linux/arch/arm/kernel
Russell King 6ebbf2ce43 ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+
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>
2014-07-18 12:29:04 +01:00
..
.gitignore
arch_timer.c arch_timer: Move to generic sched_clock framework 2013-10-09 16:54:10 -07:00
armksyms.c ARM: Better virt_to_page() handling 2014-04-03 22:46:34 +01:00
arthur.c
asm-offsets.c ARM: KVM: introduce per-vcpu HYP Configuration Register 2014-03-03 01:15:23 +00:00
atags.h ARM: constify machine_desc structure uses 2013-07-26 14:55:59 +01:00
atags_compat.c ARM: 7505/1: split out ATAGS parsing 2012-09-03 22:55:56 +01:00
atags_parse.c ARM: 8025/1: Get rid of meminfo 2014-06-01 01:17:12 +01:00
atags_proc.c procfs: new helper - PDE_DATA(inode) 2013-04-09 14:13:32 -04:00
bios32.c ARM/PCI: Call pcie_bus_configure_settings() to set MPS 2014-05-30 10:50:57 -06:00
calls.S ARM: add renameat2 syscall 2014-04-23 11:27:42 +01:00
cpuidle.c cpuidle: Add common time keeping and irq enabling 2012-03-21 01:59:40 -04:00
crash_dump.c ARM: 8012/1: kdump: Avoid overflow when converting pfn to physaddr 2014-04-07 12:10:00 +01:00
debug.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
devtree.c Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next 2014-06-05 15:57:04 -07:00
dma-isa.c
dma.c
early_printk.c early_printk: consolidate random copies of identical code 2013-04-29 18:28:13 -07:00
elf.c Disintegrate asm/system.h for ARM 2012-03-28 18:30:01 +01:00
entry-armv.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
entry-common.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
entry-header.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
entry-v7m.S ARM: 7890/1: v7-M: drop using mach/entry-macro.S 2013-12-29 12:32:32 +00:00
etm.c ARM: 7905/1: etm: Remove unnecessary amba_set_drvdata() 2013-12-29 12:32:34 +00:00
fiq.c ARM: 7819/1: fiq: Cast the first argument of flush_icache_range() 2013-08-20 00:11:50 +01:00
fiqasm.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
ftrace.c ARM: 8022/1: ftrace: work with CONFIG_DEBUG_SET_MODULE_RONX 2014-04-23 01:24:31 +01:00
head-common.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
head-nommu.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
head.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
hibernate.c ARM: 8011/1: ARM hibernation / suspend-to-disk 2014-04-23 01:24:14 +01:00
hw_breakpoint.c CPU hotplug notifiers registration fixes for 3.15-rc1 2014-04-07 14:55:46 -07:00
hyp-stub.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
insn.c ARM: fix missing bug.h include in arch/arm/kernel/insn.c 2012-03-30 11:51:46 +01:00
insn.h ARM: 7334/1: add jump label support 2012-03-24 09:38:56 +00:00
io.c ARM: 7930/1: Introduce atomic MMIO modify 2014-01-28 14:06:25 +00:00
irq.c ARM: l2c: add platform independent core L2 cache OF initialisation 2014-05-30 00:49:00 +01:00
isa.c arm: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:15 -07:00
iwmmxt.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
jump_label.c ARM: 7334/1: add jump label support 2012-03-24 09:38:56 +00:00
kgdb.c
kprobes-arm.c ARM: Make arch_specific_insn a define for new arch_probes_insn structure 2014-03-18 16:39:40 -04:00
kprobes-common.c ARM: probes: fix instruction fetch order with <asm/opcodes.h> 2014-04-01 16:45:19 +03:00
kprobes-test-arm.c ARM: kprobes-test: use <asm/opcodes.h> for ARM instruction building 2014-04-01 16:48:24 +03:00
kprobes-test-thumb.c ARM: kprobes-test: use <asm/opcodes.h> for Thumb instruction building 2014-04-01 16:48:26 +03:00
kprobes-test.c ARM: kprobes-test: Workaround GAS .align bug 2014-04-01 16:48:27 +03:00
kprobes-test.h ARM: kprobes-test: Workaround GAS .align bug 2014-04-01 16:48:27 +03:00
kprobes-thumb.c ARM: probes: fix instruction fetch order with <asm/opcodes.h> 2014-04-01 16:45:19 +03:00
kprobes.c ARM: probes: fix instruction fetch order with <asm/opcodes.h> 2014-04-01 16:45:19 +03:00
kprobes.h ARM: Make arch_specific_insn a define for new arch_probes_insn structure 2014-03-18 16:39:40 -04:00
machine_kexec.c ARM: 8030/1: ARM : kdump : add arch_crash_save_vmcoreinfo 2014-04-22 22:23:58 +01:00
Makefile Merge branches 'alignment', 'fixes', 'l2c' (early part) and 'misc' into for-next 2014-06-05 12:35:52 +01:00
module.c Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2013-11-14 08:51:29 +09:00
opcodes.c ARM: 7206/1: Add generic ARM instruction set condition code checks. 2011-12-13 08:52:02 +00:00
