This adds deferred io support if CONFIG_FB_DEFERRED_IO is enabled.
Accumulated fbdev framebuffer changes are signaled using the callback
(struct drm_framebuffer_funcs *)->dirty()
The drm_fb_helper_sys_*() functions will accumulate changes and
schedule fb_info.deferred_work _if_ fb_info.fbdefio is set.
This worker is used by the deferred io mmap code to signal that it
has been collecting page faults. The page faults and/or other changes
are then merged into a drm_clip_rect and passed to the framebuffer
dirty() function.
The driver is responsible for setting up the fb_info.fbdefio structure
and calling fb_deferred_io_init() using the provided callback:
(struct fb_info *)->fbdefio->deferred_io = drm_fb_helper_deferred_io;
Signed-off-by: Noralf Trønnes <noralf at tronnes.org>
---
drivers/gpu/drm/drm_fb_helper.c | 189 +++++++++++++++++++++++++++++++++++++++-
include/drm/drm_fb_helper.h | 15 ++++
2 files changed, 203 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 1e103c4..30f3dfd 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -48,6 +48,100 @@ MODULE_PARM_DESC(fbdev_emulation,
static LIST_HEAD(kernel_fb_helper_list);
+/*
+ * Where should I put these drm_clip_rect functions?
+ */
+
+/**
+ * drm_clip_rect_reset - Reset clip
+ * @clip: clip rectangle
+ *
+ * Sets clip to {0,0,0,0}.
+ */
+static inline void drm_clip_rect_reset(struct drm_clip_rect *clip)
+{
+ clip->x1 = 0;
+ clip->x2 = 0;
+ clip->y1 = 0;
+ clip->y2 = 0;
+}
+
+/**
+ * drm_clip_rect_is_empty - Is clip empty?
+ * @clip: clip rectangle
+ *
+ * Returns true if clip is {0,0,0,0}.
+ */
+static inline bool drm_clip_rect_is_empty(struct drm_clip_rect *clip)
+{
+ return (!clip->x1 && !clip->x2 && !clip->y1 && !clip->y2);
+}
+
+/**
+ * drm_clip_rect_sanetize - Make sure clip rectangle has sane values
+ * @clip: clip rectangle
+ * @width: maximum width of rectangle
+ * @height: maximum height of rectangle
+ *
+ * Makes sure the clip doesn't exceed the specified width and height and that
+ * x1 <= x2 and y1 <= y2.
+ */
+void drm_clip_rect_sanetize(struct drm_clip_rect *clip, u32 width, u32 height)
+{
+ if (clip->x1 > clip->x2)
+ swap(clip->x1, clip->x2);
+ if (clip->y1 > clip->y2)
+ swap(clip->y1, clip->y2);
+
+ clip->x1 = min_t(u32, clip->x1, width - 1);
+ clip->x2 = min_t(u32, clip->x2, width - 1);
+ clip->y1 = min_t(u32, clip->y1, height - 1);
+ clip->y2 = min_t(u32, clip->y2, height - 1);
+}
+EXPORT_SYMBOL(drm_clip_rect_sanetize);
+
+/**
+ * drm_clip_rect_merge - Merge clip rectangles
+ * @dst: destination clip rectangle
+ * @src: source clip rectangle(s), can be NULL
+ * @num_clips: number of source clip rectangles
+ * @width: width of rectangle if @src is NULL
+ * @height: height of rectangle if @src is NULL
+ *
+ * The dirtyfb ioctl allows for a NULL clip to be passed in,
+ * so if @src is NULL, width and height is used to set a full clip.
+ * @dst takes part in the merge unless it is empty {0,0,0,0}.
