Commit graph

178 commits

Author SHA1 Message Date
Russell King 42578c82e0 Merge branch 'for-rmk' of git://linux-arm.org/linux-2.6 into devel
Conflicts:
	arch/arm/Kconfig
	arch/arm/kernel/smp.c
	arch/arm/mach-realview/Makefile
	arch/arm/mach-realview/platsmp.c
2009-06-11 15:35:00 +01:00
Russell King 547c32aeb5 Merge branch for-rmk-devel of git://aeryn.fluff.org.uk/bjdooks/linux into devel 2009-06-10 22:41:06 +01:00
Russell King 7698fdedcf Merge branch 'for-rmk' of git://git.marvell.com/orion into devel 2009-06-08 19:27:13 +01:00
Nicolas Pitre c1191b0e3b [ARM] Kirkwood: create a mapping for the Security Accelerator SRAM
Always creating the physical mapping should do no harm, so let's remove
the interface that was provided for its optional creation and make the
mapping static.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-06-08 13:05:02 -04:00
Russell King c7f7ff179c Merge branch 'smp' into devel 2009-06-01 18:35:26 +01:00
Catalin Marinas 26584853a4 Add core support for ARMv6/v7 big-endian
Starting with ARMv6, the CPUs support the BE-8 variant of big-endian
(byte-invariant). This patch adds the core support:

- setting of the BE-8 mode via the CPSR.E register for both kernel and
  user threads
- big-endian page table walking
- REV used to rotate instructions read from memory during fault
  processing as they are still little-endian format
- Kconfig and Makefile support for BE-8. The --be8 option must be passed
  to the final linking stage to convert the instructions to
  little-endian

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 14:00:18 +01:00
Catalin Marinas d71e1352e2 Clear the IT state when invoking a Thumb-2 signal handler
If a process is interrupted during an If-Then block and a signal is
invoked, the ITSTATE bits must be cleared otherwise the handler would
not run correctly.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joseph S. Myers <joseph@codesourcery.com>
2009-05-30 14:00:15 +01:00
Catalin Marinas faa7bc51c1 Check whether the TLB operations need broadcasting on SMP systems
ARMv7 SMP hardware can handle the TLB maintenance operations
broadcasting in hardware so that the software can avoid the costly IPIs.
This patch adds the necessary checks (the MMFR3 CPUID register) to avoid
the broadcasting if already supported by the hardware.

(this patch is based on the work done by Tony Thompson @ ARM)

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 14:00:14 +01:00
Colin Tuckley 1b504bbe7a RealView: Add support for the RealView/PBX platform
This is a RealView platform supporting core tiles with ARM11MPCore,
Cortex-A8 or Cortex-A9 (multicore) processors. It has support for MMC,
CompactFlash, PCI-E.

Signed-off-by: Colin Tuckley <colin.tuckley@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 13:56:12 +01:00
Linus Torvalds 78b170f45b Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] update mach-types
  [ARM] Add cmpxchg support for ARMv6+ systems (v5)
  [ARM] barriers: improve xchg, bitops and atomic SMP barriers
  Gemini: Fix SRAM/ROM location after memory swap
  MAINTAINER: Add F: entries for Gemini and FA526
  [ARM] disable NX support for OABI-supporting kernels
  [ARM] add coherent DMA mask for mv643xx_eth
  [ARM] pxa/palm: fix PalmLD/T5/TX AC97 MFP
  [ARM] pxa: add parameter to clksrc_read() for pxa168/910
  [ARM] pxa: fix the incorrectly defined drive strength macros for pxa{168,910}
  [ARM] Orion: Remove explicit name for platform device resources
  [ARM] Kirkwood: Correct MPP for SATA activity/presence LEDs of QNAP TS-119/TS-219.
  [ARM] pxa/ezx: fix pin configuration for low power mode
  [ARM] pxa/spitz: provide spitz_ohci_exit() that unregisters USB_HOST GPIO
  [ARM] pxa: enable GPIO receivers after configuring pins
  [ARM] pxa: allow gpio_reset drive high during normal work
  [ARM] pxa: save/restore PGSR on suspend/resume.
2009-05-29 16:07:39 -07:00
Oskar Schirmer c3dc5bec05 flat: fix data sections alignment
The flat loader uses an architecture's flat_stack_align() to align the
stack but assumes word-alignment is enough for the data sections.

However, on the Xtensa S6000 we have registers up to 128bit width
which can be used from userspace and therefor need userspace stack and
data-section alignment of at least this size.

This patch drops flat_stack_align() and uses the same alignment that
is required for slab caches, ARCH_SLAB_MINALIGN, or wordsize if it's
not defined by the architecture.

