isa.c revision a734c64bff58bda2fa48c2795453e092167b0ff7
#include <stdint.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <ipxe/io.h>
#include <ipxe/isa.h>
FILE_LICENCE ( GPL2_OR_LATER );
/*
* isa.c implements a "classical" port-scanning method of ISA device
* detection. The driver must provide a list of probe addresses
* (probe_addrs), together with a function (probe_addr) that can be
* used to test for the physical presence of a device at any given
* address.
*
* Note that this should probably be considered the "last resort" for
* device probing. If the card supports ISAPnP or EISA, use that
* instead. Some cards (e.g. the 3c509) implement a proprietary
* ISAPnP-like mechanism.
*
* The ISA probe address list can be overridden by config.h; if the
* user specifies ISA_PROBE_ADDRS then that list will be used first.
* (If ISA_PROBE_ONLY is defined, the driver's own list will never be
* used).
*/
/*
* User-supplied probe address list
*
*/
static isa_probe_addr_t isa_extra_probe_addrs[] = {
#ifdef ISA_PROBE_ADDRS
ISA_PROBE_ADDRS
#endif
};
#define ISA_EXTRA_PROBE_ADDR_COUNT \
( sizeof ( isa_extra_probe_addrs ) / sizeof ( isa_extra_probe_addrs[0] ) )
#define ISA_IOIDX_MIN( driver ) ( -ISA_EXTRA_PROBE_ADDR_COUNT )
#ifdef ISA_PROBE_ONLY
#define ISA_IOIDX_MAX( driver ) ( -1 )
#else
#define ISA_IOIDX_MAX( driver ) ( (int) (driver)->addr_count - 1 )
#endif
#define ISA_IOADDR( driver, ioidx ) \
( ( (ioidx) < 0 ) ? \
isa_extra_probe_addrs[ (ioidx) + ISA_EXTRA_PROBE_ADDR_COUNT ] : \
(driver)->probe_addrs[(ioidx)] )
static void isabus_remove ( struct root_device *rootdev );
/**
* Probe an ISA device
*
* @v isa ISA device
* @ret rc Return status code
*/
static int isa_probe ( struct isa_device *isa ) {
int rc;
DBG ( "Trying ISA driver %s at I/O %04x\n",
isa->driver->name, isa->ioaddr );
if ( ( rc = isa->driver->probe ( isa ) ) != 0 ) {
DBG ( "...probe failed\n" );
return rc;
}
DBG ( "...device found\n" );
return 0;
}
/**
* Remove an ISA device
*
* @v isa ISA device
*/
static void isa_remove ( struct isa_device *isa ) {
isa->driver->remove ( isa );
DBG ( "Removed ISA%04x\n", isa->ioaddr );
}
/**
* Probe ISA root bus
*
* @v rootdev ISA bus root device
*
* Scans the ISA bus for devices and registers all devices it can
* find.
*/
static int isabus_probe ( struct root_device *rootdev ) {
struct isa_device *isa = NULL;
struct isa_driver *driver;
int ioidx;
int rc;
for_each_table_entry ( driver, ISA_DRIVERS ) {
for ( ioidx = ISA_IOIDX_MIN ( driver ) ;
ioidx <= ISA_IOIDX_MAX ( driver ) ; ioidx++ ) {
/* Allocate struct isa_device */
if ( ! isa )
isa = malloc ( sizeof ( *isa ) );
if ( ! isa ) {
rc = -ENOMEM;
goto err;
}
memset ( isa, 0, sizeof ( *isa ) );
isa->driver = driver;
isa->ioaddr = ISA_IOADDR ( driver, ioidx );
/* Add to device hierarchy */
snprintf ( isa->dev.name, sizeof ( isa->dev.name ),
"ISA%04x", isa->ioaddr );
isa->dev.driver_name = driver->name;
isa->dev.desc.bus_type = BUS_TYPE_ISA;
isa->dev.desc.vendor = driver->vendor_id;
isa->dev.desc.device = driver->prod_id;
isa->dev.parent = &rootdev->dev;
list_add ( &isa->dev.siblings,
&rootdev->dev.children );
INIT_LIST_HEAD ( &isa->dev.children );
/* Try probing at this I/O address */
if ( isa_probe ( isa ) == 0 ) {
/* isadev registered, we can drop our ref */
isa = NULL;
} else {
/* Not registered; re-use struct */
list_del ( &isa->dev.siblings );
}
}
}
free ( isa );
return 0;
err:
free ( isa );
isabus_remove ( rootdev );
return rc;
}
/**
* Remove ISA root bus
*
* @v rootdev ISA bus root device
*/
static void isabus_remove ( struct root_device *rootdev ) {
struct isa_device *isa;
struct isa_device *tmp;
list_for_each_entry_safe ( isa, tmp, &rootdev->dev.children,
dev.siblings ) {
isa_remove ( isa );
list_del ( &isa->dev.siblings );
free ( isa );
}
}
/** ISA bus root device driver */
static struct root_driver isa_root_driver = {
.probe = isabus_probe,
.remove = isabus_remove,
};
/** ISA bus root device */
struct root_device isa_root_device __root_device = {
.dev = { .name = "ISA" },
.driver = &isa_root_driver,
};