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    SubjectRe: Linux 2.4.21-pre3-ac4
    On Sun, 2003-01-12 at 21:27, Alan Cox wrote:

    > which currently has two problems Ross found
    > 1. The processors or so fast we have to enforce the 400nS delay nowdays

    What about PCI write posting ? How can we enforce the 400ns delay here ?
    I suspect we can't read back from the taskfile registers after writing
    the command. Especially when using DMA, I think I remember Andre telling
    me even tapping alt status might not be safe... So we need to issue
    a read from the same bus path, but not on any taskfile register from
    this channel... hrm... any idea ?

    > 2. The code is racey in some situations with a shared IRQ because we
    > may get an IRQ after we set the handler but before we send the command,
    > or implemnted the other way the command can complete before we set the
    > handler.

    Yup, that's an old problem indeed.


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