Commit Graph

488 Commits

Author SHA1 Message Date
Catalin Marinas
bdaaaec397 nommu: Do not set PRRR and NMRR in proc-v7.S if !MMU
ARMv7-R profile CPUs do not have these registers.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:35:06 +01:00
Catalin Marinas
8b79d5f217 nommu: Add #ifdef CONFIG_MMU around the PTE sanity checks
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:35:04 +01:00
Catalin Marinas
b32f3afe3c nommu: Include asm/setup.h in arch/arm/mm/nommu.c
This is needed for the struct meminfo definition.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:35:03 +01:00
Catalin Marinas
ab6494f0c9 nommu: Add noMMU support to the DMA API
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:35:02 +01:00
Catalin Marinas
09529f7a1a nommu: Fix the fault processing for the MMU-less case
The patch adds the necessary ifdefs around functions that only make
sense when the MMU is enabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:34:55 +01:00
Catalin Marinas
347c8b70b1 Thumb-2: Implement the unified arch/arm/mm support
This patch adds the ARM/Thumb-2 unified support to the arch/arm/mm/*
files.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-07-24 12:32:56 +01:00
Russell King
ba9b42e4ff [ARM] export __cpu_flush_dcache_page
Now required for libsas:

  Kernel: arch/arm/boot/Image is ready
  Kernel: arch/arm/boot/zImage is ready
  Building modules, stage 2.
  MODPOST 1096 modules
ERROR: "xscale_flush_kern_dcache_page" [drivers/scsi/libsas/libsas.ko] undefined!

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-07-05 15:25:00 +01:00
Linus Torvalds
9e268beb92 Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (49 commits)
  [ARM] idle: clean up pm_idle calling, obey hlt_counter
  [ARM] S3C: Fix gpio-config off-by-one bug
  [ARM] S3C64XX: add to_irq() support for EINT() GPIO
  [ARM] S3C64XX: clock.c: fix typo in usb-host clock ctrlbit
  [ARM] S3C64XX: fix HCLK gate defines
  [ARM] Update mach-types
  [ARM] wire up rt_tgsigqueueinfo and perf_counter_open
  OMAP2 clock/powerdomain: off by 1 error in loop timeout comparisons
  OMAP3 SDRC: set FIXEDDELAY when disabling SDRC DLL
  OMAP3: Add support for DPLL3 divisor values higher than 2
  OMAP3 SRAM: convert SRAM code to use macros rather than magic numbers
  OMAP3 SRAM: add more comments on the SRAM code
  OMAP3 clock/SDRC: program SDRC_MR register during SDRC clock change
  OMAP3 clock: add a short delay when lowering CORE clk rate
  OMAP3 clock: initialize SDRC timings at kernel start
  OMAP3 clock: remove wait for DPLL3 M2 clock to stabilize
  [ARM] Add old Feroceon support to compressed/head.S
  [ARM] 5559/1: Limit the stack unwinding caused by a kthread exit
  [ARM] 5558/1: Add extra checks to ARM unwinder to avoid tracing corrupt stacks
  [ARM] 5557/1: Discard some ARM.ex*.*exit.text sections when !HOTPLUG or !HOTPLUG_CPU
  ...
2009-06-22 14:56:13 -07:00
Linus Torvalds
d06063cc22 Move FAULT_FLAG_xyz into handle_mm_fault() callers
This allows the callers to now pass down the full set of FAULT_FLAG_xyz
flags to handle_mm_fault().  All callers have been (mechanically)
converted to the new calling convention, there's almost certainly room
for architectures to clean up their code and then add FAULT_FLAG_RETRY
when that support is added.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-21 13:08:22 -07:00
George G. Davis
c2860d43f5 [ARM] 5540/1: 32-bit Thumb-2 {ld,st}{m,rd} alignment fault fixup support
From: Min Zhang <mzhang@mvista.com>

Add alignment fault fixup support for 32-bit Thumb-2 LDM, LDRD, POP,
PUSH, STM and STRD instructions.  Alignment fault fixup support for
the remaining 32-bit Thumb-2 load/store instruction cases is not
included since ARMv6 and later processors include hardware support
for loads and stores of unaligned words and halfwords.

