drivers/tty/hvc/hvc_opal.c

   1 /*
   2  * opal driver interface to hvc_console.c
   3  *
   4  * Copyright 2011 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  *
  20  */
  21
  22 #undef DEBUG
  23
  24 #include <linux/types.h>
  25 #include <linux/init.h>
  26 #include <linux/delay.h>
  27 #include <linux/slab.h>
  28 #include <linux/console.h>
  29 #include <linux/of.h>
  30 #include <linux/of_platform.h>
  31
  32 #include <asm/hvconsole.h>
  33 #include <asm/prom.h>
  34 #include <asm/firmware.h>
  35 #include <asm/hvsi.h>
  36 #include <asm/udbg.h>
  37 #include <asm/opal.h>
  38
  39 #include "hvc_console.h"
  40
  41 static const char hvc_opal_name[] = "hvc_opal";
  42
  43 static struct of_device_id hvc_opal_match[] __devinitdata = {
  44         { .name = "serial", .compatible = "ibm,opal-console-raw" },
  45         { .name = "serial", .compatible = "ibm,opal-console-hvsi" },
  46         { },
  47 };
  48
  49 typedef enum hv_protocol {
  50         HV_PROTOCOL_RAW,
  51         HV_PROTOCOL_HVSI
  52 } hv_protocol_t;
  53
  54 struct hvc_opal_priv {
  55         hv_protocol_t           proto;  /* Raw data or HVSI packets */
  56         struct hvsi_priv        hvsi;   /* HVSI specific data */
  57 };
  58 static struct hvc_opal_priv *hvc_opal_privs[MAX_NR_HVC_CONSOLES];
  59
  60 /* For early boot console */
  61 static struct hvc_opal_priv hvc_opal_boot_priv;
  62 static u32 hvc_opal_boot_termno;
  63
  64 static const struct hv_ops hvc_opal_raw_ops = {
  65         .get_chars = opal_get_chars,
  66         .put_chars = opal_put_chars,
  67         .notifier_add = notifier_add_irq,
  68         .notifier_del = notifier_del_irq,
  69         .notifier_hangup = notifier_hangup_irq,
  70 };
  71
  72 static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
  73 {
  74         struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
  75
  76         if (WARN_ON(!pv))
  77                 return -ENODEV;
  78
  79         return hvsilib_get_chars(&pv->hvsi, buf, count);
  80 }
  81
  82 static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
  83 {
  84         struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
  85
  86         if (WARN_ON(!pv))
  87                 return -ENODEV;
  88
  89         return hvsilib_put_chars(&pv->hvsi, buf, count);
  90 }
  91
  92 static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data)
  93 {
  94         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
  95         int rc;
  96
  97         pr_devel("HVSI@%x: do open !\n", hp->vtermno);
  98
  99         rc = notifier_add_irq(hp, data);
 100         if (rc)
 101                 return rc;
 102
 103         return hvsilib_open(&pv->hvsi, hp);
 104 }
 105
 106 static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data)
 107 {
 108         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 109
 110         pr_devel("HVSI@%x: do close !\n", hp->vtermno);
 111
 112         hvsilib_close(&pv->hvsi, hp);
 113
 114         notifier_del_irq(hp, data);
 115 }
 116
 117 void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data)
 118 {
 119         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 120
 121         pr_devel("HVSI@%x: do hangup !\n", hp->vtermno);
 122
 123         hvsilib_close(&pv->hvsi, hp);
 124
 125         notifier_hangup_irq(hp, data);
 126 }
 127
 128 static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp)
 129 {
 130         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 131
 132         if (!pv)
 133                 return -EINVAL;
 134         return pv->hvsi.mctrl;
 135 }
 136
 137 static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
 138                                 unsigned int clear)
 139 {
 140         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 141
 142         pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
 143                  hp->vtermno, set, clear);
 144
 145         if (set & TIOCM_DTR)
 146                 hvsilib_write_mctrl(&pv->hvsi, 1);
 147         else if (clear & TIOCM_DTR)
 148                 hvsilib_write_mctrl(&pv->hvsi, 0);
 149
 150         return 0;
 151 }
 152
 153 static const struct hv_ops hvc_opal_hvsi_ops = {
 154         .get_chars = hvc_opal_hvsi_get_chars,
 155         .put_chars = hvc_opal_hvsi_put_chars,
 156         .notifier_add = hvc_opal_hvsi_open,
 157         .notifier_del = hvc_opal_hvsi_close,
 158         .notifier_hangup = hvc_opal_hvsi_hangup,
 159         .tiocmget = hvc_opal_hvsi_tiocmget,
 160         .tiocmset = hvc_opal_hvsi_tiocmset,
 161 };
 162
 163 static int __devinit hvc_opal_probe(struct platform_device *dev)
 164 {
 165         const struct hv_ops *ops;
 166         struct hvc_struct *hp;
 167         struct hvc_opal_priv *pv;
 168         hv_protocol_t proto;
 169         unsigned int termno, boot = 0;
 170         const __be32 *reg;
 171
 172         if (of_device_is_compatible(dev->dev.of_node, "ibm,opal-console-raw")) {
