arm: Disable outer (L2) cache in kexec
kexec does not disable the outer cache before disabling the inner
caches in cpu_proc_fin(). So L2 is enabled across the kexec jump. When
the new kernel enables chaches again, it randomly crashes.
Disabling L2 before calling cpu_proc_fin() cures the problem.
Disabling L2 requires the following new functions: flush_all(),
inv_all() and disable(). Add them to outer_cache_fns and call them
from the kexec code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
diff --git a/arch/arm/include/asm/outercache.h b/arch/arm/include/asm/outercache.h
index 25f76ba..fc19009 100644
--- a/arch/arm/include/asm/outercache.h
+++ b/arch/arm/include/asm/outercache.h
@@ -25,6 +25,9 @@
void (*inv_range)(unsigned long, unsigned long);
void (*clean_range)(unsigned long, unsigned long);
void (*flush_range)(unsigned long, unsigned long);
+ void (*flush_all)(void);
+ void (*inv_all)(void);
+ void (*disable)(void);
#ifdef CONFIG_OUTER_CACHE_SYNC
void (*sync)(void);
#endif
@@ -50,6 +53,24 @@
outer_cache.flush_range(start, end);
}
+static inline void outer_flush_all(void)
+{
+ if (outer_cache.flush_all)
+ outer_cache.flush_all();
+}
+
+static inline void outer_inv_all(void)
+{
+ if (outer_cache.inv_all)
+ outer_cache.inv_all();
+}
+
+static inline void outer_disable(void)
+{
+ if (outer_cache.disable)
+ outer_cache.disable();
+}
+
#else
static inline void outer_inv_range(unsigned long start, unsigned long end)
@@ -58,6 +79,9 @@
{ }
static inline void outer_flush_range(unsigned long start, unsigned long end)
{ }
+static inline void outer_flush_all(void) { }
+static inline void outer_inv_all(void) { }
+static inline void outer_disable(void) { }
#endif
diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
index 1fc74cb..3a8fd514 100644
--- a/arch/arm/kernel/machine_kexec.c
+++ b/arch/arm/kernel/machine_kexec.c
@@ -78,7 +78,10 @@
local_fiq_disable();
setup_mm_for_reboot(0); /* mode is not used, so just pass 0*/
flush_cache_all();
+ outer_flush_all();
+ outer_disable();
cpu_proc_fin();
+ outer_inv_all();
flush_cache_all();
cpu_reset(reboot_code_buffer_phys);
}