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64,840 commits

Author SHA1 Message Date
Becky Bruce
41caebd123 powerpc: Enable Hugetlb by default for 32-bit 85xx/corenet
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:23 +11:00
Becky Bruce
a475c8ecc6 powerpc: Kconfig updates for FSL BookE HUGETLB 64-bit
Allow hugetlb to be enabled on 64b FSL_BOOK3E.  No platforms enable
it by default yet.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:23 +11:00
Becky Bruce
a6146888be powerpc: Add gpages reservation code for 64-bit FSL BOOKE
For 64-bit FSL_BOOKE implementations, gigantic pages need to be
reserved at boot time by the memblock code based on the command line.
This adds the call that handles the reservation, and fixes some code
comments.

It also removes the previous pr_err when reserve_hugetlb_gpages
is called on a system without hugetlb enabled - the way the code is
structured, the call is unconditional and the resulting error message
spurious and confusing.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:23 +11:00
Becky Bruce
d1b9b12811 powerpc: Add hugepage support to 64-bit tablewalk code for FSL_BOOK3E
Before hugetlb, at each level of the table, we test for
!0 to determine if we have a valid table entry.  With hugetlb, this
compare becomes:
        < 0 is a normal entry
        0 is an invalid entry
        > 0 is huge

This works because the hugepage code pulls the top bit off the entry
(which for non-huge entries always has the top bit set) as an
indicator that we have a hugepage.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:22 +11:00
Becky Bruce
27609a42ee powerpc: Whitespace/comment changes to tlb_low_64e.S
I happened to comment this code while I was digging through it;
we might as well commit that.  I also made some whitespace
changes - the existing code had a lot of unnecessary newlines
that I found annoying when I was working on my tiny laptop.

No functional changes.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:22 +11:00
Becky Bruce
881fde1db5 powerpc: hugetlb: modify include usage for FSL BookE code
The original 32-bit hugetlb implementation used PPC64 vs PPC32 to
determine which code path to take.  However, the final hugetlb
implementation for 64-bit FSL ended up shared with the FSL
32-bit code so the actual check needs to be FSL_BOOK3E vs
everything else.  This patch changes the include protections to
reflect this.

There are also a couple of related comment fixes.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:22 +11:00
Becky Bruce
a1cd541988 powerpc: Update hugetlb huge_pte_alloc and tablewalk code for FSL BOOKE
This updates the hugetlb page table code to handle 64-bit FSL_BOOKE.
The previous 32-bit work counted on the inner levels of the page table
collapsing.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:22 +11:00
Becky Bruce
8c1674de2b powerpc: Fix booke hugetlb preload code for PPC_MM_SLICES and 64-bit
This patch does 2 things: It corrects the code that determines the
size to write into MAS1 for the PPC_MM_SLICES case (this originally
came from David Gibson and I had incorrectly altered it), and it
changes the methodolody used to calculate the size for !PPC_MM_SLICES
to work for 64-bit as well as 32-bit.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:21 +11:00
Becky Bruce
97632e6fbe powerpc: hugetlb: fix huge_ptep_set_access_flags return value
There was an unconditional return of "1" in the original code
from David Gibson, and I dropped it because it wasn't needed
for FSL BOOKE 32-bit.  However, not all systems (including 64-bit
FSL BOOKE) do loading of the hpte from the fault handler asm
and depend on this function returning 1, which causes a call
to update_mmu_cache() that writes an entry into the tlb.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:21 +11:00
Becky Bruce
7651295944 powerpc: Only define HAVE_ARCH_HUGETLB_UNMAPPED_AREA if PPC_MM_SLICES
If we don't have slices, we should be able to use the generic
hugetlb_get_unmapped_area() code

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:21 +11:00
Kyle Moffett
09dc34a95b powerpc/mpic: Add in-core support for cascaded MPICs
The Cell and PowerMac platforms use virtually identical cascaded-IRQ
setup code, so just merge it into the core.  Ideally this code would
trigger automatically when an MPIC device-node specifies an "interrupts"
property, perhaps even enabling MPIC_SECONDARY along the way.

