[v7,4/7] drm/i915/tgl: Do modeset to enable and configure DC3CO exitline.

Submitted by Anshuamn Gupta on Sept. 7, 2019, 5:14 p.m.

Details

Message ID 20190907171443.16181-5-anshuman.gupta@intel.com
State New
Headers show
Series "DC3CO Support for TGL" ( rev: 8 7 ) in Intel GFX

Browsing this patch as part of:
"DC3CO Support for TGL" rev 7 in Intel GFX
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Commit Message

Anshuamn Gupta Sept. 7, 2019, 5:14 p.m.
DC3CO enabling B.Specs sequence requires to enable end configure
exit scanlines to TRANS_EXITLINE register, programming this register
has to be part of modeset sequence as this can't be change when
transcoder or port is enabled.
When system boots with only eDP panel there may not be real
modeset as BIOS has already programmed the necessary registers,
therefore it needs to force a modeset at bootup to enable and configure
DC3CO exitline.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c  |   5 +
 .../drm/i915/display/intel_display_power.c    | 108 ++++++++++++++++++
 .../drm/i915/display/intel_display_power.h    |   7 ++
 .../drm/i915/display/intel_display_types.h    |   1 +
 drivers/gpu/drm/i915/i915_drv.h               |   2 +
 drivers/gpu/drm/i915/intel_pm.c               |   2 +-
 drivers/gpu/drm/i915/intel_pm.h               |   2 +
 7 files changed, 126 insertions(+), 1 deletion(-)

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diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 3b5275ab66cf..84488f87d058 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -7409,6 +7409,8 @@  static int intel_crtc_compute_config(struct intel_crtc *crtc,
 	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 	int clock_limit = dev_priv->max_dotclk_freq;
 
+	tgl_dc3co_crtc_compute_config(dev_priv, pipe_config);
+
 	if (INTEL_GEN(dev_priv) < 4) {
 		clock_limit = dev_priv->max_cdclk_freq * 9 / 10;
 
@@ -10474,6 +10476,8 @@  static bool haswell_get_pipe_config(struct intel_crtc *crtc,
 		pipe_config->pixel_multiplier = 1;
 	}
 
+	tgl_dc3co_crtc_get_config(pipe_config);
+
 out:
 	for_each_power_domain(power_domain, power_domain_mask)
 		intel_display_power_put(dev_priv,
@@ -12739,6 +12743,7 @@  intel_pipe_config_compare(const struct intel_crtc_state *current_config,
 
 	PIPE_CONF_CHECK_I(pixel_multiplier);
 	PIPE_CONF_CHECK_I(output_format);
+	PIPE_CONF_CHECK_BOOL(has_dc3co_exitline);
 	PIPE_CONF_CHECK_BOOL(has_hdmi_sink);
 	if ((INTEL_GEN(dev_priv) < 8 && !IS_HASWELL(dev_priv)) ||
 	    IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index 83b10f61ee42..ecce118b5b0e 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -19,6 +19,7 @@ 
 #include "intel_hotplug.h"
 #include "intel_sideband.h"
 #include "intel_tc.h"
+#include "intel_pm.h"
 
 bool intel_display_power_well_is_enabled(struct drm_i915_private *dev_priv,
 					 enum i915_power_well_id power_well_id);
@@ -772,6 +773,113 @@  static void gen9_set_dc_state(struct drm_i915_private *dev_priv, u32 state)
 	dev_priv->csr.dc_state = val & mask;
 }
 
