drivers/dio/dio.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Code to support devices on the DIO and DIO-II bus
   3  * Copyright (C) 05/1998 Peter Maydell <pmaydell@chiark.greenend.org.uk>
   4  * Copyright (C) 2004 Jochen Friedrich <jochen@scram.de>
   5  *
   6  * This code has basically these routines at the moment:
   7  * int dio_find(u_int deviceid)
   8  *    Search the list of DIO devices and return the select code
   9  *    of the next unconfigured device found that matches the given device ID.
  10  *    Note that the deviceid parameter should be the encoded ID.
  11  *    This means that framebuffers should pass it as
  12  *    DIO_ENCODE_ID(DIO_ID_FBUFFER,DIO_ID2_TOPCAT)
  13  *    (or whatever); everybody else just uses DIO_ID_FOOBAR.
  14  * unsigned long dio_scodetophysaddr(int scode)
  15  *    Return the physical address corresponding to the given select code.
  16  * int dio_scodetoipl(int scode)
  17  *    Every DIO card has a fixed interrupt priority level. This function
  18  *    returns it, whatever it is.
  19  * const char *dio_scodetoname(int scode)
  20  *    Return a character string describing this board [might be "" if
  21  *    not CONFIG_DIO_CONSTANTS]
  22  * void dio_config_board(int scode)     mark board as configured in the list
  23  * void dio_unconfig_board(int scode)   mark board as no longer configured
  24  *
  25  * This file is based on the way the Amiga port handles Zorro II cards,
  26  * although we aren't so complicated...
  27  */
  28 #include <linux/module.h>
  29 #include <linux/string.h>
  30 #include <linux/types.h>
  31 #include <linux/kernel.h>
  32 #include <linux/init.h>
  33 #include <linux/dio.h>
  34 #include <linux/slab.h>                         /* kmalloc() */
  35 #include <linux/uaccess.h>
  36 #include <asm/io.h>                             /* readb() */
  37
  38 struct dio_bus dio_bus = {
  39         .resources = {
  40                 /* DIO range */
  41                 { .name = "DIO mem", .start = 0x00600000, .end = 0x007fffff },
  42                 /* DIO-II range */
  43                 { .name = "DIO-II mem", .start = 0x01000000, .end = 0x1fffffff }
  44         },
  45         .name = "DIO bus"
  46 };
  47
  48 /* not a real config option yet! */
  49 #define CONFIG_DIO_CONSTANTS
  50
  51 #ifdef CONFIG_DIO_CONSTANTS
  52 /* We associate each numeric ID with an appropriate descriptive string
  53  * using a constant array of these structs.
  54  * FIXME: we should be able to arrange to throw away most of the strings
  55  * using the initdata stuff. Then we wouldn't need to worry about
  56  * carrying them around...
  57  * I think we do this by copying them into newly kmalloc()ed memory and
  58  * marking the names[] array as .initdata ?
  59  */
  60 struct dioname
  61 {
  62         int id;
  63         const char *name;
  64 };
  65
  66 /* useful macro */
  67 #define DIONAME(x) { DIO_ID_##x, DIO_DESC_##x }
  68 #define DIOFBNAME(x) { DIO_ENCODE_ID( DIO_ID_FBUFFER, DIO_ID2_##x), DIO_DESC2_##x }
  69
  70 static struct dioname names[] =
  71 {
  72         DIONAME(DCA0), DIONAME(DCA0REM), DIONAME(DCA1), DIONAME(DCA1REM),
  73         DIONAME(DCM), DIONAME(DCMREM),
  74         DIONAME(LAN),
  75         DIONAME(FHPIB), DIONAME(NHPIB),
  76         DIONAME(SCSI0), DIONAME(SCSI1), DIONAME(SCSI2), DIONAME(SCSI3),
  77         DIONAME(FBUFFER),
  78         DIONAME(PARALLEL), DIONAME(VME), DIONAME(DCL), DIONAME(DCLREM),
  79         DIONAME(MISC0), DIONAME(MISC1), DIONAME(MISC2), DIONAME(MISC3),
  80         DIONAME(MISC4), DIONAME(MISC5), DIONAME(MISC6), DIONAME(MISC7),
  81         DIONAME(MISC8), DIONAME(MISC9), DIONAME(MISC10), DIONAME(MISC11),
  82         DIONAME(MISC12), DIONAME(MISC13),
  83         DIOFBNAME(GATORBOX), DIOFBNAME(TOPCAT), DIOFBNAME(RENAISSANCE),
  84         DIOFBNAME(LRCATSEYE), DIOFBNAME(HRCCATSEYE), DIOFBNAME(HRMCATSEYE),
  85         DIOFBNAME(DAVINCI), DIOFBNAME(XXXCATSEYE), DIOFBNAME(HYPERION),
  86         DIOFBNAME(XGENESIS), DIOFBNAME(TIGER), DIOFBNAME(YGENESIS)
  87 };
  88
  89 #undef DIONAME
  90 #undef DIOFBNAME
  91
  92 static const char *unknowndioname
  93         = "unknown DIO board -- please email <linux-m68k@lists.linux-m68k.org>!";
  94
  95 static const char *dio_getname(int id)
  96 {
  97         /* return pointer to a constant string describing the board with given ID */
  98         unsigned int i;
  99         for (i = 0; i < ARRAY_SIZE(names); i++)
 100                 if (names[i].id == id)
 101                         return names[i].name;
 102
 103         return unknowndioname;
 104 }
 105
 106 #else
 107
 108 static char dio_no_name[] = { 0 };
 109 #define dio_getname(_id)        (dio_no_name)
 110
 111 #endif /* CONFIG_DIO_CONSTANTS */
 112
 113 int __init dio_find(int deviceid)
 114 {
 115         /* Called to find a DIO device before the full bus scan has run.
 116          * Only used by the console driver.
 117          */
 118         int scode, id;
 119         u_char prid, secid, i;
 120
 121         for (scode = 0; scode < DIO_SCMAX; scode++) {
 122                 void *va;
 123                 unsigned long pa;
 124
 125                 if (DIO_SCINHOLE(scode))
 126                         continue;
 127
 128                 pa = dio_scodetophysaddr(scode);
 129
 130                 if (!pa)
 131                         continue;
 132
 133                 if (scode < DIOII_SCBASE)
 134                         va = (void *)(pa + DIO_VIRADDRBASE);
 135                 else
 136                         va = ioremap(pa, PAGE_SIZE);
 137
 138                 if (probe_kernel_read(&i, (unsigned char *)va + DIO_IDOFF, 1)) {
 139                         if (scode >= DIOII_SCBASE)
 140                                 iounmap(va);
 141                         continue;             /* no board present at that select code */
 142                 }
 143
 144                 prid = DIO_ID(va);
 145
 146                 if (DIO_NEEDSSECID(prid)) {
 147                         secid = DIO_SECID(va);
 148                         id = DIO_ENCODE_ID(prid, secid);
 149                 } else
 150                         id = prid;
 151
 152                 if (id == deviceid) {
 153                         if (scode >= DIOII_SCBASE)
 154                                 iounmap(va);
 155                         return scode;
 156                 }
 157         }
 158
 159         return -1;
 160 }
 161
 162 /* This is the function that scans the DIO space and works out what
 163  * hardware is actually present.
 164  */
 165 static int __init dio_init(void)
 166 {
 167         int scode;
 168         int i;
 169         struct dio_dev *dev;
 170         int error;
 171
 172         if (!MACH_IS_HP300)
 173                 return 0;
 174
 175         printk(KERN_INFO "Scanning for DIO devices...\n");
 176
 177         /* Initialize the DIO bus */
 178         INIT_LIST_HEAD(&dio_bus.devices);
 179         dev_set_name(&dio_bus.dev, "dio");
 180         error = device_register(&dio_bus.dev);
 181         if (error) {
 182                 pr_err("DIO: Error registering dio_bus\n");
 183                 return error;
 184         }
 185
 186         /* Request all resources */
 187         dio_bus.num_resources = (hp300_model == HP_320 ? 1 : 2);
 188         for (i = 0; i < dio_bus.num_resources; i++)
 189                 request_resource(&iomem_resource, &dio_bus.resources[i]);
 190
 191         /* Register all devices */
 192         for (scode = 0; scode < DIO_SCMAX; ++scode)
 193         {
 194                 u_char prid, secid = 0;        /* primary, secondary ID bytes */
 195                 u_char *va;
 196                 unsigned long pa;
 197
 198                 if (DIO_SCINHOLE(scode))
 199                         continue;
 200
 201                 pa = dio_scodetophysaddr(scode);
 202
 203                 if (!pa)
 204                         continue;
 205
 206                 if (scode < DIOII_SCBASE)
 207                         va = (void *)(pa + DIO_VIRADDRBASE);
 208                 else
 209                         va = ioremap(pa, PAGE_SIZE);
 210
 211                 if (probe_kernel_read(&i, (unsigned char *)va + DIO_IDOFF, 1)) {
 212                         if (scode >= DIOII_SCBASE)
 213                                 iounmap(va);
 214                         continue;              /* no board present at that select code */
 215                 }
 216
 217                 /* Found a board, allocate it an entry in the list */
 218                 dev = kzalloc(sizeof(struct dio_dev), GFP_KERNEL);
 219                 if (!dev)
 220                         return 0;
 221
 222                 dev->bus = &dio_bus;
 223                 dev->dev.parent = &dio_bus.dev;
 224                 dev->dev.bus = &dio_bus_type;
 225                 dev->scode = scode;
 226                 dev->resource.start = pa;
 227                 dev->resource.end = pa + DIO_SIZE(scode, va);
 228                 dev_set_name(&dev->dev, "%02x", scode);
 229
 230                 /* read the ID byte(s) and encode if necessary. */
 231                 prid = DIO_ID(va);
 232
 233                 if (DIO_NEEDSSECID(prid)) {
 234                         secid = DIO_SECID(va);
 235                         dev->id = DIO_ENCODE_ID(prid, secid);
 236                 } else
 237                         dev->id = prid;
 238
 239                 dev->ipl = DIO_IPL(va);
 240                 strcpy(dev->name,dio_getname(dev->id));
 241                 printk(KERN_INFO "select code %3d: ipl %d: ID %02X", dev->scode, dev->ipl, prid);
 242                 if (DIO_NEEDSSECID(prid))
 243                         printk(":%02X", secid);
 244                 printk(": %s\n", dev->name);
 245
 246                 if (scode >= DIOII_SCBASE)
 247                         iounmap(va);
 248                 error = device_register(&dev->dev);
 249                 if (error) {
 250                         pr_err("DIO: Error registering device %s\n",
 251                                dev->name);
 252                         continue;
 253                 }
 254                 error = dio_create_sysfs_dev_files(dev);
 255                 if (error)
 256                         dev_err(&dev->dev, "Error creating sysfs files\n");
 257         }
 258         return 0;
 259 }
 260
 261 subsys_initcall(dio_init);
 262
 263 /* Bear in mind that this is called in the very early stages of initialisation
 264  * in order to get the address of the serial port for the console...
 265  */
 266 unsigned long dio_scodetophysaddr(int scode)
 267 {
 268         if (scode >= DIOII_SCBASE) {
 269                 return (DIOII_BASE + (scode - 132) * DIOII_DEVSIZE);
 270         } else if (scode > DIO_SCMAX || scode < 0)
 271                 return 0;
 272         else if (DIO_SCINHOLE(scode))
 273                 return 0;
 274
 275         return (DIO_BASE + scode * DIO_DEVSIZE);
 276 }