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 #include <linux/interrupt.h>
  33
  34 #include <asm/hvconsole.h>
  35 #include <asm/prom.h>
  36 #include <asm/firmware.h>
  37 #include <asm/hvsi.h>
  38 #include <asm/udbg.h>
  39 #include <asm/opal.h>
  40
  41 #include "hvc_console.h"
  42
  43 static const char hvc_opal_name[] = "hvc_opal";
  44
  45 static const struct of_device_id hvc_opal_match[] = {
  46         { .name = "serial", .compatible = "ibm,opal-console-raw" },
  47         { .name = "serial", .compatible = "ibm,opal-console-hvsi" },
  48         { },
  49 };
  50
  51 typedef enum hv_protocol {
  52         HV_PROTOCOL_RAW,
  53         HV_PROTOCOL_HVSI
  54 } hv_protocol_t;
  55
  56 struct hvc_opal_priv {
  57         hv_protocol_t           proto;  /* Raw data or HVSI packets */
  58         struct hvsi_priv        hvsi;   /* HVSI specific data */
  59 };
  60 static struct hvc_opal_priv *hvc_opal_privs[MAX_NR_HVC_CONSOLES];
  61
  62 /* For early boot console */
  63 static struct hvc_opal_priv hvc_opal_boot_priv;
  64 static u32 hvc_opal_boot_termno;
  65
  66 static const struct hv_ops hvc_opal_raw_ops = {
  67         .get_chars = opal_get_chars,
  68         .put_chars = opal_put_chars,
  69         .notifier_add = notifier_add_irq,
  70         .notifier_del = notifier_del_irq,
  71         .notifier_hangup = notifier_hangup_irq,
  72 };
  73
  74 static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
  75 {
  76         struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
  77
  78         if (WARN_ON(!pv))
  79                 return -ENODEV;
  80
  81         return hvsilib_get_chars(&pv->hvsi, buf, count);
  82 }
  83
  84 static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
  85 {
  86         struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
  87
  88         if (WARN_ON(!pv))
  89                 return -ENODEV;
  90
  91         return hvsilib_put_chars(&pv->hvsi, buf, count);
  92 }
  93
  94 static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data)
  95 {
  96         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
  97         int rc;
  98
  99         pr_devel("HVSI@%x: do open !\n", hp->vtermno);
 100
 101         rc = notifier_add_irq(hp, data);
 102         if (rc)
 103                 return rc;
 104
 105         return hvsilib_open(&pv->hvsi, hp);
 106 }
 107
 108 static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data)
 109 {
 110         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 111
 112         pr_devel("HVSI@%x: do close !\n", hp->vtermno);
 113
 114         hvsilib_close(&pv->hvsi, hp);
 115
 116         notifier_del_irq(hp, data);
 117 }
 118
 119 void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data)
 120 {
 121         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 122
 123         pr_devel("HVSI@%x: do hangup !\n", hp->vtermno);
 124
 125         hvsilib_close(&pv->hvsi, hp);
 126
 127         notifier_hangup_irq(hp, data);
 128 }
 129
 130 static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp)
 131 {
 132         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 133
 134         if (!pv)
 135                 return -EINVAL;
 136         return pv->hvsi.mctrl;
 137 }
 138
 139 static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
 140                                 unsigned int clear)
 141 {
 142         struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
 143
 144         pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
 145                  hp->vtermno, set, clear);
 146
 147         if (set & TIOCM_DTR)
 148                 hvsilib_write_mctrl(&pv->hvsi, 1);
 149         else if (clear & TIOCM_DTR)
 150                 hvsilib_write_mctrl(&pv->hvsi, 0);
 151
 152         return 0;
 153 }
 154
 155 static const struct hv_ops hvc_opal_hvsi_ops = {
 156         .get_chars = hvc_opal_hvsi_get_chars,
 157         .put_chars = hvc_opal_hvsi_put_chars,
 158         .notifier_add = hvc_opal_hvsi_open,
 159         .notifier_del = hvc_opal_hvsi_close,
 160         .notifier_hangup = hvc_opal_hvsi_hangup,
 161         .tiocmget = hvc_opal_hvsi_tiocmget,
 162         .tiocmset = hvc_opal_hvsi_tiocmset,
 163 };
 164
 165 static int hvc_opal_probe(struct platform_device *dev)
 166 {
 167         const struct hv_ops *ops;
 168         struct hvc_struct *hp;
 169         struct hvc_opal_priv *pv;
 170         hv_protocol_t proto;
 171         unsigned int termno, irq, boot = 0;
 172         const __be32 *reg;
 173
 174         if (of_device_is_compatible(dev->dev.of_node, "ibm,opal-console-raw")) {
 175                 proto = HV_PROTOCOL_RAW;
 176                 ops = &hvc_opal_raw_ops;
 177         } else if (of_device_is_compatible(dev->dev.of_node,
 178                                            "ibm,opal-console-hvsi")) {
 179                 proto = HV_PROTOCOL_HVSI;
 180                 ops = &hvc_opal_hvsi_ops;
 181         } else {
 182                 pr_err("hvc_opal: Unknown protocol for %pOF\n",
 183                        dev->dev.of_node);
 184                 return -ENXIO;
 185         }
 186
 187         reg = of_get_property(dev->dev.of_node, "reg", NULL);
 188         termno = reg ? be32_to_cpup(reg) : 0;
 189
 190         /* Is it our boot one ? */
 191         if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) {
 192                 pv = hvc_opal_privs[termno];
 193                 boot = 1;
 194         } else if (hvc_opal_privs[termno] == NULL) {