+ */
+void drm_clip_rect_merge(struct drm_clip_rect *dst,
+ struct drm_clip_rect *src, unsigned num_clips,
+ unsigned flags, u32 width, u32 height)
+{
+ int i;
+
+ if (!src || !num_clips) {
+ dst->x1 = 0;
+ dst->x2 = width - 1;
+ dst->y1 = 0;
+ dst->y2 = height - 1;
+ return;
+ }
+
+ if (drm_clip_rect_is_empty(dst)) {
+ dst->x1 = ~0;
+ dst->y1 = ~0;
+ }
+
+ for (i = 0; i < num_clips; i++) {
+ if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY)
+ i++;
+ dst->x1 = min(dst->x1, src[i].x1);
+ dst->x2 = max(dst->x2, src[i].x2);
+ dst->y1 = min(dst->y1, src[i].y1);
+ dst->y2 = max(dst->y2, src[i].y2);
+ }
+}
+EXPORT_SYMBOL(drm_clip_rect_merge);
+
/**
* DOC: fbdev helpers
*
@@ -410,6 +504,13 @@ static int restore_fbdev_mode(struct drm_fb_helper
*fb_helper)
drm_warn_on_modeset_not_all_locked(dev);
+#ifdef CONFIG_FB_DEFERRED_IO
+ spin_lock(&fb_helper->dirty_lock);
+ drm_clip_rect_merge(&fb_helper->dirty_clip, NULL, 0, 0,
+ fb_helper->fbdev->var.xres,
+ fb_helper->fbdev->var.yres);
+ spin_unlock(&fb_helper->dirty_lock);
+#endif
if (fb_helper->atomic)
return restore_fbdev_mode_atomic(fb_helper);
@@ -654,6 +755,9 @@ void drm_fb_helper_prepare(struct drm_device *dev, struct
drm_fb_helper *helper,
const struct drm_fb_helper_funcs *funcs)
{
INIT_LIST_HEAD(&helper->kernel_fb_list);
+#ifdef CONFIG_FB_DEFERRED_IO
+ spin_lock_init(&helper->dirty_lock);
+#endif
helper->funcs = funcs;
helper->dev = dev;
}
@@ -838,6 +942,76 @@ void drm_fb_helper_unlink_fbi(struct drm_fb_helper
*fb_helper)
}
EXPORT_SYMBOL(drm_fb_helper_unlink_fbi);
+#ifdef CONFIG_FB_DEFERRED_IO
+void drm_fb_helper_deferred_io(struct fb_info *info,
+ struct list_head *pagelist)
+{
+ struct drm_fb_helper *helper = info->par;
+ unsigned long start, end, min, max;
+ struct drm_clip_rect clip;
+ struct page *page;
+
+ if (!helper->fb->funcs->dirty)
+ return;
+
+ spin_lock(&helper->dirty_lock);
+ clip = helper->dirty_clip;
+ drm_clip_rect_reset(&helper->dirty_clip);
+ spin_unlock(&helper->dirty_lock);
+
+ min = ULONG_MAX;
+ max = 0;
+ list_for_each_entry(page, pagelist, lru) {
+ start = page->index << PAGE_SHIFT;
+ end = start + PAGE_SIZE - 1;
+ min = min(min, start);
+ max = max(max, end);
+ }
+
+ if (min < max) {
+ clip.x1 = 0;
+ clip.x2 = info->var.xres - 1;
+ clip.y1 = min / info->fix.line_length;
+ clip.y2 = min_t(u32, max / info->fix.line_length,
+ info->var.yres - 1);
+ } else if (drm_clip_rect_is_empty(&clip)) {
+ clip.x1 = 0;
+ clip.x2 = info->var.xres - 1;
+ clip.y1 = 0;
+ clip.y2 = info->var.yres - 1;
+ }
+
+ helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip, 1);
+}
+EXPORT_SYMBOL(drm_fb_helper_deferred_io);
+
+static void drm_fb_helper_sys_deferred(struct fb_info *info, u32 x, u32 y,
+ u32 width, u32 height)
+{
+ struct drm_fb_helper *helper = info->par;
+ struct drm_clip_rect clip;
+
+ if (!info->fbdefio)
+ return;
+
+ clip.x1 = x;
+ clip.x2 = x + width - 1;
+ clip.y1 = y;
+ clip.y2 = y + height - 1;
+
+ spin_lock(&helper->dirty_lock);
+ drm_clip_rect_merge(&helper->dirty_clip, &clip, 1, 0, 0, 0);