Unfortunately, Benjamin Herrenschmidt has had bad experiences in the
past with the quality of Apple PowerMac device-trees, so to be safe we
will only try to parse out an IRQ if the MPIC_SECONDARY flag is set by
the caller.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:09 +11:00
Kyle Moffett
c51242e708 powerpc/mpic: Cache the device-tree node in "struct mpic"
Store the node pointer in the MPIC during initialization so that all of
the later operational code can just reuse the cached pointer.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:08 +11:00
Kyle Moffett
c579bc766a powerpc/mpic: Put "pic-no-reset" test back into the MPIC code
There's not really any reason to have this one-liner in a separate
static inline function, given that all the other similar tests are
already in the alloc_mpic() code.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:08 +11:00
Kyle Moffett
e62b760179 powerpc/mpic: Don't open-code dcr_resource_start
Don't open-code the OpenFirmware "dcr-reg" property lookup trying to map
DCR resources.  This makes the code a bit easier to read.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:08 +11:00
Kyle Moffett
be8bec56df powerpc/mpic: Invert the meaning of MPIC_PRIMARY
It turns out that there are only 2 in-tree platforms which use MPICs
which are not "primary":  IBM Cell and PowerMac.  To reduce the
complexity of the typical board setup code, invert the MPIC_PRIMARY bit
into MPIC_SECONDARY.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:08 +11:00
Kyle Moffett
996983b75c powerpc/mpic: Search for open-pic device-tree node if NULL
Almost all PowerPC platforms use a standard "open-pic" device node so
the mpic_alloc() function now accepts NULL for the device-node.  This
will cause it to perform a default search with of_find_matching_node().

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:07 +11:00
Kyle Moffett
e7a98675ca powerpc/mpic: Save computed phys_addr for board-specific code
The MPIC code can already perform an automatic OF address translation
step as part of mpic_alloc(), but several boards need to use that base
address when they perform mpic_assign_isu().

The easiest solution is to save the computed physical address into the
"struct mpic" for later use by the board code.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:07 +11:00
Kyle Moffett
5bdb6f2e58 powerpc/mpic: Assume a device-node was passed in mpic_alloc()
All of the existing callers of mpic_alloc() pass in a non-NULL
device-node pointer, so the checks for a NULL device-node may be
removed.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:07 +11:00
Kyle Moffett
8bf4156896 powerpc: Consolidate mpic_alloc() OF address translation
Instead of using the open-coded "reg" property lookup and address
translation in mpic_alloc(), directly call of_address_to_resource().
This includes various workarounds for special cases which the naive
of_address_translate() does not.

Afterwards it is possible to remove the copiously copy-pasted calls to
of_address_translate() from the 85xx/86xx/powermac platforms.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:06 +11:00
Kyle Moffett
582d3e0994 powerpc/85xx: Move mpc85xx_smp_init() decl to a new "smp.h"
This removes a bunch of "extern" declarations and CONFIG_SMP ifdefs.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:06 +11:00
David S. Miller
959327c784 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2011-12-06 21:10:05 -05:00
Rafael J. Wysocki
e84b2c2027 PM / Domains: Make it possible to assign names to generic PM domains
Add a name member pointer to struct generic_pm_domain and use it in
diagnostic messages regarding the domain power-off and power-on
latencies.  Update the ARM shmobile SH7372 code to assign names to
the PM domains used by it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
2011-12-06 22:19:54 +01:00
Russell King
3ee0fc5ca1 Merge branch 'kexec/idmap' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into devel-stable 2011-12-06 20:27:54 +00:00
Tony Lindgren
deee6d5359 ARM: 7194/1: OMAP: Fix build after a merge between v3.2-rc4 and ARM restart changes
ARM restart changes needed changes to common.h to make it local.
This conflicted with v3.2-rc4 DSS related hwmod changes that
git mergetool was not able to handle.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06 20:27:02 +00:00
Don Zickus
565cbc3e93 x86, NMI: NMI-selftest should handle the UP case properly
If no remote cpus are online, then just quietly skip the remote
IPI test for now.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: andi@firstfloor.org
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: robert.richter@amd.com
Link: http://lkml.kernel.org/r/20111206180859.GR1669@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 21:02:39 +01:00
Gleb Natapov
b3d9468a8b perf, x86: Expose perf capability to other modules
KVM needs to know perf capability to decide which PMU it can expose to a
guest.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1320929850-10480-8-git-send-email-gleb@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 20:41:08 +01:00
Peter Zijlstra
c1d6f42f1a perf, x86: Implement arch event mask as quirk
Implement the disabling of arch events as a quirk so that we can print
a message along with it. This creates some visibility into the problem
space and could allow us to work on adding more work-around like the
AAJ80 one.

