Hello,
Sorry, that last email escaped from me before I was done. :-)
Anyway, I was fooling around with disabling the BIOS on my PDC20265
Promise Ultra100 PCI card, to speed up my booting. When I did that, the
pdc202xx driver only configures the chipset for mdma2, not for udma5.
Poking around a bit, I discovered that the CONFIG_PDC202XX_BURST option
does exactly what I need--it tells the pdc202xx driver to configure the
chipset for UDMA regardless of how it found it.
So here is an updated Configure.help entry that makes it clearer what
CONFIG_PDC202XX_BURST does.
Cheers,
Wayne
--- linux-2.4.15-pre3/Documentation/Configure.help Sun Nov 11 22:11:25 2001
+++ linux-2.4.15-pre3-ide/Documentation/Configure.help Mon Nov 12 09:56:59 2001
@@ -1112,11 +1112,13 @@
Special UDMA Feature
CONFIG_PDC202XX_BURST
- For PDC20246, PDC20262, PDC20265 and PDC20267 Ultra DMA chipsets.
- Designed originally for PDC20246/Ultra33 that has BIOS setup
- failures when using 3 or more cards.
+ This option causes the pdc202xx driver to enable UDMA modes on the
+ PDC202xx even when the PDC202xx BIOS has not done so.
- Unknown for PDC20265/PDC20267 Ultra DMA 100.
+ It was originally designed for the PDC20246/Ultra33, whose BIOS will
+ only setup UDMA on the first two PDC20246 cards. It has also been
+ used succesfully on a PDC20265/Ultra100, allowing use of UDMA modes
+ when the PDC20265 BIOS has been disabled (for faster boot up).
Please read the comments at the top of
<file:drivers/ide/pdc202xx.c>.