ISAPNP, isapnp_devmatch, isapnp_config, isapnp_unconfig - Plug 'n' Play
ISA bus
#include <machine/bus.h>
#include <dev/isa/isareg.h>
#include <dev/isa/isavar.h>
#include <dev/isapnp/isapnpreg.h>
#include <dev/isapnp/isapnpvar.h>
#include <dev/isapnp/isapnpdevs.h>
int
isapnp_devmatch(const struct isapnp_attach_args *ipa,
const struct isapnp_devinfo *dinfo, int *variant);
int
isapnp_config(bus_space_tag_t iot, bus_space_tag_t memt,
struct isapnp_attach_args *ipa);
void
isapnp_unconfig(bus_space_tag_t iot, bus_space_tag_t memt,
struct isapnp_attach_args *ipa);
The machine-independent ISAPNP subsystem provides support for ISAPNP
devices. ISAPNP devices were developed to support "plug and play" connection
on the ISA bus. In all other aspects, the ISAPNP bus is same as
the ISA bus (see isa(9)).
Devices on the ISAPNP bus are uniquely identified by a 7-character
string. Resources, such as I/O address space and interrupts, should be
allocated to the devices by the machine firmware. On some machine the
firmware seems doesn't work correctly and NetBSD will attempt to allocate
resources as necessary.
Drivers attached to the ISAPNP bus will make use of the following data
types:
struct isapnp_matchinfo
NetBSD kernel contains a database of known ISAPNP devices. Each
entry in the database has a struct isapnp_matchinfo. It contains
the following members:
const char *name; /* device id string */
int variant; /* variant flag */
struct isapnp_devinfo
Defines the devices supported by a driver. It contains pointer
to an array of supported struct isapnp_matchinfo structures and
a pointer to another array of compatibility devices. It contains
the following members:
struct isapnp_matchinfo *devlogic;
int nlogic;
struct isapnp_matchinfo *devcompat;
int ncompat;
struct isapnp_region
Describes ISAPNP bus-space regions. It contains the following
members:
bus_space_handle_t h;
u_int32_t base;
u_int32_t length;
struct isapnp_pin
Describes the wiring of interrupts and DMA pins from the ISAPNP
bus onto the host processor. It contains the following members:
u_int8_t num;
u_int8_t flags:4;
u_int8_t type:4;
u_int16_t bits;
struct isapnp_attach_args
A structure used to inform the driver of the device properties.
It contains the following members:
bus_space_tag_t ipa_iot; /* isa i/o space tag */
bus_space_tag_t ipa_memt; /* isa mem space tag */
bus_dma_tag_t ipa_dmat; /* isa dma tag */
isa_chipset_tag_t ipa_ic;
struct isapnp_region ipa_io[ISAPNP_NUM_IO];
struct isapnp_region ipa_mem[ISAPNP_NUM_MEM];
struct isapnp_region ipa_mem32[ISAPNP_NUM_MEM32];
struct isapnp_pin ipa_irq[ISAPNP_NUM_IRQ];
struct isapnp_pin ipa_drq[ISAPNP_NUM_DRQ];
isapnp_devmatch(ipa, dinfo, variant)
Matches the device described by the attachment ipa with the
device-match information in dinfo. If the device is matched,
isapnp_devmatch() returns a non-zero value and variant is the
flag describing the device variant. isapnp_devmatch() returns
zero if the device is not found.
isapnp_config(iot, memt, ipa)
Allocate device resources specified by ipa. The device is
mapped into the I/O and memory bus spaces specified by bus-space
tags iot and memt respectively. The ipa_io, ipa_mem, ipa_mem32,
ipa_irq, and ipa_drq members of ipa are updated to reflect the
allocated and mapped resources. isapnp_config() returns zero on
success and non-zero on error.
isapnp_unconfig(iot, memt, ipa)
Free the resources allocated by isapnp_config().
During autoconfiguration, an ISAPNP driver will receive a pointer to
struct isapnp_attach_args describing the device attached to the ISAPNP
bus. Drivers match the device using ispnp_devmatch().
During the driver attach step, driver should initially allocate and map
resources using isapnp_config(). The I/O (memory) bus-space resources
can be accessed using the bus-space tag ipa_iot (ipa_memt) and the busspace
handle ipa_io[0].h (ipa_mem[0].h) members of ipa.
Interrupts should be established using isa_intr_establish() (see isa(9))
with the IRQ specified by the ipa_irq[0].num member of ipa. Similarly,
the standard isa(9) DMA interface should be used with the ipa_drq[0].num
member of ipa.
Extensive DMA facilities are provided through the isa(9) DMA facilities.
This section describes places within the NetBSD source tree where actual
code implementing or utilising the machine-independent ISAPNP subsystem
can be found. All pathnames are relative to /usr/src.
The ISAPNP subsystem itself is implemented within the file
sys/dev/isapnp/isapnp.c. The database of the known devices exists within
the file sys/dev/isapnp/isapnpdevs.c and is generated automatically from
the file sys/dev/isapnp/isapnpdevs. New devices should be added to this
file. The database can be regenerated using the Makefile
sys/dev/isapnp/Makefile.isapnpdevs.
isa(4), isapnp(4), pnpbios(4), autoconf(9), bus_dma(9), bus_space(9),
driver(9), isa(9)
Plug and Play ISA Specification V1.0a, May 5 1994.
The machine-independent ISAPNP subsystem appear in NetBSD 1.3.
BSD June 19, 2001 BSD
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