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Re: better late than never: amigappc progress

On Thu, 11 Feb 2010 21:16:48 +0100 Frank Wille wrote:
> No surprise. I just asked if somebody owns a BPPC, not that amigappc is
> already working on it... ;)

One can hope...

> > Enforcer shows hits to 0xfff03100+.
> Hits while accessing this address, or from a program running there?
> The 68k-part of the kernel startup routine is located at 0xfff03000,
> which will copy the kernel to 0x08000000 (probably this is causing the
> hits on an A1200).

First from writing to that address and then from trying to execute from there, 
if I read it right. What memory should be at 0xfff03000?

I put the log up here:

When running with Enforcer gobsdppc actually gets a bit further than without it.
It prints following line and then resets the display before getting stuck:

Booting Single-User...Using 32256K FASTMEM at 0x76000000, 2M CHIPMEM

So I guess it did detect the fast memory.

> I never owned an A1200 and I know nothing about the memory mapping in
> BPPC cards. Is the address space allocated from 0x80000000 down or from
> 0x70000000 up? Is it always the same with all BPPC verions?

No idea on the general case, but I get lots of variations just on my machine.
There are two memory slots on the BPPC. I tried with two different SIMMs. 

As reported by Enforcer's VERBOSE option:
  ROM Physical:   $00F80000  Size: $00080000 (512K)       Type=$FF CACHEABLE
  Memory Address: $76000020  Size: $01F7FFE0 (32255K)     Type=$00 CACHEABLE
  Memory Address: $00001020  Size: $001FEFE0 (2043K)      Type=$02 CACHE 
  Board Address:  $00F00C04  Size: $00020000 (128K)       Type=$D2 CACHE 
  CARD Detected: $00600000   Size: $00440002 (4352K)               CACHE 
32MB in other slot (I'm omitting the unchanged lines):
  Memory Address: $78000020  Size: $01F7FFE0 (32255K)     Type=$00 CACHEABLE
  Memory Address: $57C00020  Size: $0037FFE0 (3583K)      Type=$00 CACHEABLE
4MB in other slot:
  Memory Address: $68000020  Size: $0037FFE0 (3583K)      Type=$00 CACHEABLE

That 128K seems to be BVisionPPC as it only shows up when BVPPC is connected.

> To make it work at least three locations have to be changed:
> - set TEXTADDR in conf/std.amigappc to 0x76000000
> - initialize a BAT for A1200 fast memory in amigappc/machdep.c initppc()
> - change gobsdppc to copy the kernel to 0x7600000
> Of course gobsdppc and the kernel should autodetect a BPPC and a CSPPC
> in the next step. The kernel should have a common base address. Maybe
> we could use the BATs to always translate all fast mem accesses to
> 0x10000000? I can make some tests in the next days.

... autodetection sounds good. :)

-- jukka

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