drm/radeon/kms/atom: fix handling of FB scratch indices

[pandora-kernel.git] / drivers / gpu / drm / radeon / atom.c

diff --git a/drivers/gpu/drm/radeon/atom.c b/drivers/gpu/drm/radeon/atom.c
index e88c644..14cc88a 100644 (file)
--- a/drivers/gpu/drm/radeon/atom.c
+++ b/drivers/gpu/drm/radeon/atom.c
@@ -277,7 +277,12 @@ static uint32_t atom_get_src_int(atom_exec_context *ctx, uint8_t attr,
        case ATOM_ARG_FB:
                idx = U8(*ptr);
                (*ptr)++;
-               val = gctx->scratch[((gctx->fb_base + idx) / 4)];
+               if ((gctx->fb_base + (idx * 4)) > gctx->scratch_size_bytes) {
+                       DRM_ERROR("ATOM: fb read beyond scratch region: %d vs. %d\n",
+                                 gctx->fb_base + (idx * 4), gctx->scratch_size_bytes);
+                       val = 0;
+               } else
+                       val = gctx->scratch[(gctx->fb_base / 4) + idx];
                if (print)
                        DEBUG("FB[0x%02X]", idx);
                break;
@@ -531,7 +536,11 @@ static void atom_put_dst(atom_exec_context *ctx, int arg, uint8_t attr,
        case ATOM_ARG_FB:
                idx = U8(*ptr);
                (*ptr)++;
-               gctx->scratch[((gctx->fb_base + idx) / 4)] = val;
+               if ((gctx->fb_base + (idx * 4)) > gctx->scratch_size_bytes) {
+                       DRM_ERROR("ATOM: fb write beyond scratch region: %d vs. %d\n",
+                                 gctx->fb_base + (idx * 4), gctx->scratch_size_bytes);
+               } else
+                       gctx->scratch[(gctx->fb_base / 4) + idx] = val;
                DEBUG("FB[0x%02X]", idx);
                break;
        case ATOM_ARG_PLL:
@@ -1370,11 +1379,13 @@ int atom_allocate_fb_scratch(struct atom_context *ctx)
 
                usage_bytes = firmware_usage->asFirmwareVramReserveInfo[0].usFirmwareUseInKb * 1024;
        }
+       ctx->scratch_size_bytes = 0;
        if (usage_bytes == 0)
                usage_bytes = 20 * 1024;
        /* allocate some scratch memory */
        ctx->scratch = kzalloc(usage_bytes, GFP_KERNEL);
        if (!ctx->scratch)
                return -ENOMEM;
+       ctx->scratch_size_bytes = usage_bytes;
        return 0;
 }