserved.

Lastly, use the lowest numbered available register (r0) rather than
r10 for temporary storage.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We already have the main ID register available in r9, there's no need
to refetch it.  Use the saved value.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rather than having a long sprawling __v7_setup function, which is hard
to maintain properly, move the CPU errata out of line.

While doing this, it was discovered that the Cortex-A15 errata had been
incorrectly added:

	ldr	r10, =0x00000c08	@ Cortex-A8 primary part number
	teq	r0, r10
	bne	2f
/* Cortex-A8 errata */
	b	3f
2:	ldr	r10, =0x00000c09	@ Cortex-A9 primary part number
	teq	r0, r10
	bne	3f
/* Cortex-A9 errata */
3:	ldr	r10, =0x00000c0f	@ Cortex-A15 primary part number
	teq	r0, r10
	bne	4f
/* Cortex-A15 errata */
4:

This results in the Cortex-A15 test always being executed after the
Cortex-A8 and Cortex-A9 errata, which is obviously not what is intended.
The 'b 3f' labels should have been updated to 'b 4f'.  The new structure
of:

	/* Cortex-A8 Errata */
	ldr	r10, =0x00000c08	@ Cortex-A8 primary part number
	teq	r0, r10
	beq	__ca8_errata

	/* Cortex-A9 Errata */
	ldr	r10, =0x00000c09	@ Cortex-A9 primary part number
	teq	r0, r10
	beq	__ca9_errata

	/* Cortex-A15 Errata */
	ldr	r10, =0x00000c0f	@ Cortex-A15 primary part number
	teq	r0, r10
	beq	__ca15_errata

__errata_finish:

is much cleaner and easier to see that this kind of thing doesn't
happen.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Re-engineer the LPAE TTBR setup code.  Rather than passing some shifted
address in order to fit in a CPU register, pass either a full physical
address (in the case of r4, r5 for TTBR0) or a PFN (for TTBR1).

This removes the ARCH_PGD_SHIFT hack, and the last dangerous user of
cpu_set_ttbr() in the secondary CPU startup code path (which was there
to re-set TTBR1 to the appropriate high physical address space on
Keystone2.)
Tested-by: NMurali Karicheri <m-karicheri2@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

All ARMv5 and older CPUs invalidate their caches in the early assembly
setup function, prior to enabling the MMU.  This is because the L1
cache should not contain any data relevant to the execution of the
kernel at this point; all data should have been flushed out to memory.

This requirement should also be true for ARMv6 and ARMv7 CPUs - indeed,
these typically do not search their caches when caching is disabled (as
it needs to be when the MMU is disabled) so this change should be safe.

ARMv7 allows there to be CPUs which search their caches while caching is
disabled, and it's permitted that the cache is uninitialised at boot;
for these, the architecture reference manual requires that an
implementation specific code sequence is used immediately after reset
to ensure that the cache is placed into a sane state.  Such
functionality is definitely outside the remit of the Linux kernel, and
must be done by the SoC's firmware before _any_ CPU gets to the Linux
kernel.

Changing the data cache clean+invalidate to a mere invalidate allows us
to get rid of a lot of platform specific hacks around this issue for
their secondary CPU bringup paths - some of which were buggy.
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Tested-by: NFlorian Fainelli <f.fainelli@gmail.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NDinh Nguyen <dinguyen@opensource.altera.com>
Acked-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Tested-by: NThierry Reding <treding@nvidia.com>
Acked-by: NThierry Reding <treding@nvidia.com>
Tested-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Tested-by: NMichal Simek <michal.simek@xilinx.com>
Tested-by: NWei Xu <xuwei5@hisilicon.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Avoid the errata 430973 workaround for non-Cortex A8 CPUs.  Having this
workaround enabled introduces an additional branch target buffer flush
into the context switching path, something we wish to avoid.  To allow
this errata to be enabled in multiplatform kernels while reducing its
impact, rearrange the Cortex-A8 CPU support to avoid impacting on other
Version 7 CPUs.
Tested-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch replaces the 'branch to setup()' instructions embedded
in the PROCINFO structs with the offset to that setup function
relative to the base of the struct. This preserves the position
independent nature of that field, but uses a data item rather
than an instruction.

