Messages in this thread | | | Subject | Re: [PATCH] via82cxxx IDE: Support multiple controllers | From | Alan Cox <> | Date | Thu, 13 Oct 2005 12:45:17 +0100 |
| |
On Mer, 2005-10-12 at 18:52 +0100, Alan Cox wrote: > On Mer, 2005-10-12 at 16:57 +0100, Daniel Drake wrote: > > Uh, looks like the kernel just assumes 33mhz unless overriden by the user. Is > > this assumption generally accurate? > > If it is not, then there's probably no point displaying timing info... > > A small number of 486 systems use 25Mhz, some boards allow overclock at > 37.5Mhz on the PCI. I've been looking at this the past couple of days > for the libata via driver which I've been porting over and unfortunately > having been through the Northbridge manuals I can find no way to ask the > chipset what the PCI clock is set too.
Ok I found what seems to be a pattern for the early chipsets with 25MHz support.
If the bus speed of your 486 is 25Mhz the chipset is at 25MHz as is your IDE (ie 486/25, DX2/50, 3/75 - not sure about 4/100 etc). Now does anyone know how you find out if the CPU is 25MHz bus clocked on a 486 8)
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |