This is a note to let you know that I've just added the patch titled
drm/lima: set gp bus_stop bit before hard reset
to the 5.10-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:
drm-lima-set-gp-bus_stop-bit-before-hard-reset.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 01408317b5b07180e2ff57d5e64298106f5f166e
Author: Erico Nunes <nunes.erico@xxxxxxxxx>
Date: Wed Jan 24 03:59:43 2024 +0100
drm/lima: set gp bus_stop bit before hard reset
[ Upstream commit 27aa58ec85f973d98d336df7b7941149308db80f ]
This is required for reliable hard resets. Otherwise, doing a hard reset
while a task is still running (such as a task which is being stopped by
the drm_sched timeout handler) may result in random mmu write timeouts
or lockups which cause the entire gpu to hang.
Signed-off-by: Erico Nunes <nunes.erico@xxxxxxxxx>
Signed-off-by: Qiang Yu <yuq825@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20240124025947.2110659-5-nunes.erico@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/lima/lima_gp.c b/drivers/gpu/drm/lima/lima_gp.c
index ca3842f719842..82071835ec9ed 100644
--- a/drivers/gpu/drm/lima/lima_gp.c
+++ b/drivers/gpu/drm/lima/lima_gp.c
@@ -166,6 +166,11 @@ static void lima_gp_task_run(struct lima_sched_pipe *pipe,
gp_write(LIMA_GP_CMD, cmd);
}
+static int lima_gp_bus_stop_poll(struct lima_ip *ip)
+{
+ return !!(gp_read(LIMA_GP_STATUS) & LIMA_GP_STATUS_BUS_STOPPED);
+}
+
static int lima_gp_hard_reset_poll(struct lima_ip *ip)
{
gp_write(LIMA_GP_PERF_CNT_0_LIMIT, 0xC01A0000);
@@ -179,6 +184,13 @@ static int lima_gp_hard_reset(struct lima_ip *ip)
gp_write(LIMA_GP_PERF_CNT_0_LIMIT, 0xC0FFE000);
gp_write(LIMA_GP_INT_MASK, 0);
+
+ gp_write(LIMA_GP_CMD, LIMA_GP_CMD_STOP_BUS);
+ ret = lima_poll_timeout(ip, lima_gp_bus_stop_poll, 10, 100);
+ if (ret) {
+ dev_err(dev->dev, "%s bus stop timeout\n", lima_ip_name(ip));
+ return ret;
+ }
gp_write(LIMA_GP_CMD, LIMA_GP_CMD_RESET);
ret = lima_poll_timeout(ip, lima_gp_hard_reset_poll, 10, 100);
if (ret) {
