drm_hwcomposer: Add Imagination platform support

External Android.bp file should be created in order to build this module:
```
cc_library_shared {
    name: "hwcomposer.drm_imagination",
    defaults: ["hwcomposer.drm_defaults"],
    srcs: [":drm_hwcomposer_platformimagination"],
    whole_static_libs: ["drm_hwcomposer"],
    shared_libs: ["libion"],
    include_dirs: [
        "path/to/imgtec/include/files",
    ],
}
```
libion is needed to make ion.h header visible `linux/ion.h`.

Signed-off-by: Roman Stratiienko <roman.stratiienko@globallogic.com>

3 files changed, 112 insertions, 0 deletions

diff --git a/Android.bp b/Android.bp
index 5681cb7..85be0b5 100644
--- a/Android.bp
+++ b/Android.bp
@@ -110,6 +110,15 @@ cc_library_shared {
     include_dirs: ["external/minigbm/cros_gralloc"],
 }
 
+// Used by hwcomposer.drm_imagination
+filegroup {
+    name: "drm_hwcomposer_platformimagination",
+    srcs: [
+        "platform/platformdrmgeneric.cpp",
+        "platform/platformimagination.cpp",
+    ],
+}
+
 // Used by hwcomposer.drm_hikey and hwcomposer.drm_hikey960
 filegroup {
     name: "drm_hwcomposer_platformhisi",
diff --git a/platform/platformimagination.cpp b/platform/platformimagination.cpp
new file mode 100644
index 0000000..b94ca0b
--- /dev/null
+++ b/platform/platformimagination.cpp
@@ -0,0 +1,81 @@
+#define LOG_TAG "hwc-platform-imagination"
+
+#include "platformimagination.h"
+#include <drm/drm_fourcc.h>
+#include <log/log.h>
+#include <xf86drm.h>
+
+#include "img_gralloc1_public.h"
+
+namespace android {
+
+Importer *Importer::CreateInstance(DrmDevice *drm) {
+  ImaginationImporter *importer = new ImaginationImporter(drm);
+  if (!importer)
+    return NULL;
+
+  int ret = importer->Init();
+  if (ret) {
+    ALOGE("Failed to initialize the Imagination importer %d", ret);
+    delete importer;
+    return NULL;
+  }
+  return importer;
+}
+
+int ImaginationImporter::ImportBuffer(buffer_handle_t handle,
+                                      hwc_drm_bo_t *bo) {
+  IMG_native_handle_t *hnd = (IMG_native_handle_t *)handle;
+  if (!hnd)
+    return -EINVAL;
+
+  uint32_t gem_handle;
+  int ret = drmPrimeFDToHandle(drm_->fd(), hnd->fd[0], &gem_handle);
+  if (ret) {
+    ALOGE("failed to import prime fd %d ret=%d", hnd->fd[0], ret);
+    return ret;
+  }
+
+  /* Extra bits are responsible for buffer compression and memory layout */
+  if (hnd->iFormat & ~0x10f) {
+    ALOGE("Special buffer formats are not supported");
+    return -EINVAL;
+  }
+
+  memset(bo, 0, sizeof(hwc_drm_bo_t));
+  bo->width = hnd->iWidth;
+  bo->height = hnd->iHeight;
+  bo->usage = hnd->usage;
+  bo->gem_handles[0] = gem_handle;
+  bo->pitches[0] = ALIGN(hnd->iWidth, HW_ALIGN) * hnd->uiBpp >> 3;
+
+  switch (hnd->iFormat) {
+#ifdef HAL_PIXEL_FORMAT_BGRX_8888
+    case HAL_PIXEL_FORMAT_BGRX_8888:
+      bo->format = DRM_FORMAT_XRGB8888;
+      break;
+#endif
+    default:
+      bo->format = ConvertHalFormatToDrm(hnd->iFormat & 0xf);
+      if (bo->format == DRM_FORMAT_INVALID) {
+        ALOGE("Cannot convert hal format to drm format %u", hnd->iFormat);
+        return -EINVAL;
+      }
+  }
+
+  ret = drmModeAddFB2(drm_->fd(), bo->width, bo->height, bo->format,
+                      bo->gem_handles, bo->pitches, bo->offsets, &bo->fb_id, 0);
+  if (ret) {
+    ALOGE("could not create drm fb ret: %d", ret);
+    return ret;
+  }
+
+  return 0;
+}
+
+std::unique_ptr<Planner> Planner::CreateInstance(DrmDevice *) {
+  std::unique_ptr<Planner> planner(new Planner);
+  planner->AddStage<PlanStageGreedy>();
+  return planner;
+}
+}  // namespace android
diff --git a/platform/platformimagination.h b/platform/platformimagination.h
new file mode 100644
index 0000000..85dfc45
--- /dev/null
+++ b/platform/platformimagination.h
@@ -0,0 +1,22 @@
+#ifndef PLATFORMIMAGINATION_H
+#define PLATFORMIMAGINATION_H
+
+#include "drmdevice.h"
+#include "platform.h"
+#include "platformdrmgeneric.h"
+
+#include <stdatomic.h>
+
+#include <hardware/gralloc.h>
+
+namespace android {
+
+class ImaginationImporter : public DrmGenericImporter {
+ public:
+  using DrmGenericImporter::DrmGenericImporter;
+
+  int ImportBuffer(buffer_handle_t handle, hwc_drm_bo_t *bo) override;
+};
+}  // namespace android
+
+#endif  // PLATFORMIMAGINATION_H