[PATCH AUTOSEL for 4.14 45/67] coresight: Fix disabling of CoreSight TPIU

Sasha Levin
2018-03-08T04:57:51Z

From: Robert Walker <robert.walker@arm.com>

[ Upstream commit 11595db8e17faaa05fadc25746c870e31276962f ]

The CoreSight TPIU should be disabled when tracing to other sinks to allow
them to operate at full bandwidth.

This patch fixes tpiu_disable_hw() to correctly disable the TPIU by
configuring the TPIU to stop on flush, initiating a manual flush, waiting
for the flush to complete and then waits for the TPIU to indicate it has
stopped.

Signed-off-by: Robert Walker <robert.walker@arm.com>
Tested-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/hwtracing/coresight/coresight-tpiu.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
index d7a3e453016d..735dca089389 100644
--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -46,8 +46,11 @@
#define TPIU_ITATBCTR0 0xef8

/** register definition **/
+/* FFSR - 0x300 */
+#define FFSR_FT_STOPPED BIT(1)
/* FFCR - 0x304 */
#define FFCR_FON_MAN BIT(6)
+#define FFCR_STOP_FI BIT(12)

/**
* @base: memory mapped base address for this component.
@@ -85,10 +88,14 @@ static void tpiu_disable_hw(struct tpiu_drvdata *drvdata)
{
CS_UNLOCK(drvdata->base);

- /* Clear formatter controle reg. */
- writel_relaxed(0x0, drvdata->base + TPIU_FFCR);
+ /* Clear formatter and stop on flush */
+ writel_relaxed(FFCR_STOP_FI, drvdata->base + TPIU_FFCR);
/* Generate manual flush */
- writel_relaxed(FFCR_FON_MAN, drvdata->base + TPIU_FFCR);
+ writel_relaxed(FFCR_STOP_FI | FFCR_FON_MAN, drvdata->base + TPIU_FFCR);
+ /* Wait for flush to complete */
+ coresight_timeout(drvdata->base, TPIU_FFCR, FFCR_FON_MAN, 0);
+ /* Wait for formatter to stop */
+ coresight_timeout(drvdata->base, TPIU_FFSR, FFSR_FT_STOPPED, 1);

CS_LOCK(drvdata->base);
}
--
2.14.1