From a131bfc69bc868083a6c7f9b5dad1331902a3534 Mon Sep 17 00:00:00 2001 From: Oliver O'Halloran Date: Sat, 25 Jul 2020 18:12:31 +1000 Subject: powerpc/eeh: Move PE tree setup into the platform The EEH core has a concept of a "PE tree" to support PowerNV. The PE tree follows the PCI bus structures because a reset asserted on an upstream bridge will be propagated to the downstream bridges. On pseries there's a 1-1 correspondence between what the guest sees are a PHB and a PE so the "tree" is really just a single node. Current the EEH core is reponsible for setting up this PE tree which it does by traversing the pci_dn tree. The structure of the pci_dn tree matches the bus tree on PowerNV which leads to the PE tree being "correct" this setup method doesn't make a whole lot of sense and it's actively confusing for the pseries case where it doesn't really do anything. We want to remove the dependence on pci_dn anyway so this patch move choosing where to insert a new PE into the platform code rather than being part of the generic EEH code. For PowerNV this simplifies the tree building logic and removes the use of pci_dn. For pseries we keep the existing logic. I'm not really convinced it does anything due to the 1-1 PE-to-PHB correspondence so every device under that PHB should be in the same PE, but I'd rather not remove it entirely until we've had a chance to look at it more deeply. Signed-off-by: Oliver O'Halloran Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200725081231.39076-14-oohall@gmail.com --- arch/powerpc/include/asm/eeh.h | 2 +- arch/powerpc/kernel/eeh_pe.c | 71 ++++++++-------------------- arch/powerpc/platforms/powernv/eeh-powernv.c | 27 ++++++++++- arch/powerpc/platforms/pseries/eeh_pseries.c | 67 ++++++++++++++++++++++---- 4 files changed, 103 insertions(+), 64 deletions(-) diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index ee5f354bc8b9..d5f369bcd130 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -283,7 +283,7 @@ struct eeh_pe *eeh_phb_pe_get(struct pci_controller *phb); struct eeh_pe *eeh_pe_next(struct eeh_pe *pe, struct eeh_pe *root); struct eeh_pe *eeh_pe_get(struct pci_controller *phb, int pe_no, int config_addr); -int eeh_pe_tree_insert(struct eeh_dev *edev); +int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent); int eeh_pe_tree_remove(struct eeh_dev *edev); void eeh_pe_update_time_stamp(struct eeh_pe *pe); void *eeh_pe_traverse(struct eeh_pe *root, diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c index 898205829a8f..d2aaaa73fdd5 100644 --- a/arch/powerpc/kernel/eeh_pe.c +++ b/arch/powerpc/kernel/eeh_pe.c @@ -318,53 +318,20 @@ struct eeh_pe *eeh_pe_get(struct pci_controller *phb, return pe; } -/** - * eeh_pe_get_parent - Retrieve the parent PE - * @edev: EEH device - * - * The whole PEs existing in the system are organized as hierarchy - * tree. The function is used to retrieve the parent PE according - * to the parent EEH device. - */ -static struct eeh_pe *eeh_pe_get_parent(struct eeh_dev *edev) -{ - struct eeh_dev *parent; - struct pci_dn *pdn = eeh_dev_to_pdn(edev); - - /* - * It might have the case for the indirect parent - * EEH device already having associated PE, but - * the direct parent EEH device doesn't have yet. - */ - if (edev->physfn) - pdn = pci_get_pdn(edev->physfn); - else - pdn = pdn ? pdn->parent : NULL; - while (pdn) { - /* We're poking out of PCI territory */ - parent = pdn_to_eeh_dev(pdn); - if (!parent) - return NULL; - - if (parent->pe) - return parent->pe; - - pdn = pdn->parent; - } - - return NULL; -} - /** * eeh_pe_tree_insert - Add EEH device to parent PE * @edev: EEH device + * @new_pe_parent: PE to create additional PEs under * - * Add EEH device to the parent PE. If the parent PE already - * exists, the PE type will be changed to EEH_PE_BUS. Otherwise, - * we have to create new PE to hold the EEH device and the new - * PE will be linked to its parent PE as well. + * Add EEH device to the PE in edev->pe_config_addr. If a PE already + * exists with that address then @edev is added to that PE. Otherwise + * a new PE is created and inserted into the PE tree as a child of + * @new_pe_parent. + * + * If @new_pe_parent is NULL then the new PE will be inserted under + * directly under the the PHB. */ -int eeh_pe_tree_insert(struct eeh_dev *edev) +int eeh_pe_tree_insert(struct eeh_dev *edev, struct eeh_pe *new_pe_parent) { struct pci_controller *hose = edev->controller; struct eeh_pe *pe, *parent; @@ -398,8 +365,7 @@ int eeh_pe_tree_insert(struct eeh_dev *edev) parent = parent->parent; } - eeh_edev_dbg(edev, - "Added to device PE (parent: PE#%x)\n", + eeh_edev_dbg(edev, "Added to existing PE (parent: PE#%x)\n", pe->parent->addr); } else { /* Mark the PE as type of PCI bus */ @@ -431,10 +397,9 @@ int eeh_pe_tree_insert(struct eeh_dev *edev) * to PHB directly. Otherwise, we have to associate the * PE with its parent. */ - parent = eeh_pe_get_parent(edev); - if (!parent) { - parent = eeh_phb_pe_get(hose); - if (!parent) { + if (!new_pe_parent) { + new_pe_parent = eeh_phb_pe_get(hose); + if (!new_pe_parent) { pr_err("%s: No PHB PE is found (PHB Domain=%d)\n", __func__, hose->global_number); edev->pe = NULL; @@ -442,17 +407,19 @@ int eeh_pe_tree_insert(struct eeh_dev *edev) return -EEXIST; } } - pe->parent = parent; + + /* link new PE into the tree */ + pe->parent = new_pe_parent; + list_add_tail(&pe->child, &new_pe_parent->child_list); /* * Put the newly created PE into the child list and * link the EEH device accordingly. */ - list_add_tail(&pe->child, &parent->child_list); list_add_tail(&edev->entry, &pe->edevs); edev->pe = pe; - eeh_edev_dbg(edev, "Added to device PE (parent: PE#%x)\n", - pe->parent->addr); + eeh_edev_dbg(edev, "Added to new (parent: PE#%x)\n", + new_pe_parent->addr); return 0; } diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c index 8c9fca773692..9af8c3b98853 100644 --- a/arch/powerpc/platforms/powernv/eeh-powernv.c +++ b/arch/powerpc/platforms/powernv/eeh-powernv.c @@ -338,6 +338,28 @@ static int pnv_eeh_find_ecap(struct pci_dn *pdn, int cap) return 0; } +static struct eeh_pe *pnv_eeh_get_upstream_pe(struct pci_dev *pdev) +{ + struct pci_controller *hose = pdev->bus->sysdata; + struct pnv_phb *phb = hose->private_data; + struct pci_dev *parent = pdev->bus->self; + +#ifdef CONFIG_PCI_IOV + /* for VFs we use the PF's PE as the upstream PE */ + if (pdev->is_virtfn) + parent = pdev->physfn; +#endif + + /* otherwise use the PE of our parent bridge */ + if (parent) { + struct pnv_ioda_pe *ioda_pe = pnv_ioda_get_pe(parent); + + return eeh_pe_get(phb->hose, ioda_pe->pe_number, 0); + } + + return NULL; +} + /** * pnv_eeh_probe - Do probe on PCI device * @pdev: pci_dev to probe @@ -350,6 +372,7 @@ static struct eeh_dev *pnv_eeh_probe(struct pci_dev *pdev) struct pci_controller *hose = pdn->phb; struct pnv_phb *phb = hose->private_data; struct eeh_dev *edev = pdn_to_eeh_dev(pdn); + struct eeh_pe *upstream_pe; uint32_t pcie_flags; int ret; int config_addr = (pdn->busno << 8) | (pdn->devfn); @@ -398,8 +421,10 @@ static struct eeh_dev *pnv_eeh_probe(struct