3 files changed, 59 insertions, 28 deletions

diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index a05623a8c163..927e1370e2a0 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -422,12 +422,68 @@ mask_err:
 	return err;
 }
 
+static bool verify_lmem_ready(struct xe_gt *gt)
+{
+	u32 val = xe_mmio_read32(gt, GU_CNTL) & LMEM_INIT;
+
+	return !!val;
+}
+
+static int wait_for_lmem_ready(struct xe_device *xe)
+{
+	struct xe_gt *gt = xe_root_mmio_gt(xe);
+	unsigned long timeout, start;
+
+	if (!IS_DGFX(xe))
+		return 0;
+
+	if (IS_SRIOV_VF(xe))
+		return 0;
+
+	if (verify_lmem_ready(gt))
+		return 0;
+
+	drm_dbg(&xe->drm, "Waiting for lmem initialization\n");
+
+	start = jiffies;
+	timeout = start + msecs_to_jiffies(60 * 1000); /* 60 sec! */
+
+	do {
+		if (signal_pending(current))
+			return -EINTR;
+
+		/*
+		 * The boot firmware initializes local memory and
+		 * assesses its health. If memory training fails,
+		 * the punit will have been instructed to keep the GT powered
+		 * down.we won't be able to communicate with it
+		 *
+		 * If the status check is done before punit updates the register,
+		 * it can lead to the system being unusable.
+		 * use a timeout and defer the probe to prevent this.
+		 */
+		if (time_after(jiffies, timeout)) {
+			drm_dbg(&xe->drm, "lmem not initialized by firmware\n");
+			return -EPROBE_DEFER;
+		}
+
+		msleep(20);
+
+	} while (!verify_lmem_ready(gt));
+
+	drm_dbg(&xe->drm, "lmem ready after %ums",
+		jiffies_to_msecs(jiffies - start));
+
+	return 0;
+}
+
 /**
  * xe_device_probe_early: Device early probe
  * @xe: xe device instance
  *
  * Initialize MMIO resources that don't require any
- * knowledge about tile count. Also initialize pcode
+ * knowledge about tile count. Also initialize pcode and
+ * check vram initialization on root tile.
  *
  * Return: 0 on success, error code on failure
  */
@@ -441,11 +497,11 @@ int xe_device_probe_early(struct xe_device *xe)
 
 	xe_sriov_probe_early(xe);
 
-	err = xe_mmio_verify_vram(xe);
+	err = xe_pcode_probe_early(xe);
 	if (err)
 		return err;
 
-	err = xe_pcode_probe_early(xe);
+	err = wait_for_lmem_ready(xe);
 	if (err)
 		return err;
 
diff --git a/drivers/gpu/drm/xe/xe_mmio.c b/drivers/gpu/drm/xe/xe_mmio.c
index d66da1a9f165..334637511e75 100644
--- a/drivers/gpu/drm/xe/xe_mmio.c
+++ b/drivers/gpu/drm/xe/xe_mmio.c
@@ -420,30 +420,6 @@ int xe_mmio_init(struct xe_device *xe)
 	return drmm_add_action_or_reset(&xe->drm, mmio_fini, xe);
 }
 
-int xe_mmio_verify_vram(struct xe_device *xe)
-{
-	struct xe_gt *gt = xe_root_mmio_gt(xe);
-
-	if (!IS_DGFX(xe))
-		return 0;
-
-	if (IS_SRIOV_VF(xe))
-		return 0;
-
-	/*
-	 * The boot firmware initializes local memory and assesses its health.
-	 * If memory training fails, the punit will have been instructed to
-	 * keep the GT powered down; we won't be able to communicate with it
-	 * and we should not continue with driver initialization.
-	 */
-	if (!(xe_mmio_read32(gt, GU_CNTL) & LMEM_INIT)) {
-		drm_err(&xe->drm, "VRAM not initialized by firmware\n");
-		return -ENODEV;
-	}
-
-	return 0;
-}
-
 u8 xe_mmio_read8(struct xe_gt *gt, struct xe_reg reg)
 {
 	struct xe_tile *tile = gt_to_tile(gt);
diff --git a/drivers/gpu/drm/xe/xe_mmio.h b/drivers/gpu/drm/xe/xe_mmio.h
index b1680c4a14fb..a3cd7b3036c7 100644
--- a/drivers/gpu/drm/xe/xe_mmio.h
+++ b/drivers/gpu/drm/xe/xe_mmio.h
@@ -21,7 +21,6 @@ struct xe_device;
 #define LMEM_BAR		2
 
 int xe_mmio_init(struct xe_device *xe);
-int xe_mmio_verify_vram(struct xe_device *xe);
 void xe_mmio_probe_tiles(struct xe_device *xe);
 
 u8 xe_mmio_read8(struct xe_gt *gt, struct xe_reg reg);