perf/arm-cmn: Decode CAL devices properly in debugfs
authorRobin Murphy <robin.murphy@arm.com>
Wed, 11 May 2022 13:12:53 +0000 (14:12 +0100)
committerWill Deacon <will@kernel.org>
Thu, 12 May 2022 12:44:56 +0000 (13:44 +0100)
The debugfs code is lazy, and since it only keeps the bottom byte of
each connect_info register to save space, it also treats the whole thing
as the device_type since the other bits were reserved anyway. Upon
closer inspection, though, this is no longer true on newer IP versions,
so let's be good and decode the exact field properly. This should help
it not get confused when a Component Aggregation Layer is present (which
is already implied if Node IDs are found for both device addresses
represented by the next two lines of the table).

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/6a13a6128a28cfe2eec6d09cf372a167ec9c3b65.1652274773.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
drivers/perf/arm-cmn.c

index a8421a4..80d8309 100644 (file)
@@ -63,6 +63,7 @@
 #define CMN_MXP__CONNECT_INFO_P3       0x0030
 #define CMN_MXP__CONNECT_INFO_P4       0x0038
 #define CMN_MXP__CONNECT_INFO_P5       0x0040
+#define CMN__CONNECT_INFO_DEVICE_TYPE  GENMASK_ULL(4, 0)
 
 /* PMU registers occupy the 3rd 4KB page of each node's region */
 #define CMN_PMU_OFFSET                 0x2000
@@ -400,7 +401,7 @@ static struct dentry *arm_cmn_debugfs;
 #ifdef CONFIG_DEBUG_FS
 static const char *arm_cmn_device_type(u8 type)
 {
-       switch(type) {
+       switch(FIELD_GET(CMN__CONNECT_INFO_DEVICE_TYPE, type)) {
                case 0x00: return "        |";
                case 0x01: return "  RN-I  |";
                case 0x02: return "  RN-D  |";