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 device_initcall(hvc_opal_init);
 259
 260 static void udbg_opal_putc(char c)
 261 {
 262         unsigned int termno = hvc_opal_boot_termno;
 263         int count = -1;
 264
 265         if (c == '\n')
 266                 udbg_opal_putc('\r');
 267
 268         do {
 269                 switch(hvc_opal_boot_priv.proto) {
 270                 case HV_PROTOCOL_RAW:
 271                         count = opal_put_chars(termno, &c, 1);
 272                         break;
 273                 case HV_PROTOCOL_HVSI:
 274                         count = hvc_opal_hvsi_put_chars(termno, &c, 1);
 275                         break;
 276                 }
 277         } while(count == 0 || count == -EAGAIN);
 278 }
 279
 280 static int udbg_opal_getc_poll(void)
 281 {
 282         unsigned int termno = hvc_opal_boot_termno;
 283         int rc = 0;
 284         char c;
 285
 286         switch(hvc_opal_boot_priv.proto) {
 287         case HV_PROTOCOL_RAW:
 288                 rc = opal_get_chars(termno, &c, 1);
 289                 break;
 290         case HV_PROTOCOL_HVSI:
 291                 rc = hvc_opal_hvsi_get_chars(termno, &c, 1);
 292                 break;
 293         }
 294         if (!rc)
 295                 return -1;
 296         return c;
 297 }
 298
 299 static int udbg_opal_getc(void)
 300 {
 301         int ch;
 302         for (;;) {
 303                 ch = udbg_opal_getc_poll();
 304                 if (ch == -1) {
 305                         /* This shouldn't be needed...but... */
 306                         volatile unsigned long delay;
 307                         for (delay=0; delay < 2000000; delay++)
 308                                 ;
 309                 } else {
 310                         return ch;
 311                 }
 312         }
 313 }
 314
 315 static void udbg_init_opal_common(void)
 316 {
 317         udbg_putc = udbg_opal_putc;
 318         udbg_getc = udbg_opal_getc;
 319         udbg_getc_poll = udbg_opal_getc_poll;
 320         tb_ticks_per_usec = 0x200; /* Make udelay not suck */
 321 }
 322
 323 void __init hvc_opal_init_early(void)
 324 {
 325         struct device_node *stdout_node = NULL;
 326         const __be32 *termno;
 327         const char *name = NULL;
 328         const struct hv_ops *ops;
 329         u32 index;
 330
 331         /* find the boot console from /chosen/stdout */
 332         if (of_chosen)
 333                 name = of_get_property(of_chosen, "linux,stdout-path", NULL);
 334         if (name) {
 335                 stdout_node = of_find_node_by_path(name);
 336                 if (!stdout_node) {
 337                         pr_err("hvc_opal: Failed to locate default console!\n");
 338                         return;
 339                 }
 340         } else {
 341                 struct device_node *opal, *np;
 342
 343                 /* Current OPAL takeover doesn't provide the stdout
 344                  * path, so we hard wire it
 345                  */
 346                 opal = of_find_node_by_path("/ibm,opal/consoles");
 347                 if (opal)
 348                         pr_devel("hvc_opal: Found consoles in new location\n");
 349                 if (!opal) {
 350                         opal = of_find_node_by_path("/ibm,opal");
 351                         if (opal)
 352                                 pr_devel("hvc_opal: "
 353                                          "Found consoles in old location\n");
 354                 }
 355                 if (!opal)
 356                         return;
 357                 for_each_child_of_node(opal, np) {
 358                         if (!strcmp(np->name, "serial")) {
 359                                 stdout_node = np;
 360                                 break;
 361                         }
 362                 }
 363                 of_node_put(opal);
 364         }
 365         if (!stdout_node)
 366                 return;
 367         termno = of_get_property(stdout_node, "reg", NULL);
 368         index = termno ? be32_to_cpup(termno) : 0;
 369         if (index >= MAX_NR_HVC_CONSOLES)
 370                 return;
 371         hvc_opal_privs[index] = &hvc_opal_boot_priv;
 372
 373         /* Check the protocol */
 374         if (of_device_is_compatible(stdout_node, "ibm,opal-console-raw")) {
 375                 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
 376                 ops = &hvc_opal_raw_ops;
 377                 pr_devel("hvc_opal: Found RAW console\n");
 378         }
 379         else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) {
 380                 hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI;
 381                 ops = &hvc_opal_hvsi_ops;
 382                 hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars,
 383                              opal_put_chars, index, 1);
 384                 /* HVSI, perform the handshake now */
 385                 hvsilib_establish(&hvc_opal_boot_priv.hvsi);
 386                 pr_devel("hvc_opal: Found HVSI console\n");
 387         } else
 388                 goto out;
 389         hvc_opal_boot_termno = index;
 390         udbg_init_opal_common();
 391         add_preferred_console("hvc", index, NULL);
 392         hvc_instantiate(index, index, ops);
 393 out:
 394         of_node_put(stdout_node);
 395 }
 396
 397 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW
 398 void __init udbg_init_debug_opal_raw(void)
 399 {
 400         u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
 401         hvc_opal_privs[index] = &hvc_opal_boot_priv;
 402         hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
 403         hvc_opal_boot_termno = index;
 404         udbg_init_opal_common();
 405 }
 406 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */
 407
 408 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI
 409 void __init udbg_init_debug_opal_hvsi(void)
 410 {
 411         u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
 412         hvc_opal_privs[index] = &hvc_opal_boot_priv;
 413         hvc_opal_boot_termno = index;
 414         udbg_init_opal_common();
 415         hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, opal_put_chars,
 416                      index, 1);
 417         hvsilib_establish(&hvc_opal_boot_priv.hvsi);
 418 }
 419 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */