[Intel-gfx] [PATCH 5/9] drm/i915/dmc: extract function to parse package_header

[Srivatsa, Anusha]

>-----Original Message-----
>From: De Marchi, Lucas
>Sent: Friday, June 7, 2019 2:12 AM
>To: intel-gfx at lists.freedesktop.org
>Cc: Vivi, Rodrigo <rodrigo.vivi at intel.com>; Srivatsa, Anusha
><anusha.srivatsa at intel.com>; De Marchi, Lucas <lucas.demarchi at intel.com>
>Subject: [PATCH 5/9] drm/i915/dmc: extract function to parse package_header
>
>Like parse_csr_fw_css() this parses the package_header from firmware and saves
>the relevant fields in the csr struct. In this function we also lookup the fw_info we
>are interested in.
>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
>Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
>---
> drivers/gpu/drm/i915/intel_csr.c | 117 +++++++++++++++++--------------
> 1 file changed, 66 insertions(+), 51 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
>index 79732075f008..db5772616a4f 100644
>--- a/drivers/gpu/drm/i915/intel_csr.c
>+++ b/drivers/gpu/drm/i915/intel_csr.c
>@@ -332,6 +332,64 @@ static u32 find_dmc_fw_offset(const struct
>intel_fw_info *fw_info,
> 	return dmc_offset;
> }
>
>+static u32
>+parse_csr_fw_package(struct intel_csr *csr,
>+		     const struct intel_package_header *package_header,
>+		     const struct stepping_info *si,
>+		     size_t rem_size)
>+{
>+	u32 package_size = sizeof(struct intel_package_header);
>+	u32 num_entries, max_entries, dmc_offset;
>+	const struct intel_fw_info *fw_info;
>+
>+	if (rem_size < package_size)
>+		goto error_truncated;
>+
>+	if (package_header->header_ver == 1) {
>+		max_entries = PACKAGE_MAX_FW_INFO_ENTRIES;
>+	} else if (package_header->header_ver == 2) {
>+		max_entries = PACKAGE_V2_MAX_FW_INFO_ENTRIES;
>+	} else {
>+		DRM_ERROR("DMC firmware has unknown header version
>%u\n",
>+			  package_header->header_ver);
>+		return 0;
>+	}
>+
>+	/*
>+	 * We should always have space for max_entries,
>+	 * even if not all are used
>+	 */
>+	package_size += max_entries * sizeof(struct intel_fw_info);
>+	if (rem_size < package_size)
>+		goto error_truncated;
>+
>+	if (package_header->header_len * 4 != package_size) {
>+		DRM_ERROR("DMC firmware has wrong package header length "
>+			  "(%u bytes)\n", package_size);
>+		return 0;
>+	}
>+
>+	num_entries = package_header->num_entries;
>+	if (WARN_ON(package_header->num_entries > max_entries))
>+		num_entries = max_entries;
>+
>+	fw_info = (const struct intel_fw_info *)
>+		((u8 *)package_header + sizeof(*package_header));
>+	dmc_offset = find_dmc_fw_offset(fw_info, num_entries, si);
>+	if (dmc_offset == CSR_DEFAULT_FW_OFFSET) {
>+		DRM_ERROR("DMC firmware not supported for %c stepping\n",
>+			  si->stepping);
>+		return 0;
>+	}
>+
>+	/* dmc_offset is in dwords */
>+	return package_size + dmc_offset * 4;
>+
>+error_truncated:
>+	DRM_ERROR("Truncated DMC firmware, refusing.\n");
>+	return 0;
>+}
>+
> /* Return number of bytes parsed or 0 on error */  static u32
>parse_csr_fw_css(struct intel_csr *csr,
> 			    struct intel_css_header *css_header, @@ -374,7
>+432,7 @@ static u32 *parse_csr_fw(struct drm_i915_private *dev_priv,
> 	struct intel_dmc_header *dmc_header;
> 	struct intel_csr *csr = &dev_priv->csr;
> 	const struct stepping_info *si = intel_get_stepping_info(dev_priv);
>-	u32 dmc_offset, num_entries, max_entries, readcount = 0, nbytes;
>+	u32 readcount = 0, nbytes;
> 	u32 i, r;
> 	u32 *dmc_payload;
> 	size_t fsize;
>@@ -389,59 +447,16 @@ static u32 *parse_csr_fw(struct drm_i915_private
>*dev_priv,
> 		return NULL;
>
> 	readcount += r;
>-	fsize = readcount +
>-		sizeof(struct intel_package_header) +
>-		sizeof(struct intel_dmc_header);
>-	if (fsize > fw->size)
>-		goto error_truncated;
>-
>-	/* Extract Package Header information*/
>-	package_header = (struct intel_package_header *)
>-		&fw->data[readcount];
>-
>-	readcount += sizeof(struct intel_package_header);
>-
>-	if (package_header->header_ver == 1) {
>-		max_entries = PACKAGE_MAX_FW_INFO_ENTRIES;
>-	} else if (package_header->header_ver == 2) {
>-		max_entries = PACKAGE_V2_MAX_FW_INFO_ENTRIES;
>-	} else {
>-		DRM_ERROR("DMC firmware has unknown header version
>%u\n",
>-			  package_header->header_ver);
>-		return NULL;
>-	}
>-
>-	if (package_header->header_len * 4 !=
>-	    sizeof(struct intel_package_header) +
>-	    max_entries * sizeof(struct intel_fw_info)) {
>-		DRM_ERROR("DMC firmware has wrong package header length "
>-			  "(%u bytes)\n", package_header->header_len * 4);
>-		return NULL;
>-	}
>-
>-	num_entries = package_header->num_entries;
>-	if (WARN_ON(package_header->num_entries > max_entries))
>-		num_entries = max_entries;
>-
>-	fsize += max_entries * sizeof(struct intel_fw_info);
>-	if (fsize > fw->size)
>-		goto error_truncated;
>
>-	dmc_offset = find_dmc_fw_offset((struct intel_fw_info *)
>-					&fw->data[readcount], num_entries, si);
>-	if (dmc_offset == CSR_DEFAULT_FW_OFFSET) {
>-		DRM_ERROR("DMC firmware not supported for %c stepping\n",
>-			  si->stepping);
>+	/* Extract Package Header information */
>+	package_header = (struct intel_package_header *)&fw-
>>data[readcount];
>+	r = parse_csr_fw_package(csr, package_header, si, fw->size - readcount);
>+	if (!r)
> 		return NULL;
>-	}
>
>-	/* we always have space for max_entries, even if not all are used */
>-	readcount += max_entries * sizeof(struct intel_fw_info);
>-
>-	/* Convert dmc_offset into number of bytes. By default it is in dwords*/
>-	dmc_offset *= 4;
>-	readcount += dmc_offset;
>-	fsize += dmc_offset;
>+	readcount += r;
>+	fsize = readcount +
>+		sizeof(struct intel_dmc_header);
> 	if (fsize > fw->size)
> 		goto error_truncated;
>
>--
>2.21.0