From 5f39e6705faade2e89d119958a8c51b9b6e2c53c Mon Sep 17 00:00:00 2001 From: Jon Mason Date: Mon, 3 Oct 2011 09:50:20 -0500 Subject: PCI: Disable MPS configuration by default Add the ability to disable PCI-E MPS turning and using the BIOS configured MPS defaults. Due to the number of issues recently discovered on some x86 chipsets, make this the default behavior. Also, add the option for peer to peer DMA MPS configuration. Peer to peer DMA is outside the scope of this patch, but MPS configuration could prevent it from working by having the MPS on one root port different than the MPS on another. To work around this, simply make the system wide MPS the smallest possible value (128B). Signed-off-by: Jon Mason Acked-by: Benjamin Herrenschmidt Signed-off-by: Linus Torvalds --- drivers/pci/pci.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'drivers/pci/pci.c') 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); -- cgit v1.2.3