Requested-by: Ingo Molnar <mingo@elte.hu>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-wcja2z48wklzu1b0nkz0a5y7@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 20:41:06 +01:00
Gleb Natapov
ffb871bc91 x86, perf: Disable non available architectural events
Intel CPUs report non-available architectural events in cpuid leaf
0AH.EBX. Use it to disable events that are not available according
to CPU.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1320929850-10480-7-git-send-email-gleb@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 20:41:05 +01:00
Peter Zijlstra
9cdbe1cbac jump_label, x86: Fix section mismatch
WARNING: arch/x86/kernel/built-in.o(.text+0x4c71): Section mismatch in
reference from the function arch_jump_label_transform_static() to the
function .init.text:text_poke_early()
The function arch_jump_label_transform_static() references
the function __init text_poke_early().
This is often because arch_jump_label_transform_static lacks a __init
annotation or the annotation of text_poke_early is wrong.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jason Baron <jbaron@redhat.com>
Link: http://lkml.kernel.org/n/tip-9lefe89mrvurrwpqw5h8xm8z@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 20:41:02 +01:00
Geert Uytterhoeven
5bf1e97dc3 m68k: Wire up process_vm_{read,write}v
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Greg Ungerer <gerg@uclinux.org>
2011-12-06 20:37:58 +01:00
Arnd Bergmann
3642a0a2c7 Merge branch 'mxs/saif' into next/drivers
Conflicts:
	drivers/net/ethernet/cadence/Kconfig
2011-12-06 14:23:35 +00:00
Arnd Bergmann
24e71ef6d9 Merge branch 'fixes' of git://gitorious.org/linux-davinci/linux-davinci into fixes 2011-12-06 14:20:13 +00:00
Arnd Bergmann
af72617279 Merge branch 'mxs/fixes' of git://git.linaro.org/people/shawnguo/linux-2.6 into fixes 2011-12-06 14:18:36 +00:00
Arnd Bergmann
58a394b3fa Merge branch 'fixes' of git://gitorious.org/sirfprima2-kernel/sirfprima2-kernel into fixes 2011-12-06 14:17:22 +00:00
Arnd Bergmann
fec607aab5 Merge branch 'imx/fix-irqdomain' of git://git.linaro.org/people/shawnguo/linux-2.6 into fixes 2011-12-06 14:15:02 +00:00
Arnd Bergmann
e6b6edf267 Merge branch 'at91-fixes' of git://github.com/at91linux/linux-at91 into fixes 2011-12-06 14:14:06 +00:00
Will Deacon
4e8ee7de22 ARM: SMP: use idmap_pgd for mapping MMU enable during secondary booting
The ARM SMP booting code allocates a temporary set of page tables
containing an identity mapping of the kernel image and provides this
to secondary CPUs for initial booting.

In reality, we only need to include the __turn_mmu_on function in the
identity mapping since the rest of the kernel is executing from virtual
addresses after this point.

This patch adds __turn_mmu_on to the .idmap.text section, allowing the
SMP booting code to use the idmap_pgd directly and not have to populate
its own set of page table.

