On Thu, Nov 01, 2012 at 03:54:55PM +0530, Jayachandran C. wrote: > On Wed, Oct 31, 2012 at 02:28:50PM +0100, Ralf Baechle wrote: > > On Wed, Oct 31, 2012 at 06:31:29PM +0530, Jayachandran C wrote: > > > > > Disable PGD_C0_CONTEXT option for XLP, which does not work. > > > > Why does this not work on XLP? > > > > I see a kernel crash around the time init starts, planning to > look at this next. For now, I thought I will enable R2 and disable > PGD_C0_CONTEXT so that we get the rest of the R2 stuff for XLP. On XLP the XContext PTEbase is [63:55], but the current code tries to use XContext [63:48] to store the processor ID, which will not work. I can probably work around the issue by changing the shift from 51 to 58, but that would not leave enough space for the 128 cpu config we want to support. I will send patch to fix this and to use the XLP c0 scratch registers (cop0 $22) in the tlb handlers. But until the PGD_C0_CONTEXT code is updated, this patch is probably the best solution. JC.
