Subject: Re: port for Samsung S3C4510B (ARM7TDMI)
To: None <port-arm@netbsd.org>
From: =?iso-8859-15?q?J=F6rn_Seger?= <joern.seger@udo.edu>
List: port-arm
Date: 09/10/2004 09:19:24
Hi all,

There is a catch in it: One small sentence in the user manual:
The KS32C6200 does not have an external coprocessor interface. It does not=
=20
have a on-chip coprocessor also.
Sound not very exciting, but that means you can't use the coprocessor p15.
Exciting is that the coprocessor p15 is used for the MMU:

from arm/arm/cpufunc_arm7tdmi.S:

=2D--- snipp ------------
ENTRY(arm7tdmi_setttb)
        mov     r1, r0          /* store the TTB in a safe place */
        mov     r2, lr          /* ditto with lr */

        bl      _C_LABEL(arm7tdmi_cache_flushID)

        /* Write the TTB */
        mcr     p15, 0, r1, c2, c0, 0 <---- !!!!!!!!!!
=2D--- snipp -------------

Thats it on that topic - regards=20

J=F6rn

Am Montag, 6. September 2004 16:26 schrieb Richard Earnshaw:
> On Mon, 2004-09-06 at 15:03, J=F6rn Seger wrote:
> > Some additions:
> >
> > 1) The CPU is based on the ARM7TDMI design
> >
> > 2) When I grep arround in the code, I found some CPU_ARM7TDMI define
> > areas in "arm/cpufunc.*". So I believe CPU/MMU and TLB is basicly
> > supported. Am I right?
> >
> > My questions:
> > Would it just be the addition of
> > options	CPU_ARM7TDMI
> > in the kernel config to add the CPU-support?
>
> It should be, but I can't off-hand see a committed port that uses this
> CPU, so can't give any guarantee that it works correctly.
>
> > On what port should I base this addition?
>
> A (very) quick glance at the product guide for the chip suggests it
> *might* be similar to the evbarm configs for Sumsung's arm9 devices,
> based on the S3C2XXX, so the SMDK2410 and SMDK2800 might prove to be a
> good starting point.
>
> R.