1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 2003 M. Warner Losh <imp@FreeBSD.org> 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 15.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 18.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24.\" 25.Dd May 20, 2016 26.Dt BUS_ACTIVATE_RESOURCE 9 27.Os 28.Sh NAME 29.Nm bus_activate_resource , bus_deactivate_resource 30.Nd activate or deactivate a resource 31.Sh SYNOPSIS 32.In sys/param.h 33.In sys/bus.h 34.Pp 35.In machine/bus.h 36.In sys/rman.h 37.In machine/resource.h 38.Ft int 39.Fo bus_activate_resource 40.Fa "device_t dev" "int type" "int rid" "struct resource *r" 41.Fc 42.Ft int 43.Fo bus_deactivate_resource 44.Fa "device_t dev" "int type" "int rid" "struct resource *r" 45.Fc 46.Sh DESCRIPTION 47These functions activate or deactivate a previously allocated resource. 48In general, resources must be activated before they can be accessed by 49the driver. 50Bus drivers may perform additional actions to ensure that the resource is 51ready to be accessed. 52For example, 53the PCI bus driver enables memory decoding in a PCI device's command register 54when activating a memory resource. 55.Pp 56The arguments are as follows: 57.Bl -tag -width indent 58.It Fa dev 59The device that requests ownership of the resource. 60Before allocation, the resource is owned by the parent bus. 61.It Fa type 62The type of resource you want to allocate. 63It is one of: 64.Pp 65.Bl -tag -width ".Dv SYS_RES_MEMORY" -compact 66.It Dv PCI_RES_BUS 67for PCI bus numbers 68.It Dv SYS_RES_IRQ 69for IRQs 70.It Dv SYS_RES_DRQ 71for ISA DMA lines 72.It Dv SYS_RES_IOPORT 73for I/O ports 74.It Dv SYS_RES_MEMORY 75for I/O memory 76.El 77.It Fa rid 78A pointer to a bus specific handle that identifies the resource being allocated. 79.It Fa r 80A pointer to the 81.Vt "struct resource" 82returned by 83.Xr bus_alloc_resource 9 . 84.El 85.Ss Resource Mapping 86Resources which can be mapped for CPU access by a 87.Xr bus_space 9 88tag and handle will create a mapping of the entire resource when activated. 89The tag and handle for this mapping are stored in 90.Fa r 91and can be retrieved via 92.Xr rman_get_bustag 9 93and 94.Xr rman_get_bushandle 9 . 95These can be used with the 96.Xr bus_space 9 97API to access device registers or memory described by 98.Fa r . 99If the mapping is associated with a virtual address, 100the virtual address can be retrieved via 101.Xr rman_get_virtual 9 . 102.Pp 103This implicit mapping can be disabled by passing the 104.Dv RF_UNMAPPED 105flag to 106.Xr bus_alloc_resource 9 . 107A driver may use this if it wishes to allocate its own mappings of a resource 108using 109.Xr bus_map_resource 9 . 110.Pp 111A wrapper API for 112.Xr bus_space 9 113is also provided that accepts the associated resource as the first argument 114in place of the 115.Xr bus_space 9 116tag and handle. 117The functions in this wrapper API are named similarly to the 118.Xr bus_space 9 119API except that 120.Dq _space 121is removed from their name. 122For example, 123.Fn bus_read_4 124can be used in place of 125.Fn bus_space_read_4 . 126The wrapper API is preferred in new drivers. 127.Pp 128These two statements both read a 32-bit register at the start of a 129resource: 130.Bd -literal 131 bus_space_read_4(rman_get_bustag(res), rman_get_bushandle(res), 0); 132 bus_read_4(res, 0); 133.Ed 134.Sh RETURN VALUES 135Zero is returned on success, otherwise an error is returned. 136.Sh SEE ALSO 137.Xr bus_alloc_resource 9 , 138.Xr bus_map_resource 9 , 139.Xr bus_space 9 , 140.Xr device 9 , 141.Xr driver 9 142.Sh AUTHORS 143This manual page was written by 144.An Warner Losh Aq Mt imp@FreeBSD.org . 145