Re: [PATCH v2 2/2] drm/bridge: analogix_dp: detect Sink PSR state after configuring the PSR

On 09/08/2016 10:12 PM, Sean Paul wrote:

On Wed, Sep 7, 2016 at 11:48 PM, Yakir Yang ykk@rock-chips.com wrote:

...

Make sure the request PSR state could effect in analogix_dp_send_psr_spd() function, or printing the error Sink PSR state if we failed to effect the request PSR setting.

Let's change to:

Make sure the request PSR state takes effect in analogix_dp_send_psr_spd() function, or print the sink PSR error state if we failed to apply the requested PSR setting.

Done,

...

Signed-off-by: Yakir Yang ykk@rock-chips.com

Changes in v2:

• A bunch of good fixes from Sean

  drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 6 ++---- drivers/gpu/drm/bridge/analogix/analogix_dp_core.h | 4 ++-- drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 25 ++++++++++++++++++++-- 3 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c index 5fe3982..c0ce16a 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c @@ -116,8 +116,7 @@ int analogix_dp_enable_psr(struct device *dev) psr_vsc.DB0 = 0; psr_vsc.DB1 = EDP_VSC_PSR_STATE_ACTIVE | EDP_VSC_PSR_CRC_VALUES_VALID;

•   analogix_dp_send_psr_spd(dp, &psr_vsc);
  

•   return 0;
  

•   return analogix_dp_send_psr_spd(dp, &psr_vsc);
  

  } EXPORT_SYMBOL_GPL(analogix_dp_enable_psr);

@@ -139,8 +138,7 @@ int analogix_dp_disable_psr(struct device *dev) psr_vsc.DB0 = 0; psr_vsc.DB1 = 0;

•   analogix_dp_send_psr_spd(dp, &psr_vsc);
  

•   return 0;
  

•   return analogix_dp_send_psr_spd(dp, &psr_vsc);
  

  } EXPORT_SYMBOL_GPL(analogix_dp_disable_psr);

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h index a15f076..6c07a50 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h @@ -247,8 +247,8 @@ void analogix_dp_config_video_slave_mode(struct analogix_dp_device *dp); void analogix_dp_enable_scrambling(struct analogix_dp_device *dp); void analogix_dp_disable_scrambling(struct analogix_dp_device *dp); void analogix_dp_enable_psr_crc(struct analogix_dp_device *dp); -void analogix_dp_send_psr_spd(struct analogix_dp_device *dp,

•                         struct edp_vsc_psr *vsc);
  

+int analogix_dp_send_psr_spd(struct analogix_dp_device *dp,

•                        struct edp_vsc_psr *vsc);
  

  ssize_t analogix_dp_transfer(struct analogix_dp_device *dp, struct drm_dp_aux_msg *msg); #endif /* _ANALOGIX_DP_CORE_H */

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c index a4d17b8..09d703b 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c @@ -1004,10 +1004,12 @@ void analogix_dp_enable_psr_crc(struct analogix_dp_device *dp) writel(PSR_VID_CRC_ENABLE, dp->reg_base + ANALOGIX_DP_CRC_CON); }

-void analogix_dp_send_psr_spd(struct analogix_dp_device *dp,

•                         struct edp_vsc_psr *vsc)
  

+int analogix_dp_send_psr_spd(struct analogix_dp_device *dp,

•                        struct edp_vsc_psr *vsc)
  

  {

•   unsigned long timeout;
     unsigned int val;
  

•   u8 sink;
  
     /* don't send info frame */
     val = readl(dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
  

@@ -1048,6 +1050,25 @@ void analogix_dp_send_psr_spd(struct analogix_dp_device *dp, val = readl(dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL); val |= IF_EN; writel(val, dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);

•   timeout = jiffies + msecs_to_jiffies(DP_TIMEOUT_LOOP_COUNT);
  

Mismatched units here. DP_TIMEOUT_LOOP_COUNT is defined as number of retries, whereas you're using it as number of ms. Fortunately, the retry number is so high that this works out :)

In a separate patch preceding this one, can you change DP_TIMEOUT_LOOP_COUNT to DP_TIMEOUT_LOOP_MS and alter the other timeout loops to use time_before() like this one instead of blindly looping 100 times? After that, you can use DP_TIMEOUT_LOOP_MS here.

Done, and after do some experiments, I found we need to set the timeout to 300ms. Cause in some case we would take about 290ms here to get the right psr state.

...

•   while (time_before(jiffies, timeout)) {
  

•           val = drm_dp_dpcd_readb(&dp->aux, DP_PSR_STATUS, &sink);
  

•           if (val != 1) {
  

•                   dev_err(dp->dev, "PSR_STATUS read failed ret=%d", val);
  

•                   return val;
  

Ok, since this is my snippet this comment is my fault, and I apologize for that :). However, this could return 0. If drm_dp_dpcd_readb returns 0, you probably want to retry (same as -EBUSY).

done, just return -EBUSY

...

•           }
  

•           if (vsc->DB1 && sink == DP_PSR_SINK_ACTIVE_RFB ||
  

•               !vsc->DB1 && sink == DP_PSR_SINK_INACTIVE)
  

•                   break;
  

•           usleep_range(1000, 1500);
  

•   }
  

•   dev_warn(dp->dev, "Failed to effect PSR: %x", sink);
  

Nit: I think you want to say "PSR failed to take effect" or "Failed to apply PSR"

Done

- Yakir

Sean

...

•   return -ETIMEDOUT;
  

  }

  ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,

-- 1.9.1

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