From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Powergate the PHY lanes when they're not needed. For HDMI all four lanes
are needed always, but for DP we can enable only the needed lanes. And
when the port is not used all lanes can be power gated. This could
reduce power consumption a bit when only a subset of the lanes in the
PHY are required.
A bit of extra care is needed to reconstruct the initial state of the
DPIO_PHY_CONTROL register since we can't read it. So instead we read the
actual lane status from the DPLL/PHY_STATUS registers and use that to
determine which lanes ought to be powergated initially.
Also sprinkle a few debug prints around so that we can monitor the
DPIO_PHY_STATUS changes without having to read it and risk corrupting
it.
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/i915_reg.h | 2 +
drivers/gpu/drm/i915/intel_dp.c | 8 ++++
drivers/gpu/drm/i915/intel_drv.h | 2 +
drivers/gpu/drm/i915/intel_hdmi.c | 5 +++
drivers/gpu/drm/i915/intel_runtime_pm.c | 69 +++++++++++++++++++++++++++++++--
5 files changed, 82 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 977bad6..34c366a 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1887,10 +1887,12 @@ enum skl_disp_power_wells {
#define DPIO_PHY_STATUS (VLV_DISPLAY_BASE + 0x6240)
#define DPLL_PORTD_READY_MASK (0xf)
#define DISPLAY_PHY_CONTROL (VLV_DISPLAY_BASE + 0x60100)
+#define PHY_CH_POWER_DOWN_OVRD_EN(phy, ch) (1 << (2*(phy)+(ch)+27))
#define PHY_LDO_DELAY_0NS 0x0
#define PHY_LDO_DELAY_200NS 0x1
#define PHY_LDO_DELAY_600NS 0x2
#define PHY_LDO_SEQ_DELAY(delay, phy) ((delay) << (2*(phy)+23))
+#define PHY_CH_POWER_DOWN_OVRD(mask, phy, ch) ((mask) << (8*(phy)+4*(ch)+11))
#define PHY_CH_SU_PSR 0x1
#define PHY_CH_DEEP_PSR 0x7
#define PHY_CH_POWER_MODE(mode, phy, ch) ((mode) << (6*(phy)+3*(ch)+2))
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index ac38fd8..0b43f99 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2336,6 +2336,8 @@ static void chv_post_disable_dp(struct intel_encoder *encoder)
intel_dp_link_down(intel_dp);
+ chv_powergate_phy_lanes(encoder, 0xf);
+
mutex_lock(&dev_priv->dpio_lock);
/* Propagate soft reset to data lane reset */
@@ -2482,6 +2484,12 @@ static void intel_enable_dp(struct intel_encoder *encoder)
if (IS_VALLEYVIEW(dev))
vlv_init_panel_power_sequencer(intel_dp);
+ if (IS_CHERRYVIEW(dev)) {
+ /* FIXME deal with lane reversal */
+ lane_mask = 0xf & ~((1 << intel_dp->lane_count) - 1);
+ chv_powergate_phy_lanes(encoder, lane_mask);
+ }
+
intel_dp_enable_port(intel_dp);
edp_panel_vdd_on(intel_dp);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 3ec829a..54bcca8 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1238,6 +1238,8 @@ void intel_runtime_pm_put(struct drm_i915_private *dev_priv);
void intel_display_set_init_power(struct drm_i915_private *dev, bool enable);
+void chv_powergate_phy_lanes(struct intel_encoder *encoder, unsigned int mask);
+
/* intel_pm.c */
void intel_init_clock_gating(struct drm_device *dev);
void intel_suspend_hw(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 24b0aa1..f5842c3 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -916,6 +916,9 @@ static void intel_disable_hdmi(struct intel_encoder *encoder)
I915_WRITE(intel_hdmi->hdmi_reg, temp);
POSTING_READ(intel_hdmi->hdmi_reg);
}
+
+ if (IS_CHERRYVIEW(dev))
+ chv_powergate_phy_lanes(encoder, 0xf);
}
static int hdmi_portclock_limit(struct intel_hdmi *hdmi, bool respect_dvi_limit)
@@ -1634,6 +1637,8 @@ static void chv_hdmi_pre_enable(struct intel_encoder *encoder)
intel_crtc->config->has_hdmi_sink,
adjusted_mode);
+ chv_powergate_phy_lanes(encoder, 0x0);
+
intel_enable_hdmi(encoder);
vlv_wait_port_ready(dev_priv, dport, 0x0);
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 5cd8a51..d9e00d3 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -668,6 +668,9 @@ static void chv_dpio_cmn_power_well_enable(struct drm_i915_private *dev_priv,
dev_priv->chv_phy_control |= PHY_COM_LANE_RESET_DEASSERT(phy);
I915_WRITE(DISPLAY_PHY_CONTROL, dev_priv->chv_phy_control);
+
+ DRM_DEBUG_KMS("Enabled DPIO PHY%d (DPIO_PHY_CONTROL=0x%08x)\n",
+ phy, dev_priv->chv_phy_control);
}
static void chv_dpio_cmn_power_well_disable(struct drm_i915_private *dev_priv,
@@ -680,10 +683,15 @@ static void chv_dpio_cmn_power_well_disable(struct drm_i915_private *dev_priv,
if (power_well->data == PUNIT_POWER_WELL_DPIO_CMN_BC) {
phy = DPIO_PHY0;
+ dev_priv->chv_phy_control |=
+ PHY_CH_POWER_DOWN_OVRD(0xf, phy, DPIO_CH0) |
+ PHY_CH_POWER_DOWN_OVRD(0xf, phy, DPIO_CH1);
assert_pll_disabled(dev_priv, PIPE_A);
assert_pll_disabled(dev_priv, PIPE_B);
} else {
phy = DPIO_PHY1;
+ dev_priv->chv_phy_control |=
+ PHY_CH_POWER_DOWN_OVRD(0xf, phy, DPIO_CH0);
assert_pll_disabled(dev_priv, PIPE_C);
}
@@ -691,6 +699,25 @@ static void chv_dpio_cmn_power_well_disable(struct drm_i915_private *dev_priv,
I915_WRITE(DISPLAY_PHY_CONTROL, dev_priv->chv_phy_control);
vlv_set_power_well(dev_priv, power_well, false);
+
+ DRM_DEBUG_KMS("Disabled DPIO PHY%d (DPIO_PHY_CONTROL=0x%08x)\n",
+ phy, dev_priv->chv_phy_control);
+}
+
+void chv_powergate_phy_lanes(struct intel_encoder *encoder, unsigned int mask)
+{
+ struct drm_device *dev = encoder->base.dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+ enum dpio_phy phy = DPIO_PHY(intel_crtc->pipe);
+ enum dpio_channel ch = vlv_dport_to_channel(enc_to_dig_port(&encoder->base));
+
+ dev_priv->chv_phy_control &= ~PHY_CH_POWER_DOWN_OVRD(0xf, phy, ch);
+ dev_priv->chv_phy_control |= PHY_CH_POWER_DOWN_OVRD(mask, phy, ch);
+ I915_WRITE(DISPLAY_PHY_CONTROL, dev_priv->chv_phy_control);
+
+ DRM_DEBUG_KMS("Power gating DPIO PHY%d CH%d lanes 0x%x (DPIO_PHY_CONTROL=0x%08x)\n",
+ phy, ch, mask, dev_priv->chv_phy_control);
}
