[PATCH v2 4/5] drm/ofdrm: Store xfrm buffer in device instance

[Thomas Zimmermann]

Store and instance of struct drm_xfrm_buf in struct ofdrm_device and
keep the allocated memory allocated across display updates. Avoid
possibly reallocating temporary memory on each display update. Instead
preallocate temporary memory during initialization. Releasing the DRM
device also releases the xfrm buffer.

v2:
        * reserve storage during probe

Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
---
 drivers/gpu/drm/tiny/ofdrm.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/tiny/ofdrm.c b/drivers/gpu/drm/tiny/ofdrm.c
index 1add55c872670..ede7b168bd9d0 100644
--- a/drivers/gpu/drm/tiny/ofdrm.c
+++ b/drivers/gpu/drm/tiny/ofdrm.c
@@ -301,6 +301,7 @@ struct ofdrm_device {
        struct drm_display_mode mode;
        const struct drm_format_info *format;
        unsigned int pitch;
+       struct drm_xfrm_buf xfrm;
 
        /* colormap */
        void __iomem *cmap_base;
@@ -796,7 +797,6 @@ static void ofdrm_primary_plane_helper_atomic_update(struct 
drm_plane *plane,
        struct drm_framebuffer *fb = plane_state->fb;
        unsigned int dst_pitch = odev->pitch;
        const struct drm_format_info *dst_format = odev->format;
-       struct drm_xfrm_buf xfrm = DRM_XFRM_BUF_INIT;
        struct drm_atomic_helper_damage_iter iter;
        struct drm_rect damage;
        int ret, idx;
@@ -818,13 +818,12 @@ static void 
ofdrm_primary_plane_helper_atomic_update(struct drm_plane *plane,
 
                iosys_map_incr(&dst, drm_fb_clip_offset(dst_pitch, dst_format, 
&dst_clip));
                drm_fb_blit(&dst, &dst_pitch, dst_format->format, 
shadow_plane_state->data, fb,
-                           &damage, &xfrm);
+                           &damage, &odev->xfrm);
        }
 
        drm_dev_exit(idx);
 out_drm_gem_fb_end_cpu_access:
        drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
-       drm_xfrm_buf_release(&xfrm);
 }
 
 static void ofdrm_primary_plane_helper_atomic_disable(struct drm_plane *plane,
@@ -1096,6 +1095,7 @@ static struct ofdrm_device *ofdrm_device_create(struct 
drm_driver *drv,
        struct drm_connector *connector;
        unsigned long max_width, max_height;
        size_t nformats;
+       void *buf;
        int ret;
 
        odev = devm_drm_dev_alloc(&pdev->dev, drv, struct ofdrm_device, dev);
@@ -1248,6 +1248,13 @@ static struct ofdrm_device *ofdrm_device_create(struct 
drm_driver *drv,
        drm_dbg(dev, "framebuffer format=%p4cc, size=%dx%d, linebytes=%d 
byte\n",
                &format->format, width, height, linebytes);
 
+       ret = drmm_xfrm_buf_init(dev, &odev->xfrm);
+       if (ret)
+               return ERR_PTR(ret);
+       buf = drm_xfrm_buf_reserve(&odev->xfrm, odev->pitch, GFP_KERNEL);
+       if (!buf)
+               return ERR_PTR(-ENOMEM);
+
        /*
         * Mode-setting pipeline
         */
-- 
2.42.0