+void tgl_disable_psr2_transcoder_exitline(const struct intel_crtc_state *cstate)
+{
+	struct drm_i915_private *dev_priv = to_i915(cstate->base.crtc->dev);
+	u32 val;
+
+	if (!IS_TIGERLAKE(dev_priv))
+		return;
+
+	val = I915_READ(EXITLINE(cstate->cpu_transcoder));
+	val &= ~EXITLINE_ENABLE;
+	I915_WRITE(EXITLINE(cstate->cpu_transcoder), val);
+}
+
+void tgl_enable_psr2_transcoder_exitline(const struct intel_crtc_state *cstate)
+{
+	u32 linetime_us, val, exit_scanlines;
+	u32 crtc_vdisplay = cstate->base.adjusted_mode.crtc_vdisplay;
+	struct drm_i915_private *dev_priv = to_i915(cstate->base.crtc->dev);
+
+	if (!IS_TIGERLAKE(dev_priv))
+		return;
+
+	linetime_us = fixed16_to_u32_round_up(intel_get_linetime_us(cstate));
+	if (WARN_ON(!linetime_us))
+		return;
+	/*
+	 * DC3CO Exit time 200us B.Spec 49196
+	 * PSR2 transcoder Early Exit scanlines = ROUNDUP(200 / line time) + 1
+	 * Exit line event need to program above calculated scan lines before
+	 * next VBLANK.
+	 */
+	exit_scanlines = DIV_ROUND_UP(200, linetime_us) + 1;
+	if (WARN_ON(exit_scanlines > crtc_vdisplay))
+		return;
+
+	exit_scanlines = crtc_vdisplay - exit_scanlines;
+	exit_scanlines <<= EXITLINE_SHIFT;
+	val = I915_READ(EXITLINE(cstate->cpu_transcoder));
+	val &= ~(EXITLINE_MASK | EXITLINE_ENABLE);
+	val |= exit_scanlines;
+	val |= EXITLINE_ENABLE;
+	I915_WRITE(EXITLINE(cstate->cpu_transcoder), val);
+}
+
+static bool tgl_dc3co_is_edp_connected(struct intel_crtc_state  *crtc_state)
+{
+	struct drm_atomic_state *state = crtc_state->base.state;
+	struct drm_connector *connector;
+	struct drm_connector_state *connector_state;
+	int i;
+
+	for_each_new_connector_in_state(state, connector, connector_state, i) {
+		if (connector->status == connector_status_connected &&
+		    connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
+/*
+ * DC3CO requires to enable exitline and program DC3CO requires
+ * exit scanlines to TRANS_EXITLINE register, which should only
+ * change before transcoder or port are enabled.
+ * This requires to disable the fastset at boot for eDP output.
+ */
+void tgl_dc3co_crtc_compute_config(struct drm_i915_private *dev_priv,
+				   struct intel_crtc_state *crtc_state)
+{
+	if (!IS_TIGERLAKE(dev_priv))
+		return;
+
+	if (!(dev_priv->csr.allowed_dc_mask & DC_STATE_EN_DC3CO))
+		return;
+
+	dev_priv->csr.dc3co_crtc = NULL;
+
+	if (crtc_state->has_psr2 && crtc_state->base.active) {
+		if (tgl_dc3co_is_edp_connected(crtc_state)) {
+			crtc_state->has_dc3co_exitline = true;
+			dev_priv->csr.dc3co_crtc =
+			to_intel_crtc(crtc_state->base.crtc);
+		}
+	}
+}
+
+void tgl_dc3co_crtc_get_config(struct intel_crtc_state *crtc_state)
+{
+	u32 val;
+	struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev);
+
+	if (!IS_TIGERLAKE(dev_priv))
+		return;
+
+	if (!(dev_priv->csr.allowed_dc_mask & DC_STATE_EN_DC3CO))
+		return;
+
+	if (crtc_state->cpu_transcoder == TRANSCODER_A) {
+		val = I915_READ(EXITLINE(crtc_state->cpu_transcoder));
+		if (val & EXITLINE_ENABLE)
+			crtc_state->has_dc3co_exitline = true;
+		else
+			crtc_state->has_dc3co_exitline = false;
+	}
+}
+
 static void tgl_allow_dc3co(struct drm_i915_private *dev_priv)
 {
 	if (!dev_priv->psr.sink_psr2_support)
diff --git a/drivers/gpu/drm/i915/display/intel_display_power.h b/drivers/gpu/drm/i915/display/intel_display_power.h
index 69ebde992342..d77a5a53f543 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.h
+++ b/drivers/gpu/drm/i915/display/intel_display_power.h
@@ -12,6 +12,8 @@ 
 
