Hello Alan, First things first. Tons of thanks for a mail FULLY LOADED with useful information. I'm still to digest it all, but really thanks.
>> > >> > I'm sure having a single driver for all the NICs is a feature cool >> > enough to die for. Yes, it might have drawbacks like just pointed out >> > by Peter, but surely a "single driver for all NIC" feature could prove >> > to be great in some systems. >> >
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> > Hi ... so there seem to be no technical feasibily issues, just > reliabliy / ugly design issues? So one can still go ahead and write a > Universal Protocol Driver that can work with all (PXE compatible) > NICs? With help from the Etherboot Project, I've recently implemented such a driver for Etherboot 5.4. It currently supports PIO NICs (e.g. cards that use in*/out* to interface with CPU). It's currently available in a branch, and will be merged into the trunk by the Etherboot project. It works reliably with QEMU + PXELINUX, with the virtual ne2k-pci NIC.
Umm ... pardon me if I am wrong, but I think you implemented a "UNDI Driver" (i.e. the code that provides implementation of UNDI API, and often resides in the NIC ROM) . I'm looking forward to write a "Universal Protocol Driver" (i.e. the code that will be a linux kernel module and will, use the UNDI API provided by your UNDI driver). But nevertheless your information has been *VERY* helpful ...
At minimum, one needs to be able to probe for !PXE presence, which means you need to map in 0-1MB of physical memory. The PXE stack's memory also needs to be mapped in. My UNDI driver relies on a kernel module, generic across all NICs, to accomplish these by mapping in the !PXE probe area and PXE memory in a user process.
I'm pretty newbie to PXE, but I I think !PXE structure is used to find out the location & size of PXE & UNDI runtime routines, by UNIVERSAL PROTOCOL DRIVERS. Is my understanding wrong? Also, I think that UNDI driver routine will need not call PXE routines (TFTP / DHCP etc) as UNDI routines would be at a lower level providing access to the bare bones hardware. Is this correct? Thanks, Dan - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs
