On Mon, Jun 27, 2016 at 10:55:03AM -0500, alar...@ddci.com wrote: > David Gibson <da...@gibson.dropbear.id.au> wrote on 06/27/2016 12:32:13 > AM: > > > From: David Gibson <da...@gibson.dropbear.id.au> > > To: alar...@ddci.com > > Cc: ag...@suse.de, qemu-devel@nongnu.org, qemu-...@nongnu.org > > Date: 06/27/2016 12:30 AM > > Subject: Re: [PATCH] target-ppc: Eliminate redundant and incorrect > function booke206_page_size_to_tlb > > > > On Sun, Jun 26, 2016 at 09:38:03PM -0500, alar...@ddci.com wrote: > > > David Gibson <da...@gibson.dropbear.id.au> wrote on 06/26/2016 > 08:36:52 > > > PM: > > > > > > > From: David Gibson <da...@gibson.dropbear.id.au> > > > > To: Aaron Larson <alar...@ddci.com> > > > > Cc: ag...@suse.de, qemu-devel@nongnu.org, qemu-...@nongnu.org > > > > Date: 06/26/2016 08:58 PM > > > > Subject: Re: [PATCH] target-ppc: Eliminate redundant and incorrect > > > function booke206_page_size_to_tlb > > > > > > > > On Fri, Jun 24, 2016 at 12:11:00PM -0700, Aaron Larson wrote: > > > > > > > > > > Eliminate redundant and incorrect booke206_page_size_to_tlb > function > > > > > from ppce500_spin.c in preference to previously existing but newly > > > > > exported definition from e500.c > > > > > > > > > > Signed-off-by: Aaron Larson <alar...@ddci.com> > > > > > > > > Uh.. sorry.. can you provide a reference explaining why the removed > > > > version is wrong? Doesn't this depend on which MMU Architecture > > > > Version we're emulating? > > > > > > Sure, the code is internally inconsistent (shift assumed didn't match > > > shift defined). I will provide an update commit message, similar to > the > > > original posting I made a few days ago with the "direction" > > > corrected. > > > > Right, I can see that the two old versions were different, which was > > clearly wrong. What I'm looking for is an explanation of why the one > > you've picked is the right one, not the other one. > > How's this? > > Eliminate redundant and incorrect booke206_page_size_to_tlb function > from ppce500_spin.c in preference to previously existing but newly > exported definition from e500.c > > The booke206_page_size_to_tlb function in e500.c was updated in commit > 2bd9543cd303d9f6cbd37b7466bb03543035156b to reflect a change in the > definition of MAS1_TSIZE_SHIFT from 8 (corresponding to a min TLB page > size of 4kb) to a value of 7 (TLB page size 2k). The > booke206_page_size_to_tlb() function defined in ppce500_spin.c was > never updated to reflect the change in MAS1_TSIZE_SHIFT.
Ah, yes, that looks good. Except that the convention when citing
other commits is to just use the first 7 characters of the commit id,
but to include the 1 line description. So:
...commit 2bd9543 "ppc: booke206: use MAV=2.0 TSIZE definition, fix
4G pages" to reflect...
> In http://lists.nongnu.org/archive/html/qemu-ppc/2016-06/msg00533.html,
> Scott Wood suggested this "root cause" explanation:
>
> SW> The patch that changed MAS1_TSIZE_SHIFT from 8 to 7 was around the
> SW> same time as the patch that added this code, which is probably why
> SW> adjusting it got missed. Commit 2bd9543cd3 did update the
> SW> equivalent code in ppce500_mpc8544ds.c, which now resides in
> SW> hw/ppc/e500.c and has been changed to not assume a power-of-2
> SW> size. The ppce500_spin version should be eliminated.
>
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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