1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 2000 Alexander Langer 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.\" $FreeBSD$ 30.\" 31.Dd May 18, 2000 32.Dt BUS_ALLOC_RESOURCE 9 33.Os 34.Sh NAME 35.Nm bus_alloc_resource , 36.Nm bus_alloc_resource_any 37.Nd allocate resources from a parent bus 38.Sh SYNOPSIS 39.In sys/param.h 40.In sys/bus.h 41.Pp 42.In machine/bus.h 43.In sys/rman.h 44.In machine/resource.h 45.Ft struct resource * 46.Fn bus_alloc_resource "device_t dev" "int type" "int *rid" "u_long start" "u_long end" "u_long count" "u_int flags" 47.Ft struct resource * 48.Fn bus_alloc_resource_any "device_t dev" "int type" "int *rid" "u_int flags" 49.Sh DESCRIPTION 50This is an easy interface to the resource-management functions. 51It hides the indirection through the parent's method table. 52This function generally should be called in attach, but (except in some 53rare cases) never earlier. 54.Pp 55The 56.Fn bus_alloc_resource_any 57function is a convenience wrapper for 58.Fn bus_alloc_resource . 59It sets the values for 60.Fa start , 61.Fa end , 62and 63.Fa count 64to the default resource (see description of 65.Fa start 66below). 67.Pp 68The arguments are as follows: 69.Bl -item 70.It 71.Fa dev 72is the device that requests ownership of the resource. 73Before allocation, the resource is owned by the parent bus. 74.It 75.Fa type 76is the type of resource you want to allocate. 77It is one of: 78.Bl -tag -width SYS_RES_MEMORY 79.It Dv SYS_RES_IRQ 80for IRQs 81.It Dv SYS_RES_DRQ 82for ISA DMA lines 83.It Dv SYS_RES_IOPORT 84for I/O ports 85.It Dv SYS_RES_MEMORY 86for I/O memory 87.El 88.It 89.Fa rid 90points to a bus specific handle that identifies the resource being allocated. 91For ISA this is an index into an array of resources that have been setup 92for this device by either the PnP mechanism, or via the hints mechanism. 93For PCCARD, this is an index into the array of resources described by the PC Card's 94CIS entry. 95For PCI, the offset into pci config space which has the BAR to use to access 96the resource. 97The bus methods are free to change the RIDs that they are given as a parameter. 98You must not depend on the value you gave it earlier. 99.It 100.Fa start 101and 102.Fa end 103are the start/end addresses of the resource. 104If you specify values of 0ul for 105.Fa start 106and ~0ul for 107.Fa end 108and 1 for 109.Fa count , 110the default values for the bus are calculated. 111.It 112.Fa count 113is the size of the resource. 114For example, the size of an I/O port is usually 1 byte (but some devices 115override this). 116If you specified the default values for 117.Fa start 118and 119.Fa end , 120then the default value of the bus is used if 121.Fa count 122is smaller than the default value and 123.Fa count 124is used, if it is bigger than the default value. 125.It 126.Fa flags 127sets the flags for the resource. 128You can set one or more of these flags: 129.Bl -tag -width RF_SHAREABLE 130.It Dv RF_ALLOCATED 131resource has been reserved. 132The resource still needs to be activated with 133.Xr bus_activate_resource 9 . 134.It Dv RF_ACTIVE 135activate resource atomically. 136.It Dv RF_SHAREABLE 137resource permits contemporaneous sharing. 138It should always be set unless you know that the resource cannot be shared. 139It is the bus driver's task to filter out the flag if the bus does not 140support sharing. 141For example, 142.Xr pccard 4 143cannot share IRQs while 144.Xr cardbus 4 145can. 146.It Dv RF_TIMESHARE 147resource permits time-division sharing. 148.El 149.El 150.Sh RETURN VALUES 151A pointer to 152.Va struct resource 153is returned on success, a null pointer otherwise. 154.Sh EXAMPLES 155This is some example code that allocates a 32 byte I/O port range and an IRQ. 156The values of 157.Va portid 158and 159.Va irqid 160should be saved in the softc of the device after these calls. 161.Bd -literal 162 struct resource *portres, *irqres; 163 int portid, irqid; 164 165 portid = 0; 166 irqid = 0; 167 portres = bus_alloc_resource(dev, SYS_RES_IOPORT, &portid, 168 0ul, ~0ul, 32, RF_ACTIVE); 169 irqres = bus_alloc_resource_any(dev, SYS_RES_IRQ, &irqid, 170 RF_ACTIVE | RF_SHAREABLE); 171.Ed 172.Sh SEE ALSO 173.Xr bus_activate_resource 9 , 174.Xr bus_adjust_resource 9 , 175.Xr bus_release_resource 9 , 176.Xr device 9 , 177.Xr driver 9 178.Sh AUTHORS 179.An -nosplit 180This manual page was written by 181.An Alexander Langer Aq alex@big.endian.de 182with parts by 183.An Warner Losh Aq imp@FreeBSD.org . 184