[PATCH v2 3/5] drm/i915/irq: conditional HPD IRQ resets based on PME capability

[Vinod Govindapillai <vinod.govindapillai@intel.com>]

If a device supports generating PME from HPDs, resetting HPD IRQs
will be counter productive as HPDs itself will be lost. During
suspend routines, all the IRQs are reset. So if the device is
capable of generating PME rom HPDs, keep the HPD related IRQs from
reset based on the PME capability of the device on a target power
state. PME capability will be assessed and updated separately.

Bspec: 52979, 52980, 68857, 68867, 68970
Assisted-by: GitHub_Copilot:claude-opus-5
Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
---
 .../gpu/drm/i915/display/intel_display_irq.c  | 20 ++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.c b/drivers/gpu/drm/i915/display/intel_display_irq.c
index a59b75830bd1..fc50b19d5ddf 100644
--- a/drivers/gpu/drm/i915/display/intel_display_irq.c
+++ b/drivers/gpu/drm/i915/display/intel_display_irq.c
@@ -22,6 +22,7 @@
 #include "intel_fdi_regs.h"
 #include "intel_fifo_underrun.h"
 #include "intel_gmbus.h"
+#include "intel_hotplug.h"
 #include "intel_hotplug_irq.h"
 #include "intel_lpe_audio.h"
 #include "intel_parent.h"
@@ -2217,8 +2218,11 @@ static void gen11_display_irq_reset(struct intel_display *display)
 	enum pipe pipe;
 	u32 trans_mask = BIT(TRANSCODER_A) | BIT(TRANSCODER_B) |
 		BIT(TRANSCODER_C) | BIT(TRANSCODER_D);
+	/* If HPD can generate PME, we don't want to reset HPD related IRQs */
+	bool keep_hpd = intel_hpd_can_generate_pme(display);
 
-	intel_de_write(display, GEN11_DISPLAY_INT_CTL, 0);
+	if (!keep_hpd)
+		intel_de_write(display, GEN11_DISPLAY_INT_CTL, 0);
 
 	if (DISPLAY_VER(display) >= 12) {
 		enum transcoder trans;
@@ -2250,13 +2254,15 @@ static void gen11_display_irq_reset(struct intel_display *display)
 	irq_reset(display, GEN8_DE_PORT_IRQ_REGS);
 	irq_reset(display, GEN8_DE_MISC_IRQ_REGS);
 
-	if (DISPLAY_VER(display) >= 14)
-		irq_reset(display, PICAINTERRUPT_IRQ_REGS);
-	else
-		irq_reset(display, GEN11_DE_HPD_IRQ_REGS);
+	if (!keep_hpd) {
+		if (DISPLAY_VER(display) >= 14)
+			irq_reset(display, PICAINTERRUPT_IRQ_REGS);
+		else
+			irq_reset(display, GEN11_DE_HPD_IRQ_REGS);
 
-	if (INTEL_PCH_TYPE(display) >= PCH_ICP)
-		irq_reset(display, SDE_IRQ_REGS);
+		if (INTEL_PCH_TYPE(display) >= PCH_ICP)
+			irq_reset(display, SDE_IRQ_REGS);
+	}
 }
 
 void gen8_irq_power_well_post_enable(struct intel_display *display,
-- 
2.43.0