linux-kernel - [PATCH 07/10] coresight: etm4x: configuring include/exclude function

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Date:	Mon, 18 Jul 2016 13:51:28 -0600
From:	Mathieu Poirier <mathieu.poirier@...aro.org>
To:	linux-arm-kernel@...ts.infradead.org
Cc:	linux-kernel@...r.kernel.org, alexander.shishkin@...ux.intel.com,
	Mathieu Poirier <mathieu.poirier@...aro.org>
Subject: [PATCH 07/10] coresight: etm4x: configuring include/exclude function

The include/exclude function of a tracer is applicable to address
range and start/stop filters.  To avoid duplication and reuse code
moving the include/exclude configuration to a function of its own.

Signed-off-by: Mathieu Poirier <mathieu.poirier@...aro.org>
---
 drivers/hwtracing/coresight/coresight-etm4x.c | 35 +++++++++++++++++++--------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 4a4d2ef35ad6..9eba6d8f4633 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -213,13 +213,6 @@ static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,
 	/* Always start from the default config */
 	etm4_set_default(config);
 
-	/*
-	 * By default the tracers are configured to trace the whole address
-	 * range.  Narrow the field only if requested by user space.
-	 */
-	if (config->mode)
-		etm4_config_trace_mode(config);
-
 	/* Go from generic option to ETMv4 specifics */
 	if (attr->config & BIT(ETM_OPT_CYCACC))
 		config->cfg |= ETMv4_MODE_CYCACC;
@@ -584,14 +577,28 @@ static void etm4_set_default_config(struct etmv4_config *config)
 	config->vinst_ctrl |= BIT(0);
 }
 
-static void etm4_set_comparator_filter(struct etmv4_config *config,
-				       u64 start, u64 stop, int comparator)
+static u64 etm4_get_access_type(struct etmv4_config *config)
 {
 	u64 access_type = 0;
 
-	/* EXLEVEL_NS, bits[12:15], always stay away from hypervisor mode. */
+	/*
+	 * EXLEVEL_NS, bits[15:12]
+	 * The Exception levels are:
+	 *   Bit[12] Exception level 0 - Application
+	 *   Bit[13] Exception level 1 - OS
+	 *   Bit[14] Exception level 2 - Hypervisor
+	 *   Bit[15] Never implemented
+	 *
+	 * Always stay away from hypervisor mode.
+	 */
 	access_type = ETM_EXLEVEL_NS_HYP;
 
+	if (config->mode & ETM_MODE_EXCL_KERN)
+		access_type |= ETM_EXLEVEL_NS_OS;
+
+	if (config->mode & ETM_MODE_EXCL_USER)
+		access_type |= ETM_EXLEVEL_NS_APP;
+
 	/*
 	 * EXLEVEL_S, bits[11:8], don't trace anything happening
 	 * in secure state.
@@ -600,6 +607,14 @@ static void etm4_set_comparator_filter(struct etmv4_config *config,
 			ETM_EXLEVEL_S_OS	|
 			ETM_EXLEVEL_S_HYP);
 
+	return access_type;
+}
+
+static void etm4_set_comparator_filter(struct etmv4_config *config,
+				       u64 start, u64 stop, int comparator)
+{
+	u64 access_type = etm4_get_access_type(config);
+
 	/* First half of default address comparator */
 	config->addr_val[comparator] = start;
 	config->addr_acc[comparator] = access_type;
-- 
2.7.4