Add YV12 pixel format support

GBM doesn't support YV12 and we need a single buffer, so request GR88 from
GBM instead and adjust the width and height. GR88 also ensures (hopefully)
that the GPU texture alignment requirements are met.

Signed-off-by: Rob Herring <robh@kernel.org>

diff --git a/gralloc_gbm.cpp b/gralloc_gbm.cpp
index a0bc34d..7e0dbda 100644 (file)
--- a/gralloc_gbm.cpp
+++ b/gralloc_gbm.cpp
@@ -83,6 +83,9 @@ static uint32_t get_gbm_format(int format)
                fmt = GBM_FORMAT_ARGB8888;
                break;
        case HAL_PIXEL_FORMAT_YV12:
+               /* YV12 is planar, but must be a single buffer so ask for GR88 */
+               fmt = GBM_FORMAT_GR88;
+               break;
        case HAL_PIXEL_FORMAT_YCbCr_422_SP:
        case HAL_PIXEL_FORMAT_YCrCb_420_SP:
        default:
@@ -131,6 +134,12 @@ static struct gralloc_gbm_bo_t *gbm_import(struct gbm_device *gbm,
        data.stride = handle->stride;
        data.format = format;
 
+       /* Adjust the width and height for a GBM GR88 buffer */
+       if (handle->format == HAL_PIXEL_FORMAT_YV12) {
+               data.width /= 2;
+               data.height += handle->height / 2;
+       }
+
        buf->bo = gbm_bo_import(gbm, GBM_BO_IMPORT_FD, &data, 0);
        if (!buf->bo) {
                delete buf;
@@ -162,6 +171,15 @@ static struct gralloc_gbm_bo_t *gbm_alloc(struct gbm_device *gbm,
                        height = 64;
        }
 
+       /*
+        * For YV12, we request GR88, so halve the width since we're getting
+        * 16bpp. Then increase the height by 1.5 for the U and V planes.
+        */
+       if (handle->format == HAL_PIXEL_FORMAT_YV12) {
+               width /= 2;
+               height += handle->height / 2;
+       }
+
        ALOGD("create BO, size=%dx%d, fmt=%d, usage=%x",
              handle->width, handle->height, handle->format, usage);
        buf->bo = gbm_bo_create(gbm, width, height, format, usage);
@@ -199,6 +217,13 @@ static int gbm_map(struct gralloc_gbm_bo_t *bo, int x, int y, int w, int h,
        if (bo->map_data)
                return -EINVAL;
 
+       if (bo->handle->format == HAL_PIXEL_FORMAT_YV12) {
+               if (x || y)
+                       ALOGE("can't map with offset for planar %p - fmt %x", bo, bo->handle->format);
+               w /= 2;
+               h += h / 2;
+       }
+
        if (enable_write)
                flags |= GBM_BO_TRANSFER_WRITE;