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commit 39544ac9df20f73e49fc6b9ac19ff533388c82c0 upstream.
Add DSB after icache flush to complete the cache maintenance operation.
Signed-off-by: Vinayak Kale <vkale@apm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 7c8746a9eb287642deaad0e7c2cdf482dce5e4be upstream.
When unlocking a spinlock, we require the following, strictly ordered
sequence of events:
<barrier> /* dmb */
<unlock>
<barrier> /* dsb */
<sev>
Whilst the code does indeed reflect this in terms of the architecture,
the final <barrier> + <sev> have been contracted into a single inline
asm without a "memory" clobber, therefore the compiler is at liberty to
reorder the unlock to the end of the above sequence. In such a case,
a waiting CPU may be woken up before the lock has been unlocked, leading
to extremely poor performance.
This patch reworks the dsb_sev() function to make use of the dsb()
macro and ensure ordering against the unlock.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: 'ishst' variant is not used here]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit bae0ca2bc550d1ec6a118fb8f2696f18c4da3d8e upstream.
During __v{6,7}_setup, we invalidate the TLBs since we are about to
enable the MMU on return to head.S. Unfortunately, without a subsequent
dsb instruction, the invalidation is not guaranteed to have completed by
the time we write to the sctlr, potentially exposing us to junk/stale
translations cached in the TLB.
This patch reworks the init functions so that the dsb used to ensure
completion of cache/predictor maintenance is also used to ensure
completion of the TLB invalidation.
Reported-by: Albin Tonnerre <Albin.Tonnerre@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 29c350bf28da333e41e30497b649fe335712a2ab upstream.
The array was missing the final entry for the undefined instruction
exception handler; this commit adds it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 4ff859fe1dc0da0f87bbdfff78f527898878fa4a upstream.
The clockevents code was being told that the footbridge clock event
device ticks at 16x the rate which it actually does. This leads to
timekeeping problems since it allows the clocksource to wrap before
the kernel notices. Fix this by using the correct clock.
Fixes: 4e8d76373c9fd ("ARM: footbridge: convert to clockevents/clocksource")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: fold in the relevant parts of commit 838a2ae80a6a
('ARM: use clockevents_config_and_register() where possible')]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 8404663f81d212918ff85f493649a7991209fa04 upstream.
The {get,put}_user macros don't perform range checking on the provided
__user address when !CPU_HAS_DOMAINS.
This patch reworks the out-of-line assembly accessors to check the user
address against a specified limit, returning -EFAULT if is is out of
range.
[will: changed get_user register allocation to match put_user]
[rmk: fixed building on older ARM architectures]
Reported-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>
[bwh: Backported to 3.2: TUSER() was called T()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit ff88b4724fde18056a4c539f7327389aec0f4c2d upstream.
Erratum 71 of PXA270M Processor Family Specification Update
(April 19, 2010) explains that watchdog reset time is just
8us insead of 10ms in EMTS.
If SDRAM is not reset, it causes memory bus congestion and
the device hangs. We put SDRAM in selfresh mode before watchdog
reset, removing potential freezes.
Without this patch PXA270-based ICP DAS LP-8x4x hangs after up to 40
reboots. With this patch it has successfully rebooted 500 times.
Signed-off-by: Sergei Ianovich <ynvich@gmail.com>
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 506cac15ac86f204b83e3cfccde73eeb4e7c5f34 upstream.
When converting from tosa-keyboard driver to matrix keyboard, tosa keys
received extra 1 column shift. Replace that with correct values to make
keyboard work again.
Fixes: f69a6548c9d5 ('[ARM] pxa/tosa: make use of the matrix keypad driver')
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 3abb6671a9c04479c4bd026798a05f857393b7e2 upstream.
This patch fixes corner case when (fp + 4) overflows unsigned long,
for example: fp = 0xFFFFFFFF -> fp + 4 == 3.
Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 1b15ec7a7427d4188ba91b9bbac696250a059d22 upstream.
get_wchan() is lockless. Task may wakeup at any time and change its own stack,
thus each next stack frame may be overwritten and filled with random stuff.
/proc/$pid/stack interface had been disabled for non-current tasks, see [1]
But 'wchan' still allows to trigger stack frame unwinding on volatile stack.
This patch fixes oops in unwind_frame() by adding stack pointer validation on
each step (as x86 code do), unwind_frame() already checks frame pointer.
Also I've found another report of this oops on stackoverflow (irony).
Link: http://www.spinics.net/lists/arm-kernel/msg110589.html [1]
Link: http://stackoverflow.com/questions/18479894/unwind-frame-cause-a-kernel-paging-error
Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 43659222e7a0113912ed02f6b2231550b3e471ac upstream.