 struct drm_i915_private;
 struct intel_encoder;
+struct intel_crtc_state;
+struct intel_atomic_state;
 
 enum intel_display_power_domain {
 	POWER_DOMAIN_DISPLAY_CORE,
@@ -259,6 +261,11 @@  void intel_display_power_suspend(struct drm_i915_private *i915);
 void intel_display_power_resume(struct drm_i915_private *i915);
 void tgl_set_target_dc_state(struct drm_i915_private *dev_priv, u32 state,
 			     bool psr2_deep_sleep);
+void tgl_dc3co_crtc_compute_config(struct drm_i915_private *dev_priv,
+				   struct intel_crtc_state *crtc_state);
+void tgl_dc3co_crtc_get_config(struct intel_crtc_state *crtc_state);
+void tgl_disable_psr2_transcoder_exitline(const struct intel_crtc_state *state);
+void tgl_enable_psr2_transcoder_exitline(const struct intel_crtc_state *state);
 
 const char *
 intel_display_power_domain_str(enum intel_display_power_domain domain);
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index d5cc4b810d9e..22f8fe0a34d0 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -871,6 +871,7 @@  struct intel_crtc_state {
 
 	bool has_psr;
 	bool has_psr2;
+	bool has_dc3co_exitline;
 
 	/*
 	 * Frequence the dpll for the port should run at. Differs from the
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 999da5d2da0b..3218b0319852 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -339,6 +339,8 @@  struct intel_csr {
 	u32 max_dc_state;
 	u32 allowed_dc_mask;
 	intel_wakeref_t wakeref;
+	/* cache the crtc on which DC3CO will be allowed */
+	struct intel_crtc *dc3co_crtc;
 };
 
 enum i915_cache_level {
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 528e90ed5de4..7352c0cb88d0 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4588,7 +4588,7 @@  skl_wm_method2(u32 pixel_rate, u32 pipe_htotal, u32 latency,
 	return ret;
 }
 
-static uint_fixed_16_16_t
+uint_fixed_16_16_t
 intel_get_linetime_us(const struct intel_crtc_state *crtc_state)
 {
 	u32 pixel_rate;
diff --git a/drivers/gpu/drm/i915/intel_pm.h b/drivers/gpu/drm/i915/intel_pm.h
index e3573e1e16e3..454e92c06dff 100644
--- a/drivers/gpu/drm/i915/intel_pm.h
+++ b/drivers/gpu/drm/i915/intel_pm.h
@@ -8,6 +8,7 @@ 
 
 #include <linux/types.h>
 
+#include "i915_drv.h"
 #include "i915_reg.h"
 
 struct drm_device;
@@ -76,6 +77,7 @@  u64 intel_rc6_residency_ns(struct drm_i915_private *dev_priv, i915_reg_t reg);
 u64 intel_rc6_residency_us(struct drm_i915_private *dev_priv, i915_reg_t reg);
 
 u32 intel_get_cagf(struct drm_i915_private *dev_priv, u32 rpstat1);
+uint_fixed_16_16_t intel_get_linetime_us(const struct intel_crtc_state *cstate);
 
 unsigned long i915_chipset_val(struct drm_i915_private *dev_priv);
 unsigned long i915_mch_val(struct drm_i915_private *dev_priv);

