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