arch/powerpc/platforms/powernv/opal.c

   1 /*
   2  * PowerNV OPAL high level interfaces
   3  *
   4  * Copyright 2011 IBM Corp.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #undef DEBUG
  13
  14 #include <linux/types.h>
  15 #include <linux/of.h>
  16 #include <linux/of_platform.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/notifier.h>
  19 #include <linux/slab.h>
  20 #include <asm/opal.h>
  21 #include <asm/firmware.h>
  22
  23 #include "powernv.h"
  24
  25 struct opal {
  26         u64 base;
  27         u64 entry;
  28 } opal;
  29
  30 static struct device_node *opal_node;
  31 static DEFINE_SPINLOCK(opal_write_lock);
  32 extern u64 opal_mc_secondary_handler[];
  33 static unsigned int *opal_irqs;
  34 static unsigned int opal_irq_count;
  35 static ATOMIC_NOTIFIER_HEAD(opal_notifier_head);
  36 static DEFINE_SPINLOCK(opal_notifier_lock);
  37 static uint64_t last_notified_mask = 0x0ul;
  38 static atomic_t opal_notifier_hold = ATOMIC_INIT(0);
  39
  40 int __init early_init_dt_scan_opal(unsigned long node,
  41                                    const char *uname, int depth, void *data)
  42 {
  43         const void *basep, *entryp;
  44         unsigned long basesz, entrysz;
  45
  46         if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
  47                 return 0;
  48
  49         basep  = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
  50         entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
  51
  52         if (!basep || !entryp)
  53                 return 1;
  54
  55         opal.base = of_read_number(basep, basesz/4);
  56         opal.entry = of_read_number(entryp, entrysz/4);
  57
  58         pr_debug("OPAL Base  = 0x%llx (basep=%p basesz=%ld)\n",
  59                  opal.base, basep, basesz);
  60         pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%ld)\n",
  61                  opal.entry, entryp, entrysz);
  62
  63         powerpc_firmware_features |= FW_FEATURE_OPAL;
  64         if (of_flat_dt_is_compatible(node, "ibm,opal-v3")) {
  65                 powerpc_firmware_features |= FW_FEATURE_OPALv2;
  66                 powerpc_firmware_features |= FW_FEATURE_OPALv3;
  67                 printk("OPAL V3 detected !\n");
  68         } else if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) {
  69                 powerpc_firmware_features |= FW_FEATURE_OPALv2;
  70                 printk("OPAL V2 detected !\n");
  71         } else {
  72                 printk("OPAL V1 detected !\n");
  73         }
  74
  75         return 1;
  76 }
  77
  78 static int __init opal_register_exception_handlers(void)
  79 {
  80         u64 glue;
  81
  82         if (!(powerpc_firmware_features & FW_FEATURE_OPAL))
  83                 return -ENODEV;
  84
  85         /* Hookup some exception handlers. We use the fwnmi area at 0x7000
  86          * to provide the glue space to OPAL
  87          */
  88         glue = 0x7000;
  89         opal_register_exception_handler(OPAL_MACHINE_CHECK_HANDLER,
  90                                         __pa(opal_mc_secondary_handler[0]),
  91                                         glue);
  92         glue += 128;
  93         opal_register_exception_handler(OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
  94                                         0, glue);
  95         glue += 128;
  96         opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
  97
  98         return 0;
  99 }
 100
 101 early_initcall(opal_register_exception_handlers);
 102
 103 int opal_notifier_register(struct notifier_block *nb)
 104 {
 105         if (!nb) {
 106                 pr_warning("%s: Invalid argument (%p)\n",
 107                            __func__, nb);
 108                 return -EINVAL;
 109         }
 110
 111         atomic_notifier_chain_register(&opal_notifier_head, nb);
 112         return 0;
 113 }
 114
 115 static void opal_do_notifier(uint64_t events)
 116 {
 117         unsigned long flags;
 118         uint64_t changed_mask;
 119
 120         if (atomic_read(&opal_notifier_hold))
 121                 return;
 122
 123         spin_lock_irqsave(&opal_notifier_lock, flags);
 124         changed_mask = last_notified_mask ^ events;
 125         last_notified_mask = events;
 126         spin_unlock_irqrestore(&opal_notifier_lock, flags);
 127
 128         /*
 129          * We feed with the event bits and changed bits for
 130          * enough information to the callback.
 131          */
 132         atomic_notifier_call_chain(&opal_notifier_head,
 133                                    events, (void *)changed_mask);
 134 }
 135
 136 void opal_notifier_update_evt(uint64_t evt_mask,
 137                               uint64_t evt_val)
 138 {
 139         unsigned long flags;
 140
 141         spin_lock_irqsave(&opal_notifier_lock, flags);
 142         last_notified_mask &= ~evt_mask;
 143         last_notified_mask |= evt_val;
 144         spin_unlock_irqrestore(&opal_notifier_lock, flags);
 145 }
 146
 147 void opal_notifier_enable(void)
 148 {
 149         int64_t rc;
 150         uint64_t evt = 0;
 151
 152         atomic_set(&opal_notifier_hold, 0);
 153
 154         /* Process pending events */
 155         rc = opal_poll_events(&evt);
 156         if (rc == OPAL_SUCCESS && evt)
 157                 opal_do_notifier(evt);
 158 }
 159
 160 void opal_notifier_disable(void)
 161 {
 162         atomic_set(&opal_notifier_hold, 1);
 163 }
 164
 165 int opal_get_chars(uint32_t vtermno, char *buf, int count)
 166 {
 167         s64 len, rc;
 168         u64 evt;
 169
 170         if (!opal.entry)
 171                 return -ENODEV;
 172         opal_poll_events(&evt);
 173         if ((evt & OPAL_EVENT_CONSOLE_INPUT) == 0)
 174                 return 0;
 175         len = count;
 176         rc = opal_console_read(vtermno, &len, buf);
 177         if (rc == OPAL_SUCCESS)
 178                 return len;
 179         return 0;
 180 }
 181
 182 int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
 183 {
 184         int written = 0;
 185         s64 len, rc;
 186         unsigned long flags;
 187         u64 evt;
 188
 189         if (!opal.entry)
 190                 return -ENODEV;
 191
 192         /* We want put_chars to be atomic to avoid mangling of hvsi
 193          * packets. To do that, we first test for room and return
 194          * -EAGAIN if there isn't enough.
