diff options
Diffstat (limited to 'drivers/pci/pcie/aer/aerdrv_core.c')
| -rw-r--r-- | drivers/pci/pcie/aer/aerdrv_core.c | 757 |
1 files changed, 757 insertions, 0 deletions
diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c new file mode 100644 index 0000000000000..5591043acea73 --- /dev/null +++ b/drivers/pci/pcie/aer/aerdrv_core.c @@ -0,0 +1,757 @@ +/* + * drivers/pci/pcie/aer/aerdrv_core.c + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * This file implements the core part of PCI-Express AER. When an pci-express + * error is delivered, an error message will be collected and printed to + * console, then, an error recovery procedure will be executed by following + * the pci error recovery rules. + * + * Copyright (C) 2006 Intel Corp. + * Tom Long Nguyen (tom.l.nguyen@intel.com) + * Zhang Yanmin (yanmin.zhang@intel.com) + * + */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/pm.h> +#include <linux/suspend.h> +#include <linux/acpi.h> +#include <linux/pci-acpi.h> +#include <linux/delay.h> +#include "aerdrv.h" + +static int forceload; +module_param(forceload, bool, 0); + +#define PCI_CFG_SPACE_SIZE (0x100) +int pci_find_aer_capability(struct pci_dev *dev) +{ + int pos; + u32 reg32 = 0; + + /* Check if it's a pci-express device */ + pos = pci_find_capability(dev, PCI_CAP_ID_EXP); + if (!pos) + return 0; + + /* Check if it supports pci-express AER */ + pos = PCI_CFG_SPACE_SIZE; + while (pos) { + if (pci_read_config_dword(dev, pos, ®32)) + return 0; + + /* some broken boards return ~0 */ + if (reg32 == 0xffffffff) + return 0; + + if (PCI_EXT_CAP_ID(reg32) == PCI_EXT_CAP_ID_ERR) + break; + + pos = reg32 >> 20; + } + + return pos; +} + +int pci_enable_pcie_error_reporting(struct pci_dev *dev) +{ + u16 reg16 = 0; + int pos; + + pos = pci_find_capability(dev, PCI_CAP_ID_EXP); + if (!pos) + return -EIO; + + pci_read_config_word(dev, pos+PCI_EXP_DEVCTL, ®16); + reg16 = reg16 | + PCI_EXP_DEVCTL_CERE | + PCI_EXP_DEVCTL_NFERE | + PCI_EXP_DEVCTL_FERE | + PCI_EXP_DEVCTL_URRE; + pci_write_config_word(dev, pos+PCI_EXP_DEVCTL, + reg16); + return 0; +} + +int pci_disable_pcie_error_reporting(struct pci_dev *dev) +{ + u16 reg16 = 0; + int pos; + + pos = pci_find_capability(dev, PCI_CAP_ID_EXP); + if (!pos) + return -EIO; + + pci_read_config_word(dev, pos+PCI_EXP_DEVCTL, ®16); + reg16 = reg16 & ~(PCI_EXP_DEVCTL_CERE | + PCI_EXP_DEVCTL_NFERE | + PCI_EXP_DEVCTL_FERE | + PCI_EXP_DEVCTL_URRE); + pci_write_config_word(dev, pos+PCI_EXP_DEVCTL, + reg16); + return 0; +} + +int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev) +{ + int pos; + u32 status, mask; + + pos = pci_find_aer_capability(dev); + if (!pos) + return -EIO; + + pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status); + pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &mask); + if (dev->error_state == pci_channel_io_normal) + status &= ~mask; /* Clear corresponding nonfatal bits */ + else + status &= mask; /* Clear corresponding fatal bits */ + pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status); + + return 0; +} + +static int find_device_iter(struct device *device, void *data) +{ + struct pci_dev *dev; + u16 id = *(unsigned long *)data; + u8 secondary, subordinate, d_bus = id >> 8; + + if (device->bus == &pci_bus_type) { + dev = to_pci_dev(device); + if (id == ((dev->bus->number << 8) | dev->devfn)) { + /* + * Device ID match + */ + *(unsigned long*)data = (unsigned long)device; + return 1; + } + + /* + * If device is P2P, check if it is an upstream? + */ + if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) { + pci_read_config_byte(dev, PCI_SECONDARY_BUS, + &secondary); + pci_read_config_byte(dev, PCI_SUBORDINATE_BUS, + &subordinate); + if (d_bus >= secondary && d_bus <= subordinate) { + *(unsigned long*)data = (unsigned long)device; + return 1; + } + } + } + + return 0; +} + +/** + * find_source_device - search through device hierarchy for source device + * @p_dev: pointer to Root Port pci_dev data structure + * @id: device ID of agent who sends an error message to this Root Port + * + * Invoked when error is detected at the Root Port. + **/ +static struct device* find_source_device(struct pci_dev *parent, u16 id) +{ + struct pci_dev *dev = parent; + struct device *device; + unsigned long device_addr; + int status; + + /* Is Root Port an agent that sends error message? */ + if (id == ((dev->bus->number << 8) | dev->devfn)) + return &dev->dev; + + do { + device_addr = id; + if ((status = device_for_each_child(&dev->dev, + &device_addr, find_device_iter))) { + device = (struct device*)device_addr; + dev = to_pci_dev(device); + if (id == ((dev->bus->number << 8) | dev->devfn)) + return device; + } + }while (status); + + return NULL; +} + +static void report_error_detected(struct pci_dev *dev, void *data) +{ + pci_ers_result_t vote; + struct pci_error_handlers *err_handler; + struct aer_broadcast_data *result_data; + result_data = (struct aer_broadcast_data *) data; + + dev->error_state = result_data->state; + + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->error_detected) { + if (result_data->state == pci_channel_io_frozen && + !(dev->hdr_type & PCI_HEADER_TYPE_BRIDGE)) { + /* + * In case of fatal recovery, if one of down- + * stream device has no driver. We might be + * unable to recover because a later insmod + * of a driver for this device is unaware of + * its hw state. + */ + printk(KERN_DEBUG "Device ID[%s] has %s\n", + dev->dev.bus_id, (dev->driver) ? + "no AER-aware driver" : "no driver"); + } + return; + } + + err_handler = dev->driver->err_handler; + vote = err_handler->error_detected(dev, result_data->state); + result_data->result = merge_result(result_data->result, vote); + return; +} + +static void report_mmio_enabled(struct pci_dev *dev, void *data) +{ + pci_ers_result_t vote; + struct pci_error_handlers *err_handler; + struct aer_broadcast_data *result_data; + result_data = (struct aer_broadcast_data *) data; + + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->mmio_enabled) + return; + + err_handler = dev->driver->err_handler; + vote = err_handler->mmio_enabled(dev); + result_data->result = merge_result(result_data->result, vote); + return; +} + +static void report_slot_reset(struct pci_dev *dev, void *data) +{ + pci_ers_result_t vote; + struct pci_error_handlers *err_handler; + struct aer_broadcast_data *result_data; + result_data = (struct aer_broadcast_data *) data; + + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->slot_reset) + return; + + err_handler = dev->driver->err_handler; + vote = err_handler->slot_reset(dev); + result_data->result = merge_result(result_data->result, vote); + return; +} + +static void report_resume(struct pci_dev *dev, void *data) +{ + struct pci_error_handlers *err_handler; + + dev->error_state = pci_channel_io_normal; + + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->slot_reset) + return; + + err_handler = dev->driver->err_handler; + err_handler->resume(dev); + return; +} + +/** + * broadcast_error_message - handle message broadcast to downstream drivers + * @device: pointer to from where in a hierarchy message is broadcasted down + * @api: callback to be broadcasted + * @state: error state + * + * Invoked during error recovery process. Once being invoked, the content + * of error severity will be broadcasted to all downstream drivers in a + * hierarchy in question. + **/ +static pci_ers_result_t broadcast_error_message(struct pci_dev *dev, + enum pci_channel_state state, + char *error_mesg, + void (*cb)(struct pci_dev *, void *)) +{ + struct aer_broadcast_data result_data; + + printk(KERN_DEBUG "Broadcast %s message\n", error_mesg); + result_data.state = state; + if (cb == report_error_detected) + result_data.result = PCI_ERS_RESULT_CAN_RECOVER; + else + result_data.result = PCI_ERS_RESULT_RECOVERED; + + if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) { + /* + * If the error is reported by a bridge, we think this error + * is related to the downstream link of the bridge, so we + * do error recovery on all subordinates of the bridge instead + * of the bridge and clear the error status of the bridge. + */ + if (cb == report_error_detected) + dev->error_state = state; + pci_walk_bus(dev->subordinate, cb, &result_data); + if (cb == report_resume) { + pci_cleanup_aer_uncorrect_error_status(dev); + dev->error_state = pci_channel_io_normal; + } + } + else { + /* + * If the error is reported by an end point, we think this + * error is related to the upstream link of the end point. + */ + pci_walk_bus(dev->bus, cb, &result_data); + } + + return result_data.result; +} + +struct find_aer_service_data { + struct pcie_port_service_driver *aer_driver; + int is_downstream; +}; + +static int find_aer_service_iter(struct device *device, void *data) +{ + struct device_driver *driver; + struct pcie_port_service_driver *service_driver; + struct pcie_device *pcie_dev; + struct find_aer_service_data *result; + + result = (struct find_aer_service_data *) data; + + if (device->bus == &pcie_port_bus_type) { + pcie_dev = to_pcie_device(device); + if (pcie_dev->id.port_type == PCIE_SW_DOWNSTREAM_PORT) + result->is_downstream = 1; + + driver = device->driver; + if (driver) { + service_driver = to_service_driver(driver); + if (service_driver->id_table->service_type == + PCIE_PORT_SERVICE_AER) { + result->aer_driver = service_driver; + return 1; + } + } + } + + return 0; +} + +static void find_aer_service(struct pci_dev *dev, + struct find_aer_service_data *data) +{ + device_for_each_child(&dev->dev, data, find_aer_service_iter); +} + +static pci_ers_result_t reset_link(struct pcie_device *aerdev, + struct pci_dev *dev) +{ + struct pci_dev *udev; + pci_ers_result_t status; + struct find_aer_service_data data; + + if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) + udev = dev; + else + udev= dev->bus->self; + + data.is_downstream = 0; + data.aer_driver = NULL; + find_aer_service(udev, &data); + + /* + * Use the aer driver of the error agent firstly. + * If it hasn't the aer driver, use the root port's + */ + if (!data.aer_driver || !data.aer_driver->reset_link) { + if (data.is_downstream && + aerdev->device.driver && + to_service_driver(aerdev->device.driver)->reset_link) { + data.aer_driver = + to_service_driver(aerdev->device.driver); + } else { + printk(KERN_DEBUG "No link-reset support to Device ID" + "[%s]\n", + dev->dev.bus_id); + return PCI_ERS_RESULT_DISCONNECT; + } + } + + status = data.aer_driver->reset_link(udev); + if (status != PCI_ERS_RESULT_RECOVERED) { + printk(KERN_DEBUG "Link reset at upstream Device ID" + "[%s] failed\n", + udev->dev.bus_id); + return PCI_ERS_RESULT_DISCONNECT; + } + + return status; +} + +/** + * do_recovery - handle nonfatal/fatal error recovery process + * @aerdev: pointer to a pcie_device data structure of root port + * @dev: pointer to a pci_dev data structure of agent detecting an error + * @severity: error severity type + * + * Invoked when an error is nonfatal/fatal. Once being invoked, broadcast + * error detected message to all downstream drivers within a hierarchy in + * question and return the returned code. + **/ +static pci_ers_result_t do_recovery(struct pcie_device *aerdev, + struct pci_dev *dev, + int severity) +{ + pci_ers_result_t status, result = PCI_ERS_RESULT_RECOVERED; + enum pci_channel_state state; + + if (severity == AER_FATAL) + state = pci_channel_io_frozen; + else + state = pci_channel_io_normal; + + status = broadcast_error_message(dev, + state, + "error_detected", + report_error_detected); + + if (severity == AER_FATAL) { + result = reset_link(aerdev, dev); + if (result != PCI_ERS_RESULT_RECOVERED) { + /* TODO: Should panic here? */ + return result; + } + } + + if (status == PCI_ERS_RESULT_CAN_RECOVER) + status = broadcast_error_message(dev, + state, + "mmio_enabled", + report_mmio_enabled); + + if (status == PCI_ERS_RESULT_NEED_RESET) { + /* + * TODO: Should call platform-specific + * functions to reset slot before calling + * drivers' slot_reset callbacks? + */ + status = broadcast_error_message(dev, + state, + "slot_reset", + report_slot_reset); + } + + if (status == PCI_ERS_RESULT_RECOVERED) + broadcast_error_message(dev, + state, + "resume", + report_resume); + + return status; +} + +/** + * handle_error_source - handle logging error into an event log + * @aerdev: pointer to