path: root/arch/arm/lib
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2014-09-12ARM: 8137/1: fix get_user BE behavior for target variable with size of 8 bytesVictor Kamensky
e38361d 'ARM: 8091/2: add get_user() support for 8 byte types' commit broke V7 BE get_user call when target var size is 64 bit, but '*ptr' size is 32 bit or smaller. e38361d changed type of __r2 from 'register unsigned long' to 'register typeof(x) __r2 asm("r2")' i.e before the change even when target variable size was 64 bit, __r2 was still 32 bit. But after e38361d commit, for target var of 64 bit size, __r2 became 64 bit and now it should occupy 2 registers r2, and r3. The issue in BE case that r3 register is least significant word of __r2 and r2 register is most significant word of __r2. But __get_user_4 still copies result into r2 (most significant word of __r2). Subsequent code copies from __r2 into x, but for situation described it will pick up only garbage from r3 register. Special __get_user_64t_(124) functions are introduced. They are similar to corresponding __get_user_(124) function but result stored in r3 register (lsw in case of 64 bit __r2 in BE image). Those function are used by get_user macro in case of BE and target var size is 64bit. Also changed __get_user_lo8 name into __get_user_32t_8 to get consistent naming accross all cases. Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org> Suggested-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-08-08Merge tag 'soc-for-3.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC platform changes from Olof Johansson: "This is the bulk of new SoC enablement and other platform changes for 3.17: - Samsung S5PV210 has been converted to DT and multiplatform - Clock drivers and bindings for some of the lower-end i.MX 1/2 platforms - Kirkwood, one of the popular Marvell platforms, is folded into the mvebu platform code, removing mach-kirkwood - Hwmod data for TI AM43xx and DRA7 platforms - More additions of Renesas shmobile platform support - Removal of plat-samsung contents that can be removed with S5PV210 being multiplatform/DT-enabled and the other two old platforms being removed New platforms (most with only basic support right now): - Hisilicon X5HD2 settop box chipset is introduced - Mediatek MT6589 (mobile chipset) is introduced - Broadcom BCM7xxx settop box chipset is introduced + as usual a lot other pieces all over the platform code" * tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits) ARM: hisi: remove smp from machine descriptor power: reset: move hisilicon reboot code ARM: dts: Add hix5hd2-dkb dts file. ARM: debug: Rename Hi3716 to HIX5HD2 ARM: hisi: enable hix5hd2 SoC ARM: hisi: add ARCH_HISI MAINTAINERS: add entry for Broadcom ARM STB architecture ARM: brcmstb: select GISB arbiter and interrupt drivers ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs ARM: configs: enable SMP in bcm_defconfig ARM: add SMP support for Broadcom mobile SoCs Documentation: arm: misc updates to Marvell EBU SoC status Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC ARM: mvebu: fix build without platforms selected ARM: mvebu: add cpuidle support for Armada 38x ARM: mvebu: add cpuidle support for Armada 370 cpuidle: mvebu: add Armada 38x support cpuidle: mvebu: add Armada 370 support cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7 ARM: mvebu: export the SCU address ...
