| Message ID | 20190311115233.6514-3-s.miroshnichenko@yadro.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | powerpc/powernv/pci: Make hotplug self-sufficient, independent of FW and DT | expand |
On Mon, Mar 11, 2019 at 10:52 PM Sergey Miroshnichenko <s.miroshnichenko@yadro.com> wrote: > > Reading an empty slot returns all ones, which triggers a false > EEH error event on PowerNV. This patch unfreezes the bus where > it has happened. > > Signed-off-by: Sergey Miroshnichenko <s.miroshnichenko@yadro.com> > --- > arch/powerpc/include/asm/ppc-pci.h | 1 + > arch/powerpc/kernel/pci_dn.c | 2 +- > arch/powerpc/platforms/powernv/pci.c | 31 +++++++++++++++++++++++++--- > 3 files changed, 30 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/include/asm/ppc-pci.h b/arch/powerpc/include/asm/ppc-pci.h > index f191ef0d2a0a..a22d52a9bb1f 100644 > --- a/arch/powerpc/include/asm/ppc-pci.h > +++ b/arch/powerpc/include/asm/ppc-pci.h > @@ -40,6 +40,7 @@ void *traverse_pci_dn(struct pci_dn *root, > void *(*fn)(struct pci_dn *, void *), > void *data); > extern void pci_devs_phb_init_dynamic(struct pci_controller *phb); > +struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus); > > /* From rtas_pci.h */ > extern void init_pci_config_tokens (void); > diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c > index ab147a1909c8..341ed71250f1 100644 > --- a/arch/powerpc/kernel/pci_dn.c > +++ b/arch/powerpc/kernel/pci_dn.c > @@ -40,7 +40,7 @@ > * one of PF's bridge. For other devices, their firmware > * data is linked to that of their bridge. > */ > -static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus) > +struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus) > { > struct pci_bus *pbus; > struct device_node *dn; > diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c > index 41a381dfc2a1..8cc6661781e2 100644 > --- a/arch/powerpc/platforms/powernv/pci.c > +++ b/arch/powerpc/platforms/powernv/pci.c > @@ -761,6 +761,21 @@ static inline pnv_pci_cfg_check(struct pci_dn *pdn) > } > #endif /* CONFIG_EEH */ > > +static int get_bus_pe_number(struct pci_bus *bus) > +{ > + struct pci_dn *pdn = pci_bus_to_pdn(bus); > + struct pci_dn *child; > + > + if (!pdn) > + return IODA_INVALID_PE; > + > + list_for_each_entry(child, &pdn->child_list, list) > + if (child->pe_number != IODA_INVALID_PE) > + return child->pe_number; > + > + return IODA_INVALID_PE; > +} > + > static int pnv_pci_read_config(struct pci_bus *bus, > unsigned int devfn, > int where, int size, u32 *val) > @@ -772,9 +787,19 @@ static int pnv_pci_read_config(struct pci_bus *bus, > > *val = 0xFFFFFFFF; > pdn = pci_get_pdn_by_devfn(bus, devfn); > - if (!pdn) > - return pnv_pci_cfg_read_raw(phb->opal_id, bus->number, devfn, > - where, size, val); > + if (!pdn) { > + int pe_number = get_bus_pe_number(bus); > + > + ret = pnv_pci_cfg_read_raw(phb->opal_id, bus->number, devfn, > + where, size, val); > + > + if (!ret && (*val == EEH_IO_ERROR_VALUE(size)) && phb->unfreeze_pe) > + phb->unfreeze_pe(phb, (pe_number == IODA_INVALID_PE) ? > + phb->ioda.reserved_pe_idx : pe_number, > + OPAL_EEH_ACTION_CLEAR_FREEZE_ALL); > + > + return ret; > + } > > if (!pnv_pci_cfg_check(pdn)) > return PCIBIOS_DEVICE_NOT_FOUND; > -- > 2.20.1 > Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
diff --git a/arch/powerpc/include/asm/ppc-pci.h b/arch/powerpc/include/asm/ppc-pci.h index f191ef0d2a0a..a22d52a9bb1f 100644 --- a/arch/powerpc/include/asm/ppc-pci.h +++ b/arch/powerpc/include/asm/ppc-pci.h @@ -40,6 +40,7 @@ void *traverse_pci_dn(struct pci_dn *root, void *(*fn)(struct pci_dn *, void *), void *data); extern void pci_devs_phb_init_dynamic(struct pci_controller *phb); +struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus); /* From rtas_pci.h */ extern void init_pci_config_tokens (void); diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c index ab147a1909c8..341ed71250f1 100644 --- a/arch/powerpc/kernel/pci_dn.c +++ b/arch/powerpc/kernel/pci_dn.c @@ -40,7 +40,7 @@ * one of PF's bridge. For other devices, their firmware * data is linked to that of their bridge. */ -static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus) +struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus) { struct pci_bus *pbus; struct device_node *dn; diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c index 41a381dfc2a1..8cc6661781e2 100644 --- a/arch/powerpc/platforms/powernv/pci.c +++ b/arch/powerpc/platforms/powernv/pci.c @@ -761,6 +761,21 @@ static inline pnv_pci_cfg_check(struct pci_dn *pdn) } #endif /* CONFIG_EEH */ +static int get_bus_pe_number(struct pci_bus *bus) +{ + struct pci_dn *pdn = pci_bus_to_pdn(bus); + struct pci_dn *child; + + if (!pdn) + return IODA_INVALID_PE; + + list_for_each_entry(child, &pdn->child_list, list) + if (child->pe_number != IODA_INVALID_PE) + return child->pe_number; + + return IODA_INVALID_PE; +} + static int pnv_pci_read_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) @@ -772,9 +787,19 @@ static int pnv_pci_read_config(struct pci_bus *bus, *val = 0xFFFFFFFF; pdn = pci_get_pdn_by_devfn(bus, devfn); - if (!pdn) - return pnv_pci_cfg_read_raw(phb->opal_id, bus->number, devfn, - where, size, val); + if (!pdn) { + int pe_number = get_bus_pe_number(bus); + + ret = pnv_pci_cfg_read_raw(phb->opal_id, bus->number, devfn, + where, size, val); + + if (!ret && (*val == EEH_IO_ERROR_VALUE(size)) && phb->unfreeze_pe) + phb->unfreeze_pe(phb, (pe_number == IODA_INVALID_PE) ? + phb->ioda.reserved_pe_idx : pe_number, + OPAL_EEH_ACTION_CLEAR_FREEZE_ALL); + + return ret; + } if (!pnv_pci_cfg_check(pdn)) return PCIBIOS_DEVICE_NOT_FOUND;
Reading an empty slot returns all ones, which triggers a false EEH error event on PowerNV. This patch unfreezes the bus where it has happened. Signed-off-by: Sergey Miroshnichenko <s.miroshnichenko@yadro.com> --- arch/powerpc/include/asm/ppc-pci.h | 1 + arch/powerpc/kernel/pci_dn.c | 2 +- arch/powerpc/platforms/powernv/pci.c | 31 +++++++++++++++++++++++++--- 3 files changed, 30 insertions(+), 4 deletions(-)