[Qemu-devel] Re: 4xx booting into Linux userspace

[Andrew May]

On Sat, 17 Jan 2009 00:25:13 -0800
Andrew May <address@hidden> wrote:

> I finally got a 405 linux kernel booted into userspace.
> The op_helper change is pretty straight forward, where the "tlb->attr"
> values should have been set from the tlbwe_lo function instead of the
> high function.
> I am not sure that the tlb->attr bits completely line up with the
> tlbwe_lo bits, since I don't know how else they are used besides the
> zone bits.
> 
> For the helper.c I am not sure on the best way to deal with things.
> The first change should be ok, where the zone mapping was just off.
> But the other part where the 405 SPR doesn't seem to match up with
> SPR's used in the core TLB lookup code.

Just after I sent this I realized I didn't include the older patches I
had posted to the list on getting the 4xx stuff going. And then when I
tried to sync to the lastest I hit a snag with the display changes.

I feel pretty good about all the op_helper.c fixes.
1. Don't abort on Little endian pages, if they aren't valid.
2. Fix tlb->attr to get setting from lo reg instead of the high one.
3. Allow 4xx_tlbwe_lo, writes to leave the "tlb->prot valid" bit set,
and invalid pages to get the updates.

I don't know the best way to handle the spr SPR_DAR vs SPR_40x_DEAR
difference in helper.c

So if anyone knows the best way to address this, please let me know.

And I am not on the list so, please CC me.

Thanks.

4xx_working.patch
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