drm/i915/psr: Apply underrun on PSR idle workaround

This patch is applying workaround for underrun on idle PSR HW issue
(Wa_16025596647) when PSR is getting enabled. It uses vblank enable/disable
status, DC5/6 enabled disabled and enabled pipes count information made
available.

This patch is also adding calls to dc5/dc6, vblank enable/disable and pipe
enable/disable notification functions as needed.
intel_psr_needs_block_dc_vblank is modified to get vblank enable/disable
notification on PSR capable system.

v2: use intel_dmc interface instead of directly writing dmc register

Bspec: 74151
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Link: https://lore.kernel.org/r/20250414100508.1208774-12-jouni.hogander@intel.com

5 files changed, 61 insertions, 48 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 9c966bbbfd31..6bd55fd9dff8 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -6659,6 +6659,8 @@ static void intel_enable_crtc(struct intel_atomic_state *state,
 		intel_crtc_update_active_timings(pipe_crtc_state, false);
 	}
 
+	intel_psr_notify_pipe_change(state, crtc, true);
+
 	display->funcs.display->crtc_enable(state, crtc);
 
 	/* vblanks work again, re-enable pipe CRC. */
@@ -6778,6 +6780,8 @@ static void intel_old_crtc_state_disables(struct intel_atomic_state *state,
 					 intel_crtc_joined_pipe_mask(old_crtc_state))
 		intel_crtc_disable_pipe_crc(pipe_crtc);
 
+	intel_psr_notify_pipe_change(state, crtc, false);
+
 	display->funcs.display->crtc_disable(state, crtc);
 
 	for_each_intel_crtc_in_pipe_mask(display->drm, pipe_crtc,
diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.c b/drivers/gpu/drm/i915/display/intel_display_driver.c
index eb3ae05d1569..69678e758c46 100644
--- a/drivers/gpu/drm/i915/display/intel_display_driver.c
+++ b/drivers/gpu/drm/i915/display/intel_display_driver.c
@@ -54,6 +54,7 @@
 #include "intel_plane_initial.h"
 #include "intel_pmdemand.h"
 #include "intel_pps.h"
+#include "intel_psr.h"
 #include "intel_quirks.h"
 #include "intel_vga.h"
 #include "intel_wm.h"
@@ -226,6 +227,8 @@ int intel_display_driver_probe_noirq(struct intel_display *display)
 	if (ret)
 		goto cleanup_bios;
 
+	intel_psr_dc5_dc6_wa_init(display);
+
 	/* FIXME: completely on the wrong abstraction layer */
 	ret = intel_power_domains_init(display);
 	if (ret < 0)
diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.c b/drivers/gpu/drm/i915/display/intel_display_irq.c
index 2e34af6e40f0..ab1d96924494 100644
--- a/drivers/gpu/drm/i915/display/intel_display_irq.c
+++ b/drivers/gpu/drm/i915/display/intel_display_irq.c
@@ -1704,14 +1704,7 @@ static void intel_display_vblank_dc_work(struct work_struct *work)
 		container_of(work, typeof(*display), irq.vblank_dc_work);
 	int vblank_wa_num_pipes = READ_ONCE(display->irq.vblank_wa_num_pipes);
 
-	/*
-	 * NOTE: intel_display_power_set_target_dc_state is used only by PSR
-	 * code for DC3CO handling. DC3CO target state is currently disabled in
-	 * PSR code. If DC3CO is taken into use we need take that into account
-	 * here as well.
-	 */
-	intel_display_power_set_target_dc_state(display, vblank_wa_num_pipes ? DC_STATE_DISABLE :
-						DC_STATE_EN_UPTO_DC6);
+	intel_psr_notify_vblank_enable_disable(display, vblank_wa_num_pipes);
 }
 
 int bdw_enable_vblank(struct drm_crtc *_crtc)
diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.c b/drivers/gpu/drm/i915/display/intel_display_power_well.c
index b9b4359751cc..563a468f4537 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power_well.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power_well.c
@@ -25,6 +25,7 @@
 #include "intel_hotplug.h"
 #include "intel_pcode.h"
 #include "intel_pps.h"
+#include "intel_psr.h"
 #include "intel_tc.h"
 #include "intel_vga.h"
 #include "skl_watermark.h"
@@ -760,6 +761,9 @@ void gen9_set_dc_state(struct intel_display *display, u32 state)
 			     state & ~power_domains->allowed_dc_mask))
 		state &= power_domains->allowed_dc_mask;
 
