linux_dsm_epyc7002/drivers/gpu
Jordan Crouse 88b333b0ed drm/msm: Ensure that the hardware write pointer is valid
Currently the value written to CP_RB_WPTR is calculated on the fly as
(rb->next - rb->start). But as the code is designed rb->next is wrapped
before writing the commands so if a series of commands happened to
fit perfectly in the ringbuffer, rb->next would end up being equal to
rb->size / 4 and thus result in an out of bounds address to CP_RB_WPTR.

The easiest way to fix this is to mask WPTR when writing it to the
hardware; it makes the hardware happy and the rest of the ringbuffer
math appears to work and there isn't any point in upsetting anything.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
[squash in is_power_of_2() check]
Signed-off-by: Rob Clark <robdclark@gmail.com>
2016-12-29 15:02:58 -05:00
..
drm drm/msm: Ensure that the hardware write pointer is valid 2016-12-29 15:02:58 -05:00
host1x gpu: host1x: Add locking to syncpt 2016-11-11 15:33:13 +01:00
ipu-v3 imx-drm plane update cleanup, YUV formats 2016-11-11 09:31:27 +10:00
vga vgaarb: use valid dev pointer in vgaarb_info() 2016-11-22 16:40:35 +01:00
Makefile