Eric W. Biederman wrote:
>I've just done some investigating, possibly duplicating work,
>and dug into the IDE spinup issue. My conclusion, the Linux kernel is
>buggy.
>
>IDE spinup is trivial. From my testing all you have to do
>is wait until the ide busy bit is clear, and then send
>commands. IDE drives do all of the hard work for you.
>
>The tricky part with IDE is to get a reliable drive detection
>routine, as this was not an initial design requirement.
>
>I believe I have accomplished that as well. What I do. After the
>busy bit is clear send the IDE channel a software reset. Then I read
>the signature bytes from each drive, and if the signature is correct
>I have found an IDE drive. I confirm this by read/writing some
>registers and veirfying the contents stick. This will require wider
>testing to confirm it really is reliable.
>
>After you know where you have drives running
>IDENTIFY_DEVICE/IDENTIFY_PACKET_DEVICE where appropriate is still
>needed to get the drive into a usable state. But having confirmed
>already that the drive exists this is much easier.
>
>Anyway after I do a little more code cleanup I will check this code
>into the LinuxBIOS tree.
>
>What I do know. My code handles IDE drive spinup when the kernel
>fails, and the kernel doesn't have any trouble after my code has run.
>
>Eric
>
Eric,
Did I send our patched etherboot with "perfect" IDE support ?? Or I
just sent to Ron ??
P.S. Actually, we are doing almost the same as what you described.
Ollie
