kernel/arch/arm/mm/proc-mohawk.S, branch linux-4.15.y

ARM: mohawk: allow building with MMU disabled

2015-12-01T20:44:25Z

It is in principle possible to build an MMP kernel for the mohawk CPU with the MMU code disabled, except for one simple build error: proc-mohawk.S:345: Error: invalid operands (*UND* and *UND* sections) for `|' proc-mohawk.S:345: Error: invalid operands (*ABS* and *UND* sections) for `|' proc-mohawk.S:345: Error: invalid operands (*UND* and *UND* sections) for `|' proc-mohawk.S:345: Error: invalid operands (*UND* and *UND* sections) for `|' proc-mohawk.S:345: Error: undefined symbol L_PTE_USER used as an immediate value This patch changes the proc-mohawk code to do the same as the other CPUs and not try to actually do anything for the cpu_mohawk_set_pte_ext function, which won't be used anyway. Signed-off-by: Arnd Bergmann

ARM: 8314/1: replace PROCINFO embedded branch with relative offset

2015-03-28T15:46:14Z

This patch replaces the 'branch to setup()' instructions embedded in the PROCINFO structs with the offset to that setup function relative to the base of the struct. This preserves the position independent nature of that field, but uses a data item rather than an instruction. This is mainly done to prevent linker failures on large kernels, where the setup function is out of reach for the branch. Acked-by: Nicolas Pitre Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King

ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+

2014-07-18T11:29:04Z

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 Tested-by: Stephen Warren # Tegra Jetson TK1 Tested-by: Robert Jarzmik # mioa701_bootresume.S Tested-by: Andrew Lunn # Kirkwood Tested-by: Shawn Guo Tested-by: Tony Lindgren # OMAPs Tested-by: Gregory CLEMENT # Armada XP, 375, 385 Acked-by: Sekhar Nori # DaVinci Acked-by: Christoffer Dall # kvm/hyp Acked-by: Haojian Zhuang # PXA3xx Acked-by: Stefano Stabellini # Xen Tested-by: Uwe Kleine-König # ARMv7M Tested-by: Simon Horman # Shmobile Signed-off-by: Russell King

arm: delete cpuinit/CPUINIT usage from all ARM users

2013-07-14T23:36:52Z

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 Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker

ARM: Do 15e0d9e37c (ARM: pm: let platforms select cpu_suspend support) properly

2013-04-08T11:00:38Z

Let's do the changes properly and fix the same problem everywhere, not just for one case. Cc: # kernels containing 15e0d9e37c or equivalent Signed-off-by: Russell King

ARM: mm: implement LoUIS API for cache maintenance ops

2012-09-25T10:20:25Z

ARM v7 architecture introduced the concept of cache levels and related control registers. New processors like A7 and A15 embed an L2 unified cache controller that becomes part of the cache level hierarchy. Some operations in the kernel like cpu_suspend and __cpu_disable do not require a flush of the entire cache hierarchy to DRAM but just the cache levels belonging to the Level of Unification Inner Shareable (LoUIS), which in most of ARM v7 systems correspond to L1. The current cache flushing API used in cpu_suspend and __cpu_disable, flush_cache_all(), ends up flushing the whole cache hierarchy since for v7 it cleans and invalidates all cache levels up to Level of Coherency (LoC) which cripples system performance when used in hot paths like hotplug and cpuidle. Therefore a new kernel cache maintenance API must be added to cope with latest ARM system requirements. This patch adds flush_cache_louis() to the ARM kernel cache maintenance API. This function cleans and invalidates all data cache levels up to the Level of Unification Inner Shareable (LoUIS) and invalidates the instruction cache for processors that support it (> v7). This patch also creates an alias of the cache LoUIS function to flush_kern_all for all processor versions prior to v7, so that the current cache flushing behaviour is unchanged for those processors. v7 cache maintenance code implements a cache LoUIS function that cleans and invalidates the D-cache up to LoUIS and invalidates the I-cache, according to the new API. Reviewed-by: Santosh Shilimkar Reviewed-by: Nicolas Pitre Signed-off-by: Lorenzo Pieralisi Tested-by: Shawn Guo

Merge tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

2012-05-22T16:41:01Z

Pull arm-soc power management changes from Olof Johansson: "Power management changes here are mostly for the omap platform, but also include cpuidle changes for ux500 and suspend/resume code for mmp." * tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (48 commits) ARM: OMAP2+: WDTIMER integration: fix !PM boot crash, disarm timer after hwmod reset ARM: OMAP2/3: hwmod data: Add 32k-sync timer data to hwmod database ARM: OMAP4: hwmod_data: Name the common irq for McBSP ports ARM: OMAP4: hwmod data: I2C: add flag for context restore ARM: OMAP3: hwmod_data: Rename the common irq for McBSP ports ARM: OMAP2xxx: hwmod data: add HDQ/1-wire hwmod ARM: OMAP3: hwmod data: add HDQ/1-wire hwmod ARM: OMAP2+: hwmod data: add HDQ/1-wire hwmod shared data ARM: OMAP2+: HDQ1W: add custom reset function ARM: OMAP2420: hwmod data: Add MMC hwmod data for 2420 arm: omap3: clockdomain data: Remove superfluous commas from gfx_sgx_3xxx_wkdeps[] ARM: OMAP2+: powerdomain: Get rid off duplicate pwrdm_clkdm_state_switch() API ARM: OMAP3: clock data: add clockdomain for HDQ functional clock ARM: OMAP3+: dpll: Configure autoidle mode only if it's supported ARM: OMAP2+: dmtimer: cleanup iclk usage ARM: OMAP4+: Add prm and cm base init function. ARM: OMAP2/3: Add idle_st bits for ST_32KSYNC timer to prcm-common header ARM: OMAP3: Fix CM register bit masks ARM: OMAP: clock: convert AM3517/3505 detection/flags to AM35xx ARM: OMAP3: clock data: treat all AM35x devices the same ...

ARM: mm: proc-mohawk: add suspend resume for mohawk

2012-05-07T03:42:54Z

When enable ARCH_SUSPEND_POSSIBLE, it need defintion of cpu_mohawk_do_suspend and cpu_mohawk_do_resume Signed-off-by: Chao Xie Signed-off-by: Haojian Zhuang <

ARM: 7408/1: cacheflush: return error to userspace when flushing syscall fails

2012-05-02T10:12:49Z

The cacheflush syscall can fail for two reasons: (1) The arguments are invalid (nonsensical address range or no VMA) (2) The region generates a translation fault on a VIPT or PIPT cache This patch allows do_cache_op to return an error code to userspace in the case of the above. The various coherent_user_range implementations are modified to return 0 in the case of VIVT caches or -EFAULT in the case of an abort on v6/v7 cores. Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon Signed-off-by: Russell King

ARM: proc-*.S: place cpu_reset functions into .idmap.text section

2011-12-06T14:04:14Z

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 Signed-off-by: Will Deacon