Re: PROBLEM: boot hang on Indy R4400SC (regression)

[Thomas Bogendoerfer]

On Sat, Nov 08, 2025 at 03:02:17PM -0500, Nick Bowler wrote:
> On Fri, Nov 07, 2025 at 03:12:31PM -0500, Nick Bowler wrote:
> > On Fri, Nov 07, 2025 at 07:29:25PM +0000, Jiaxun Yang wrote:
> > > Unfortunately my Indy won't go over ARCS prom so I'm not in a position
> > > to debug this on my side. I have inspected the code again and I can't
> > > see anything preventing it to work on R4000 family.
> > 
> > I'll try adding some extra prints to at least figure out where it is
> > actually hanging.
> 
> I did not have much success with adding prints, but looking more closely
> at the console output it seems that what is ultimately failing is the
> SCSI bus enumeration which does not complete unless I revert commit
> 35ad7e181541.

the problem is the tlb_probe() r4k_tlb_uniquify(), if the TLB contains

Index:  0 pgmask=4kb va=80000000 asid=00
	[pa=00000000 c=0 d=0 v=0 g=0] [pa=00000000 c=0 d=0 v=0 g=0]
Index:  1 pgmask=4kb va=80000000 asid=00
	[pa=00000000 c=0 d=0 v=0 g=0] [pa=00000000 c=0 d=0 v=0 g=0]
Index:  2 pgmask=4kb va=80000000 asid=00
	[pa=00000000 c=0 d=0 v=0 g=0] [pa=00000000 c=0 d=0 v=0 g=0]
Index:  3 pgmask=4kb va=80000000 asid=00
	[pa=00000000 c=0 d=0 v=0 g=0] [pa=00000000 c=0 d=0 v=0 g=0]
Index:  4 pgmask=4kb va=80000000 asid=00
	[pa=00000000 c=0 d=0 v=0 g=0] [pa=00000000 c=0 d=0 v=0 g=0]
[...]

which is coming from the Indy PROM. I only tested this patch on an R5k
Indy and the R5000 CPU doesn't have a problem with this.

I'm working on a fix for this.

Thomas.

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