This is mainly done to prevent linker failures on large kernels,
where the setup function is out of reach for the branch.
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Under extremely rare conditions, in an MPCore node consisting of at
least 3 CPUs, two CPUs trying to perform a STREX to data on the same
shared cache line can enter a livelock situation.

This patch enables the HW mechanism that overcomes the bug. This fixes
the incorrect setup of the STREX backoff delay bit due to a wrong
description in the specification.

Note that enabling the STREX backoff delay mechanism is done by
leaving the bit *cleared*, while the bit was currently being set by
the proc-v7.S code.

[Thomas: adapt to latest mainline, slightly reword the commit log, add
stable markers.]

Fixes: de490193 ("arm: mm: Add support for PJ4B cpu and init routines")

Cc: <stable@vger.kernel.org> # v3.8+
Signed-off-by: NNadav Haklai <nadavh@marvell.com>
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: NJason Cooper <jason@lakedaemon.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Certain versions of the Krait processor don't report that they
support the fused multiply accumulate instruction via the MVFR1
register despite the fact that they actually do. Unfortunately we
use this register to identify support for VFPv4. Override the
hwcap on all Krait processors to indicate support for VFPv4 to
workaround this.
Tested-by: NRob Clark <robdclark@gmail.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The Brahma-B15's ISAR0 correcty advertises UDIV/SDIV support in both ARM
and Thumb2 modes (CPUID_EXT_ISAR0=02101110), so we don't need to
manually apply this hwcap.

The code in question actually predates the following commit, which made
our hwcaps unnecessary:

    commit 8164f7af
    Author: Stephen Boyd <sboyd@codeaurora.org>
    Date:   Mon Mar 18 19:44:15 2013 +0100

        ARM: 7680/1: Detect support for SDIV/UDIV from ISAR0 register
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Perform any CPU-specific initialization required on the
Broadcom Brahma-15 core.
Signed-off-by: NMarc Carino <marc.ceeeee@gmail.com>
Acked-by: NFlorian Fainelli <f.fainelli@gmail.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The CP15 diagnostic register holds ARM errata bits on Cortex-A9, so it
needs to be saved/restored on suspend/resume.  Otherwise, the
effectiveness of errata workaround gets lost together with diagnostic
register bit across suspend/resume cycle.  And the CP15 power control
register of Cortex-A9 shares the same problem.

The patch adds a couple of Cortex-A9 specific suspend/resume functions
to save/restore these two Cortex-A9 CP15 registers across the
suspend/resume cycle.
Signed-off-by: NShawn Guo <shawn.guo@freescale.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Since pj4b suspend/resume routines are implemented based on generic
ARMv7 ones, instead of hard-coding cpu_pj4b_suspend_size, we should have
it be cpu_v7_suspend_size plus pj4b specific bytes.  Otherwise, if
cpu_v7_suspend_size gets updated alone, the pj4b suspend/resume will
likely be broken.

While at it, fix the comments in cpu_pj4b_do_resume, as we're restoring
CP15 registers rather than saving in there.
Signed-off-by: NShawn Guo <shawn.guo@freescale.com>
Acked-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

ARMv6 and greater introduced a new instruction ("bx") which can be used
to return from function calls.  Recent CPUs perform better when the
"bx lr" instruction is used rather than the "mov pc, lr" instruction,
and this sequence is strongly recommended to be used by the ARM
architecture manual (section A.4.1.1).

We provide a new macro "ret" with all its variants for the condition
code which will resolve to the appropriate instruction.

