On Thu, Apr 27, 2017 at 12:59:40PM -0500, Matt Weber wrote: > This patch updates the machine check handler of Linux kernel to > handle the e6500 architecture case. In e6500 core, L1 Data Cache Write > Shadow Mode (DCWS) register is not implemented but L1 data cache always > runs in write shadow mode. So, on L1 data cache parity errors, hardware > will automatically invalidate the data cache but will still log a > machine check interrupt. > > Signed-off-by: Ronak Desai <ronak.de...@rockwellcollins.com> > Signed-off-by: Matthew Weber <matthew.we...@rockwellcollins.com> > --- > arch/powerpc/include/asm/reg_booke.h | 1 + > arch/powerpc/kernel/traps.c | 12 ++++++++++-- > 2 files changed, 11 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/include/asm/reg_booke.h > b/arch/powerpc/include/asm/reg_booke.h > index 737e012..c811128 100644 > --- a/arch/powerpc/include/asm/reg_booke.h > +++ b/arch/powerpc/include/asm/reg_booke.h > @@ -196,6 +196,7 @@ > #define SPRN_DEAR 0x03D /* Data Error Address Register */ > #define SPRN_ESR 0x03E /* Exception Syndrome Register */ > #define SPRN_PIR 0x11E /* Processor Identification Register */ > +#define SPRN_PVR 0x11F /* Processor Version Register */ > #define SPRN_DBSR 0x130 /* Debug Status Register */ > #define SPRN_DBCR0 0x134 /* Debug Control Register 0 */ > #define SPRN_DBCR1 0x135 /* Debug Control Register 1 */
This is already defined in asm/reg.h > @@ -545,8 +546,15 @@ int machine_check_e500mc(struct pt_regs *regs) > * may still get logged and cause a machine check. We should > * only treat the non-write shadow case as non-recoverable. > */ > - if (!(mfspr(SPRN_L1CSR2) & L1CSR2_DCWS)) > - recoverable = 0; > + /* On e6500 core, L1 DCWS (Data cache write shadow mode) bit is > + * not implemented but L1 data cache is by default configured > + * to run in write shadow mode. Hence on data cache parity > errors > + * HW will automatically invalidate the L1 Data Cache. > + */ Please wrap at under 80 columns. "default" implies it can be changed, so: s/is by default configured to run in write shadow mode/always runs in write shadow mode/ Otherwise looks good. -Scott
