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>

asm code really wants asm/hwcap.h, so include that instead.
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>

Feroceon L2 cache can work in eighther write through or write back mode
on Kirkwood. Add the option to configure this mode according to Kconfig.
Signed-off-by: NRonen Shitrit <rshitrit@marvell.com>
Signed-off-by: NNicolas Pitre <nico@marvell.com>

On Feroceon platforms that have a branch prediction unit, bit 11 of the
cp15 control register controls the BPU.  This patch keeps the old value
of this bit instead of always clearing it.
Signed-off-by: NSaeed Bishara <saeed@marvell.com>
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Signed-off-by: NNicolas Pitre <nico@marvell.com>

Add support for the Feroceon 88fr571-vd CPU core as found in e.g.
the Marvell Discovery Duo family of ARM SoCs.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>

Add support for the Shiva 88fr131 CPU core as found in e.g. the
Marvell Kirkwood family of ARM SoCs.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>

This patch adds support for the unified Feroceon L2 cache controller
as found in e.g. the Marvell Kirkwood and Marvell Discovery Duo
families of ARM SoCs.

Note that:

- Page table walks are outer uncacheable on Kirkwood and Discovery
  Duo, since the ARMv5 spec provides no way to indicate outer
  cacheability of page table walks (specifying it in TTBR[4:3] is
  an ARMv6+ feature).

  This requires adding L2 cache clean instructions to
  proc-feroceon.S (dcache_clean_area(), set_pte()) as well as to
  tlbflush.h ({flush,clean}_pmd_entry()).  The latter case is handled
  by defining a new TLB type (TLB_FEROCEON) which is almost identical
  to the v4wbi one but provides a TLB_L2CLEAN_FR flag.

- The Feroceon L2 cache controller supports L2 range (i.e. 'clean L2
  range by MVA' and 'invalidate L2 range by MVA') operations, and this
  patch uses those range operations for all Linux outer cache
  operations, as they are faster than the regular per-line operations.

  L2 range operations are not interruptible on this hardware, which
  avoids potential livelock issues, but can be bad for interrupt
  latency, so there is a compile-time tunable (MAX_RANGE_SIZE) which
  allows you to select the maximum range size to operate on at once.
  (Valid range is between one cache line and one 4KiB page, and must
  be a multiple of the line size.)
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>

This patch adds support for the L1 D cache range operations that
are supported by the Marvell Discovery Duo and Marvell Kirkwood
ARM SoCs.
Signed-off-by: NStanislav Samsonov <samsonov@marvell.com>
Acked-by: NSaeed Bishara <saeed@marvell.com>
Reviewed-by: NNicolas Pitre <nico@marvell.com>
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>

There are a couple more Feroceon-based SoCs out in the field that use
different Variant and Architecture fields in their Main ID registers
-- this patch tweaks the processor match/mask in proc-feroceon.S to
catch those SoCs as well.
Signed-off-by: NKe Wei <kewei@marvell.com>
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>

Flushing the L1 D cache with a test/clean/invalidate loop is very
easy in software, but it is not the quickest way of doing it, as
there is a lot of overhead involved in re-scanning the cache from
the beginning every time we hit a dirty line.

This patch makes proc-feroceon.S use "clean+invalidate by set/way"
loops according to possible cache configuration of Feroceon CPUs
(either direct-mapped or 4-way set associative).
Signed-off-by: NNicolas Pitre <nico@marvell.com>
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>

Annotate the entries for the 88fr531-vd CPU core in
arch/arm/boot/compressed/head.S and arch/arm/mm/proc-feroceon.S
with the full name of the core.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Acked-by: NRussell King <linux@arm.linux.org.uk>

More cosmetic cleanup:
- Replace 8-space indents by proper tab indents.
- In structure initialisers, use a trailing comma for every member.
- Collapse "},\n{" in structure initialiers to "}, {".
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Acked-by: NRussell King <linux@arm.linux.org.uk>

This patch implements a set of Feroceon-specific
{copy,clear}_user_page() routines that perform more optimally than
the generic implementations.  This also deals with write-allocate
caches (Feroceon can run L1 D in WA mode) which otherwise prevents
Linux from booting.