Rather than doing this piecemeal, and miss some instances, change all
the "mov pc" instances to use the new macro, with the exception of
the "movs" instruction and the kprobes code.  This allows us to detect
the "mov pc, lr" case and fix it up - and also gives us the possibility
of deploying this for other registers depending on the CPU selection.
Reported-by: NWill Deacon <will.deacon@arm.com>
Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S
Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood
Tested-by: NShawn Guo <shawn.guo@freescale.com>
Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385
Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci
Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M
Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Cortex-A17 has identical initialisation requirements to Cortex-A12, so
hook it up in proc-v7.S in the same way.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

PJ4B needs extra instructions for suspend and resume, so instead of
using the armv7 version, this commit introduces specific versions for
PJ4B.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The A12 behaves as the A7/A15 does with respect to setting the SMP bit, and
doesn't require TLB ops broadcasting to be explicitly enabled like the A9 does.

Note that as the ACTLR cannot (usually) be written from non-secure, it is the
responsibility of the bootloader/firmware to set this bit per core - it is
done here in Linux as last resort in case of bad firmware.
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJonathan Austin <jonathan.austin@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

During __v{6,7}_setup, we invalidate the TLBs since we are about to
enable the MMU on return to head.S. Unfortunately, without a subsequent
dsb instruction, the invalidation is not guaranteed to have completed by
the time we write to the sctlr, potentially exposing us to junk/stale
translations cached in the TLB.

This patch reworks the init functions so that the dsb used to ensure
completion of cache/predictor maintenance is also used to ensure
completion of the TLB invalidation.

Cc: <stable@vger.kernel.org>
Reported-by: NAlbin Tonnerre <Albin.Tonnerre@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

LPAE enabled kernels use the 64-bit version of TTBR0 and TTBR1
registers. If we're running an LPAE kernel, fill the upper half
of TTBR0 with 0 because we're setting it to the idmap here (the
idmap is guaranteed to be < 4Gb) and fully restore TTBR1 instead
of just restoring the lower 32 bits. Failure to do so can cause
failures on resume from suspend when these registers are only
half restored.
Signed-off-by: NMahesh Sivasubramanian <msivasub@codeaurora.org>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add ARM_BE8() helper to wrap any code conditional on being
compile when CONFIG_ARM_ENDIAN_BE8 is selected and convert
existing places where this is to use it.
Acked-by: NNicolas Pitre <nico@linaro.org>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>

On Cortex-A15 CPUs up to and including r0p4, in certain rare sequences
of code, the loop buffer may deliver incorrect instructions. This
workaround disables the loop buffer to avoid the erratum.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

System-wide barriers aren't required for situations where we only need
to make visibility and ordering guarantees in the inner-shareable domain
(i.e. we are not dealing with devices or potentially incoherent CPUs).

This patch changes the v7 TLB operations, coherent_user_range and
dcache_clean_area functions to user inner-shareable barriers. For cache
maintenance, only the store access type is required to ensure completion.
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Commit ae8a8b95 ("ARM: 7691/1: mm: kill unused TLB_CAN_READ_FROM_L1_CACHE
and use ALT_SMP instead") added early function returns for page table
cache flushing operations on ARMv7 SMP CPUs.

Unfortunately, when targetting Thumb-2, these `mov pc, lr' sequences
assemble to 2 bytes which can lead to corruption of the instruction
stream after code patching.

This patch fixes the alternates to use wide (32-bit) instructions for
Thumb-2, therefore ensuring that the patching code works correctly.

Cc: <stable@vger.kernel.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit  -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings.  In any case, they are temporary and harmless.

This removes all the ARM uses of the __cpuinit macros from C code,
and all __CPUINIT from assembly code.  It also had two ".previous"
section statements that were paired off against __CPUINIT
(aka .section ".cpuinit.text") that also get removed here.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

This commit fixes the regression on Armada 370 (the kernal hang during
boot) introduced by the commit: "ARM: 7691/1: mm: kill unused
TLB_CAN_READ_FROM_L1_CACHE and use ALT_SMP instead".

