drm/i915/dmc: extract function to parse dmc_header

Complete the extraction of functions to parse specific parts of the
firmware. The return of the function parse_csr_fw() is now redundant
since it already sets the dmc_payload field. Changing it is left for
later to avoid noise in the commit.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190607091230.1489-7-lucas.demarchi@intel.com

diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
index a0188f87904f918196b740ecbbdd5e7ff85d0273..4622f7f32a23fc97d9d6200f2e833223858b6da2 100644 (file)
--- a/drivers/gpu/drm/i915/intel_csr.c
+++ b/drivers/gpu/drm/i915/intel_csr.c
@@ -332,6 +332,74 @@ static u32 find_dmc_fw_offset(const struct intel_fw_info *fw_info,
        return dmc_offset;
 }
 
+static u32 parse_csr_fw_dmc(struct intel_csr *csr,
+                           const struct intel_dmc_header *dmc_header,
+                           size_t rem_size)
+{
+       unsigned int i, payload_size;
+       u32 r;
+       u8 *payload;
+
+       if (rem_size < sizeof(struct intel_dmc_header))
+               goto error_truncated;
+
+       if (sizeof(struct intel_dmc_header) != dmc_header->header_len) {
+               DRM_ERROR("DMC firmware has wrong dmc header length "
+                         "(%u bytes)\n",
+                         (dmc_header->header_len));
+               return 0;
+       }
+
+       /* Cache the dmc header info. */
+       if (dmc_header->mmio_count > ARRAY_SIZE(csr->mmioaddr)) {
+               DRM_ERROR("DMC firmware has wrong mmio count %u\n",
+                         dmc_header->mmio_count);
+               return 0;
+       }
+
+       csr->mmio_count = dmc_header->mmio_count;
+       for (i = 0; i < dmc_header->mmio_count; i++) {
+               if (dmc_header->mmioaddr[i] < CSR_MMIO_START_RANGE ||
+                   dmc_header->mmioaddr[i] > CSR_MMIO_END_RANGE) {
+                       DRM_ERROR("DMC firmware has wrong mmio address 0x%x\n",
+                                 dmc_header->mmioaddr[i]);
+                       return 0;
+               }
+               csr->mmioaddr[i] = _MMIO(dmc_header->mmioaddr[i]);
+               csr->mmiodata[i] = dmc_header->mmiodata[i];
+       }
+
+       rem_size -= dmc_header->header_len;
+
+       /* fw_size is in dwords, so multiplied by 4 to convert into bytes. */
+       payload_size = dmc_header->fw_size * 4;
+       if (rem_size < payload_size)
+               goto error_truncated;
+
+       if (payload_size > csr->max_fw_size) {
+               DRM_ERROR("DMC FW too big (%u bytes)\n", payload_size);
+               return 0;
+       }
+       csr->dmc_fw_size = dmc_header->fw_size;
+
+       csr->dmc_payload = kmalloc(payload_size, GFP_KERNEL);
+       if (!csr->dmc_payload) {
+               DRM_ERROR("Memory allocation failed for dmc payload\n");
+               return 0;
+       }
+
+       r = sizeof(struct intel_dmc_header);
+       payload = (u8 *)(dmc_header) + r;
+       memcpy(csr->dmc_payload, payload, payload_size);
+       r += payload_size;
+
+       return r;
+
+error_truncated:
+       DRM_ERROR("Truncated DMC firmware, refusing.\n");
+       return 0;
+}
+
 static u32
 parse_csr_fw_package(struct intel_csr *csr,
                     const struct intel_package_header *package_header,
@@ -432,10 +500,8 @@ 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 readcount = 0, nbytes;
-       u32 i, r;
-       u32 *dmc_payload;
-       size_t fsize;
+       u32 readcount = 0;
+       u32 r;
 
        if (!fw)
                return NULL;
@@ -455,62 +521,14 @@ static u32 *parse_csr_fw(struct drm_i915_private *dev_priv,
                return NULL;
 
        readcount += r;
-       fsize = readcount +
-               sizeof(struct intel_dmc_header);
-       if (fsize > fw->size)
-               goto error_truncated;
 
-       /* Extract dmc_header information. */
+       /* Extract dmc_header information */
        dmc_header = (struct intel_dmc_header *)&fw->data[readcount];
-       if (sizeof(struct intel_dmc_header) != (dmc_header->header_len)) {
-               DRM_ERROR("DMC firmware has wrong dmc header length "
-                         "(%u bytes)\n",
-                         (dmc_header->header_len));
-               return NULL;
-       }
-       readcount += sizeof(struct intel_dmc_header);
-
-       /* Cache the dmc header info. */
-       if (dmc_header->mmio_count > ARRAY_SIZE(csr->mmioaddr)) {
-               DRM_ERROR("DMC firmware has wrong mmio count %u\n",
-                         dmc_header->mmio_count);
-               return NULL;
-       }
-       csr->mmio_count = dmc_header->mmio_count;
-       for (i = 0; i < dmc_header->mmio_count; i++) {
-               if (dmc_header->mmioaddr[i] < CSR_MMIO_START_RANGE ||
-                   dmc_header->mmioaddr[i] > CSR_MMIO_END_RANGE) {
-                       DRM_ERROR("DMC firmware has wrong mmio address 0x%x\n",
-                                 dmc_header->mmioaddr[i]);
-                       return NULL;
-               }
-               csr->mmioaddr[i] = _MMIO(dmc_header->mmioaddr[i]);
-               csr->mmiodata[i] = dmc_header->mmiodata[i];
-       }
-
-       /* fw_size is in dwords, so multiplied by 4 to convert into bytes. */
-       nbytes = dmc_header->fw_size * 4;
-       fsize += nbytes;
-       if (fsize > fw->size)
-               goto error_truncated;
-
-       if (nbytes > csr->max_fw_size) {
-               DRM_ERROR("DMC FW too big (%u bytes)\n", nbytes);
-               return NULL;
-       }
-       csr->dmc_fw_size = dmc_header->fw_size;
-
-       dmc_payload = kmalloc(nbytes, GFP_KERNEL);
-       if (!dmc_payload) {
-               DRM_ERROR("Memory allocation failed for dmc payload\n");
+       r = parse_csr_fw_dmc(csr, dmc_header, fw->size - readcount);
+       if (!r)
                return NULL;
-       }
 
-       return memcpy(dmc_payload, &fw->data[readcount], nbytes);
-
-error_truncated:
-       DRM_ERROR("Truncated DMC firmware, rejecting.\n");
-       return NULL;
+       return csr->dmc_payload;
 }
 
 static void intel_csr_runtime_pm_get(struct drm_i915_private *dev_priv)