drm/core: Add drm_afbc_framebuffer and a corresponding helper

The new struct contains afbc-specific data.

The new function can be used by drivers which support afbc to complete
the preparation of struct drm_afbc_framebuffer. It must be called after
allocating the said struct and calling drm_gem_fb_init_with_funcs().

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: James Qian Wang <james.qian.wang@arm.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311145541.29186-3-andrzej.p@collabora.com

diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst
index 439656f..37a3a02 100644 (file)
--- a/Documentation/gpu/todo.rst
+++ b/Documentation/gpu/todo.rst
@@ -404,6 +404,21 @@ Contact: Laurent Pinchart, respective driver maintainers
 
 Level: Intermediate
 
+Encode cpp properly in malidp
+-----------------------------
+
+cpp (chars per pixel) is not encoded properly in malidp, zero is
+used instead. afbc implementation needs bpp or cpp, but if it is
+zero it needs to be provided elsewhere, and so the bpp field exists
+in struct drm_afbc_framebuffer.
+
+Properly encode cpp in malidp and remove the bpp field in struct
+drm_afbc_framebuffer.
+
+Contact: malidp maintainers
+
+Level: Intermediate
+
 Core refactorings
 =================
 

diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index 86c1907..7e3982c 100644 (file)
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -21,6 +21,13 @@
 #include <drm/drm_modeset_helper.h>
 #include <drm/drm_simple_kms_helper.h>
 
+#define AFBC_HEADER_SIZE               16
+#define AFBC_TH_LAYOUT_ALIGNMENT       8
+#define AFBC_HDR_ALIGN                 64
+#define AFBC_SUPERBLOCK_PIXELS         256
+#define AFBC_SUPERBLOCK_ALIGNMENT      128
+#define AFBC_TH_BODY_START_ALIGNMENT   4096
+
 /**
  * DOC: overview
  *
@@ -302,6 +309,107 @@ drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file,
 }
 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty);
 
+static int drm_gem_afbc_min_size(struct drm_device *dev,
+                                const struct drm_mode_fb_cmd2 *mode_cmd,
+                                struct drm_afbc_framebuffer *afbc_fb)
+{
+       const struct drm_format_info *info;
+       __u32 n_blocks, w_alignment, h_alignment, hdr_alignment;
+       /* remove bpp when all users properly encode cpp in drm_format_info */
+       __u32 bpp;
+
+       switch (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK) {
+       case AFBC_FORMAT_MOD_BLOCK_SIZE_16x16:
+               afbc_fb->block_width = 16;
+               afbc_fb->block_height = 16;
+               break;
+       case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8:
+               afbc_fb->block_width = 32;
+               afbc_fb->block_height = 8;
+               break;
+       /* no user exists yet - fall through */
+       case AFBC_FORMAT_MOD_BLOCK_SIZE_64x4:
+       case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4:
+       default:
+               DRM_DEBUG_KMS("Invalid AFBC_FORMAT_MOD_BLOCK_SIZE: %lld.\n",
+                             mode_cmd->modifier[0]
+                             & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK);
+               return -EINVAL;
+       }
+
+       /* tiled header afbc */
+       w_alignment = afbc_fb->block_width;
+       h_alignment = afbc_fb->block_height;
+       hdr_alignment = AFBC_HDR_ALIGN;
+       if (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_TILED) {
+               w_alignment *= AFBC_TH_LAYOUT_ALIGNMENT;
+               h_alignment *= AFBC_TH_LAYOUT_ALIGNMENT;
+               hdr_alignment = AFBC_TH_BODY_START_ALIGNMENT;
+       }
+
+       afbc_fb->aligned_width = ALIGN(mode_cmd->width, w_alignment);
+       afbc_fb->aligned_height = ALIGN(mode_cmd->height, h_alignment);
+       afbc_fb->offset = mode_cmd->offsets[0];
+
+       info = drm_get_format_info(dev, mode_cmd);
+       /*
+        * Change to always using info->cpp[0]
+        * when all users properly encode it
+        */
+       bpp = info->cpp[0] ? info->cpp[0] * 8 : afbc_fb->bpp;
+
+       n_blocks = (afbc_fb->aligned_width * afbc_fb->aligned_height)
+                  / AFBC_SUPERBLOCK_PIXELS;
+       afbc_fb->afbc_size = ALIGN(n_blocks * AFBC_HEADER_SIZE, hdr_alignment);
+       afbc_fb->afbc_size += n_blocks * ALIGN(bpp * AFBC_SUPERBLOCK_PIXELS / 8,
+                                              AFBC_SUPERBLOCK_ALIGNMENT);
+
+       return 0;
+}
+
+/**
+ * drm_gem_fb_afbc_init() - Helper function for drivers using afbc to
+ *                         fill and validate all the afbc-specific
+ *                         struct drm_afbc_framebuffer members
+ *
+ * @dev: DRM device
+ * @afbc_fb: afbc-specific framebuffer
+ * @mode_cmd: Metadata from the userspace framebuffer creation request
+ * @afbc_fb: afbc framebuffer
+ *
+ * This function can be used by drivers which support afbc to complete
+ * the preparation of struct drm_afbc_framebuffer. It must be called after
+ * allocating the said struct and calling drm_gem_fb_init_with_funcs().
+ * It is caller's responsibility to put afbc_fb->base.obj objects in case
+ * the call is unsuccessful.
+ *
+ * Returns:
+ * Zero on success or a negative error value on failure.
+ */
+int drm_gem_fb_afbc_init(struct drm_device *dev,
+                        const struct drm_mode_fb_cmd2 *mode_cmd,
+                        struct drm_afbc_framebuffer *afbc_fb)
+{
+       const struct drm_format_info *info;
+       struct drm_gem_object **objs;
+       int ret;
+
+       objs = afbc_fb->base.obj;
+       info = drm_get_format_info(dev, mode_cmd);
+       if (!info)
+               return -EINVAL;
+
+       ret = drm_gem_afbc_min_size(dev, mode_cmd, afbc_fb);
+       if (ret < 0)
+               return ret;
+
+       if (objs[0]->size < afbc_fb->afbc_size)
+               return -EINVAL;
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init);
+
 /**
  * drm_gem_fb_prepare_fb() - Prepare a GEM backed framebuffer
  * @plane: Plane

