diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/pci/pcie/aer/aerdrv.c |
Initial import
Diffstat (limited to 'drivers/pci/pcie/aer/aerdrv.c')
-rw-r--r-- | drivers/pci/pcie/aer/aerdrv.c | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/drivers/pci/pcie/aer/aerdrv.c b/drivers/pci/pcie/aer/aerdrv.c new file mode 100644 index 000000000..0bf82a20a --- /dev/null +++ b/drivers/pci/pcie/aer/aerdrv.c @@ -0,0 +1,434 @@ +/* + * drivers/pci/pcie/aer/aerdrv.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 AER root port service driver. The driver will + * register an irq handler. When root port triggers an AER interrupt, the irq + * handler will collect root port status and schedule a work. + * + * 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/pci-acpi.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/pm.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/pcieport_if.h> +#include <linux/slab.h> + +#include "aerdrv.h" +#include "../../pci.h" + +/* + * Version Information + */ +#define DRIVER_VERSION "v1.0" +#define DRIVER_AUTHOR "tom.l.nguyen@intel.com" +#define DRIVER_DESC "Root Port Advanced Error Reporting Driver" +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +static int aer_probe(struct pcie_device *dev); +static void aer_remove(struct pcie_device *dev); +static pci_ers_result_t aer_error_detected(struct pci_dev *dev, + enum pci_channel_state error); +static void aer_error_resume(struct pci_dev *dev); +static pci_ers_result_t aer_root_reset(struct pci_dev *dev); + +static const struct pci_error_handlers aer_error_handlers = { + .error_detected = aer_error_detected, + .resume = aer_error_resume, +}; + +static struct pcie_port_service_driver aerdriver = { + .name = "aer", + .port_type = PCI_EXP_TYPE_ROOT_PORT, + .service = PCIE_PORT_SERVICE_AER, + + .probe = aer_probe, + .remove = aer_remove, + + .err_handler = &aer_error_handlers, + + .reset_link = aer_root_reset, +}; + +static int pcie_aer_disable; + +void pci_no_aer(void) +{ + pcie_aer_disable = 1; /* has priority over 'forceload' */ +} + +bool pci_aer_available(void) +{ + return !pcie_aer_disable && pci_msi_enabled(); +} + +static int set_device_error_reporting(struct pci_dev *dev, void *data) +{ + bool enable = *((bool *)data); + int type = pci_pcie_type(dev); + + if ((type == PCI_EXP_TYPE_ROOT_PORT) || + (type == PCI_EXP_TYPE_UPSTREAM) || + (type == PCI_EXP_TYPE_DOWNSTREAM)) { + if (enable) + pci_enable_pcie_error_reporting(dev); + else + pci_disable_pcie_error_reporting(dev); + } + + if (enable) + pcie_set_ecrc_checking(dev); + + return 0; +} + +/** + * set_downstream_devices_error_reporting - enable/disable the error reporting bits on the root port and its downstream ports. + * @dev: pointer to root port's pci_dev data structure + * @enable: true = enable error reporting, false = disable error reporting. + */ +static void set_downstream_devices_error_reporting(struct pci_dev *dev, + bool enable) +{ + set_device_error_reporting(dev, &enable); + + if (!dev->subordinate) + return; + pci_walk_bus(dev->subordinate, set_device_error_reporting, &enable); +} + +/** + * 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. + */ +static void aer_enable_rootport(struct aer_rpc *rpc) +{ + struct pci_dev *pdev = rpc->rpd->port; + int aer_pos; + u16 reg16; + u32 reg32; + + /* Clear PCIe Capability's Device Status */ + pcie_capability_read_word(pdev, PCI_EXP_DEVSTA, ®16); + pcie_capability_write_word(pdev, PCI_EXP_DEVSTA, reg16); + + /* Disable system error generation in response to error messages */ + pcie_capability_clear_word(pdev, PCI_EXP_RTCTL, + SYSTEM_ERROR_INTR_ON_MESG_MASK); + + aer_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR); + /* 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 error reporting for the root port device and downstream port + * devices. + */ + set_downstream_devices_error_reporting(pdev, true); + + /* Enable Root Port's interrupt in response to error messages */ + pci_read_config_dword(pdev, aer_pos + PCI_ERR_ROOT_COMMAND, ®32); + reg32 |= ROOT_PORT_INTR_ON_MESG_MASK; + pci_write_config_dword(pdev, aer_pos + PCI_ERR_ROOT_COMMAND, reg32); +} + +/** + * aer_disable_rootport - 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 aer_disable_rootport(struct aer_rpc *rpc) +{ + struct pci_dev *pdev = rpc->rpd->port; + u32 reg32; + int pos; + + /* + * Disable error reporting for the root port device and downstream port + * devices. + */ + set_downstream_devices_error_reporting(pdev, false); + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ERR); + /* Disable Root's interrupt in response to error messages */ + pci_read_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, ®32); + reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK; + pci_write_config_dword(pdev, pos + PCI_ERR_ROOT_COMMAND, reg32); + + /* 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); +} + +/** + * aer_irq - Root Port's ISR + * @irq: IRQ assigned to Root Port + * @context: pointer to Root Port data structure + * + * Invoked when Root Port detects AER messages. + */ +irqreturn_t aer_irq(int irq, void *context) +{ + unsigned int status, id; + struct pcie_device *pdev = (struct pcie_device *)context; + struct aer_rpc *rpc = get_service_data(pdev); + int next_prod_idx; + unsigned long flags; + int pos; + + pos = pci_find_ext_capability(pdev->port, PCI_EXT_CAP_ID_ERR); + /* + * Must lock access to Root Error Status Reg, Root Error ID Reg, + * and Root error producer/consumer index + */ + spin_lock_irqsave(&rpc->e_lock, flags); + + /* Read error status */ + pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, &status); + if (!(status & (PCI_ERR_ROOT_UNCOR_RCV|PCI_ERR_ROOT_COR_RCV))) { + spin_unlock_irqrestore(&rpc->e_lock, flags); + return IRQ_NONE; + } + + /* Read error source and clear error status */ + pci_read_config_dword(pdev->port, pos + PCI_ERR_ROOT_ERR_SRC, &id); + pci_write_config_dword(pdev->port, pos + PCI_ERR_ROOT_STATUS, status); + + /* Store error source for later DPC handler */ + next_prod_idx = rpc->prod_idx + 1; + if (next_prod_idx == AER_ERROR_SOURCES_MAX) + next_prod_idx = 0; + if (next_prod_idx == rpc->cons_idx) { + /* + * Error Storm Condition - possibly the same error occurred. + * Drop the error. + */ + spin_unlock_irqrestore(&rpc->e_lock, flags); + return IRQ_HANDLED; + } + rpc->e_sources[rpc->prod_idx].status = status; + rpc->e_sources[rpc->prod_idx].id = id; + rpc->prod_idx = next_prod_idx; + spin_unlock_irqrestore(&rpc->e_lock, flags); + + /* Invoke DPC handler */ + schedule_work(&rpc->dpc_handler); + + return IRQ_HANDLED; +} +EXPORT_SYMBOL_GPL(aer_irq); + +/** + * aer_alloc_rpc - allocate Root Port data structure + * @dev: pointer to the pcie_dev data structure + * + * Invoked when Root Port's AER service is loaded. + */ +static struct aer_rpc *aer_alloc_rpc(struct pcie_device *dev) +{ + struct aer_rpc *rpc; + + rpc = kzalloc(sizeof(struct aer_rpc), GFP_KERNEL); + if (!rpc) + return NULL; + + /* Initialize Root lock access, e_lock, to Root Error Status Reg */ + spin_lock_init(&rpc->e_lock); + + rpc->rpd = dev; + INIT_WORK(&rpc->dpc_handler, aer_isr); + mutex_init(&rpc->rpc_mutex); + init_waitqueue_head(&rpc->wait_release); + + /* Use PCIe bus function to store rpc into PCIe device */ + set_service_data(dev, rpc); + + return rpc; +} + +/** + * aer_remove - clean up resources + * @dev: pointer to the pcie_dev data structure + * + * Invoked when PCI Express bus unloads or AER probe fails. + */ +static void aer_remove(struct pcie_device *dev) +{ + struct aer_rpc *rpc = get_service_data(dev); + + if (rpc) { + /* If register interrupt service, it must be free. */ + if (rpc->isr) + free_irq(dev->irq, dev); + + wait_event(rpc->wait_release, rpc->prod_idx == rpc->cons_idx); + + aer_disable_rootport(rpc); + kfree(rpc); + set_service_data(dev, NULL); + } +} + +/** + * aer_probe - initialize resources + * @dev: pointer to the pcie_dev data structure + * @id: pointer to the service id data structure + * + * Invoked when PCI Express bus loads AER service driver. + */ +static int aer_probe(struct pcie_device *dev) +{ + int status; + struct aer_rpc *rpc; + struct device *device = &dev->device; + + /* Init */ + status = aer_init(dev); + if (status) + return status; + + /* Alloc rpc data structure */ + rpc = aer_alloc_rpc(dev); + if (!rpc) { + dev_printk(KERN_DEBUG, device, "alloc rpc failed\n"); + aer_remove(dev); + return -ENOMEM; + } + + /* Request IRQ ISR */ + status = request_irq(dev->irq, aer_irq, IRQF_SHARED, "aerdrv", dev); + if (status) { + dev_printk(KERN_DEBUG, device, "request IRQ failed\n"); + aer_remove(dev); + return status; + } + + rpc->isr = 1; + + aer_enable_rootport(rpc); + + return status; +} + +/** + * aer_root_reset - reset link on Root Port + * @dev: pointer to Root Port's pci_dev data structure + * + * Invoked by Port Bus driver when performing link reset at Root Port. + */ +static pci_ers_result_t aer_root_reset(struct pci_dev *dev) +{ + u32 reg32; + int pos; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR); + + /* Disable Root's interrupt in response to error messages */ + pci_read_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, ®32); + reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK; + pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32); + + pci_reset_bridge_secondary_bus(dev); + dev_printk(KERN_DEBUG, &dev->dev, "Root Port link has been reset\n"); + + /* Clear Root Error Status */ + pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, ®32); + pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, reg32); + + /* Enable Root Port's interrupt in response to error messages */ + pci_read_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, ®32); + reg32 |= ROOT_PORT_INTR_ON_MESG_MASK; + pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32); + + return PCI_ERS_RESULT_RECOVERED; +} + +/** + * aer_error_detected - update severity status + * @dev: pointer to Root Port's pci_dev data structure + * @error: error severity being notified by port bus + * + * Invoked by Port Bus driver during error recovery. + */ +static pci_ers_result_t aer_error_detected(struct pci_dev *dev, + enum pci_channel_state error) +{ + /* Root Port has no impact. Always recovers. */ + return PCI_ERS_RESULT_CAN_RECOVER; +} + +/** + * aer_error_resume - clean up corresponding error status bits + * @dev: pointer to Root Port's pci_dev data structure + * + * Invoked by Port Bus driver during nonfatal recovery. + */ +static void aer_error_resume(struct pci_dev *dev) +{ + int pos; + u32 status, mask; + u16 reg16; + + /* Clean up Root device status */ + pcie_capability_read_word(dev, PCI_EXP_DEVSTA, ®16); + pcie_capability_write_word(dev, PCI_EXP_DEVSTA, reg16); + + /* Clean AER Root Error Status */ + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR); + 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); +} + +/** + * aer_service_init - register AER root service driver + * + * Invoked when AER root service driver is loaded. + */ +static int __init aer_service_init(void) +{ + if (!pci_aer_available() || aer_acpi_firmware_first()) + return -ENXIO; + return pcie_port_service_register(&aerdriver); +} + +/** + * aer_service_exit - unregister AER root service driver + * + * Invoked when AER root service driver is unloaded. + */ +static void __exit aer_service_exit(void) +{ + pcie_port_service_unregister(&aerdriver); +} + +module_init(aer_service_init); +module_exit(aer_service_exit); |