drm/i915: Initial implementation of PSR2 selective fetch

All GEN12 platforms supports PSR2 selective fetch but not all GEN12
platforms supports PSR2 hardware tracking(aka RKL).

This feature consists in software programming registers with the
damaged area of each plane this way hardware will only fetch from
memory those areas and sent the PSR2 selective update blocks to panel,
saving even more power.

But as initial step it is only enabling the full frame fetch at
every flip, the actual selective fetch part will come in a future
patch.

Also this is only handling the page flip side, it is still completely
missing frontbuffer modifications, that is why the
enable_psr2_sel_fetch parameter was added.

v3:
- calling intel_psr2_sel_fetch_update() during the atomic check phase
(Ville)

BSpec: 55229
Cc: Ville Syrjälä <[e-mail]>
Cc: Imre Deak <[e-mail]>
Cc: Gwan-gyeong Mun <[e-mail]>
Cc: Rodrigo Vivi <[e-mail]>
Cc: Dhinakaran Pandiyan <[e-mail]>
Reviewed-by: Gwan-gyeong Mun <[e-mail]>
Signed-off-by: José Roberto de Souza <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]
Signed-off-by: Rodrigo Vivi <[e-mail]>

drivers/gpu/drm/i915/display/intel_display.c

···
 
 	}
 
+	if (!mode_changed)
+		intel_psr2_sel_fetch_update(state, crtc);
+
 	return 0;
 }
 
···
 
 		if (new_crtc_state->update_pipe)
 			intel_pipe_fastset(old_crtc_state, new_crtc_state);
+
+		intel_psr2_program_trans_man_trk_ctl(new_crtc_state);
 	}
 
 	if (dev_priv->display.atomic_update_watermarks)

drivers/gpu/drm/i915/display/intel_display_debugfs.c

···
 			su_blocks = su_blocks >> PSR2_SU_STATUS_SHIFT(frame);
 			seq_printf(m, "%d\t%d\n", frame, su_blocks);
 		}
+
+		seq_printf(m, "PSR2 selective fetch: %s\n",
+			   enableddisabled(psr->psr2_sel_fetch_enabled));
 	}
 
 unlock:

drivers/gpu/drm/i915/display/intel_display_types.h

···
 
 	bool has_psr;
 	bool has_psr2;
+	bool enable_psr2_sel_fetch;
 	u32 dc3co_exitline;
 
 	/*
···
 
 	/* For DSB related info */
 	struct intel_dsb *dsb;
+
+	u32 psr2_man_track_ctl;
 };
 
 enum intel_pipe_crc_source {

drivers/gpu/drm/i915/display/intel_psr.c

···
 		val |= EDP_PSR2_FAST_WAKE(7);
 	}
 
+	if (dev_priv->psr.psr2_sel_fetch_enabled)
+		intel_de_write(dev_priv,
+			       PSR2_MAN_TRK_CTL(dev_priv->psr.transcoder),
+			       PSR2_MAN_TRK_CTL_ENABLE);
+	else if (HAS_PSR2_SEL_FETCH(dev_priv))
+		intel_de_write(dev_priv,
+			       PSR2_MAN_TRK_CTL(dev_priv->psr.transcoder), 0);
+
 	/*
 	 * PSR2 HW is incorrectly using EDP_PSR_TP1_TP3_SEL and BSpec is
 	 * recommending keep this bit unset while PSR2 is enabled.
···
 	crtc_state->dc3co_exitline = crtc_vdisplay - exit_scanlines;
 }
 
+static bool intel_psr2_sel_fetch_config_valid(struct intel_dp *intel_dp,
+					      struct intel_crtc_state *crtc_state)
+{
+	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
+	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
+	struct intel_plane_state *plane_state;
+	struct intel_plane *plane;
+	int i;
+
+	if (!dev_priv->params.enable_psr2_sel_fetch) {
+		drm_dbg_kms(&dev_priv->drm,
+			    "PSR2 sel fetch not enabled, disabled by parameter\n");
+		return false;
+	}
+
+	if (crtc_state->uapi.async_flip) {
+		drm_dbg_kms(&dev_priv->drm,
+			    "PSR2 sel fetch not enabled, async flip enabled\n");
+		return false;
+	}
+
+	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
+		if (plane_state->uapi.rotation != DRM_MODE_ROTATE_0) {
+			drm_dbg_kms(&dev_priv->drm,
+				    "PSR2 sel fetch not enabled, plane rotated\n");
+			return false;
+		}
+	}
+
+	return crtc_state->enable_psr2_sel_fetch = true;
+}
+
 static bool intel_psr2_config_valid(struct intel_dp *intel_dp,
 				    struct intel_crtc_state *crtc_state)
 {
···
 		return false;
 	}
 
-	/*
-	 * Some platforms lack PSR2 HW tracking and instead require manual
-	 * tracking by software.  In this case, the driver is required to track
-	 * the areas that need updates and program hardware to send selective
-	 * updates.
-	 *
-	 * So until the software tracking is implemented, PSR2 needs to be
-	 * disabled for platforms without PSR2 HW tracking.
-	 */
-	if (!HAS_PSR_HW_TRACKING(dev_priv)) {
-		drm_dbg_kms(&dev_priv->drm,
-			    "No PSR2 HW tracking in the platform\n");
-		return false;
+	if (HAS_PSR2_SEL_FETCH(dev_priv)) {
+		if (!intel_psr2_sel_fetch_config_valid(intel_dp, crtc_state) &&
+		    !HAS_PSR_HW_TRACKING(dev_priv)) {
+			drm_dbg_kms(&dev_priv->drm,
+				    "PSR2 not enabled, selective fetch not valid and no HW tracking available\n");
+			return false;
+		}
 	}
 
