This is a note to let you know that I've just added the patch titled
intel_th: gth: Fix the window switching sequence
to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 87c0b9c79ec136ea76a14a88d675a746bc6a87f9 Mon Sep 17 00:00:00 2001
From: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Date: Mon, 28 Oct 2019 09:06:45 +0200
Subject: intel_th: gth: Fix the window switching sequence
Commit 8116db57cf16 ("intel_th: Add switch triggering support") added
a trigger assertion of the CTS, but forgot to de-assert it at the end
of the sequence. This results in window switches randomly not happening.
Fix that by de-asserting the trigger at the end of the window switch
sequence.
Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Fixes: 8116db57cf16 ("intel_th: Add switch triggering support")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20191028070651.9770-2-alexander.shishkin@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/hwtracing/intel_th/gth.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/hwtracing/intel_th/gth.c b/drivers/hwtracing/intel_th/gth.c
index fa9d34af87ac..f72803a02391 100644
--- a/drivers/hwtracing/intel_th/gth.c
+++ b/drivers/hwtracing/intel_th/gth.c
@@ -626,6 +626,9 @@ static void intel_th_gth_switch(struct intel_th_device *thdev,
if (!count)
dev_dbg(&thdev->dev, "timeout waiting for CTS Trigger\n");
+ /* De-assert the trigger */
+ iowrite32(0, gth->base + REG_CTS_CTL);
+
intel_th_gth_stop(gth, output, false);
intel_th_gth_start(gth, output);
}
--
2.23.0
