again 2.3.28

David N. Welton davidw at
Thu Nov 18 06:53:40 EST 1999

On Wed, Nov 17, 1999 at 11:43:40AM -0800, Ani Joshi wrote:

> On Wed, 17 Nov 1999, David N. Welton wrote:

> > So, we can't use prom_print to print checkpoints and we can't use
> > printk yet.
> you can use prom_print to print until start_kernel, 

This is from arch/ppc/kernel/prom.c :

 * Because OF may have mapped I/O devices into the area starting at
 * KERNELBASE, particularly on CHRP machines, we can't safely call
 * OF once the kernel has been mapped to KERNELBASE.  Therefore all
 * OF calls should be done within prom_init(), and prom_init()
 * and all routines called within it must be careful to relocate
 * references as necessary.

This is indeed a CHRP machine, an RS6K F50, to be precise.

So, according to the people who wrote this code, you cannot do that.

> then you can use printk because console_init() is done very early
> (unless its dieing before that which would really suck), but i'm
> pretty sure you should be able to prom_print until then.  how are
> you calling your prints?

I was calling them with 'bl myfunc', which was defined as void myfunc
() and contained a call to prom_print.

David N. Welton, Developer, Linuxcare, Inc.
415.354.4878 x241 tel, 415.701.7457 fax
davidw at,
Linuxcare. At the center of Linux.

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