drm/i915/dp: do not limit rate seek when not needed

Submitted by Jani Nikula on March 29, 2017, 9:23 a.m.

Details

Message ID 1490779390-26535-1-git-send-email-jani.nikula@intel.com
State New
Headers show
Series "drm/i915/dp: link rate and lane count refactoring" ( rev: 4 ) in Intel GFX

Not browsing as part of any series.

Commit Message

Jani Nikula March 29, 2017, 9:23 a.m.
In link training fallback, we're trying to find a rate that we know is
in a sorted array of common link rates. We don't need to limit the array
using the max rate. For test request, the DP CTS doesn't say we should
limit the rate based on earlier fallback. This lets us get rid of
intel_dp_link_rate_index() and use intel_dp_rate_index() instead.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

---

updated commit message, no changes
---
 drivers/gpu/drm/i915/intel_dp.c | 31 ++++++++++++-------------------
 1 file changed, 12 insertions(+), 19 deletions(-)

Patch hide | download patch | download mbox

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 1808af6d635d..8c061c54d481 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -317,25 +317,16 @@  static int intel_dp_common_len_rate_limit(struct intel_dp *intel_dp,
 	return 0;
 }
 
-static int intel_dp_link_rate_index(struct intel_dp *intel_dp, int link_rate)
-{
-	int common_len;
-
-	common_len = intel_dp_common_len_rate_limit(intel_dp,
-						    intel_dp->max_sink_link_rate);
-
-	return intel_dp_rate_index(intel_dp->common_rates, common_len, link_rate);
-}
-
 int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp,
 					    int link_rate, uint8_t lane_count)
 {
-	const int *common_rates = intel_dp->common_rates;
-	int link_rate_index;
+	int index;
 
-	link_rate_index = intel_dp_link_rate_index(intel_dp, link_rate);
-	if (link_rate_index > 0) {
-		intel_dp->max_sink_link_rate = common_rates[link_rate_index - 1];
+	index = intel_dp_rate_index(intel_dp->common_rates,
+				    intel_dp->num_common_rates,
+				    link_rate);
+	if (index > 0) {
+		intel_dp->max_sink_link_rate = intel_dp->common_rates[index - 1];
 		intel_dp->max_sink_lane_count = lane_count;
 	} else if (lane_count > 1) {
 		intel_dp->max_sink_link_rate = intel_dp_max_sink_rate(intel_dp);
@@ -1685,8 +1676,9 @@  intel_dp_compute_config(struct intel_encoder *encoder,
 
 	/* Use values requested by Compliance Test Request */
 	if (intel_dp->compliance.test_type == DP_TEST_LINK_TRAINING) {
-		link_rate_index = intel_dp_link_rate_index(intel_dp,
-							   intel_dp->compliance.test_link_rate);
+		link_rate_index = intel_dp_rate_index(intel_dp->common_rates,
+						      intel_dp->num_common_rates,
+						      intel_dp->compliance.test_link_rate);
 		if (link_rate_index >= 0)
 			min_clock = max_clock = link_rate_index;
 		min_lane_count = max_lane_count = intel_dp->compliance.test_lane_count;
@@ -3988,8 +3980,9 @@  static uint8_t intel_dp_autotest_link_training(struct intel_dp *intel_dp)
 	}
 	/* Validate the requested link rate */
 	test_link_rate = drm_dp_bw_code_to_link_rate(test_link_bw);
-	link_rate_index = intel_dp_link_rate_index(intel_dp,
-						   test_link_rate);
+	link_rate_index = intel_dp_rate_index(intel_dp->common_rates,
+					      intel_dp->num_common_rates,
+					      test_link_rate);
 	if (link_rate_index < 0)
 		return DP_TEST_NAK;
 

Comments

The commit message looks good now.

Reviewed-by: <manasi.d.navare@intel.com>

Manasi

On Wed, Mar 29, 2017 at 12:23:10PM +0300, Jani Nikula wrote:
> In link training fallback, we're trying to find a rate that we know is
> in a sorted array of common link rates. We don't need to limit the array
> using the max rate. For test request, the DP CTS doesn't say we should
> limit the rate based on earlier fallback. This lets us get rid of
> intel_dp_link_rate_index() and use intel_dp_rate_index() instead.
> 
> Cc: Manasi Navare <manasi.d.navare@intel.com>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> 
> ---
> 
> updated commit message, no changes
> ---
>  drivers/gpu/drm/i915/intel_dp.c | 31 ++++++++++++-------------------
>  1 file changed, 12 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 1808af6d635d..8c061c54d481 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -317,25 +317,16 @@ static int intel_dp_common_len_rate_limit(struct intel_dp *intel_dp,
>  	return 0;
>  }
>  
> -static int intel_dp_link_rate_index(struct intel_dp *intel_dp, int link_rate)
> -{
> -	int common_len;
> -
> -	common_len = intel_dp_common_len_rate_limit(intel_dp,
> -						    intel_dp->max_sink_link_rate);
> -
> -	return intel_dp_rate_index(intel_dp->common_rates, common_len, link_rate);
> -}
> -
>  int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp,
>  					    int link_rate, uint8_t lane_count)
>  {
> -	const int *common_rates = intel_dp->common_rates;
> -	int link_rate_index;
> +	int index;
>  
> -	link_rate_index = intel_dp_link_rate_index(intel_dp, link_rate);
> -	if (link_rate_index > 0) {
> -		intel_dp->max_sink_link_rate = common_rates[link_rate_index - 1];
> +	index = intel_dp_rate_index(intel_dp->common_rates,
> +				    intel_dp->num_common_rates,
> +				    link_rate);
> +	if (index > 0) {
> +		intel_dp->max_sink_link_rate = intel_dp->common_rates[index - 1];
>  		intel_dp->max_sink_lane_count = lane_count;
>  	} else if (lane_count > 1) {
>  		intel_dp->max_sink_link_rate = intel_dp_max_sink_rate(intel_dp);
> @@ -1685,8 +1676,9 @@ intel_dp_compute_config(struct intel_encoder *encoder,
>  
>  	/* Use values requested by Compliance Test Request */
>  	if (intel_dp->compliance.test_type == DP_TEST_LINK_TRAINING) {
> -		link_rate_index = intel_dp_link_rate_index(intel_dp,
> -							   intel_dp->compliance.test_link_rate);
> +		link_rate_index = intel_dp_rate_index(intel_dp->common_rates,
> +						      intel_dp->num_common_rates,
> +						      intel_dp->compliance.test_link_rate);
>  		if (link_rate_index >= 0)
>  			min_clock = max_clock = link_rate_index;
>  		min_lane_count = max_lane_count = intel_dp->compliance.test_lane_count;
> @@ -3988,8 +3980,9 @@ static uint8_t intel_dp_autotest_link_training(struct intel_dp *intel_dp)
>  	}
>  	/* Validate the requested link rate */
>  	test_link_rate = drm_dp_bw_code_to_link_rate(test_link_bw);
> -	link_rate_index = intel_dp_link_rate_index(intel_dp,
> -						   test_link_rate);
> +	link_rate_index = intel_dp_rate_index(intel_dp->common_rates,
> +					      intel_dp->num_common_rates,
> +					      test_link_rate);
>  	if (link_rate_index < 0)
>  		return DP_TEST_NAK;
>  
> -- 
> 2.1.4
>