Some architectures like xscale and feroceon have cache API variants that
map cache flushing functions as aliases to the base architecture.
This patch adds the required aliases to complete the implementation of
cache flushing LoUIS API.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

ARM v7 architecture introduced the concept of cache levels and related
control registers. New processors like A7 and A15 embed an L2 unified cache
controller that becomes part of the cache level hierarchy. Some operations in
the kernel like cpu_suspend and __cpu_disable do not require a flush of the
entire cache hierarchy to DRAM but just the cache levels belonging to the
Level of Unification Inner Shareable (LoUIS), which in most of ARM v7 systems
correspond to L1.

The current cache flushing API used in cpu_suspend and __cpu_disable,
flush_cache_all(), ends up flushing the whole cache hierarchy since for
v7 it cleans and invalidates all cache levels up to Level of Coherency
(LoC) which cripples system performance when used in hot paths like hotplug
and cpuidle.

Therefore a new kernel cache maintenance API must be added to cope with
latest ARM system requirements.

This patch adds flush_cache_louis() to the ARM kernel cache maintenance API.

This function cleans and invalidates all data cache levels up to the
Level of Unification Inner Shareable (LoUIS) and invalidates the instruction
cache for processors that support it (> v7).

This patch also creates an alias of the cache LoUIS function to flush_kern_all
for all processor versions prior to v7, so that the current cache flushing
behaviour is unchanged for those processors.

v7 cache maintenance code implements a cache LoUIS function that cleans and
invalidates the D-cache up to LoUIS and invalidates the I-cache, according
to the new API.
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>

The CPU reset functions disable the MMU and therefore must be executed
with an identity mapping in place.

This patch places the CPU reset functions into the .idmap.text section,
causing the idmap code to include them as part of the identity mapping.
Acked-by: NDave Martin <dave.martin@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Only use the preallocated page table during the resume, not while
suspending.  This avoids the overhead of having to switch unnecessarily
to the resume page table in the suspend path.
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Preallocate a page table and setup an identity mapping for the MMU
enable code.  This means we don't have to "borrow" a page table to
do this, avoiding complexities with L2 cache coherency.
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Commit 66a625a8 (ARM: mm: proc-macros: Add generic proc/cache/tlb struct
definition macros) introduced build errors when PM_SLEEP is not enabled.
The per-CPU do_suspend/do_resume functions are defined via the
preprocessor to constant 0.  However, the macros which use these were
converted to assembly, resulting in undefined references to these
functions.  Fix that by moving the ! ifdef section into proc-macros.S
and deleting it from all effected proc-*.S files.
Acked-by: NDave Martin <dave.martin@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Without this patch, xscale_80200_A0_A1 is missing the
icache_flush_all entry, which would result in the wrong functions
being called at run-time.

This patch re-uses xscale_icache_flush_all for
xscale_80200_A0_A1_cache_fns.
Signed-off-by: NDave Martin <dave.martin@linaro.org>

gas used to accept (and ignore?) .size directives which referred to
undefined symbols, as this does.  In binutils 2.21 these are treated
as fatal errors.
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NEric Miao <eric.y.miao@gmail.com>

CONFIG_PM is now set whenever we support either runtime PM in addition
to suspend and hibernate.  This causes build errors when runtime PM is
enabled on a platform, but the CPU does not have the appropriate support
for suspend.

So, switch this code to use CONFIG_PM_SLEEP rather than CONFIG_PM to
allow runtime PM to be enabled without causing build errors.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This adds core support for saving and restoring CPU coprocessor
registers for suspend/resume support.  This contains support for suspend
with ARM920, ARM926, SA11x0, PXA25x, PXA27x, PXA3xx, V6 and V7 CPUs.
Tested on Assabet and Tegra 2.
Tested-by: NColin Cross <ccross@android.com>
Tested-by: NKukjin Kim <kgene.kim@samsung.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Commit 81d11955 ("ARM: 6405/1: Handle __flush_icache_all for
CONFIG_SMP_ON_UP") added a new function to struct cpu_cache_fns:
flush_icache_all(). It also implemented this for v6 and v7 but not
for v5 and backwards. Without the function pointer in place, we
will be calling wrong cache functions.

