RE: [PATCH v7 1/1] drm/bridge: it6505: fix hibernate to resume no display issue

From: kuro.chung
Date: Tue May 14 2024 - 05:13:46 EST




-----Original Message-----
From: Kuro Chung (鐘仕廷)
Sent: Tuesday, May 14, 2024 11:21 AM
To: 'Robert Foss' <rfoss@xxxxxxxxxx>
Cc: Allen Chen <allen.chen@xxxxxxxxxx>; Pin-yen Lin <treapking@xxxxxxxxxxxx>; Kenneth Hung (洪家倫) <Kenneth.Hung@xxxxxxxxxx>; Kuro Chung <kuro.chung@xxxxxxxxxxxxxxxxxxxxxxxxxxx>; Andrzej Hajda <andrzej.hajda@xxxxxxxxx>; Neil Armstrong <neil.armstrong@xxxxxxxxxx>; Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx>; Jonas Karlman <jonas@xxxxxxxxx>; Jernej Skrabec <jernej.skrabec@xxxxxxxxx>; Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>; Maxime Ripard <mripard@xxxxxxxxxx>; Thomas Zimmermann <tzimmermann@xxxxxxx>; David Airlie <airlied@xxxxxxxxx>; Daniel Vetter <daniel@xxxxxxxx>; open list:DRM DRIVERS <dri-devel@xxxxxxxxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx>
Subject: RE: [PATCH v7 1/1] drm/bridge: it6505: fix hibernate to resume no display issue

-----Original Message-----
From: Robert Foss <rfoss@xxxxxxxxxx>
Sent: Tuesday, May 14, 2024 1:45 AM
To: Kuro Chung (鐘仕廷) <kuro.chung@xxxxxxxxxx>
Cc: Allen Chen <allen.chen@xxxxxxxxxx>; Pin-yen Lin <treapking@xxxxxxxxxxxx>; Kenneth Hung (洪家倫) <Kenneth.Hung@xxxxxxxxxx>; Kuro Chung <kuro.chung@xxxxxxxxxxxxxxxxxxxxxxxxxxx>; Andrzej Hajda <andrzej.hajda@xxxxxxxxx>; Neil Armstrong <neil.armstrong@xxxxxxxxxx>; Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx>; Jonas Karlman <jonas@xxxxxxxxx>; Jernej Skrabec <jernej.skrabec@xxxxxxxxx>; Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>; Maxime Ripard <mripard@xxxxxxxxxx>; Thomas Zimmermann <tzimmermann@xxxxxxx>; David Airlie <airlied@xxxxxxxxx>; Daniel Vetter <daniel@xxxxxxxx>; open list:DRM DRIVERS <dri-devel@xxxxxxxxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx>
Subject: Re: [PATCH v7 1/1] drm/bridge: it6505: fix hibernate to resume no display issue

On Mon, May 13, 2024 at 7:42 PM Robert Foss <rfoss@xxxxxxxxxx> wrote:
>
> On Mon, May 6, 2024 at 11:36 AM kuro <kuro.chung@xxxxxxxxxx> wrote:
> >
> > From: Kuro <kuro.chung@xxxxxxxxxx>
> >
> > ITE added a FIFO reset bit for input video. When system power
> > resume, the TTL input of it6505 may get some noise before video
> > signal stable and the hardware function reset is required.
> > But the input FIFO reset will also trigger error interrupts of output module rising.
> > Thus, it6505 have to wait a period can clear those expected error
> > interrupts caused by manual hardware reset in one interrupt handler calling to avoid interrupt looping.
> >
> > Signed-off-by: Kuro Chung <kuro.chung@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
> >
> > ---
> > drivers/gpu/drm/bridge/ite-it6505.c | 73
> > +++++++++++++++++++----------
> > 1 file changed, 49 insertions(+), 24 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/ite-it6505.c
> > b/drivers/gpu/drm/bridge/ite-it6505.c
> > index b53da9bb65a16..64e2706e3d0c3 100644
> > --- a/drivers/gpu/drm/bridge/ite-it6505.c
> > +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> > @@ -1317,9 +1317,15 @@ static void it6505_video_reset(struct it6505 *it6505)
> > it6505_link_reset_step_train(it6505);
> > it6505_set_bits(it6505, REG_DATA_MUTE_CTRL, EN_VID_MUTE, EN_VID_MUTE);
> > it6505_set_bits(it6505, REG_INFOFRAME_CTRL, EN_VID_CTRL_PKT, 0x00);
> > - it6505_set_bits(it6505, REG_RESET_CTRL, VIDEO_RESET, VIDEO_RESET);
> > +
> > + it6505_set_bits(it6505, REG_VID_BUS_CTRL1, TX_FIFO_RESET, TX_FIFO_RESET);
> > + it6505_set_bits(it6505, REG_VID_BUS_CTRL1, TX_FIFO_RESET,
> > + 0x00);
> > +
> > it6505_set_bits(it6505, REG_501_FIFO_CTRL, RST_501_FIFO, RST_501_FIFO);
> > it6505_set_bits(it6505, REG_501_FIFO_CTRL, RST_501_FIFO,
> > 0x00);
> > +
> > + it6505_set_bits(it6505, REG_RESET_CTRL, VIDEO_RESET, VIDEO_RESET);
> > + usleep_range(1000, 2000);
> > it6505_set_bits(it6505, REG_RESET_CTRL, VIDEO_RESET, 0x00);
> > }
> >
> > @@ -2249,12 +2255,11 @@ static void it6505_link_training_work(struct work_struct *work)
> > if (ret) {
> > it6505->auto_train_retry = AUTO_TRAIN_RETRY;
> > it6505_link_train_ok(it6505);
> > - return;
> > } else {
> > it6505->auto_train_retry--;
> > + it6505_dump(it6505);
> > }
> >
> > - it6505_dump(it6505);
> > }
> >
> > static void it6505_plugged_status_to_codec(struct it6505 *it6505)
> > @@ -2475,31 +2480,53 @@ static void it6505_irq_link_train_fail(struct it6505 *it6505)
> > schedule_work(&it6505->link_works);
> > }
> >
> > -static void it6505_irq_video_fifo_error(struct it6505 *it6505)
> > +static bool it6505_test_bit(unsigned int bit, const unsigned int
> > +*addr)
> > {
> > - struct device *dev = &it6505->client->dev;
> > -
> > - DRM_DEV_DEBUG_DRIVER(dev, "video fifo overflow interrupt");
> > - it6505->auto_train_retry = AUTO_TRAIN_RETRY;
> > - flush_work(&it6505->link_works);
> > - it6505_stop_hdcp(it6505);
> > - it6505_video_reset(it6505);
> > + return 1 & (addr[bit / BITS_PER_BYTE] >> (bit %
> > + BITS_PER_BYTE));
> > }
> >
> > -static void it6505_irq_io_latch_fifo_overflow(struct it6505
> > *it6505)
> > +static void it6505_irq_video_handler(struct it6505 *it6505, const
> > +int *int_status)
> > {
> > struct device *dev = &it6505->client->dev;
> > + int reg_0d, reg_int03;
> >
> > - DRM_DEV_DEBUG_DRIVER(dev, "IO latch fifo overflow interrupt");
> > - it6505->auto_train_retry = AUTO_TRAIN_RETRY;
> > - flush_work(&it6505->link_works);
> > - it6505_stop_hdcp(it6505);
> > - it6505_video_reset(it6505);
> > -}
> > + /*
> > + * When video SCDT change with video not stable,
> > + * Or video FIFO error, need video reset
