[PATCH] coresight: etm4x: Ensure default perf settings filter user/kernel

[Mike Leach]

Moving from using an address filter to trace the default "all addresses"
range to no filtering to acheive the same result, has caused the perf
filtering of kernel/user address spaces from not working unless an
explicit address filter was used.

This due to the global TRCVICTLR exception level filtering not being set
correctly.

This patch fixes this.

Reported-by: Leo Yan <leo.yan at linaro.org>
Signed-off-by: Mike Leach <mike.leach at linaro.org>
---
 drivers/hwtracing/coresight/coresight-etm4x.c | 11 +++++++++++
 drivers/hwtracing/coresight/coresight-etm4x.h |  3 +++
 2 files changed, 14 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 8b0634ebef77..d0f800753590 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -52,6 +52,7 @@ static struct etmv4_drvdata *etmdrvdata[NR_CPUS];
 static void etm4_set_default_config(struct etmv4_config *config);
 static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,
 				  struct perf_event *event);
+static u64 etm4_get_access_type(struct etmv4_config *config);
 
 static enum cpuhp_state hp_online;
 
@@ -785,6 +786,8 @@ static void etm4_init_arch_data(void *info)
 
 static void etm4_set_default_config(struct etmv4_config *config)
 {
+	u64 access_type;
+
 	/* disable all events tracing */
 	config->eventctrl0 = 0x0;
 	config->eventctrl1 = 0x0;
@@ -800,6 +803,14 @@ static void etm4_set_default_config(struct etmv4_config *config)
 
 	/* TRCVICTLR::EVENT = 0x01, select the always on logic */
 	config->vinst_ctrl = BIT(0);
+
+	/*
+	 * TRCVICTLR::EXLEVEL_NS:EXLEVELS: Set kernel / user filtering
+	 * bits in vinst, same bit pattern as address comparator acc values
+	 * but offset in this register
+	 */
+	access_type = etm4_get_access_type(config) << ETM_EXLEVEL_VINST_OFFSET;
+	config->vinst_ctrl |= (u32)access_type;
 }
 
 static u64 etm4_get_ns_access_type(struct etmv4_config *config)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
index b8283e1d6d88..369abc25c597 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.h
+++ b/drivers/hwtracing/coresight/coresight-etm4x.h
@@ -192,6 +192,9 @@
 #define ETM_EXLEVEL_NS_HYP		BIT(14)
 #define ETM_EXLEVEL_NS_NA		BIT(15)
 
+/* access level control in VINST - same bits as TRCACATRn but offset */
+#define ETM_EXLEVEL_VINST_OFFSET	8
+
 /* secure / non secure masks - TRCVICTLR, IDR3 */
 #define ETM_EXLEVEL_S_VICTLR_MASK	GENMASK(19, 16)
 /* NS MON (EL3) mode never implemented */
-- 
2.17.1