[PATCHv2 4/4] msm: scm: Get cacheline size from CTR
Stephen Boyd
sboyd at codeaurora.org
Mon Mar 21 14:33:50 EDT 2011
Instead of hardcoding the cacheline size as 32, get the cacheline
size from the CTR register. Use an early_initcall because
scm_call() is used to boot the secondary CPUs.
Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
---
Changes since v1:
* Use an early_initcall to get cacheline size (tglx)
* Pull the end assignment out of the for loop
arch/arm/mach-msm/scm.c | 26 ++++++++++++++++++++------
1 files changed, 20 insertions(+), 6 deletions(-)
diff --git a/arch/arm/mach-msm/scm.c b/arch/arm/mach-msm/scm.c
index cfa808d..3103f3a 100644
--- a/arch/arm/mach-msm/scm.c
+++ b/arch/arm/mach-msm/scm.c
@@ -21,14 +21,12 @@
#include <linux/mutex.h>
#include <linux/errno.h>
#include <linux/err.h>
+#include <linux/init.h>
#include <asm/cacheflush.h>
#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 +205,8 @@ static int __scm_call(const struct scm_command *cmd)
return ret;
}
+static u32 cacheline_size;
+
/**
* scm_call() - Send an SCM command
* @svc_id: service identifier
@@ -224,6 +224,7 @@ int scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf, size_t cmd_len,
int ret;
struct scm_command *cmd;
struct scm_response *rsp;
+ u32 end;
cmd = alloc_scm_command(cmd_len, resp_len);
if (!cmd)
@@ -240,14 +241,16 @@ int scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf, size_t cmd_len,
goto out;
rsp = scm_command_to_response(cmd);
+ end = (u32)scm_get_response_buffer(rsp) + resp_len;
+
do {
u32 start = (u32)rsp;
- u32 end = (u32)scm_get_response_buffer(rsp) + resp_len;
- start &= ~(CACHELINESIZE - 1);
+ 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);
@@ -291,3 +294,14 @@ u32 scm_get_version(void)
return version;
}
EXPORT_SYMBOL(scm_get_version);
+
+static int __init scm_init(void)
+{
+ u32 ctr;
+
+ asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
+ cacheline_size = 4 << ((ctr >> 16) & 0xf);
+
+ return 0;
+}
+early_initcall(scm_init);
--
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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