 173                 proto = HV_PROTOCOL_RAW;
 174                 ops = &hvc_opal_raw_ops;
 175         } else if (of_device_is_compatible(dev->dev.of_node,
 176                                            "ibm,opal-console-hvsi")) {
 177                 proto = HV_PROTOCOL_HVSI;
 178                 ops = &hvc_opal_hvsi_ops;
 179         } else {
 180                 pr_err("hvc_opal: Unkown protocol for %s\n",
 181                        dev->dev.of_node->full_name);
 182                 return -ENXIO;
 183         }
 184
 185         reg = of_get_property(dev->dev.of_node, "reg", NULL);
 186         termno = reg ? be32_to_cpup(reg) : 0;
 187
 188         /* Is it our boot one ? */
 189         if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) {
 190                 pv = hvc_opal_privs[termno];
 191                 boot = 1;
 192         } else if (hvc_opal_privs[termno] == NULL) {
 193                 pv = kzalloc(sizeof(struct hvc_opal_priv), GFP_KERNEL);
 194                 if (!pv)
 195                         return -ENOMEM;
 196                 pv->proto = proto;
 197                 hvc_opal_privs[termno] = pv;
 198                 if (proto == HV_PROTOCOL_HVSI)
 199                         hvsilib_init(&pv->hvsi, opal_get_chars, opal_put_chars,
 200                                      termno, 0);
 201
 202                 /* Instanciate now to establish a mapping index==vtermno */
 203                 hvc_instantiate(termno, termno, ops);
 204         } else {
 205                 pr_err("hvc_opal: Device %s has duplicate terminal number #%d\n",
 206                        dev->dev.of_node->full_name, termno);
 207                 return -ENXIO;
 208         }
 209
 210         pr_info("hvc%d: %s protocol on %s%s\n", termno,
 211                 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
 212                 dev->dev.of_node->full_name,
 213                 boot ? " (boot console)" : "");
 214
 215         /* We don't do IRQ yet */
 216         hp = hvc_alloc(termno, 0, ops, MAX_VIO_PUT_CHARS);
 217         if (IS_ERR(hp))
 218                 return PTR_ERR(hp);
 219         dev_set_drvdata(&dev->dev, hp);
 220
 221         return 0;
 222 }
 223
 224 static int __devexit hvc_opal_remove(struct platform_device *dev)
 225 {
 226         struct hvc_struct *hp = dev_get_drvdata(&dev->dev);
 227         int rc, termno;
 228
 229         termno = hp->vtermno;
 230         rc = hvc_remove(hp);
 231         if (rc == 0) {
 232                 if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
 233                         kfree(hvc_opal_privs[termno]);
 234                 hvc_opal_privs[termno] = NULL;
 235         }
 236         return rc;
 237 }
 238
 239 static struct platform_driver hvc_opal_driver = {
 240         .probe          = hvc_opal_probe,
 241         .remove         = __devexit_p(hvc_opal_remove),
 242         .driver         = {
 243                 .name   = hvc_opal_name,
 244                 .owner  = THIS_MODULE,
 245                 .of_match_table = hvc_opal_match,
 246         }
 247 };
 248
 249 static int __init hvc_opal_init(void)
 250 {
 251         if (!firmware_has_feature(FW_FEATURE_OPAL))
 252                 return -ENODEV;
 253
 254         /* Register as a vio device to receive callbacks */
 255         return platform_driver_register(&hvc_opal_driver);
 256 }
 257 module_init(hvc_opal_init);
 258
 259 static void __exit hvc_opal_exit(void)
 260 {
 261         platform_driver_unregister(&hvc_opal_driver);
 262 }
 263 module_exit(hvc_opal_exit);
 264
 265 static void udbg_opal_putc(char c)
 266 {
 267         unsigned int termno = hvc_opal_boot_termno;
 268         int count = -1;
 269
 270         if (c == '\n')
 271                 udbg_opal_putc('\r');
 272
 273         do {
 274                 switch(hvc_opal_boot_priv.proto) {
 275                 case HV_PROTOCOL_RAW:
 276                         count = opal_put_chars(termno, &c, 1);
 277                         break;
 278                 case HV_PROTOCOL_HVSI:
 279                         count = hvc_opal_hvsi_put_chars(termno, &c, 1);
 280                         break;
 281                 }
 282         } while(count == 0 || count == -EAGAIN);
 283 }
 284
 285 static int udbg_opal_getc_poll(void)
 286 {
 287         unsigned int termno = hvc_opal_boot_termno;
 288         int rc = 0;
 289         char c;
 290
 291         switch(hvc_opal_boot_priv.proto) {
 292         case HV_PROTOCOL_RAW:
 293                 rc = opal_get_chars(termno, &c, 1);
 294                 break;
 295         case HV_PROTOCOL_HVSI:
 296                 rc = hvc_opal_hvsi_get_chars(termno, &c, 1);
 297                 break;
 298         }
 299         if (!rc)
 300                 return -1;
 301         return c;
 302 }
 303
 304 static int udbg_opal_getc(void)
 305 {
 306         int ch;
 307         for (;;) {
 308                 ch = udbg_opal_getc_poll();