-	if (crtc_hdisplay > psr_max_h || crtc_vdisplay > psr_max_v) {
+	if (!crtc_state->enable_psr2_sel_fetch &&
+	    (crtc_hdisplay > psr_max_h || crtc_vdisplay > psr_max_v)) {
 		drm_dbg_kms(&dev_priv->drm,
 			    "PSR2 not enabled, resolution %dx%d > max supported %dx%d\n",
 			    crtc_hdisplay, crtc_vdisplay,
···
 		val |= EXITLINE_ENABLE;
 		intel_de_write(dev_priv, EXITLINE(cpu_transcoder), val);
 	}
+
+	if (HAS_PSR_HW_TRACKING(dev_priv))
+		intel_de_rmw(dev_priv, CHICKEN_PAR1_1, IGNORE_PSR2_HW_TRACKING,
+			     dev_priv->psr.psr2_sel_fetch_enabled ?
+			     IGNORE_PSR2_HW_TRACKING : 0);
 }
 
 static void intel_psr_enable_locked(struct drm_i915_private *dev_priv,
···
 	/* DC5/DC6 requires at least 6 idle frames */
 	val = usecs_to_jiffies(intel_get_frame_time_us(crtc_state) * 6);
 	dev_priv->psr.dc3co_exit_delay = val;
+	dev_priv->psr.psr2_sel_fetch_enabled = crtc_state->enable_psr2_sel_fetch;
 
 	/*
 	 * If a PSR error happened and the driver is reloaded, the EDP_PSR_IIR
···
 		 * on older gens so doing the manual exit instead.
 		 */
 		intel_psr_exit(dev_priv);
+}
+
+void intel_psr2_program_trans_man_trk_ctl(const struct intel_crtc_state *crtc_state)
+{
+	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	struct i915_psr *psr = &dev_priv->psr;
+
+	if (!HAS_PSR2_SEL_FETCH(dev_priv) ||
+	    !crtc_state->enable_psr2_sel_fetch)
+		return;
+
+	intel_de_write(dev_priv, PSR2_MAN_TRK_CTL(psr->transcoder),
+		       crtc_state->psr2_man_track_ctl);
+}
+
+void intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
+				 struct intel_crtc *crtc)
+{
+	struct intel_crtc_state *crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
+
+	if (!crtc_state->enable_psr2_sel_fetch)
+		return;
+
+	crtc_state->psr2_man_track_ctl = PSR2_MAN_TRK_CTL_ENABLE |
+					 PSR2_MAN_TRK_CTL_SF_SINGLE_FULL_FRAME;
 }
 
 /**

drivers/gpu/drm/i915/display/intel_psr.h

···
 struct drm_i915_private;
 struct intel_crtc_state;
 struct intel_dp;
+struct intel_crtc;
+struct intel_atomic_state;
 
 #define CAN_PSR(dev_priv) (HAS_PSR(dev_priv) && dev_priv->psr.sink_support)
 void intel_psr_init_dpcd(struct intel_dp *intel_dp);
···
 			    struct drm_connector_state *old_state,
 			    struct drm_connector_state *new_state);
 void intel_psr_set_force_mode_changed(struct intel_dp *intel_dp);
+void intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
+				 struct intel_crtc *crtc);
+void intel_psr2_program_trans_man_trk_ctl(const struct intel_crtc_state *crtc_state);
 
 #endif /* __INTEL_PSR_H__ */

drivers/gpu/drm/i915/i915_drv.h

···
 	bool link_standby;
 	bool colorimetry_support;
 	bool psr2_enabled;
+	bool psr2_sel_fetch_enabled;
 	u8 sink_sync_latency;
 	ktime_t last_entry_attempt;
 	ktime_t last_exit;
···
 #define HAS_PSR(dev_priv)		 (INTEL_INFO(dev_priv)->display.has_psr)
 #define HAS_PSR_HW_TRACKING(dev_priv) \
 	(INTEL_INFO(dev_priv)->display.has_psr_hw_tracking)
+#define HAS_PSR2_SEL_FETCH(dev_priv)	 (INTEL_GEN(dev_priv) >= 12)
 #define HAS_TRANSCODER(dev_priv, trans)	 ((INTEL_INFO(dev_priv)->cpu_transcoder_mask & BIT(trans)) != 0)
 
 #define HAS_RC6(dev_priv)		 (INTEL_INFO(dev_priv)->has_rc6)

drivers/gpu/drm/i915/i915_params.c

···
 	"is helpful to detect if PSR issues are related to bad values set in "
 	" VBT. (0=use VBT parameters, 1=use safest parameters)");
 
+i915_param_named_unsafe(enable_psr2_sel_fetch, bool, 0400,
+	"Enable PSR2 selective fetch "
+	"(0=disabled, 1=enabled) "
+	"Default: 0");
+
 i915_param_named_unsafe(force_probe, charp, 0400,
 	"Force probe the driver for specified devices. "
 	"See CONFIG_DRM_I915_FORCE_PROBE for details.");

drivers/gpu/drm/i915/i915_params.h

···
 	param(int, enable_fbc, -1, 0600) \
 	param(int, enable_psr, -1, 0600) \
 	param(bool, psr_safest_params, false, 0600) \
+	param(bool, enable_psr2_sel_fetch, false, 0600) \
 	param(int, disable_power_well, -1, 0400) \
 	param(int, enable_ips, 1, 0600) \
 	param(int, invert_brightness, 0, 0600) \