On the r2p0, r2p1 and r2p2 versions of the Cortex-A9, data corruption
can occur under very rare conditions due to a store buffer optimisation.
This workaround sets a bit in the diagnostic register of the Cortex-A9,
disabling the optimisation and preventing the problem from occurring.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There are very few legitimate use cases, if any, for directly accessing
system RAM through /dev/mem. So let's mimic what they do on x86 and
forbid it when CONFIG_STRICT_DEVMEM is turned on.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
This patch populates the L1 entries for MT_MEMORY and MT_MEMORY_NONCACHED
types so that at boot-up, we can map memories outside system memory
at page level granularity
Previously the mapping was limiting to section level, which creates
unnecessary additional mapping for which physical memory may not
present. On the newer ARM with speculation, this is dangerous and can
result in untraceable aborts.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When the policy for user space is to ignore misaligned accesses from user
space, the processor then performs a documented rotation on the accessed
data. This is the result of the access being trapped, and the kernel
disabling the alignment trap before returning to user space again.
In kernel space we always want misaligned accesses to be fixed up. This
is enforced by always re-enabling the alignment trap on every entry into
kernel space from user space. No such re-enabling is performed when an
exception occurs while already in kernel space as the alignment trap is
always supposed to be enabled in that case.
There is however a small race window when a misaligned access in user
space is trapped and the alignment trap disabled, but the CPU didn't
return to user space just yet. Any exception would be entered from kernel
space at that point and the kernel would then execute with the alignment
trap disabled.
Thanks to Maxime Bizon <mbizon@freebox.fr> for providing a test module
that made this issue reproducible.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARMv7 onwards requires that there are no aliases to the same physical
location using different memory types (i.e. Normal vs Strongly Ordered).
Access to SO mappings when the unaligned accesses are handled in
hardware is also Unpredictable (pgprot_noncached() mappings in user
space).
The /dev/mem driver requires uncached mappings with O_SYNC. The patch
implements the phys_mem_access_prot() function which generates Strongly
Ordered memory attributes if !pfn_valid() (independent of O_SYNC) and
Normal Noncacheable (writecombine) if O_SYNC.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARMv7 processors like Cortex-A9 broadcast the cache maintenance
operations in hardware. This patch allows the
flush_dcache_page/update_mmu_cache pair to work in lazy flushing mode
similar to the UP case.
Note that cache flushing on SMP systems now takes place via the
set_pte_at() call (__sync_icache_dcache) and there is no race with other
CPUs executing code from the new PTE before the cache flushing took
place.
Tested-by: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On SMP systems, there is a small chance of a PTE becoming visible to a
different CPU before the current cache maintenance operations in
update_mmu_cache(). To avoid this, cache maintenance must be handled in
set_pte_at() (similar to IA-64 and PowerPC).
This patch provides a unified VIPT cache handling mechanism and
implements the __sync_icache_dcache() function for ARMv6 onwards
architectures. It is called from set_pte_at() and replaces the
update_mmu_cache(). The latter is still used on VIVT hardware where a
vm_area_struct is required.
Tested-by: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There are places in Linux where writes to newly allocated page cache
pages happen without a subsequent call to flush_dcache_page() (several
PIO drivers including USB HCD). This patch changes the meaning of
PG_arch_1 to be PG_dcache_clean and always flush the D-cache for a newly
mapped page in update_mmu_cache().
The patch also sets the PG_arch_1 bit in the DMA cache maintenance
function to avoid additional cache flushing in update_mmu_cache().
Tested-by: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit d73cd42 forced non-lazy cache flushing of highmem pages in
flush_dcache_page(). This isn't needed since __flush_dcache_page()
(called lazily from update_mmu_cache) can handle highmem pages (fixed by
commit 7e5a69e).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Setting of these bits can cause issues on other SMP SoC's not produced
by ARM.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On the r2p0, r2p1 and r2p2 versions of the Cortex-A9, data corruption
can occur if a shared cache line is replaced on one CPU as another CPU
is accessing it.
