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 <linux/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         int id;
  62         const char *name;
  63 };
  64
  65 /* useful macro */
  66 #define DIONAME(x) { DIO_ID_##x, DIO_DESC_##x }
  67 #define DIOFBNAME(x) { DIO_ENCODE_ID(DIO_ID_FBUFFER, DIO_ID2_##x), DIO_DESC2_##x }
  68
  69 static struct dioname names[] = {
  70         DIONAME(DCA0), DIONAME(DCA0REM), DIONAME(DCA1), DIONAME(DCA1REM),
  71         DIONAME(DCM), DIONAME(DCMREM),
  72         DIONAME(LAN),
  73         DIONAME(FHPIB), DIONAME(NHPIB),
  74         DIONAME(SCSI0), DIONAME(SCSI1), DIONAME(SCSI2), DIONAME(SCSI3),
  75         DIONAME(FBUFFER),
  76         DIONAME(PARALLEL), DIONAME(VME), DIONAME(DCL), DIONAME(DCLREM),
  77         DIONAME(MISC0), DIONAME(MISC1), DIONAME(MISC2), DIONAME(MISC3),
  78         DIONAME(MISC4), DIONAME(MISC5), DIONAME(MISC6), DIONAME(MISC7),
  79         DIONAME(MISC8), DIONAME(MISC9), DIONAME(MISC10), DIONAME(MISC11),
  80         DIONAME(MISC12), DIONAME(MISC13),
  81         DIOFBNAME(GATORBOX), DIOFBNAME(TOPCAT), DIOFBNAME(RENAISSANCE),
  82         DIOFBNAME(LRCATSEYE), DIOFBNAME(HRCCATSEYE), DIOFBNAME(HRMCATSEYE),
  83         DIOFBNAME(DAVINCI), DIOFBNAME(XXXCATSEYE), DIOFBNAME(HYPERION),
  84         DIOFBNAME(XGENESIS), DIOFBNAME(TIGER), DIOFBNAME(YGENESIS)
  85 };
  86
  87 #undef DIONAME
  88 #undef DIOFBNAME
  89
  90 static const char unknowndioname[]
  91         = "unknown DIO board, please email linux-m68k@lists.linux-m68k.org";
  92
  93 static const char *dio_getname(int id)
  94 {
  95         /* return pointer to a constant string describing the board with given ID */
  96         unsigned int i;
  97
  98         for (i = 0; i < ARRAY_SIZE(names); i++)
  99                 if (names[i].id == id)
 100                         return names[i].name;
 101
 102         return unknowndioname;
 103 }
 104
 105 #else
 106
 107 static char dio_no_name[] = { 0 };
 108 #define dio_getname(_id)        (dio_no_name)
 109
 110 #endif /* CONFIG_DIO_CONSTANTS */
 111
 112 static void dio_dev_release(struct device *dev)
 113 {
 114         struct dio_dev *ddev = container_of(dev, typeof(struct dio_dev), dev);
 115         kfree(ddev);
 116 }
 117
 118 int __init dio_find(int deviceid)
 119 {
 120         /* Called to find a DIO device before the full bus scan has run.
 121          * Only used by the console driver.
 122          */
 123         int scode, id;
 124         u_char prid, secid, i;
 125
 126         for (scode = 0; scode < DIO_SCMAX; scode++) {
 127                 void *va;
 128                 unsigned long pa;
 129
 130                 if (DIO_SCINHOLE(scode))
 131                         continue;
 132
 133                 pa = dio_scodetophysaddr(scode);
 134
 135                 if (!pa)
 136                         continue;
 137
 138                 if (scode < DIOII_SCBASE)
 139                         va = (void *)(pa + DIO_VIRADDRBASE);
 140                 else
 141                         va = ioremap(pa, PAGE_SIZE);
 142
 143                 if (copy_from_kernel_nofault(&i,
 144                                 (unsigned char *)va + DIO_IDOFF, 1)) {
 145                         if (scode >= DIOII_SCBASE)
 146                                 iounmap(va);
 147                         continue;            /* no board present at that select code */
 148                 }
 149
 150                 prid = DIO_ID(va);
 151
 152                 if (DIO_NEEDSSECID(prid)) {
 153                         secid = DIO_SECID(va);
 154                         id = DIO_ENCODE_ID(prid, secid);
 155                 } else
 156                         id = prid;
 157
 158                 if (id == deviceid) {
 159                         if (scode >= DIOII_SCBASE)
 160                                 iounmap(va);
 161                         return scode;
 162                 }
 163         }
 164
 165         return -1;
 166 }
 167
 168 /* This is the function that scans the DIO space and works out what
 169  * hardware is actually present.
