kernel/linux.git/arch/arm/lib/delay.c, branch v6.12.80

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333

2019-06-05T15:37:06+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 136 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Alexios Zavras Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de Signed-off-by: Greg Kroah-Hartman

Revert "arm: move exports to definitions"

2016-11-23T10:00:03+00:00

This reverts commit 4dd1837d7589f468ed109556513f476e7a7f9121. Moving the exports for assembly code into the assembly files breaks KSYM trimming, but also breaks modversions. While fixing the KSYM trimming is trivial, fixing modversions brings us to a technically worse position that we had prior to the above change: - We end up with the prototype definitions divorsed from everything else, which means that adding or removing assembly level ksyms become more fragile: * if adding a new assembly ksyms export, a missed prototype in asm-prototypes.h results in a successful build if no module in the selected configuration makes use of the symbol. * when removing a ksyms export, asm-prototypes.h will get forgotten, with armksyms.c, you'll get a build error if you forget to touch the file. - We end up with the same amount of include files and prototypes, they're just in a header file instead of a .c file with their exports. As for lines of code, we don't get much of a size reduction: (original commit) 47 files changed, 131 insertions(+), 208 deletions(-) (fix for ksyms trimming) 7 files changed, 18 insertions(+), 5 deletions(-) (two fixes for modversions) 1 file changed, 34 insertions(+) 3 files changed, 7 insertions(+), 2 deletions(-) which results in a net total of only 25 lines deleted. As there does not seem to be much benefit from this change of approach, revert the change. Signed-off-by: Russell King

Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild

2016-10-14T21:26:58+00:00

Pull kbuild updates from Michal Marek: - EXPORT_SYMBOL for asm source by Al Viro. This does bring a regression, because genksyms no longer generates checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is working on a patch to fix this. Plus, we are talking about functions like strcpy(), which rarely change prototypes. - Fixes for PPC fallout of the above by Stephen Rothwell and Nick Piggin - fixdep speedup by Alexey Dobriyan. - preparatory work by Nick Piggin to allow architectures to build with -ffunction-sections, -fdata-sections and --gc-sections - CONFIG_THIN_ARCHIVES support by Stephen Rothwell - fix for filenames with colons in the initramfs source by me. * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits) initramfs: Escape colons in depfile ppc: there is no clear_pages to export powerpc/64: whitelist unresolved modversions CRCs kbuild: -ffunction-sections fix for archs with conflicting sections kbuild: add arch specific post-link Makefile kbuild: allow archs to select link dead code/data elimination kbuild: allow architectures to use thin archives instead of ld -r kbuild: Regenerate genksyms lexer kbuild: genksyms fix for typeof handling fixdep: faster CONFIG_ search ia64: move exports to definitions sparc32: debride memcpy.S a bit [sparc] unify 32bit and 64bit string.h sparc: move exports to definitions ppc: move exports to definitions arm: move exports to definitions s390: move exports to definitions m68k: move exports to definitions alpha: move exports to actual definitions x86: move exports to actual definitions ...

ARM: 8595/2: apply more __ro_after_init

2016-08-12T15:47:06+00:00

Guided by grsecurity's analogous __read_only markings in arch/arm, this applies several uses of __ro_after_init to structures that are only updated during __init. Signed-off-by: Kees Cook Signed-off-by: Russell King

arm: move exports to definitions

2016-08-08T03:47:21+00:00

Signed-off-by: Al Viro

ARM: ensure delay timer has sufficient accuracy for delays

2015-04-14T21:28:07+00:00

We have recently had an example of someone wanting to use a 90kHz timer for the software delay loop. udelay() needs to have at least microsecond resolution to allow drivers access to a delay mechanism with a reasonable chance of delaying the period they requested within at least a 50% marging of error, especially for small delays. Discussion about the udelay() accuracy can be found at: https://lkml.org/lkml/2011/1/9/37 Reject timers which are unable to supply this level of resolution. Acked-by: Nicolas Pitre Signed-off-by: Russell King

ARM: choose highest resolution delay timer

2014-06-16T18:48:07+00:00

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 Acked-by: Russell King Signed-off-by: Stephen Warren

arm: delete cpuinit/CPUINIT usage from all ARM users

2013-07-14T23:36:52+00:00

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: 7685/1: delay: use private ticks_per_jiffy field for timer-based delay ops

2013-04-03T15:45:50+00:00

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 Signed-off-by: Will Deacon Signed-off-by: Russell King

ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock

2013-02-21T13:25:36+00:00

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 Signed-off-by: Nicolas Pitre Tested-by: Viresh Kumar Acked-by: Liviu Dudau Cc: stable@vger.kernel.org Signed-off-by: Russell King