Patch "coresight: Fix disabling of CoreSight TPIU" has been added to the 4.4-stable tree

Patch "coresight: Fix disabling of CoreSight TPIU" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    coresight: Fix disabling of CoreSight TPIU

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     coresight-fix-disabling-of-coresight-tpiu.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Mar 22 14:57:33 CET 2018
From: Robert Walker <robert.walker@arm.com>
Date: Mon, 18 Dec 2017 11:05:44 -0700
Subject: coresight: Fix disabling of CoreSight TPIU

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/hwtracing/coresight/coresight-tpiu.c |   13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -45,8 +45,11 @@
 #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_
 {
 	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);
 }


Patches currently in stable-queue which might be from robert.walker@arm.com are

queue-4.4/coresight-fix-disabling-of-coresight-tpiu.patch