It's no good setting vga_base after the VGA console has been
initialised, because if we do that we get this:
Unable to handle kernel paging request at virtual address 000b8000
pgd = c0004000
[000b8000] *pgd=07ffc831, *pte=00000000, *ppte=00000000
0Internal error: Oops: 5017 [#1] ARM
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.12.0+ #49
task: c03e2974 ti: c03d8000 task.ti: c03d8000
PC is at vgacon_startup+0x258/0x39c
LR is at request_resource+0x10/0x1c
pc : [<c01725d0>] lr : [<c0022b50>] psr: 60000053
sp : c03d9f68 ip : 000b8000 fp : c03d9f8c
r10: 000055aa r9 : 4401a103 r8 : ffffaa55
r7 : c03e357c r6 : c051b460 r5 : 000000ff r4 : 000c0000
r3 : 000b8000 r2 : c03e0514 r1 : 00000000 r0 : c0304971
Flags: nZCv IRQs on FIQs off Mode SVC_32 ISA ARM Segment kernel
which is an access to the 0xb8000 without the PCI offset required to
make it work.
Fixes: cc22b4c18540 ("ARM: set vga memory base at run-time")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 30aeadd44deea3f3b0df45b9a70ee0fd5f8d6dc2 upstream.
This turns on the internal integrator LCD display(s). It seems that the code
to do this got lost in refactoring of the CLCD driver.
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit f3964fe1c9d9a887d65faf594669852e4dec46e0 upstream.
The CS2 region contains the Assabet board configuration and status
registers, which are 32-bit. Unfortunately, some boot loaders do not
configure this region correctly, leaving it setup as a 16-bit region.
Fix this.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 4b59e6c4730978679b414a8da61514a2518da512 upstream.
On large systems with a lot of memory, walking all RAM to determine page
types may take a half second or even more.
In non-blockable contexts, the page allocator will emit a page allocation
failure warning unless __GFP_NOWARN is specified. In such contexts, irqs
are typically disabled and such a lengthy delay may even result in NMI
watchdog timeouts.
To fix this, suppress the page walk in such contexts when printing the
page allocation failure warning.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 99f2b130370b904ca5300079243fdbcafa2c708b upstream.
The SMAP register offsets in the versatile PCI controller code were
all off by four. (This didn't have any observable bad effects
because on this board PHYS_OFFSET is zero, and (a) writing zero to
the flags register at offset 0x10 has no effect and (b) the reset
value of the SMAP register is zero anyway, so failing to write SMAP2
didn't matter.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit b88a2595b6d8aedbd275c07dfa784657b4f757eb upstream.
Fix constraint check in armpmu_map_hw_event().
Reported-and-tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit c95eb3184ea1a3a2551df57190c81da695e2144b upstream.
It is possible to construct an event group with a software event as a
group leader and then subsequently add a hardware event to the group.
This results in the event group being validated by adding all members
of the group to a fake PMU and attempting to allocate each event on
their respective PMU.
Unfortunately, for software events wthout a corresponding arm_pmu, this
results in a kernel crash attempting to dereference the ->get_event_idx
function pointer.
This patch fixes the problem by checking explicitly for software events
and ignoring those in event validation (since they can always be
scheduled). We will probably want to revisit this for 3.12, since the
validation checks don't appear to work correctly when dealing with
multiple hardware PMUs anyway.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit acfdd4b1f7590d02e9bae3b73bdbbc4a31b05d38 upstream.
a.out support on ARM requires that argc, argv and envp are passed in
r0-r2 respectively, which requires hacking load_aout_binary to
prevent argc being clobbered by the return code. Whilst mainline kernels
do set the registers up in start_thread, the aout loader has never
carried the hack in mainline.
Initialising the registers in this way actually goes against the libc
expectations for ELF binaries, where argc, argv and envp are passed on
the stack, with r0 being used to hold a pointer to an exit function for
cleaning up after the dynamic linker if required. If the pointer is
NULL, then it is ignored. When execing an ELF binary, Linux currently
zeroes r0, then sets it to argc and then finally clobbers it with the
return value of the execve syscall, so we actually end up with:
r0 = 0
stack[0] = argc
r1 = stack[1] = argv
r2 = stack[2] = envp
libc treats r1 and r2 as undefined. The clobbering of r0 by sys_execve
works for user-spawned threads, but when executing an ELF binary from a
kernel thread (via call_usermodehelper), the execve is performed on the
ret_from_fork path, which restores r0 from the saved pt_regs, resulting
in argc being presented to the C library. This has horrible consequences
when the application exits, since we have an exit function registered
using argc, resulting in a jump to hyperspace.
This patch solves the problem by removing the partial a.out support from
arch/arm/ altogether.
Cc: Ashish Sangwan <ashishsangwan2@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2:
- Adjust context
- Adjust uapi filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit c5f927a6f62196226915f12194c9d0df4e2210d7 upstream.
With this change, we no longer lose the innermost entry in the user-mode
part of the call chain. See also the x86 port, which includes the ip.
It's possible to partially work around this problem by post-processing
the data to use the PERF_SAMPLE_IP value, but this works only if the CPU
wasn't in the kernel when the sample was taken.
Signed-off-by: Jed Davis <jld@mozilla.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 63384fd0b1509acf522a8a8fcede09087eedb7df upstream.
Commit 1bc3974 (ARM: 7755/1: handle user space mapped pages in
flush_kernel_dcache_page) moved the implementation of
flush_kernel_dcache_page() into mm/flush.c but did not implement it
on noMMU ARM.
Signed-off-by: Simon Baatz <gmbnomis@gmail.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 1bc39742aab09248169ef9d3727c9def3528b3f3 upstream.
Commit f8b63c1 made flush_kernel_dcache_page a no-op assuming that
the pages it needs to handle are kernel mapped only. However, for
example when doing direct I/O, pages with user space mappings may
occur.
Thus, continue to do lazy flushing if there are no user space
mappings. Otherwise, flush the kernel cache lines directly.
Signed-off-by: Simon Baatz <gmbnomis@gmail.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit da94a829305f1c217cfdf6771cb1faca0917e3b9 upstream.
In August 2012, Matthew Gretton-Dann checked a change into binutils
labelled "Error on obsolete & warn on deprecated registers", apparently as
part of ARMv8 support. Apparently, this was supposed to emit the message
"Warning: This coprocessor register access is deprecated in ARMv8" when
using certain mcr/mrc instructions and building for ARMv8. Unfortunately,
the message that is actually emitted appears to be '(null)', which is
less helpful in comparison.
Even more unfortunately, this is biting us on every single kernel
build with a new gas, because arch/arm/boot/compressed/head.S and some
other files in that directory are built with -march=all since kernel
commit 80cec14a8 "[ARM] Add -march=all to assembly file build in
arch/arm/boot/compressed" back in v2.6.28.
This patch reverts Russell's nice solution and instead marks the head.S
file to be built for armv7-a, which fortunately lets us build all
instructions in that file without warnings even on the broken binutils.
Without this patch, building anything results in:
arch/arm/boot/compressed/head.S: Assembler messages:
arch/arm/boot/compressed/head.S:565: Warning: (null)
arch/arm/boot/compressed/head.S:676: Warning: (null)
arch/arm/boot/compressed/head.S:698: Warning: (null)
arch/arm/boot/compressed/head.S:722: Warning: (null)
arch/arm/boot/compressed/head.S:726: Warning: (null)
arch/arm/boot/compressed/head.S:957: Warning: (null)
arch/arm/boot/compressed/head.S:996: Warning: (null)
arch/arm/boot/compressed/head.S:997: Warning: (null)
arch/arm/boot/compressed/head.S:1027: Warning: (null)
arch/arm/boot/compressed/head.S:1035: Warning: (null)
arch/arm/boot/compressed/head.S:1046: Warning: (null)
arch/arm/boot/compressed/head.S:1060: Warning: (null)
arch/arm/boot/compressed/head.S:1092: Warning: (null)
arch/arm/boot/compressed/head.S:1094: Warning: (null)
arch/arm/boot/compressed/head.S:1095: Warning: (null)
arch/arm/boot/compressed/head.S:1102: Warning: (null)
arch/arm/boot/compressed/head.S:1134: Warning: (null)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Gretton-Dann <matthew.gretton-dann@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2:
- Adjust context
- Remove definition of asflags-y as it is now empty]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 92bdd3f5eba299b33c2f4407977d6fa2e2a6a0da upstream.
The cpu_topology symbol is required by any driver using the topology
interfaces, which leads to a couple of build errors:
ERROR: "cpu_topology" [drivers/net/ethernet/sfc/sfc.ko] undefined!
ERROR: "cpu_topology" [drivers/cpufreq/arm_big_little.ko] undefined!
ERROR: "cpu_topology" [drivers/block/mtip32xx/mtip32xx.ko] undefined!
The obvious solution is to export this symbol.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 2b8b2797142c7951e635c6eec5d1705ee9bc45c5 upstream.