2014-07-18ARM: 8091/2: add get_user() support for 8 byte typesDaniel Thompson
Recent contributions, including to DRM and binder, introduce 64-bit values in their interfaces. A common motivation for this is to allow the same ABI for 32- and 64-bit userspaces (and therefore also a shared ABI for 32/64 hybrid userspaces). Anyhow, the developers would like to avoid gotchas like having to use copy_from_user(). This feature is already implemented on x86-32 and the majority of other 32-bit architectures. The current list of get_user_8 hold out architectures are: arm, avr32, blackfin, m32r, metag, microblaze, mn10300, sh. Credit: My name sits rather uneasily at the top of this patch. The v1 and v2 versions of the patch were written by Rob Clark and to produce v4 I mostly copied code from Russell King and H. Peter Anvin. However I have mangled the patch sufficiently that *blame* is rightfully mine even if credit should more widely shared. Changelog: v5: updated to use the ret macro (requested by Russell King) v4: remove an inlined add on big endian systems (spotted by Russell King), used __ARMEB__ rather than BIG_ENDIAN (to match rest of file), cleared r3 on EFAULT during __get_user_8. v3: fix a couple of checkpatch issues v2: pass correct size to check_uaccess, and better handling of narrowing double word read with __get_user_xb() (Russell King's suggestion) v1: original Signed-off-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+Russell King
ARMv6 and greater introduced a new instruction ("bx") which can be used to return from function calls. Recent CPUs perform better when the "bx lr" instruction is used rather than the "mov pc, lr" instruction, and this sequence is strongly recommended to be used by the ARM architecture manual (section A.4.1.1). We provide a new macro "ret" with all its variants for the condition code which will resolve to the appropriate instruction. Rather than doing this piecemeal, and miss some instances, change all the "mov pc" instances to use the new macro, with the exception of the "movs" instruction and the kprobes code. This allows us to detect the "mov pc, lr" case and fix it up - and also gives us the possibility of deploying this for other registers depending on the CPU selection. Reported-by: Will Deacon <will.deacon@arm.com> Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1 Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood Tested-by: Shawn Guo <shawn.guo@freescale.com> Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385 Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-16ARM: choose highest resolution delay timerPeter De Schrijver
In case there are several possible delay timers, choose the one with the highest resolution. This code relies on the fact secondary CPUs have not yet been brought online when register_current_timer_delay() is called. This is ensured by implementing calibration_delay_done(), Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Stephen Warren <swarren@nvidia.com>
2014-02-25ARM: 7990/1: asm: rename logical shift macros push pull into lspush lspullVictor Kamensky
Renames logical shift macros, 'push' and 'pull', defined in arch/arm/include/asm/assembler.h, into 'lspush' and 'lspull'. That eliminates name conflict between 'push' logical shift macro and 'push' instruction mnemonic. That allows assembler.h to be included in .S files that use 'push' instruction. Suggested-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-02-25ARM: 7984/1: prefetch: add prefetchw invocations for barriered atomicsWill Deacon
After a bunch of benchmarking on the interaction between dmb and pldw, it turns out that issuing the pldw *after* the dmb instruction can give modest performance gains (~3% atomic_add_return improvement on a dual A15). This patch adds prefetchw invocations to our barriered atomic operations including cmpxchg, test_and_xxx and futexes. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-12-29ARM: 7877/1: use built-in byte swap functionKim Phillips
Enable the compiler intrinsic for byte swapping on arch ARM. This allows the compiler to detect and be able to optimize out byte swappings, and has a very modest benefit on vmlinux size (Linaro gcc 4.8): text data bss dec hex filename 2840310 123932 61960 3026202 2e2d1a vmlinux-lart #orig 2840152 123932 61960 3026044 2e2c7c vmlinux-lart #builtin-bswap 6473120 314840 5616016 12403976 bd4508 vmlinux-mxs #orig 6472586 314848 5616016 12403450 bd42fa vmlinux-mxs #builtin-bswap 7419872 318372 379556 8117800 7bde28 vmlinux-imx_v6_v7 #orig 7419170 318364 379556 8117090 7bdb62 vmlinux-imx_v6_v7 #builtin-bswap Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-12-29ARM: make kernel oops easier to readRussell King
We don't need the offset for the first function name in each backtrace entry; this needlessly consumes screen space. This is virtually always the first or second instruction in the called function. Also, recognise stmfd instructions which include r10 as a valid stack saving instruction, and when dumping the registers, dump six registers per line rather than five, and fix the wrapping. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-11-30ARM: 7907/1: lib: delay-loop: Add align directive to fix BogoMIPS calculationFabio Estevam
Currently mx53 (CortexA8) running at 1GHz reports: Calibrating delay loop... 663.55 BogoMIPS (lpj=3317760) Tom Evans verified that alignments of 0x0 and 0x8 run the two instructions of __loop_delay in one clock cycle (1 clock/loop), while alignments of 0x4 and 0xc take 3 clocks to run the loop twice. (1.5 clock/loop) The original object code looks like this: 00000010 <__loop_const_udelay>: 10: e3e01000 mvn r1, #0 14: e51f201c ldr r2, [pc, #-28] ; 0 <__loop_udelay-0x8> 18: e5922000 ldr r2, [r2] 1c: e0800921 add r0, r0, r1, lsr #18 20: e1a00720 lsr r0, r0, #14 24: e0822b21 add r2, r2, r1, lsr #22 28: e1a02522 lsr r2, r2, #10 2c: e0000092 mul r0, r2, r0 30: e0800d21 add r0, r0, r1, lsr #26 34: e1b00320 lsrs r0, r0, #6 38: 01a0f00e moveq pc, lr 0000003c <__loop_delay>: 3c: e2500001 subs r0, r0, #1 40: 8afffffe bhi 3c <__loop_delay> 44: e1a0f00e mov pc, lr After adding the 'align 3' directive to __loop_delay (align to 8 bytes): 00000010 <__loop_const_udelay>: 10: e3e01000 mvn r1, #0 14: e51f201c ldr r2, [pc, #-28] ; 0 <__loop_udelay-0x8> 18: e5922000 ldr r2, [r2] 1c: e0800921 add r0, r0, r1, lsr #18 20: e1a00720 lsr r0, r0, #14 24: e0822b21 add r2, r2, r1, lsr #22 28: e1a02522 lsr r2, r2, #10 2c: e0000092 mul r0, r2, r0 30: e0800d21 add r0, r0, r1, lsr #26 34: e1b00320 lsrs r0, r0, #6 38: 01a0f00e moveq pc, lr 3c: e320f000 nop {0} 00000040 <__loop_delay>: 40: e2500001 subs r0, r0, #1 44: 8afffffe bhi 40 <__loop_delay> 48: e1a0f00e mov pc, lr 4c: e320f000 nop {0} , which now reports: Calibrating delay loop... 996.14 BogoMIPS (lpj=4980736) Some more test results: On mx31 (ARM1136) running at 532 MHz, before the patch: Calibrating delay loop... 351.43 BogoMIPS (lpj=1757184) On mx31 (ARM1136) running at 532 MHz after the patch: Calibrating delay loop... 528.79 BogoMIPS (lpj=2643968) Also tested on mx6 (CortexA9) and on mx27 (ARM926), which shows the same BogoMIPS value before and after this patch. Reported-by: Tom Evans <tom_usenet@optusnet.com.au> Suggested-by: Tom Evans <tom_usenet@optusnet.com.au> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-11-20ARM: 7893/1: bitops: only emit .arch_extension mp if CONFIG_SMPWill Deacon
Uwe reported a build failure when targetting a NOMMU platform with my recent prefetch changes: arch/arm/lib/changebit.S: Assembler messages: arch/arm/lib/changebit.S:15: Error: architectural extension `mp' is not allowed for the current base architecture This is due to use of the .arch_extension mp directive immediately prior to an ALT_SMP(...) instruction. Whilst the ALT_SMP macro will expand to nothing if !CONFIG_SMP, gas will still choke on the directive. This patch fixes the issue by only emitting the sequence (including the directive) if CONFIG_SMP=y. Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-11-14Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: "Included in this series are: 1. BE8 (modern big endian) changes for ARM from Ben Dooks 2. big.Little support from Nicolas Pitre and Dave Martin 3. support for LPAE systems with all system memory above 4GB 4. Perf updates from Will Deacon 5. Additional prefetching and other performance improvements from Will. 6. Neon-optimised AES implementation fro Ard. 7. A number of smaller fixes scattered around the place. There is a rather horrid merge conflict in tools/perf - I was never notified of the conflict because it originally occurred between Will's tree and other stuff. Consequently I have a resolution which Will forwarded me, which I'll forward on immediately after sending this mail. The other notable thing is I'm expecting some build breakage in the crypto stuff on ARM only with Ard's AES patches. These were merged into a stable git branch which others had already pulled, so there's little I can do about this. The problem is caused because these patches have a dependency on some code in the crypto git tree - I tried requesting a branch I can pull to resolve these, and all I got each time from the crypto people was "we'll revert our patches then" which would only make things worse since I still don't have the dependent patches. I've no idea what's going on there or how to resolve that, and since I can't split these patches