As a result of this patch, we can make the identity_mapping_add function
static (since it is only used within mm/idmap.c) and also remove the
identity_mapping_del function. The identity map population is moved to
an early initcall so that it is setup in time for secondary CPU bringup.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06 14:04:15 +00:00
Will Deacon
72662e0108 ARM: head.S: only include __turn_mmu_on in the initial identity mapping
__create_page_tables identity maps the region of memory from
__enable_mmu to the end of __turn_mmu_on.

In preparation for including __turn_mmu_on in the .idmap.text section,
this patch modifies the identity mapping so that it only includes the
__turn_mmu_on code.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06 14:04:15 +00:00
Will Deacon
2c8951ab0c ARM: idmap: use idmap_pgd when setting up mm for reboot
For soft-rebooting a system, it is necessary to map the MMU-off code
with an identity mapping so that execution can continue safely once the
MMU has been switched off.

Currently, switch_mm_for_reboot takes out a 1:1 mapping from 0x0 to
TASK_SIZE during reboot in the hope that the reset code lives at a
physical address corresponding to a userspace virtual address.

This patch modifies the code so that we switch to the idmap_pgd tables,
which contain a 1:1 mapping of the cpu_reset code. This has the
advantage of only remapping the code that we need and also means we
don't need to worry about allocating a pgd from an atomic context in the
case that the physical address of the cpu_reset code aliases with the
virtual space used by the kernel.

Acked-by: Dave Martin <dave.martin@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06 14:04:15 +00:00
Will Deacon
1a4baafa7d ARM: proc-*.S: place cpu_reset functions into .idmap.text section
The CPU reset functions disable the MMU and therefore must be executed
with an identity mapping in place.

This patch places the CPU reset functions into the .idmap.text section,
causing the idmap code to include them as part of the identity mapping.

Acked-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06 14:04:14 +00:00
Will Deacon
e6eadc6787 ARM: suspend: use idmap_pgd instead of suspend_pgd
The ARM CPU suspend code requires cpu_resume_mmu to be identity mapped
in order to re-enable the MMU when coming out of suspend. Currently,
this is accomplished by maintaining a suspend_pgd with the relevant
mapping put in place at init time.

This patch replaces the use of suspend_pgd with the new idmap_pgd.
cpu_resume_mmu is placed in the .idmap.text section so that it is
included in the identity map.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06 14:04:14 +00:00
Will Deacon
8903826d0c ARM: idmap: populate identity map pgd at init time using .init.text
When disabling and re-enabling the MMU, it is necessary to take out an
identity mapping for the code that manipulates the SCTLR in order to
avoid it disappearing from under our feet. This is useful when soft
rebooting and returning from CPU suspend.

This patch allocates a set of page tables during boot and populates them
with an identity mapping for the .idmap.text section. This means that
users of the identity map do not need to manage their own pgd and can
instead annotate their functions with __idmap or, in the case of assembly
code, place them in the correct section.

Acked-by: Dave Martin <dave.martin@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-12-06 14:04:14 +00:00
Alan Cox
4e2b1c4f56 x86/intel_mid: Kconfig select fix
If we select a symbol it should have a type declared first
otherwise in some situations the config tools get upset. They
are currently perhaps a bit too resilient which is why this
wasn't noticed initially.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/r/20111206132811.4041.32549.stgit@bob.linux.org.uk
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-06 14:40:50 +01:00
Will Deacon
6bd054096d ARM: 7185/1: perf: don't assign platform_device on unsupported CPUs
In the unlikely case that a platform registers a PMU platform_device
when running on a CPU that is unsupported by perf, we will encounter a
NULL dereference when trying to assign the platform_device to the
cpu_pmu structure.

This patch checks that the CPU is supported by perf before assigning
the platform_device.

