PCI: PCIe: Introduce commad line switch for disabling port services

Introduce kernel command line switch pcie_ports= allowing one to disable all of the native PCIe port services, so that PCIe ports are treated like PCI-to-PCI bridges. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: PCIe: Introduce commad line switch for disabling port services
Introduce kernel command line switch pcie_ports= allowing one to disable all of the native PCIe port services, so that PCIe ports are treated like PCI-to-PCI bridges. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Rafael J. Wysocki · Jesse Barnes
1 parent f1a7bfaf6b
Showing 4 changed files with 24 additions and 0 deletions Side-by-side Diff
Documentation/kernel-parameters.txt
drivers/pci/pcie/portdrv.h
drivers/pci/pcie/portdrv_core.c
drivers/pci/pcie/portdrv_pci.c
@@ -2042,6 +2042,10 @@
 		force	Enable ASPM even on devices that claim not to support it.
 			WARNING: Forcing ASPM on may cause system lockups.
  
+	pcie_ports=	[PCIE] PCIe ports handling:
+		compat	Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe
+			ports driver.
+
 	pcie_pme=	[PCIE,PM] Native PCIe PME signaling options:
 			Format: {auto|force}[,nomsi]
 		auto	Use native PCIe PME signaling if the BIOS allows the
@@ -20,6 +20,8 @@
  
 #define get_descriptor_id(type, service) (((type - 4) << 4) | service)
  
+extern bool pcie_ports_disabled;
+
 extern struct bus_type pcie_port_bus_type;
 extern int pcie_port_device_register(struct pci_dev *dev);
 #ifdef CONFIG_PM
@@ -494,6 +494,9 @@
  */
 int pcie_port_service_register(struct pcie_port_service_driver *new)
 {
+	if (pcie_ports_disabled)
+		return -ENODEV;
+
 	new->driver.name = (char *)new->name;
 	new->driver.bus = &pcie_port_bus_type;
 	new->driver.probe = pcie_port_probe_service;
@@ -29,6 +29,18 @@
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL");
  
+/* If this switch is set, PCIe port native services should not be enabled. */
+bool pcie_ports_disabled;
+
+static int __init pcie_port_setup(char *str)
+{
+	if (!strncmp(str, "compat", 6))
+		pcie_ports_disabled = true;
+
+	return 1;
+}
+__setup("pcie_ports=", pcie_port_setup);
+
 /* global data */
  
 static int pcie_portdrv_restore_config(struct pci_dev *dev)
@@ -300,6 +312,9 @@
 static int __init pcie_portdrv_init(void)
 {
 	int retval;
+
+	if (pcie_ports_disabled)
+		return -EACCES;
  
 	dmi_check_system(pcie_portdrv_dmi_table);
...	...	@@ -2042,6 +2042,10 @@
2042	2042	force Enable ASPM even on devices that claim not to support it.
2043	2043	WARNING: Forcing ASPM on may cause system lockups.
2044	2044
	2045	+ pcie_ports= [PCIE] PCIe ports handling:
	2046	+ compat Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe
	2047	+ ports driver.
	2048	+
2045	2049	pcie_pme= [PCIE,PM] Native PCIe PME signaling options:
2046	2050	Format: {auto\|force}[,nomsi]
2047	2051	auto Use native PCIe PME signaling if the BIOS allows the
...	...	@@ -20,6 +20,8 @@
20	20
21	21	#define get_descriptor_id(type, service) (((type - 4) << 4) \| service)
22	22
	23	+extern bool pcie_ports_disabled;
	24	+
23	25	extern struct bus_type pcie_port_bus_type;
24	26	extern int pcie_port_device_register(struct pci_dev *dev);
25	27	#ifdef CONFIG_PM
...	...	@@ -494,6 +494,9 @@
494	494	*/
495	495	int pcie_port_service_register(struct pcie_port_service_driver *new)
496	496	{
	497	+ if (pcie_ports_disabled)
	498	+ return -ENODEV;
	499	+
497	500	new->driver.name = (char *)new->name;
498	501	new->driver.bus = &pcie_port_bus_type;
499	502	new->driver.probe = pcie_port_probe_service;
...	...	@@ -29,6 +29,18 @@
29	29	MODULE_DESCRIPTION(DRIVER_DESC);
30	30	MODULE_LICENSE("GPL");
31	31
	32	+/* If this switch is set, PCIe port native services should not be enabled. */
	33	+bool pcie_ports_disabled;
	34	+
	35	+static int __init pcie_port_setup(char *str)
	36	+{
	37	+ if (!strncmp(str, "compat", 6))
	38	+ pcie_ports_disabled = true;
	39	+
	40	+ return 1;
	41	+}
	42	+__setup("pcie_ports=", pcie_port_setup);
	43	+
32	44	/* global data */
33	45
34	46	static int pcie_portdrv_restore_config(struct pci_dev *dev)
...	...	@@ -300,6 +312,9 @@
300	312	static int __init pcie_portdrv_init(void)
301	313	{
302	314	int retval;
	315	+
	316	+ if (pcie_ports_disabled)
	317	+ return -EACCES;
303	318
304	319	dmi_check_system(pcie_portdrv_dmi_table);
305	320