[Intel-gfx] [PATCH] drm/i915/guc: Move firmware size check out of generic code

[Michal Wajdeczko]

Checking GuC firmware size can be done in GuC specific code
right before DMA copy as it is unlikely to fail anyway.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_guc_loader.c | 14 +++++++++++---
 drivers/gpu/drm/i915/intel_uc_fw.c      |  8 --------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c b/drivers/gpu/drm/i915/intel_guc_loader.c
index c7a800a..f245aa5 100644
--- a/drivers/gpu/drm/i915/intel_guc_loader.c
+++ b/drivers/gpu/drm/i915/intel_guc_loader.c
@@ -198,6 +198,7 @@ static int guc_ucode_xfer_dma(struct drm_i915_private *dev_priv,
 	unsigned long offset;
 	struct sg_table *sg = vma->pages;
 	u32 status, rsa[UOS_RSA_SCRATCH_MAX_COUNT];
+	u32 size = guc_fw->header_size + guc_fw->ucode_size;
 	int i, ret = 0;
 
 	/* where RSA signature starts */
@@ -208,9 +209,16 @@ static int guc_ucode_xfer_dma(struct drm_i915_private *dev_priv,
 	for (i = 0; i < UOS_RSA_SCRATCH_MAX_COUNT; i++)
 		I915_WRITE(UOS_RSA_SCRATCH(i), rsa[i]);
 
-	/* The header plus uCode will be copied to WOPCM via DMA, excluding any
-	 * other components */
-	I915_WRITE(DMA_COPY_SIZE, guc_fw->header_size + guc_fw->ucode_size);
+	/*
+	 * The header plus uCode will be copied to WOPCM via DMA, excluding any
+	 * other components. Make sure that firmware fits there.
+	 */
+	if (unlikely(size > intel_guc_wopcm_size(dev_priv))) {
+		DRM_ERROR("GuC: Firmware is too large (%dB) to fit in WOPCM\n",
+			  size);
+		return -EFBIG;
+	}
+	I915_WRITE(DMA_COPY_SIZE, size);
 
 	/* Set the source address for the new blob */
 	offset = guc_ggtt_offset(vma) + guc_fw->header_offset;
diff --git a/drivers/gpu/drm/i915/intel_uc_fw.c b/drivers/gpu/drm/i915/intel_uc_fw.c
index 766b1cb..482115b 100644
--- a/drivers/gpu/drm/i915/intel_uc_fw.c
+++ b/drivers/gpu/drm/i915/intel_uc_fw.c
@@ -108,14 +108,6 @@ void intel_uc_fw_fetch(struct drm_i915_private *dev_priv,
 	 */
 	switch (uc_fw->type) {
 	case INTEL_UC_FW_TYPE_GUC:
-		/* Header and uCode will be loaded to WOPCM. Size of the two. */
-		size = uc_fw->header_size + uc_fw->ucode_size;
-
-		/* Top 32k of WOPCM is reserved (8K stack + 24k RC6 context). */
-		if (size > intel_guc_wopcm_size(dev_priv)) {
-			DRM_ERROR("Firmware is too large to fit in WOPCM\n");
-			goto fail;
-		}
 		uc_fw->major_ver_found = css->guc.sw_version >> 16;
 		uc_fw->minor_ver_found = css->guc.sw_version & 0xFFFF;
 		break;
-- 
2.7.4