Re: [PATCH] x86: provide a DMI based port 0x80 I/O delay override.

From: Rene Herman
Date: Sun Dec 16 2007 - 21:17:36 EST


On 17-12-07 03:04, H. Peter Anvin wrote:

Rene Herman wrote:
On 17-12-07 00:12, David P. Reed wrote:

Rene Herman wrote:
David: I've plugged in your DMI values in this. Could you perhaps test this to confirm that it works for you?

Will test it by tomorrow morning.

Might as well test the new version then. Ingo Molnar requested a few changes and this fixes a couple of problems as well.


As far as I can tell, the code still uses udelay() before calibration if io_delay=udelay?

Just so we're clear on that...

Yes. This patch is explicitly about the alternate port and not about udelay. As discussed (and changelogged) the calibration is just one problem with PCI posting and possible SMP races the other ones. Ingo Molnar wanted it as a debugging thing already though.

Once we start discussing udelay() again I believe we should go with the simple per CPU-Family loops_per_jiffy initialization to fix that first problem (and I guess I could hack that in now) but then the bigger problem remains and will need a fair amount of testing at least and mostly on machines that are by now gathering dust in a few basements...

Rene


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