[PATCH 1/1] perf/arm-cmn: Add more bits to child node address offset field

Ilkka Koskinen ilkka at os.amperecomputing.com
Mon Aug 8 12:54:55 PDT 2022


CMN-600 uses bits [27:0] for child node address offset while bits [30:28]
are required to be zero.

For CMN-650, the child node address offset field has been increased
to include bits [29:0] while leaving only bit 30 set to zero.

Let's include the missing two bits and assume older implementations
comply with the spec and set bits [29:28] to 0.

Signed-off-by: Ilkka Koskinen <ilkka at os.amperecomputing.com>
---

I have tested this patch on CMN-600 and CMN-650.

drivers/perf/arm-cmn.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index 80d8309652a4..b80a9b74662b 100644
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -36,7 +36,7 @@
 #define CMN_CI_CHILD_COUNT		GENMASK_ULL(15, 0)
 #define CMN_CI_CHILD_PTR_OFFSET		GENMASK_ULL(31, 16)
 
-#define CMN_CHILD_NODE_ADDR		GENMASK(27, 0)
+#define CMN_CHILD_NODE_ADDR		GENMASK(29, 0)
 #define CMN_CHILD_NODE_EXTERNAL		BIT(31)
 
 #define CMN_MAX_DIMENSION		12
-- 
2.17.1




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