> > + */
> >
> > -static bool it6505_test_bit(unsigned int bit, const unsigned int
> > *addr) -{
> > - return 1 & (addr[bit / BITS_PER_BYTE] >> (bit % BITS_PER_BYTE));
> > + if ((!it6505_get_video_status(it6505) &&
> > + (it6505_test_bit(INT_SCDT_CHANGE, (unsigned int *) int_status))) ||
> > + (it6505_test_bit(BIT_INT_IO_FIFO_OVERFLOW, (unsigned int *) int_status)) ||
> > + (it6505_test_bit(BIT_INT_VID_FIFO_ERROR, (unsigned
> > + int *) int_status))) {
> > +
> > + it6505->auto_train_retry = AUTO_TRAIN_RETRY;
> > + flush_work(&it6505->link_works);
> > + it6505_stop_hdcp(it6505);
> > + it6505_video_reset(it6505);
> > +
> > + usleep_range(10000, 11000);
> > +
> > + /*
> > + * Clear FIFO error IRQ to prevent fifo error -> reset loop
> > + * HW will trigger SCDT change IRQ again when video stable
> > + */
> > +
> > + reg_int03 = it6505_read(it6505, INT_STATUS_03);
> > + reg_0d = it6505_read(it6505, REG_SYSTEM_STS);
> > +
> > + reg_int03 &= (BIT(INT_VID_FIFO_ERROR) | BIT(INT_IO_LATCH_FIFO_OVERFLOW));
> > + it6505_write(it6505, INT_STATUS_03, reg_int03);
> > +
> > + DRM_DEV_DEBUG_DRIVER(dev, "reg08 = 0x%02x", reg_int03);
> > + DRM_DEV_DEBUG_DRIVER(dev, "reg0D = 0x%02x", reg_0d);
> > +
> > + return;
> > + }
> > +
> > +
> > + if (it6505_test_bit(INT_SCDT_CHANGE, (unsigned int *) int_status))
> > + it6505_irq_scdt(it6505);
> > }
> >
> > static irqreturn_t it6505_int_threaded_handler(int unused, void
> > *data) @@ -2512,15 +2539,12 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
> > } irq_vec[] = {
> > { BIT_INT_HPD, it6505_irq_hpd },
> > { BIT_INT_HPD_IRQ, it6505_irq_hpd_irq },
> > - { BIT_INT_SCDT, it6505_irq_scdt },
> > { BIT_INT_HDCP_FAIL, it6505_irq_hdcp_fail },
> > { BIT_INT_HDCP_DONE, it6505_irq_hdcp_done },
> > { BIT_INT_AUX_CMD_FAIL, it6505_irq_aux_cmd_fail },
> > { BIT_INT_HDCP_KSV_CHECK, it6505_irq_hdcp_ksv_check },
> > { BIT_INT_AUDIO_FIFO_ERROR, it6505_irq_audio_fifo_error },
> > { BIT_INT_LINK_TRAIN_FAIL, it6505_irq_link_train_fail },
> > - { BIT_INT_VID_FIFO_ERROR, it6505_irq_video_fifo_error },
> > - { BIT_INT_IO_FIFO_OVERFLOW, it6505_irq_io_latch_fifo_overflow },
> > };
> > int int_status[3], i;
> >
> > @@ -2550,6 +2574,7 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
> > if (it6505_test_bit(irq_vec[i].bit, (unsigned int *)int_status))
> > irq_vec[i].handler(it6505);
> > }
> > + it6505_irq_video_handler(it6505, (unsigned int *)
> > + int_status);
> > }
> >
> > pm_runtime_put_sync(dev);
> > --
> > 2.25.1
> >
>
> Reviewed-by: Robert Foss <rfoss@xxxxxxxxxx>

This patch does not apply on drm-misc-next, please fix this and then this patch is ready to be applied.
-> It seems this patch conflict already, I will update a new one., thanks.

-> Hi Robert,
-> Excuse me, this is my first time to upload the patch, I'm afraid I'm
-> not following, would you mind be more specific or could I have a link or document for reference, Thank you.

->and I saw my tracked remote is drm-misc-next, does it anything wrong about upload the patch?
ite@ite-XPS-13-9360:~/project/it6505/google/source/cros/src/third_party/kernel/v5.15$ git remote show drm-misc
* remote drm-misc
Fetch URL: https://anongit.freedesktop.org/git/drm/drm-misc.git
Push URL: https://anongit.freedesktop.org/git/drm/drm-misc.git
HEAD branch: drm-misc-next
Remote branches:
drm-misc-fixes new (next fetch will store in remotes/drm-misc)
drm-misc-next tracked
drm-misc-next-fixes new (next fetch will store in remotes/drm-misc)
for-linux-next new (next fetch will store in remotes/drm-misc)
for-linux-next-fixes new (next fetch will store in remotes/drm-misc)
topic/rust-drm new (next fetch will store in remotes/drm-misc)