For example with ep93xx we get following:

    Unable to handle kernel paging request at virtual address ee070f38
    pgd = c0004000
    [ee070f38] *pgd=00000000
    Internal error: Oops: 80000005 [#1] PREEMPT
    last sysfs file:
    Modules linked in:
    CPU: 0    Not tainted  (2.6.36+ #1)
    PC is at 0xee070f38
    LR is at __dma_alloc+0x11c/0x2d0
    pc : [<ee070f38>]    lr : [<c0032c8c>]    psr: 60000013
    sp : c581bde0  ip : 00000000  fp : c0472000
    r10: c0472000  r9 : 000000d0  r8 : 00020000
    r7 : 0001ffff  r6 : 00000000  r5 : c0472400  r4 : c5980000
    r3 : c03ab7e0  r2 : 00000000  r1 : c59a0000  r0 : c5980000
    Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
    Control: c000717f  Table: c0004000  DAC: 00000017
    Process swapper (pid: 1, stack limit = 0xc581a270)
    [<c0032c8c>] (__dma_alloc+0x11c/0x2d0)
    [<c0032e5c>] (dma_alloc_writecombine+0x1c/0x24)
    [<c0204148>] (ep93xx_pcm_preallocate_dma_buffer+0x44/0x60)
    [<c02041c0>] (ep93xx_pcm_new+0x5c/0x88)
    [<c01ff188>] (snd_soc_instantiate_cards+0x8a8/0xbc0)
    [<c01ff59c>] (soc_probe+0xfc/0x134)
    [<c01adafc>] (platform_drv_probe+0x18/0x1c)
    [<c01acca4>] (driver_probe_device+0xb0/0x16c)
    [<c01ac284>] (bus_for_each_drv+0x48/0x84)
    [<c01ace90>] (device_attach+0x50/0x68)
    [<c01ac0f8>] (bus_probe_device+0x24/0x44)
    [<c01aad7c>] (device_add+0x2fc/0x44c)
    [<c01adfa8>] (platform_device_add+0x104/0x15c)
    [<c0015eb8>] (simone_init+0x60/0x94)
    [<c0021410>] (do_one_initcall+0xd0/0x1a4)

__dma_alloc() calls (inlined) __dma_alloc_buffer() which ends up
calling dmac_flush_range(). Now since the entries in the
arm920_cache_fns are shifted by one, we jump into address 0xee070f38
which is actually next instruction after the arm920_cache_fns
structure.

So implement flush_icache_all() for the rest of the supported CPUs
using a generic 'invalidate I cache' instruction.
Signed-off-by: NMika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When hotplug CPU is enabled, we need to keep the list of supported CPUs,
their setup functions, and __lookup_processor_type in place so that we
can find and initialize secondary CPUs.  Move these into the __CPUINIT
section.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

All implementations of cpu_proc_fin() start by disabling interrupts
and then flush caches.  Rather than have every processors proc_fin()
implementation do this, move it out into generic code - and move the
cache flush past setup_mm_for_reboot() (so it can benefit from having
caches still enabled.)

This allows cpu_proc_fin() to become independent of the L1/L2 cache
types, and eventually move the L2 cache flushing into the L2 support
code.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

These are now unused, and so can be removed.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-By: NSantosh Shilimkar <santosh.shilimkar@ti.com>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Tested-By: NSantosh Shilimkar <santosh.shilimkar@ti.com>

... and rename the function since it no longer operates on just
pages.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Instruction fault status register, IFSR, was introduced on ARMv6 to
provide status information about the last insturction fault. It
needed for proper prefetch abort handling.

Now we have three prefetch abort model:

  * legacy - for CPUs before ARMv6. They doesn't provide neither
    IFSR nor IFAR. We simulate IFSR with section translation fault
    status for them to generalize code;
  * ARMv6 - provides IFSR, but not IFAR;
  * ARMv7 - provides both IFSR and IFAR.
Signed-off-by: NKirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Due to problems at cam.org, my nico@cam.org email address is no longer
valid.  FRom now on, nico@fluxnic.net should be used instead.
Signed-off-by: NNicolas Pitre <nico@fluxnic.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

asm code really wants asm/hwcap.h, so include that instead.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

As of the previous commit, MT_DEVICE_IXP2000 encodes to the same
PTE bit encoding as MT_DEVICE, so it's now redundant.  Convert
MT_DEVICE_IXP2000 to use MT_DEVICE instead, and remove its aliases.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Use 'shared device' mappings for devices, and use the standard
bit combinations for Xscale3.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

There are actually only four separate implementations of set_pte_ext.
Use assembler macros to insert code for these into the proc-*.S files.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The proc-*.S files have the _prefetch_abort pointer placed at the end
of the processor structure but the cpu-multi32.h defines it in the
second position. The patch also fixes the support for XSC3 and the
MMU-less CPUs (740, 7tdmi, 940, 946 and 9tdmi).
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch adds a prefetch abort handler similar to the data abort one
and renames the latter for consistency. Initial implementation by Paul
Brook with some renaming by Catalin Marinas.
Signed-off-by: NPaul Brook <paul@codesourcery.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Some bootloaders are disabling write buffer coalescing. Enable it back
under linux.
Signed-off-by: NArnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add Intel KIXRP435 Reference Platform based on IXP43x processor.
Fixed after review : access to cp15 removed in identification functions,
used access to global processor_id instead
Signed-off-by: NVladimir Barinov <vbarinov@ru.mvista.com>
Signed-off-by: NRuslan  Sushko <rsushko@ru.mvista.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

cosmetic fix so iop333 is not reported as ixp46x
iop333 cpuid = 0x69054210
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

L_PTE_ASID is not really required to be stored in every PTE, since we
can identify it via the address passed to set_pte_at().  So, create
set_pte_ext() which takes the address of the PTE to set, the Linux
PTE value, and the additional CPU PTE bits which aren't encoded in
the Linux PTE value.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

XScale cores either have a DSP coprocessor (which contains a single
40 bit accumulator register), or an iWMMXt coprocessor (which contains
eight 64 bit registers.)