pcie_device data structure of the root port + * @dev: pointer to pci_dev data structure of error source device + * @info: comprehensive error information + * + * Invoked when an error being detected by Root Port. + **/ +static void handle_error_source(struct pcie_device * aerdev, + struct pci_dev *dev, + struct aer_err_info info) +{ + pci_ers_result_t status = 0; + int pos; + + if (info.severity == AER_CORRECTABLE) { + /* + * Correctable error does not need software intevention. + * No need to go through error recovery process. + */ + pos = pci_find_aer_capability(dev); + if (pos) + pci_write_config_dword(dev, pos + PCI_ERR_COR_STATUS, + info.status); + } else { + status = do_recovery(aerdev, dev, info.severity); + if (status == PCI_ERS_RESULT_RECOVERED) { + printk(KERN_DEBUG "AER driver successfully recovered\n"); + } else { + /* TODO: Should kernel panic here? */ + printk(KERN_DEBUG "AER driver didn't recover\n"); + } + } +} + +/** + * aer_enable_rootport - enable Root Port's interrupts when receiving messages + * @rpc: pointer to a Root Port data structure + * + * Invoked when PCIE bus loads AER service driver. + **/ +void aer_enable_rootport(struct aer_rpc *rpc) +{ + struct pci_dev *pdev = rpc->rpd->port; + int pos, aer_pos; + u16 reg16; + u32 reg32; + + pos = pci_find_capability(pdev, PCI_CAP_ID_EXP); + /* Clear PCIE Capability's Device Status */ + pci_read_config_word(pdev, pos+PCI_EXP_DEVSTA, ®16); + pci_write_config_word(pdev, pos+PCI_EXP_DEVSTA, reg16); + + /* Disable system error generation in response to error messages */ + pci_read_config_word(pdev, pos + PCI_EXP_RTCTL, ®16); + reg16 &= ~(SYSTEM_ERROR_INTR_ON_MESG_MASK); + pci_write_config_word(pdev, pos + PCI_EXP_RTCTL, reg16); + + aer_pos = pci_find_aer_capability(pdev); + /* Clear error status */ + pci_read_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, ®32); + pci_write_config_dword(pdev, aer_pos + PCI_ERR_ROOT_STATUS, reg32); + pci_read_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, ®32); + pci_write_config_dword(pdev, aer_pos + PCI_ERR_COR_STATUS, reg32); + pci_read_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, ®32); + pci_write_config_dword(pdev, aer_pos + PCI_ERR_UNCOR_STATUS, reg32); + + /* Enable Root Port device reporting error itself */ + pci_read_config_word(pdev, pos+PCI_EXP_DEVCTL, ®16); + reg16 = reg16 | + PCI_EXP_DEVCTL_CERE | + PCI_EXP_DEVCTL_NFERE | + PCI_EXP_DEVCTL_FERE | + PCI_EXP_DEVCTL_URRE; + pci_write_config_word(pdev, pos+PCI_EXP_DEVCTL, + reg16); + + /* Enable Root Port's interrupt in response to error messages */ + pci_write_config_dword(pdev, + aer_pos + PCI_ERR_ROOT_COMMAND, + ROOT_PORT_INTR_ON_MESG_MASK); +} + +/** + * disable_root_aer - disable Root Port's interrupts when receiving messages + * @rpc: pointer to a Root Port data structure + * + * Invoked when PCIE bus unloads AER service driver. + **/ +static void disable_root_aer(struct aer_rpc *rpc) +{ + struct pci_dev *pdev = rpc->rpd->port; + u32 reg32; + int pos; + + pos = pci_find_aer_capability(pdev); + /* Disable Root's interrupt in response to error messages */ + pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, 0); + + /* Clear Root's error status reg */ + pci_read_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, ®32); + pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_STATUS, reg32); +} + +/** + * get_e_source - retrieve an error source + * @rpc: pointer to the root port which holds an error + * + * Invoked by DPC handler to consume an error. + **/ +static struct aer_err_source* get_e_source(struct aer_rpc *rpc) +{ + struct aer_err_source *e_source; + unsigned long flags; + + /* Lock access to Root error producer/consumer index */ + spin_lock_irqsave(&rpc->e_lock, flags); + if (rpc->prod_idx == rpc->cons_idx) { + spin_unlock_irqrestore(&rpc->e_lock, flags); + return NULL; + } + e_source = &rpc->e_sources[rpc->cons_idx]; + rpc->cons_idx++; + if (rpc->cons_idx == AER_ERROR_SOURCES_MAX) + rpc->cons_idx = 0; + spin_unlock_irqrestore(&rpc->e_lock, flags); + + return e_source; +} + +static int get_device_error_info(struct pci_dev *dev, struct aer_err_info *info) +{ + int pos; + + pos = pci_find_aer_capability(dev); + + /* The device might not support AER */ + if (!pos) + return AER_SUCCESS; + + if (info->severity == AER_CORRECTABLE) { + pci_read_config_dword(dev, pos + PCI_ERR_COR_STATUS, + &info->status); + if (!