When platform data were moved from arch/arm/mach-mv78xx0/common.c to
arch/arm/plat-orion/common.c with the commit "7e3819d ARM: orion:
Consolidate ethernet platform data", there were few typo made on
gigabit Ethernet interface ge10 and ge11. This commit writes back
their initial value, which allows to use this interfaces again.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 99e11334dcb846f9b76fb808196c7f47aa83abb3 upstream.
Enable KW_PCIE1 on QNAP TS-11x/TS-21x devices as newer revisions
(rev 1.3) have a USB 3.0 chip from Etron on PCIe port 1. Thanks
to Marek Vasut for identifying this issue!
Signed-off-by: Martin Michlmayr <tbm@cyrius.com>
Tested-by: Marek Vasut <marex@denx.de>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 91cf54feecf815bec0b6a8d6d9dbd0e219f2f2cc upstream.
Fix regression introduced by commit 796211b7953 ("mmc: atmel-mci: add
pdc support and runtime capabilities detection") which removed the need
for CONFIG_MMC_ATMELMCI_DMA but kept the Kconfig-entry as well as the
compile guards around dma_release_channel() in remove(). Consequently,
DMA is always enabled (if supported), but the DMA-channel is not
released on module unload unless the DMA-config option is selected.
Remove the no longer used CONFIG_MMC_ATMELMCI_DMA option completely.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 0259d9eb30d003af305626db2d8332805696e60d upstream.
The UART1 is on the fast AHB bridge, not on the slow bus.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit cb2d8b342aa084d1f3ac29966245dec9163677fb upstream.
Events may be created with attr->disabled == 1 and attr->enable_on_exec
== 1, which confuses the group validation code because events with the
PERF_EVENT_STATE_OFF are not considered candidates for scheduling, which
may lead to failure at group scheduling time.
This patch fixes the validation check for ARM, so that events in the
OFF state are still considered when enable_on_exec is true.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Reported-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit cd272d1ea71583170e95dde02c76166c7f9017e6 upstream.
On Feroceon the L2 cache becomes non-coherent with the CPU
when the L1 caches are disabled. Thus the L2 needs to be invalidated
after both L1 caches are disabled.
On kexec before the starting the code for relocation the kernel,
the L1 caches are disabled in cpu_froc_fin (cpu_v7_proc_fin for Feroceon),
but after L2 cache is never invalidated, because inv_all is not set
in cache-feroceon-l2.c.
So kernel relocation and decompression may has (and usually has) errors.
Setting the function enables L2 invalidation and fixes the issue.
Signed-off-by: Illia Ragozin <illia.ragozin@grapecom.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit b6c7aabd923a17af993c5a5d5d7995f0b27c000a upstream.
Let's do the changes properly and fix the same problem everywhere, not
just for one case.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: mohawk doesn't support suspend at all]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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flush_signal_handlers() needs to know whether sigaction::sa_restorer
is defined, not whether SA_RESTORER is defined. Define the
__ARCH_HAS_SA_RESTORER macro to indicate this.
Vaguely based on upstream commit 574c4866e33d 'consolidate kernel-side
struct sigaction declarations'.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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commit f2fe09b055e2549de41fb107b34c60bac4a1b0cf upstream.
Masked out PMXEVTYPER.NSH means that we can't enable profiling at PL2,
regardless of the settings in the HDCR.
This patch fixes the broken mask.
Reported-by: Christoffer Dall <cdall@cs.columbia.edu>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit b255188f90e2bade1bd11a986dd1ca4861869f4d upstream.
Paolo Pisati reports that IPv6 triggers this warning:
BUG: scheduling while atomic: swapper/0/0/0x40000100
Modules linked in:
[<c001b1c4>] (unwind_backtrace+0x0/0xf0) from [<c0503c5c>] (__schedule_bug+0x48/0x5c)
[<c0503c5c>] (__schedule_bug+0x48/0x5c) from [<c0508608>] (__schedule+0x700/0x740)
[<c0508608>] (__schedule+0x700/0x740) from [<c007007c>] (__cond_resched+0x24/0x34)
[<c007007c>] (__cond_resched+0x24/0x34) from [<c05086dc>] (_cond_resched+0x3c/0x44)
[<c05086dc>] (_cond_resched+0x3c/0x44) from [<c0021f6c>] (do_alignment+0x178/0x78c)
[<c0021f6c>] (do_alignment+0x178/0x78c) from [<c00083e0>] (do_DataAbort+0x34/0x98)
[<c00083e0>] (do_DataAbort+0x34/0x98) from [<c0509a60>] (__dabt_svc+0x40/0x60)
Exception stack(0xc0763d70 to 0xc0763db8)
3d60: e97e805e e97e806e 2c000000 11000000
3d80: ea86bb00 0000002c 00000011 e97e807e c076d2a8 e97e805e e97e806e 0000002c
3da0: 3d000000 c0763dbc c04b98fc c02a8490 00000113 ffffffff
[<c0509a60>] (__dabt_svc+0x40/0x60) from [<c02a8490>] (__csum_ipv6_magic+0x8/0xc8)
Fix this by using probe_kernel_address() stead of __get_user().