patch.c ARM: 7332/1: extract out code patch function from kprobes 2012-03-24 09:38:55 +00:00
patch.h ARM: 7332/1: extract out code patch function from kprobes 2012-03-24 09:38:55 +00:00
perf_event.c perf/ARM: Use common PMU interrupt disabled code 2014-06-05 12:30:00 +02:00
perf_event_cpu.c ARM: make it easier to check the CPU part number correctly 2014-07-18 12:29:02 +01:00
perf_event_v6.c ARM: perf: don't pretend to support counting of L1I writes 2013-01-16 12:01:59 +00:00
perf_event_v7.c ARM: perf: fix compiler warning with gcc 4.6.4 (and tidy code) 2014-06-19 11:29:39 +01:00
perf_event_xscale.c ARM: perf: don't pretend to support counting of L1I writes 2013-01-16 12:01:59 +00:00
perf_regs.c ARM: perf: add support for perf registers API 2013-09-30 16:41:50 +01:00
pj4-cp0.c ARM: 8040/1: pj4: properly detect existence of iWMMXt coprocessor 2014-04-25 12:07:34 +01:00
probes-arm.c ARM: Make arch_specific_insn a define for new arch_probes_insn structure 2014-03-18 16:39:40 -04:00
probes-arm.h ARM: Make arch_specific_insn a define for new arch_probes_insn structure 2014-03-18 16:39:40 -04:00
probes-thumb.c ARM: Make arch_specific_insn a define for new arch_probes_insn structure 2014-03-18 16:39:40 -04:00
probes-thumb.h ARM: Make arch_specific_insn a define for new arch_probes_insn structure 2014-03-18 16:39:40 -04:00
probes.c ARM: probes: fix instruction fetch order with <asm/opcodes.h> 2014-04-01 16:45:19 +03:00
probes.h ARM: Make arch_specific_insn a define for new arch_probes_insn structure 2014-03-18 16:39:40 -04:00
process.c Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2014-04-11 11:56:40 -07:00
psci.c PSCI: Add initial support for PSCIv0.2 functions 2014-05-15 10:16:00 -04:00
psci_smp.c ARM: Check if a CPU has gone offline 2014-05-15 10:16:30 -04:00
ptrace.c ARM: 8087/1: ptrace: reload syscall number after secure_computing() check 2014-06-29 10:29:35 +01:00
relocate_kernel.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
return_address.c ARM: 7676/1: fix a wrong value returned from CALLER_ADDRn 2013-03-19 11:43:46 +00:00
setup.c Merge branches 'alignment', 'fixes', 'l2c' (early part) and 'misc' into for-next 2014-06-05 12:35:52 +01:00
signal.c ARM: add uprobes support 2014-03-18 16:39:40 -04:00
sigreturn_codes.S ARM: 7895/1: signal: fix armv7-m build issue in sigreturn_codes.S 2013-11-30 22:21:00 +00:00
sleep.S ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ 2014-07-18 12:29:04 +01:00
smp.c cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE} 2014-03-19 14:10:24 +01:00
smp_scu.c ARM: smp_scu: data endian fixes 2013-10-19 20:46:33 +01:00
smp_tlb.c ARM: 7855/1: Add check for Cortex-A15 errata 798181 ECO 2013-10-29 11:06:13 +00:00
smp_twd.c cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE} 2014-03-19 14:10:24 +01:00
stacktrace.c ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation 2014-05-30 01:12:32 +01:00
suspend.c ARM: suspend: use hash of cpu_logical_map value to index into save array 2013-07-30 09:00:43 -04:00
swp_emulate.c arm: single_open() leaks 2013-05-05 00:07:22 -04:00
sys_arm.c arm: switch to generic fork/vfork/clone 2012-11-28 22:13:54 -05:00
sys_oabi-compat.c locks: rename file-private locks to "open file description locks" 2014-04-22 08:23:58 -04:00
tcm.c ARM: add permission annotations to MT_MEMORY* mapping types 2013-12-11 09:53:14 +00:00
thumbee.c ARM: 7385/1: ThumbEE: Use cpuid macros to read ID_PFR0 for ThumbEE 2012-04-25 19:49:26 +01:00
time.c ARM: call of_clk_init from default time_init handler 2013-09-29 21:09:15 +02:00
topology.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-06-12 19:42:15 -07:00
traps.c Dump the registers on undefined instruction userspace faults 2014-04-11 14:48:39 +01:00
unwind.c arm, unwind, LLVMLinux: Enable clang to be used for unwinding the stack 2014-06-07 11:44:39 -07:00
uprobes-arm.c ARM: add uprobes support 2014-03-18 16:39:40 -04:00
uprobes.c ARM: 8043/1: uprobes need icache flush after xol write 2014-05-25 23:48:45 +01:00
uprobes.h ARM: add uprobes support 2014-03-18 16:39:40 -04:00
v7m.c ARM: 7828/1: ARMv7-M: implement restart routine common to all v7-M machines 2013-09-02 13:49:29 +01:00
vmlinux.lds.S ARM: use linker magic for vectors and vector stubs 2013-07-31 21:34:24 +01:00
xscale-cp0.c arm: remove several unnecessary module.h include instances 2011-10-31 19:30:48 -04:00