On Mon, Oct 12, 2009 at 01:20:49PM -0700, Gandham, Raghu wrote:
> > -----Original Message-----
> > From: Ralf Baechle [mailto:ralf@linux-mips.org]
> > Sent: Monday, October 12, 2009 9:18 AM
> > To: Gandham, Raghu
> > Cc: Kevin D. Kissell; linux-mips@linux-mips.org; Dearman, Chris
> > Subject: Re: [PATCH 15/15] Do not rely on the initial state
> > of TC/VPEbindings when doing cross VPE writes
> >
> > On Thu, Jul 02, 2009 at 02:46:33PM -0700, Gandham, Raghu wrote:
> >
> > > > From: Kevin D. Kissell [mailto:kevink@paralogos.com]
> > > > Sent: Wednesday, July 01, 2009 9:02 PM
> > > > To: Gandham, Raghu
> > > > Cc: linux-mips@linux-mips.org; Dearman, Chris
> > > > Subject: Re: [PATCH 15/15] Do not rely on the initial state of
> > > > TC/VPE bindings when doing cross VPE writes
> > > >
> > > > Note that, regardless of the reset state, smtc_configure_tlb()
> > > > should have at least temporarily bound TC 1 to VPE1, which may be
> > > > why this never seemed to be a problem on the 34K. If one
> > wants to
> > > > support designs with more than 2 VPEs, then this is
> > probably one of
> > > > the things that needs to be fixed. That having been said, rather
> > > > than adding a usually-redundant write_vpe_c0_vpeconf0() in that
> > > > clause, wouldn't it
> > > be
> > > > cleaner to just move the MVP setting from the top of the
> > loop to the
> > > > point in the loop just after the TCs have been bound to
> > the VPE in
> > > > question, i.e.,
> > > >
> > > > 454 if (slop) {
> > > > 455 if (tc != 0) {
> > > > 456 smtc_tc_setup(vpe,tc, cpu);
> > > > 457 cpu++;
> > > > 458 }
> > > > 459 printk(" %d", tc);
> > > > 460 tc++;
> > > > 461 slop--;
> > > > 462 }
> > > >
> > > >
> > write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0()
> > > > | VPECONF0_MVP);
> > > >
> > > > 463 if (vpe != 0) {
> > > > 464 /*
> > > > 465 * Clear any stale software
> > interrupts
> > > from
> > > > VPE's Cause
> > > > 466 */
> > > >
> > > > This should definitely be OK for a 34K, because it's
> > being executed
> > > > by TC0 in VPE0 and the reset state of VPE0 has MVP set. If it
> > > > weren't,
> > > > smtc_configure_tlb() would have failed.
> > > >
> > > > Regards,
> > > >
> > > > Kevin K.
> > >
> > >
> > > I will resend this patch with your suggestion.
> >
> > Ping? Don't think I ever received that, if you sent it.
> I resent the patch and it got checked-in. It is not appended to this
> mail thread though.
> http://www.linux-mips.org/git?p=linux.git;a=commitdiff;h=d8e5f9fe5dab0e0
> 7985f2456cb6cc57788f53131
Ah, ok. Thanks!
Ralf
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