* Re: [PATCH v5 3/6] drm/mediatek: Detect CMDQ execution timeout
[not found] ` <20211027021857.20816-4-jason-jh.lin@mediatek.com>
@ 2021-10-27 9:31 ` Fei Shao
2021-10-27 23:47 ` Chun-Kuang Hu
0 siblings, 1 reply; 6+ messages in thread
From: Fei Shao @ 2021-10-27 9:31 UTC (permalink / raw)
To: jason-jh.lin
Cc: Chun-Kuang Hu, Philipp Zabel, Matthias Brugger, Jassi Brar,
Yongqiang Niu, David Airlie, Daniel Vetter, dri-devel,
linux-mediatek, linux-arm-kernel, linux-kernel, hsinyi,
nancy.lin, singo.chang
Hi Jason,
On Wed, Oct 27, 2021 at 10:19 AM jason-jh.lin <jason-jh.lin@mediatek.com> wrote:
>
> From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
>
> CMDQ is used to update display register in vblank period, so
> it should be execute in next 2 vblank. One vblank interrupt
> before send message (occasionally) and one vblank interrupt
> after cmdq done. If it fail to execute in next 3 vblank,
> tiemout happen.
>
> Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> Signed-off-by: jason-jh.lin <jason-jh.lin@mediatek.com>
> Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 20 ++++++++++++++++++--
> 1 file changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index e23e3224ac67..dad1f85ee315 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -54,6 +54,7 @@ struct mtk_drm_crtc {
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> struct cmdq_client cmdq_client;
> u32 cmdq_event;
> + u32 cmdq_vblank_cnt;
> #endif
>
> struct device *mmsys_dev;
> @@ -227,7 +228,10 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
> static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> {
> struct cmdq_cb_data *data = mssg;
> + struct cmdq_client *cmdq_cl = container_of(cl, struct cmdq_client, client);
> + struct mtk_drm_crtc *mtk_crtc = container_of(cmdq_cl, struct mtk_drm_crtc, cmdq_client);
>
> + mtk_crtc->cmdq_vblank_cnt = 0;
> cmdq_pkt_destroy(data->pkt);
> }
> #endif
> @@ -483,6 +487,15 @@ static void mtk_drm_crtc_update_config(struct mtk_drm_crtc *mtk_crtc,
> cmdq_handle->pa_base,
> cmdq_handle->cmd_buf_size,
> DMA_TO_DEVICE);
> + /*
> + * CMDQ command should execute in next 3 vblank.
> + * One vblank interrupt before send message (occasionally)
> + * and one vblank interrupt after cmdq done,
> + * so it's timeout after 3 vblank interrupt.
> + * If it fail to execute in next 3 vblank, timeout happen.
> + */
> + mtk_crtc->cmdq_vblank_cnt = 3;
> +
> mbox_send_message(mtk_crtc->cmdq_client.chan, cmdq_handle);
> mbox_client_txdone(mtk_crtc->cmdq_client.chan, 0);
> }
> @@ -499,11 +512,14 @@ static void mtk_crtc_ddp_irq(void *data)
>
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> if (!priv->data->shadow_register && !mtk_crtc->cmdq_client.chan)
> + mtk_crtc_ddp_config(crtc, NULL);
> + else if (mtk_crtc->cmdq_vblank_cnt > 0 && --mtk_crtc->cmdq_vblank_cnt == 0)
I think atomic_dec_and_test() does what you want to do here.