Reported-by: Paolo Pisati <p.pisati@gmail.com>
Tested-by: Paolo Pisati <p.pisati@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 5e4ba617c1b584b2e376f31a63bd4e734109318a upstream.
Martin Storsjö reports that the sequence:
ee312ac1 vsub.f32 s4, s3, s2
ee702ac0 vsub.f32 s5, s1, s0
e59f0028 ldr r0, [pc, #40]
ee111a90 vmov r1, s3
on Raspberry Pi (implementor 41 architecture 1 part 20 variant b rev 5)
where s3 is a denormal and s2 is zero results in incorrect behaviour -
the instruction "vsub.f32 s5, s1, s0" is not executed:
VFP: bounce: trigger ee111a90 fpexc d0000780
VFP: emulate: INST=0xee312ac1 SCR=0x00000000
...
As we can see, the instruction triggering the exception is the "vmov"
instruction, and we emulate the "vsub.f32 s4, s3, s2" but fail to
properly take account of the FPEXC_FP2V flag in FPEXC. This is because
the test for the second instruction register being valid is bogus, and
will always skip emulation of the second instruction.
Reported-by: Martin Storsjö <martin@martin.st>
Tested-by: Martin Storsjö <martin@martin.st>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit fa5ce5f94c0f2bfa41ba68d2d2524298e1fc405e upstream.
New ARM binutils don't allow extraneous whitespace inside
of brackets, which causes this error on all mach-w90x900
defconfigs:
arch/arm/kernel/entry-armv.S: Assembler messages:
arch/arm/kernel/entry-armv.S:214: Error: ARM register expected -- `ldr r0,[ r6,#(0x10C)]'
arch/arm/kernel/entry-armv.S:214: Error: ARM register expected -- `ldr r0,[ r6,#(0x110)]'
arch/arm/kernel/entry-armv.S:430: Error: ARM register expected -- `ldr r0,[ r6,#(0x10C)]'
arch/arm/kernel/entry-armv.S:430: Error: ARM register expected -- `ldr r0,[ r6,#(0x110)]'
This removes the whitespace in order to build the kernel
again.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 2815774bb38445006074e16251b9ef5123bdc616 upstream.
Recent assembler versions complain about extraneous
whitespace inside [] brackets. This fixes all of
these instances for the samsung platforms. We should
backport this to all kernels that might need to
be built with new binutils.
arch/arm/kernel/entry-armv.S: Assembler messages:
arch/arm/kernel/entry-armv.S:214: Error: ARM register expected -- `ldr r2,[ r6,#(0x10)]'
arch/arm/kernel/entry-armv.S:214: Error: ARM register expected -- `ldr r0,[ r6,#(0x14)]'
arch/arm/kernel/entry-armv.S:430: Error: ARM register expected -- `ldr r2,[ r6,#(0x10)]'
arch/arm/kernel/entry-armv.S:430: Error: ARM register expected -- `ldr r0,[ r6,#(0x14)]'
arch/arm/mach-s3c24xx/sleep-s3c2410.S: Assembler messages:
arch/arm/mach-s3c24xx/sleep-s3c2410.S:48: Error: ARM register expected -- `ldr r7,[ r4 ]'
arch/arm/mach-s3c24xx/sleep-s3c2410.S:49: Error: ARM register expected -- `ldr r8,[ r5 ]'
arch/arm/mach-s3c24xx/sleep-s3c2410.S:50: Error: ARM register expected -- `ldr r9,[ r6 ]'
arch/arm/mach-s3c24xx/sleep-s3c2410.S:64: Error: ARM register expected -- `streq r7,[ r4 ]'
arch/arm/mach-s3c24xx/sleep-s3c2410.S:65: Error: ARM register expected -- `streq r8,[ r5 ]'
arch/arm/mach-s3c24xx/sleep-s3c2410.S:66: Error: ARM register expected -- `streq r9,[ r6 ]'
arch/arm/kernel/debug.S: Assembler messages:
arch/arm/kernel/debug.S:83: Error: ARM register expected -- `ldr r2,[ r2,#((0x0B0)+(((0x56000000)-(0x50000000))+(0xF6000000+(0x01000000))))-((0)+(((0x56000000)-(0x50000000))+(0xF6000000+(0x01000000))))]'
arch/arm/kernel/debug.S:83: Error: ARM register expected -- `ldr r2,[ r3,#(0x18)]'
arch/arm/kernel/debug.S:85: Error: ARM register expected -- `ldr r2,[ r2,#((0x0B0)+(((0x56000000)-(0x50000000))+(0xF6000000+(0x01000000))))-((0)+(((0x56000000)-(0x50000000))+(0xF6000000+(0x01000000))))]'
arch/arm/kernel/debug.S:85: Error: ARM register expected -- `ldr r2,[ r3,#(0x18)]'
arch/arm/mach-s3c24xx/pm-h1940.S: Assembler messages:
arch/arm/mach-s3c24xx/pm-h1940.S:33: Error: ARM register expected -- `ldr pc,[ r0,#((0x0B8)+(((0x56000000)-(0x50000000))+(0xF6000000+(0x01000000))))-(((0x56000000)-(0x50000000))+(0xF6000000+(0x01000000)))]'