 170  */
 171 static int __init dio_init(void)
 172 {
 173         int scode;
 174         int i;
 175         struct dio_dev *dev;
 176         int error;
 177
 178         if (!MACH_IS_HP300)
 179                 return 0;
 180
 181         printk(KERN_INFO "Scanning for DIO devices...\n");
 182
 183         /* Initialize the DIO bus */
 184         INIT_LIST_HEAD(&dio_bus.devices);
 185         dev_set_name(&dio_bus.dev, "dio");
 186         error = device_register(&dio_bus.dev);
 187         if (error) {
 188                 pr_err("DIO: Error registering dio_bus\n");
 189                 return error;
 190         }
 191
 192         /* Request all resources */
 193         dio_bus.num_resources = (hp300_model == HP_320 ? 1 : 2);
 194         for (i = 0; i < dio_bus.num_resources; i++)
 195                 request_resource(&iomem_resource, &dio_bus.resources[i]);
 196
 197         /* Register all devices */
 198         for (scode = 0; scode < DIO_SCMAX; ++scode) {
 199                 u_char prid, secid = 0; /* primary, secondary ID bytes */
 200                 u_char *va;
 201                 unsigned long pa;
 202
 203                 if (DIO_SCINHOLE(scode))
 204                         continue;
 205
 206                 pa = dio_scodetophysaddr(scode);
 207
 208                 if (!pa)
 209                         continue;
 210
 211                 if (scode < DIOII_SCBASE)
 212                         va = (void *)(pa + DIO_VIRADDRBASE);
 213                 else
 214                         va = ioremap(pa, PAGE_SIZE);
 215
 216                 if (copy_from_kernel_nofault(&i,
 217                                 (unsigned char *)va + DIO_IDOFF, 1)) {
 218                         if (scode >= DIOII_SCBASE)
 219                                 iounmap(va);
 220                         continue;             /* no board present at that select code */
 221                 }
 222
 223                 /* Found a board, allocate it an entry in the list */
 224                 dev = kzalloc(sizeof(struct dio_dev), GFP_KERNEL);
 225                 if (!dev) {
 226                         if (scode >= DIOII_SCBASE)
 227                                 iounmap(va);
 228                         return -ENOMEM;
 229                 }
 230
 231                 dev->bus = &dio_bus;
 232                 dev->dev.parent = &dio_bus.dev;
 233                 dev->dev.bus = &dio_bus_type;
 234                 dev->dev.release = dio_dev_release;
 235                 dev->scode = scode;
 236                 dev->resource.start = pa;
 237                 dev->resource.end = pa + DIO_SIZE(scode, va);
 238                 dev_set_name(&dev->dev, "%02x", scode);
 239
 240                 /* read the ID byte(s) and encode if necessary. */
 241                 prid = DIO_ID(va);
 242
 243                 if (DIO_NEEDSSECID(prid)) {
 244                         secid = DIO_SECID(va);
 245                         dev->id = DIO_ENCODE_ID(prid, secid);
 246                 } else
 247                         dev->id = prid;
 248
 249                 dev->ipl = DIO_IPL(va);
 250                 strcpy(dev->name, dio_getname(dev->id));
 251                 printk(KERN_INFO "select code %3d: ipl %d: ID %02X", dev->scode, dev->ipl, prid);
 252                 if (DIO_NEEDSSECID(prid))
 253                         printk(":%02X", secid);
 254                 printk(": %s\n", dev->name);
 255
 256                 if (scode >= DIOII_SCBASE)
 257                         iounmap(va);
 258                 error = device_register(&dev->dev);
 259                 if (error) {
 260                         pr_err("DIO: Error registering device %s\n",
 261                                dev->name);
 262                         put_device(&dev->dev);
 263                         continue;
 264                 }
 265                 error = dio_create_sysfs_dev_files(dev);
 266                 if (error)
 267                         dev_err(&dev->dev, "Error creating sysfs files\n");
 268         }
 269         return 0;
 270 }
 271
 272 subsys_initcall(dio_init);
 273
 274 /* Bear in mind that this is called in the very early stages of initialisation
 275  * in order to get the address of the serial port for the console...
 276  */
 277 unsigned long dio_scodetophysaddr(int scode)
 278 {
 279         if (scode >= DIOII_SCBASE)
 280                 return (DIOII_BASE + (scode - 132) * DIOII_DEVSIZE);
 281         else if (scode > DIO_SCMAX || scode < 0)
 282                 return 0;
 283         else if (DIO_SCINHOLE(scode))
 284                 return 0;
 285
 286         return (DIO_BASE + scode * DIO_DEVSIZE);
 287 }