> + DRM_ERROR("mtk_crtc %d CMDQ execute command timeout!\n",
> + drm_crtc_index(&mtk_crtc->base));
> #else
> if (!priv->data->shadow_register)
> -#endif
> mtk_crtc_ddp_config(crtc, NULL);
> -
> +#endif
> mtk_drm_finish_page_flip(mtk_crtc);
> }
>
> --
> 2.18.0
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v5 5/6] drm/mediatek: Add mbox_free_channel in mtk_drm_crtc_destroy
[not found] ` <20211027021857.20816-6-jason-jh.lin@mediatek.com>
@ 2021-10-27 23:30 ` Chun-Kuang Hu
0 siblings, 0 replies; 6+ messages in thread
From: Chun-Kuang Hu @ 2021-10-27 23:30 UTC (permalink / raw)
To: jason-jh.lin
Cc: Chun-Kuang Hu, Philipp Zabel, Matthias Brugger, Jassi Brar,
Yongqiang Niu, David Airlie, Daniel Vetter, DRI Development,
moderated list:ARM/Mediatek SoC support, Linux ARM, linux-kernel,
Hsin-Yi Wang, fshao, Nancy Lin, singo.chang
Hi, Jason:
jason-jh.lin <jason-jh.lin@mediatek.com> 於 2021年10月27日 週三 上午10:19寫道：
>
> Add mbox_free_channel in mtk_drm_crtc_destroy.
>
> Signed-off-by: jason-jh.lin <jason-jh.lin@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index ffa54b416ca7..31f05efc1bc0 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -156,6 +156,10 @@ static void mtk_drm_crtc_destroy(struct drm_crtc *crtc)
> mtk_mutex_put(mtk_crtc->mutex);
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> mtk_drm_cmdq_pkt_destroy(&mtk_crtc->cmdq_handle);
> +
> + if (mtk_crtc->cmdq_client.chan)
> + mbox_free_channel(mtk_crtc->cmdq_client.chan);
> + mtk_crtc->cmdq_client.chan = NULL;
Except the indent,
Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> #endif
> drm_crtc_cleanup(crtc);
> }
> --
> 2.18.0
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v5 4/6] drm/mediatek: Add cmdq_handle in mtk_crtc
[not found] ` <20211027021857.20816-5-jason-jh.lin@mediatek.com>
@ 2021-10-27 23:32 ` Chun-Kuang Hu
0 siblings, 0 replies; 6+ messages in thread
From: Chun-Kuang Hu @ 2021-10-27 23:32 UTC (permalink / raw)
To: jason-jh.lin
Cc: Chun-Kuang Hu, Philipp Zabel, Matthias Brugger, Jassi Brar,
Yongqiang Niu, David Airlie, Daniel Vetter, DRI Development,
moderated list:ARM/Mediatek SoC support, Linux ARM, linux-kernel,
Hsin-Yi Wang, fshao, Nancy Lin, singo.chang
Hi, Jason:
jason-jh.lin <jason-jh.lin@mediatek.com> 於 2021年10月27日 週三 上午10:19寫道：
>
> From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
>
> One mtk_crtc need just one cmdq_handle, so add one cmdq_handle
> in mtk_crtc to prevent frequently allocation and free of
> cmdq_handle.
Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
>
> Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> Signed-off-by: jason-jh.lin <jason-jh.lin@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 62 +++++++++++++++++++++++--
> 1 file changed, 57 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index dad1f85ee315..ffa54b416ca7 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -53,6 +53,7 @@ struct mtk_drm_crtc {
>
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> struct cmdq_client cmdq_client;
> + struct cmdq_pkt cmdq_handle;
> u32 cmdq_event;
> u32 cmdq_vblank_cnt;
> #endif
> @@ -107,12 +108,55 @@ static void mtk_drm_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
> }
> }
>
> +#if IS_REACHABLE(CONFIG_MTK_CMDQ)
> +static int mtk_drm_cmdq_pkt_create(struct cmdq_client *client, struct cmdq_pkt *pkt,
> + size_t size)
> +{
> + struct device *dev;
> + dma_addr_t dma_addr;
> +
> + pkt->va_base = kzalloc(size, GFP_KERNEL);
> + if (!pkt->va_base) {
> + kfree(pkt);
> + return -ENOMEM;
> + }
> + pkt->buf_size = size;
> + pkt->cl = (void *)client;
> +
> + dev = client->chan->mbox->dev;
> + dma_addr = dma_map_single(dev, pkt->va_base, pkt->buf_size,
> + DMA_TO_DEVICE);
> + if (dma_mapping_error(dev, dma_addr)) {
> + dev_err(dev, "dma map failed, size=%u\n", (u32)(u64)size);
> + kfree(pkt->va_base);
> + kfree(pkt);
> + return -ENOMEM;
> + }
> +
> + pkt->pa_base = dma_addr;
> +
> + return 0;
> +}
> +
> +static void mtk_drm_cmdq_pkt_destroy(struct cmdq_pkt *pkt)
> +{
> + struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
> +
> + dma_unmap_single(client->chan->mbox->dev, pkt->pa_base, pkt->buf_size,
> + DMA_TO_DEVICE);
> + kfree(pkt->va_base);
> + kfree(pkt);
> +}
> +#endif
> +
> static void mtk_drm_crtc_destroy(struct drm_crtc *crtc)
> {
> struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
>
> mtk_mutex_put(mtk_crtc->mutex);
> -
> +#if IS_REACHABLE(CONFIG_MTK_CMDQ)
> + mtk_drm_cmdq_pkt_destroy(&mtk_crtc->cmdq_handle);
> +#endif
> drm_crtc_cleanup(crtc);
> }
>
> @@ -227,12 +271,10 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> {
> - struct cmdq_cb_data *data = mssg;
> struct cmdq_client *cmdq_cl = container_of(cl, struct cmdq_client, client);
> struct mtk_drm_crtc *mtk_crtc = container_of(cmdq_cl, struct mtk_drm_crtc, cmdq_client);
>
> mtk_crtc->cmdq_vblank_cnt = 0;
> - cmdq_pkt_destroy(data->pkt);
> }
> #endif
>
> @@ -438,7 +480,7 @@ static void mtk_drm_crtc_update_config(struct mtk_drm_crtc *mtk_crtc,
> bool needs_vblank)
> {
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> - struct cmdq_pkt *cmdq_handle;
> + struct cmdq_pkt *cmdq_handle = &mtk_crtc->cmdq_handle;
> #endif
> struct drm_crtc *crtc = &mtk_crtc->base;
> struct mtk_drm_private *priv = crtc->dev->dev_private;
> @@ -478,7 +520,7 @@ static void mtk_drm_crtc_update_config(struct mtk_drm_crtc *mtk_crtc,
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> if (mtk_crtc->cmdq_client.chan) {
> mbox_flush(mtk_crtc->cmdq_client.chan, 2000);
> - cmdq_handle = cmdq_pkt_create(&mtk_crtc->cmdq_client, PAGE_SIZE);
> + cmdq_handle->cmd_buf_size = 0;
> cmdq_pkt_clear_event(cmdq_handle, mtk_crtc->cmdq_event);
> cmdq_pkt_wfe(cmdq_handle, mtk_crtc->cmdq_event, false);
> mtk_crtc_ddp_config(crtc, cmdq_handle);
> @@ -877,6 +919,16 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> drm_crtc_index(&mtk_crtc->base));
> mbox_free_channel(mtk_crtc->cmdq_client.chan);
> mtk_crtc->cmdq_client.chan = NULL;
> + } else {
> + ret = mtk_drm_cmdq_pkt_create(&mtk_crtc->cmdq_client,
