diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-06-30 16:29:12 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-07-18 12:29:04 +0100 |
| commit | 6ebbf2ce437b33022d30badd49dc94d33ecfa498 (patch) | |
| tree | bc015e35b456a28bb0e501803a454dc0c0d3291a /arch/arm/mach-tegra/sleep-tegra30.S | |
| parent | af040ffc9ba1e079ee4c0748aff64fa3d4716fa5 (diff) | |
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>
Diffstat (limited to 'arch/arm/mach-tegra/sleep-tegra30.S')
| -rw-r--r-- | arch/arm/mach-tegra/sleep-tegra30.S | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/arch/arm/mach-tegra/sleep-tegra30.S b/arch/arm/mach-tegra/sleep-tegra30.S index b16d4a57fa59..09cad9b071de 100644 --- a/arch/arm/mach-tegra/sleep-tegra30.S +++ b/arch/arm/mach-tegra/sleep-tegra30.S @@ -142,7 +142,7 @@ ENTRY(tegra30_hotplug_shutdown) /* Powergate this CPU */ mov r0, #TEGRA30_POWER_HOTPLUG_SHUTDOWN bl tegra30_cpu_shutdown - mov pc, lr @ should never get here + ret lr @ should never get here ENDPROC(tegra30_hotplug_shutdown) /* @@ -161,7 +161,7 @@ ENTRY(tegra30_cpu_shutdown) bne _no_cpu0_chk @ It's not Tegra30 cmp r3, #0 - moveq pc, lr @ Must never be called for CPU 0 + reteq lr @ Must never be called for CPU 0 _no_cpu0_chk: ldr r12, =TEGRA_FLOW_CTRL_VIRT @@ -266,7 +266,7 @@ ENTRY(tegra30_sleep_core_finish) mov32 r1, TEGRA_IRAM_LPx_RESUME_AREA add r0, r0, r1 - mov pc, r3 + ret r3 ENDPROC(tegra30_sleep_core_finish) /* @@ -285,7 +285,7 @@ ENTRY(tegra30_sleep_cpu_secondary_finish) mov r0, #0 @ power mode flags (!hotplug) bl tegra30_cpu_shutdown mov r0, #1 @ never return here - mov pc, r7 + ret r7 ENDPROC(tegra30_sleep_cpu_secondary_finish) /* @@ -529,7 +529,7 @@ __no_dual_emc_chanl: mov32 r0, TEGRA_PMC_BASE ldr r0, [r0, #PMC_SCRATCH41] - mov pc, r0 @ jump to tegra_resume + ret r0 @ jump to tegra_resume ENDPROC(tegra30_lp1_reset) .align L1_CACHE_SHIFT @@ -659,7 +659,7 @@ _no_pll_in_iddq: mov r0, #0 /* brust policy = 32KHz */ str r0, [r5, #CLK_RESET_SCLK_BURST] - mov pc, lr + ret lr /* * tegra30_enter_sleep @@ -819,7 +819,7 @@ pmc_io_dpd_skip: dsb - mov pc, lr + ret lr .ltorg /* dummy symbol for end of IRAM */ |