diff mbox

[v2] coresight: etm4x: Fix enabling of cycle accurate tracing in perf.

Message ID 1483523231-23993-1-git-send-email-mike.leach@linaro.org
State Accepted
Commit ae3fabcda00de54029b5342a3d6d82d65e7c4e6b
Headers show

Commit Message

Mike Leach Jan. 4, 2017, 9:47 a.m. UTC
Using perf record 'cyclacc' option in cs_etm event was not setting up cycle
accurate trace correctly.

Corrects bit set in TRCCONFIGR to enable cycle accurate trace.
Programs TRCCCCTLR with a valid threshold value as required by ETMv4 spec.

Signed-off-by: Mike Leach <mike.leach@linaro.org>

---
 drivers/hwtracing/coresight/coresight-etm4x.c | 7 +++++--
 drivers/hwtracing/coresight/coresight-etm4x.h | 1 +
 2 files changed, 6 insertions(+), 2 deletions(-)

-- 
2.7.4


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Comments

Mathieu Poirier Jan. 4, 2017, 5:23 p.m. UTC | #1
On 4 January 2017 at 02:47, Mike Leach <mike.leach@linaro.org> wrote:
> Using perf record 'cyclacc' option in cs_etm event was not setting up cycle

> accurate trace correctly.

>

> Corrects bit set in TRCCONFIGR to enable cycle accurate trace.

> Programs TRCCCCTLR with a valid threshold value as required by ETMv4 spec.

>

> Signed-off-by: Mike Leach <mike.leach@linaro.org>

> ---

>  drivers/hwtracing/coresight/coresight-etm4x.c | 7 +++++--

>  drivers/hwtracing/coresight/coresight-etm4x.h | 1 +

>  2 files changed, 6 insertions(+), 2 deletions(-)

>

> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c

> index 4db8d6a..c5a65d1 100644

> --- a/drivers/hwtracing/coresight/coresight-etm4x.c

> +++ b/drivers/hwtracing/coresight/coresight-etm4x.c

> @@ -216,8 +216,11 @@ static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,

>                 goto out;

>

>         /* Go from generic option to ETMv4 specifics */

> -       if (attr->config & BIT(ETM_OPT_CYCACC))

> -               config->cfg |= ETMv4_MODE_CYCACC;

> +       if (attr->config & BIT(ETM_OPT_CYCACC)) {

> +               config->cfg |= BIT(4);

> +               /* TRM: Must program this for cycacc to work */

> +               config->ccctlr = ETM_CYC_THRESHOLD_DEFAULT;

> +       }

>         if (attr->config & BIT(ETM_OPT_TS))

>                 config->cfg |= ETMv4_MODE_TIMESTAMP;

>

> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h

> index ba8d3f8..b3b5ea7 100644

> --- a/drivers/hwtracing/coresight/coresight-etm4x.h

> +++ b/drivers/hwtracing/coresight/coresight-etm4x.h

> @@ -146,6 +146,7 @@

>  #define ETM_ARCH_V4                    0x40

>  #define ETMv4_SYNC_MASK                        0x1F

>  #define ETM_CYC_THRESHOLD_MASK         0xFFF

> +#define ETM_CYC_THRESHOLD_DEFAULT       0x100

>  #define ETMv4_EVENT_MASK               0xFF

>  #define ETM_CNTR_MAX_VAL               0xFFFF

>  #define ETM_TRACEID_MASK               0x3f

> --

> 2.7.4

>


Applied - thanks.

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diff mbox

Patch

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 4db8d6a..c5a65d1 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -216,8 +216,11 @@  static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,
 		goto out;
 
 	/* Go from generic option to ETMv4 specifics */
-	if (attr->config & BIT(ETM_OPT_CYCACC))
-		config->cfg |= ETMv4_MODE_CYCACC;
+	if (attr->config & BIT(ETM_OPT_CYCACC)) {
+		config->cfg |= BIT(4);
+		/* TRM: Must program this for cycacc to work */
+		config->ccctlr = ETM_CYC_THRESHOLD_DEFAULT;
+	}
 	if (attr->config & BIT(ETM_OPT_TS))
 		config->cfg |= ETMv4_MODE_TIMESTAMP;
 
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
index ba8d3f8..b3b5ea7 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.h
+++ b/drivers/hwtracing/coresight/coresight-etm4x.h
@@ -146,6 +146,7 @@ 
 #define ETM_ARCH_V4			0x40
 #define ETMv4_SYNC_MASK			0x1F
 #define ETM_CYC_THRESHOLD_MASK		0xFFF
+#define ETM_CYC_THRESHOLD_DEFAULT       0x100
 #define ETMv4_EVENT_MASK		0xFF
 #define ETM_CNTR_MAX_VAL		0xFFFF
 #define ETM_TRACEID_MASK		0x3f