ARM: bugs: add support for per-processor bug checking

Commit 9d3a04925deeabb97c8e26d940b501a2873e8af3 upstream.

Add support for per-processor bug checking - each processor function
descriptor gains a function pointer for this check, which must not be
an __init function.  If non-NULL, this will be called whenever a CPU
enters the kernel via which ever path (boot CPU, secondary CPU startup,
CPU resuming, etc.)

This allows processor specific bug checks to validate that workaround
bits are properly enabled by firmware via all entry paths to the kernel.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h
index 8877ad5ffe103f7c411fe3c80d40f048c9bb5777..f379f5f849a926c2a89bb1055f7af52f7a41fc07 100644 (file)
--- a/arch/arm/include/asm/proc-fns.h
+++ b/arch/arm/include/asm/proc-fns.h
@@ -36,6 +36,10 @@ extern struct processor {
         * Set up any processor specifics
         */
        void (*_proc_init)(void);
+       /*
+        * Check for processor bugs
+        */
+       void (*check_bugs)(void);
        /*
         * Disable any processor specifics
         */

diff --git a/arch/arm/kernel/bugs.c b/arch/arm/kernel/bugs.c
index 16e7ba2a9cc40c77f9d39a8e24efc861c7122273..7be5113101915cd81a5558f45238041138fb5a58 100644 (file)
--- a/arch/arm/kernel/bugs.c
+++ b/arch/arm/kernel/bugs.c
@@ -5,6 +5,10 @@
 
 void check_other_bugs(void)
 {
+#ifdef MULTI_CPU
+       if (processor.check_bugs)
+               processor.check_bugs();
+#endif
 }
 
 void __init check_bugs(void)

diff --git a/arch/arm/mm/proc-macros.S b/arch/arm/mm/proc-macros.S
index 0d40c285bd864c87a5e02d59d35d789183334700..7d9176c4a21dc1b309ddca3e6233373b0cc22341 100644 (file)
--- a/arch/arm/mm/proc-macros.S
+++ b/arch/arm/mm/proc-macros.S
@@ -274,13 +274,14 @@
        mcr     p15, 0, ip, c7, c10, 4          @ data write barrier
        .endm
 
-.macro define_processor_functions name:req, dabort:req, pabort:req, nommu=0, suspend=0
+.macro define_processor_functions name:req, dabort:req, pabort:req, nommu=0, suspend=0, bugs=0
        .type   \name\()_processor_functions, #object
        .align 2
 ENTRY(\name\()_processor_functions)
        .word   \dabort
        .word   \pabort
        .word   cpu_\name\()_proc_init
+       .word   \bugs
        .word   cpu_\name\()_proc_fin
        .word   cpu_\name\()_reset
        .word   cpu_\name\()_do_idle