+	if (!power_domains->initializing)
+		intel_psr_notify_dc5_dc6(display);
+
 	val = intel_de_read(display, DC_STATE_EN);
 	mask = gen9_dc_mask(display);
 	drm_dbg_kms(display->drm, "Setting DC state from %02x to %02x\n",
diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 5e9277ccfe84..ae60a9d346cd 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -907,6 +907,18 @@ static u8 psr_compute_idle_frames(struct intel_dp *intel_dp)
 	return idle_frames;
 }
 
+static bool is_dc5_dc6_blocked(struct intel_dp *intel_dp)
+{
+	struct intel_display *display = to_intel_display(intel_dp);
+	u32 current_dc_state = intel_display_power_get_current_dc_state(display);
+	struct drm_vblank_crtc *vblank = &display->drm->vblank[intel_dp->psr.pipe];
+
+	return (current_dc_state != DC_STATE_EN_UPTO_DC5 &&
+		current_dc_state != DC_STATE_EN_UPTO_DC6) ||
+		intel_dp->psr.active_non_psr_pipes ||
+		READ_ONCE(vblank->enabled);
+}
+
 static void hsw_activate_psr1(struct intel_dp *intel_dp)
 {
 	struct intel_display *display = to_intel_display(intel_dp);
@@ -935,6 +947,14 @@ static void hsw_activate_psr1(struct intel_dp *intel_dp)
 
 	intel_de_rmw(display, psr_ctl_reg(display, cpu_transcoder),
 		     ~EDP_PSR_RESTORE_PSR_ACTIVE_CTX_MASK, val);
+
+	/* Wa_16025596647 */
+	if ((DISPLAY_VER(display) == 20 ||
+	     IS_DISPLAY_VERx100_STEP(display, 3000, STEP_A0, STEP_B0)) &&
+	    is_dc5_dc6_blocked(intel_dp))
+		intel_dmc_start_pkgc_exit_at_start_of_undelayed_vblank(display,
+								       intel_dp->psr.pipe,
+								       true);
 }
 
 static u32 intel_psr2_get_tp_time(struct intel_dp *intel_dp)
@@ -1016,8 +1036,16 @@ static void hsw_activate_psr2(struct intel_dp *intel_dp)
 	enum transcoder cpu_transcoder = intel_dp->psr.transcoder;
 	u32 val = EDP_PSR2_ENABLE;
 	u32 psr_val = 0;
+	u8 idle_frames;
 
-	val |= EDP_PSR2_IDLE_FRAMES(psr_compute_idle_frames(intel_dp));
+	/* Wa_16025596647 */
+	if ((DISPLAY_VER(display) == 20 ||
+	     IS_DISPLAY_VERx100_STEP(display, 3000, STEP_A0, STEP_B0)) &&
+	    is_dc5_dc6_blocked(intel_dp))
+		idle_frames = 0;
+	else
+		idle_frames = psr_compute_idle_frames(intel_dp);
+	val |= EDP_PSR2_IDLE_FRAMES(idle_frames);
 
 	if (DISPLAY_VER(display) < 14 && !display->platform.alderlake_p)
 		val |= EDP_SU_TRACK_ENABLE;
@@ -2090,6 +2118,12 @@ static void intel_psr_exit(struct intel_dp *intel_dp)
 
 		drm_WARN_ON(display->drm, !(val & EDP_PSR2_ENABLE));
 	} else {
+		if (DISPLAY_VER(display) == 20 ||
+		    IS_DISPLAY_VERx100_STEP(display, 3000, STEP_A0, STEP_B0))
+			intel_dmc_start_pkgc_exit_at_start_of_undelayed_vblank(display,
+								       intel_dp->psr.pipe,
+								       false);
+
 		val = intel_de_rmw(display,
 				   psr_ctl_reg(display, cpu_transcoder),
 				   EDP_PSR_ENABLE, 0);
@@ -2302,6 +2336,7 @@ out:
 bool intel_psr_needs_block_dc_vblank(const struct intel_crtc_state *crtc_state)
 {
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+	struct intel_display *display = to_intel_display(crtc_state);
 	struct intel_encoder *encoder;
 
 	for_each_encoder_on_crtc(crtc->base.dev, &crtc->base, encoder) {
@@ -2312,8 +2347,15 @@ bool intel_psr_needs_block_dc_vblank(const struct intel_crtc_state *crtc_state)
 
 		intel_dp = enc_to_intel_dp(encoder);
 