Comments

On Sat, Sep 07, 2019 at 10:44:40PM +0530, Anshuman Gupta wrote:
> DC3CO enabling B.Specs sequence requires to enable end configure
> exit scanlines to TRANS_EXITLINE register, programming this register
> has to be part of modeset sequence as this can't be change when
> transcoder or port is enabled.
> When system boots with only eDP panel there may not be real
> modeset as BIOS has already programmed the necessary registers,
> therefore it needs to force a modeset at bootup to enable and configure
> DC3CO exitline.
> 
> Cc: Jani Nikula <jani.nikula@intel.com>
> Cc: Imre Deak <imre.deak@intel.com>
> Cc: Animesh Manna <animesh.manna@intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c  |   5 +
>  .../drm/i915/display/intel_display_power.c    | 108 ++++++++++++++++++
>  .../drm/i915/display/intel_display_power.h    |   7 ++
>  .../drm/i915/display/intel_display_types.h    |   1 +
>  drivers/gpu/drm/i915/i915_drv.h               |   2 +
>  drivers/gpu/drm/i915/intel_pm.c               |   2 +-
>  drivers/gpu/drm/i915/intel_pm.h               |   2 +
>  7 files changed, 126 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 3b5275ab66cf..84488f87d058 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -7409,6 +7409,8 @@ static int intel_crtc_compute_config(struct intel_crtc *crtc,
>  	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
>  	int clock_limit = dev_priv->max_dotclk_freq;
>  
> +	tgl_dc3co_crtc_compute_config(dev_priv, pipe_config);
> +

This is an encoder specific state so should be done from the encoder
compute config hook.

>  	if (INTEL_GEN(dev_priv) < 4) {
>  		clock_limit = dev_priv->max_cdclk_freq * 9 / 10;
>  
> @@ -10474,6 +10476,8 @@ static bool haswell_get_pipe_config(struct intel_crtc *crtc,
>  		pipe_config->pixel_multiplier = 1;
>  	}
>  
> +	tgl_dc3co_crtc_get_config(pipe_config);
> +
>  out:
>  	for_each_power_domain(power_domain, power_domain_mask)
>  		intel_display_power_put(dev_priv,
> @@ -12739,6 +12743,7 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
>  
>  	PIPE_CONF_CHECK_I(pixel_multiplier);
>  	PIPE_CONF_CHECK_I(output_format);
> +	PIPE_CONF_CHECK_BOOL(has_dc3co_exitline);
>  	PIPE_CONF_CHECK_BOOL(has_hdmi_sink);
>  	if ((INTEL_GEN(dev_priv) < 8 && !IS_HASWELL(dev_priv)) ||
>  	    IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
> index 83b10f61ee42..ecce118b5b0e 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_power.c
> @@ -19,6 +19,7 @@
>  #include "intel_hotplug.h"
>  #include "intel_sideband.h"
>  #include "intel_tc.h"
> +#include "intel_pm.h"
>  
>  bool intel_display_power_well_is_enabled(struct drm_i915_private *dev_priv,
>  					 enum i915_power_well_id power_well_id);
> @@ -772,6 +773,113 @@ static void gen9_set_dc_state(struct drm_i915_private *dev_priv, u32 state)
>  	dev_priv->csr.dc_state = val & mask;
>  }
>  
> +void tgl_disable_psr2_transcoder_exitline(const struct intel_crtc_state *cstate)

Please add these in the patch that uses them, to make review easier.

> +{
> +	struct drm_i915_private *dev_priv = to_i915(cstate->base.crtc->dev);
> +	u32 val;
> +
> +	if (!IS_TIGERLAKE(dev_priv))
> +		return;
> +
> +	val = I915_READ(EXITLINE(cstate->cpu_transcoder));
> +	val &= ~EXITLINE_ENABLE;
> +	I915_WRITE(EXITLINE(cstate->cpu_transcoder), val);
> +}
> +
> +void tgl_enable_psr2_transcoder_exitline(const struct intel_crtc_state *cstate)
> +{
> +	u32 linetime_us, val, exit_scanlines;
> +	u32 crtc_vdisplay = cstate->base.adjusted_mode.crtc_vdisplay;
> +	struct drm_i915_private *dev_priv = to_i915(cstate->base.crtc->dev);
> +
> +	if (!IS_TIGERLAKE(dev_priv))
> +		return;
> +
> +	linetime_us = fixed16_to_u32_round_up(intel_get_linetime_us(cstate));
> +	if (WARN_ON(!linetime_us))
> +		return;
> +	/*
> +	 * DC3CO Exit time 200us B.Spec 49196
> +	 * PSR2 transcoder Early Exit scanlines = ROUNDUP(200 / line time) + 1
> +	 * Exit line event need to program above calculated scan lines before
> +	 * next VBLANK.
> +	 */
> +	exit_scanlines = DIV_ROUND_UP(200, linetime_us) + 1;

