From 79dd9182db2072d63ccf160bb9a3463b1c952723 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 21 Aug 2010 01:51:44 +0200 Subject: [PATCH] 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 Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 4 ++++ drivers/pci/pcie/portdrv.h | 2 ++ drivers/pci/pcie/portdrv_core.c | 3 +++ drivers/pci/pcie/portdrv_pci.c | 15 +++++++++++++++ 4 files changed, 24 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 873b68090098..b9008fc3a53d 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2042,6 +2042,10 @@ and is between 256 and 4096 characters. It is defined in the file 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 diff --git a/drivers/pci/pcie/portdrv.h b/drivers/pci/pcie/portdrv.h index 813a5c3427b6..966f6e9761c8 100644 --- a/drivers/pci/pcie/portdrv.h +++ b/drivers/pci/pcie/portdrv.h @@ -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 diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c index e73effbe402c..2bf2fe510e15 100644 --- a/drivers/pci/pcie/portdrv_core.c +++ b/drivers/pci/pcie/portdrv_core.c @@ -494,6 +494,9 @@ static void pcie_port_shutdown_service(struct device *dev) {} */ 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; diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c index 3debed25e46b..a04392da6ce1 100644 --- a/drivers/pci/pcie/portdrv_pci.c +++ b/drivers/pci/pcie/portdrv_pci.c @@ -29,6 +29,18 @@ MODULE_AUTHOR(DRIVER_AUTHOR); 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) @@ -301,6 +313,9 @@ static int __init pcie_portdrv_init(void) { int retval; + if (pcie_ports_disabled) + return -EACCES; + dmi_check_system(pcie_portdrv_dmi_table); retval = pcie_port_bus_register();