> + &mtk_crtc->cmdq_handle,
> + PAGE_SIZE);
> + if (ret) {
> + dev_dbg(dev, "mtk_crtc %d failed to create cmdq packet\n",
> + drm_crtc_index(&mtk_crtc->base));
> + mbox_free_channel(mtk_crtc->cmdq_client.chan);
> + mtk_crtc->cmdq_client.chan = NULL;
> + }
> }
> }
> #endif
> --
> 2.18.0
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v5 3/6] drm/mediatek: Detect CMDQ execution timeout
2021-10-27 9:31 ` [PATCH v5 3/6] drm/mediatek: Detect CMDQ execution timeout Fei Shao
@ 2021-10-27 23:47 ` Chun-Kuang Hu
2021-10-28 3:19 ` Fei Shao
0 siblings, 1 reply; 6+ messages in thread
From: Chun-Kuang Hu @ 2021-10-27 23:47 UTC (permalink / raw)
To: Fei Shao
Cc: jason-jh.lin, Chun-Kuang Hu, Philipp Zabel, Matthias Brugger,
Jassi Brar, Yongqiang Niu, David Airlie, Daniel Vetter,
DRI Development, moderated list:ARM/Mediatek SoC support,
Linux ARM, linux-kernel, Hsin-Yi Wang, Nancy Lin, singo.chang
Hi, Fei:
Fei Shao <fshao@chromium.org> 於 2021年10月27日 週三 下午5:32寫道：
>
> Hi Jason,
>
> On Wed, Oct 27, 2021 at 10:19 AM jason-jh.lin <jason-jh.lin@mediatek.com> wrote:
> >
> > From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> >
> > CMDQ is used to update display register in vblank period, so
> > it should be execute in next 2 vblank. One vblank interrupt
> > before send message (occasionally) and one vblank interrupt
> > after cmdq done. If it fail to execute in next 3 vblank,
> > tiemout happen.
> >
> > Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > Signed-off-by: jason-jh.lin <jason-jh.lin@mediatek.com>
> > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > ---
> > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 20 ++++++++++++++++++--
> > 1 file changed, 18 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > index e23e3224ac67..dad1f85ee315 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > @@ -54,6 +54,7 @@ struct mtk_drm_crtc {
> > #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > struct cmdq_client cmdq_client;
> > u32 cmdq_event;
> > + u32 cmdq_vblank_cnt;
> > #endif
> >
> > struct device *mmsys_dev;
> > @@ -227,7 +228,10 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
> > static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> > {
> > struct cmdq_cb_data *data = mssg;
> > + struct cmdq_client *cmdq_cl = container_of(cl, struct cmdq_client, client);
> > + struct mtk_drm_crtc *mtk_crtc = container_of(cmdq_cl, struct mtk_drm_crtc, cmdq_client);
> >
> > + mtk_crtc->cmdq_vblank_cnt = 0;
> > cmdq_pkt_destroy(data->pkt);
> > }
> > #endif
> > @@ -483,6 +487,15 @@ static void mtk_drm_crtc_update_config(struct mtk_drm_crtc *mtk_crtc,
> > cmdq_handle->pa_base,
> > cmdq_handle->cmd_buf_size,
> > DMA_TO_DEVICE);
> > + /*
> > + * CMDQ command should execute in next 3 vblank.
> > + * One vblank interrupt before send message (occasionally)
> > + * and one vblank interrupt after cmdq done,
> > + * so it's timeout after 3 vblank interrupt.
> > + * If it fail to execute in next 3 vblank, timeout happen.
> > + */
> > + mtk_crtc->cmdq_vblank_cnt = 3;
> > +
> > mbox_send_message(mtk_crtc->cmdq_client.chan, cmdq_handle);
> > mbox_client_txdone(mtk_crtc->cmdq_client.chan, 0);
> > }
> > @@ -499,11 +512,14 @@ static void mtk_crtc_ddp_irq(void *data)
> >
> > #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > if (!priv->data->shadow_register && !mtk_crtc->cmdq_client.chan)
> > + mtk_crtc_ddp_config(crtc, NULL);
> > + else if (mtk_crtc->cmdq_vblank_cnt > 0 && --mtk_crtc->cmdq_vblank_cnt == 0)
> I think atomic_dec_and_test() does what you want to do here.