Because of the small amount of state in the DSP coprocessor, access to
the DSP coprocessor (CP0) is always enabled, and DSP context switching
is done unconditionally on every task switch.  Access to the iWMMXt
coprocessor (CP0/CP1) is enabled only when an iWMMXt instruction is
first issued, and iWMMXt context switching is done lazily.

CONFIG_IWMMXT is supposed to mean 'the cpu we will be running on will
have iWMMXt support', but boards are supposed to select this config
symbol by hand, and at least one pxa27x board doesn't get this right,
so on that board, proc-xscale.S will incorrectly assume that we have a
DSP coprocessor, enable CP0 on boot, and we will then only save the
first iWMMXt register (wR0) on context switches, which is Bad.

This patch redefines CONFIG_IWMMXT as 'the cpu we will be running on
might have iWMMXt support, and we will enable iWMMXt context switching
if it does.'  This means that with this patch, running a CONFIG_IWMMXT=n
kernel on an iWMMXt-capable CPU will no longer potentially corrupt iWMMXt
state over context switches, and running a CONFIG_IWMMXT=y kernel on a
non-iWMMXt capable CPU will still do DSP context save/restore.

These changes should make iWMMXt work on PXA3xx, and as a side effect,
enable proper acc0 save/restore on non-iWMMXt capable xsc3 cores such
as IOP13xx and IXP23xx (which will not have CONFIG_CPU_XSCALE defined),
as well as setting and using HWCAP_IWMMXT properly.
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

These files want to provide/access ELF hwcap information, so should
be including asm/elf.h rather than asm/procinfo.h
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

ARM patch 3756/1 added HWCAP_IWMMXT.  This patch adds support
for broadcasting that info via /proc/cpuinfo and sets it for
the CPU features of the PXA270.

I've booted 19rc3 on a pxa270 and confirmed that the /proc/cpuinfo
shows "iwmmxt" in the Features.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NNicolas Pitre <nico@cam.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

On stepping A0/A1 of the 80200, invalidating D-cache by line doesn't
clear the dirty bits, which means that if we invalidate a dirty line,
the dirty data can still be written back to memory later on.

To work around this, dma_inv_range() on these two processors is
implemented as dma_flush_range() (i.e. do a clean D-cache line before
doing the invalidate D-cache line.)  For this, we currently have a
processor ID check in xscale_dma_inv_range(), but a better solution
is to add a separate cache_fns and proc_info for A0/A1 80200.
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Dan Williams

commit a6a38a66 changed the iop321 id to a value that does not work with all platforms.  Change the mask to permit bit 11.  Tested on an iq80321 600Mhz CRB.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Lennert Buytenhek

The IOP 80219 xscale CPU is a stripped down version of the IOP32x.
But the fact that the 80219 and IOP32x are very similar doesn't mean
that they need to share a cpu table entry.  It's also somewhat confusing
for the end user to see the 80219 reported as an IOP32x, so this patch
splits the IOP32x cpu table entry to make a separate entry for the
80219.
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Nicolas Pitre

According to the Intel PXA27x Processor Family Specification
Update document (doc.nr. 280071-009) erratum E7, some care must be taken
to locate the disabling and re-enabling of the MMU to the beginning of a
cache line to avoid problems in some circumstances.

Credits to Simon Vogl <simon.vogl@researchstudios.at> for bringing this
up.
Signed-off-by: NNicolas Pitre <nico@cam.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

On some CPUs, bit 4 of section mappings means "update the
cache when written to".  On others, this bit is required to
be one, and others it's required to be zero.  Finally, on
ARMv6 and above, setting it turns on "no execute" and prevents
speculative prefetches.

With all these combinations, no one value fits all CPUs, so we
have to pick a value depending on the CPU type, and the area
we're mapping.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Most MMU-based CPUs have a restriction on the setting of the data cache
enable and mmu enable bits in the control register, whereby if the data
cache is enabled, the MMU must also be enabled.  Enabling the data
cache without the MMU is an invalid combination.

However, there are CPUs where the data cache can be enabled without the
MMU.

In order to allow these CPUs to take advantage of that, provide a
method whereby each proc-*.S file defines the control regsiter value
for use with nommu (with the MMU disabled.)  Later on, when we add
support for enabling the MMU on these devices, we can adjust the
"crval" macro to also enable the data cache for nommu.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>