[PATCH v3 7/7] drm/udl: Use drm_fb_helper deferred_io support

Noralf Trønnes
2016-04-27T18:16:36Z

Use the fbdev deferred io support in drm_fb_helper.
The (struct fb_ops *)->fb_{fillrect,copyarea,imageblit} functions will
now schedule a worker instead of being flushed directly like it was
previously (recorded when in atomic).

This patch has only been compile tested.

Signed-off-by: Noralf TrÃ¸nnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---

Changes since v1:
- No need to enable deferred_io by default since drm_fb_helper uses
a dedicated worker for flushing

drivers/gpu/drm/udl/udl_drv.h | 2 -
drivers/gpu/drm/udl/udl_fb.c | 140 ++----------------------------------------
2 files changed, 6 insertions(+), 136 deletions(-)

diff --git a/drivers/gpu/drm/udl/udl_drv.h b/drivers/gpu/drm/udl/udl_drv.h
index 4a064ef..0b03d34 100644
--- a/drivers/gpu/drm/udl/udl_drv.h
+++ b/drivers/gpu/drm/udl/udl_drv.h
@@ -81,8 +81,6 @@ struct udl_framebuffer {
struct drm_framebuffer base;
struct udl_gem_object *obj;
bool active_16; /* active on the 16-bit channel */
- int x1, y1, x2, y2; /* dirty rect */
- spinlock_t dirty_lock;
};

#define to_udl_fb(x) container_of(x, struct udl_framebuffer, base)
diff --git a/drivers/gpu/drm/udl/udl_fb.c b/drivers/gpu/drm/udl/udl_fb.c
index a52de2f..4a9b432 100644
--- a/drivers/gpu/drm/udl/udl_fb.c
+++ b/drivers/gpu/drm/udl/udl_fb.c
@@ -77,68 +77,6 @@ static uint16_t rgb16(uint32_t col)
}
#endif

-/*
- * NOTE: fb_defio.c is holding info->fbdefio.mutex
- * Touching ANY framebuffer memory that triggers a page fault
- * in fb_defio will cause a deadlock, when it also tries to
- * grab the same mutex.
- */
-static void udlfb_dpy_deferred_io(struct fb_info *info,
- struct list_head *pagelist)
-{
- struct page *cur;
- struct fb_deferred_io *fbdefio = info->fbdefio;
- struct udl_fbdev *ufbdev = info->par;
- struct drm_device *dev = ufbdev->ufb.base.dev;
- struct udl_device *udl = dev->dev_private;
- struct urb *urb;
- char *cmd;
- cycles_t start_cycles, end_cycles;
- int bytes_sent = 0;
- int bytes_identical = 0;
- int bytes_rendered = 0;
-
- if (!fb_defio)
- return;
-
- start_cycles = get_cycles();
-
- urb = udl_get_urb(dev);
- if (!urb)
- return;
-
- cmd = urb->transfer_buffer;
-
- /* walk the written page list and render each to device */
- list_for_each_entry(cur, &fbdefio->pagelist, lru) {
-
- if (udl_render_hline(dev, (ufbdev->ufb.base.bits_per_pixel / 8),
- &urb, (char *) info->fix.smem_start,
- &cmd, cur->index << PAGE_SHIFT,
- cur->index << PAGE_SHIFT,
- PAGE_SIZE, &bytes_identical, &bytes_sent))
- goto error;
- bytes_rendered += PAGE_SIZE;
- }
-
- if (cmd > (char *) urb->transfer_buffer) {
- /* Send partial buffer remaining before exiting */
- int len = cmd - (char *) urb->transfer_buffer;
- udl_submit_urb(dev, urb, len);
- bytes_sent += len;
- } else
- udl_urb_completion(urb);
-
-error:
- atomic_add(bytes_sent, &udl->bytes_sent);
- atomic_add(bytes_identical, &udl->bytes_identical);
- atomic_add(bytes_rendered, &udl->bytes_rendered);
- end_cycles = get_cycles();
- atomic_add(((unsigned int) ((end_cycles - start_cycles)
- >> 10)), /* Kcycles */
- &udl->cpu_kcycles_used);
-}
-
int udl_handle_damage(struct udl_framebuffer *fb, int x, int y,
int width, int height)
{
@@ -152,9 +90,6 @@ int udl_handle_damage(struct udl_framebuffer *fb, int x, int y,
struct urb *urb;
int aligned_x;
int bpp = (fb->base.bits_per_pixel / 8);
- int x2, y2;
- bool store_for_later = false;
- unsigned long flags;

if (!fb->active_16)
return 0;
@@ -180,38 +115,6 @@ int udl_handle_damage(struct udl_framebuffer *fb, int x, int y,
(y + height > fb->base.height))
return -EINVAL;

