Re: [PATCH 04/22] drm/i915: Move register write into intel_dp_set_signal_levels()

Thulasimani, Sivakumar
2015-10-25T02:28:27Z

Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>

On 10/23/2015 3:31 PM, Ander Conselvan de Oliveira wrote:
> Move register write from intel_dp_update_link_train() into
> intel_dp_set_signal_levels(). This creates a better split between the
> i915 specific code and the generic link training part. Note that this
> causes an extra register write in intel_dp_reset_link_train(), since
> both intel_dp_set_signal_levels() and intel_dp_set_link_train() write
> to the DP register.
>
> Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
> ---
> drivers/gpu/drm/i915/intel_dp.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 11f2385..4ffb2e3 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -3550,13 +3550,13 @@ gen7_edp_signal_levels(uint8_t train_set)
> }
> }
>
> -/* Properly updates "DP" with the correct signal levels. */
> static void
> intel_dp_set_signal_levels(struct intel_dp *intel_dp)
> {
> struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
> enum port port = intel_dig_port->port;
> struct drm_device *dev = intel_dig_port->base.base.dev;
> + struct drm_i915_private *dev_priv = to_i915(dev);
> uint32_t signal_levels, mask = 0;
> uint8_t train_set = intel_dp->train_set[0];
>
> @@ -3592,6 +3592,9 @@ intel_dp_set_signal_levels(struct intel_dp *intel_dp)
> DP_TRAIN_PRE_EMPHASIS_SHIFT);
>
> intel_dp->DP = (intel_dp->DP & ~mask) | signal_levels;
> +
> + I915_WRITE(intel_dp->output_reg, intel_dp->DP);
> + POSTING_READ(intel_dp->output_reg);
> }
>
> static void
> @@ -3647,16 +3650,10 @@ intel_dp_reset_link_train(struct intel_dp *intel_dp,
> static bool
> intel_dp_update_link_train(struct intel_dp *intel_dp)
> {
> - struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
> - struct drm_i915_private *dev_priv =
> - to_i915(intel_dig_port->base.base.dev);
> int ret;
>
> intel_dp_set_signal_levels(intel_dp);
>
> - I915_WRITE(intel_dp->output_reg, intel_dp->DP);
> - POSTING_READ(intel_dp->output_reg);
> -
> ret = drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_LANE0_SET,
> intel_dp->train_set, intel_dp->lane_count);
>