As per the dma_unmap_* calls, we don't touch the cache when a DMA
buffer transitions from device to CPU ownership. Presently, no
problems have been identified with speculative cache prefetching
which in itself is a new feature in later architectures. We may
have to revisit the DMA API later for these architectures anyway.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Validate the direction argument like x86 does. In addition,
validate the dma_unmap_* parameters against those passed to
dma_map_* when using the DMA bounce code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The dmabounce dma_sync_xxx() implementation have been broken for
quite some time; they all copy data between the DMA buffer and
the CPU visible buffer no irrespective of the change of ownership.
(IOW, a DMA_FROM_DEVICE mapping copies data from the DMA buffer
to the CPU buffer during a call to dma_sync_single_for_device().)
Fix it by getting rid of sync_single(), moving the contents into
the recently created dmabounce_sync_for_xxx() functions and adjusting
appropriately.
This also makes it possible to properly support the DMA range sync
functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Delete ARM's own cnt32_to_63.h as the copy in include/linux/ should now be
used instead.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can translate a struct page directly to a DMA address using
page_to_dma(). No need to use page_address() followed by
virt_to_dma().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than trying to (inaccurately) decode the cache type from the
registers each time we need to decide what type of cache we have,
use a bitmask initialized early during boot.
Since the setup is a one-off initialization, we can be a little more
clever and take account of the CPU architecture as well.
Note that we continue to achieve the compactness on optimised kernels
by forcing tests to always-false or always-true as appropriate, thereby
allowing the compiler to do build-time code elimination.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
PCI_DMA_BUS_IS_PHYS was defined to be zero, which meant we ignored
the DMA mask for IDE and SCSI transfers. This is wrong - we have
no DMA translation hardware. We want to obey DMA masks so that the
block layer performs bouncing itself.
Reported-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch provides an ARM implementation of ioremap_wc().
We use different page table attributes depending on which CPU we
are running on:
- Non-XScale ARMv5 and earlier systems: The ARMv5 ARM documents four
possible mapping types (CB=00/01/10/11). We can't use any of the
cached memory types (CB=10/11), since that breaks coherency with
peripheral devices. Both CB=00 and CB=01 are suitable for _wc, and
CB=01 (Uncached/Buffered) allows the hardware more freedom than
CB=00, so we'll use that.
(The ARMv5 ARM seems to suggest that CB=01 is allowed to delay stores
but isn't allowed to merge them, but there is no other mapping type
we can use that allows the hardware to delay and merge stores, so
we'll go with CB=01.)
- XScale v1/v2 (ARMv5): same as the ARMv5 case above, with the slight
difference that on these platforms, CB=01 actually _does_ allow
merging stores. (If you want noncoalescing bufferable behavior
on Xscale v1/v2, you need to use XCB=101.)
- Xscale v3 (ARMv5) and ARMv6+: on these systems, we use TEXCB=00100
mappings (Inner/Outer Uncacheable in xsc3 parlance, Uncached Normal
in ARMv6 parlance).
The ARMv6 ARM explicitly says that any accesses to Normal memory can
be merged, which makes Normal memory more suitable for _wc mappings
than Device or Strongly Ordered memory, as the latter two mapping
types are guaranteed to maintain transaction number, size and order.
We use the Uncached variety of Normal mappings for the same reason
that we can't use C=1 mappings on ARMv5.
The xsc3 Architecture Specification documents TEXCB=00100 as being
Uncacheable and allowing coalescing of writes, which is also just
what we need.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
pc_pointer() was a function to mask the PC for 26-bit ARMs, which
we no longer support. Remove it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit ae82cbfc8b. It
needs the new byteorder headers to be exported to userspace, and
they aren't yet -- and probably shouldn't be, at this point in the
2.6.27 release cycle (or ever, for that matter).
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
The post-index immediate value is optional if it is 0 and this patch
removes it. The reason is to allow such instructions to compile to
Thumb-2 where only pre-indexed LDRT/STRT instructions are allowed.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch adds a config option (CONFIG_VMSPLIT_*) to allow choosing
between 3:1, 2:2 and 1:3 user:kernel memory splits.
Tested-by: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When CONFIG_DEBUG_BUGVERBOSE is not set, we get warnings such as:
arch/arm/mm/ioremap.c: In function ‘remap_area_pte’:
arch/arm/mm/ioremap.c:67: warning: control reaches end of non-void function
mm/bootmem.c: In function ‘mark_bootmem’:
mm/bootmem.c:321: warning: control reaches end of non-void function
fs/dcache.c: In function ‘d_materialise_unique’:
fs/dcache.c:1875: warning: control reaches end of non-void function
fs/nfs/client.c: In function ‘nfs_sockaddr_match_ipaddr’:
fs/nfs/client.c:251: warning: control reaches end of non-void function
block/cfq-iosched.c: In function ‘cfq_async_queue_prio’:
block/cfq-iosched.c:1501: warning: control reaches end of non-void function
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Linux/ARM currently doesn't support robust or PI futexes.
The problem is that the kernel wants to perform certain ops
(cmpxchg, set, add, or, andn, xor) atomically on user-space
addresses, and ARM's futex.h doesn't support that.
This patch adds that support, but only for uniprocessor machines.
For UP it's enough to disable preemption to ensure mutual exclusion
with other software agents (futexes don't need to care about other
hardware agents, fortunately).
This patch is based on one posted by Khem Raj on 2007-08-01
<http://marc.info/?l=linux-arm-kernel&m=118599407413016&w=2>.