When coming out of either a Wait for Interrupt (WFI) or a Wait for
Event (WFE) IDLE states, a specific timing sensitivity exists between
the retiring WFI/WFE instructions and the newly issued subsequent
instructions. This sensitivity can result in a CPU hang scenario.  The
workaround is to insert either a Data Synchronization Barrier (DSB) or
Data Memory Barrier (DMB) command immediately after the WFI/WFE
instruction.

This commit was based on the work of Lior Amsalem, but heavily
modified to apply the errata fix dynamically according to the
processor type thanks to the suggestions of Russell King and Nicolas
Pitre.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Tested-by: NWilly Tarreau <w@1wt.eu>
Cc: <stable@vger.kernel.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This commit fixes the ID and mask for the PJ4B which was too
restrictive and didn't match the CPU of the Armada 370 SoC.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch adds processor info for ARM Ltd. Cortex-R7.

The R7 has many similarities to the A9 and though the ACTLR layout is not
identical, the bits associated with cache operations broadcasting and SMP
modes are the same for A9, A5 and R7 (Though in the A-class processors the
same bits toggle TLB-ops broadcasting as well as cache-ops)
Signed-off-by: NJonathan Austin <jonathan.austin@arm.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Stephen Boyd <sboyd@codeaurora.org>

The ARM CPU suspend code can be selected even for a !CONFIG_MMU
configuration. The resulting kernel will not compile and, even if it did,
would access undefined co-processor registers when executing.

This patch fixes the v6 and v7 CPU suspend code for the nommu case.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Tested-by: NJonathan Austin <jonathan.austin@arm.com>
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> (commit_signer:1/3=33%)
CC: Santosh Shilimkar <santosh.shilimkar@ti.com> (commit_signer:1/3=33%)
CC: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

pj4b cpus are LPAE capable so enable them on LPAE compilations
Signed-off-by: NLior Amsalem <alior@marvell.com>
Tested-by: NFranklin <flin@marvell.com>
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Many ARMv7 cores have hardware page table walkers that can read the L1
cache. This is discoverable from the ID_MMFR3 register, although this
can be expensive to access from the low-level set_pte functions and is a
pain to cache, particularly with multi-cluster systems.

A useful observation is that the multi-processing extensions for ARMv7
require coherent table walks, meaning that we can make use of ALT_SMP
patching in proc-v7-* to patch away the cache flush safely for these
cores.
Reported-by: NAlbin Tonnerre <Albin.Tonnerre@arm.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Some early versions of the Krait CPU design incorrectly indicate
that they only support the UDIV and SDIV instructions in Thumb
mode when they actually support them in ARM and Thumb mode. It
seems that these CPUs follow the DDI0406B ARM ARM which has two
possible values for the divide instructions field, instead of the
DDI0406C document which has three possible values.

Work around this problem by checking the MIDR against Krait CPUs
with this faulty ISAR0 register and force the hwcaps to indicate
support in both modes.

[sboyd: Rewrote commit text to reflect real reasoning now that
	we autodetect udiv/sdiv]
Signed-off-by: NStepan Moskovchenko <stepanm@codeaurora.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The ISAR0 register indicates support for the SDIV and UDIV
instructions in both the Thumb and ARM instruction set. Read the
register to detect the supported instructions and update the
elf_hwcap mask as appropriate. This is better than adding more
and more cpuid checks in proc-v7.S for each new cpu variant that
supports these instructions.
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

If CONFIG_ARCH_MULTIPLATFORM & CONFIG_ARCH_MVEBU are both enabled,
__v7_pj4b_setup is added between __v7_ca9mp_setup and __v7_setup.

But there's no jump instruction added. If the chip is Cortex A5/A9,
it goes through __v7_pj4b_setup also. It results in system hang.
Signed-off-by: NHaojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

In order to support secure and non-secure platforms in multi-platform
kernels, errata work-arounds that access secure only registers need to
be disabled. Make all the errata options that fit in this category
depend on !CONFIG_ARCH_MULTIPLATFORM.

This will effectively remove the errata options as platforms are
converted over to multi-platform.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>