 195                 pv = kzalloc(sizeof(struct hvc_opal_priv), GFP_KERNEL);
 196                 if (!pv)
 197                         return -ENOMEM;
 198                 pv->proto = proto;
 199                 hvc_opal_privs[termno] = pv;
 200                 if (proto == HV_PROTOCOL_HVSI)
 201                         hvsilib_init(&pv->hvsi, opal_get_chars, opal_put_chars,
 202                                      termno, 0);
 203
 204                 /* Instanciate now to establish a mapping index==vtermno */
 205                 hvc_instantiate(termno, termno, ops);
 206         } else {
 207                 pr_err("hvc_opal: Device %pOF has duplicate terminal number #%d\n",
 208                        dev->dev.of_node, termno);
 209                 return -ENXIO;
 210         }
 211
 212         pr_info("hvc%d: %s protocol on %pOF%s\n", termno,
 213                 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
 214                 dev->dev.of_node,
 215                 boot ? " (boot console)" : "");
 216
 217         irq = irq_of_parse_and_map(dev->dev.of_node, 0);
 218         if (!irq) {
 219                 pr_info("hvc%d: No interrupts property, using OPAL event\n",
 220                                 termno);
 221                 irq = opal_event_request(ilog2(OPAL_EVENT_CONSOLE_INPUT));
 222         }
 223
 224         if (!irq) {
 225                 pr_err("hvc_opal: Unable to map interrupt for device %pOF\n",
 226                         dev->dev.of_node);
 227                 return irq;
 228         }
 229
 230         hp = hvc_alloc(termno, irq, ops, MAX_VIO_PUT_CHARS);
 231         if (IS_ERR(hp))
 232                 return PTR_ERR(hp);
 233
 234         /* hvc consoles on powernv may need to share a single irq */
 235         hp->flags = IRQF_SHARED;
 236         dev_set_drvdata(&dev->dev, hp);
 237
 238         return 0;
 239 }
 240
 241 static int hvc_opal_remove(struct platform_device *dev)
 242 {
 243         struct hvc_struct *hp = dev_get_drvdata(&dev->dev);
 244         int rc, termno;
 245
 246         termno = hp->vtermno;
 247         rc = hvc_remove(hp);
 248         if (rc == 0) {
 249                 if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
 250                         kfree(hvc_opal_privs[termno]);
 251                 hvc_opal_privs[termno] = NULL;
 252         }
 253         return rc;
 254 }
 255
 256 static struct platform_driver hvc_opal_driver = {
 257         .probe          = hvc_opal_probe,
 258         .remove         = hvc_opal_remove,
 259         .driver         = {
 260                 .name   = hvc_opal_name,
 261                 .of_match_table = hvc_opal_match,
 262         }
 263 };
 264
 265 static int __init hvc_opal_init(void)
 266 {
 267         if (!firmware_has_feature(FW_FEATURE_OPAL))
 268                 return -ENODEV;
 269
 270         /* Register as a vio device to receive callbacks */
 271         return platform_driver_register(&hvc_opal_driver);
 272 }
 273 device_initcall(hvc_opal_init);
 274
 275 static void udbg_opal_putc(char c)
 276 {
 277         unsigned int termno = hvc_opal_boot_termno;
 278         int count = -1;
 279
 280         if (c == '\n')
 281                 udbg_opal_putc('\r');
 282
 283         do {
 284                 switch(hvc_opal_boot_priv.proto) {
 285                 case HV_PROTOCOL_RAW:
 286                         count = opal_put_chars(termno, &c, 1);
 287                         break;
 288                 case HV_PROTOCOL_HVSI:
 289                         count = hvc_opal_hvsi_put_chars(termno, &c, 1);
 290                         break;
 291                 }
 292         } while(count == 0 || count == -EAGAIN);
 293 }
 294
 295 static int udbg_opal_getc_poll(void)
 296 {
 297         unsigned int termno = hvc_opal_boot_termno;
 298         int rc = 0;
 299         char c;
 300
 301         switch(hvc_opal_boot_priv.proto) {
 302         case HV_PROTOCOL_RAW:
 303                 rc = opal_get_chars(termno, &c, 1);
 304                 break;
 305         case HV_PROTOCOL_HVSI:
 306                 rc = hvc_opal_hvsi_get_chars(termno, &c, 1);
 307                 break;
 308         }
 309         if (!rc)
 310                 return -1;
 311         return c;
 312 }
 313
 314 static int udbg_opal_getc(void)
 315 {
 316         int ch;
 317         for (;;) {
 318                 ch = udbg_opal_getc_poll();
 319                 if (ch == -1) {
 320                         /* This shouldn't be needed...but... */
 321                         volatile unsigned long delay;
 322                         for (delay=0; delay < 2000000; delay++)
 323                                 ;
 324                 } else {
 325                         return ch;
 326                 }
 327         }
 328 }
 329
 330 static void udbg_init_opal_common(void)
 331 {
 332         udbg_putc = udbg_opal_putc;
 333         udbg_getc = udbg_opal_getc;
 334         udbg_getc_poll = udbg_opal_getc_poll;
 335 }
 336
 337 void __init hvc_opal_init_early(void)
 338 {
 339         struct device_node *stdout_node = of_node_get(of_stdout);
 340         const __be32 *termno;
 341         const struct hv_ops *ops;
 342         u32 index;
 343
 344         /* If the console wasn't in /chosen, try /ibm,opal */
 345         if (!stdout_node) {
 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 ? be32_to_cpup(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_raw(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 */