from the rest of this pull request, I'm rather stuck with pushing this as-is or reverting Ard's patches. Since it should "come out in the wash" I've left them in - the only build problems they seem to cause at the moment are with randconfigs, and since it's a new feature anyway. However, if by -rc1 the dependencies aren't in, I think it'd be best to revert Ard's patches" I resolved the perf conflict roughly as per the patch sent by Russell, but there may be some differences. Any errors are likely mine. Let's see how the crypto issues work out.. * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (110 commits) ARM: 7868/1: arm/arm64: remove atomic_clear_mask() in "include/asm/atomic.h" ARM: 7867/1: include: asm: use 'int' instead of 'unsigned long' for 'oldval' in atomic_cmpxchg(). ARM: 7866/1: include: asm: use 'long long' instead of 'u64' within atomic.h ARM: 7871/1: amba: Extend number of IRQS ARM: 7887/1: Don't smp_cross_call() on UP devices in arch_irq_work_raise() ARM: 7872/1: Support arch_irq_work_raise() via self IPIs ARM: 7880/1: Clear the IT state independent of the Thumb-2 mode ARM: 7878/1: nommu: Implement dummy early_paging_init() ARM: 7876/1: clear Thumb-2 IT state on exception handling ARM: 7874/2: bL_switcher: Remove cpu_hotplug_driver_{lock,unlock}() ARM: footbridge: fix build warnings for netwinder ARM: 7873/1: vfp: clear vfp_current_hw_state for dying cpu ARM: fix misplaced arch_virt_to_idmap() ARM: 7848/1: mcpm: Implement cpu_kill() to synchronise on powerdown ARM: 7847/1: mcpm: Factor out logical-to-physical CPU translation ARM: 7869/1: remove unused XSCALE_PMU Kconfig param ARM: 7864/1: Handle 64-bit memory in case of 32-bit phys_addr_t ARM: 7863/1: Let arm_add_memory() always use 64-bit arguments ARM: 7862/1: pcpu: replace __get_cpu_var_uses ARM: 7861/1: cacheflush: consolidate single-CPU ARMv7 cache disabling code ...
2013-11-12Merge branch 'devel-stable' into for-nextRussell King
Conflicts: arch/arm/include/asm/atomic.h arch/arm/include/asm/hardirq.h arch/arm/kernel/smp.c
2013-10-29ARM: 7858/1: mm: make UACCESS_WITH_MEMCPY huge page awareSteven Capper
The memory pinning code in uaccess_with_memcpy.c does not check for HugeTLB or THP pmds, and will enter an infinite loop should a __copy_to_user or __clear_user occur against a huge page. This patch adds detection code for huge pages to pin_page_for_write. As this code can be executed in a fast path it refers to the actual pmds rather than the vma. If a HugeTLB or THP is found (they have the same pmd representation on ARM), the page table spinlock is taken to prevent modification whilst the page is pinned. On ARM, huge pages are only represented as pmds, thus no huge pud checks are performed. (For huge puds one would lock the page table in a similar manner as in the pmd case). Two helper functions are introduced; pmd_thp_or_huge will check whether or not a page is huge or transparent huge (which have the same pmd layout on ARM), and pmd_hugewillfault will detect whether or not a page fault will occur on write to the page. Running the following test (with the chunking from read_zero removed): $ dd if=/dev/zero of=/dev/null bs=10M count=1024 Gave: 2.3 GB/s backed by normal pages, 2.9 GB/s backed by huge pages, 5.1 GB/s backed by huge pages, with page mask=HPAGE_MASK. After some discussion, it was decided not to adopt the HPAGE_MASK, as this would have a significant detrimental effect on the overall system latency due to page_table_lock being held for too long. This could be revisited if split huge page locks are adopted. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-09-30ARM: bitops: prefetch the destination word for write prior to strexWill Deacon
The cost of changing a cacheline from shared to exclusive state can be significant, especially when this is triggered by an exclusive store, since it may result in having to retry the transaction. This patch prefixes our atomic bitops implementation with prefetchw, to try and grab the line in exclusive state from the start. The testop macro is left alone, since the barrier semantics limit the usefulness of prefetching data. Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2013-09-17ARM: delete mach-sharkLinus Walleij
The Shark machine sub-architecture (also known as DNARD, the DIGITAL Network Appliance Reference Design) lacks a maintainer able to apply and test patches to modernize the architecture. It is suspected that the current kernel, while it compiles, does not even boot on this machine. The listed maintainer has expressed that he will not be able to spend any time on the maintenance for the coming year. So let's delete it from the kernel for now. It can always be resurrected with git revert if maintenance is resumed. As the VIA82c505 PCI adapter was only used by this architecture, that gets deleted too. Cc: arm@kernel.org Cc: Alexander Schulz <alex@shark-linux.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-09-09ARM: 7835/2: fix modular build of xor_blocks() with NEON enabledArd Biesheuvel