exit_scanlines could be the state that you calculate during the PSR compute
config phase, only programming that calculated state here.

> +	if (WARN_ON(exit_scanlines > crtc_vdisplay))
> +		return;
> +
> +	exit_scanlines = crtc_vdisplay - exit_scanlines;
> +	exit_scanlines <<= EXITLINE_SHIFT;
> +	val = I915_READ(EXITLINE(cstate->cpu_transcoder));
> +	val &= ~(EXITLINE_MASK | EXITLINE_ENABLE);
> +	val |= exit_scanlines;
> +	val |= EXITLINE_ENABLE;
> +	I915_WRITE(EXITLINE(cstate->cpu_transcoder), val);
> +}
> +
> +static bool tgl_dc3co_is_edp_connected(struct intel_crtc_state  *crtc_state)
> +{
> +	struct drm_atomic_state *state = crtc_state->base.state;
> +	struct drm_connector *connector;
> +	struct drm_connector_state *connector_state;
> +	int i;
> +
> +	for_each_new_connector_in_state(state, connector, connector_state, i) {
> +		if (connector->status == connector_status_connected &&
> +		    connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
> +			return true;
> +		}
> +	}
> +
> +	return false;
> +}
> +
> +/*
> + * DC3CO requires to enable exitline and program DC3CO requires
> + * exit scanlines to TRANS_EXITLINE register, which should only
> + * change before transcoder or port are enabled.
> + * This requires to disable the fastset at boot for eDP output.
> + */
> +void tgl_dc3co_crtc_compute_config(struct drm_i915_private *dev_priv,
> +				   struct intel_crtc_state *crtc_state)
> +{
> +	if (!IS_TIGERLAKE(dev_priv))
> +		return;
> +
> +	if (!(dev_priv->csr.allowed_dc_mask & DC_STATE_EN_DC3CO))
> +		return;
> +
> +	dev_priv->csr.dc3co_crtc = NULL;

This will correspond to psr.pipe, so I can't see why we need to
calcualte it separately.

> +
> +	if (crtc_state->has_psr2 && crtc_state->base.active) {
> +		if (tgl_dc3co_is_edp_connected(crtc_state)) {
> +			crtc_state->has_dc3co_exitline = true;

I think we should rather calculate the exit_scanline value itself (as
you calculate that now in tgl_enable_psr2_transcoder_exitline()). By
doing that in the encoder compute config hook, we'll also know that we
have eDP connected, so wouldn't have to check for that either.

> +			dev_priv->csr.dc3co_crtc =
> +			to_intel_crtc(crtc_state->base.crtc);
> +		}
> +	}
> +}
> +
> +void tgl_dc3co_crtc_get_config(struct intel_crtc_state *crtc_state)
> +{
> +	u32 val;
> +	struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev);
> +
> +	if (!IS_TIGERLAKE(dev_priv))
> +		return;
> +
> +	if (!(dev_priv->csr.allowed_dc_mask & DC_STATE_EN_DC3CO))
> +		return;
> +
> +	if (crtc_state->cpu_transcoder == TRANSCODER_A) {
> +		val = I915_READ(EXITLINE(crtc_state->cpu_transcoder));
> +		if (val & EXITLINE_ENABLE)
> +			crtc_state->has_dc3co_exitline = true;
> +		else
> +			crtc_state->has_dc3co_exitline = false;

Based on the above we should read out the exit_scanline value itself (in
the encoder's get_config hook).

