[PATCH v2] drm/i915/display: Implement wa_14024400148

[Nemesa Garg]

Workaround recommend use polling method
for pm_demand to finish as to avoid timeout.

v2: Add polling method within pmdemand_wait.
    Update error message[Jani]	

Signed-off-by: Nemesa Garg <nemesa.garg at intel.com>
---
 drivers/gpu/drm/i915/display/intel_pmdemand.c | 31 ++++++++++++++++---
 1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_pmdemand.c b/drivers/gpu/drm/i915/display/intel_pmdemand.c
index d22b5469672d..1253376c7654 100644
--- a/drivers/gpu/drm/i915/display/intel_pmdemand.c
+++ b/drivers/gpu/drm/i915/display/intel_pmdemand.c
@@ -478,13 +478,34 @@ static bool intel_pmdemand_req_complete(struct intel_display *display)
 		 XELPDP_PMDEMAND_REQ_ENABLE);
 }
 
-static void intel_pmdemand_wait(struct intel_display *display)
+static void intel_pmdemand_poll(struct intel_display *display)
 {
-	if (!wait_event_timeout(display->pmdemand.waitqueue,
-				intel_pmdemand_req_complete(display),
-				msecs_to_jiffies_timeout(10)))
+	const unsigned int timeout_ms = 10;
+	u32 status;
+	int ret;
+
+	ret = intel_de_wait_custom(display, XELPDP_INITIATE_PMDEMAND_REQUEST(1),
+				   XELPDP_PMDEMAND_REQ_ENABLE, 0,
+				   50, timeout_ms, &status);
+
+	if (ret == -ETIMEDOUT)
 		drm_err(display->drm,
-			"timed out waiting for Punit PM Demand Response\n");
+			"timed out waiting for Punit PM Demand Response within %ums (status 0x%08x)\n",
+			timeout_ms, status);
+}
+
+static void intel_pmdemand_wait(struct intel_display *display)
+{
+	/* Wa_14024400148 For lnl use polling method */
+	if (DISPLAY_VER(display) == 20) {
+		intel_pmdemand_poll(display);
+	} else {
+		if (!wait_event_timeout(display->pmdemand.waitqueue,
+					intel_pmdemand_req_complete(display),
+					msecs_to_jiffies_timeout(10)))
+			drm_err(display->drm,
+				"timed out waiting for Punit PM Demand Response\n");
+	}
 }
 
 /* Required to be programmed during Display Init Sequences. */
-- 
2.25.1