diff options
| -rw-r--r-- | drivers/pci/pci.c | 6 | ||||
| -rw-r--r-- | drivers/pci/probe.c | 14 | ||||
| -rw-r--r-- | include/linux/pci.h | 3 |
3 files changed, 20 insertions, 3 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 4e84fd4a4312..e9651f0a8817 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -77,7 +77,7 @@ unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE; unsigned long pci_hotplug_io_size = DEFAULT_HOTPLUG_IO_SIZE; unsigned long pci_hotplug_mem_size = DEFAULT_HOTPLUG_MEM_SIZE; -enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_SAFE; +enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_TUNE_OFF; /* * The default CLS is used if arch didn't set CLS explicitly and not @@ -3568,10 +3568,14 @@ static int __init pci_setup(char *str) pci_hotplug_io_size = memparse(str + 9, &str); } else if (!strncmp(str, "hpmemsize=", 10)) { pci_hotplug_mem_size = memparse(str + 10, &str); + } else if (!strncmp(str, "pcie_bus_tune_off", 17)) { + pcie_bus_config = PCIE_BUS_TUNE_OFF; } else if (!strncmp(str, "pcie_bus_safe", 13)) { pcie_bus_config = PCIE_BUS_SAFE; } else if (!strncmp(str, "pcie_bus_perf", 13)) { pcie_bus_config = PCIE_BUS_PERFORMANCE; + } else if (!strncmp(str, "pcie_bus_peer2peer", 18)) { + pcie_bus_config = PCIE_BUS_PEER2PEER; } else { printk(KERN_ERR "PCI: Unknown option `%s'\n", str); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index f3f94a5c068f..6ab6bd3df4b2 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1458,12 +1458,24 @@ static int pcie_bus_configure_set(struct pci_dev *dev, void *data) */ void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss) { - u8 smpss = mpss; + u8 smpss; if (!pci_is_pcie(bus->self)) return; + if (pcie_bus_config == PCIE_BUS_TUNE_OFF) + return; + + /* FIXME - Peer to peer DMA is possible, though the endpoint would need + * to be aware to the MPS of the destination. To work around this, + * simply force the MPS of the entire system to the smallest possible. + */ + if (pcie_bus_config == PCIE_BUS_PEER2PEER) + smpss = 0; + if (pcie_bus_config == PCIE_BUS_SAFE) { + smpss = mpss; + pcie_find_smpss(bus->self, &smpss); pci_walk_bus(bus, pcie_find_smpss, &smpss); } diff --git a/include/linux/pci.h b/include/linux/pci.h index 8c230cbcbb48..9fc01226055b 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -621,8 +621,9 @@ struct pci_driver { extern void pcie_bus_configure_settings(struct pci_bus *bus, u8 smpss); enum pcie_bus_config_types { - PCIE_BUS_PERFORMANCE, + PCIE_BUS_TUNE_OFF, PCIE_BUS_SAFE, + PCIE_BUS_PERFORMANCE, PCIE_BUS_PEER2PEER, }; |