Reported-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06 12:48:01 +00:00
Tony Lindgren
16edc3df8a ARM: 7192/1: OMAP: Fix build error for omap1_defconfig
Otherwise we get the following error:

In function 'omap_init_consistent_dma_size':
error: implicit declaration of function 'init_consistent_dma_size'

Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06 12:43:53 +00:00
Denis Kuzmenko
8e146f547a ARM: S3C2440: Add new LCD (W35i) support for Mini2440 board
Signed-off-by: Denis Kuzmenko <linux@solonet.org.ua>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2011-12-06 20:21:54 +09:00
Uwe Kleine-König
de66a97901 ARM: 7187/1: fix unwinding for XIP kernels
The linker places the unwind tables in readonly sections. So when using
an XIP kernel these are located in ROM and cannot be modified.
For that reason the current approach to convert the relative offsets in
the unwind index to absolute addresses early in the boot process doesn't
work with XIP.

The offsets in the unwind index section are signed 31 bit numbers and
the structs are sorted by this offset. So it first has offsets between
0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets
between 0x00000000 and 0x3fffffff. When seperating these two blocks the
numbers are sorted even when interpreting the offsets as unsigned longs.

So determine the first non-negative entry once and track that using the
new origin pointer. The actual bisection can then use a plain unsigned
long comparison. The only thing that makes the new bisection more
complicated is that the offsets are relative to their position in the
index section, so the key to search needs to be adapted accordingly in
each step.

Moreover several consts are added to catch future writes and rename the
member "addr" of struct unwind_idx to "addr_offset" to better match the
new semantic. (This has the additional benefit of breaking eventual
users at compile time to make them aware of the change.)

In my tests the new algorithm was a tad faster than the original and has
the additional upside of not needing the initial conversion and so saves
some boot time and it's possible to unwind even earlier.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06 11:16:13 +00:00
Nicolas Pitre
974c07249b ARM: 7186/1: fix Kconfig issue with PHYS_OFFSET and !MMU
Commit 1b9f95f8ad (ARM: prepare for removal of a bunch of <mach/memory.h>
files) introduced CONFIG_PHYS_OFFSET but the Kconfig hex prompt did not
provide a default value.

This has the undesired side effect of breaking a reportedly used
trick for updating defconfigs on the fly for routine buildtesting
across all arch and all platforms, i.e.

	cp /path/to/somedefconfig .config ; yes "" | make oldconfig

because the config system will endlessly loop until a valid address is
provided.

However we can't just pick a random default value since it is likely to
be wrong for the majority of the boards as the right answer for this
option is quite varied.  So the fact that the config system insists on
having a proper value be entered is actually a good thing.

It turns out that only at91x40_defconfig has this problem because it has
CONFIG_MMU=n. However, in the !MMU case, there is already a CONFIG_DRAM_BASE
value that can be used here.  So let's use that as a default in that case
and suppress the redundant CONFIG_PHYS_OFFSET prompt.

Eventually the DRAM_BASE config option could simply be replaced by
PHYS_OFFSET directly, but that's a larger change better suited for later.

Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06 11:16:13 +00:00
Kautuk Consul
8878a539ff ARM: 7178/1: fault.c: Port OOM changes into do_page_fault
Commit d065bd810b
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e0525
(x86,mm: make pagefault killable)

The above commits introduced changes into the x86 pagefault handler
for making the page fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial
during OOM killer invocation.

Port these changes to ARM.

Without these changes, my ARM board encounters many hang and livelock
scenarios.
After applying this patch, OOM feature performance improves according to
my testing.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06 11:15:26 +00:00
Dave Martin
df0e74da6d ARM: 7173/1: Add optimised swahb32() byteswap helper for v6 and above
ARMv6 and later processors have the REV16 instruction, which swaps
the bytes within each halfword of a register value.

This is already used to implement swab16(), but since the native
operation performaed by REV16 is actually swahb32(), this patch
renames the existing swab16() helper accordingly and defines
__arch_swab16() in terms of it.  This allows calls to both swab16()
and swahb32() to be optimised.

The compiler's generated code might improve someday, but as of
4.5.2 the code generated for pure C implementing these 16-bit
bytesswaps remains pessimal.

swahb32() is useful for converting 32-bit Thumb instructions
between integer and memory representation on BE8 platforms (among
other uses).

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06 11:15:26 +00:00