NAME

       agp — generic interface to the Accelerated Graphics Port (AGP)

SYNOPSIS

       device agp

DESCRIPTION

       The agp driver provides uniform, abstract methods for controlling the following devices:

       Ali:     M1541, M1621 and M1671 host to AGP bridges
       AMD:     751, 761 and 762 host to AGP bridges
       ATI:     RS100, RS200, RS250 and RS300 AGP bridges
       Intel:   i820, i840, i845, i850, and i860 host to AGP bridges
       Intel:   i810,  i810-DC100,  i810E,  i815, 830M, 845G, 845M, 852GM, 852GME, 855GM, 855GME, 865G, 915G and
                915GM SVGA controllers
       Intel:   82443BX, 82443GX, 82443LX, 82815, 82820, 82830, 82840, 82845,  82845G,  82850,  82855,  82855GM,
                82860, 82865, 82875P, E7205 and E7505 host to AGP bridges
       NVIDIA:  nForce and nForce2 AGP controllers
       SiS:     530,  540, 550, 620, 630, 645, 645DX, 648, 650, 651, 655, 661, 730, 735, 740, 741, 745, 746, 760
                and 5591 host to AGP bridges
       VIA:     3296, 82C597, 82C598, 82C691, 82C694X, 82C8363, 8235, 8237, 8361, 8367, 8371, 8377, 8501,  8601,
                862x,  8633, 8653, 8703, 8753, 8754, 8763, 8783, KT880, PM800, PM880, PN800, PN880, PT880, XM266
                and XN266 host to PCI bridges

       The most common application of agp is for running X(7) on the Intel i81x controllers.

IOCTLS

       The following ioctl(2) operations can be performed on /dev/agpgart, which are defined in <sys/agpio.h>:

       AGPIOC_INFO
               Returns state of the agp system.  The result is a pointer to the following structure:

               typedef struct _agp_info {
                       agp_version version;  /* version of the driver        */
                       uint32_t bridge_id;   /* bridge vendor/device         */
                       uint32_t agp_mode;    /* mode info of bridge          */
                       off_t aper_base;      /* base of aperture             */
                       size_t aper_size;     /* size of aperture             */
                       size_t pg_total;      /* max pages (swap + system)    */
                       size_t pg_system;     /* max pages (system)           */
                       size_t pg_used;       /* current pages used           */
               } agp_info;

       AGPIOC_ACQUIRE
               Acquire control of the AGP chipset for use by this client.  Returns EBUSY if the AGP  chipset  is
               already acquired by another client.

       AGPIOC_RELEASE
               Release  control of the AGP chipset.  This does not unbind or free any allocated memory, which is
               the responsibility of the client to handle if necessary.

       AGPIOC_SETUP
               Enable the AGP hardware with the relevant mode.  This ioctl(2) takes the following structure:

               typedef struct _agp_setup {
                       uint32_t agp_mode;    /* mode info of bridge */
               } agp_setup;

               The mode bits are defined in <sys/agpio.h>.

       AGPIOC_ALLOCATE
               Allocate physical memory suitable for mapping into the AGP aperture.   This  ioctl(2)  takes  the
               following structure:

               typedef struct _agp_allocate {
                       int key;              /* tag of allocation            */
                       size_t pg_count;      /* number of pages              */
                       uint32_t type;        /* 0 == normal, other devspec   */
                       uint32_t physical;    /* device specific (some devices
                                              * need a phys address of the
                                              * actual page behind the gatt
                                              * table)                       */
               } agp_allocate;

               Returns a handle to the allocated memory.

       AGPIOC_DEALLOCATE
               Free the previously allocated memory associated with the handle passed.

       AGPIOC_BIND
               Bind the allocated memory at given offset with the AGP aperture.  Returns EINVAL if the memory is
               already  bound  or  the  offset  is  not at AGP page boundary.  This ioctl(2) takes the following
               structure:

               typedef struct _agp_bind {
                       int key;         /* tag of allocation            */
                       off_t pg_start;  /* starting page to populate    */
               } agp_bind;

               The tag of allocation is the handle returned by AGPIOC_ALLOCATE.

       AGPIOC_UNBIND
               Unbind memory from the AGP aperture.  Returns EINVAL if the memory is not bound.   This  ioctl(2)
               takes the following structure:

               typedef struct _agp_unbind {
                       int key;                /* tag of allocation         */
                       uint32_t priority;      /* priority for paging out   */
               } agp_unbind;

FILES

       /dev/agpgart  AGP device node.

SEE ALSO

       X(7) (ports/x11/xorg)

HISTORY

       The agp driver first appeared in FreeBSD 4.1.

Debian                                          November 28, 2007                                         AGP(4)