 309                 if (ch == -1) {
 310                         /* This shouldn't be needed...but... */
 311                         volatile unsigned long delay;
 312                         for (delay=0; delay < 2000000; delay++)
 313                                 ;
 314                 } else {
 315                         return ch;
 316                 }
 317         }
 318 }
 319
 320 static void udbg_init_opal_common(void)
 321 {
 322         udbg_putc = udbg_opal_putc;
 323         udbg_getc = udbg_opal_getc;
 324         udbg_getc_poll = udbg_opal_getc_poll;
 325         tb_ticks_per_usec = 0x200; /* Make udelay not suck */
 326 }
 327
 328 void __init hvc_opal_init_early(void)
 329 {
 330         struct device_node *stdout_node = NULL;
 331         const u32 *termno;
 332         const char *name = NULL;
 333         const struct hv_ops *ops;
 334         u32 index;
 335
 336         /* find the boot console from /chosen/stdout */
 337         if (of_chosen)
 338                 name = of_get_property(of_chosen, "linux,stdout-path", NULL);
 339         if (name) {
 340                 stdout_node = of_find_node_by_path(name);
 341                 if (!stdout_node) {
 342                         pr_err("hvc_opal: Failed to locate default console!\n");
 343                         return;
 344                 }
 345         } else {
 346                 struct device_node *opal, *np;
 347
 348                 /* Current OPAL takeover doesn't provide the stdout
 349                  * path, so we hard wire it
 350                  */
 351                 opal = of_find_node_by_path("/ibm,opal/consoles");
 352                 if (opal)
 353                         pr_devel("hvc_opal: Found consoles in new location\n");
 354                 if (!opal) {
 355                         opal = of_find_node_by_path("/ibm,opal");
 356                         if (opal)
 357                                 pr_devel("hvc_opal: "
 358                                          "Found consoles in old location\n");
 359                 }
 360                 if (!opal)
 361                         return;
 362                 for_each_child_of_node(opal, np) {
 363                         if (!strcmp(np->name, "serial")) {
 364                                 stdout_node = np;
 365                                 break;
 366                         }
 367                 }
 368                 of_node_put(opal);
 369         }
 370         if (!stdout_node)
 371                 return;
 372         termno = of_get_property(stdout_node, "reg", NULL);
 373         index = termno ? *termno : 0;
 374         if (index >= MAX_NR_HVC_CONSOLES)
 375                 return;
 376         hvc_opal_privs[index] = &hvc_opal_boot_priv;
 377
 378         /* Check the protocol */
 379         if (of_device_is_compatible(stdout_node, "ibm,opal-console-raw")) {
 380                 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
 381                 ops = &hvc_opal_raw_ops;
 382                 pr_devel("hvc_opal: Found RAW console\n");
 383         }
 384         else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) {
 385                 hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI;
 386                 ops = &hvc_opal_hvsi_ops;
 387                 hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars,
 388                              opal_put_chars, index, 1);
 389                 /* HVSI, perform the handshake now */
 390                 hvsilib_establish(&hvc_opal_boot_priv.hvsi);
 391                 pr_devel("hvc_opal: Found HVSI console\n");
 392         } else
 393                 goto out;
 394         hvc_opal_boot_termno = index;
 395         udbg_init_opal_common();
 396         add_preferred_console("hvc", index, NULL);
 397         hvc_instantiate(index, index, ops);
 398 out:
 399         of_node_put(stdout_node);
 400 }
 401
 402 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW
 403 void __init udbg_init_debug_opal(void)
 404 {
 405         u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
 406         hvc_opal_privs[index] = &hvc_opal_boot_priv;
 407         hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
 408         hvc_opal_boot_termno = index;
 409         udbg_init_opal_common();
 410 }
 411 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */
 412
 413 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI
 414 void __init udbg_init_debug_opal_hvsi(void)
 415 {
 416         u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
 417         hvc_opal_privs[index] = &hvc_opal_boot_priv;
 418         hvc_opal_boot_termno = index;
 419         udbg_init_opal_common();
 420         hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, opal_put_chars,
 421                      index, 1);
 422         hvsilib_establish(&hvc_opal_boot_priv.hvsi);
 423 }
 424 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */