Re: Exposing ROM's though sysfs

From: Jesse Barnes (jbarnes_at_engr.sgi.com)
Date: 07/30/04

  • Next message: Tim Waugh: "Re: [PATCH] Gigabit Ethernet support for forcedeth" 
    To: Jon Smirl <jonsmirl@yahoo.com>
Date:	Fri, 30 Jul 2004 10:10:29 -0700

    On Friday, July 30, 2004 9:53 am, Jon Smirl wrote:
    > We talked at OLS about exposing adapter ROMs via sysfs. I have some
    > time to work on this but I'm not sure about the right places to hook
    > into the kernel.

    How about this patch?

    > The first problem is recording the boot video device. This is needed
    > for laptops that compress their video and system ROMs together into a
    > single ROM. When sysfs exposes the ROM for these adapters it needs to
    > know the boot video device so that it can return the ROM image at
    > C000:0 instead of trying to find an actual ROM. What is the right
    > kernel structure for recording the boot video device? Where should this
    > code live? It is probably x86 specific but have non-x86 laptops done
    > the same trick?

    If we have the pci quirks stuff fill in pci_dev->resource[PCI_ROM_RESOURCE]
    with the right addresses, we should be ok.

    > What about ISA support. Should we make an attempt to return ROM
    > contents from ISA cards?

    That's probably more trouble than it's worth, but if someone really wants it
    they could always code it up.

    > Note that not just video cards can have ROMs. Disk adapters commonly
    > have them too. We probably want to expose these ROMs too.
    >
    > Do we want to expose the system ROM via sysfs? Where should it appear?
    >
    > Some Radeon cards have a bug where they forgot to clear a latch which
    > makes the ROMs visible. Where should a fix for things like this go? I
    > can put it in the radeon driver but if you try to read the ROM before
    > the driver is loaded, the ROM won't be visible.

    Jesse

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  • Next message: Tim Waugh: "Re: [PATCH] Gigabit Ethernet support for forcedeth"

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