> +	}
> +}
> +
>  static void tgl_allow_dc3co(struct drm_i915_private *dev_priv)
>  {
>  	if (!dev_priv->psr.sink_psr2_support)
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power.h b/drivers/gpu/drm/i915/display/intel_display_power.h
> index 69ebde992342..d77a5a53f543 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_power.h
> @@ -12,6 +12,8 @@
>  
>  struct drm_i915_private;
>  struct intel_encoder;
> +struct intel_crtc_state;
> +struct intel_atomic_state;
>  
>  enum intel_display_power_domain {
>  	POWER_DOMAIN_DISPLAY_CORE,
> @@ -259,6 +261,11 @@ void intel_display_power_suspend(struct drm_i915_private *i915);
>  void intel_display_power_resume(struct drm_i915_private *i915);
>  void tgl_set_target_dc_state(struct drm_i915_private *dev_priv, u32 state,
>  			     bool psr2_deep_sleep);
> +void tgl_dc3co_crtc_compute_config(struct drm_i915_private *dev_priv,
> +				   struct intel_crtc_state *crtc_state);
> +void tgl_dc3co_crtc_get_config(struct intel_crtc_state *crtc_state);
> +void tgl_disable_psr2_transcoder_exitline(const struct intel_crtc_state *state);
> +void tgl_enable_psr2_transcoder_exitline(const struct intel_crtc_state *state);
>  
>  const char *
>  intel_display_power_domain_str(enum intel_display_power_domain domain);
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index d5cc4b810d9e..22f8fe0a34d0 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -871,6 +871,7 @@ struct intel_crtc_state {
>  
>  	bool has_psr;
>  	bool has_psr2;
> +	bool has_dc3co_exitline;
>  
>  	/*
>  	 * Frequence the dpll for the port should run at. Differs from the
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 999da5d2da0b..3218b0319852 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -339,6 +339,8 @@ struct intel_csr {
>  	u32 max_dc_state;
>  	u32 allowed_dc_mask;
>  	intel_wakeref_t wakeref;
> +	/* cache the crtc on which DC3CO will be allowed */
> +	struct intel_crtc *dc3co_crtc;
>  };
>  
>  enum i915_cache_level {
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 528e90ed5de4..7352c0cb88d0 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -4588,7 +4588,7 @@ skl_wm_method2(u32 pixel_rate, u32 pipe_htotal, u32 latency,
>  	return ret;
>  }
>  
> -static uint_fixed_16_16_t
> +uint_fixed_16_16_t
>  intel_get_linetime_us(const struct intel_crtc_state *crtc_state)
>  {
>  	u32 pixel_rate;
> diff --git a/drivers/gpu/drm/i915/intel_pm.h b/drivers/gpu/drm/i915/intel_pm.h
> index e3573e1e16e3..454e92c06dff 100644
> --- a/drivers/gpu/drm/i915/intel_pm.h
> +++ b/drivers/gpu/drm/i915/intel_pm.h
> @@ -8,6 +8,7 @@
>  
>  #include <linux/types.h>
>  
> +#include "i915_drv.h"
>  #include "i915_reg.h"
>  
>  struct drm_device;
> @@ -76,6 +77,7 @@ u64 intel_rc6_residency_ns(struct drm_i915_private *dev_priv, i915_reg_t reg);
>  u64 intel_rc6_residency_us(struct drm_i915_private *dev_priv, i915_reg_t reg);
>  
>  u32 intel_get_cagf(struct drm_i915_private *dev_priv, u32 rpstat1);
> +uint_fixed_16_16_t intel_get_linetime_us(const struct intel_crtc_state *cstate);
>  
>  unsigned long i915_chipset_val(struct drm_i915_private *dev_priv);
>  unsigned long i915_mch_val(struct drm_i915_private *dev_priv);
> -- 
> 2.21.0
>