[nico: optimized the code even further]
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Tested-by: NSylver Bruneau <sylver.bruneau@googlemail.com>
Tested-by: NMartin Michlmayr <tbm@cyrius.com>
Signed-off-by: NNicolas Pitre <nico@marvell.com>

One overzealous .align 10 fixed, and a few .align5 added.
Signed-off-by: NNicolas Pitre <nico@marvell.com>

Since the Feroceon cache replacement policy is always pseudorandom
(and the relevant control register bit is ignored), remove the
CONFIG_CPU_CACHE_ROUND_ROBIN check from proc-feroceon.S.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Signed-off-by: NNicolas Pitre <nico@marvell.com>

Since the Feroceon doesn't have a global WT override bit like
ARM926 does, remove all code relating to this mode of operation
from proc-feroceon.S.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Signed-off-by: NNicolas Pitre <nico@marvell.com>

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>

This enables the usage of some old Feroceon cores
for which the CPU ID is equal to the ARM926 ID.
Relevant for Feroceon-1850 and old Feroceon-2850.
Signed-off-by: NTzachi Perelstein <tzachi@marvell.com>
Signed-off-by: NNicolas Pitre <nico@marvell.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The Feroceon is a family of independent ARMv5TE compliant CPU core
implementations, supporting a variable depth pipeline and out-of-order
execution.  The Feroceon is configurable with VFP support, and the
later models in the series are superscalar with up to two instructions
per clock cycle.

This patch adds the initial low-level cache/TLB handling for this core.
Signed-off-by: NAssaf Hoffman <hoffman@marvell.com>
Reviewed-by: NTzachi Perelstein <tzachi@marvell.com>
Reviewed-by: NNicolas Pitre <nico@marvell.com>
Reviewed-by: NLennert Buytenhek <buytenh@marvell.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Jon Eibertzon writes:
> We have noticed that the I-cache is disabled while waiting for
> interrupt in cpu_arm926_do_idle in arch/arm/mm/proc-arm926.S
> and we are curious to know why, because this causes us a great
> performance hit when executing in FIQ-handlers. Is it assumed
> here that every individual FIQ-handler re-enables the I-cache?

The I-cache disable is an errata workaround, so the solution is to
disable FIQs across the section with the I-cache disabled.
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>

Don't set HWCAP_VFP in the processor support file; not only does it
depend on the processor features, but it also depends on the support
code being present.  Therefore, only set it if the support code
detects that we have a VFP coprocessor attached.

Also, move the VFP handling of the coprocessor access register into
the VFP support code.
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>

Patch from Catalin Marinas

The ARM926EJ-S CPU has the VFP coprocessor and therefore it should be shown
in the /proc/cpuinfo if CONFIG_VFP is enabled.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

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>

The "id(wb)BRR" suffix reports which CPU debugging options were (or
were not) selected at kernel build time.  Rather than have every
proc-*.S file implement this, report the control register value,
from which this information can be deduced.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

In noMMU mode, various of functions which are defined in mm/proc-*.S
is not valid or needed to be avoided. i.g. switch_mm is not needed,
just returns and this makes the I & D caches are valid which shows
great improvement of performance including task switching and IPC.
Signed-off-by: NHyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

asm/hardware.h is not required for the majority of processor support
files, ioremap support, mm initialisation, acorn IO support, nor
the debug code (which picks up its machine specific includes via
debug-macros.S)
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move the hardware PMD and PTE page table definitions from pgtable.h
into pgtable-hwdef.h, and include pgtable-hwdef.h as necessary.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Ben Dooks

The `make buildcheck` is erroneously reporting that the .proc.info
list is referencing items in the .init section as it is not itself
postfixed with .init
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!