drm/i915/bios: have functions return vbt, not bdb, header pointer

This will simplify further work.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/d2c5210402fdd8c277e1d50892b0620d10c50ae8.1450089383.git.jani.nikula@intel.com

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 401e114..2fc2a99 100644 (file)
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -1214,7 +1214,14 @@ init_vbt_defaults(struct drm_i915_private *dev_priv)
        }
 }
 
-static const struct bdb_header *validate_vbt(const void *base,
+static const struct bdb_header *get_bdb_header(const struct vbt_header *vbt)
+{
+       const void *_vbt = vbt;
+
+       return _vbt + vbt->bdb_offset;
+}
+
+static const struct vbt_header *validate_vbt(const void *base,
                                             size_t size,
                                             const void *_vbt,
                                             const char *source)
@@ -1223,6 +1230,9 @@ static const struct bdb_header *validate_vbt(const void *base,
        const struct vbt_header *vbt = _vbt;
        const struct bdb_header *bdb;
 
+       if (!vbt)
+               return NULL;
+
        if (offset + sizeof(struct vbt_header) > size) {
                DRM_DEBUG_DRIVER("VBT header incomplete\n");
                return NULL;
@@ -1239,7 +1249,7 @@ static const struct bdb_header *validate_vbt(const void *base,
                return NULL;
        }
 
-       bdb = base + offset;
+       bdb = get_bdb_header(vbt);
        if (offset + bdb->bdb_size > size) {
                DRM_DEBUG_DRIVER("BDB incomplete\n");
                return NULL;
@@ -1247,12 +1257,12 @@ static const struct bdb_header *validate_vbt(const void *base,
 
        DRM_DEBUG_KMS("Using VBT from %s: %20s\n",
                      source, vbt->signature);
-       return bdb;
+       return vbt;
 }
 
-static const struct bdb_header *find_vbt(void __iomem *bios, size_t size)
+static const struct vbt_header *find_vbt(void __iomem *bios, size_t size)
 {
-       const struct bdb_header *bdb = NULL;
+       const struct vbt_header *vbt = NULL;
        size_t i;
 
        /* Scour memory looking for the VBT signature. */
@@ -1266,12 +1276,12 @@ static const struct bdb_header *find_vbt(void __iomem *bios, size_t size)
                         */
                        void *_bios = (void __force *) bios;
 
-                       bdb = validate_vbt(_bios, size, _bios + i, "PCI ROM");
+                       vbt = validate_vbt(_bios, size, _bios + i, "PCI ROM");
                        break;
                }
        }
 
-       return bdb;
+       return vbt;
 }
 
 /**
@@ -1288,7 +1298,8 @@ intel_parse_bios(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct pci_dev *pdev = dev->pdev;
-       const struct bdb_header *bdb = NULL;
+       const struct vbt_header *vbt;
+       const struct bdb_header *bdb;
        u8 __iomem *bios = NULL;
 
        if (HAS_PCH_NOP(dev))
@@ -1297,24 +1308,24 @@ intel_parse_bios(struct drm_device *dev)
        init_vbt_defaults(dev_priv);
 
        /* XXX Should this validation be moved to intel_opregion.c? */
-       if (dev_priv->opregion.vbt)
-               bdb = validate_vbt(dev_priv->opregion.header, OPREGION_SIZE,
-                                  dev_priv->opregion.vbt, "OpRegion");
-
-       if (bdb == NULL) {
+       vbt = validate_vbt(dev_priv->opregion.header, OPREGION_SIZE,
+                          dev_priv->opregion.vbt, "OpRegion");
+       if (!vbt) {
                size_t size;
 
                bios = pci_map_rom(pdev, &size);
                if (!bios)
                        return -1;
 
-               bdb = find_vbt(bios, size);
-               if (!bdb) {
+               vbt = find_vbt(bios, size);
+               if (!vbt) {
                        pci_unmap_rom(pdev, bios);
                        return -1;
                }
        }
 
+       bdb = get_bdb_header(vbt);
+
        /* Grab useful general definitions */
        parse_general_features(dev_priv, bdb);
        parse_general_definitions(dev_priv, bdb);