--- /dev/null
+/*
+ * 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);
Code Review / kvmfornfv.git / blobdiff