This workaround sets two bits in the diagnostic register of the Cortex-A9,
reducing the linefill issuing capabilities of the processor and
avoiding the erroneous behaviour.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On versions of the Cortex-A9 up to and including r2p2, under rare
circumstances, a DMB instruction between 2 write operations may not
ensure the correct visibility ordering of the 2 writes.
This workaround sets a bit in the diagnostic register of the Cortex-A9,
causing the DMB instruction to behave like a DSB, which functions
correctly on the affected cores.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Kconfig doesn't have any knowledge of specific v7 cores, so it is possible
to select errata workarounds that may cause inadvertent behaviour when
executed on a core other than those targetted by the fix.
This patch improves the variant and revision checking in proc-v7.S so
that the primary part number is also considered when applying errata
workarounds.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Stephen Rothwell reported this build failure:
arch/arm/mm/init.c: In function 'arm_memory_present':
arch/arm/mm/init.c:260: warning: ISO C90 forbids mixed declarations and code
Caused by commit 719c1514f2 ("memblock/arm: Use new accessors")
which forgot a closing brace on a new for_each_memblock() in
arm_memory_present().
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Russell King <linux@arm.linux.org.uk>
LKML-Reference: <4C91C544.5050907@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Dave Hylands reports:
| We've observed a problem with dma_alloc_writecombine when the system
| is under heavy load (heavy bus traffic). We've managed to reduce the
| problem to the following snippet, which is run from a kthread in a
| continuous loop:
|
| void *virtAddr;
| dma_addr_t physAddr;
| unsigned int numBytes = 256;
|
| for (;;) {
| virtAddr = dma_alloc_writecombine(NULL,
| numBytes, &physAddr, GFP_KERNEL);
| if (virtAddr == NULL) {
| printk(KERN_ERR "Running out of memory\n");
| break;
| }
|
| /* access DMA memory allocated */
| tmp = virtAddr;
| *tmp = 0x77;
|
| /* free DMA memory */
| dma_free_writecombine(NULL,
| numBytes, virtAddr, physAddr);
|
| ...sleep here...
| }
|
| By itself, the code will run forever with no issues. However, as we
| increase our bus traffic (typically using DMA) then the *tmp = 0x77
| line will eventually cause a page fault. If we add a small delay (a
| few microseconds) before the *tmp = 0x77, then we don't see a page
| fault, even under heavy load.
A dsb() is required after modifying the PTE entries to ensure that they
will always be visible. Add this dsb().
Reported-by: Dave Hylands <dhylands@gmail.com>
Tested-by: Dave Hylands <dhylands@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On ARM processors with hardware breakpoint and watchpoint support,
triggering these events results in a debug exception. These manifest
as prefetch and data aborts respectively.
arch/arm/mm/fault.c already provides hook_fault_code for hooking
into data aborts dependent on the DFSR. This patch adds a new function,
hook_ifault_code for hooking into prefetch aborts in the same manner.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: S. Karthikeyan <informkarthik@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
CPU_32v6K is selected by CPU_V7 but it only depends on CPU_V6.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
kunmap_atomic() is currently at level -4 on Rusty's "Hard To Misuse"
list[1] ("Follow common convention and you'll get it wrong"), except in
some architectures when CONFIG_DEBUG_HIGHMEM is set[2][3].
kunmap() takes a pointer to a struct page; kunmap_atomic(), however, takes
takes a pointer to within the page itself. This seems to once in a while
trip people up (the convention they are following is the one from
kunmap()).
Make it much harder to misuse, by moving it to level 9 on Rusty's list[4]
("The compiler/linker won't let you get it wrong"). This is done by
refusing to build if the type of its first argument is a pointer to a
struct page.
The real kunmap_atomic() is renamed to kunmap_atomic_notypecheck()
(which is what you would call in case for some strange reason calling it
with a pointer to a struct page is not incorrect in your code).
The previous version of this patch was compile tested on x86-64.
[1] http://ozlabs.org/~rusty/index.cgi/tech/2008-04-01.html
[2] In these cases, it is at level 5, "Do it right or it will always
break at runtime."
[3] At least mips and powerpc look very similar, and sparc also seems to
share a common ancestor with both; there seems to be quite some
degree of copy-and-paste coding here. The include/asm/highmem.h file
for these three archs mention x86 CPUs at its top.
[4] http://ozlabs.org/~rusty/index.cgi/tech/2008-03-30.html
[5] As an aside, could someone tell me why mn10300 uses unsigned long as
the first parameter of kunmap_atomic() instead of void *?
Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Cc: Russell King <linux@arm.linux.org.uk> (arch/arm)
Cc: Ralf Baechle <ralf@linux-mips.org> (arch/mips)
Cc: David Howells <dhowells@redhat.com> (arch/frv, arch/mn10300)
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> (arch/mn10300)
Cc: Kyle McMartin <kyle@mcmartin.ca> (arch/parisc)
Cc: Helge Deller <deller@gmx.de> (arch/parisc)
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> (arch/parisc)
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> (arch/powerpc)
Cc: Paul Mackerras <paulus@samba.org> (arch/powerpc)
Cc: "David S. Miller" <davem@davemloft.net> (arch/sparc)
Cc: Thomas Gleixner <tglx@linutronix.de> (arch/x86)
Cc: Ingo Molnar <mingo@redhat.com> (arch/x86)
Cc: "H. Peter Anvin" <hpa@zytor.com> (arch/x86)
Cc: Arnd Bergmann <arnd@arndb.de> (include/asm-generic)
Cc: Rusty Russell <rusty@rustcorp.com.au> ("Hard To Misuse" list)
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
v2: Fixes from Mike Rapoport
- remove unused header files (mach/dma.h and mach/nand.h)
- remove tegra 1 references from Makefile.boot
v2: fixes from Russell King
- remove mach/io.h include from mach/iomap.h
- fix whitespace in Kconfig
v2: from Colin Cross
- fix invalid immediate in debug-macro.S
v3:
- allow selection of multiple boards
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Erik Gilling <konkers@android.com>
This patch adds the Kconfig and Makefile for the new S5PV310 SoC.
It also updates arch/arm Kconfig, Makefile and arch/arm/mm/Kconfig
to include support for the new S5PV310.
Signed-off-by: Changhwan Youn <chaos.youn@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The implementation is pretty much similar. There is a -small- added
overhead by having another function call and the address shift.
If that becomes a concern, I suppose we could actually have memblock
itself expose a memblock_pfn_valid() which then ARM can use directly
with an appropriate #define...
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (291 commits)
ARM: AMBA: Add pclk support to AMBA bus infrastructure
ARM: 6278/2: fix regression in RealView after the introduction of pclk
ARM: 6277/1: mach-shmobile: Allow users to select HZ, default to 128
ARM: 6276/1: mach-shmobile: remove duplicate NR_IRQS_LEGACY
ARM: 6246/1: mmci: support larger MMCIDATALENGTH register
ARM: 6245/1: mmci: enable hardware flow control on Ux500 variants
ARM: 6244/1: mmci: add variant data and default MCICLOCK support
ARM: 6243/1: mmci: pass power_mode to the translate_vdd callback
ARM: 6274/1: add global control registers definition header file for nuc900
mx2_camera: fix type of dma buffer virtual address pointer
mx2_camera: Add soc_camera support for i.MX25/i.MX27
arm/imx/gpio: add spinlock protection
ARM: Add support for the LPC32XX arch
ARM: LPC32XX: Arch config menu supoport and makefiles
ARM: LPC32XX: Phytec 3250 platform support
ARM: LPC32XX: Misc support functions
ARM: LPC32XX: Serial support code
ARM: LPC32XX: System suspend support
ARM: LPC32XX: GPIO, timer, and IRQ drivers
ARM: LPC32XX: Clock driver
...
smp_processor_id() must not be called from a preemptible context (this
is checked by CONFIG_DEBUG_PREEMPT). kmap_high_l1_vipt() was doing so.
This lead to a problem where the wrong per_cpu kmap_high_l1_vipt_depth
could be incremented, causing a BUG_ON(*depth <= 0); in
kunmap_high_l1_vipt().
The solution is to move the call to smp_processor_id() after the call
to preempt_disable().
Originally by: Andrew Howe <ahowe@nvidia.com>
Signed-off-by: Gary King <gking@nvidia.com>
Acked-by: Nicolas Pitre <nico.as.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch is in preparation for a subsequent patch which adds barriers
to the I/O accessors. Since the mandatory barriers may do an L2 cache
sync, this patch avoids a recursive call into l2x0_cache_sync() via the
write*() accessors and wmb() and a call into l2x0_cache_sync() with the
l2x0_lock held.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell 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: Russell King <rmk+kernel@arm.linux.org.uk>
Statuses 3 (0b00011) and 6 (0x00110) of DFSR are Access Flags faults on
ARMv6K and ARMv7. Let's patch fsr_info[] at runtime if we are on ARMv7
or later.
Unfortunately, we don't have runtime check for 'K' extension, so we
can't check for it.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On ARM one Linux PGD entry contains two hardware entries (see page
tables layout in pgtable.h). We normally guarantee that we always
fill both L1 entries. But create_mapping() doesn't follow the rule.
It can create inidividual L1 entries, so here we have to call
pmd_none() check in do_translation_fault() for the entry really
corresponded to address, not for the first of pair.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add one more parameter to hook_fault_code() to be able to set 'code'
field of struct fsr_info.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
POSIX specify to use signal SIGBUS with code BUS_ADRALN for invalid
address alignment.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The DMA coherent remap area is used to provide an uncached mapping
of memory for coherency with DMA engines. Currently, we look for
any free hole which our allocation will fit in with page alignment.
However, this can lead to fragmentation of the area, and allows small
allocations to cross L1 entry boundaries. This is undesirable as we
want to move towards allocating sections of memory.
Align allocations according to the size, limiting the alignment between
the page and section sizes.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We don't need our own implementation of this, use the generic
library implementation instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This changes the TCM handling so that a fixed area is reserved at
0xfffe0000-0xfffeffff for TCM. This areas is used by XScale but
XScale does not have TCM so the mechanisms are mutually exclusive.
This change is needed to make TCM detection more dynamic while
still being able to compile code into it, and is a must for the
unified ARM goals: the current TCM allocation at different places
in memory for each machine would be a nightmare if you want to
compile a single image for more than one machine with TCM so it
has to be nailed down in one place.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If TCM is in use, we should display it in the virtual memory
layout along with everything else.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The earlier TCM memory regions were mapped as MT_MEMORY_UNCACHED
which doesn't really work on platforms supporting the new v6
features like the NX bit. Add unique MT_MEMORY_[I|D]TCM types
instead.
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add a common early allocator function, in preparation for switching
over to LMB. When we do, this function will need to do a little more
than just allocating memory; we need it zero initialized too.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move the platform specific bootmem memory reservations out of
arch/arm/mm/mmu.c into their respective platform files.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Everything should now be using sparsemem rather than discontigmem, so
remove the code supporting discontigmem from ARM.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than storing the minimum size of the vmalloc area, store the
maximum permitted address of the vmalloc area instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The TLS register is only available on ARM1136 r1p0 and later.
Set HWCAP_TLS flags if hardware TLS is available and test for
it if CONFIG_CPU_32v6K is not set for V6.
Note that we set the TLS instruction in __kuser_get_tls
dynamically as suggested by Jamie Lokier <jamie@shareable.org>.
Also the __switch_to code is optimized out in most cases as
suggested by Nicolas Pitre <nico@fluxnic.net>.
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On i.MX35 the L2X0_AUX_CTRL register does not have sensible reset
default values. Allow them to be overwritten with the aux_val/aux_mask
arguments passed to l2x0_init().
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
RealView boards with certain revisions of the L210/L220 cache controller
may have issues (hardware deadlock) with the mandatory barriers (DSB
followed by an L2 cache sync) when ARM_DMA_MEM_BUFFERABLE is enabled.
The patch disables ARM_DMA_MEM_BUFFERABLE for these boards.
Tested-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit f4d6477f introduced a workaround for the lack of hardware
broadcasting of the cache maintenance operations on ARM11MPCore.
However, the workaround is only valid on CPUs that do not do speculative
loads into the D-cache.
This patch adds a Kconfig option with the corresponding help to make the
above clear. When the DMA_CACHE_RWFO option is disabled, the kernel
behaviour is that prior to the f4d6477f commit. This also allows ARMv6
UP processors with speculative loads to work correctly.
For other processors, a different workaround may be needed.
Cc: Ronen Shitrit <rshitrit@marvell.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
A recent patch for DMA cache maintenance on ARM11MPCore added a write
for ownership trick to the v6_dma_inv_range() function. Such operation
destroys data already present in the buffer. However, this function is
used with with dma_sync_single_for_device() which is supposed to
preserve the existing data transfered into the buffer. This patch adds a
combination of read/write for ownership to preserve the original data.
Reported-by: Ronen Shitrit <rshitrit@marvell.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This macro is not defined when !CONFIG_MMU so this patch moves the
CONSISTENT_* definitions to the CONFIG_MMU section.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARMv6 and above have a restriction whereby aliasing virtual:physical
mappings must not have differing memory type and sharability
attributes. Strictly, this covers the memory type (strongly ordered,
device, memory), cache attributes (uncached, write combine, write
through, write back read alloc, write back write alloc) and the
shared bit.
However, using ioremap() and its variants on system RAM results in
mappings which differ in these attributes from the main system RAM
mapping. Other architectures which similar restrictions approch this
problem in the same way - they do not permit ioremap on main system
RAM.
Make ARM behave in the same way, with a WARN_ON() such that users can
be traced and an alternative approach found.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The VM subsystem assumes that there are valid memmap entries to
the bank end aligned to MAX_ORDER_NR_PAGES. It will try and read
these page structs, and so we cannot free any memmap entries that
it may inspect.
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
When functions incoming parameters are not in input operands list gcc
4.5 does not load the parameters into registers before calling this
function but the inline assembly assumes valid addresses inside this
function. This breaks the code because r0 and r1 are invalid when
execution enters v4wb_copy_user_page ()
Also the constant needs to be used as third input operand so account
for that as well.
Tested on qemu arm.
CC: <stable@kernel.org>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Instruction faults on pre-ARMv6 CPUs are interpreted as
a 'translation fault', but do_translation_fault doesn't
handle well if user mode trying to run instruction above
TASK_SIZE, and result in the infinite retry of that
instruction.
CC: <stable@kernel.org>
Signed-off-by: Anfei Zhou <anfei.zhou@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When CONFIG_DEBUG_HIGHMEM is used, the fixmap entry used for a highmem page
by kmap_atomic() is always cleared by kunmap_atomic(). This helps find
bad usages such as dereferences after the unmap, or overflow into the
adjacent fixmap areas.
