On 4/22/2025 9:02 PM, Kahola, Mika wrote:
-----Original Message-----
From: Garg, Nemesa <[email protected]>
Sent: Wednesday, 16 April 2025 18.21
To: [email protected]; [email protected]; Kahola,
Mika
<[email protected]>
Cc: Garg, Nemesa <[email protected]>
Subject: [PATCH v2] drm/i915/display: Implement wa_14024400148
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 <[email protected]>
---
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 {
Maybe this else branch could be written as its own function as with if branch.
Anyway, this might be a topic for follow up patch.
Reviewed-by: Mika Kahola <[email protected]>
Thanks for the patch and review. Pushed to drm-intel-next.
Regards,
Ankit
+ 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