Signed-off-by: Min Zhang <mzhang@mvista.com>
Signed-off-by: George G. Davis <gdavis@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-06-19 16:35:34 +01:00
Russell King
187f81b3d8 Merge branch 'for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa-linux-2.6 into devel 2009-06-18 23:09:52 +01:00
Tomas 'Sleep_Walker' Cech
e6c3f4b89b [ARM] pxa/treo680: initial support
Signed-off-by: Tomáš Čech <sleep_walker@suse.cz>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Eric Miao <eric.miao@marvell.com>
2009-06-16 21:03:34 +08:00
Linus Torvalds
2cf4d4514d Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (417 commits)
  MAINTAINERS: EB110ATX is not ebsa110
  MAINTAINERS: update Eric Miao's email address and status
  fb: add support of LCD display controller on pxa168/910 (base layer)
  [ARM] 5552/1: ep93xx get_uart_rate(): use EP93XX_SYSCON_PWRCNT and EP93XX_SYSCON_PWRCN
  [ARM] pxa/sharpsl_pm: zaurus needs generic pxa suspend/resume routines
  [ARM] 5544/1: Trust PrimeCell resource sizes
  [ARM] pxa/sharpsl_pm: cleanup of gpio-related code.
  [ARM] pxa/sharpsl_pm: drop set_irq_type calls
  [ARM] pxa/sharpsl_pm: merge pxa-specific code into generic one
  [ARM] pxa/sharpsl_pm: merge the two sharpsl_pm.c since it's now pxa specific
  [ARM] sa1100: remove unused collie_pm.c
  [ARM] pxa: fix the conflicting non-static declarations of global_gpios[]
  [ARM] 5550/1: Add default configure file for w90p910 platform
  [ARM] 5549/1: Add clock api for w90p910 platform.
  [ARM] 5548/1: Add gpio api for w90p910 platform
  [ARM] 5551/1: Add multi-function pin api for w90p910 platform.
  [ARM] Make ARM_VIC_NR depend on ARM_VIC
  [ARM] 5546/1: ARM PL022 SSP/SPI driver v3
  ARM: OMAP4: SMP: Update defconfig for OMAP4430
  ARM: OMAP4: SMP: Enable SMP support for OMAP4430
  ...
2009-06-14 13:42:43 -07:00
Russell King
b7c11ec9f1 Merge branch 'u300' into devel
Conflicts:
	arch/arm/Makefile
Updates:
	arch/arm/mach-u300/core.c
	arch/arm/mach-u300/timer.c
2009-06-14 11:01:44 +01:00
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
1946d6ef9d [ARM] ARMv7 errata: only apply fixes when running on applicable CPU
Currently, whenever an erratum workaround is enabled, it will be
applied whether or not the erratum is relevent for the CPU.  This
patch changes this - we check the variant and revision fields in the
main ID register to determine which errata to apply.

We also avoid re-applying erratum 460075 if it has already been applied.
Applying this fix in non-secure mode results in the kernel failing to
boot (or even do anything.)

This fixes booting on some ARMv7 based platforms which otherwise
silently fail.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-06-02 22:36:20 +01:00
Russell King
a22f277bba [ARM] Kconfig: remove 'default n'
Kconfig entries default to n, so there's no need for this to be
explicitly specified.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-31 15:12:25 +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
23d1c515d8 ARMv7: Document the PRRR and NMRR registers setting
This patch adds a comment to the proc-v7.S file for the setting of the
PRRR and NMRR registers. It also sets the PRRR[13:12] bits to 0
(corresponding to the reserved TEX[0]CB encoding 110) to be consistent
with the documentation.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 14:00:16 +01:00
Catalin Marinas
213fb2a8ee ARMv7: Enable the SWP instruction
The SWP instruction has been deprecated starting with the ARMv6
architecture. On ARMv7 processors with the multiprocessor extensions
(like Cortex-A9), this instruction is disabled by default but it can be
enabled by setting bit 10 in the System Control register. Note that
setting this bit is safe even if the ARMv7 processor has the SWP
instruction enabled by default.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 14:00:16 +01:00
Tony Thompson
ba3c02636a ARMv7: Mark the PTWs inner WBWA on SMP and WB on UP
There are additional bits to set for the ARMv7 SMP extensions in the
TTBR registers. The IRGN bits order is counter-intuitive but it allows
software built for the ARMv7 base architecture to run on an
implementation with the MP extensions.

Signed-off-by: Tony Thompson <Anthony.Thompson@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.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
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
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
Linus Torvalds
2142babac9 Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm: (45 commits)
  [ARM] 5489/1: ARM errata: Data written to the L2 cache can be overwritten with stale data
  [ARM] 5490/1: ARM errata: Processor deadlock when a false hazard is created
  [ARM] 5487/1: ARM errata: Stale prediction on replaced interworking branch
  [ARM] 5488/1: ARM errata: Invalidation of the Instruction Cache operation can fail
  davinci: DM644x: NAND: update partitioning
  davinci: update DM644x support in preparation for more SoCs
  davinci: DM644x: rename board file
  davinci: update pin-multiplexing support
  davinci: serial: generalize for more SoCs
  davinci: DM355 IRQ Definitions
  davinci: DM646x: add interrupt number and priorities
  davinci: PSC: Clear bits in MDCTL reg before setting new bits
  davinci: gpio bugfixes
  davinci: add EDMA driver
  davinci: timers: use clk_get_rate()
  [ARM] pxa/littleton: add missing da9034 touchscreen support
  [ARM] pxa/zylonite: configure GPIO18/19 correctly, used by 2 GPIO expanders
  [ARM] pxa/zylonite: fix the issue of unused SDATA_IN_1 pin get AC97 not working
  [ARM] pxa: make ads7846 on corgi and spitz to sync on HSYNC
  [ARM] pxa: remove unused CPU_FREQ_PXA Kconfig symbol
  ...
2009-05-02 16:40:20 -07:00
Catalin Marinas
0516e4643c [ARM] 5489/1: ARM errata: Data written to the L2 cache can be overwritten with stale data
This patch is a workaround for the 460075 Cortex-A8 (r2p0) erratum. It
configures the L2 cache auxiliary control register so that the Write
Allocate mode for the L2 cache is disabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-30 20:13:00 +01:00
Catalin Marinas
855c551f5b [ARM] 5490/1: ARM errata: Processor deadlock when a false hazard is created
This patch adds a workaround for the 458693 Cortex-A8 (r2p0)
erratum. It sets the corresponding bits in the auxiliary control
register so that the PLD instruction becomes a NOP.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-30 20:12:59 +01:00
Catalin Marinas
7ce236fcd6 [ARM] 5487/1: ARM errata: Stale prediction on replaced interworking branch
This patch adds the workaround for the 430973 Cortex-A8 (r1p0..r1p2)
erratum. The BTAC/BTB is now flushed at every context switch.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-30 20:12:50 +01:00
Catalin Marinas
9cba3ccc8f [ARM] 5488/1: ARM errata: Invalidation of the Instruction Cache operation can fail
This patch implements the recommended workaround for erratum 411920
(ARM1136, ARM1156, ARM1176).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-30 20:12:47 +01:00
Linus Walleij
d98aac7592 [ARM] 5480/1: U300-v5 integrate into the ARM architecture
This hooks the U300 support into Kbuild and makes a small hook
in mmu.c for supporting an odd memory alignment with shared memory
on these systems.

