linux/drivers/video/fbdev/matrox
Mikulas Patocka 972754cfae matroxfb: perform a dummy read of M_STATUS
I had occasional screen corruption with the matrox framebuffer driver and
I found out that the reason for the corruption is that the hardware
blitter accesses the videoram while it is being written to.

The matrox driver has a macro WaitTillIdle() that should wait until the
blitter is idle, but it sometimes doesn't work. I added a dummy read
mga_inl(M_STATUS) to WaitTillIdle() to fix the problem. The dummy read
will flush the write buffer in the PCI chipset, and the next read of
M_STATUS will return the hardware status.

Since applying this patch, I had no screen corruption at all.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-05-23 13:44:25 +03:00
..
g450_pll.c
g450_pll.h
i2c-matroxfb.c
Makefile
matroxfb_accel.c
matroxfb_accel.h
matroxfb_base.c
matroxfb_base.h
matroxfb_crtc2.c
matroxfb_crtc2.h
matroxfb_DAC1064.c
matroxfb_DAC1064.h
matroxfb_g450.c
matroxfb_g450.h
matroxfb_maven.c
matroxfb_maven.h
matroxfb_misc.c
matroxfb_misc.h
matroxfb_Ti3026.c
matroxfb_Ti3026.h