But this debugging aid is completely bypassed when a kmap for the same
page already exists as the kmap is reused instead. ON VIVT systems we
have no choice but to reuse that kmap due to cache coherency issues,
but on non VIVT systems we should always force the fixmap usage when
debugging is active.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This fixes a bug in mm/init.c when freeing the TCM compile memory,
this was being referred to as a char * which is incorrect: this
will dereference the pointer and feed in the value at the location
instead of the address to it. Change it to a plain char and use
&(char) to reference it.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Cc: <stable@kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes the flush_cache_all for ARMv7 SMP.It was
missing from commit b8349b569a
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (224 commits)
ARM: remove 'select GENERIC_TIME'
ARM: 6136/1: ARCH_REQUIRE_GPIOLIB selects GENERIC_GPIO
ARM: 6074/1: oprofile: convert from sysdev to platform device
ARM: 6073/1: oprofile: remove old files and update KConfig
ARM: 6072/1: oprofile: use perf-events framework as backend
ARM: 6071/1: perf-events: allow modules to query the number of hardware counters
ARM: 6070/1: perf-events: add support for xscale PMUs
ARM: 6069/1: perf-events: use numeric ID to identify PMU
ARM: 6064/1: pmu: register IRQs at runtime
ARM: Optionally allow ARMv6 to use 'normal, bufferable' memory for DMA
ARM: 6134/1: Handle instruction cache maintenance fault properly
ARM: nwfpe: allow debugging output to be configured at runtime
ARM: rename mach_cpu_disable() to platform_cpu_disable()
ARM: 6132/1: PL330: Add common core driver
ARM: 6094/1: Extend cache-l2x0 to support the 16-way PL310
ARM: Move memory mapping into mmu.c
ARM: Ensure meminfo is sorted prior to sanity_check_meminfo
ARM: Remove useless linux/bootmem.h includes
ARM: convert /proc/cpu/aligment to seq_file
arm: use asm-generic/scatterlist.h
...
Provide a configuration option to allow the ARMv6 to use normal
bufferable memory for coherent DMA. This option is forced to 'y'
for ARMv7, and offered as a configuration option on ARMv6.
Enabling this option requires drivers to have the necessary barriers
to ensure that data in DMA coherent memory is visible prior to the
DMA operation commencing.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Between "clean D line..." and "invalidate I line" operations in
v7_coherent_user_range(), the memory page may get swapped out.
And the fault on "invalidate I line" could not be properly handled
causing the oops.
In ARMv6 "external abort on linefetch" replaced by "instruction cache
maintenance fault". Let's handle it as translation fault. It fixes the
issue.
I'm not sure if it's reasonable to check arch version in run-time.
Let's do it in compile time for now.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Siarhei Siamashka <siarhei.siamashka@nokia.com>
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The L310 cache controller's interface is almost identical
to the L210. One major difference is that the PL310 can
have up to 16 ways.
This change uses the cache's part ID and the Associativity
bits in the AUX_CTRL register to determine the number of ways.
Also, this version prints out the CACHE_ID and AUX_CTRL registers.
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Jason S. McMullan <jason.mcmullan@netronome.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert code away from ->read_proc/->write_proc interfaces. Switch to
proc_create()/proc_create_data() which makes addition of proc entries
reliable wrt NULL ->proc_fops, NULL ->data and so on.
Problem with ->read_proc et al is described here commit
786d7e1612 "Fix rmmod/read/write races in
/proc entries"
This patch is part of an effort to remove the old simple procfs PAGE_SIZE
buffer interface.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Enable Tauros2 L2 in mmp2. Tauros2 L2 is shared in Marvell ARM cores.
Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
The standard I-cache Invalidate All (ICIALLU) and Branch Predication
Invalidate All (BPIALL) operations are not automatically broadcast to
the other CPUs in an ARMv7 MP system. The patch adds the Inner Shareable
variants, ICIALLUIS and BPIALLIS, if ARMv7 and SMP.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The Snoop Control Unit on the ARM11MPCore hardware does not detect the
cache operations and the dma_cache_maint*() functions may leave stale
cache entries on other CPUs. The solution implemented in this patch
performs a Read or Write For Ownership in the ARMv6 DMA cache
maintenance functions. These LDR/STR instructions change the cache line
state to shared or exclusive so that the cache maintenance operation has
the desired effect.
