11da177e4SLinus Torvalds# 21da177e4SLinus Torvalds# PCI configuration 31da177e4SLinus Torvalds# 41da177e4SLinus Torvaldsconfig PCI_MSI 51da177e4SLinus Torvalds bool "Message Signaled Interrupts (MSI and MSI-X)" 61da177e4SLinus Torvalds depends on PCI 71da177e4SLinus Torvalds depends on (X86_LOCAL_APIC && X86_IO_APIC) || IA64 81da177e4SLinus Torvalds help 91da177e4SLinus Torvalds This allows device drivers to enable MSI (Message Signaled 101da177e4SLinus Torvalds Interrupts). Message Signaled Interrupts enable a device to 111da177e4SLinus Torvalds generate an interrupt using an inbound Memory Write on its 121da177e4SLinus Torvalds PCI bus instead of asserting a device IRQ pin. 131da177e4SLinus Torvalds 14309e57dfSMatthew Wilcox Use of PCI MSI interrupts can be disabled at kernel boot time 15309e57dfSMatthew Wilcox by using the 'pci=nomsi' option. This disables MSI for the 16309e57dfSMatthew Wilcox entire system. 17309e57dfSMatthew Wilcox 181da177e4SLinus Torvalds If you don't know what to do here, say N. 191da177e4SLinus Torvalds 200f397f86SGreg Kroah-Hartmanconfig PCI_MULTITHREAD_PROBE 210f397f86SGreg Kroah-Hartman bool "PCI Multi-threaded probe (EXPERIMENTAL)" 220f397f86SGreg Kroah-Hartman depends on PCI && EXPERIMENTAL 230f397f86SGreg Kroah-Hartman help 240f397f86SGreg Kroah-Hartman Say Y here if you want the PCI core to spawn a new thread for 250f397f86SGreg Kroah-Hartman every PCI device that is probed. This can cause a huge 260f397f86SGreg Kroah-Hartman speedup in boot times on multiprocessor machines, and even a 270f397f86SGreg Kroah-Hartman smaller speedup on single processor machines. 280f397f86SGreg Kroah-Hartman 290f397f86SGreg Kroah-Hartman But it can also cause lots of bad things to happen. A number 300f397f86SGreg Kroah-Hartman of PCI drivers can not properly handle running in this way, 310f397f86SGreg Kroah-Hartman some will just not work properly at all, while others might 320f397f86SGreg Kroah-Hartman decide to blow up power supplies with a huge load all at once, 330f397f86SGreg Kroah-Hartman so use this option at your own risk. 340f397f86SGreg Kroah-Hartman 350f397f86SGreg Kroah-Hartman It is very unwise to use this option if you are not using a 360f397f86SGreg Kroah-Hartman boot process that can handle devices being created in any 370f397f86SGreg Kroah-Hartman order. A program that can create persistant block and network 380f397f86SGreg Kroah-Hartman device names (like udev) is a good idea if you wish to use 390f397f86SGreg Kroah-Hartman this option. 400f397f86SGreg Kroah-Hartman 410f397f86SGreg Kroah-Hartman Again, use this option at your own risk, you have been warned! 420f397f86SGreg Kroah-Hartman 430f397f86SGreg Kroah-Hartman When in doubt, say N. 440f397f86SGreg Kroah-Hartman 451da177e4SLinus Torvaldsconfig PCI_DEBUG 461da177e4SLinus Torvalds bool "PCI Debugging" 471da177e4SLinus Torvalds depends on PCI && DEBUG_KERNEL 481da177e4SLinus Torvalds help 491da177e4SLinus Torvalds Say Y here if you want the PCI core to produce a bunch of debug 501da177e4SLinus Torvalds messages to the system log. Select this if you are having a 511da177e4SLinus Torvalds problem with PCI support and want to see more of what is going on. 521da177e4SLinus Torvalds 531da177e4SLinus Torvalds When in doubt, say N. 541da177e4SLinus Torvalds 55