[PATCH] drm/i915/display: Implement wa_14024400148

[Nemesa Garg]

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

Signed-off-by: Nemesa Garg <nemesa.g...@intel.com>
---
 drivers/gpu/drm/i915/display/intel_pmdemand.c | 27 +++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_pmdemand.c 
b/drivers/gpu/drm/i915/display/intel_pmdemand.c
index d22b5469672d..610d05b73b99 100644
--- a/drivers/gpu/drm/i915/display/intel_pmdemand.c
+++ b/drivers/gpu/drm/i915/display/intel_pmdemand.c
@@ -478,6 +478,22 @@ static bool intel_pmdemand_req_complete(struct 
intel_display *display)
                 XELPDP_PMDEMAND_REQ_ENABLE);
 }
 
+static void intel_pmdemand_poll(struct intel_display *display)
+{
+       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,
+                       "timeout within %ums (status 0x%08x)\n",
+                       timeout_ms, status);
+}
+
 static void intel_pmdemand_wait(struct intel_display *display)
 {
        if (!wait_event_timeout(display->pmdemand.waitqueue,
@@ -508,7 +524,11 @@ void intel_pmdemand_program_dbuf(struct intel_display 
*display,
        intel_de_rmw(display, XELPDP_INITIATE_PMDEMAND_REQUEST(1), 0,
                     XELPDP_PMDEMAND_REQ_ENABLE);
 
-       intel_pmdemand_wait(display);
+       /* Wa_14024400148 For lnl use polling method */
+       if (DISPLAY_VER(display) == 20)
+               intel_pmdemand_poll(display);
+       else
+               intel_pmdemand_wait(display);
 
 unlock:
        mutex_unlock(&display->pmdemand.lock);
@@ -617,7 +637,10 @@ intel_pmdemand_program_params(struct intel_display 
*display,
        intel_de_rmw(display, XELPDP_INITIATE_PMDEMAND_REQUEST(1), 0,
                     XELPDP_PMDEMAND_REQ_ENABLE);
 
-       intel_pmdemand_wait(display);
+       if (DISPLAY_VER(display) == 20)
+               intel_pmdemand_poll(display);
+       else
+               intel_pmdemand_wait(display);
 
 unlock:
        mutex_unlock(&display->pmdemand.lock);
-- 
2.25.1