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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-07 14:35:24 (GMT) |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-14 21:28:06 (GMT) |
| commit | a6d746789825e4d7229523eebee233b03ad48c54 (patch) | |
| tree | 6bc62363b1b882d9a156d9012ad1dc19884e0e67 /arch/arm/mm | |
| parent | e5a5de4447471ab1a01585f075400c2be36e2cb6 (diff) | |
| download | linux-a6d746789825e4d7229523eebee233b03ad48c54.tar.xz | |
ARM: proc-v7: avoid errata 430973 workaround for non-Cortex A8 CPUs
Avoid the errata 430973 workaround for non-Cortex A8 CPUs. Having this
workaround enabled introduces an additional branch target buffer flush
into the context switching path, something we wish to avoid. To allow
this errata to be enabled in multiplatform kernels while reducing its
impact, rearrange the Cortex-A8 CPU support to avoid impacting on other
Version 7 CPUs.
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/proc-v7-2level.S | 12 | ||||
| -rw-r--r-- | arch/arm/mm/proc-v7.S | 28 |
2 files changed, 36 insertions, 4 deletions
diff --git a/arch/arm/mm/proc-v7-2level.S b/arch/arm/mm/proc-v7-2level.S index ed448d8..10405b8 100644 --- a/arch/arm/mm/proc-v7-2level.S +++ b/arch/arm/mm/proc-v7-2level.S @@ -37,15 +37,18 @@ * It is assumed that: * - we are not using split page tables */ -ENTRY(cpu_v7_switch_mm) +ENTRY(cpu_ca8_switch_mm) #ifdef CONFIG_MMU mov r2, #0 - mmid r1, r1 @ get mm->context.id - ALT_SMP(orr r0, r0, #TTB_FLAGS_SMP) - ALT_UP(orr r0, r0, #TTB_FLAGS_UP) #ifdef CONFIG_ARM_ERRATA_430973 mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB #endif +#endif +ENTRY(cpu_v7_switch_mm) +#ifdef CONFIG_MMU + mmid r1, r1 @ get mm->context.id + ALT_SMP(orr r0, r0, #TTB_FLAGS_SMP) + ALT_UP(orr r0, r0, #TTB_FLAGS_UP) #ifdef CONFIG_PID_IN_CONTEXTIDR mrc p15, 0, r2, c13, c0, 1 @ read current context ID lsr r2, r2, #8 @ extract the PID @@ -61,6 +64,7 @@ ENTRY(cpu_v7_switch_mm) #endif bx lr ENDPROC(cpu_v7_switch_mm) +ENDPROC(cpu_ca8_switch_mm) /* * cpu_v7_set_pte_ext(ptep, pte) diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 6bdaa4c..3d1054f 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -153,6 +153,21 @@ ENDPROC(cpu_v7_do_resume) #endif /* + * Cortex-A8 + */ + globl_equ cpu_ca8_proc_init, cpu_v7_proc_init + globl_equ cpu_ca8_proc_fin, cpu_v7_proc_fin + globl_equ cpu_ca8_reset, cpu_v7_reset + globl_equ cpu_ca8_do_idle, cpu_v7_do_idle + globl_equ cpu_ca8_dcache_clean_area, cpu_v7_dcache_clean_area + globl_equ cpu_ca8_set_pte_ext, cpu_v7_set_pte_ext + globl_equ cpu_ca8_suspend_size, cpu_v7_suspend_size +#ifdef CONFIG_ARM_CPU_SUSPEND + globl_equ cpu_ca8_do_suspend, cpu_v7_do_suspend + globl_equ cpu_ca8_do_resume, cpu_v7_do_resume +#endif + +/* * Cortex-A9 processor functions */ globl_equ cpu_ca9mp_proc_init, cpu_v7_proc_init @@ -451,7 +466,10 @@ __v7_setup_stack: @ define struct processor (see <asm/proc-fns.h> and proc-macros.S) define_processor_functions v7, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 +#ifndef CONFIG_ARM_LPAE + define_processor_functions ca8, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 define_processor_functions ca9mp, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 +#endif #ifdef CONFIG_CPU_PJ4B define_processor_functions pj4b, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 #endif @@ -507,6 +525,16 @@ __v7_ca9mp_proc_info: __v7_proc __v7_ca9mp_proc_info, __v7_ca9mp_setup, proc_fns = ca9mp_processor_functions .size __v7_ca9mp_proc_info, . - __v7_ca9mp_proc_info + /* + * ARM Ltd. Cortex A8 processor. + */ + .type __v7_ca8_proc_info, #object +__v7_ca8_proc_info: + .long 0x410fc080 + .long 0xff0ffff0 + __v7_proc __v7_ca8_proc_info, __v7_setup, proc_fns = ca8_processor_functions + .size __v7_ca8_proc_info, . - __v7_ca8_proc_info + #endif /* CONFIG_ARM_LPAE */ /* |