[PATCH 09/21] powerpc/powernv: Clear PAPR error injection registers
From: Gavin Shan <hidden>
Date: 2014-09-30 02:39:17
Subsystem:
linux for powerpc (32-bit and 64-bit), pci enhanced error handling (eeh) for powerpc, the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Mahesh J Salgaonkar, Linus Torvalds
The frozen state on one specific PE is probably caused by error injection, which is done with help of PAPR error injection registers. According to the hardware spec, those registers should be cleared automatically after one-shot frozen PE. However, that's not always true, at least on P7IOC of Firebird-L. So we have to clear them before doing PE reset to avoid recursive EEH errors at recovery stage. Signed-off-by: Gavin Shan <redacted> --- arch/powerpc/platforms/powernv/eeh-ioda.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)
diff --git a/arch/powerpc/platforms/powernv/eeh-ioda.c b/arch/powerpc/platforms/powernv/eeh-ioda.c
index 3389cf0..e516b7f 100644
--- a/arch/powerpc/platforms/powernv/eeh-ioda.c
+++ b/arch/powerpc/platforms/powernv/eeh-ioda.c@@ -682,6 +682,31 @@ static int ioda_eeh_reset(struct eeh_pe *pe, int option) if (pe->type & EEH_PE_PHB) { ret = ioda_eeh_phb_reset(hose, option); } else { + struct pnv_phb *phb; + s64 rc; + + /* + * The frozen PE might be caused by PAPR error injection + * registers, which are expected to be cleared after hitting + * frozen PE as stated in the hardware spec. Unfortunately, + * that's not true on P7IOC. So we have to clear it manually + * to avoid recursive EEH errors during recovery. + */ + phb = hose->private_data; + if (phb->model == PNV_PHB_MODEL_P7IOC && + (option == EEH_RESET_HOT || + option == EEH_RESET_FUNDAMENTAL)) { + rc = opal_pci_reset(phb->opal_id, + OPAL_PHB_ERROR, + OPAL_ASSERT_RESET); + if (rc != OPAL_SUCCESS) { + pr_warn("%s: Failure %lld clearing " + "error injection registers\n", + __func__, rc); + return -EIO; + } + } + bus = eeh_pe_bus_get(pe); if (pci_is_root_bus(bus) || pci_is_root_bus(bus->parent))
--
1.8.3.2