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diff --git a/share/man/man9/bus_alloc_resource.9 b/share/man/man9/bus_alloc_resource.9 new file mode 100644 index 0000000..78959a0 --- /dev/null +++ b/share/man/man9/bus_alloc_resource.9 @@ -0,0 +1,183 @@ +.\" -*- nroff -*- +.\" +.\" Copyright (c) 2000 Alexander Langer +.\" +.\" All rights reserved. +.\" +.\" This program is free software. +.\" +.\" 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. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``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 DEVELOPERS 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. +.\" +.\" $FreeBSD$ +.\" +.Dd May 18, 2000 +.Dt BUS_ALLOC_RESOURCE 9 +.Os +.Sh NAME +.Nm bus_alloc_resource , +.Nm bus_alloc_resource_any +.Nd allocate resources from a parent bus +.Sh SYNOPSIS +.In sys/param.h +.In sys/bus.h +.Pp +.In machine/bus.h +.In sys/rman.h +.In machine/resource.h +.Ft struct resource * +.Fn bus_alloc_resource "device_t dev" "int type" "int *rid" "u_long start" "u_long end" "u_long count" "u_int flags" +.Ft struct resource * +.Fn bus_alloc_resource_any "device_t dev" "int type" "int *rid" "u_int flags" +.Sh DESCRIPTION +This is an easy interface to the resource-management functions. +It hides the indirection through the parent's method table. +This function generally should be called in attach, but (except in some +rare cases) never earlier. +.Pp +The +.Fn bus_alloc_resource_any +function is a convenience wrapper for +.Fn bus_alloc_resource . +It sets the values for +.Fa start , +.Fa end , +and +.Fa count +to the default resource (see description of +.Fa start +below). +.Pp +The arguments are as follows: +.Bl -item +.It +.Fa dev +is the device that requests ownership of the resource. +Before allocation, the resource is owned by the parent bus. +.It +.Fa type +is the type of resource you want to allocate. +It is one of: +.Bl -tag -width SYS_RES_MEMORY +.It Dv SYS_RES_IRQ +for IRQs +.It Dv SYS_RES_DRQ +for ISA DMA lines +.It Dv SYS_RES_IOPORT +for I/O ports +.It Dv SYS_RES_MEMORY +for I/O memory +.El +.It +.Fa rid +points to a bus specific handle that identifies the resource being allocated. +For ISA this is an index into an array of resources that have been setup +for this device by either the PnP mechanism, or via the hints mechanism. +For PCCARD, this is an index into the array of resources described by the PC Card's +CIS entry. +For PCI, the offset into pci config space which has the BAR to use to access +the resource. +The bus methods are free to change the RIDs that they are given as a parameter. +You must not depend on the value you gave it earlier. +.It +.Fa start +and +.Fa end +are the start/end addresses of the resource. +If you specify values of 0ul for +.Fa start +and ~0ul for +.Fa end +and 1 for +.Fa count , +the default values for the bus are calculated. +.It +.Fa count +is the size of the resource. +For example, the size of an I/O port is usually 1 byte (but some devices +override this). +If you specified the default values for +.Fa start +and +.Fa end , +then the default value of the bus is used if +.Fa count +is smaller than the default value and +.Fa count +is used, if it is bigger than the default value. +.It +.Fa flags +sets the flags for the resource. +You can set one or more of these flags: +.Bl -tag -width RF_SHAREABLE +.It Dv RF_ALLOCATED +resource has been reserved. +The resource still needs to be activated with +.Xr bus_activate_resource 9 . +.It Dv RF_ACTIVE +activate resource atomically. +.It Dv RF_SHAREABLE +resource permits contemporaneous sharing. +It should always be set unless you know that the resource cannot be shared. +It is the bus driver's task to filter out the flag if the bus does not +support sharing. +For example, +.Xr pccard 4 +cannot share IRQs while +.Xr cardbus 4 +can. +.It Dv RF_TIMESHARE +resource permits time-division sharing. +.El +.El +.Sh RETURN VALUES +A pointer to +.Va struct resource +is returned on success, a null pointer otherwise. +.Sh EXAMPLES +This is some example code that allocates a 32 byte I/O port range and an IRQ. +The values of +.Va portid +and +.Va irqid +should be saved in the softc of the device after these calls. +.Bd -literal + struct resource *portres, *irqres; + int portid, irqid; + + portid = 0; + irqid = 0; + portres = bus_alloc_resource(dev, SYS_RES_IOPORT, &portid, + 0ul, ~0ul, 32, RF_ACTIVE); + irqres = bus_alloc_resource_any(dev, SYS_RES_IRQ, &irqid, + RF_ACTIVE | RF_SHAREABLE); +.Ed +.Sh SEE ALSO +.Xr bus_activate_resource 9 , +.Xr bus_adjust_resource 9 , +.Xr bus_release_resource 9 , +.Xr device 9 , +.Xr driver 9 +.Sh AUTHORS +.An -nosplit +This manual page was written by +.An Alexander Langer Aq Mt alex@big.endian.de +with parts by +.An Warner Losh Aq Mt imp@FreeBSD.org . |
