On ARMv6 and later CPUs, it is possible for userspace processes to
get stuck on a misaligned load or store due to the "ignore fault"
setting; unlike previous CPUs, retrying the instruction without
the 'A' bit set does not always cause the load to succeed.
We have no real option but to default to fixing up alignment faults
on these CPUs, and having the CPU fix up those misaligned accesses
which it can.
Reported-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Mikael Pettersson reported:
The 2.6.28-rc kernels fail to detect PCI device 0000:00:01.0
(the first ethernet port) on my Thecus n2100 XScale box.
There is however still a strange "ghost" device that gets partially
detected in 2.6.28-rc2 vanilla.
The IOP321 manual says:
The user designates the memory region containing the OCCDR as
non-cacheable and non-bufferable from the IntelR XScaleTM core.
This guarantees that all load/stores to the OCCDR are only of
DWORD quantities.
Ensure that the OCCDR is so mapped.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Same fix as commit c7cf72dcad: when 'start' and 'end' are less than a
cacheline apart and 'start' is unaligned we are done after cleaning and
invalidating the first cacheline.
Cc: <stable@kernel.org>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When 'start' and 'end' are less than a cacheline apart and 'start' is
unaligned we are done after cleaning and invalidating the first
cacheline. So check for (start < end) which will not walk off into
invalid address ranges when (start > end).
This issue was caught by drivers/dma/dmatest.
2.6.27 is susceptible.
Cc: <stable@kernel.org>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Lothar WaÃ<9f>mann <LW@KARO-electronics.de>
Cc: Lennert Buytenhek <buytenh@marvell.com>
Cc: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
As a result of the ptebits changes, we ended up marking device mappings
as normal memory on ARMv7 CPUs, resulting in undesirable behaviour with
serial ports and the like. While reviewing the section mapping table
entries, other errors in the memory type settings for devices were
detected and confirmed to prevent Xscale3 platforms booting.
Tested on:
OMAP34xx (ARMv7),
OMAP24xx (ARMv6),
OMAP16xx (ARM926T, ARMv5),
PXA311 (Xscale3),
PXA272 (Xscale),
PXA255 (Xscale),
IXP42x (Xscale),
S3C2410 (ARM920T, ARMv4T),
ARM720T (ARMv4T)
StrongARM-110 (ARMv4)
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Tested-by: Mike Rapoport <mike@compulab.co.il>
Tested-by: Ben Dooks <ben-linux@fluff.org>
Tested-by: Anders Grafström <grfstrm@users.sourceforge.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As of 73bdf0a60e, the kernel needs
to know where modules are located in the virtual address space.
On ARM, we located this region between MODULE_START and MODULE_END.
Unfortunately, everyone else calls it MODULES_VADDR and MODULES_END.
Update ARM to use the same naming, so is_vmalloc_or_module_addr()
can work properly. Also update the comment on mm/vmalloc.c to
reflect that ARM also places modules in a separate region from the
vmalloc space.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 40df2d1d "[ARM] Update Xscale and Xscale3 PTE mappings" was
fingered by git-bisect for a boot failure on iop13xx. The change made
L_PTE_MT_WRITETHROUGH mappings L2-uncacheable. Russell points out that
this mapping is used for the vector page. Given the regression, and the
fact this page is used often, restore the old behaviour.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
A typo caused these values to be swapped leading to incorrect memory
type attributes.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The MSM architecture covers a wider family of chips than just the MSM7X00A.
Move to a more generic name, in perparation for supporting the specific
SoC variants as sub-architectures (ARCH_MSM7X01A, ARCH_MSM722X, etc). This
gives us ARCH_MSM for the (many) common peripherals.
This also removes the unused/obsolete config item MSM7X00A_IDLE.
Signed-off-by: Brian Swetland <swetland@google.com>
ARMv4 (ARM720T) cache flush functions are broken in 2.6.19+ kernels.
The issue was introduced by commit f12d0d7c77
This patch corrects the CPU_CP15 ifdef statements so that they actually
do something.
Signed-off-by: Anders Grafström <grfstrm@users.sourceforge.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add minimal Beagle board support. Based on earlier patches
by Syed Mohammed Khasim with some fixes from linux-omap tree.
Signed-off-by: Syed Mohammed Khasim <khasim@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
These instructions were placed in the code directly as opcodes because
early compilers didn't support them. Toolchains supporting ARMv7
understand these instructions and the patch puts the mnemonics back.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
... including some comments about the ordering required to bring
sparsemem up. You have to repeatedly guess, test, reguess, try
again and again to work out what the right ordering is. Many
hours later...
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide helpers for getting physical addresses or pfns from the
meminfo array, and use them. Move for_each_nodebank() to
asm/setup.h alongside the meminfo structure definition.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As of the previous commit, MT_DEVICE_IXP2000 encodes to the same
PTE bit encoding as MT_DEVICE, so it's now redundant. Convert
MT_DEVICE_IXP2000 to use MT_DEVICE instead, and remove its aliases.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide L_PTE_MT_xxx definitions to describe the memory types that we
use in Linux/ARM. These definitions are carefully picked such that:
1. their LSBs match what is required for pre-ARMv6 CPUs.
2. they all have a unique encoding, including after modification
by build_mem_type_table() (the result being that some have more
than one combination.)
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There are actually only four separate implementations of set_pte_ext.
Use assembler macros to insert code for these into the proc-*.S files.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There's no point scattering this around the tree, the parsing
of the parameter might as well live beside the code which uses
it. That also means we can make vmalloc_reserve a static
variable.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The newly introduced sanity_check_meminfo() function should be
used to collect all validation of the meminfo array, which we
have in bootmem_init(). Move it there.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
- Make sure that coprocessor instructions for range ops are contiguous
and not reordered.
- s/invalidate_and_disable_dcache/flush_and_disable_dcache/
- Don't re-enable I/D caches if they were not enabled initially.
- Change some masks to shifts for better generated code.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Acked-by: Lennert Buytenhek <buytenh@marvell.com>
The PTRS_PER_PMD != 1 condition can be evaluated with C code and
optimized at compile time.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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>
Feroceon L2 cache can work in eighther write through or write back mode
on Kirkwood. Add the option to configure this mode according to Kconfig.
Signed-off-by: Ronen Shitrit <rshitrit@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
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>
arch/arm/kernel/process.c:270:6: warning: symbol 'show_fpregs' was not declared. Should it be static?
This function isn't used, so can be removed.
arch/arm/kernel/setup.c:532:9: warning: symbol 'len' shadows an earlier one
arch/arm/kernel/setup.c:524:6: originally declared here
A function containing two 'len's.
arch/arm/mm/fault-armv.c:188:13: warning: symbol 'check_writebuffer_bugs' was not declared. Should it be static?
arch/arm/mm/mmap.c:122:5: warning: symbol 'valid_phys_addr_range' was not declared. Should it be static?
arch/arm/mm/mmap.c:137:5: warning: symbol 'valid_mmap_phys_addr_range' was not declared. Should it be static?
Missing includes.
arch/arm/kernel/traps.c:71:77: warning: Using plain integer as NULL pointer
arch/arm/mm/ioremap.c:355:46: error: incompatible types in comparison expression (different address spaces)
Sillies.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This declaration specifies the "function" type and size for various
assembly functions, mainly needed for generating the correct branch
instructions in Thumb-2.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.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>
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>