I think this operation is not necessary to be atomic operation, and
this statement could be reduced to
else if (--mtk_crtc->cmdq_vblank_cnt == 0)
>
>
>
>
> > + DRM_ERROR("mtk_crtc %d CMDQ execute command timeout!\n",
> > + drm_crtc_index(&mtk_crtc->base));
> > #else
> > if (!priv->data->shadow_register)
> > -#endif
> > mtk_crtc_ddp_config(crtc, NULL);
> > -
> > +#endif
> > mtk_drm_finish_page_flip(mtk_crtc);
> > }
> >
> > --
> > 2.18.0
> >
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v5 3/6] drm/mediatek: Detect CMDQ execution timeout
2021-10-27 23:47 ` Chun-Kuang Hu
@ 2021-10-28 3:19 ` Fei Shao
2021-11-17 23:51 ` Chun-Kuang Hu
0 siblings, 1 reply; 6+ messages in thread
From: Fei Shao @ 2021-10-28 3:19 UTC (permalink / raw)
To: Chun-Kuang Hu
Cc: jason-jh.lin, Philipp Zabel, Matthias Brugger, Jassi Brar,
Yongqiang Niu, David Airlie, Daniel Vetter, DRI Development,
moderated list:ARM/Mediatek SoC support, Linux ARM, linux-kernel,
Hsin-Yi Wang, Nancy Lin, singo.chang
Hi Chun-Kuang,
On Thu, Oct 28, 2021 at 7:47 AM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote:
>
> Hi, Fei:
>
> Fei Shao <fshao@chromium.org> 於 2021年10月27日 週三 下午5:32寫道：
> >
> > Hi Jason,
> >
> > On Wed, Oct 27, 2021 at 10:19 AM jason-jh.lin <jason-jh.lin@mediatek.com> wrote:
> > >
> > > From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > >
> > > CMDQ is used to update display register in vblank period, so
> > > it should be execute in next 2 vblank. One vblank interrupt
> > > before send message (occasionally) and one vblank interrupt
> > > after cmdq done. If it fail to execute in next 3 vblank,
> > > tiemout happen.
> > >
> > > Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > > Signed-off-by: jason-jh.lin <jason-jh.lin@mediatek.com>
> > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > > ---
> > > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 20 ++++++++++++++++++--
> > > 1 file changed, 18 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > index e23e3224ac67..dad1f85ee315 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > @@ -54,6 +54,7 @@ struct mtk_drm_crtc {
> > > #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > > struct cmdq_client cmdq_client;
> > > u32 cmdq_event;
> > > + u32 cmdq_vblank_cnt;
> > > #endif
> > >
> > > struct device *mmsys_dev;
> > > @@ -227,7 +228,10 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
> > > static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> > > {
> > > struct cmdq_cb_data *data = mssg;
> > > + struct cmdq_client *cmdq_cl = container_of(cl, struct cmdq_client, client);
> > > + struct mtk_drm_crtc *mtk_crtc = container_of(cmdq_cl, struct mtk_drm_crtc, cmdq_client);
> > >
> > > + mtk_crtc->cmdq_vblank_cnt = 0;
> > > cmdq_pkt_destroy(data->pkt);
> > > }
> > > #endif
> > > @@ -483,6 +487,15 @@ static void mtk_drm_crtc_update_config(struct mtk_drm_crtc *mtk_crtc,
> > > cmdq_handle->pa_base,
> > > cmdq_handle->cmd_buf_size,
> > > DMA_TO_DEVICE);
> > > + /*
> > > + * CMDQ command should execute in next 3 vblank.
> > > + * One vblank interrupt before send message (occasionally)
> > > + * and one vblank interrupt after cmdq done,
> > > + * so it's timeout after 3 vblank interrupt.
> > > + * If it fail to execute in next 3 vblank, timeout happen.