It also fixes m32r which was obviously kaput, aligning an
uninitialized stack entry instead of the stack pointer.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Oskar Schirmer <os@emlix.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <cooloney@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Johannes Weiner <jw@emlix.com>
Acked-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29 08:40:02 -07:00
Russell King 42f1d2e06a Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-davinci into devel 2009-05-29 10:04:24 +01:00
Mathieu Desnoyers ecd322c9b3 [ARM] Add cmpxchg support for ARMv6+ systems (v5)
Add cmpxchg/cmpxchg64 support for ARMv6K and ARMv7 systems
(original patch from Catalin Marinas <catalin.marinas@arm.com>)

The cmpxchg and cmpxchg64 functions can be implemented using the
LDREX*/STREX* instructions. Since operand lengths other than 32bit are
required, the full implementations are only available if the ARMv6K
extensions are present (for the LDREXB, LDREXH and LDREXD instructions).

For ARMv6, only 32-bits cmpxchg is available.

Mathieu :

Make cmpxchg_local always available with best implementation for all type sizes (1, 2, 4 bytes).
Make cmpxchg64_local always available.

Use "Ir" constraint for "old" operand, like atomic.h atomic_cmpxchg does.

Change since v3 :
- Add "memory" clobbers (thanks to Nicolas Pitre)
- removed __asmeq(), only needed for old compilers, very unlikely on ARMv6+.

Note : ARMv7-M should eventually be ifdefed-out of cmpxchg64. But it's not
supported by the Linux kernel currently.

Put back arm < v6 cmpxchg support.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-28 21:10:31 +01:00
Russell King bac4e960b5 [ARM] barriers: improve xchg, bitops and atomic SMP barriers
Mathieu Desnoyers pointed out that the ARM barriers were lacking:

- cmpxchg, xchg and atomic add return need memory barriers on
  architectures which can reorder the relative order in which memory
  read/writes can be seen between CPUs, which seems to include recent
  ARM architectures. Those barriers are currently missing on ARM.

- test_and_xxx_bit were missing SMP barriers.

So put these barriers in.  Provide separate atomic_add/atomic_sub
operations which do not require barriers.

Reported-Reviewed-and-Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-28 19:39:27 +01:00
Russell King e03cdade0c [ARM] smp: use new cpumask functions
Convert cpu_*_mask bit twiddling to the new set_cpu_*() API.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-28 14:16:52 +01:00
Russell King 56a459314a Merge branch 'iommu' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6.git into devel 2009-05-25 10:20:21 +01:00
Russell King fc05505b77 Merge branch 'ixp4xx' of git://git.kernel.org/pub/scm/linux/kernel/git/chris/linux-2.6 into devel 2009-05-23 23:18:40 +01:00
Hiroshi DOYU 69d3a84a64 omap iommu: simple virtual address space management
This patch provides a device drivers, which has a omap iommu, with
address mapping APIs between device virtual address(iommu), physical
address and MPU virtual address.

There are 4 possible patterns for iommu virtual address(iova/da) mapping.

    |iova/			  mapping		iommu_		page
    | da	pa	va	(d)-(p)-(v)		function	type
  ---------------------------------------------------------------------------
  1 | c		c	c	 1 - 1 - 1	  _kmap() / _kunmap()	s
  2 | c		c,a	c	 1 - 1 - 1	_kmalloc()/ _kfree()	s
  3 | c		d	c	 1 - n - 1	  _vmap() / _vunmap()	s
  4 | c		d,a	c	 1 - n - 1	_vmalloc()/ _vfree()	n*

    'iova':	device iommu virtual address
    'da':	alias of 'iova'
    'pa':	physical address
    'va':	mpu virtual address

    'c':	contiguous memory area
    'd':	dicontiguous memory area
    'a':	anonymous memory allocation
    '()':	optional feature

    'n':	a normal page(4KB) size is used.
    's':	multiple iommu superpage(16MB, 1MB, 64KB, 4KB) size is used.

    '*':	not yet, but feasible.

Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
2009-05-19 08:23:49 +03:00
Ben Dooks bcb8a0d6f5 [ARM] S3C: Merge next-s3c64xx-dma2 into for-rmk-devel
Merge branch 'next-s3c64xx-dma2' into for-rmk-devel

Conflicts:

	arch/arm/plat-s3c64xx/Makefile
2009-05-18 16:32:29 +01:00
Ben Dooks fa7a7883fe [ARM] S3C64XX: DMA support
Add support for the DMA blocks in the S3C64XX series of CPUS,
which are based on the ARM PL080 PrimeCell system.

