src/drivers/bus/isa.c

   1 #include <stdint.h>
   2 #include <string.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <errno.h>
   6 #include <gpxe/io.h>
   7 #include <gpxe/isa.h>
   8
   9 FILE_LICENCE ( GPL2_OR_LATER );
  10
  11 /*
  12  * isa.c implements a "classical" port-scanning method of ISA device
  13  * detection.  The driver must provide a list of probe addresses
  14  * (probe_addrs), together with a function (probe_addr) that can be
  15  * used to test for the physical presence of a device at any given
  16  * address.
  17  *
  18  * Note that this should probably be considered the "last resort" for
  19  * device probing.  If the card supports ISAPnP or EISA, use that
  20  * instead.  Some cards (e.g. the 3c509) implement a proprietary
  21  * ISAPnP-like mechanism.
  22  *
  23  * The ISA probe address list can be overridden by config.h; if the
  24  * user specifies ISA_PROBE_ADDRS then that list will be used first.
  25  * (If ISA_PROBE_ONLY is defined, the driver's own list will never be
  26  * used).
  27  */
  28
  29 /*
  30  * User-supplied probe address list
  31  *
  32  */
  33 static isa_probe_addr_t isa_extra_probe_addrs[] = {
  34 #ifdef ISA_PROBE_ADDRS
  35         ISA_PROBE_ADDRS
  36 #endif
  37 };
  38 #define ISA_EXTRA_PROBE_ADDR_COUNT \
  39      ( sizeof ( isa_extra_probe_addrs ) / sizeof ( isa_extra_probe_addrs[0] ) )
  40
  41 #define ISA_IOIDX_MIN( driver ) ( -ISA_EXTRA_PROBE_ADDR_COUNT )
  42 #ifdef ISA_PROBE_ONLY
  43 #define ISA_IOIDX_MAX( driver ) ( -1 )
  44 #else
  45 #define ISA_IOIDX_MAX( driver ) ( (int) (driver)->addr_count - 1 )
  46 #endif
  47
  48 #define ISA_IOADDR( driver, ioidx )                                       \
  49         ( ( (ioidx) < 0 ) ?                                               \
  50           isa_extra_probe_addrs[ (ioidx) + ISA_EXTRA_PROBE_ADDR_COUNT ] : \
  51           (driver)->probe_addrs[(ioidx)] )
  52
  53 static void isabus_remove ( struct root_device *rootdev );
  54
  55 /**
  56  * Probe an ISA device
  57  *
  58  * @v isa               ISA device
  59  * @ret rc              Return status code
  60  */
  61 static int isa_probe ( struct isa_device *isa ) {
  62         int rc;
  63
  64         DBG ( "Trying ISA driver %s at I/O %04x\n",
  65               isa->driver->name, isa->ioaddr );
  66
  67         if ( ( rc = isa->driver->probe ( isa ) ) != 0 ) {
  68                 DBG ( "...probe failed\n" );
  69                 return rc;
  70         }
  71
  72         DBG ( "...device found\n" );
  73         return 0;
  74 }
  75
  76 /**
  77  * Remove an ISA device
  78  *
  79  * @v isa               ISA device
  80  */
  81 static void isa_remove ( struct isa_device *isa ) {
  82         isa->driver->remove ( isa );
  83         DBG ( "Removed ISA%04x\n", isa->ioaddr );
  84 }
  85
  86 /**
  87  * Probe ISA root bus
  88  *
  89  * @v rootdev           ISA bus root device
  90  *
  91  * Scans the ISA bus for devices and registers all devices it can
  92  * find.
  93  */
  94 static int isabus_probe ( struct root_device *rootdev ) {
  95         struct isa_device *isa = NULL;
  96         struct isa_driver *driver;
  97         int ioidx;
  98         int rc;
  99
 100         for_each_table_entry ( driver, ISA_DRIVERS ) {
 101                 for ( ioidx = ISA_IOIDX_MIN ( driver ) ;
 102                       ioidx <= ISA_IOIDX_MAX ( driver ) ; ioidx++ ) {
 103                         /* Allocate struct isa_device */
 104                         if ( ! isa )
 105                                 isa = malloc ( sizeof ( *isa ) );
 106                         if ( ! isa ) {
 107                                 rc = -ENOMEM;
 108                                 goto err;
 109                         }
 110                         memset ( isa, 0, sizeof ( *isa ) );
 111                         isa->driver = driver;
 112                         isa->ioaddr = ISA_IOADDR ( driver, ioidx );
 113
 114                         /* Add to device hierarchy */
 115                         snprintf ( isa->dev.name, sizeof ( isa->dev.name ),
 116                                    "ISA%04x", isa->ioaddr );
 117                         isa->dev.desc.bus_type = BUS_TYPE_ISA;
 118                         isa->dev.desc.vendor = driver->vendor_id;
 119                         isa->dev.desc.device = driver->prod_id;
 120                         isa->dev.parent = &rootdev->dev;
 121                         list_add ( &isa->dev.siblings,
 122                                    &rootdev->dev.children );
 123                         INIT_LIST_HEAD ( &isa->dev.children );
 124
 125                         /* Try probing at this I/O address */
 126                         if ( isa_probe ( isa ) == 0 ) {
 127                                 /* isadev registered, we can drop our ref */
 128                                 isa = NULL;
 129                         } else {
 130                                 /* Not registered; re-use struct */
 131                                 list_del ( &isa->dev.siblings );
 132                         }
 133                 }
 134         }
 135
 136         free ( isa );
 137         return 0;
 138
 139  err:
 140         free ( isa );
 141         isabus_remove ( rootdev );
 142         return rc;
 143 }
 144
 145 /**
 146  * Remove ISA root bus
 147  *
 148  * @v rootdev           ISA bus root device
 149  */
 150 static void isabus_remove ( struct root_device *rootdev ) {
 151         struct isa_device *isa;
 152         struct isa_device *tmp;
 153
 154         list_for_each_entry_safe ( isa, tmp, &rootdev->dev.children,
 155                                    dev.siblings ) {
 156                 isa_remove ( isa );
 157                 list_del ( &isa->dev.siblings );
 158                 free ( isa );
 159         }
 160 }
 161
 162 /** ISA bus root device driver */
 163 static struct root_driver isa_root_driver = {
 164         .probe = isabus_probe,
 165         .remove = isabus_remove,
 166 };
 167
 168 /** ISA bus root device */
 169 struct root_device isa_root_device __root_device = {
 170         .dev = { .name = "ISA" },
 171         .driver = &isa_root_driver,
 172 };