2017-06-29 20:56:46

by Peter Griffin

[permalink] [raw]
Subject: [RESEND PATCH] drm/hisilicon: Ensure LDI regs are properly configured.

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 <[email protected]>
---
drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
index c96c228..72c6357 100644
--- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
+++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
@@ -519,9 +519,12 @@ static void ade_crtc_atomic_begin(struct drm_crtc *crtc,
{
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,
--
2.7.4


2017-06-29 21:10:19

by John Stultz

[permalink] [raw]
Subject: Re: [RESEND PATCH] drm/hisilicon: Ensure LDI regs are properly configured.

On Thu, Jun 29, 2017 at 1:54 PM, Peter Griffin <[email protected]> wrote:
> 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 <[email protected]>

While the issue hasn't seemingly come up with Android, I've been
running with this patch in my tree for a while without issue. So..
Tested-by: John Stultz <[email protected]>

thanks
-john

2017-06-30 05:56:02

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: [RESEND PATCH] drm/hisilicon: Ensure LDI regs are properly configured.

On Thu, Jun 29, 2017 at 09:54:38PM +0100, Peter Griffin wrote:
> 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 <[email protected]>
> ---
> drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c | 3 +++
> 1 file changed, 3 insertions(+)
>

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>