Unfortunately, these DMA controllers diverge from the PL080
design by adding another DMA controller register and
configuration for OneNAND.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-05-18 16:29:21 +01:00
Russell King f32f4ce257 [ARM] smp: allow re-use of realview localtimer TWD support
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-17 19:16:41 +01:00
Russell King a8cbcd92bd [ARM] smp: separate SCU support code from realview
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-17 19:00:37 +01:00
Russell King 49613d4d9a [ARM] smp: SCU is used on non-realview platforms
The SCU can be used by non-realview platforms, so make it visible
for other people to use rather than having them copy the header file.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-17 18:59:57 +01:00
Russell King bc28248ee2 [ARM] smp: move core localtimer support out of platform specific files
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-17 18:58:34 +01:00
Russell King 826681043d [ARM] smp: fix cpumask usage in ARM SMP code
The ARM SMP code wasn't properly updated for the cpumask changes, which
results in smp_timer_broadcast() broadcasting ticks to non-online CPUs.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-17 16:22:46 +01:00
Paul Gortmaker ae51e60984 [ARM] 5507/1: support R_ARM_MOVW_ABS_NC and MOVT_ABS relocation types
From: Bruce Ashfield <bruce.ashfield@windriver.com>

To fully support the armv7-a instruction set/optimizations, support
for the R_ARM_MOVW_ABS_NC and R_ARM_MOVT_ABS relocation types is
required.

The MOVW and MOVT are both load-immediate instructions, MOVW loads 16
bits into the bottom half of a register, and MOVT loads 16 bits into the
top half of a register.

The relocation information for these instructions has a full 32 bit
value, plus an addend which is stored in the 16 immediate bits in the
instruction itself.  The immediate bits in the instruction are not
contiguous (the register # splits it into a 4 bit and 12 bit value),
so the addend has to be extracted accordingly and added to the value.
The value is then split and put into the instruction; a MOVW uses the
bottom 16 bits of the value, and a MOVT uses the top 16 bits.

Signed-off-by: David Borman <david.borman@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-07 17:21:01 +01:00
Ben Dooks c07f87f22e [ARM] VIC: Add power management device
Add power management support to the VIC by registering
each VIC as a system device to get suspend/resume
events going.

Since the VIC registeration is done early, we need to
record the VICs in a static array which is used to add
the system devices later once the initcalls are run. This
means there is now a configuration value for the number
of VICs in the system.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-05-07 11:04:57 +01:00
Russell King 924a158a12 [ARM] Convert pmd_page() to be highmem safe
In the long run, we may want to place page tables in highmem.  However,
pmd_page() has traditionally been coded to convert the physical address
to a virtual one, which won't work with highmem pages.  Instead,
translate the physical address to a PFN, and then convert the PFN to a
struct page instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-26 13:14:52 +01:00
Mikael Pettersson eb8f3142fa [ARM] 5456/1: add sys_preadv and sys_pwritev
Kernel 2.6.30-rc1 added sys_preadv and sys_pwritev to most archs
but not ARM, resulting in

<stdin>:1421:2: warning: #warning syscall preadv not implemented
<stdin>:1425:2: warning: #warning syscall pwritev not implemented

This patch adds sys_preadv and sys_pwritev to ARM.

These syscalls simply take five long-sized parameters, so they
should have no calling-convention/ABI issues in the kernel.

Tested on armv5tel eabi using a preadv/pwritev test program posted
on linuxppc-dev earlier this month.

It would be nice to get this into the kernel before 2.6.30 final,
so that glibc's kernel version feature test for these syscalls
doesn't have to special-case ARM.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-20 14:01:39 +01:00
Aaro Koskinen 7fccfc00c0 [ARM] 5450/1: Flush only the needed range when unmapping a VMA
When unmapping N pages (e.g. shared memory) the amount of TLB flushes
done can be (N*PAGE_SIZE/ZAP_BLOCK_SIZE)*N although it should be N at
maximum. With PREEMPT kernel ZAP_BLOCK_SIZE is 8 pages, so there is a
noticeable performance penalty when unmapping a large VMA and the system
is spending its time in flush_tlb_range().

The problem is that tlb_end_vma() is always flushing the full VMA
range. The subrange that needs to be flushed can be calculated by
tlb_remove_tlb_entry(). This approach was suggested by Hugh Dickins,
and is also used by other arches.

The speed increase is roughly 3x for 8M mappings and for larger mappings
even more.