(info->status & ERR_CORRECTABLE_ERROR_MASK)) + return AER_UNSUCCESS; + } else if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE || + info->severity == AER_NONFATAL) { + + /* Link is still healthy for IO reads */ + pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, + &info->status); + if (!(info->status & ERR_UNCORRECTABLE_ERROR_MASK)) + return AER_UNSUCCESS; + + if (info->status & AER_LOG_TLP_MASKS) { + info->flags |= AER_TLP_HEADER_VALID_FLAG; + pci_read_config_dword(dev, + pos + PCI_ERR_HEADER_LOG, &info->tlp.dw0); + pci_read_config_dword(dev, + pos + PCI_ERR_HEADER_LOG + 4, &info->tlp.dw1); + pci_read_config_dword(dev, + pos + PCI_ERR_HEADER_LOG + 8, &info->tlp.dw2); + pci_read_config_dword(dev, + pos + PCI_ERR_HEADER_LOG + 12, &info->tlp.dw3); + } + } + + return AER_SUCCESS; +} + +/** + * aer_isr_one_error - consume an error detected by root port + * @p_device: pointer to error root port service device + * @e_src: pointer to an error source + **/ +static void aer_isr_one_error(struct pcie_device *p_device, + struct aer_err_source *e_src) +{ + struct device *s_device; + struct aer_err_info e_info = {0, 0, 0,}; + int i; + u16 id; + + /* + * There is a possibility that both correctable error and + * uncorrectable error being logged. Report correctable error first. + */ + for (i = 1; i & ROOT_ERR_STATUS_MASKS ; i <<= 2) { + if (i > 4) + break; + if (!(e_src->status & i)) + continue; + + /* Init comprehensive error information */ + if (i & PCI_ERR_ROOT_COR_RCV) { + id = ERR_COR_ID(e_src->id); + e_info.severity = AER_CORRECTABLE; + } else { + id = ERR_UNCOR_ID(e_src->id); + e_info.severity = ((e_src->status >> 6) & 1); + } + if (e_src->status & + (PCI_ERR_ROOT_MULTI_COR_RCV | + PCI_ERR_ROOT_MULTI_UNCOR_RCV)) + e_info.flags |= AER_MULTI_ERROR_VALID_FLAG; + if (!(s_device = find_source_device(p_device->port, id))) { + printk(KERN_DEBUG "%s->can't find device of ID%04x\n", + __FUNCTION__, id); + continue; + } + if (get_device_error_info(to_pci_dev(s_device), &e_info) == + AER_SUCCESS) { + aer_print_error(to_pci_dev(s_device), &e_info); + handle_error_source(p_device, + to_pci_dev(s_device), + e_info); + } + } +} + +/** + * aer_isr - consume errors detected by root port + * @context: pointer to a private data of pcie device + * + * Invoked, as DPC, when root port records new detected error + **/ +void aer_isr(void *context) +{ + struct pcie_device *p_device = (struct pcie_device *) context; + struct aer_rpc *rpc = get_service_data(p_device); + struct aer_err_source *e_src; + + mutex_lock(&rpc->rpc_mutex); + e_src = get_e_source(rpc); + while (e_src) { + aer_isr_one_error(p_device, e_src); + e_src = get_e_source(rpc); + } + mutex_unlock(&rpc->rpc_mutex); + + wake_up(&rpc->wait_release); +} + +/** + * aer_delete_rootport - disable root port aer and delete service data + * @rpc: pointer to a root port device being deleted + * + * Invoked when AER service unloaded on a specific Root Port + **/ +void aer_delete_rootport(struct aer_rpc *rpc) +{ + /* Disable root port AER itself */ + disable_root_aer(rpc); + + kfree(rpc); +} + +/** + * aer_init - provide AER initialization + * @dev: pointer to AER pcie device + * + * Invoked when AER service driver is loaded. + **/ +int aer_init(struct pcie_device *dev) +{ + int status; + + /* Run _OSC Method */ + status = aer_osc_setup(dev->port); + + if(status != OSC_METHOD_RUN_SUCCESS) { + printk(KERN_DEBUG "%s: AER service init fails - %s\n", + __FUNCTION__, + (status == OSC_METHOD_NOT_SUPPORTED) ? + "No ACPI _OSC support" : "Run ACPI _OSC fails"); + + if (!forceload) + return status; + } + + return AER_SUCCESS; +} + +EXPORT_SYMBOL_GPL(pci_find_aer_capability); +EXPORT_SYMBOL_GPL(pci_enable_pcie_error_reporting); +EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting); +EXPORT_SYMBOL_GPL(pci_cleanup_aer_uncorrect_error_status); + |