Commit 0195659 introduced a NEON accelerated version of the xor_blocks() function, but it needs the changes in this patch to allow it to be built as a module rather than statically into the kernel. This patch creates a separate module xor-neon.ko which exports the NEON inner xor_blocks() functions depended upon by the regular xor.ko if it is built with CONFIG_KERNEL_MODE_NEON=y Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-07-22Pull branch 'for-rmk' of git://git.linaro.org/people/ardbiesheuvel/linux-arm ↵Russell King
into devel-stable Comments from Ard Biesheuvel: I have included two use cases that I have been using, XOR and RAID-6 checksumming. The former gets a 60% performance boost on the NEON, the latter over 400%. ARM: add support for kernel mode NEON Adds kernel_neon_begin/end (renamed from kernel_vfp_begin/end in the previous version to de-emphasize the VFP part as VFP code that needs software assistance is not supported currently.) Introduces <asm/neon.h> and the Kconfig symbol KERNEL_MODE_NEON. This has been aligned with Catalin for arm64, so any NEON code that does not use assembly but intrinsics or the GCC vectorizer (such as my examples) can potentially be shared between arm and arm64 archs. ARM: move VFP init to an earlier boot stage This is needed so the NEON is enabled when the XOR and RAID-6 algo boot time benchmarks are run. ARM: be strict about FP exceptions in kernel mode This adds a check to vfp_support_entry() to flag unsupported uses of the NEON/VFP in kernel mode. FP exceptions (bounces) are flagged as a bug, this is because of their potentially intermittent nature. Exceptions caused by the fact that kernel_neon_begin has not been called are just routed through the undef handler. ARM: crypto: add NEON accelerated XOR implementation This is the xor_blocks() implementation built with -ftree-vectorize, 60% faster than optimized ARM code. It calls in_interrupt() to check whether the NEON flavor can be used: this should really not be necessary, but due to xor_blocks'squite generic nature, there is no telling how exactly people may be using it in the real world. lib/raid6: add ARM-NEON accelerated syndrome calculation This is a port of the RAID-6 checksumming code in altivec.uc ported to use NEON intrinsics. It is about 4x faster than the sequential code.
2013-07-14arm: delete __cpuinit/__CPUINIT usage from all ARM usersPaul Gortmaker
The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the ARM uses of the __cpuinit macros from C code, and all __CPUINIT from assembly code. It also had two ".previous" section statements that were paired off against __CPUINIT (aka .section ".cpuinit.text") that also get removed here. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-08ARM: crypto: add NEON accelerated XOR implementationArd Biesheuvel
Add a source file xor-neon.c (which is really just the reference C implementation passed through the GCC vectorizer) and hook it up to the XOR framework. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2013-04-03ARM: 7685/1: delay: use private ticks_per_jiffy field for timer-based delay opsWill Deacon
Commit 70264367a243 ("ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock") fixed a problem with our timer-based delay loop, where loops_per_jiffy is scaled by cpufreq yet used directly by the timer delay ops. This patch fixes the problem in a more elegant way by keeping a private ticks_per_jiffy field in the delay ops, independent of loops_per_jiffy and therefore not subject to scaling. The loop-based delay continues to use loops_per_jiffy directly, as it should. Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-03-12ARM: 7670/1: fix the memset fixNicolas Pitre
Commit 455bd4c430b0 ("ARM: 7668/1: fix memset-related crashes caused by recent GCC (4.7.2) optimizations") attempted to fix a compliance issue with the memset return value. However the memset itself became broken by that patch for misaligned pointers. This fixes the above by branching over the entry code from the misaligned fixup code to avoid reloading the original pointer. Also, because the function entry alignment is wrong in the Thumb mode compilation, that fixup code is moved to the end. While at it, the entry instructions are slightly reworked to help dual issue pipelines. Signed-off-by: Nicolas Pitre <nico@linaro.org> Tested-by: Alexander Holler <holler@ahsoftware.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-03-07ARM: 7668/1: fix memset-related crashes caused by recent GCC (4.7.2) ↵Ivan Djelic
