[PATCH 2/2] perf/arm-cmn: Update watchpoint format

Robin Murphy robin.murphy at arm.com
Thu Feb 24 10:41:22 PST 2022


>From CMN-650 onwards, some of the fields in the watchpoint config
registers moved subtly enough to easily overlook. Watchpoint events are
still only partially supported on newer IPs - which in itself deserves
noting - but were not intended to become any *less* functional than on
CMN-600.

Fixes: 60d1504070c2 ("perf/arm-cmn: Support new IP features")
Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---
 drivers/perf/arm-cmn.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index ba039a2532ad..e3bdb0a8689c 100644
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -71,9 +71,11 @@
 #define CMN_DTM_WPn(n)			(0x1A0 + (n) * 0x18)
 #define CMN_DTM_WPn_CONFIG(n)		(CMN_DTM_WPn(n) + 0x00)
 #define CMN_DTM_WPn_CONFIG_WP_DEV_SEL2	GENMASK_ULL(18,17)
-#define CMN_DTM_WPn_CONFIG_WP_COMBINE	BIT(6)
-#define CMN_DTM_WPn_CONFIG_WP_EXCLUSIVE	BIT(5)
-#define CMN_DTM_WPn_CONFIG_WP_GRP	BIT(4)
+#define CMN_DTM_WPn_CONFIG_WP_COMBINE	BIT(9)
+#define CMN_DTM_WPn_CONFIG_WP_EXCLUSIVE	BIT(8)
+#define CMN600_WPn_CONFIG_WP_COMBINE	BIT(6)
+#define CMN600_WPn_CONFIG_WP_EXCLUSIVE	BIT(5)
+#define CMN_DTM_WPn_CONFIG_WP_GRP	GENMASK_ULL(5, 4)
 #define CMN_DTM_WPn_CONFIG_WP_CHN_SEL	GENMASK_ULL(3, 1)
 #define CMN_DTM_WPn_CONFIG_WP_DEV_SEL	BIT(0)
 #define CMN_DTM_WPn_VAL(n)		(CMN_DTM_WPn(n) + 0x08)
@@ -155,6 +157,7 @@
 #define CMN_CONFIG_WP_COMBINE		GENMASK_ULL(27, 24)
 #define CMN_CONFIG_WP_DEV_SEL		GENMASK_ULL(50, 48)
 #define CMN_CONFIG_WP_CHN_SEL		GENMASK_ULL(55, 51)
+/* Note that we don't yet support the tertiary match group on newer IPs */
 #define CMN_CONFIG_WP_GRP		BIT_ULL(56)
 #define CMN_CONFIG_WP_EXCLUSIVE		BIT_ULL(57)
 #define CMN_CONFIG1_WP_VAL		GENMASK_ULL(63, 0)
@@ -908,15 +911,18 @@ static u32 arm_cmn_wp_config(struct perf_event *event)
 	u32 grp = CMN_EVENT_WP_GRP(event);
 	u32 exc = CMN_EVENT_WP_EXCLUSIVE(event);
 	u32 combine = CMN_EVENT_WP_COMBINE(event);
+	bool is_cmn600 = to_cmn(event->pmu)->model == CMN600;
 
 	config = FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_DEV_SEL, dev) |
 		 FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_CHN_SEL, chn) |
 		 FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_GRP, grp) |
-		 FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_EXCLUSIVE, exc) |
 		 FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_DEV_SEL2, dev >> 1);
+	if (exc)
+		config |= is_cmn600 ? CMN600_WPn_CONFIG_WP_EXCLUSIVE :
+				      CMN_DTM_WPn_CONFIG_WP_EXCLUSIVE;
 	if (combine && !grp)
-		config |= CMN_DTM_WPn_CONFIG_WP_COMBINE;
-
+		config |= is_cmn600 ? CMN600_WPn_CONFIG_WP_COMBINE :
+				      CMN_DTM_WPn_CONFIG_WP_COMBINE;
 	return config;
 }
 
-- 
2.28.0.dirty




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