arch/arm/mach-s3c24xx/sleep-s3c2412.S: Assembler messages:
arch/arm/mach-s3c24xx/sleep-s3c2412.S:60: Error: ARM register expected -- `ldrne r9,[ r1 ]'
arch/arm/mach-s3c24xx/sleep-s3c2412.S:61: Error: ARM register expected -- `strne r9,[ r1 ]'
arch/arm/mach-s3c24xx/sleep-s3c2412.S:62: Error: ARM register expected -- `ldrne r9,[ r2 ]'
arch/arm/mach-s3c24xx/sleep-s3c2412.S:63: Error: ARM register expected -- `strne r9,[ r2 ]'
arch/arm/mach-s3c24xx/sleep-s3c2412.S:64: Error: ARM register expected -- `ldrne r9,[ r3 ]'
arch/arm/mach-s3c24xx/sleep-s3c2412.S:65: Error: ARM register expected -- `strne r9,[ r3 ]'
arch/arm/kernel/debug.S:83: Error: ARM register expected -- `ldr r2,[ r3,#(0x08)]'
arch/arm/kernel/debug.S:83: Error: ARM register expected -- `ldr r2,[ r3,#(0x18)]'
arch/arm/kernel/debug.S:83: Error: ARM register expected -- `ldr r2,[ r3,#(0x10)]'
arch/arm/kernel/debug.S:85: Error: ARM register expected -- `ldr r2,[ r3,#(0x08)]'
arch/arm/kernel/debug.S:85: Error: ARM register expected -- `ldr r2,[ r3,#(0x18)]'
arch/arm/kernel/debug.S:85: Error: ARM register expected -- `ldr r2,[ r3,#(0x10)]'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
[bwh: Backported to 3.2: adjust filenames]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit d107a204154ddd79339203c2deeb7433f0cf6777 upstream.
The Chip Select Configuration Register must be programmed to 0x2 in
order to achieve the correct behavior of the Static Memory Controller.
Without this patch devices wired to DFI and accessed through SMC cannot
be accessed after resume from S2.
Do not rely on the boot loader to program the CSMSADRCFG register by
programming it in the kernel smemc module.
Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 15653371c67c3fbe359ae37b720639dd4c7b42c5 upstream.
Subhash Jadavani reported this partial backtrace:
Now consider this call stack from MMC block driver (this is on the ARMv7
based board):
[<c001b50c>] (v7_dma_inv_range+0x30/0x48) from [<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c)
[<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c) from [<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c)
[<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c) from [<c0017ff8>] (dma_map_sg+0x3c/0x114)
This is caused by incrementing the struct page pointer, and running off
the end of the sparsemem page array. Fix this by incrementing by pfn
instead, and convert the pfn to a struct page.
Suggested-by: James Bottomley <JBottomley@Parallels.com>
Tested-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 6f16f4998f98e42e3f2dedf663cfb691ff0324af upstream.
We currently use a temporary 1MB section aligned to a 1MB boundary for
mapping the provided device tree until the final page table is created.
However, if the device tree happens to cross that 1MB boundary, the end
of it remains unmapped and the kernel crashes when it attempts to access
it. Given no restriction on the location of that DTB, it could end up
with only a few bytes mapped at the end of a section.
Solve this issue by mapping two consecutive sections.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2:
- Adjust context
- The mapping is not conditional; drop the 'ne' suffixes]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 568dca15aa2a0f4ddee255894ec393a159f13147 upstream.
Patrik Kluba reports that the preempt count becomes invalid due
to the preempt_enable() call being unbalanced with a
preempt_disable() call in the vfp assembly routines. This happens
because preempt_enable() and preempt_disable() update preempt
counts under PREEMPT_COUNT=y but the vfp assembly routines do so
under PREEMPT=y. In a configuration where PREEMPT=n and
DEBUG_ATOMIC_SLEEP=y, PREEMPT_COUNT=y and so the preempt_enable()
call in VFP_bounce() keeps subtracting from the preempt count
until it goes negative.
