3 * Purpose: PCI Express Port Bus Driver
4 * Author: Tom Nguyen <tom.l.nguyen@intel.com>
7 * Copyright (C) 2004 Intel
8 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
11 #include <linux/pci.h>
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/init.h>
17 #include <linux/pcieport_if.h>
18 #include <linux/aer.h>
19 #include <linux/dmi.h>
20 #include <linux/pci-aspm.h>
25 /* If this switch is set, PCIe port native services should not be enabled. */
26 bool pcie_ports_disabled;
29 * If this switch is set, ACPI _OSC will be used to determine whether or not to
30 * enable PCIe port native services.
32 bool pcie_ports_auto = true;
34 static int __init pcie_port_setup(char *str)
36 if (!strncmp(str, "compat", 6)) {
37 pcie_ports_disabled = true;
38 } else if (!strncmp(str, "native", 6)) {
39 pcie_ports_disabled = false;
40 pcie_ports_auto = false;
41 } else if (!strncmp(str, "auto", 4)) {
42 pcie_ports_disabled = false;
43 pcie_ports_auto = true;
48 __setup("pcie_ports=", pcie_port_setup);
53 * pcie_clear_root_pme_status - Clear root port PME interrupt status.
54 * @dev: PCIe root port or event collector.
56 void pcie_clear_root_pme_status(struct pci_dev *dev)
58 pcie_capability_set_dword(dev, PCI_EXP_RTSTA, PCI_EXP_RTSTA_PME);
61 static int pcie_portdrv_restore_config(struct pci_dev *dev)
65 retval = pci_enable_device(dev);
73 static int pcie_port_resume_noirq(struct device *dev)
75 struct pci_dev *pdev = to_pci_dev(dev);
78 * Some BIOSes forget to clear Root PME Status bits after system wakeup
79 * which breaks ACPI-based runtime wakeup on PCI Express, so clear those
80 * bits now just in case (shouldn't hurt).
82 if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
83 pcie_clear_root_pme_status(pdev);
87 static int pcie_port_runtime_suspend(struct device *dev)
89 return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
92 static int pcie_port_runtime_resume(struct device *dev)
97 static int pcie_port_runtime_idle(struct device *dev)
100 * Assume the PCI core has set bridge_d3 whenever it thinks the port
101 * should be good to go to D3. Everything else, including moving
102 * the port to D3, is handled by the PCI core.
104 return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
107 static const struct dev_pm_ops pcie_portdrv_pm_ops = {
108 .suspend = pcie_port_device_suspend,
109 .resume = pcie_port_device_resume,
110 .freeze = pcie_port_device_suspend,
111 .thaw = pcie_port_device_resume,
112 .poweroff = pcie_port_device_suspend,
113 .restore = pcie_port_device_resume,
114 .resume_noirq = pcie_port_resume_noirq,
115 .runtime_suspend = pcie_port_runtime_suspend,
116 .runtime_resume = pcie_port_runtime_resume,
117 .runtime_idle = pcie_port_runtime_idle,
120 #define PCIE_PORTDRV_PM_OPS (&pcie_portdrv_pm_ops)
124 #define PCIE_PORTDRV_PM_OPS NULL
128 * pcie_portdrv_probe - Probe PCI-Express port devices
129 * @dev: PCI-Express port device being probed
131 * If detected invokes the pcie_port_device_register() method for
135 static int pcie_portdrv_probe(struct pci_dev *dev,
136 const struct pci_device_id *id)
140 if (!pci_is_pcie(dev) ||
141 ((pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) &&
142 (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM) &&
143 (pci_pcie_type(dev) != PCI_EXP_TYPE_DOWNSTREAM)))
146 status = pcie_port_device_register(dev);
152 if (pci_bridge_d3_possible(dev)) {
154 * Keep the port resumed 100ms to make sure things like
155 * config space accesses from userspace (lspci) will not
156 * cause the port to repeatedly suspend and resume.