> > > + */
> > > + mtk_crtc->cmdq_vblank_cnt = 3;
> > > +
> > > mbox_send_message(mtk_crtc->cmdq_client.chan, cmdq_handle);
> > > mbox_client_txdone(mtk_crtc->cmdq_client.chan, 0);
> > > }
> > > @@ -499,11 +512,14 @@ static void mtk_crtc_ddp_irq(void *data)
> > >
> > > #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > > if (!priv->data->shadow_register && !mtk_crtc->cmdq_client.chan)
> > > + mtk_crtc_ddp_config(crtc, NULL);
> > > + else if (mtk_crtc->cmdq_vblank_cnt > 0 && --mtk_crtc->cmdq_vblank_cnt == 0)
> > I think atomic_dec_and_test() does what you want to do here.
>
> I think this operation is not necessary to be atomic operation, and
> this statement could be reduced to
>
> else if (--mtk_crtc->cmdq_vblank_cnt == 0)
I was thinking about using existing helpers to wrap up the counter
operations, but I agree that it's not necessary.
Just dropping the redundant check would be good enough.
>
> >
> > > + DRM_ERROR("mtk_crtc %d CMDQ execute command timeout!\n",
> > > + drm_crtc_index(&mtk_crtc->base));
> > > #else
> > > if (!priv->data->shadow_register)
> > > -#endif
> > > mtk_crtc_ddp_config(crtc, NULL);
> > > -
> > > +#endif
> > > mtk_drm_finish_page_flip(mtk_crtc);
> > > }
> > >
> > > --
> > > 2.18.0
> > >
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v5 3/6] drm/mediatek: Detect CMDQ execution timeout
2021-10-28 3:19 ` Fei Shao
@ 2021-11-17 23:51 ` Chun-Kuang Hu
0 siblings, 0 replies; 6+ messages in thread
From: Chun-Kuang Hu @ 2021-11-17 23:51 UTC (permalink / raw)
To: Fei Shao
Cc: Chun-Kuang Hu, jason-jh.lin, Philipp Zabel, Matthias Brugger,
Jassi Brar, Yongqiang Niu, David Airlie, Daniel Vetter,
DRI Development, moderated list:ARM/Mediatek SoC support,
Linux ARM, linux-kernel, Hsin-Yi Wang, Nancy Lin, singo.chang
Hi, Fei:
Fei Shao <fshao@chromium.org> 於 2021年10月28日 週四 上午11:19寫道：
>
> Hi Chun-Kuang,
>
> On Thu, Oct 28, 2021 at 7:47 AM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote:
> >
> > Hi, Fei:
> >
> > Fei Shao <fshao@chromium.org> 於 2021年10月27日 週三 下午5:32寫道：
> > >
> > > Hi Jason,
> > >
> > > On Wed, Oct 27, 2021 at 10:19 AM jason-jh.lin <jason-jh.lin@mediatek.com> wrote:
> > > >
> > > > From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > > >
> > > > CMDQ is used to update display register in vblank period, so
> > > > it should be execute in next 2 vblank. One vblank interrupt
> > > > before send message (occasionally) and one vblank interrupt
> > > > after cmdq done. If it fail to execute in next 3 vblank,
> > > > tiemout happen.
> > > >
> > > > Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > > > Signed-off-by: jason-jh.lin <jason-jh.lin@mediatek.com>
> > > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
> > > > ---
> > > > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 20 ++++++++++++++++++--
> > > > 1 file changed, 18 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > > index e23e3224ac67..dad1f85ee315 100644
> > > > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > > @@ -54,6 +54,7 @@ struct mtk_drm_crtc {
> > > > #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > > > struct cmdq_client cmdq_client;
> > > > u32 cmdq_event;
> > > > + u32 cmdq_vblank_cnt;
> > > > #endif
> > > >
> > > > struct device *mmsys_dev;
> > > > @@ -227,7 +228,10 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
> > > > static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> > > > {
> > > > struct cmdq_cb_data *data = mssg;
> > > > + struct cmdq_client *cmdq_cl = container_of(cl, struct cmdq_client, client);
> > > > + struct mtk_drm_crtc *mtk_crtc = container_of(cmdq_cl, struct mtk_drm_crtc, cmdq_client);
> > > >
> > > > + mtk_crtc->cmdq_vblank_cnt = 0;
> > > > cmdq_pkt_destroy(data->pkt);
> > > > }
> > > > #endif
> > > > @@ -483,6 +487,15 @@ static void mtk_drm_crtc_update_config(struct mtk_drm_crtc *mtk_crtc,
> > > > cmdq_handle->pa_base,
> > > > cmdq_handle->cmd_buf_size,
> > > > DMA_TO_DEVICE);
> > > > + /*
> > > > + * CMDQ command should execute in next 3 vblank.