(That patch is included in the -RT kernel patches.)
My changes since that version include:
* corrected implementation of FUTEX_OP_ANDN (must complement oparg)
* added missing memory clobber to futex_atomic_cmpxchg_inatomic()
* removed spinlock because it's unnecessary for UP and insufficient
for SMP, instead the code is restricted to UP and relies on the
fact that pagefault_disable() also disables preemption
* coding style cleanups
Tested on ARMv5 XScales with the glibc-2.6 nptl test suite.
Tested-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As mentioned in commit 796969104c,
and because of commit b03a5b7559,
the direct calling of kprobe_trap_handler() can be removed.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than pollute asm/cacheflush.h with the cache type definitions,
move them to asm/cachetype.h, and include this new header where
necessary.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add asm/cputype.h, moving functions and definitions from asm/system.h
there. Convert all users of 'processor_id' to the more efficient
read_cpuid_id() function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* master.kernel.org:/home/rmk/linux-2.6-arm: (38 commits)
[ARM] 5191/1: ARM: remove CVS keywords
[ARM] pxafb: fix the warning of incorrect lccr when lcd_conn is specified
[ARM] pxafb: add flag to specify output format on LDD pins when base is RGBT16
[ARM] pxafb: fix the incorrect configuration of GPIO77 as ACBIAS for TFT LCD
[ARM] 5198/1: PalmTX: PCMCIA fixes
[ARM] Fix a pile of broken watchdog drivers
[ARM] update mach-types
[ARM] 5196/1: fix inline asm constraints for preload
[ARM] 5194/1: update .gitignore
[ARM] add proc-macros.S include to proc-arm940 and proc-arm946
[ARM] 5192/1: ARM TLB: add v7wbi_{possible,always}_flags to {possible,always}_tlb_flags
[ARM] 5193/1: Wire up missing syscalls
[ARM] traps: don't call undef hook functions with spinlock held
[ARM] 5183/2: Provide Poodle LoCoMo GPIO names
[ARM] dma-mapping: provide sync_range APIs
[ARM] dma-mapping: improve type-safeness of DMA translations
[ARM] Kirkwood: instantiate the orion_spi driver in the platform code
[ARM] prevent crashing when too much RAM installed
[ARM] Kirkwood: Instantiate mv_xor driver
[ARM] Orion: Instantiate mv_xor driver for 5182
...
This patch removes CVS keywords that weren't updated for a long time.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With gcc 4.3 and later, a pointer that has already been dereferenced is
assumed not to be null since it should have caused a segmentation fault
otherwise, hence any subsequent test against NULL is optimized away.
Current inline asm constraint used in the implementation of prefetch()
makes gcc believe that the pointer is dereferenced even though the PLD
instruction does not load any data and does not cause a segmentation
fault on null pointers, which causes all sorts of interesting results
when reaching the end of a linked lists for example.
Let's use a better constraint to properly represent the actual usage of
the pointer value.
Problem reported by Chris Steel.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rename KEXEC_CONTROL_CODE_SIZE to KEXEC_CONTROL_PAGE_SIZE, because control
page is used for not only code on some platform. For example in kexec
jump, it is used for data and stack too.
[akpm@linux-foundation.org: unbreak powerpc and arm, finish conversion]
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 2ccdd1e77d doesn't add
v7wbi_possible_flags and v7wbi_always_flags to possible_tlb_flags and
always_tlb_flags. This causes the L2 cache flush in clean_pmd_entry()
(intended for Feroceon only) to execute on ARMv7, and the CPU hangs.
This patch is required for OMAP3 boards to boot.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Setup some missing syscall pointed out by the checksyscalls.sh script. Fix two
small whitespace issues while being there.
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert the existing dma_sync_single_for_* APIs to the new range based
APIs, and make the dma_sync_single_for_* API a superset of it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
OMAP at least gets the return type(s) for the DMA translation functions
wrong, which can lead to subtle errors. Avoid this by moving the DMA
translation functions to asm/dma-mapping.h, and converting them to
inline functions.
Fix the OMAP DMA translation macros to use the correct argument and
result types.
Also, remove the unnecessary casts in dmabounce.c.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch will truncate and/or ignore memory banks if their kernel
direct mappings would (partially) overlap with the vmalloc area or
the mappings between the vmalloc area and the address space top, to
prevent crashing during early boot if there happens to be more RAM
installed than we are expecting.
Since the start of the vmalloc area is not at a fixed address (but
the vmalloc end address is, via the per-platform VMALLOC_END define),
a default area of 128M is reserved for vmalloc mappings, which can
be shrunk or enlarged by passing an appropriate vmalloc= command line
option as it is done on x86.
On a board with a 3:1 user:kernel split, VMALLOC_END at 0xfe000000,
two 512M RAM banks and vmalloc=128M (the default), this patch gives:
Truncating RAM at 20000000-3fffffff to -35ffffff (vmalloc region overlap).
Memory: 512MB 352MB = 864MB total
On a board with a 3:1 user:kernel split, VMALLOC_END at 0xfe800000,
two 256M RAM banks and vmalloc=768M, this patch gives:
Truncating RAM at 00000000-0fffffff to -0e7fffff (vmalloc region overlap).
Ignoring RAM at 10000000-1fffffff (vmalloc region overlap).
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Tested-by: Riku Voipio <riku.voipio@iki.fi>
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h.
Then, since asm/hardware.h only exists to include asm/arch/hardware.h,
update everything to directly include asm/arch/hardware.h and remove
asm/hardware.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Nicolas Pitre