+ spin_unlock(&helper->dirty_lock);
+
+ schedule_delayed_work(&info->deferred_work, info->fbdefio->delay);
+}
+#else
+static inline void drm_fb_helper_sys_deferred(struct fb_info *info, u32 x, u32
y,
+ u32 width, u32 height)
+{
+}
+#endif
+
/**
* drm_fb_helper_sys_read - wrapper around fb_sys_read
* @info: fb_info struct pointer
@@ -866,7 +1040,14 @@ EXPORT_SYMBOL(drm_fb_helper_sys_read);
ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
size_t count, loff_t *ppos)
{
- return fb_sys_write(info, buf, count, ppos);
+ ssize_t ret;
+
+ ret = fb_sys_write(info, buf, count, ppos);
+ if (ret > 0)
+ drm_fb_helper_sys_deferred(info, 0, 0,
+ info->var.xres, info->var.yres);
+
+ return ret;
}
EXPORT_SYMBOL(drm_fb_helper_sys_write);
@@ -881,6 +1062,8 @@ void drm_fb_helper_sys_fillrect(struct fb_info *info,
const struct fb_fillrect *rect)
{
sys_fillrect(info, rect);
+ drm_fb_helper_sys_deferred(info, rect->dx, rect->dy,
+ rect->width, rect->height);
}
EXPORT_SYMBOL(drm_fb_helper_sys_fillrect);
@@ -895,6 +1078,8 @@ void drm_fb_helper_sys_copyarea(struct fb_info *info,
const struct fb_copyarea *area)
{
sys_copyarea(info, area);
+ drm_fb_helper_sys_deferred(info, area->dx, area->dy,
+ area->width, area->height);
}
EXPORT_SYMBOL(drm_fb_helper_sys_copyarea);
@@ -909,6 +1094,8 @@ void drm_fb_helper_sys_imageblit(struct fb_info *info,
const struct fb_image *image)
{
sys_imageblit(info, image);
+ drm_fb_helper_sys_deferred(info, image->dx, image->dy,
+ image->width, image->height);
}
EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index d8a40df..1daadc7 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -172,6 +172,9 @@ struct drm_fb_helper_connector {
* @funcs: driver callbacks for fb helper
* @fbdev: emulated fbdev device info struct
* @pseudo_palette: fake palette of 16 colors
+ * @dirty_clip: clip rectangle used with deferred_io to accumulate damage to
+ * the screen buffer
+ * @dirty_lock: spinlock protecting @dirty_clip
*
* This is the main structure used by the fbdev helpers. Drivers supporting
* fbdev emulation should embedded this into their overall driver structure.
@@ -189,6 +192,10 @@ struct drm_fb_helper {
const struct drm_fb_helper_funcs *funcs;
struct fb_info *fbdev;
u32 pseudo_palette[17];
+#ifdef CONFIG_FB_DEFERRED_IO
+ struct drm_clip_rect dirty_clip;
+ spinlock_t dirty_lock;
+#endif
/**
* @kernel_fb_list:
@@ -244,6 +251,9 @@ void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t
pitch,
void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
+void drm_fb_helper_deferred_io(struct fb_info *info,
+ struct list_head *pagelist);
+
ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
size_t count, loff_t *ppos);
ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
@@ -362,6 +372,11 @@ static inline void drm_fb_helper_unlink_fbi(struct
drm_fb_helper *fb_helper)
{
}
+static inline void drm_fb_helper_deferred_io(struct fb_info *info,
+ struct list_head *pagelist)
+{
+}
+
static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
char __user *buf, size_t count,
loff_t *ppos)
--
2.2.2