158 pm_runtime_set_autosuspend_delay(&dev->dev, 100);
159 pm_runtime_use_autosuspend(&dev->dev);
160 pm_runtime_mark_last_busy(&dev->dev);
161 pm_runtime_put_autosuspend(&dev->dev);
162 pm_runtime_allow(&dev->dev);
168 static void pcie_portdrv_remove(struct pci_dev *dev)
170 if (pci_bridge_d3_possible(dev)) {
171 pm_runtime_forbid(&dev->dev);
172 pm_runtime_get_noresume(&dev->dev);
173 pm_runtime_dont_use_autosuspend(&dev->dev);
176 pcie_port_device_remove(dev);
179 static pci_ers_result_t pcie_portdrv_error_detected(struct pci_dev *dev,
180 enum pci_channel_state error)
182 /* Root Port has no impact. Always recovers. */
183 return PCI_ERS_RESULT_CAN_RECOVER;
186 static pci_ers_result_t pcie_portdrv_mmio_enabled(struct pci_dev *dev)
188 return PCI_ERS_RESULT_RECOVERED;
191 static pci_ers_result_t pcie_portdrv_slot_reset(struct pci_dev *dev)
193 /* If fatal, restore cfg space for possible link reset at upstream */
194 if (dev->error_state == pci_channel_io_frozen) {
195 dev->state_saved = true;
196 pci_restore_state(dev);
197 pcie_portdrv_restore_config(dev);
198 pci_enable_pcie_error_reporting(dev);
201 return PCI_ERS_RESULT_RECOVERED;
204 static int resume_iter(struct device *device, void *data)
206 struct pcie_device *pcie_device;
207 struct pcie_port_service_driver *driver;
209 if (device->bus == &pcie_port_bus_type && device->driver) {
210 driver = to_service_driver(device->driver);
211 if (driver && driver->error_resume) {
212 pcie_device = to_pcie_device(device);
214 /* Forward error message to service drivers */
215 driver->error_resume(pcie_device->port);
222 static void pcie_portdrv_err_resume(struct pci_dev *dev)
224 device_for_each_child(&dev->dev, NULL, resume_iter);
228 * LINUX Device Driver Model
230 static const struct pci_device_id port_pci_ids[] = { {
231 /* handle any PCI-Express port */
232 PCI_DEVICE_CLASS(((PCI_CLASS_BRIDGE_PCI << 8) | 0x00), ~0),
233 }, { /* end: all zeroes */ }
236 static const struct pci_error_handlers pcie_portdrv_err_handler = {
237 .error_detected = pcie_portdrv_error_detected,
238 .mmio_enabled = pcie_portdrv_mmio_enabled,
239 .slot_reset = pcie_portdrv_slot_reset,
240 .resume = pcie_portdrv_err_resume,
243 static struct pci_driver pcie_portdriver = {
245 .id_table = &port_pci_ids[0],
247 .probe = pcie_portdrv_probe,
248 .remove = pcie_portdrv_remove,
250 .err_handler = &pcie_portdrv_err_handler,
252 .driver.pm = PCIE_PORTDRV_PM_OPS,
255 static int __init dmi_pcie_pme_disable_msi(const struct dmi_system_id *d)
257 pr_notice("%s detected: will not use MSI for PCIe PME signaling\n",
259 pcie_pme_disable_msi();
263 static const struct dmi_system_id pcie_portdrv_dmi_table[] __initconst = {
265 * Boxes that should not use MSI for PCIe PME signaling.
268 .callback = dmi_pcie_pme_disable_msi,
269 .ident = "MSI Wind U-100",
271 DMI_MATCH(DMI_SYS_VENDOR,
272 "MICRO-STAR INTERNATIONAL CO., LTD"),
273 DMI_MATCH(DMI_PRODUCT_NAME, "U-100"),
279 static int __init pcie_portdrv_init(void)
283 if (pcie_ports_disabled)
284 return pci_register_driver(&pcie_portdriver);
286 dmi_check_system(pcie_portdrv_dmi_table);
288 retval = pcie_port_bus_register();
290 printk(KERN_WARNING "PCIE: bus_register error: %d\n", retval);
293 retval = pci_register_driver(&pcie_portdriver);
295 pcie_port_bus_unregister();
299 device_initcall(pcie_portdrv_init);