optimizations Recent GCC versions (e.g. GCC-4.7.2) perform optimizations based on assumptions about the implementation of memset and similar functions. The current ARM optimized memset code does not return the value of its first argument, as is usually expected from standard implementations. For instance in the following function: void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter) { memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter)); waiter->magic = waiter; INIT_LIST_HEAD(&waiter->list); } compiled as: 800554d0 <debug_mutex_lock_common>: 800554d0: e92d4008 push {r3, lr} 800554d4: e1a00001 mov r0, r1 800554d8: e3a02010 mov r2, #16 ; 0x10 800554dc: e3a01011 mov r1, #17 ; 0x11 800554e0: eb04426e bl 80165ea0 <memset> 800554e4: e1a03000 mov r3, r0 800554e8: e583000c str r0, [r3, #12] 800554ec: e5830000 str r0, [r3] 800554f0: e5830004 str r0, [r3, #4] 800554f4: e8bd8008 pop {r3, pc} GCC assumes memset returns the value of pointer 'waiter' in register r0; causing register/memory corruptions. This patch fixes the return value of the assembly version of memset. It adds a 'mov' instruction and merges an additional load+store into existing load/store instructions. For ease of review, here is a breakdown of the patch into 4 simple steps: Step 1 ====== Perform the following substitutions: ip -> r8, then r0 -> ip, and insert 'mov ip, r0' as the first statement of the function. At this point, we have a memset() implementation returning the proper result, but corrupting r8 on some paths (the ones that were using ip). Step 2 ====== Make sure r8 is saved and restored when (! CALGN(1)+0) == 1: save r8: - str lr, [sp, #-4]! + stmfd sp!, {r8, lr} and restore r8 on both exit paths: - ldmeqfd sp!, {pc} @ Now <64 bytes to go. + ldmeqfd sp!, {r8, pc} @ Now <64 bytes to go. (...) tst r2, #16 stmneia ip!, {r1, r3, r8, lr} - ldr lr, [sp], #4 + ldmfd sp!, {r8, lr} Step 3 ====== Make sure r8 is saved and restored when (! CALGN(1)+0) == 0: save r8: - stmfd sp!, {r4-r7, lr} + stmfd sp!, {r4-r8, lr} and restore r8 on both exit paths: bgt 3b - ldmeqfd sp!, {r4-r7, pc} + ldmeqfd sp!, {r4-r8, pc} (...) tst r2, #16 stmneia ip!, {r4-r7} - ldmfd sp!, {r4-r7, lr} + ldmfd sp!, {r4-r8, lr} Step 4 ====== Rewrite register list "r4-r7, r8" as "r4-r8". Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-02-21ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clockNicolas Pitre
When udelay() is implemented using an architected timer, it is wrong to scale loops_per_jiffy when changing the CPU clock frequency since the timer clock remains constant. The lpj should probably become an implementation detail relevant to the CPU loop based delay routine only and more confined to it. In the mean time this is the minimal fix needed to have expected delays with the timer based implementation when cpufreq is also in use. Reported-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Nicolas Pitre <nico@linaro.org> Tested-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Liviu Dudau <Liviu.Dudau@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-09ARM: export default read_current_timerArnd Bergmann
read_current_timer is used by get_cycles since "ARM: 7538/1: delay: add registration mechanism for delay timer sources", and get_cycles can be used by device drivers in loadable modules, so it has to be exported. Without this patch, building imote2_defconfig fails with ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined! Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Jonathan Austin <jonathan.austin@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-04Merge branch 'arch-timers' into for-linusRussell King
Conflicts: arch/arm/include/asm/timex.h arch/arm/lib/delay.c
2012-09-26ARM: 7538/1: delay: add registration mechanism for delay timer sourcesJonathan Austin
The current timer-based delay loop relies on the architected timer to initiate the switch away from the polling-based implementation. This is unfortunate for platforms without the architected timers but with a suitable delay source (that is, constant frequency, always powered-up and ticking as long as the CPUs are online). This patch introduces a registration mechanism for the delay timer (which provides an unconditional read_current_timer implementation) and updates the architected timer code to use the new interface. Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Jonathan Austin <jonathan.austin@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-09-09ARM: 7529/1: delay: set loops_per_jiffy when moving to timer-based loopWill Deacon