diff --git a/include/drm/drm_framebuffer.h b/include/drm/drm_framebuffer.h
index c0e0256..e9f1b0e 100644 (file)
--- a/include/drm/drm_framebuffer.h
+++ b/include/drm/drm_framebuffer.h
@@ -297,4 +297,49 @@ int drm_framebuffer_plane_width(int width,
 int drm_framebuffer_plane_height(int height,
                                 const struct drm_framebuffer *fb, int plane);
 
+/**
+ * struct drm_afbc_framebuffer - a special afbc frame buffer object
+ *
+ * A derived class of struct drm_framebuffer, dedicated for afbc use cases.
+ */
+struct drm_afbc_framebuffer {
+       /**
+        * @base: base framebuffer structure.
+        */
+       struct drm_framebuffer base;
+       /**
+        * @block_widht: width of a single afbc block
+        */
+       u32 block_width;
+       /**
+        * @block_widht: height of a single afbc block
+        */
+       u32 block_height;
+       /**
+        * @aligned_width: aligned frame buffer width
+        */
+       u32 aligned_width;
+       /**
+        * @aligned_height: aligned frame buffer height
+        */
+       u32 aligned_height;
+       /**
+        * @offset: offset of the first afbc header
+        */
+       u32 offset;
+       /**
+        * @afbc_size: minimum size of afbc buffer
+        */
+       u32 afbc_size;
+       /**
+        * @bpp: bpp value for this afbc buffer
+        * To be removed when users such as malidp
+        * properly store the cpp in drm_format_info.
+        * New users should not start using this field.
+        */
+       u32 bpp;
+};
+
+#define fb_to_afbc_fb(x) container_of(x, struct drm_afbc_framebuffer, base)
+
 #endif

diff --git a/include/drm/drm_gem_framebuffer_helper.h b/include/drm/drm_gem_framebuffer_helper.h
index c029c16..6b01315 100644 (file)
--- a/include/drm/drm_gem_framebuffer_helper.h
+++ b/include/drm/drm_gem_framebuffer_helper.h
@@ -1,6 +1,7 @@
 #ifndef __DRM_GEM_FB_HELPER_H__
 #define __DRM_GEM_FB_HELPER_H__
 
+struct drm_afbc_framebuffer;
 struct drm_device;
 struct drm_fb_helper_surface_size;
 struct drm_file;
@@ -12,6 +13,8 @@ struct drm_plane;
 struct drm_plane_state;
 struct drm_simple_display_pipe;
 
+#define AFBC_VENDOR_AND_TYPE_MASK      GENMASK_ULL(63, 52)
+
 struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb,
                                          unsigned int plane);
 void drm_gem_fb_destroy(struct drm_framebuffer *fb);
@@ -34,6 +37,13 @@ struct drm_framebuffer *
 drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file,
                             const struct drm_mode_fb_cmd2 *mode_cmd);
 
+#define drm_is_afbc(modifier) \
+       (((modifier) & AFBC_VENDOR_AND_TYPE_MASK) == DRM_FORMAT_MOD_ARM_AFBC(0))
+
+int drm_gem_fb_afbc_init(struct drm_device *dev,
+                        const struct drm_mode_fb_cmd2 *mode_cmd,
+                        struct drm_afbc_framebuffer *afbc_fb);
+
 int drm_gem_fb_prepare_fb(struct drm_plane *plane,
                          struct drm_plane_state *state);
 int drm_gem_fb_simple_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,