Let's suppose a highmem page is kmap'd with kmap(). A pkmap entry is
used, the page mapped to it, and the virtual cache is dirtied. Then
kunmap() is used which does virtually nothing except for decrementing a
usage count.
Then, let's suppose the _same_ page gets mapped using kmap_atomic().
It is therefore mapped onto a fixmap entry instead, which has a
different virtual address unaware of the dirty cache data for that page
sitting in the pkmap mapping.
Fortunately it is easy to know if a pkmap mapping still exists for that
page and use it directly with kmap_atomic(), thanks to kmap_high_get().
And actual testing with a printk in the added code path shows that this
condition is actually met *extremely* frequently. Seems that we've been
quite lucky that things have worked so well with highmem so far.
Cc: stable@kernel.org
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In xdr_partial_copy_from_skb() there is that sequence:
kaddr = kmap_atomic(*ppage, KM_SKB_SUNRPC_DATA);
[...]
flush_dcache_page(*ppage);
kunmap_atomic(kaddr, KM_SKB_SUNRPC_DATA);
Mixing flush_dcache_page() and kmap_atomic() is a bit odd,
especially since kunmap_atomic() must deal with cache issues
already. OTOH the non-highmem case must use flush_dcache_page()
as kunmap_atomic() becomes a no op with no cache maintenance.
Problem is that with highmem the implementation of kmap_atomic()
doesn't set page->virtual, and page_address(page) returns 0 in
that case. Here flush_dcache_page() calls __flush_dcache_page()
which calls __cpuc_flush_dcache_page(page_address(page)) resulting
in a kernel oops.
None of the kmap_atomic() implementations uses set_page_address().
Hence we can assume page_address() is always expected to return 0 in
that case. Let's conditionally call __cpuc_flush_dcache_page() only
when the page address is non zero, and perform that test only when
highmem is configured.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Currently, highmem is selectable, and you can request an increased
vmalloc area. However, none of this has any effect on the memory
layout since a patch in the highmem series was accidentally dropped.
Moreover, even if you did want highmem, all memory would still be
registered as lowmem, possibly resulting in overflow of the available
virtual mapping space.
The highmem boundary is determined by the highest allowed beginning
of the vmalloc area, which depends on its configurable minimum size
(see commit 60296c71f6 for details on
this).
We should create mappings and initialize bootmem only for low memory,
while the zone allocator must still be told about highmem.
Currently, memory nodes which are completely located in high memory
are not supported. This is not a huge limitation since systems
relying on highmem support are unlikely to have discontiguous memory
with large holes.
[ A similar patch was meant to be merged before commit 5f0fbf9eca
and be available in Linux v2.6.30, however some git rebase screw-up
of mine dropped the first commit of the series, and that goofage
escaped testing somehow as well. -- Nico ]
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Nicolas Pitre <nico@marvell.com>
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>
* '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
...
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>
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>
* '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
...
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>
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>
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>
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>
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>
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>
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>
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>
* 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
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
"""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>
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>
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>
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>
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>
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>
This is the minimum fixmap interface expected to be implemented by
architectures supporting highmem.
We have a second level page table already allocated and covering
0xfff00000-0xffffffff because the exception vector page is located
at 0xffff0000, and various cache tricks already use some entries above
0xffff0000. Therefore the PTEs covering 0xfff00000-0xfffeffff are free
to be used.
However the XScale cache flushing code already uses virtual addresses
between 0xfffe0000 and 0xfffeffff.
So this reserves the 0xfff00000-0xfffdffff range for fixmap stuff.
The Documentation/arm/memory.txt information is updated accordingly,
including the information about the actual top of DMA memory mapping
region which didn't match the code.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