Fix this by always using PREEMPT_COUNT to decided when to update
preempt counts in the ARM assembly code.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reported-by: Patrik Kluba <pkluba@dension.com>
Tested-by: Patrik Kluba <pkluba@dension.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 3b4bc7bccc7857274705b05cf81a0c72cfd0b0dd upstream.
This patch fixes some code that implements a work-around to a hardware bug in
the ac97 controller on the pxa27x. A bug in the controller's warm reset
functionality requires that the mfp used by the controller as the AC97_nRESET
line be temporarily reconfigured as a generic output gpio (AF0) and manually
held high for the duration of the warm reset cycle. This is what was done in
the original code, but it was broken long ago by commit fb1bf8cd
([ARM] pxa: introduce processor specific pxa27x_assert_ac97reset())
which changed the mfp to a GPIO input instead of a high output.
The fix requires the ac97 controller to obtain the gpio via gpio_request_one(),
with arguments that configure the gpio as an output initially driven high.
Tested on a palm treo 680 machine. Reportedly, this broken code only prevents a
warm reset on hardware that lacks a pull-up on the line, which appears to be the
case for me.
Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 7bf9b7bef881aac820bf1f2e9951a17b09bd7e04 upstream.
find_vma() is *not* safe when somebody else is removing vmas. Not just
the return value might get bogus just as you are getting it (this instance
doesn't try to dereference the resulting vma), the search itself can get
buggered in rather spectacular ways. IOW, ->mmap_sem really, really is
not optional here.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 864aa04cd02979c2c755cb28b5f4fe56039171c0 upstream.
When updating the page protection map after calculating the user_pgprot
value, the base protection map is temporarily stored in an unsigned long
type, causing truncation of the protection bits when LPAE is enabled.
This effectively means that calls to mprotect() will corrupt the upper
page attributes, clearing the XN bit unconditionally.
This patch uses pteval_t to store the intermediate protection values,
preserving the upper bits for 64-bit descriptors.
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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CONFIG_VFPv3 set
commit 39141ddfb63a664f26d3f42f64ee386e879b492c upstream.
After commit 846a136881b8f73c1f74250bf6acfaa309cab1f2 ("ARM: vfp: fix
saving d16-d31 vfp registers on v6+ kernels"), the OMAP 2430SDP board
started crashing during boot with omap2plus_defconfig:
[ 3.875122] mmcblk0: mmc0:e624 SD04G 3.69 GiB
[ 3.915954] mmcblk0: p1
[ 4.086639] Internal error: Oops - undefined instruction: 0 [#1] SMP ARM
[ 4.093719] Modules linked in:
[ 4.096954] CPU: 0 Not tainted (3.6.0-02232-g759e00b #570)
[ 4.103149] PC is at vfp_reload_hw+0x1c/0x44
[ 4.107666] LR is at __und_usr_fault_32+0x0/0x8
It turns out that the context save/restore fix unmasked a latent bug
in commit 5aaf254409f8d58229107b59507a8235b715a960 ("ARM: 6203/1: Make
VFPv3 usable on ARMv6"). When CONFIG_VFPv3 is set, but the kernel is
booted on a pre-VFPv3 core, the code attempts to save and restore the
d16-d31 VFP registers. These are only present on non-D16 VFPv3+, so
this results in an undefined instruction exception. The code didn't
crash before commit 846a136 because the save and restore code was
only touching d0-d15, present on all VFP.
Fix by implementing a request from Russell King to add a new HWCAP
flag that affirmatively indicates the presence of the d16-d31
registers:
http://marc.info/?l=linux-arm-kernel&m=135013547905283&w=2
and some feedback from Måns to clarify the name of the HWCAP flag.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@linaro.org>
Cc: Måns Rullgård <mans.rullgard@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 1dc831bf53fddcc6443f74a39e72db5bcea4f15d upstream.
- The code relies on rc_pci_fixup being called, which only happens
when CONFIG_PCI_QUIRKS is enabled, so add that to Kconfig. Omitting
this causes a booting failure with a non-obvious cause.
- Update rc_pci_fixup to set the class properly, copying the
more modern style from other places
- Correct the rc_pci_fixup comment
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit d356cf5a74afa32b40decca3c9dd88bc3cd63eb5 upstream.
PMU interrupts start at IRQ_DOVE_PMU_START, not IRQ_DOVE_PMU_START + 1.
