1 // SPDX-License-Identifier: GPL-2.0
3 * Purpose: PCI Express Port Bus Driver
4 * Author: Tom Nguyen <tom.l.nguyen@intel.com>
6 * Copyright (C) 2004 Intel
7 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
10 #include <linux/pci.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/init.h>
16 #include <linux/aer.h>
17 #include <linux/dmi.h>
22 /* If this switch is set, PCIe port native services should not be enabled. */
23 bool pcie_ports_disabled;
26 * If the user specified "pcie_ports=native", use the PCIe services regardless
27 * of whether the platform has given us permission. On ACPI systems, this
28 * means we ignore _OSC.
30 bool pcie_ports_native;
32 static int __init pcie_port_setup(char *str)
34 if (!strncmp(str, "compat", 6))
35 pcie_ports_disabled = true;
36 else if (!strncmp(str, "native", 6))
37 pcie_ports_native = true;
41 __setup("pcie_ports=", pcie_port_setup);
46 static int pcie_port_runtime_suspend(struct device *dev)
48 if (!to_pci_dev(dev)->bridge_d3)
51 return pcie_port_device_runtime_suspend(dev);
54 static int pcie_port_runtime_idle(struct device *dev)
57 * Assume the PCI core has set bridge_d3 whenever it thinks the port
58 * should be good to go to D3. Everything else, including moving
59 * the port to D3, is handled by the PCI core.
61 return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
64 static const struct dev_pm_ops pcie_portdrv_pm_ops = {
65 .suspend = pcie_port_device_suspend,
66 .resume_noirq = pcie_port_device_resume_noirq,
67 .resume = pcie_port_device_resume,
68 .freeze = pcie_port_device_suspend,
69 .thaw = pcie_port_device_resume,
70 .poweroff = pcie_port_device_suspend,
71 .restore_noirq = pcie_port_device_resume_noirq,
72 .restore = pcie_port_device_resume,
73 .runtime_suspend = pcie_port_runtime_suspend,
74 .runtime_resume = pcie_port_device_runtime_resume,
75 .runtime_idle = pcie_port_runtime_idle,
78 #define PCIE_PORTDRV_PM_OPS (&pcie_portdrv_pm_ops)
82 #define PCIE_PORTDRV_PM_OPS NULL
86 * pcie_portdrv_probe - Probe PCI-Express port devices
87 * @dev: PCI-Express port device being probed
89 * If detected invokes the pcie_port_device_register() method for
93 static int pcie_portdrv_probe(struct pci_dev *dev,
94 const struct pci_device_id *id)
98 if (!pci_is_pcie(dev) ||
99 ((pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) &&
100 (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM) &&
101 (pci_pcie_type(dev) != PCI_EXP_TYPE_DOWNSTREAM)))
104 status = pcie_port_device_register(dev);
110 dev_pm_set_driver_flags(&dev->dev, DPM_FLAG_NEVER_SKIP |
111 DPM_FLAG_SMART_SUSPEND);
113 if (pci_bridge_d3_possible(dev)) {
115 * Keep the port resumed 100ms to make sure things like
116 * config space accesses from userspace (lspci) will not
117 * cause the port to repeatedly suspend and resume.
119 pm_runtime_set_autosuspend_delay(&dev->dev, 100);
120 pm_runtime_use_autosuspend(&dev->dev);
121 pm_runtime_mark_last_busy(&dev->dev);
122 pm_runtime_put_autosuspend(&dev->dev);
123 pm_runtime_allow(&dev->dev);
129 static void pcie_portdrv_remove(struct pci_dev *dev)
131 if (pci_bridge_d3_possible(dev)) {
132 pm_runtime_forbid(&dev->dev);
133 pm_runtime_get_noresume(&dev->dev);
134 pm_runtime_dont_use_autosuspend(&dev->dev);
137 pcie_port_device_remove(dev);
140 static pci_ers_result_t pcie_portdrv_error_detected(struct pci_dev *dev,
141 enum pci_channel_state error)
143 /* Root Port has no impact. Always recovers. */
144 return PCI_ERS_RESULT_CAN_RECOVER;
147 static pci_ers_result_t pcie_portdrv_slot_reset(struct pci_dev *dev)
149 pci_restore_state(dev);
151 return PCI_ERS_RESULT_RECOVERED;
154 static pci_ers_result_t pcie_portdrv_mmio_enabled(struct pci_dev *dev)
156 return PCI_ERS_RESULT_RECOVERED;
159 static int resume_iter(struct device *device, void *data)
161 struct pcie_device *pcie_device;
162 struct pcie_port_service_driver *driver;
164 if (device->bus == &pcie_port_bus_type && device->driver) {
165 driver = to_service_driver(device->driver);
166 if (driver && driver->error_resume) {
167 pcie_device = to_pcie_device(device);
169 /* Forward error message to service drivers */
170 driver->error_resume(pcie_device->port);
177 static void pcie_portdrv_err_resume(struct pci_dev *dev)
179 device_for_each_child(&dev->dev, NULL, resume_iter);
183 * LINUX Device Driver Model
185 static const struct pci_device_id port_pci_ids[] = {
186 /* handle any PCI-Express port */
187 { PCI_DEVICE_CLASS(((PCI_CLASS_BRIDGE_PCI << 8) | 0x00), ~0) },
188 /* subtractive decode PCI-to-PCI bridge, class type is 060401h */
189 { PCI_DEVICE_CLASS(((PCI_CLASS_BRIDGE_PCI << 8) | 0x01), ~0) },
193 static const struct pci_error_handlers pcie_portdrv_err_handler = {
194 .error_detected = pcie_portdrv_error_detected,
195 .slot_reset = pcie_portdrv_slot_reset,
196 .mmio_enabled = pcie_portdrv_mmio_enabled,
197 .resume = pcie_portdrv_err_resume,
200 static struct pci_driver pcie_portdriver = {
202 .id_table = &port_pci_ids[0],
204 .probe = pcie_portdrv_probe,
205 .remove = pcie_portdrv_remove,
206 .shutdown = pcie_portdrv_remove,
208 .err_handler = &pcie_portdrv_err_handler,
210 .driver.pm = PCIE_PORTDRV_PM_OPS,
213 static int __init dmi_pcie_pme_disable_msi(const struct dmi_system_id *d)
215 pr_notice("%s detected: will not use MSI for PCIe PME signaling\n",
217 pcie_pme_disable_msi();
221 static const struct dmi_system_id pcie_portdrv_dmi_table[] __initconst = {
223 * Boxes that should not use MSI for PCIe PME signaling.
226 .callback = dmi_pcie_pme_disable_msi,
227 .ident = "MSI Wind U-100",
229 DMI_MATCH(DMI_SYS_VENDOR,
230 "MICRO-STAR INTERNATIONAL CO., LTD"),
231 DMI_MATCH(DMI_PRODUCT_NAME, "U-100"),
237 static void __init pcie_init_services(void)
243 pcie_bandwidth_notification_init();
246 static int __init pcie_portdrv_init(void)
248 if (pcie_ports_disabled)
251 pcie_init_services();
252 dmi_check_system(pcie_portdrv_dmi_table);
254 return pci_register_driver(&pcie_portdriver);
256 device_initcall(pcie_portdrv_init);