- /* if we are in atomic just store the info
- can't test inside spin lock */
- if (in_atomic())
- store_for_later = true;
-
- x2 = x + width - 1;
- y2 = y + height - 1;
-
- spin_lock_irqsave(&fb->dirty_lock, flags);
-
- if (fb->y1 < y)
- y = fb->y1;
- if (fb->y2 > y2)
- y2 = fb->y2;
- if (fb->x1 < x)
- x = fb->x1;
- if (fb->x2 > x2)
- x2 = fb->x2;
-
- if (store_for_later) {
- fb->x1 = x;
- fb->x2 = x2;
- fb->y1 = y;
- fb->y2 = y2;
- spin_unlock_irqrestore(&fb->dirty_lock, flags);
- return 0;
- }
-
- fb->x1 = fb->y1 = INT_MAX;
- fb->x2 = fb->y2 = 0;
-
- spin_unlock_irqrestore(&fb->dirty_lock, flags);
start_cycles = get_cycles();

urb = udl_get_urb(dev);
@@ -219,14 +122,14 @@ int udl_handle_damage(struct udl_framebuffer *fb, int x, int y,
return 0;
cmd = urb->transfer_buffer;

- for (i = y; i <= y2 ; i++) {
+ for (i = y; i < height ; i++) {
const int line_offset = fb->base.pitches[0] * i;
const int byte_offset = line_offset + (x * bpp);
const int dev_byte_offset = (fb->base.width * bpp * i) + (x * bpp);
if (udl_render_hline(dev, bpp, &urb,
(char *) fb->obj->vmapping,
&cmd, byte_offset, dev_byte_offset,
- (x2 - x + 1) * bpp,
+ width * bpp,
&bytes_identical, &bytes_sent))
goto error;
}
@@ -283,36 +186,6 @@ static int udl_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
return 0;
}

-static void udl_fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
-{
- struct udl_fbdev *ufbdev = info->par;
-
- sys_fillrect(info, rect);
-
- udl_handle_damage(&ufbdev->ufb, rect->dx, rect->dy, rect->width,
- rect->height);
-}
-
-static void udl_fb_copyarea(struct fb_info *info, const struct fb_copyarea *region)
-{
- struct udl_fbdev *ufbdev = info->par;
-
- sys_copyarea(info, region);
-
- udl_handle_damage(&ufbdev->ufb, region->dx, region->dy, region->width,
- region->height);
-}
-
-static void udl_fb_imageblit(struct fb_info *info, const struct fb_image *image)
-{
- struct udl_fbdev *ufbdev = info->par;
-
- sys_imageblit(info, image);
-
- udl_handle_damage(&ufbdev->ufb, image->dx, image->dy, image->width,
- image->height);
-}
-
/*
* It's common for several clients to have framebuffer open simultaneously.
* e.g. both fbcon and X. Makes things interesting.
@@ -339,7 +212,7 @@ static int udl_fb_open(struct fb_info *info, int user)

if (fbdefio) {
fbdefio->delay = DL_DEFIO_WRITE_DELAY;
- fbdefio->deferred_io = udlfb_dpy_deferred_io;
+ fbdefio->deferred_io = drm_fb_helper_deferred_io;
}

info->fbdefio = fbdefio;
@@ -379,9 +252,9 @@ static struct fb_ops udlfb_ops = {
.owner = THIS_MODULE,
.fb_check_var = drm_fb_helper_check_var,
.fb_set_par = drm_fb_helper_set_par,
- .fb_fillrect = udl_fb_fillrect,
- .fb_copyarea = udl_fb_copyarea,
- .fb_imageblit = udl_fb_imageblit,
+ .fb_fillrect = drm_fb_helper_sys_fillrect,
+ .fb_copyarea = drm_fb_helper_sys_copyarea,
+ .fb_imageblit = drm_fb_helper_sys_imageblit,
.fb_pan_display = drm_fb_helper_pan_display,
.fb_blank = drm_fb_helper_blank,
.fb_setcmap = drm_fb_helper_setcmap,
@@ -458,7 +331,6 @@ udl_framebuffer_init(struct drm_device *dev,
{
int ret;

- spin_lock_init(&ufb->dirty_lock);
ufb->obj = obj;
drm_helper_mode_fill_fb_struct(&ufb->base, mode_cmd);
ret = drm_framebuffer_init(dev, &ufb->base, &udlfb_funcs);
--
2.2.2