[PATCH 4/4] msm: scm: Get cacheline size from CTR

Stephen Boyd sboyd at codeaurora.org
Thu Feb 24 13:44:45 EST 2011


Instead of hardcoding the cacheline size as 32, get the cacheline
size from the CTR register.

Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
---
 arch/arm/mach-msm/scm.c |   17 ++++++++++++-----
 1 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-msm/scm.c b/arch/arm/mach-msm/scm.c
index cfa808d..0528c71 100644
--- a/arch/arm/mach-msm/scm.c
+++ b/arch/arm/mach-msm/scm.c
@@ -26,9 +26,6 @@
 
 #include "scm.h"
 
-/* Cache line size for msm8x60 */
-#define CACHELINESIZE 32
-
 #define SCM_ENOMEM		-5
 #define SCM_EOPNOTSUPP		-4
 #define SCM_EINVAL_ADDR		-3
@@ -207,6 +204,14 @@ static int __scm_call(const struct scm_command *cmd)
 	return ret;
 }
 
+static inline u32 dcache_line_size(void)
+{
+	u32 ctr;
+
+	asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
+	return 4 << ((ctr >> 16) & 0xf);
+}
+
 /**
  * scm_call() - Send an SCM command
  * @svc_id: service identifier
@@ -243,11 +248,13 @@ int scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf, size_t cmd_len,
 	do {
 		u32 start = (u32)rsp;
 		u32 end = (u32)scm_get_response_buffer(rsp) + resp_len;
-		start &= ~(CACHELINESIZE - 1);
+		u32 cacheline_size = dcache_line_size();
+
+		start &= ~(cacheline_size - 1);
 		while (start < end) {
 			asm ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start)
 			     : "memory");
-			start += CACHELINESIZE;
+			start += cacheline_size;
 		}
 	} while (!rsp->is_complete);
 
-- 
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.




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