[PATCH v2] drm/rockchip: Don't continue trying to enable crtc on failure

[Sean Paul]

On Wed, Aug 17, 2016 at 3:28 AM, Yakir Yang <ykk at rock-chips.com> wrote:
> Sean,
>
> On 08/16/2016 07:12 AM, Sean Paul wrote:
>>
>> If vop_enable fails, don't continue on, it causes system hangs.
>>
>> Signed-off-by: Sean Paul <seanpaul at chromium.org>
>
>
> Also meet this problem on my Rk3399 Kevin board. VOP just failed to get the
> pm_runtime at resume time, but ｄｒｉｖer still just continue without anything
> enable rightly, oops, and then system crashed :(
>
> So this patch looks good to me, and also fix my problem, thanks:
>
> Ｒｅviewed-by: Yakir Yang <ykk at rock-chips.com>
> Tested-by: Yakir Yang <ykk at rock-chips.com>
>

Applied to -misc

Sean

> Thanks,
> - Yakir
>
>> ---
>>
>> This patch uses the new DRM_DEV_ERROR logging, so it should be applied on
>> top of "[PATCH 2/2] drm/rockchip: Use DRM_DEV_ERROR in vop".
>>
>> Changes in v2:
>>         - Escalate dev_err to WARN_ON for clk_enable failures (Daniel
>> Vetter)
>>
>> Sean
>>
>>
>>   drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 31
>> ++++++++++++++++-------------
>>   1 file changed, 17 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> index ec8ad00..a176d03 100644
>> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
>> @@ -428,7 +428,7 @@ static void vop_dsp_hold_valid_irq_disable(struct vop
>> *vop)
>>         spin_unlock_irqrestore(&vop->irq_lock, flags);
>>   }
>>   -static void vop_enable(struct drm_crtc *crtc)
>> +static int vop_enable(struct drm_crtc *crtc)
>>   {
>>         struct vop *vop = to_vop(crtc);
>>         int ret;
>> @@ -436,26 +436,20 @@ static void vop_enable(struct drm_crtc *crtc)
>>         ret = pm_runtime_get_sync(vop->dev);
>>         if (ret < 0) {
>>                 dev_err(vop->dev, "failed to get pm runtime: %d\n", ret);
>> -               return;
>> +               goto err_put_pm_runtime;
>>         }
>>         ret = clk_enable(vop->hclk);
>> -       if (ret < 0) {
>> -               dev_err(vop->dev, "failed to enable hclk - %d\n", ret);
>> -               return;
>> -       }
>> +       if (WARN_ON(ret < 0))
>> +               goto err_put_pm_runtime;
>>         ret = clk_enable(vop->dclk);
>> -       if (ret < 0) {
>> -               dev_err(vop->dev, "failed to enable dclk - %d\n", ret);
>> +       if (WARN_ON(ret < 0))
>>                 goto err_disable_hclk;
>> -       }
>>         ret = clk_enable(vop->aclk);
>> -       if (ret < 0) {
>> -               dev_err(vop->dev, "failed to enable aclk - %d\n", ret);
>> +       if (WARN_ON(ret < 0))
>>                 goto err_disable_dclk;
>> -       }
>>         /*
>>          * Slave iommu shares power, irq and clock with vop.  It was
>> associated
>> @@ -485,7 +479,7 @@ static void vop_enable(struct drm_crtc *crtc)
>>         drm_crtc_vblank_on(crtc);
>>   -     return;
>> +       return 0;
>>     err_disable_aclk:
>>         clk_disable(vop->aclk);
>> @@ -493,6 +487,9 @@ err_disable_dclk:
>>         clk_disable(vop->dclk);
>>   err_disable_hclk:
>>         clk_disable(vop->hclk);
>> +err_put_pm_runtime:
>> +       pm_runtime_put_sync(vop->dev);
>> +       return ret;
>>   }
>>     static void vop_crtc_disable(struct drm_crtc *crtc)
>> @@ -912,10 +909,16 @@ static void vop_crtc_enable(struct drm_crtc *crtc)
>>         u16 vact_st = adjusted_mode->vtotal - adjusted_mode->vsync_start;
>>         u16 vact_end = vact_st + vdisplay;
>>         uint32_t val;
>> +       int ret;
>>         WARN_ON(vop->event);
>>   -     vop_enable(crtc);
>> +       ret = vop_enable(crtc);
>> +       if (ret) {
>> +               DRM_DEV_ERROR(vop->dev, "Failed to enable vop (%d)\n",
>> ret);
>> +               return;
>> +       }
>> +
>>         /*
>>          * If dclk rate is zero, mean that scanout is stop,
>>          * we don't need wait any more.
>
>
>