perf/arm-cmn: Add more bits to child node address offset field

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@os.amperecomputing.com>
Fixes: 60d1504 ("perf/arm-cmn: Support new IP features")
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20220808195455.79277-1-ilkka@os.amperecomputing.com
Signed-off-by: Will Deacon <will@kernel.org>

Author: ilkka-koskinen

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