[PATCH 2/2] 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

   Fix is to set the performance register (0x2f) with a more stable value.

   From: Antonino Daplas [off-list ref]
   Signed-off-by: Antonino Daplas [off-list ref]
---

tridentfb.c |    2 +-
1 files changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/video/tridentfb.c
+++ b/drivers/video/tridentfb.c

@@ -904,7 +904,7 @@ static int tridentfb_set_par(struct fb_i

	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 */




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On Mon, 1 Aug 2005, Antonino A. Daplas wrote:

   Fix is to set the performance register (0x2f) with a more stable value.

Applied. However, the patch was whitespace-damaged, please don't do that. 
I fixed it up by hand this time.

		Linus


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