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%3Ba=su...

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