This is rebased to RMK:s GIT HEAD. This patch tries to add the
Kconfig option in alphabetic order by option text and the Makefile
entry after config symbol.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-28 22:44:29 +01:00
Tim Abbott
991da17ec0 arm: Use __INIT macro instead of .text.init.
arm is placing some code in the .text.init section, but it does not
reference that section in its linker scripts.

This change moves this code from the .text.init section to the
.init.text section, which is presumably where it belongs.

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-27 19:51:58 -07:00
Marek Vasut
81854f82c5 [ARM] pxa: Add support for suspend on PalmTX, T5 and LD
Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Eric Miao <eric.miao@marvell.com>
2009-04-04 10:26:34 +08:00
Catalin Marinas
fe68e68f6a [ARM] 5439/1: Do not clear bit 10 of DFSR during abort handling on ARMv6
Because of an ARM1136 erratum (326103), the current v6_early_abort
function needs to set the correct FSR[11] value which determines whether
the data abort was caused by a read or write. For legacy reasons (bit 10
not handled by software), bit 10 was also cleared masking out imprecise
aborts on ARMv6 CPUs. This patch removes the clearing of bit 10 of FSR.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-04-01 22:15:57 +01:00
Nicolas Pitre
f000328ac1 [ARM] Kirkwood: small L2 code cleanup
Strictly speaking, a MCR instruction does not produce any output.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-28 22:39:30 -04:00
Maxime Bizon
d75de08727 [ARM] Kirkwood: invalidate L2 cache before enabling it
I get random oopses on my Kirkwood board at startup when L2 cache is
enabled. FYI I'm using Marvell uboot version 3.4.16

Each boot produces the same oops, but anything that changes the kernel
size (even only changing initramfs) makes the oops different.

I noticed that nothing invalidates the L2 cache before enabling it,
doing so fixes my problem.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-28 22:39:30 -04:00
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
Mikael Pettersson
f0bba9f934 [ARM] 5435/1: fix compile warning in sanity_check_meminfo()
Compiling recent 2.6.29-rc kernels for ARM gives me the following warning:

arch/arm/mm/mmu.c: In function 'sanity_check_meminfo':
arch/arm/mm/mmu.c:697: warning: comparison between pointer and integer

This is because commit 3fd9825c42
"[ARM] 5402/1: fix a case of wrap-around in sanity_check_meminfo()"
in 2.6.29-rc5-git4 added a comparison of a pointer with PAGE_OFFSET,
which is an integer.

Fixed by casting PAGE_OFFSET to void *.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-28 20:21:20 +00:00
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
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
Russell King
7d83f8fca5 Merge branch 'master' of git://git.marvell.com/orion into devel
Conflicts:

	arch/arm/mach-mx1/devices.c
2009-03-19 23:10:40 +00:00
Nicolas Pitre
3f973e2216 [ARM] ignore high memory with VIPT aliasing caches
VIPT aliasing caches have issues of their own which are not yet handled.
Usage of discard_old_kernel_data() in copypage-v6.c is not highmem ready,
kmap/fixmap stuff doesn't take account of cache colouring, etc.
If/when those issues are handled then this could be reverted.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:22 -04:00
Nicolas Pitre
3902a15e78 [ARM] xsc3: add highmem support to L2 cache handling code
On xsc3, L2 cache ops are possible only on virtual addresses.  The code
is rearranged so to have a linear progression requiring the least amount
of pte setups in the highmem case.  To protect the virtual mapping so
created, interrupts must be disabled currently up to a page worth of
address range.

The interrupt disabling is done in a way to minimize the overhead within
the inner loop.  The alternative would consist in separate code for
the highmem and non highmem compilation which is less preferable.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00
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
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
3835f6cb64 [ARM] mem_init(): make highmem pages available for use
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