On 01/05/2021 23:00, Sebastian Reichel wrote:
Running a legacy application, which directly uses /dev/fb0
currently results in display not being refreshed when the
application mmaps the memory instead of calling write().
Deferred IO support will also schedule dirty_work with the
damage collected from the mmap page writes and thus gets
some more legacy applications working.
Delay frequency settings have been taken over from
drm_fb_helper_generic_probe().
Reported-by: Carl Philipp Klemm <philipp@xxxxxxxx>
Tested-by: Carl Philipp Klemm <philipp@xxxxxxxx>
Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
---
Hi,
I still need to fix my Droid 4, so I only compile tested this
myself.
-- Sebastian
---
drivers/gpu/drm/omapdrm/omap_fbdev.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/gpu/drm/omapdrm/omap_fbdev.c b/drivers/gpu/drm/omapdrm/omap_fbdev.c
index 42eac6ad12bd..fc3897d2d7cc 100644
--- a/drivers/gpu/drm/omapdrm/omap_fbdev.c
+++ b/drivers/gpu/drm/omapdrm/omap_fbdev.c
@@ -87,6 +87,11 @@ static const struct fb_ops omap_fb_ops = {
.fb_imageblit = drm_fb_helper_sys_imageblit,
};
+static struct fb_deferred_io omap_fb_defio = {
+ .delay = HZ / 20,
+ .deferred_io = drm_fb_helper_deferred_io,
+};
+
static int omap_fbdev_create(struct drm_fb_helper *helper,
struct drm_fb_helper_surface_size *sizes)
{
@@ -176,6 +181,9 @@ static int omap_fbdev_create(struct drm_fb_helper *helper,
drm_fb_helper_fill_info(fbi, helper, sizes);
+ fbi->fbdefio = &omap_fb_defio;
+ fb_deferred_io_init(fbi);
+
dev->mode_config.fb_base = dma_addr;
fbi->screen_buffer = omap_gem_vaddr(fbdev->bo);
base-commit: 152d32aa846835987966fd20ee1143b0e05036a0
On DRA76 EVM, with parallel output, this causes cache-flush problem.
When I run my simple fbtest, which just draws to the fb, I see lots of
cache-line artifacts.
When I run kmstest (from kms++), I get a flood of list corruptions
somewhere in omap_gem. Is it related to "Deferred I/O is not compatible
with SHMEM"?
Tomi
