In article <200211030456.gA34u7h16089@pl374.nas911.nara.nttpc.ne.jp>
itohy@netbsd.org wrote:

> > (1) it does not clear VPN
> 
> I don't think it is a problem.
> The V (valid) and D (dirty) bits are cleared by either way,
> and the VPN shall not make sense if an entry is not valid

Yeah, but I just think it is safe and is the difference
between AA and DA1.

> Possibly, an errata or something?

AFAIK, there is no errata on the Hitachi's web site.

> Mmm, I tried
> 
> (c) VA = 0xf0000000 (causes reset)
> 	for (e = 0; e < eend; e++) {
> 		a = SH4_UTLB_AA | (e << SH4_UTLB_E_SHIFT);
> 		_reg_write_4(a, 0xf0000000);
> 	}
> 
> and no improvement.

My dc also has a problem of ramdom reboot on heavy load,
and I tried the similar patch but it did not solve the problem.
Maybe some other problems are there..

BTW, all these TLB operation should be protected by splvm() or not?
I'm now testing a kernel with sprinkled splvm() in sh3/pmap.c.
---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp