4.0 Beta PC version problems

[Joel Sherrill]

On Tue, 21 Jul 1998, Brian Stevens wrote:

> I have built the i386-pc version of rtems and produced a bootable 
> image using grub.  However, the bootdisc will not work on one type of 
> PC (Dell Optiplex 466/MX) but seems to work ok on the other types I 
> have tried it on.
> 
> The steps are as follows :-
> 
> 1) Boot machine
> 2) Loads GRUB
> 3) Select Hello world test from grub memu
> 4) Kernel = (fd0)/hello.exe message
> 5) Loading message appears - Loading: [format=NetBSD-a.out, 
> loadaddr=0x100000, text=0x16d60, C, data=0xde4, bss=0x3c74, 
> entry=0x100000]
> 
> 6) system hangs.
> 
>  Unfortunately the spare PCs that I have available 
> for use with RTEMS are Optiplex 466/MX
> 
> Does any one have any suggestions.

The pc386 BSP has had problems in the past with certain combinations of
video cards.  Mostly it is the placement of the video RAM.  

There are a number of debug printk's in the BSP which can help point out
where the problem is.  At the bottom of bspstart.c there is an if 0 around
a section which prints a lot of memory information and "defining
DEBUG_EARLY_STAGE" will enable some more information.  In particular, it
will print out the address information being used by the console driver.

Ironically the BSP was developed on older hardware and initially had
trouble with newer PCs.

--joel