ARM: l2c: provide generic hook to intercept writes to secure registers

When Linux is running in the non-secure world, any write to a secure
L2C register will generate an abort.  Platforms normally have to call
firmware to work around this.  Provide a hook for them to intercept
any L2C secure register write.

l2c_write_sec() avoids writes to secure registers which are already set
to the appropriate value, thus avoiding the overhead of needlessly
calling into the secure monitor.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/arm/include/asm/outercache.h b/arch/arm/include/asm/outercache.h
index e96f194bf3d4..864afe2114d3 100644
--- a/arch/arm/include/asm/outercache.h
+++ b/arch/arm/include/asm/outercache.h
@@ -32,8 +32,11 @@ struct outer_cache_fns {
 #ifdef CONFIG_OUTER_CACHE_SYNC
 	void (*sync)(void);
 #endif
-	void (*set_debug)(unsigned long);
 	void (*resume)(void);
+
+	/* This is an ARM L2C thing */
+	void (*set_debug)(unsigned long);
+	void (*write_sec)(unsigned long, unsigned);
 };
 
 extern struct outer_cache_fns outer_cache;