Fix the condition. (It may have been less likely to occur had the code
been written "if (irq >= IRQ_DOVE_PMU_START" which imho is the easier
to understand notation, and matches the normal way of thinking about
these things.)
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 5d3df935426271016b895aecaa247101b4bfa35e upstream.
Fix the acknowledgement of PMU interrupts on Dove: some Dove hardware
has not been sensibly designed so that interrupts can be handled in a
race free manner. The PMU is one such instance.
The pending (aka 'cause') register is a bunch of RW bits, meaning that
these bits can be both cleared and set by software (confirmed on the
Armada-510 on the cubox.)
Hardware sets the appropriate bit when an interrupt is asserted, and
software is required to clear the bits which are to be processed. If
we write ~(1 << bit), then we end up asserting every other interrupt
except the one we're processing. So, we need to do a read-modify-write
cycle to clear the asserted bit.
However, any interrupts which occur in the middle of this cycle will
also be written back as zero, which will also clear the new interrupts.
The upshot of this is: there is _no_ way to safely clear down interrupts
in this register (and other similarly behaving interrupt pending
registers on this device.) The patch below at least stops us creating
new interrupts.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 7840487cd6298f9f931103b558290d8d98d41c49 upstream.
The i2c core driver will turn the platform device ID to busnum
When using platfrom device ID as -1, it means dynamically assigned
the busnum. When writing code, we need to make sure the busnum,
and call i2c_register_board_info(int busnum, ...) to register device
if using -1, we do not know the value of busnum
In order to solve this issue, set the platform device ID as a fix number
Here using 0 to match the busnum used in i2c_regsiter_board_info()
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 3d9a0183dd3423353e9e363bcc261c1220d05f9f upstream.
Newer at91sam9g10 SoC revision can't be detected, so the kernel can't boot with
this kind of kernel panic:
"AT91: Impossible to detect the SOC type"
CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
CPU: VIVT data cache, VIVT instruction cache
Machine: Atmel AT91SAM9G10-EK
Ignoring tag cmdline (using the default kernel command line)
bootconsole [earlycon0] enabled
Memory policy: ECC disabled, Data cache writeback
Kernel panic - not syncing: AT91: Impossible to detect the SOC type
[<c00133d4>] (unwind_backtrace+0x0/0xe0) from [<c02366dc>] (panic+0x78/0x1cc)
[<c02366dc>] (panic+0x78/0x1cc) from [<c02fa35c>] (at91_map_io+0x90/0xc8)
[<c02fa35c>] (at91_map_io+0x90/0xc8) from [<c02f9860>] (paging_init+0x564/0x6d0)
[<c02f9860>] (paging_init+0x564/0x6d0) from [<c02f7914>] (setup_arch+0x464/0x704)
[<c02f7914>] (setup_arch+0x464/0x704) from [<c02f44f8>] (start_kernel+0x6c/0x2d4)
[<c02f44f8>] (start_kernel+0x6c/0x2d4) from [<20008040>] (0x20008040)
The reason for this is that the Debug Unit Chip ID Register has changed between
Engineering Sample and definitive revision of the SoC. Changing the check of
cidr to socid will address the problem. We do not integrate this check to the
list just above because we also have to make sure that the extended id is
disregarded.
Signed-off-by: Ivan Shugov <ivan.shugov@gmail.com>
[nicolas.ferre@atmel.com: change commit message]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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commit 5f40b909728ad784eb43aa309d3c4e9bdf050781 upstream.
When booting a secondary CPU, the primary CPU hands two sets of page
tables via the secondary_data struct:
(1) swapper_pg_dir: a normal, cacheable, shared (if SMP) mapping
of the kernel image (i.e. the tables used by init_mm).
(2) idmap_pgd: an uncached mapping of the .idmap.text ELF
section.
The idmap is generally used when enabling and disabling the MMU, which
includes early CPU boot. In this case, the secondary CPU switches to
swapper as soon as it enters C code:
struct mm_struct *mm = &init_mm;
unsigned int cpu = smp_processor_id();
/*
* All kernel threads share the same mm context; grab a
* reference and switch to it.
*/
atomic_inc(&mm->mm_count);
current->active_mm = mm;
cpumask_set_cpu(cpu, mm_cpumask(mm));
cpu_switch_mm(mm->pgd, mm);
This causes a problem on ARMv7, where the identity mapping is treated as
strongly-ordered leading to architecturally UNPREDICTABLE behaviour of
exclusive accesses, such as those used by atomic_inc.
This patch re-orders the secondary_start_kernel function so that we
switch to swapper before performing any exclusive accesses.
Cc: David McKay <david.mckay@st.com>
Reported-by: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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