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

drm/hisilicon: Ensure LDI regs are properly configured.

to the 4.9-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: drm-hisilicon-ensure-ldi-regs-are-properly-configured.patch and it can be found in the queue-4.9 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 a2f042430784d86eb2b7a6d2a869f552da30edba Mon Sep 17 00:00:00 2001

From: Peter Griffin peter.griffin@linaro.org Date: Tue, 15 Aug 2017 15:14:25 +0100 Subject: drm/hisilicon: Ensure LDI regs are properly configured.

From: Peter Griffin peter.griffin@linaro.org

commit a2f042430784d86eb2b7a6d2a869f552da30edba upstream.

This patch fixes the following soft lockup: BUG: soft lockup - CPU#0 stuck for 23s! [weston:307]

On weston idle-timeout the IP is powered down and reset asserted. On weston resume we get a massive vblank IRQ storm due to the LDI registers having lost some state.

This state loss is caused by ade_crtc_atomic_begin() not calling ade_ldi_set_mode(). With this patch applied resuming from Weston idle-timeout works well.

Signed-off-by: Peter Griffin peter.griffin@linaro.org Tested-by: John Stultz john.stultz@linaro.org Reviewed-by: Xinliang Liu xinliang.liu@linaro.org Signed-off-by: Xinliang Liu xinliang.liu@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c | 3 +++ 1 file changed, 3 insertions(+)

--- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c +++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c @@ -521,9 +521,12 @@ static void ade_crtc_atomic_begin(struct { struct ade_crtc *acrtc = to_ade_crtc(crtc); struct ade_hw_ctx *ctx = acrtc->ctx; + struct drm_display_mode *mode = &crtc->state->mode; + struct drm_display_mode *adj_mode = &crtc->state->adjusted_mode;

if (!ctx->power_on) (void)ade_power_up(ctx); + ade_ldi_set_mode(acrtc, mode, adj_mode); }

static void ade_crtc_atomic_flush(struct drm_crtc *crtc,

Patches currently in stable-queue which might be from peter.griffin@linaro.org are

queue-4.9/drm-hisilicon-ensure-ldi-regs-are-properly-configured.patch