1 files changed, 47 insertions, 2 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_bios.c b/drivers/gpu/drm/radeon/radeon_bios.c
index 96e37a6e7ce4..34a9b9119518 100644
--- a/drivers/gpu/drm/radeon/radeon_bios.c
+++ b/drivers/gpu/drm/radeon/radeon_bios.c
@@ -33,12 +33,50 @@
 /*
  * BIOS.
  */
+
+/* If you boot an IGP board with a discrete card as the primary,
+ * the IGP rom is not accessible via the rom bar as the IGP rom is
+ * part of the system bios.  On boot, the system bios puts a
+ * copy of the igp rom at the start of vram if a discrete card is
+ * present.
+ */
+static bool igp_read_bios_from_vram(struct radeon_device *rdev)
+{
+        uint8_t __iomem *bios;
+        resource_size_t vram_base;
+        resource_size_t size = 256 * 1024; /* ??? */
+
+        rdev->bios = NULL;
+        vram_base = drm_get_resource_start(rdev->ddev, 0);
+        bios = ioremap(vram_base, size);
+        if (!bios) {
+                DRM_ERROR("Unable to mmap vram\n");
+                return false;
+        }
+
+        if (size == 0 || bios[0] != 0x55 || bios[1] != 0xaa) {
+                iounmap(bios);
+                DRM_ERROR("bad rom signature\n");
+                return false;
+        }
+        rdev->bios = kmalloc(size, GFP_KERNEL);
+        if (rdev->bios == NULL) {
+                iounmap(bios);
+                DRM_ERROR("kmalloc failed\n");
+                return false;
+        }
+        memcpy(rdev->bios, bios, size);
+        iounmap(bios);
+        return true;
+}
+
 static bool radeon_read_bios(struct radeon_device *rdev)
 {
         uint8_t __iomem *bios;
         size_t size;
 
         rdev->bios = NULL;
+        /* XXX: some cards may return 0 for rom size? ddx has a workaround */
         bios = pci_map_rom(rdev->pdev, &size);
         if (!bios) {
                 return false;
@@ -341,7 +379,9 @@ static bool legacy_read_disabled_bios(struct radeon_device *rdev)
 
 static bool radeon_read_disabled_bios(struct radeon_device *rdev)
 {
-        if (rdev->family >= CHIP_RV770)
+        if (rdev->flags & RADEON_IS_IGP)
+                return igp_read_bios_from_vram(rdev);
+        else if (rdev->family >= CHIP_RV770)
                 return r700_read_disabled_bios(rdev);
         else if (rdev->family >= CHIP_R600)
                 return r600_read_disabled_bios(rdev);
@@ -356,7 +396,12 @@ bool radeon_get_bios(struct radeon_device *rdev)
         bool r;
         uint16_t tmp;
 
-        r = radeon_read_bios(rdev);
+        if (rdev->flags & RADEON_IS_IGP) {
+                r = igp_read_bios_from_vram(rdev);
+                if (r == false)
+                        r = radeon_read_bios(rdev);
+        } else
+                r = radeon_read_bios(rdev);
         if (r == false) {
                 r = radeon_read_disabled_bios(rdev);
         }