Re: [PATCH v5 26/36] drm/bridge: analogix_dp: Properly disable aux chan retries on rockchip

[Archit Taneja]

On Saturday 10 March 2018 03:53 AM, Enric Balletbo i Serra wrote:

From: Douglas Anderson 

The comments in analogix_dp_init_aux() claim that we're disabling aux
channel retries, but then right below it for Rockchip it sets them to
3.  If we actually need 3 retries for Rockchip then we could adjust
the comment, but it seems more likely that we want the same retry
behavior across all platforms.


Reviewed-by: Archit Taneja 

Thanks,
Archit



Cc: Stéphane Marchesin 
Cc: 征增 王 
Signed-off-by: Douglas Anderson 
Signed-off-by: Sean Paul 
Signed-off-by: Thierry Escande 
Signed-off-by: Enric Balletbo i Serra 
Tested-by: Marek Szyprowski 
---

  drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 15 ---
  1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c 
b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
index 58e8a28e99aa..a5f2763d72e4 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
@@ -481,15 +481,16 @@ void analogix_dp_init_aux(struct analogix_dp_device *dp)
  
  	analogix_dp_reset_aux(dp);
  
-	/* Disable AUX transaction H/W retry */

+   /* AUX_BIT_PERIOD_EXPECTED_DELAY doesn't apply to Rockchip IP */
if (dp->plat_data && is_rockchip(dp->plat_data->dev_type))
-   reg = AUX_BIT_PERIOD_EXPECTED_DELAY(0) |
- AUX_HW_RETRY_COUNT_SEL(3) |
- AUX_HW_RETRY_INTERVAL_600_MICROSECONDS;
+   reg = 0;
else
-   reg = AUX_BIT_PERIOD_EXPECTED_DELAY(3) |
- AUX_HW_RETRY_COUNT_SEL(0) |
- AUX_HW_RETRY_INTERVAL_600_MICROSECONDS;
+   reg = AUX_BIT_PERIOD_EXPECTED_DELAY(3);
+
+   /* Disable AUX transaction H/W retry */
+   reg |= AUX_HW_RETRY_COUNT_SEL(0) |
+  AUX_HW_RETRY_INTERVAL_600_MICROSECONDS;
+
writel(reg, dp->reg_base + ANALOGIX_DP_AUX_HW_RETRY_CTL);
  
  	/* Receive AUX Channel DEFER commands equal to DEFFER_COUNT*64 */

Re: [PATCH v5 26/36] drm/bridge: analogix_dp: Properly disable aux chan retries on rockchip

[Archit Taneja]

On Saturday 10 March 2018 03:53 AM, Enric Balletbo i Serra wrote:

From: Douglas Anderson 

The comments in analogix_dp_init_aux() claim that we're disabling aux
channel retries, but then right below it for Rockchip it sets them to
3.  If we actually need 3 retries for Rockchip then we could adjust
the comment, but it seems more likely that we want the same retry
behavior across all platforms.


Reviewed-by: Archit Taneja 

Thanks,
Archit



Cc: Stéphane Marchesin 
Cc: 征增 王 
Signed-off-by: Douglas Anderson 
Signed-off-by: Sean Paul 
Signed-off-by: Thierry Escande 
Signed-off-by: Enric Balletbo i Serra 
Tested-by: Marek Szyprowski 
---

  drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 15 ---
  1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c 
b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
index 58e8a28e99aa..a5f2763d72e4 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
@@ -481,15 +481,16 @@ void analogix_dp_init_aux(struct analogix_dp_device *dp)
  
  	analogix_dp_reset_aux(dp);
  
-	/* Disable AUX transaction H/W retry */

+   /* AUX_BIT_PERIOD_EXPECTED_DELAY doesn't apply to Rockchip IP */
if (dp->plat_data && is_rockchip(dp->plat_data->dev_type))
-   reg = AUX_BIT_PERIOD_EXPECTED_DELAY(0) |
- AUX_HW_RETRY_COUNT_SEL(3) |
- AUX_HW_RETRY_INTERVAL_600_MICROSECONDS;
+   reg = 0;
else
-   reg = AUX_BIT_PERIOD_EXPECTED_DELAY(3) |
- AUX_HW_RETRY_COUNT_SEL(0) |
- AUX_HW_RETRY_INTERVAL_600_MICROSECONDS;
+   reg = AUX_BIT_PERIOD_EXPECTED_DELAY(3);
+
+   /* Disable AUX transaction H/W retry */
+   reg |= AUX_HW_RETRY_COUNT_SEL(0) |
+  AUX_HW_RETRY_INTERVAL_600_MICROSECONDS;
+
writel(reg, dp->reg_base + ANALOGIX_DP_AUX_HW_RETRY_CTL);
  
  	/* Receive AUX Channel DEFER commands equal to DEFFER_COUNT*64 */