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.Nd alloc resources on a bus 37.Sh SYNOPSIS 38.In sys/param.h 39.In sys/bus.h 40.Pp 41.In machine/bus.h 42.In sys/rman.h 43.In machine/resource.h 44.Ft struct resource * 45.Fn bus_alloc_resource "device_t dev" "int type" "int *rid" "u_long start" "u_long end" "u_long count" "u_int flags" 46.Sh DESCRIPTION 47This is an easy interface to the resource-management functions. 48It hides the indirection through the parent's method table. 49This function generally should be called in attach, but (except in some 50rare cases) never earlier. 51.Pp 52Its arguments are as follows: 53.Bl -item 54.It 55.Fa dev 56is the device that requests ownership of the resource. 57Before allocation, the resource is owned by the parent bus. 58.It 59.Fa type 60is the type of resource you want to allocate. 61It is one of: 62.Bl -tag -width SYS_RES_MEMORY 63.It Dv SYS_RES_IRQ 64for IRQs 65.It Dv SYS_RES_DRQ 66for ISA DMA lines 67.It Dv SYS_RES_IOPORT 68for I/O ports 69.It Dv SYS_RES_MEMORY 70for I/O memory 71.El 72.It 73.Fa rid 74points to a bus specific handle that identifies the resource being allocated. 75For ISA this is an index into an array of resources that have been setup 76for this device by either the PnP mechanism, or via the hints mechanism. 77For PCCARD, similar things are used as of writing, 78but that may change in the future with newcard. 79For PCI it just happens to be the offset into pci config space which has 80a word that describes the resource. 81The bus methods are free to change the RIDs that they are given as a parameter. 82You must not depend on the value you gave it earlier. 83.It 84.Fa start 85and 86.Fa end 87are the start/end addresses of the resource. 88If you specify values of 89.Dv 0 90for 91.Fa start 92and 93.Dv ~0 94for 95.Fa end 96and 97.Dv 1 98for 99.Fa count , 100the default values for the bus are calculated. 101.It 102.Fa count 103is the size of the resource, e.g. the size of an I/O port (often 104.Dv 1, but some devices override this). 105If you specified the default values for 106.Fa start 107and 108.Fa end , 109then the default value of the bus is used if 110.Fa count 111is smaller than the default value and 112.Fa count 113is used, if it is bigger as the default value. 114.It 115.Fa flags 116sets the flags for the resource. 117You can set one or more of these flags: 118.Bl -tag -width RF_SHAREABLE 119.It Dv RF_ALLOCATED 120resource has been reserved. 121The resource still needs to be activated with 122.Xr bus_activate_resource 9 . 123.It Dv RF_ACTIVE 124activate resource atomically. 125.It Dv RF_SHAREABLE 126resource permits contemporaneous sharing. 127Should always be set unless you know, that the resource cannot be shared. 128It is the bus-code's task to filter out the flag if the bus doesn't 129support sharing, which is, for example, the case for pccard/cardbus, 130which can or cannot share devices, depending on the bus. 131.It Dv RF_TIMESHARE 132resource permits time-division sharing. 133.El 134.El 135.Sh RETURN VALUES 136A pointer to 137.Va struct res 138is returned on success, a null pointer otherwise. 139.Sh EXAMPLES 140This is some example code. 141The values of 142.Va portid 143and 144.Va irqid 145should be saved in the softc of the device after these calls. 146.Bd -literal 147 struct resource *portres, irqres; 148 int portid, irqid; 149 150 portid = 0; 151 irqid = 0; 152 portres = bus_alloc_resource(dev, SYS_RES_IOPORT, &portid, 153 0ul, ~0ul, 32, RF_ACTIVE); 154 irqres = bus_alloc_resource(dev, SYS_RES_IRQ, &irqid, 155 0ul, ~0ul, 1, RF_ACTIVE | RF_SHAREABLE); 156.Ed 157.Sh SEE ALSO 158.Xr bus_activate_resource 9 , 159.Xr bus_release_resource 9 , 160.Xr device 9 , 161.Xr driver 9 162.Sh AUTHORS 163.An -nosplit 164This man page was written by 165.An Alexander Langer Aq alex@big.endian.de 166with parts by 167.An Warner Losh Aq imp@FreeBSD.org . 168