[PATCH 13/14] drm/i915: Use intel_dp->DP in eDP PLL setup

ville.syrjala
2015-10-29T19:26:48Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Use intel_dp->DP in the eDP PLL setup, instead of doing RMWs.

To do this we need to move DP_AUDIO_OUTPUT_ENABLE setup to happen later,
so that we don't enable audio accidentally while configuring the PLL.

Also intel_dp_link_down() must be made to update intel_dp->DP so that we
don't re-enable the port by accident when turning off the PLL. This is
safe now that we don't call intel_dp_link_down() during link retraining.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
drivers/gpu/drm/i915/intel_dp.c | 41 ++++++++++++++---------------------------
1 file changed, 14 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index e259803..63659e7 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1548,23 +1548,18 @@ static void ironlake_set_pll_cpu_edp(struct intel_dp *intel_dp)
struct intel_crtc *crtc = to_intel_crtc(dig_port->base.base.crtc);
struct drm_device *dev = crtc->base.dev;
struct drm_i915_private *dev_priv = dev->dev_private;
- u32 dpa_ctl;

DRM_DEBUG_KMS("eDP PLL enable for clock %d\n",
crtc->config->port_clock);
- dpa_ctl = I915_READ(DP_A);
- dpa_ctl &= ~DP_PLL_FREQ_MASK;

- if (crtc->config->port_clock == 162000) {
- dpa_ctl |= DP_PLL_FREQ_162MHZ;
+ intel_dp->DP &= ~DP_PLL_FREQ_MASK;
+
+ if (crtc->config->port_clock == 162000)
intel_dp->DP |= DP_PLL_FREQ_162MHZ;
- } else {
- dpa_ctl |= DP_PLL_FREQ_270MHZ;
+ else
intel_dp->DP |= DP_PLL_FREQ_270MHZ;
- }
-
- I915_WRITE(DP_A, dpa_ctl);

+ I915_WRITE(DP_A, intel_dp->DP);
POSTING_READ(DP_A);
udelay(500);
}
@@ -1613,9 +1608,6 @@ static void intel_dp_prepare(struct intel_encoder *encoder)
intel_dp->DP |= DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0;
intel_dp->DP |= DP_PORT_WIDTH(crtc->config->lane_count);

- if (crtc->config->has_audio)
- intel_dp->DP |= DP_AUDIO_OUTPUT_ENABLE;
-
/* Split out the IBX/CPU vs CPT settings */

if (IS_GEN7(dev) && port == PORT_A) {
@@ -2176,20 +2168,14 @@ static void ironlake_edp_pll_on(struct intel_dp *intel_dp)
struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
struct intel_crtc *crtc = to_intel_crtc(intel_dig_port->base.base.crtc);
struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
- u32 dpa_ctl;

assert_pipe_disabled(dev_priv, crtc->pipe);
assert_dp_port_disabled(intel_dp);
assert_edp_pll_disabled(dev_priv);

DRM_DEBUG_KMS("\n");
- dpa_ctl = I915_READ(DP_A);
-
- /* We don't adjust intel_dp->DP while tearing down the link, to
- * facilitate link retraining (e.g. after hotplug). Hence clear all
- * enable bits here to ensure that we don't enable too much. */
- intel_dp->DP &= ~(DP_PORT_EN | DP_AUDIO_OUTPUT_ENABLE);
intel_dp->DP |= DP_PLL_ENABLE;
+
I915_WRITE(DP_A, intel_dp->DP);
POSTING_READ(DP_A);
udelay(200);
@@ -2200,19 +2186,14 @@ static void ironlake_edp_pll_off(struct intel_dp *intel_dp)
struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
struct intel_crtc *crtc = to_intel_crtc(intel_dig_port->base.base.crtc);
struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
- u32 dpa_ctl;

assert_pipe_disabled(dev_priv, crtc->pipe);
assert_dp_port_disabled(intel_dp);
assert_edp_pll_enabled(dev_priv);

- dpa_ctl = I915_READ(DP_A);
+ intel_dp->DP &= ~DP_PLL_ENABLE;

- /* We can't rely on the value tracked for the DP register in
- * intel_dp->DP because link_down must not change that (otherwise link
- * re-training will fail. */
- dpa_ctl &= ~DP_PLL_ENABLE;
- I915_WRITE(DP_A, dpa_ctl);
+ I915_WRITE(DP_A, intel_dp->DP);
POSTING_READ(DP_A);
udelay(200);
}
@@ -2568,6 +2549,8 @@ static void intel_dp_enable_port(struct intel_dp *intel_dp)
{
struct drm_device *dev = intel_dp_to_dev(intel_dp);
struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc *crtc =
+ to_intel_crtc(dp_to_dig_port(intel_dp)->base.base.crtc);

/* enable with pattern 1 (as per spec) */
_intel_dp_set_link_train(intel_dp, &intel_dp->DP,
@@ -2583,6 +2566,8 @@ static void intel_dp_enable_port(struct intel_dp *intel_dp)
* fail when the power sequencer is freshly used for this port.
*/
intel_dp->DP |= DP_PORT_EN;
+ if (crtc->config->has_audio)
+ intel_dp->DP |= DP_AUDIO_OUTPUT_ENABLE;

I915_WRITE(intel_dp->output_reg, intel_dp->DP);
POSTING_READ(intel_dp->output_reg);
@@ -4028,6 +4013,8 @@ intel_dp_link_down(struct intel_dp *intel_dp)
}

msleep(intel_dp->panel_power_down_delay);
+
+ intel_dp->DP = DP;
}

static bool
--
2.4.10