Tested-by: George G. Davis <gdavis@mvista.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 7959722 introduced calls to copy_(to|from)_user_page() from
access_process_vm() in mm/nommu.c. The copy_to_user_page() was not
implemented on noMMU ARM.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 31aa8fd6 introduced the __arm_ioremap_caller() function but the
nommu.c version did not have the _caller suffix.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The show_mem() and mem_init() function are assuming that the page map is
contiguous and calculates the start and end page of a bank using (map +
pfn). This fails with SPARSEMEM where pfn_to_page() must be used.
Tested-by: Will Deacon <Will.Deacon@arm.com>
Tested-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Handle incorrectly reported permission faults for qsd8650. On
permission faults, retry MVA to PA conversion. If retry detects
translation fault. Report as translation fault.
Cc: Jamie Lokier <jamie@shareable.org>
Signed-off-by: Dave Estes <cestes@quicinc.com>
Fix compiler error in copypage-fs.c
missing struct vm_area_struct *vma in function
fa_copy_user_highpage
Signed-off-by: Hans Ulli Kroll <ulli.kroll@googlemail.com>
/tmp/ccJ3ssZW.s: Assembler messages:
/tmp/ccJ3ssZW.s:1952: Error: can't resolve `.text' {.text section} - `.LFB1077'
This is caused because:
.section .data
.section .text
.section .text
.previous
does not return us to the .text section, but the .data section; this
makes use of .previous dangerous if the ordering of previous sections
is not known.
Fix up the other users of .previous; .pushsection and .popsection are
a safer pairing to use than .section and .previous.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This enables the l2x0 support and ensures that the secondary
CPU can see the page table and secondary data at this point.
Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This cache flush occurs when we first insert a page into the page
tables, where a page did not exist previously. There can be no
cache lines associated with this virtual mapping, so this cache
flush is redundant.
Tested-by: Mike Rapoport <mike@compulab.co.il>
Tested-by: Mikael Pettersson <mikpe at it.uu.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When crash happens in interrupt context there is no userspace context.
We always use current->active_mm in those cases.
Signed-off-by: Mika Westerberg <ext-mika.1.westerberg@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The VIVT cache of a highmem page is always flushed before the page
is unmapped. This cache flush is explicit through flush_cache_kmaps()
in flush_all_zero_pkmaps(), or through __cpuc_flush_dcache_area() in
kunmap_atomic(). There is also an implicit flush of those highmem pages
that were part of a process that just terminated making those pages free
as the whole VIVT cache has to be flushed on every task switch. Hence
unmapped highmem pages need no cache maintenance in that case.
However unmapped pages may still be cached with a VIPT cache because the
cache is tagged with physical addresses. There is no need for a whole
cache flush during task switching for that reason, and despite the
explicit cache flushes in flush_all_zero_pkmaps() and kunmap_atomic(),
some highmem pages that were mapped in user space end up still cached
even when they become unmapped.
So, we do have to perform cache maintenance on those unmapped highmem
pages in the context of DMA when using a VIPT cache. Unfortunately,
it is not possible to perform that cache maintenance using physical
addresses as all the L1 cache maintenance coprocessor functions accept
virtual addresses only. Therefore we have no choice but to set up a
temporary virtual mapping for that purpose.
And of course the explicit cache flushing when unmapping a highmem page
on a system with a VIPT cache now can go, which should increase
performance.
While at it, because the code in __flush_dcache_page() has to be modified
anyway, let's also make sure the mapped highmem pages are pinned with
kmap_high_get() for the duration of the cache maintenance operation.
Because kunmap() does unmap highmem pages lazily, it was reported by
Gary King <GKing@nvidia.com> that those pages ended up being unmapped
during cache maintenance on SMP causing segmentation faults.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Write combining/cached device mappings are not setting the shared bit,
which could potentially cause problems on SMP systems since the cache
lines won't participate in the cache coherency protocol.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
