[PATCH v2] ARM: save/restore diagnostic register on Cortex-A9 suspend/resume
Shawn Guo
shawn.guo at freescale.com
Sun Jun 22 03:15:19 PDT 2014
The CP15 diagnostic register holds ARM errata bits on Cortex-A9, so it
needs to be saved/restored on suspend/resume. Otherwise, the
effectiveness of errata workaround gets lost together with diagnostic
register bit across suspend/resume cycle.
The patch adds a couple of Cortex-A9 specific suspend and resume
functions to handle the diagnostic register across suspend/resume cycle.
Signed-off-by: Shawn Guo <shawn.guo at freescale.com>
---
Changes since v1:
- Add Cortex-A9 specific processor function for suspend and resume
to handle diagnostic register across suspend/resume cycle
arch/arm/include/asm/glue-proc.h | 18 +++++++++---------
arch/arm/mm/proc-v7.S | 31 ++++++++++++++++++++++++++++++-
2 files changed, 39 insertions(+), 10 deletions(-)
diff --git a/arch/arm/include/asm/glue-proc.h b/arch/arm/include/asm/glue-proc.h
index 74a8b84f3cb1..74be7c22035a 100644
--- a/arch/arm/include/asm/glue-proc.h
+++ b/arch/arm/include/asm/glue-proc.h
@@ -221,15 +221,6 @@
# endif
#endif
-#ifdef CONFIG_CPU_V7
-# ifdef CPU_NAME
-# undef MULTI_CPU
-# define MULTI_CPU
-# else
-# define CPU_NAME cpu_v7
-# endif
-#endif
-
#ifdef CONFIG_CPU_V7M
# ifdef CPU_NAME
# undef MULTI_CPU
@@ -248,6 +239,15 @@
# endif
#endif
+#ifdef CONFIG_CPU_V7
+/*
+ * Cortex-A9 needs a different suspend/resume function, so we need
+ * multiple CPU support for ARMv7 anyway.
+ */
+# undef MULTI_CPU
+# define MULTI_CPU
+#endif
+
#ifndef MULTI_CPU
#define cpu_proc_init __glue(CPU_NAME,_proc_init)
#define cpu_proc_fin __glue(CPU_NAME,_proc_fin)
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 3db2c2f04a30..e26bfaa419ee 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -152,6 +152,34 @@ ENTRY(cpu_v7_do_resume)
ENDPROC(cpu_v7_do_resume)
#endif
+/*
+ * Cortex-A9 processor functions
+ */
+ globl_equ cpu_ca9mp_proc_init, cpu_v7_proc_init
+ globl_equ cpu_ca9mp_proc_fin, cpu_v7_proc_fin
+ globl_equ cpu_ca9mp_reset, cpu_v7_reset
+ globl_equ cpu_ca9mp_do_idle, cpu_v7_do_idle
+ globl_equ cpu_ca9mp_dcache_clean_area, cpu_v7_dcache_clean_area
+ globl_equ cpu_ca9mp_switch_mm, cpu_v7_switch_mm
+ globl_equ cpu_ca9mp_set_pte_ext, cpu_v7_set_pte_ext
+.globl cpu_ca9mp_suspend_size
+.equ cpu_ca9mp_suspend_size, cpu_v7_suspend_size + 1 * 4
+#ifdef CONFIG_ARM_CPU_SUSPEND
+ENTRY(cpu_ca9mp_do_suspend)
+ stmfd sp!, {r4}
+ mrc p15, 0, r4, c15, c0, 1 @ Diagnostic register
+ stmia r0!, {r4}
+ ldmfd sp!, {r4}
+ b cpu_v7_do_suspend
+ENDPROC(cpu_ca9mp_do_suspend)
+
+ENTRY(cpu_ca9mp_do_resume)
+ ldmia r0!, {r4}
+ mcr p15, 0, r4, c15, c0, 1 @ Diagnostic register
+ b cpu_v7_do_resume
+ENDPROC(cpu_ca9mp_do_resume)
+#endif
+
#ifdef CONFIG_CPU_PJ4B
globl_equ cpu_pj4b_switch_mm, cpu_v7_switch_mm
globl_equ cpu_pj4b_set_pte_ext, cpu_v7_set_pte_ext
@@ -418,6 +446,7 @@ __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
+ define_processor_functions ca9mp, dabort=v7_early_abort, pabort=v7_pabort, suspend=1
#ifdef CONFIG_CPU_PJ4B
define_processor_functions pj4b, dabort=v7_early_abort, pabort=v7_pabort, suspend=1
#endif
@@ -470,7 +499,7 @@ __v7_ca5mp_proc_info:
__v7_ca9mp_proc_info:
.long 0x410fc090
.long 0xff0ffff0
- __v7_proc __v7_ca9mp_setup
+ __v7_proc __v7_ca9mp_setup, proc_fns = ca9mp_processor_functions
.size __v7_ca9mp_proc_info, . - __v7_ca9mp_proc_info
#endif /* CONFIG_ARM_LPAE */
--
1.8.3.2
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