diff options
Diffstat (limited to 'drivers/pci/hotplug/rpaphp_pci.c')
| -rw-r--r-- | drivers/pci/hotplug/rpaphp_pci.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/rpaphp_pci.c b/drivers/pci/hotplug/rpaphp_pci.c new file mode 100644 index 000000000..bcfd26ec6 --- /dev/null +++ b/drivers/pci/hotplug/rpaphp_pci.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * PCI Hot Plug Controller Driver for RPA-compliant PPC64 platform. + * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com> + * + * All rights reserved. + * + * Send feedback to <lxie@us.ibm.com> + * + */ +#include <linux/of.h> +#include <linux/pci.h> +#include <linux/string.h> + +#include <asm/pci-bridge.h> +#include <asm/rtas.h> +#include <asm/machdep.h> + +#include "../pci.h" /* for pci_add_new_bus */ +#include "rpaphp.h" + +/* + * RTAS call get-sensor-state(DR_ENTITY_SENSE) return values as per PAPR: + * -- generic return codes --- + * -1: Hardware Error + * -2: RTAS_BUSY + * -3: Invalid sensor. RTAS Parameter Error. + * -- rtas_get_sensor function specific return codes --- + * -9000: Need DR entity to be powered up and unisolated before RTAS call + * -9001: Need DR entity to be powered up, but not unisolated, before RTAS call + * -9002: DR entity unusable + * 990x: Extended delay - where x is a number in the range of 0-5 + */ +#define RTAS_SLOT_UNISOLATED -9000 +#define RTAS_SLOT_NOT_UNISOLATED -9001 +#define RTAS_SLOT_NOT_USABLE -9002 + +static int rtas_get_sensor_errno(int rtas_rc) +{ + switch (rtas_rc) { + case 0: + /* Success case */ + return 0; + case RTAS_SLOT_UNISOLATED: + case RTAS_SLOT_NOT_UNISOLATED: + return -EFAULT; + case RTAS_SLOT_NOT_USABLE: + return -ENODEV; + case RTAS_BUSY: + case RTAS_EXTENDED_DELAY_MIN...RTAS_EXTENDED_DELAY_MAX: + return -EBUSY; + default: + return rtas_error_rc(rtas_rc); + } +} + +/* + * get_adapter_status() can be called by the EEH handler during EEH recovery. + * On certain PHB failures, the RTAS call rtas_call(get-sensor-state) returns + * extended busy error (9902) until PHB is recovered by pHyp. The RTAS call + * interface rtas_get_sensor() loops over the RTAS call on extended delay + * return code (9902) until the return value is either success (0) or error + * (-1). This causes the EEH handler to get stuck for ~6 seconds before it + * could notify that the PCI error has been detected and stop any active + * operations. This sometimes causes EEH recovery to fail. To avoid this issue, + * invoke rtas_call(get-sensor-state) directly if the respective PE is in EEH + * recovery state and return -EBUSY error based on RTAS return status. This + * will help the EEH handler to notify the driver about the PCI error + * immediately and successfully proceed with EEH recovery steps. + */ + +static int __rpaphp_get_sensor_state(struct slot *slot, int *state) +{ + int rc; + int token = rtas_token("get-sensor-state"); + struct pci_dn *pdn; + struct eeh_pe *pe; + struct pci_controller *phb = PCI_DN(slot->dn)->phb; + + if (token == RTAS_UNKNOWN_SERVICE) + return -ENOENT; + + /* + * Fallback to existing method for empty slot or PE isn't in EEH + * recovery. + */ + pdn = list_first_entry_or_null(&PCI_DN(phb->dn)->child_list, + struct pci_dn, list); + if (!pdn) + goto fallback; + + pe = eeh_dev_to_pe(pdn->edev); + if (pe && (pe->state & EEH_PE_RECOVERING)) { + rc = rtas_call(token, 2, 2, state, DR_ENTITY_SENSE, + slot->index); + return rtas_get_sensor_errno(rc); + } +fallback: + return rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state); +} + +int rpaphp_get_sensor_state(struct slot *slot, int *state) +{ + int rc; + int setlevel; + + rc = __rpaphp_get_sensor_state(slot, state); + + if (rc < 0) { + if (rc == -EFAULT || rc == -EEXIST) { + dbg("%s: slot must be power up to get sensor-state\n", + __func__); + + /* some slots have to be powered up + * before get-sensor will succeed. + */ + rc = rtas_set_power_level(slot->power_domain, POWER_ON, + &setlevel); + if (rc < 0) { + dbg("%s: power on slot[%s] failed rc=%d.\n", + __func__, slot->name, rc); + } else { + rc = __rpaphp_get_sensor_state(slot, state); + } + } else if (rc == -ENODEV) + info("%s: slot is unusable\n", __func__); + else + err("%s failed to get sensor state\n", __func__); + } + return rc; +} + +/** + * rpaphp_enable_slot - record slot state, config pci device + * @slot: target &slot + * + * Initialize values in the slot structure to indicate if there is a pci card + * plugged into the slot. If the slot is not empty, run the pcibios routine + * to get pcibios stuff correctly set up. + */ +int rpaphp_enable_slot(struct slot *slot) +{ + int rc, level, state; + struct pci_bus *bus; + + slot->state = EMPTY; + + /* Find out if the power is turned on for the slot */ + rc = rtas_get_power_level(slot->power_domain, &level); + if (rc) + return rc; + + /* Figure out if there is an adapter in the slot */ + rc = rpaphp_get_sensor_state(slot, &state); + if (rc) + return rc; + + bus = pci_find_bus_by_node(slot->dn); + if (!bus) { + err("%s: no pci_bus for dn %pOF\n", __func__, slot->dn); + return -EINVAL; + } + + slot->bus = bus; + slot->pci_devs = &bus->devices; + + /* if there's an adapter in the slot, go add the pci devices */ + if (state == PRESENT) { + slot->state = NOT_CONFIGURED; + + /* non-empty slot has to have child */ + if (!slot->dn->child) { + err("%s: slot[%s]'s device_node doesn't have child for adapter\n", + __func__, slot->name); + return -EINVAL; + } + + if (list_empty(&bus->devices)) { + pseries_eeh_init_edev_recursive(PCI_DN(slot->dn)); + pci_hp_add_devices(bus); + } + + if (!list_empty(&bus->devices)) { + slot->state = CONFIGURED; + } + + if (rpaphp_debug) { + struct pci_dev *dev; + dbg("%s: pci_devs of slot[%pOF]\n", __func__, slot->dn); + list_for_each_entry(dev, &bus->devices, bus_list) + dbg("\t%s\n", pci_name(dev)); + } + } + + return 0; +} |