The delay functions may be called by some platforms between switching to the timer-based delay loop but before calibration. In this case, the initial loops_per_jiffy may not be suitable for the timer (although a compromise may be achievable) and delay times may be considered too inaccurate. This patch updates loops_per_jiffy when switching to the timer-based delay loop so that delays are consistent prior to calibration. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-09-09ARM: 7527/1: uaccess: explicitly check __user pointer when !CPU_USE_DOMAINSRussell King
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> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-13ARM: Bring back ARMv3 IO and user access codeRussell King
This partially reverts 357c9c1f07d4546bc3fbc0fd1044d96b114d14ed (ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs). Although we only support StrongARM on the RiscPC, we need to keep the ARMv3 user access code for this platform because the bus does not understand half-word load/stores. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-30arch: remove direct definitions of KERN_<LEVEL> usesJoe Perches
Add #include <linux/kern_levels.h> so that the #define KERN_<LEVEL> macros don't have to be duplicated. Signed-off-by: Joe Perches <joe@perches.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Kay Sievers <kay@vrfy.org> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-27Merge branches 'audit', 'delay', 'fixes', 'misc' and 'sta2x11' into for-linusRussell King
2012-07-09ARM: 7452/1: delay: allow timer-based delay implementation to be selectedWill Deacon
This patch allows a timer-based delay implementation to be selected by switching the delay routines over to use get_cycles, which is implemented in terms of read_current_timer. This further allows us to skip the loop calibration and have a consistent delay function in the face of core frequency scaling. To avoid the pain of dealing with memory-mapped counters, this implementation uses the co-processor interface to the architected timers when they are available. The previous loop-based implementation is kept around for CPUs without the architected timers and we retain both the maximum delay (2ms) and the corresponding conversion factors for determining the number of loops required for a given interval. Since the indirection of the timer routines will only work when called from C, the sa1100 sleep routines are modified to branch to the loop-based delay functions directly. Tested-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-07-09ARM: 7449/1: use generic strnlen_user and strncpy_from_user functionsWill Deacon
This patch implements the word-at-a-time interface for ARM using the same algorithm as x86. We use the fls macro from ARMv5 onwards, where we have a clz instruction available which saves us a mov instruction when targetting Thumb-2. For older CPUs, we use the magic 0x0ff0001 constant. Big-endian configurations make use of the implementation from asm-generic. With this implemented, we can replace our byte-at-a-time strnlen_user and strncpy_from_user functions with the optimised generic versions. Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-05-05ARM: Remove support for ARMv3 ARM610 and ARM710 CPUsRussell King
This patch removes support for ARMv3 CPUs, which haven't worked properly for quite some time (see the FIXME comment in arch/arm/mm/fault.c). The only V3 parts left is the cache model for ARMv3, which is needed for some odd reason by ARM740T CPUs, and being able to build with -march=armv3, which is required for the RiscPC platform due to its bus structure. Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-01-25ARM: 7301/1: Rename the T() macro to TUSER() to avoid namespace conflictsCatalin Marinas
This macro is used to generate unprivileged accesses (LDRT/STRT) to user space. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-12ARM: lib: add call_with_stack function for safely changing stackWill Deacon
When disabling the MMU, it is necessary to take out a 1:1 identity map of the reset code so that it can safely be executed with and without the MMU active. To avoid the situation where the physical address of the reset code aliases with the virtual address of the active stack (which cannot be included in the 1:1 mapping), it is desirable to change to a new stack at a location which is less likely to alias. This code adds a new lib function, call_with_stack: void call_with_stack(void (*fn)(void *), void *arg, void *sp); which changes the stack to point at the sp parameter, before invoking fn(arg) with the new stack selected. Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-11-26ARM: 7171/1: unwind: add unwind directives to bitops assembly macrosWill Deacon
