drm/i915: do full backlight setup at enable time

We should now have all the information we need to do a full
initialization of the backlight registers.

v2: Keep QUIRK_NO_PCH_PWM_ENABLE for now (Imre).

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 93 insertions, 56 deletions

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 0e8f0a3d3bf6..0986472d4254 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -719,50 +719,75 @@ static void pch_enable_backlight(struct intel_connector *connector)
         enum pipe pipe = intel_get_pipe_from_connector(connector);
         enum transcoder cpu_transcoder =
                 intel_pipe_to_cpu_transcoder(dev_priv, pipe);
-        u32 tmp;
-
-        tmp = I915_READ(BLC_PWM_CPU_CTL2);
+        u32 cpu_ctl2, pch_ctl1, pch_ctl2;
 
-        /* Note that this can also get called through dpms changes. And
-         * we don't track the backlight dpms state, hence check whether
-         * we have to do anything first. */
-        if (tmp & BLM_PWM_ENABLE)
-                return;
+        cpu_ctl2 = I915_READ(BLC_PWM_CPU_CTL2);
+        if (cpu_ctl2 & BLM_PWM_ENABLE) {
+                WARN(1, "cpu backlight already enabled\n");
+                cpu_ctl2 &= ~BLM_PWM_ENABLE;
+                I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
+        }
 
-        if (INTEL_INFO(dev)->num_pipes == 3)
-                tmp &= ~BLM_PIPE_SELECT_IVB;
-        else
-                tmp &= ~BLM_PIPE_SELECT;
+        pch_ctl1 = I915_READ(BLC_PWM_PCH_CTL1);
+        if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
+                DRM_DEBUG_KMS("pch backlight already enabled\n");
+                pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
+                I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
+        }
 
         if (cpu_transcoder == TRANSCODER_EDP)
-                tmp |= BLM_TRANSCODER_EDP;
+                cpu_ctl2 = BLM_TRANSCODER_EDP;
         else
-                tmp |= BLM_PIPE(cpu_transcoder);
-        tmp &= ~BLM_PWM_ENABLE;
-
-        I915_WRITE(BLC_PWM_CPU_CTL2, tmp);
+                cpu_ctl2 = BLM_PIPE(cpu_transcoder);
+        I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2);
         POSTING_READ(BLC_PWM_CPU_CTL2);
-        I915_WRITE(BLC_PWM_CPU_CTL2, tmp | BLM_PWM_ENABLE);
-
-        if (!(dev_priv->quirks & QUIRK_NO_PCH_PWM_ENABLE)) {
-                tmp = I915_READ(BLC_PWM_PCH_CTL1);
-                tmp |= BLM_PCH_PWM_ENABLE;
-                tmp &= ~BLM_PCH_OVERRIDE_ENABLE;
-                I915_WRITE(BLC_PWM_PCH_CTL1, tmp);
-        }
+        I915_WRITE(BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
 
-        /*
-         * Call below after setting BLC_PWM_CPU_CTL2 and BLC_PWM_PCH_CTL1.
-         * BLC_PWM_CPU_CTL may be cleared to zero automatically when these
-         * registers are set.
-         */
+        /* This won't stick until the above enable. */
         intel_panel_actually_set_backlight(connector, panel->backlight.level);
+
+        pch_ctl2 = panel->backlight.max << 16;
+        I915_WRITE(BLC_PWM_PCH_CTL2, pch_ctl2);
+
+        /* XXX: transitional */
+        if (dev_priv->quirks & QUIRK_NO_PCH_PWM_ENABLE)
+                return;
+
+        pch_ctl1 = 0;
+        if (panel->backlight.active_low_pwm)
+                pch_ctl1 |= BLM_PCH_POLARITY;
+        I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1);
+        POSTING_READ(BLC_PWM_PCH_CTL1);
+        I915_WRITE(BLC_PWM_PCH_CTL1, pch_ctl1 | BLM_PCH_PWM_ENABLE);
 }
 
 static void i9xx_enable_backlight(struct intel_connector *connector)
 {
+        struct drm_device *dev = connector->base.dev;
+        struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_panel *panel = &connector->panel;
+        u32 ctl, freq;
+
+        ctl = I915_READ(BLC_PWM_CTL);
+        if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
+                WARN(1, "backlight already enabled\n");
+                I915_WRITE(BLC_PWM_CTL, 0);
+        }
 
