[LinuxBIOS] Winflashrom -- Current Status

Peter Stuge peter at stuge.se
Thu Jul 12 17:27:35 CEST 2007

On Thu, Jul 12, 2007 at 05:13:38PM +0700, Darmawan Salihun wrote:
> > As for the EPIA board, well, where is that base specified? In a
> > PCI config register or where?
> The base is in a PCI config register. Relevant code as follows:
>     base = pci_read_word(dev, 0x88) & 0xFF80;
>     val = inb(base + 0x4D);
>     val |= 0x80;
>     outb(val, base + 0x4D);

Ok! Put all of board_enable.c in the kernel driver and add some way
for the app to call any function in the board_pciid_enables list, in
the kernel driver. Sort of RPC but over a app/kernel split instead of
over a network.

Then compile board_enable.c also into the app, but not to call any of
the functions (which would fail anyway) but only to get the same
board_pciid_enables list. The struct may have to be extended to have
a unique index for each entry so that the driver and app can agree on
which function is which.

All of the device detection should be done where it is easiest to do
it. Since the driver will need to do safe PCI accesses for board
enables perhaps it makes sense to contain all PCI accesses in the

On the other hand, perhaps the app will need to do some PCI accesses
to choose the right board_enable function and then it's better to do
most of them in the app.

What do you think?

Another general matter, make sure the app and driver can exchange
version numbers. That way both the driver and the app could have
compatiblity code in order to be backwards compatible.

I would like the app to exit with an error message if it can't agree
with the kernel driver on a "protocol version" that both of them
support. Need not be fancy right now, a simple two-way version check
is plenty good.


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