The bitops functions (e.g. _test_and_set_bit) on ARM do not have unwind annotations and therefore the kernel cannot backtrace out of them on a fatal error (for example, NULL pointer dereference). This patch annotates the bitops assembly macros with UNWIND annotations so that we can produce a meaningful backtrace on error. Callers of the macros are modified to pass their function name as a macro parameter, enforcing that the macros are used as standalone function implementations. Acked-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-25Merge branch 'misc' into for-linusRussell King
Conflicts: arch/arm/mach-integrator/integrator_ap.c
2011-10-17ARM: 7125/1: Add unwinding annotations for 64bit division functionsLaura Abbott
The 64bit division functions never had unwinding annotations added. This prevents a backtrace from being printed within the function and if a division by 0 occurs. Add the annotations. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17ARM: 7068/1: process: change from __backtrace to dump_stack in show_regsLaura Abbott
Currently, show_regs calls __backtrace which does nothing if CONFIG_FRAME_POINTER is not set. Switch to dump_stack which handles both CONFIG_FRAME_POINTER and CONFIG_ARM_UNWIND correctly. __backtrace is now superseded by dump_stack in general and show_regs was the last caller so remove __backtrace as well. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-02ARM: include linux/highmem.h in uaccess functionsArnd Bergmann
When highpte support is enabled, this is required to build the kernel. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2011-08-07arm: remove "optimized" SHA1 routinesLinus Torvalds
Since commit 1eb19a12bd22 ("lib/sha1: use the git implementation of SHA-1"), the ARM SHA1 routines no longer work. The reason? They depended on the larger 320-byte workspace, and now the sha1 workspace is just 16 words (64 bytes). So the assembly version would overwrite the stack randomly. The optimized asm version is also probably slower than the new improved C version, so there's no reason to keep it around. At least that was the case in git, where what appears to be the same assembly language version was removed two years ago because the optimized C BLK_SHA1 code was faster. Reported-and-tested-by: Joachim Eastwood <manabian@gmail.com> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-12ARM: remove unnecessary mach/hardware.h includesRob Herring
Remove some includes of mach/hardware.h which are not needed. hardware.h will be removed completely for tegra and cns3xxx in follow on patch. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
2011-05-27ARM: 6945/1: Add unwinding support for division functionsLaura Abbott
The software division functions never had unwinding annotations added. Currently, when a division by zero occurs the backtrace shown will stop at Ldiv0 or some completely unrelated function. Add unwinding annotations in hopes of getting a more useful backtrace when a division by zero occurs. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-03-20Merge branches 'fixes', 'pgt-next' and 'versatile' into develRussell King
2011-02-21ARM: pgtable: add pud-level codeRussell King
Add pud_offset() et.al. between the pgd and pmd code in preparation of using pgtable-nopud.h rather than 4level-fixup.h. This incorporates a fix from Jamie Iles <jamie@jamieiles.com> for uaccess_with_memcpy.c. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-19ARM: 6653/1: bitops: Use BX instead of MOV PC,LRDave Martin
The kernel doesn't officially need to interwork, but using BX wherever appropriate will help educate people into good assembler coding habits. BX is appropriate here because this code is predicated on __LINUX_ARM_ARCH__ >= 6 Signed-off-by: Dave Martin <dave.martin@linaro.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-02ARM: bitops: switch set/clear/change bitops to use ldrex/strexRussell King
Switch the set/clear/change bitops to use the word-based exclusive operations, which are only present in a wider range of ARM architectures than the byte-based exclusive operations. Tested record: - Nicolas Pitre: ext3,rw,le - Sourav Poddar: nfs,le - Will Deacon: ext3,rw,le - Tony Lindgren: ext3+nfs,le Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Sourav Poddar <sourav.poddar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-02ARM: bitops: ensure set/clear/change bitops take a word-aligned pointerRussell King
Add additional instructions to our assembly bitops functions to ensure that they only operate on word-aligned pointers. This will be necessary when we switch these operations to use the word-based exclusive operations. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>