On Mon, 2003-03-31 at 11:24, Hartvig Ekner wrote:
> Hi Eric,
>
> I did a quick check of a complete kernel disassembly, and there are
> tons of direct or indirect RMW's to config, which do not explicitly
> insure that Config[0D] is set.
> Pete - are you aware of this?
Config[OD] is set in setup.c and should not be cleared afterward.
> Thus, there seems to be a potential problem lurking here for anybody
> who is using USB.
>
> However, I am not using USB at all, and it is configured out of the
> kernel. So I assume this is not errata #3 we're seeing here?
>
> So, to summarize: The first set of problems in my email below seem to
> be fully explained by errata #14. Note that any kernel compiled from
> the current CVS exhibits this problem:
> Because although NONCOHEHENT_IO is set, the NC bit in PCI_CFG is not
> set.
Hmm, ok, I'll check that out.
> I have verified that the problem occurs when NC is cleared, regardless
> of the .config option. So some code needs to be changed in
> au1000/xxx/setup.c... (set NC if NONCOHERENT_IO
> is enabled).
> But - much wore worrisome: I did this modification, and with the NC
> bit set, and NONCOHERENT_IO set, I get the second set of errors,
> although it takes much longer time. The wback_inv calls are made
> through the generic code in the subroutine
> pci_alloc_consistent() (in arch/mips/kernel/pci-dma.c).
> So something is wrong.... Anybody at AMD who would care to continue
> the debug?
Can you send me your test and exact instructions on how you're
duplicating the error? I won't have time to look at it until after 4/20
though.
Pete
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