[PATCH] tridentfb: Fix scrolling artifacts during disk IO
Reported by: Jochen Hein (Bugzilla Bug 4312)
When there is disk I/O happening, the framebuffer has a little snow on
the screen. Once I/O has finished, no garbage remains on screen.
This bug was explained by: Knut Petersen
Most important is CRTC register 2f, signal quality is also improved for
higher vclk values by changing set_vclk() according to the X drivers and
cyblafb.c
The fix is to set the performance register (0x2f) with a more stable
value.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/video/tridentfb.c b/drivers/video/tridentfb.c
index 64aa78c..698ca92 100644
--- a/drivers/video/tridentfb.c
+++ b/drivers/video/tridentfb.c
@@ -904,7 +904,7 @@
write3X4(DRAMControl, tmp); //both IO,linear enable
write3X4(InterfaceSel, read3X4(InterfaceSel) | 0x40);
- write3X4(Performance,0x20);
+ write3X4(Performance,0x92);
write3X4(PCIReg,0x07); //MMIO & PCI read and write burst enable
/* convert from picoseconds to MHz */