> > > > + * One vblank interrupt before send message (occasionally)
> > > > + * and one vblank interrupt after cmdq done,
> > > > + * so it's timeout after 3 vblank interrupt.
> > > > + * If it fail to execute in next 3 vblank, timeout happen.
> > > > + */
> > > > + mtk_crtc->cmdq_vblank_cnt = 3;
> > > > +
> > > > mbox_send_message(mtk_crtc->cmdq_client.chan, cmdq_handle);
> > > > mbox_client_txdone(mtk_crtc->cmdq_client.chan, 0);
> > > > }
> > > > @@ -499,11 +512,14 @@ static void mtk_crtc_ddp_irq(void *data)
> > > >
> > > > #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > > > if (!priv->data->shadow_register && !mtk_crtc->cmdq_client.chan)
> > > > + mtk_crtc_ddp_config(crtc, NULL);
> > > > + else if (mtk_crtc->cmdq_vblank_cnt > 0 && --mtk_crtc->cmdq_vblank_cnt == 0)
> > > I think atomic_dec_and_test() does what you want to do here.
> >
> > I think this operation is not necessary to be atomic operation, and
> > this statement could be reduced to
> >
> > else if (--mtk_crtc->cmdq_vblank_cnt == 0)
>
> I was thinking about using existing helpers to wrap up the counter
> operations, but I agree that it's not necessary.
> Just dropping the redundant check would be good enough.
I find one thing so that I would like this version. If we do not check
mtk_crtc->cmdq_vblank_cnt > 0, mtk_crtc->cmdq_vblank_cnt would
decrease to minus. And one day it would round to positive. So I would
pick this version instead of v6.
Regards,
Chun-Kuang.
>
>
> >
> > >
> > > > + DRM_ERROR("mtk_crtc %d CMDQ execute command timeout!\n",
> > > > + drm_crtc_index(&mtk_crtc->base));
> > > > #else
> > > > if (!priv->data->shadow_register)
> > > > -#endif
> > > > mtk_crtc_ddp_config(crtc, NULL);
> > > > -
> > > > +#endif
> > > > mtk_drm_finish_page_flip(mtk_crtc);
> > > > }
> > > >
> > > > --
> > > > 2.18.0
> > > >
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-11-17 23:51 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
[not found] <20211027021857.20816-1-jason-jh.lin@mediatek.com>
[not found] ` <20211027021857.20816-4-jason-jh.lin@mediatek.com>
2021-10-27 9:31 ` [PATCH v5 3/6] drm/mediatek: Detect CMDQ execution timeout Fei Shao
2021-10-27 23:47 ` Chun-Kuang Hu
2021-10-28 3:19 ` Fei Shao
2021-11-17 23:51 ` Chun-Kuang Hu
[not found] ` <20211027021857.20816-6-jason-jh.lin@mediatek.com>
2021-10-27 23:30 ` [PATCH v5 5/6] drm/mediatek: Add mbox_free_channel in mtk_drm_crtc_destroy Chun-Kuang Hu
[not found] ` <20211027021857.20816-5-jason-jh.lin@mediatek.com>
2021-10-27 23:32 ` [PATCH v5 4/6] drm/mediatek: Add cmdq_handle in mtk_crtc Chun-Kuang Hu
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).