+        freq = panel->backlight.max;
+        if (panel->backlight.combination_mode)
+                freq /= 0xff;
+
+        ctl = freq << 17;
+        if (IS_GEN2(dev) && panel->backlight.combination_mode)
+                ctl |= BLM_LEGACY_MODE;
+        if (IS_PINEVIEW(dev) && panel->backlight.active_low_pwm)
+                ctl |= BLM_POLARITY_PNV;
+
+        I915_WRITE(BLC_PWM_CTL, ctl);
+        POSTING_READ(BLC_PWM_CTL);
+
+        /* XXX: combine this into above write? */
         intel_panel_actually_set_backlight(connector, panel->backlight.level);
 }
 
@@ -772,25 +797,33 @@ static void i965_enable_backlight(struct intel_connector *connector)
         struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_panel *panel = &connector->panel;
         enum pipe pipe = intel_get_pipe_from_connector(connector);
-        u32 tmp;
+        u32 ctl, ctl2, freq;
 
-        tmp = I915_READ(BLC_PWM_CTL2);
+        ctl2 = I915_READ(BLC_PWM_CTL2);
+        if (ctl2 & BLM_PWM_ENABLE) {
+                WARN(1, "backlight already enabled\n");
+                ctl2 &= ~BLM_PWM_ENABLE;
+                I915_WRITE(BLC_PWM_CTL2, ctl2);
+        }
 
-        /* Note that this can also get called through dpms changes. And
-         * we don't track the backlight dpms state, hence check whether
-         * we have to do anything first. */
-        if (tmp & BLM_PWM_ENABLE)
-                return;
+        freq = panel->backlight.max;
+        if (panel->backlight.combination_mode)
+                freq /= 0xff;
 
-        tmp &= ~BLM_PIPE_SELECT;
-        tmp |= BLM_PIPE(pipe);
-        tmp &= ~BLM_PWM_ENABLE;
-
-        I915_WRITE(BLC_PWM_CTL2, tmp);
-        POSTING_READ(BLC_PWM_CTL2);
-        I915_WRITE(BLC_PWM_CTL2, tmp | BLM_PWM_ENABLE);
+        ctl = freq << 16;
+        I915_WRITE(BLC_PWM_CTL, ctl);
 
+        /* XXX: combine this into above write? */
         intel_panel_actually_set_backlight(connector, panel->backlight.level);
+
+        ctl2 = BLM_PIPE(pipe);
+        if (panel->backlight.combination_mode)
+                ctl2 |= BLM_COMBINATION_MODE;
+        if (panel->backlight.active_low_pwm)
+                ctl2 |= BLM_POLARITY_I965;
+        I915_WRITE(BLC_PWM_CTL2, ctl2);
+        POSTING_READ(BLC_PWM_CTL2);
+        I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
 }
 
 static void vlv_enable_backlight(struct intel_connector *connector)
@@ -799,23 +832,27 @@ static void vlv_enable_backlight(struct intel_connector *connector)
         struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_panel *panel = &connector->panel;
         enum pipe pipe = intel_get_pipe_from_connector(connector);
-        u32 tmp;
+        u32 ctl, ctl2;
 
-        tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe));
+        ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
+        if (ctl2 & BLM_PWM_ENABLE) {
+                WARN(1, "backlight already enabled\n");
+                ctl2 &= ~BLM_PWM_ENABLE;
+                I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
+        }
 
-        /* Note that this can also get called through dpms changes. And
-         * we don't track the backlight dpms state, hence check whether
-         * we have to do anything first. */
-        if (tmp & BLM_PWM_ENABLE)
-                return;
+        ctl = panel->backlight.max << 16;
+        I915_WRITE(VLV_BLC_PWM_CTL(pipe), ctl);
 
-        tmp &= ~BLM_PWM_ENABLE;
+        /* XXX: combine this into above write? */
+        intel_panel_actually_set_backlight(connector, panel->backlight.level);
 
-        I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp);
+        ctl2 = 0;
+        if (panel->backlight.active_low_pwm)
+                ctl2 |= BLM_POLARITY_I965;
+        I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2);
         POSTING_READ(VLV_BLC_PWM_CTL2(pipe));
-        I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp | BLM_PWM_ENABLE);
-
-        intel_panel_actually_set_backlight(connector, panel->backlight.level);
+        I915_WRITE(VLV_BLC_PWM_CTL2(pipe), ctl2 | BLM_PWM_ENABLE);
 }
 
 void intel_panel_enable_backlight(struct intel_connector *connector)