Re: [PATCH] soc: mediatek: cmdq: Remove timeout handler in helper function

From: Chun-Kuang Hu
Date: Mon Sep 21 2020 - 11:33:03 EST


Hi, Matthias:

Matthias Brugger <matthias.bgg@xxxxxxxxx> 於 2020年9月21日 週一 下午4:53寫道:
>
>
>
> On 21/09/2020 01:42, Chun-Kuang Hu wrote:
> > For each client driver, its timeout handler need to dump hardware register
> > or its state machine information, so remove timeout handler in helper
> > function and let client driver implement its own timeout handler.
> >
>
> I don't see the implementation of a client side handler. Did I miss something?
> Would it make sense to instead add a callback to the handler in cmdq_mbox_create()?

According to the commit message, it make sense to add a callback to
the handler in comq_mbox_create().
But for DRM, I would like to check timeout in vblank irq because the
register should be applied in vblank. (I have not implement this patch
yet)
What I want to say is that different client may have different way to
detect timeout and different way to handle it.
If you want, I would add DRM timeout handle patch with this patch, and
modify commit message to include different way to detect timeout.

Regards,
Chun-Kuang.

>
> Regards,
> Matthias
>
> > Signed-off-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
> > ---
> > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 3 +-
> > drivers/soc/mediatek/mtk-cmdq-helper.c | 41 +------------------------
> > include/linux/soc/mediatek/mtk-cmdq.h | 11 +------
> > 3 files changed, 3 insertions(+), 52 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > index 3fc5511330b9..cabeb7fea2be 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > @@ -824,8 +824,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> > #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> > mtk_crtc->cmdq_client =
> > cmdq_mbox_create(mtk_crtc->mmsys_dev,
> > - drm_crtc_index(&mtk_crtc->base),
> > - 2000);
> > + drm_crtc_index(&mtk_crtc->base));
> > if (IS_ERR(mtk_crtc->cmdq_client)) {
> > dev_dbg(dev, "mtk_crtc %d failed to create mailbox client, writing register by CPU now\n",
> > drm_crtc_index(&mtk_crtc->base));
> > diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
> > index dc644cfb6419..4f311f035b59 100644
> > --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> > +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> > @@ -65,14 +65,7 @@ int cmdq_dev_get_client_reg(struct device *dev,
> > }
> > EXPORT_SYMBOL(cmdq_dev_get_client_reg);
> >
> > -static void cmdq_client_timeout(struct timer_list *t)
> > -{
> > - struct cmdq_client *client = from_timer(client, t, timer);
> > -
> > - dev_err(client->client.dev, "cmdq timeout!\n");
> > -}
> > -
> > -struct cmdq_client *cmdq_mbox_create(struct device *dev, int index, u32 timeout)
> > +struct cmdq_client *cmdq_mbox_create(struct device *dev, int index)
> > {
> > struct cmdq_client *client;
> >
> > @@ -80,12 +73,6 @@ struct cmdq_client *cmdq_mbox_create(struct device *dev, int index, u32 timeout)
> > if (!client)
> > return (struct cmdq_client *)-ENOMEM;
> >
> > - client->timeout_ms = timeout;
> > - if (timeout != CMDQ_NO_TIMEOUT) {
> > - spin_lock_init(&client->lock);
> > - timer_setup(&client->timer, cmdq_client_timeout, 0);
> > - }
> > - client->pkt_cnt = 0;
> > client->client.dev = dev;
> > client->client.tx_block = false;
> > client->client.knows_txdone = true;
> > @@ -107,11 +94,6 @@ EXPORT_SYMBOL(cmdq_mbox_create);
> >
> > void cmdq_mbox_destroy(struct cmdq_client *client)
> > {
> > - if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
> > - spin_lock(&client->lock);
> > - del_timer_sync(&client->timer);
> > - spin_unlock(&client->lock);
> > - }
> > mbox_free_channel(client->chan);
> > kfree(client);
> > }
> > @@ -342,18 +324,6 @@ static void cmdq_pkt_flush_async_cb(struct cmdq_cb_data data)
> > struct cmdq_task_cb *cb = &pkt->cb;
> > struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
> >
> > - if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
> > - unsigned long flags = 0;
> > -
> > - spin_lock_irqsave(&client->lock, flags);
> > - if (--client->pkt_cnt == 0)
> > - del_timer(&client->timer);
> > - else
> > - mod_timer(&client->timer, jiffies +
> > - msecs_to_jiffies(client->timeout_ms));
> > - spin_unlock_irqrestore(&client->lock, flags);
> > - }
> > -
> > dma_sync_single_for_cpu(client->chan->mbox->dev, pkt->pa_base,
> > pkt->cmd_buf_size, DMA_TO_DEVICE);
> > if (cb->cb) {
> > @@ -366,7 +336,6 @@ int cmdq_pkt_flush_async(struct cmdq_pkt *pkt, cmdq_async_flush_cb cb,
> > void *data)
> > {
> > int err;
> > - unsigned long flags = 0;
> > struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
> >
> > pkt->cb.cb = cb;
> > @@ -377,14 +346,6 @@ int cmdq_pkt_flush_async(struct cmdq_pkt *pkt, cmdq_async_flush_cb cb,
> > dma_sync_single_for_device(client->chan->mbox->dev, pkt->pa_base,
> > pkt->cmd_buf_size, DMA_TO_DEVICE);
> >
> > - if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
> > - spin_lock_irqsave(&client->lock, flags);
> > - if (client->pkt_cnt++ == 0)
> > - mod_timer(&client->timer, jiffies +
> > - msecs_to_jiffies(client->timeout_ms));
> > - spin_unlock_irqrestore(&client->lock, flags);
> > - }
> > -
> > err = mbox_send_message(client->chan, pkt);
> > if (err < 0)
> > return err;
> > diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
> > index 2249ecaf77e4..175bd89f46f8 100644
> > --- a/include/linux/soc/mediatek/mtk-cmdq.h
> > +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> > @@ -11,8 +11,6 @@
> > #include <linux/mailbox/mtk-cmdq-mailbox.h>
> > #include <linux/timer.h>
> >
> > -#define CMDQ_NO_TIMEOUT 0xffffffffu
> > -
> > struct cmdq_pkt;
> >
> > struct cmdq_client_reg {
> > @@ -22,12 +20,8 @@ struct cmdq_client_reg {
> > };
> >
> > struct cmdq_client {
> > - spinlock_t lock;
> > - u32 pkt_cnt;
> > struct mbox_client client;
> > struct mbox_chan *chan;
> > - struct timer_list timer;
> > - u32 timeout_ms; /* in unit of microsecond */
> > };
> >
> > /**
> > @@ -49,13 +43,10 @@ int cmdq_dev_get_client_reg(struct device *dev,
> > * cmdq_mbox_create() - create CMDQ mailbox client and channel
> > * @dev: device of CMDQ mailbox client
> > * @index: index of CMDQ mailbox channel
> > - * @timeout: timeout of a pkt execution by GCE, in unit of microsecond, set
> > - * CMDQ_NO_TIMEOUT if a timer is not used.
> > *
> > * Return: CMDQ mailbox client pointer
> > */
> > -struct cmdq_client *cmdq_mbox_create(struct device *dev, int index,
> > - u32 timeout);
> > +struct cmdq_client *cmdq_mbox_create(struct device *dev, int index);
> >
> > /**
> > * cmdq_mbox_destroy() - destroy CMDQ mailbox client and channel
> >