Re: Kernel 2.2.14

[Kevin Puetz <puetzk@iastate.edu>]

bh40@calva.net said:
> >OK, thanks. I was reluctant to make that guess on my own... > >Well,
> maybe with this I can build a working kernel again (so that I can
> debug  >why the serial port on my G3/233DT rev1). It will send but not
> recieve - at  >least, it never gets any data - no errors. strange...

Well, your v12 stuff still doesn't boot on my machine (I waited for it to see if I was just mis-applying your fix). But I found the problem - at least, I made a change and it works now. When looking at the diff from vger (which boots, but no working USB), I saw the following change in head.s (actually, this is my patch that fixed the problem, reverse it for the change that broke the kernel).

--- arch/ppc/kernel/head.S.bak  Tue Jan 18 14:40:12 2000
+++ arch/ppc/kernel/head.S      Tue Jan 18 17:15:57 2000
@@ -139,15 +139,16 @@
        .text
        .globl  _start
 _start:
+       .long   TOPHYS(__start),0,0
        /*
         * These are here for legacy reasons, the kernel used to
         * need to look like a coff function entry for the pmac
         * but we're always started by some kind of bootloader now.
         *  -- Cort
         */
-       nop
-       nop
-       nop
+/*     nop */
+/*     nop */
+/*     nop */

 /* PMAC
  * Enter here with the kernel text, data and bss loaded starting at

I don't however know enough to make this change intelligently - I just backed out that bit of the patch, and now 2.2.14 boots fine (and has been up for a couple of hours with X, net traffic, etc.). I assume it's related to yaboot or BootX? quik and/or my beige Rev 1 G3's firmware don't like the nops though, and wants the ".long   TOPHYS(__start),0,0". Should I cc paul with this? It's not your patch that's broken, it's his tree, but you were the one helping me before, so...

> You can try, at first, to edit macserial.c and change
> #define SUPPORT_SERIAL_DMA
> to 
> #undef SUPPORT_SERIAL_DMA 

That helped, though the behavior is still flakey. Now it works 'sometimes' for some definitions of sometimes :-). I'll work on it some more, now that I can make 2.2.14 boot.

Learning stuff I didn't even know I didn't know about the kernel.