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 (copy_from_kernel_nofault(&i,
 139                                 (unsigned char *)va + DIO_IDOFF, 1)) {
 140                         if (scode >= DIOII_SCBASE)
 141                                 iounmap(va);
 142                         continue;             /* no board present at that select code */
 143                 }
 144
 145                 prid = DIO_ID(va);
 146
 147                 if (DIO_NEEDSSECID(prid)) {
 148                         secid = DIO_SECID(va);
 149                         id = DIO_ENCODE_ID(prid, secid);
 150                 } else
 151                         id = prid;
 152
 153                 if (id == deviceid) {
 154                         if (scode >= DIOII_SCBASE)
 155                                 iounmap(va);
 156                         return scode;
 157                 }
 158         }
 159
 160         return -1;
 161 }
 162
 163 /* This is the function that scans the DIO space and works out what
 164  * hardware is actually present.
 165  */
 166 static int __init dio_init(void)
 167 {
 168         int scode;
 169         int i;
 170         struct dio_dev *dev;
 171         int error;
 172
 173         if (!MACH_IS_HP300)
 174                 return 0;
 175
 176         printk(KERN_INFO "Scanning for DIO devices...\n");
 177
 178         /* Initialize the DIO bus */
 179         INIT_LIST_HEAD(&dio_bus.devices);
 180         dev_set_name(&dio_bus.dev, "dio");
 181         error = device_register(&dio_bus.dev);
 182         if (error) {
 183                 pr_err("DIO: Error registering dio_bus\n");
 184                 return error;
 185         }
 186
 187         /* Request all resources */
 188         dio_bus.num_resources = (hp300_model == HP_320 ? 1 : 2);
 189         for (i = 0; i < dio_bus.num_resources; i++)
 190                 request_resource(&iomem_resource, &dio_bus.resources[i]);
 191
 192         /* Register all devices */
 193         for (scode = 0; scode < DIO_SCMAX; ++scode)
 194         {
 195                 u_char prid, secid = 0;        /* primary, secondary ID bytes */
 196                 u_char *va;
 197                 unsigned long pa;
 198
 199                 if (DIO_SCINHOLE(scode))
 200                         continue;
 201
 202                 pa = dio_scodetophysaddr(scode);
 203
 204                 if (!pa)
 205                         continue;
 206
 207                 if (scode < DIOII_SCBASE)
 208                         va = (void *)(pa + DIO_VIRADDRBASE);
 209                 else
 210                         va = ioremap(pa, PAGE_SIZE);
 211
 212                 if (copy_from_kernel_nofault(&i,
 213                                 (unsigned char *)va + DIO_IDOFF, 1)) {
 214                         if (scode >= DIOII_SCBASE)
 215                                 iounmap(va);
 216                         continue;              /* no board present at that select code */
 217                 }
 218
 219                 /* Found a board, allocate it an entry in the list */
 220                 dev = kzalloc(sizeof(struct dio_dev), GFP_KERNEL);
 221                 if (!dev)
 222                         return 0;
 223
 224                 dev->bus = &dio_bus;
 225                 dev->dev.parent = &dio_bus.dev;
 226                 dev->dev.bus = &dio_bus_type;
 227                 dev->scode = scode;
 228                 dev->resource.start = pa;
 229                 dev->resource.end = pa + DIO_SIZE(scode, va);
 230                 dev_set_name(&dev->dev, "%02x", scode);
 231
 232                 /* read the ID byte(s) and encode if necessary. */
 233                 prid = DIO_ID(va);
 234
 235                 if (DIO_NEEDSSECID(prid)) {
 236                         secid = DIO_SECID(va);
 237                         dev->id = DIO_ENCODE_ID(prid, secid);
 238                 } else
 239                         dev->id = prid;
 240
 241                 dev->ipl = DIO_IPL(va);
 242                 strcpy(dev->name,dio_getname(dev->id));
 243                 printk(KERN_INFO "select code %3d: ipl %d: ID %02X", dev->scode, dev->ipl, prid);
 244                 if (DIO_NEEDSSECID(prid))
 245                         printk(":%02X", secid);
 246                 printk(": %s\n", dev->name);
 247
 248                 if (scode >= DIOII_SCBASE)
 249                         iounmap(va);
 250                 error = device_register(&dev->dev);
 251                 if (error) {
 252                         pr_err("DIO: Error registering device %s\n",
 253                                dev->name);
 254                         continue;
 255                 }
 256                 error = dio_create_sysfs_dev_files(dev);
 257                 if (error)
 258                         dev_err(&dev->dev, "Error creating sysfs files\n");
 259         }
 260         return 0;
 261 }
 262
 263 subsys_initcall(dio_init);
 264
 265 /* Bear in mind that this is called in the very early stages of initialisation
 266  * in order to get the address of the serial port for the console...
 267  */
 268 unsigned long dio_scodetophysaddr(int scode)
 269 {
 270         if (scode >= DIOII_SCBASE) {
 271                 return (DIOII_BASE + (scode - 132) * DIOII_DEVSIZE);
 272         } else if (scode > DIO_SCMAX || scode < 0)
 273                 return 0;
 274         else if (DIO_SCINHOLE(scode))
 275                 return 0;
 276
 277         return (DIO_BASE + scode * DIO_DEVSIZE);
 278 }