-		if (intel_dp_is_edp(intel_dp) &&
-		    CAN_PANEL_REPLAY(intel_dp))
+		if (!intel_dp_is_edp(intel_dp))
+			continue;
+
+		if (CAN_PANEL_REPLAY(intel_dp))
+			return true;
+
+		if ((DISPLAY_VER(display) == 20 ||
+		     IS_DISPLAY_VERx100_STEP(display, 3000, STEP_A0, STEP_B0)) &&
+		    CAN_PSR(intel_dp))
 			return true;
 	}
 
@@ -3643,44 +3685,9 @@ void intel_psr_unlock(const struct intel_crtc_state *crtc_state)
 }
 
 /* Wa_16025596647 */
-static void psr1_apply_underrun_on_idle_wa_locked(struct intel_dp *intel_dp,
-						  bool dc5_dc6_blocked)
-{
-	struct intel_display *display = to_intel_display(intel_dp);
-	u32 val;
-
-	if (dc5_dc6_blocked)
-		val = DMC_EVT_CTL_ENABLE | DMC_EVT_CTL_RECURRING |
-			REG_FIELD_PREP(DMC_EVT_CTL_TYPE_MASK,
-				       DMC_EVT_CTL_TYPE_EDGE_0_1) |
-			REG_FIELD_PREP(DMC_EVT_CTL_EVENT_ID_MASK,
-				       DMC_EVT_CTL_EVENT_ID_VBLANK_A);
-	else
-		val = REG_FIELD_PREP(DMC_EVT_CTL_EVENT_ID_MASK,
-				     DMC_EVT_CTL_EVENT_ID_FALSE) |
-			REG_FIELD_PREP(DMC_EVT_CTL_TYPE_MASK,
-				       DMC_EVT_CTL_TYPE_EDGE_0_1);
-
-	intel_de_write(display, MTL_PIPEDMC_EVT_CTL_4(intel_dp->psr.pipe),
-		       val);
-}
-
-/* Wa_16025596647 */
-static bool is_dc5_dc6_blocked(struct intel_dp *intel_dp)
-{
-	struct intel_display *display = to_intel_display(intel_dp);
-	u32 current_dc_state = intel_display_power_get_current_dc_state(display);
-	struct drm_vblank_crtc *vblank = &display->drm->vblank[intel_dp->psr.pipe];
-
-	return (current_dc_state != DC_STATE_EN_UPTO_DC5 &&
-		current_dc_state != DC_STATE_EN_UPTO_DC6) ||
-		intel_dp->psr.active_non_psr_pipes ||
-		READ_ONCE(vblank->enabled);
-}
-
-/* Wa_16025596647 */
 static void intel_psr_apply_underrun_on_idle_wa_locked(struct intel_dp *intel_dp)
 {
+	struct intel_display *display = to_intel_display(intel_dp);
 	bool dc5_dc6_blocked;
 
 	if (!intel_dp->psr.active)
@@ -3692,7 +3699,9 @@ static void intel_psr_apply_underrun_on_idle_wa_locked(struct intel_dp *intel_dp
 		psr2_program_idle_frames(intel_dp, dc5_dc6_blocked ? 0 :
 					 psr_compute_idle_frames(intel_dp));
 	else
-		psr1_apply_underrun_on_idle_wa_locked(intel_dp, dc5_dc6_blocked);
+		intel_dmc_start_pkgc_exit_at_start_of_undelayed_vblank(display,
+								       intel_dp->psr.pipe,
+								       dc5_dc6_blocked);
 }
 
 static void psr_dc5_dc6_wa_work(struct work_struct *work)