powerpc/e500: fix breakage with fsl_rio_mcheck_exception

The wrong MCSR bit was being used on e500mc.  MCSR_BUS_RBERR only exists
on e500v1/v2.  Use MCSR_LD on e500mc, and remove all MCSR checking
in fsl_rio_mcheck_exception as we now no longer call that function
if the appropriate bit in MCSR is not set.

If RIO support was enabled at compile-time, but was never probed, just
return from fsl_rio_mcheck_exception rather than dereference a NULL
pointer.

TODO: There is still a remaining, though comparitively minor, issue in
that this recovery mechanism will falsely engage if there's an unrelated
MCSR_LD event at the same time as a RIO error.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This commit is contained in:
Scott Wood 2011-06-16 14:09:17 -05:00 committed by Kumar Gala
parent f3fed682f7
commit 82a9a4809f
2 changed files with 18 additions and 17 deletions

View file

@ -425,7 +425,7 @@ int machine_check_e500mc(struct pt_regs *regs)
unsigned long reason = mcsr;
int recoverable = 1;
if (reason & MCSR_BUS_RBERR) {
if (reason & MCSR_LD) {
recoverable = fsl_rio_mcheck_exception(regs);
if (recoverable == 1)
goto silent_out;

View file

@ -283,23 +283,24 @@ static void __iomem *rio_regs_win;
#ifdef CONFIG_E500
int fsl_rio_mcheck_exception(struct pt_regs *regs)
{
const struct exception_table_entry *entry = NULL;
unsigned long reason = mfspr(SPRN_MCSR);
const struct exception_table_entry *entry;
unsigned long reason;
if (reason & MCSR_BUS_RBERR) {
reason = in_be32((u32 *)(rio_regs_win + RIO_LTLEDCSR));
if (reason & (RIO_LTLEDCSR_IER | RIO_LTLEDCSR_PRT)) {
/* Check if we are prepared to handle this fault */
entry = search_exception_tables(regs->nip);
if (entry) {
pr_debug("RIO: %s - MC Exception handled\n",
__func__);
out_be32((u32 *)(rio_regs_win + RIO_LTLEDCSR),
0);
regs->msr |= MSR_RI;
regs->nip = entry->fixup;
return 1;
}
if (!rio_regs_win)
return 0;
reason = in_be32((u32 *)(rio_regs_win + RIO_LTLEDCSR));
if (reason & (RIO_LTLEDCSR_IER | RIO_LTLEDCSR_PRT)) {
/* Check if we are prepared to handle this fault */
entry = search_exception_tables(regs->nip);
if (entry) {
pr_debug("RIO: %s - MC Exception handled\n",
__func__);
out_be32((u32 *)(rio_regs_win + RIO_LTLEDCSR),
0);
regs->msr |= MSR_RI;
regs->nip = entry->fixup;
return 1;
}
}