Signed-off-by: Aaro Koskinen <Aaro.Koskinen@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-15 10:01:02 +01:00
Linus Walleij 8bd239d2ef [ARM] 5447/1: Add SZ_32K
This adds a SZ_32K define to the available sizes. I need it for an
upcoming platform support.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-08 20:35:57 +01:00
Robin Holt f5f7eac41d Allow rwlocks to re-enable interrupts
Pass the original flags to rwlock arch-code, so that it can re-enable
interrupts if implemented for that architecture.

Initially, make __raw_read_lock_flags and __raw_write_lock_flags stubs
which just do the same thing as non-flags variants.

Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
Signed-off-by: Robin Holt <holt@sgi.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <linux-arch@vger.kernel.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:05:11 -07:00
Russell King 9759d22c83 Merge branch 'master' into devel
Conflicts:
	arch/arm/include/asm/elf.h
	arch/arm/kernel/module.c
2009-03-28 20:30:18 +00:00
Russell King ed40d0c472 Merge branch 'origin' into devel
Conflicts:
	sound/soc/pxa/pxa2xx-i2s.c
2009-03-28 20:29:51 +00:00
Linus Torvalds ba1eb95cf3 Merge branch 'header-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'header-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (50 commits)
  x86: headers cleanup - setup.h
  emu101k1.h: fix duplicate include of <linux/types.h>
  compiler-gcc4: conditionalize #error on __KERNEL__
  remove __KERNEL_STRICT_NAMES
  make netfilter use strict integer types
  make drm headers use strict integer types
  make MTD headers use strict integer types
  make most exported headers use strict integer types
  make exported headers use strict posix types
  unconditionally include asm/types.h from linux/types.h
  make linux/types.h as assembly safe
  Neither asm/types.h nor linux/types.h is required for arch/ia64/include/asm/fpu.h
  headers_check fix cleanup: linux/reiserfs_fs.h
  headers_check fix cleanup: linux/nubus.h
  headers_check fix cleanup: linux/coda_psdev.h
  headers_check fix: x86, setup.h
  headers_check fix: x86, prctl.h
  headers_check fix: linux/reinserfs_fs.h
  headers_check fix: linux/socket.h
  headers_check fix: linux/nubus.h
  ...

Manually fix trivial conflicts in:
	include/linux/netfilter/xt_limit.h
	include/linux/netfilter/xt_statistic.h
2009-03-26 16:11:41 -07:00
Russell King 542f869f18 Merge branch 'for-rmk' of git://gitorious.org/linux-gemini/mainline into devel
Conflicts:
	arch/arm/mm/Kconfig

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-26 23:10:11 +00:00
Paulius Zaleckas 28853ac8fe ARM: Add support for FA526 v2
Adds support for Faraday FA526 core. This core is used at least by:
Cortina Systems Gemini and Centroid family
Cavium Networks ECONA family
Grain Media GM8120
Pixelplus ImageARM
Prolific PL-1029
Faraday IP evaluation boards

v2:
- move TLB_BTB to separate patch
- update copyrights

Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
2009-03-25 13:10:01 +02:00
Dmitry Baryshkov 17a92a788e [ARM] 5431/1: scoop: completely drop old-style SCOOP GPIO accessors
Now, as all places that use Scoop GPIO have been converted to use
GPIO API, drop old-style accessors completely.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-25 10:13:57 +00:00
Paulius Zaleckas bba7d0b9ba ARM: tlbflush.h: introduce TLB_BTB flag
Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
2009-03-25 10:58:47 +02:00
Russell King fbf2b1f9cf Merge branch 'highmem' into devel 2009-03-24 22:47:45 +00:00
root 9a38e989b8 Merge branch 'devel' of git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa-linux-2.6 into devel 2009-03-24 22:04:25 +00:00
Eric Miao 49cbe78637 [ARM] pxa: add base support for Marvell's PXA168 processor line
"""The Marvell® PXA168 processor is the first in a family of application
processors targeted at mass market opportunities in computing and consumer
devices. It balances high computing and multimedia performance with low
power consumption to support extended battery life, and includes a wealth
of integrated peripherals to reduce overall BOM cost .... """

See http://www.marvell.com/featured/pxa168.jsp for more information.

  1. Marvell Mohawk core is a hybrid of xscale3 and its own ARM core,
     there are many enhancements like instructions for flushing the
     whole D-cache, and so on

  2. Clock reuses Russell's common clkdev, and added the basic support
     for UART1/2.

  3. Devices are a bit different from the 'mach-pxa' way, the platform
     devices are now dynamically allocated only when necessary (i.e.
     when pxa_register_device() is called). Description for each device
     are stored in an array of 'struct pxa_device_desc'. Now that:

     a. this array of device description is marked with __initdata and
        can be freed up system is fully up

     b. which means board code has to add all needed devices early in
        his initializing function

     c. platform specific data can now be marked as __initdata since
        they are allocated and copied by platform_device_add_data()

  4. only the basic UART1/2/3 are added, more devices will come later.

Signed-off-by: Jason Chagas <chagas@marvell.com>
Signed-off-by: Eric Miao <eric.miao@marvell.com>
2009-03-23 10:11:34 +08:00
Daniel Silverstone 4731f8b66d [ARM] 5428/1: Module relocation update for R_ARM_V4BX
It would seem when building kernel modules with modern binutils
(required by modern GCC) for ARM v4T targets (specifically observed
with the Samsung 24xx SoC which is an 920T) R_ARM_V4BX relocations
are emitted for function epilogues.

This manifests at module load time with an "unknown relocation: 40"
error message.

The following patch adds the R_ARM_V4BX relocation to the ARM kernel
module loader. The relocation operation is taken from that within the
binutils bfd library.

Signed-off-by: Simtec Linux Team <linux@simtec.co.uk>
Signed-off-by: Vincent Sanders <vince@simtec.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-21 11:22:33 +00:00
Russell King be093beb60 [ARM] pass reboot command line to arch_reset()
OMAP wishes to pass state to the boot loader upon reboot in order to
instruct it whether to wait for USB-based reflashing or not.  There is
already a facility to do this via the reboot() syscall, except we ignore
the string passed to machine_restart().

This patch fixes things to pass this string to arch_reset().  This means
that we keep the reboot mode limited to telling the kernel _how_ to
perform the reboot which should be independent of what we request the
boot loader to do.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-19 16:20:24 +00:00
Russell King 05d9881bc4 Merge branch 'for-russell' of git://git.kernel.org/pub/scm/linux/kernel/git/chris/linux-2.6 into devel 2009-03-17 23:51:52 +00:00
Krzysztof Hałasa 0a07232ff6 IXP4xx: workaround for PCI prefetch problems near 64 MB boundary.
Map unused registers at the end of DMA region at 64 MB to allow PCI masters
to cross the boundary when prefetching data from SDRAM.

Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2009-03-17 15:00:55 +01:00
Nicolas Pitre 1bb772679f [ARM] Feroceon: add highmem support to L2 cache handling code
The choice is between looping over the physical range and performing
single cache line operations, or to map highmem pages somewhere, as
cache range ops are possible only on virtual addresses.

Because L2 range ops are much faster, we go with the later by factoring
the physical-to-virtual address conversion and use a fixmap entry for it
in the HIGHMEM case.

Possible future optimizations to avoid the pte setup cost:

 - do the pte setup for highmem pages only

 - determine a threshold for doing a line-by-line processing on physical
   addresses when the range is small

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
Nicolas Pitre 58edb51572 [ARM] make page_to_dma() highmem aware
If a machine class has a custom __virt_to_bus() implementation then it
must provide a __arch_page_to_dma() implementation as well which is
_not_ based on page_address() to support highmem.

This patch fixes existing __arch_page_to_dma() and provide a default
implementation otherwise.  The default implementation for highmem is
based on __pfn_to_bus() which is defined only when no custom
__virt_to_bus() is provided by the machine class.

That leaves only ebsa110 and footbridge which cannot support highmem
until they provide their own __arch_page_to_dma() implementation.
But highmem support on those legacy platforms with limited memory is
certainly not a priority.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
Nicolas Pitre 43377453af [ARM] introduce dma_cache_maint_page()
This is a helper to be used by the DMA mapping API to handle cache
maintenance for memory identified by a page structure instead of a
virtual address.  Those pages may or may not be highmem pages, and
when they're highmem pages, they may or may not be virtually mapped.
When they're not mapped then there is no L1 cache to worry about. But
even in that case the L2 cache must be processed since unmapped highmem
pages can still be L2 cached.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
Nicolas Pitre d73cd42893 [ARM] kmap support
The kmap virtual area borrows a 2MB range at the top of the 16MB area
below PAGE_OFFSET currently reserved for kernel modules and/or the
XIP kernel.  This 2MB corresponds to the range covered by 2 consecutive
second-level page tables, or a single pmd entry as seen by the Linux
page table abstraction.  Because XIP kernels are unlikely to be seen
on systems needing highmem support, there shouldn't be any shortage of
VM space for modules (14 MB for modules is still way more than twice the
typical usage).

Because the virtual mapping of highmem pages can go away at any moment
after kunmap() is called on them, we need to bypass the delayed cache
flushing provided by flush_dcache_page() in that case.

The atomic kmap versions are based on fixmaps, and
__cpuc_flush_dcache_page() is used directly in that case.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:20 -04:00