pci_dev *pdev) edev->pe_config_addr = phb->ioda.pe_rmap[config_addr]; + upstream_pe = pnv_eeh_get_upstream_pe(pdev); + /* Create PE */ - ret = eeh_pe_tree_insert(edev); + ret = eeh_pe_tree_insert(edev, upstream_pe); if (ret) { eeh_edev_warn(edev, "Failed to add device to PE (code %d)\n", ret); return NULL; diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/powerpc/platforms/pseries/eeh_pseries.c index 69650d8dc705..cb2d9a970b7b 100644 --- a/arch/powerpc/platforms/pseries/eeh_pseries.c +++ b/arch/powerpc/platforms/pseries/eeh_pseries.c @@ -69,11 +69,16 @@ void pseries_pcibios_bus_add_device(struct pci_dev *pdev) pseries_eeh_init_edev(pdn); #ifdef CONFIG_PCI_IOV if (pdev->is_virtfn) { + /* + * FIXME: This really should be handled by choosing the right + * parent PE in in pseries_eeh_init_edev(). + */ + struct eeh_pe *physfn_pe = pci_dev_to_eeh_dev(pdev->physfn)->pe; struct eeh_dev *edev = pdn_to_eeh_dev(pdn); edev->pe_config_addr = (pdn->busno << 16) | (pdn->devfn << 8); eeh_pe_tree_remove(edev); /* Remove as it is adding to bus pe */ - eeh_pe_tree_insert(edev); /* Add as VF PE type */ + eeh_pe_tree_insert(edev, physfn_pe); /* Add as VF PE type */ } #endif eeh_probe_device(pdev); @@ -385,6 +390,43 @@ static int pseries_eeh_find_ecap(struct pci_dn *pdn, int cap) return 0; } +/** + * pseries_eeh_pe_get_parent - Retrieve the parent PE + * @edev: EEH device + * + * The whole PEs existing in the system are organized as hierarchy + * tree. The function is used to retrieve the parent PE according + * to the parent EEH device. + */ +static struct eeh_pe *pseries_eeh_pe_get_parent(struct eeh_dev *edev) +{ + struct eeh_dev *parent; + struct pci_dn *pdn = eeh_dev_to_pdn(edev); + + /* + * It might have the case for the indirect parent + * EEH device already having associated PE, but + * the direct parent EEH device doesn't have yet. + */ + if (edev->physfn) + pdn = pci_get_pdn(edev->physfn); + else + pdn = pdn ? pdn->parent : NULL; + while (pdn) { + /* We're poking out of PCI territory */ + parent = pdn_to_eeh_dev(pdn); + if (!parent) + return NULL; + + if (parent->pe) + return parent->pe; + + pdn = pdn->parent; + } + + return NULL; +} + /** * pseries_eeh_init_edev - initialise the eeh_dev and eeh_pe for a pci_dn * @@ -468,6 +510,8 @@ void pseries_eeh_init_edev(struct pci_dn *pdn) if (ret) { eeh_edev_dbg(edev, "EEH failed to enable on device (code %d)\n", ret); } else { + struct eeh_pe *parent; + /* Retrieve PE address */ edev->pe_config_addr = pseries_eeh_get_pe_addr(pdn); pe.addr = edev->pe_config_addr; @@ -480,16 +524,19 @@ void pseries_eeh_init_edev(struct pci_dn *pdn) if (ret > 0 && ret != EEH_STATE_NOT_SUPPORT) enable = 1; - if (enable) { + /* + * This device doesn't support EEH, but it may have an + * EEH parent. In this case any error on the device will + * freeze the PE of it's upstream bridge, so added it to + * the upstream PE. + */ + parent = pseries_eeh_pe_get_parent(edev); + if (parent && !enable) + edev->pe_config_addr = parent->addr; + + if (enable || parent) { eeh_add_flag(EEH_ENABLED); - eeh_pe_tree_insert(edev); - } else if (pdn->parent && pdn_to_eeh_dev(pdn->parent) && - (pdn_to_eeh_dev(pdn->parent))->pe) { - /* This device doesn't support EEH, but it may have an - * EEH parent, in which case we mark it as supported. - */ - edev->pe_config_addr = pdn_to_eeh_dev(pdn->parent)->pe_config_addr; - eeh_pe_tree_insert(edev); + eeh_pe_tree_insert(edev, parent); } eeh_edev_dbg(edev, "EEH is %s on device (code %d)\n", (enable ? "enabled" : "unsupported"), ret); -- cgit v1.2.3