.\" $OpenBSD: pcibios.4,v 1.22 2007/05/31 19:19:55 jmc Exp $ .\" $NetBSD: pcibios.4,v 1.7 2000/08/03 13:32:39 soda Exp $ .\" .\" Copyright (c) 2000 Michael Shalayeff, All rights reserved. .\" Copyright (c) 1999, 2000 The NetBSD Foundation, Inc. .\" All rights reserved. .\" .\" This code is derived from software contributed to The NetBSD Foundation .\" by Lennart Augustsson. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the NetBSD .\" Foundation, Inc. and its contributors. .\" 4. Neither the name of The NetBSD Foundation nor the names of its .\" contributors may be used to endorse or promote products derived .\" from this software without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS .\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED .\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR .\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS .\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .Dd $Mdocdate: May 31 2007 $ .Dt PCIBIOS 4 i386 .Os .Sh NAME .Nm pcibios .Nd introduction to PCI BIOS support .Sh SYNOPSIS .Cd "pcibios0 at bios0 flags 0x0000" .\" .Cd "#option PCIBIOS_IRQS_HINT=0x0a00 #IRQ 9,11" .\" .Cd "#option PCIBIOS_INTR_FIXUP_FORCE" .Sh DESCRIPTION .Ox provides support for setting up PCI controllers, bridges, and devices using information extracted from the BIOS. .Pp Ideally, the boot firmware of a machine (a.k.a. BIOS) should set up all PCI devices; assigning them I/O and memory addresses and interrupts. Alas, this does not always happen, so there is some PC specific code that can do the initialization when .Ox boots. .Pp Flags is a bit mask each bit of which specifies a fixup procedure to omit. The following list specifies these procedures and gives flags bit values to disable them in case they cause problems. .Bl -tag -width 0x0000 .It 0x0001 Fixup PCI I/O and memory addresses. .Pp Some BIOS implementations don't allocate I/O space and memory space for all PCI devices. Especially, a BIOS which has .Qq PnP OS mode enabled shows this behavior. Since necessary space isn't allocated, those devices will not work without special handling. .Pp Without this flag force allocation of I/O space and memory space instead of relying upon the BIOS to do so. .Pp If necessary space is already correctly assigned to the devices, this option leaves the space as is. .Pp Although many BIOS implementations leave CardBus bridges' space unallocated, the CardBus bridge device driver doesn't require this option, since the driver allocates necessary space by itself. .It 0x0002 Fixup PCI bus numbering; needed for many .Xr cardbus 4 bridges. .Pp Each PCI bus and CardBus should have a unique bus number. But some BIOS implementations don't assign a bus number for subordinate PCI buses. And many BIOS implementations don't assign a bus number for CardBuses. .Pp A typical symptom of this is the following boot message: .D1 Sy cardbus0 at cardslot0: bus 0 device 0... Please note that this cardbus0 has a bus number .Sq 0 , but normally the bus number 0 is used by the machine's primary PCI bus. Thus, this bus number for cardbus is incorrect .Pq not assigned . In this situation, a device located in cardbus0 doesn't show correct device ID, because its bus number 0 incorrectly refers to the primary PCI bus, and a device ID in the primary PCI bus is shown in the boot message instead of the device's ID in the cardbus0. .Pp Without this flag force assignment of bus numbers for all subordinate PCI buses and CardBuses. .Pp Since this procedure renumbers all PCI buses and CardBuses, all bus numbers of subordinate buses become different when this option is enabled. .It 0x0004 Fixup PCI interrupt routing. .Pp Some BIOS implementations don't assign an interrupt for some devices. .Pp This procedure assigns an interrupt for such devices instead of relying upon the BIOS to do so. .Pp If the BIOS has already assigned an interrupt to a device, this procedure leaves the interrupt as is. .It 0x0008 Make PCI interrupt routing fixup work with unknown interrupt routers. If this flag is specified and a PCI interrupt routing table entry indicates that only one IRQ is available for the entry, the IRQ is assumed to be already connected to the device, and the corresponding PCI Interrupt Configuration Register will be configured accordingly. .Pp Without this flag, if a PCI interrupt router is not known, interrupt configuration will not be modified. .It 0x0010 Be verbose when performing .Nm tasks. Included in these diagnostics are: PCI device address fixup tables, interrupt fixup reports, and other diagnostic and non-fatal messages. .It 0x0020 Make the PCI interrupt routing fixup procedure verbose. .It 0x0040 Some buggy BIOS implementations provide inconsistent information between the PCI Interrupt Configuration Register and the PCI Interrupt Routing table. In such cases, the PCI Interrupt Configuration Register takes precedence by default. If this flag is specified the PCI Interrupt Routing table takes precedence. .El .\" .It Nm PCIBIOS_IRQS_HINT .\" hint for IRQ use. .\" When the .\" .Em PCIBIOS_INTR_FIXUP .\" cannot guess an adequate IRQ for a device, the hint is used. .\" .Pp .\" The value is a logical or of power-of-2s of allowable interrupts: .\" .Bl -column "XX-0xffff" "XX-0xffff" "XX-0xffff" "XX-0xffff" -compact -offset 2n .\" .It Em "IRQ Value" Em "\tIRQ Value" Em "\tIRQ Value" Em "\tIRQ Value" .\" .It "\& 0 0x0001" "\t 4 0x0010" "\t 8 0x0100" "\t12 0x1000" .\" .It "\& 1 0x0002" "\t 5 0x0020" "\t 9 0x0200" "\t13 0x2000" .\" .It "\& 2 0x0004" "\t 6 0x0040" "\t10 0x0400" "\t14 0x4000" .\" .It "\& 3 0x0008" "\t 7 0x0080" "\t11 0x0800" "\t15 0x8000" .\" .El .\" For example, .\" .Qq Sy option PCIBIOS_IRQS_HINT=0x0a00 .\" allows IRQ 9 and IRQ 11. .\" .\" The kernel global variable .\" .Va pcibios_irqs_hint .\" holds this value, .\" so a user can override this value without kernel recompilation. .\" For example: .\" .Bl -bullet -compact .\" .It .\" To specify this value on the fly, type the following command .\" at the boot prompt to drop into DDB (the in-kernel debugger; .\" you have to specify .\" .Qq Sy option DDB .\" to make kernel with DDB): .\" .Dl Ic boot -d .\" And type the following command on .\" .Qq Sy db> .\" prompt: .\" .Dl Ic write pcibios_irqs_hint 0x0a00 .\" Then type the following to continue to boot: .\" .Dl Ic c .\" .It .\" To modify kernel image without kernel recompilation, .\" run the following command on shell: .\" .Dl Ic gdb --write /netbsd .\" And type the following commands at the .\" .Qq Sy (gdb) .\" prompt: .\" .Dl Ic set pcibios_irqs_hint=0xa00 .\" .Dl Ic quit .\" .El .\" .Sh SEE ALSO .Xr bios 4 , .Xr intro 4 , .Xr pci 4 , .Xr pci_conf_read 9 , .Xr pci_intr_map 9 .Sh HISTORY The .Nm code appeared in .Nx 1.5 . .Ox support was added in .Ox 2.8 . In contrast to .Nx implementation .Nm in .Ox is a real device, where options control is done through the .Nm flags which are modifiable through the .Xr boot_config 8 interface. For .Ox 2.9 the PCI interrupt routing establishment sequence was redone to only fixup and route interrupts when attaching interrupts for a particular PCI device. .Sh BUGS The .Em PCIBIOS Address Fixup option may conflict with the PCI CardBus driver's own address fixup.