 195          *
 196          * Unfortunately, opal_console_write_buffer_space() doesn't
 197          * appear to work on opal v1, so we just assume there is
 198          * enough room and be done with it
 199          */
 200         spin_lock_irqsave(&opal_write_lock, flags);
 201         if (firmware_has_feature(FW_FEATURE_OPALv2)) {
 202                 rc = opal_console_write_buffer_space(vtermno, &len);
 203                 if (rc || len < total_len) {
 204                         spin_unlock_irqrestore(&opal_write_lock, flags);
 205                         /* Closed -> drop characters */
 206                         if (rc)
 207                                 return total_len;
 208                         opal_poll_events(&evt);
 209                         return -EAGAIN;
 210                 }
 211         }
 212
 213         /* We still try to handle partial completions, though they
 214          * should no longer happen.
 215          */
 216         rc = OPAL_BUSY;
 217         while(total_len > 0 && (rc == OPAL_BUSY ||
 218                                 rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
 219                 len = total_len;
 220                 rc = opal_console_write(vtermno, &len, data);
 221
 222                 /* Closed or other error drop */
 223                 if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
 224                     rc != OPAL_BUSY_EVENT) {
 225                         written = total_len;
 226                         break;
 227                 }
 228                 if (rc == OPAL_SUCCESS) {
 229                         total_len -= len;
 230                         data += len;
 231                         written += len;
 232                 }
 233                 /* This is a bit nasty but we need that for the console to
 234                  * flush when there aren't any interrupts. We will clean
 235                  * things a bit later to limit that to synchronous path
 236                  * such as the kernel console and xmon/udbg
 237                  */
 238                 do
 239                         opal_poll_events(&evt);
 240                 while(rc == OPAL_SUCCESS && (evt & OPAL_EVENT_CONSOLE_OUTPUT));
 241         }
 242         spin_unlock_irqrestore(&opal_write_lock, flags);
 243         return written;
 244 }
 245
 246 int opal_machine_check(struct pt_regs *regs)
 247 {
 248         struct opal_machine_check_event *opal_evt = get_paca()->opal_mc_evt;
 249         struct opal_machine_check_event evt;
 250         const char *level, *sevstr, *subtype;
 251         static const char *opal_mc_ue_types[] = {
 252                 "Indeterminate",
 253                 "Instruction fetch",
 254                 "Page table walk ifetch",
 255                 "Load/Store",
 256                 "Page table walk Load/Store",
 257         };
 258         static const char *opal_mc_slb_types[] = {
 259                 "Indeterminate",
 260                 "Parity",
 261                 "Multihit",
 262         };
 263         static const char *opal_mc_erat_types[] = {
 264                 "Indeterminate",
 265                 "Parity",
 266                 "Multihit",
 267         };
 268         static const char *opal_mc_tlb_types[] = {
 269                 "Indeterminate",
 270                 "Parity",
 271                 "Multihit",
 272         };
 273
 274         /* Copy the event structure and release the original */
 275         evt = *opal_evt;
 276         opal_evt->in_use = 0;
 277
 278         /* Print things out */
 279         if (evt.version != OpalMCE_V1) {
 280                 pr_err("Machine Check Exception, Unknown event version %d !\n",
 281                        evt.version);
 282                 return 0;
 283         }
 284         switch(evt.severity) {
 285         case OpalMCE_SEV_NO_ERROR:
 286                 level = KERN_INFO;
 287                 sevstr = "Harmless";
 288                 break;
 289         case OpalMCE_SEV_WARNING:
 290                 level = KERN_WARNING;
 291                 sevstr = "";
 292                 break;
 293         case OpalMCE_SEV_ERROR_SYNC:
 294                 level = KERN_ERR;
 295                 sevstr = "Severe";
 296                 break;
 297         case OpalMCE_SEV_FATAL:
 298         default:
 299                 level = KERN_ERR;
 300                 sevstr = "Fatal";
 301                 break;
 302         }
 303
 304         printk("%s%s Machine check interrupt [%s]\n", level, sevstr,
 305                evt.disposition == OpalMCE_DISPOSITION_RECOVERED ?
 306                "Recovered" : "[Not recovered");
 307         printk("%s  Initiator: %s\n", level,
 308                evt.initiator == OpalMCE_INITIATOR_CPU ? "CPU" : "Unknown");
 309         switch(evt.error_type) {
 310         case OpalMCE_ERROR_TYPE_UE:
 311                 subtype = evt.u.ue_error.ue_error_type <
 312                         ARRAY_SIZE(opal_mc_ue_types) ?
 313                         opal_mc_ue_types[evt.u.ue_error.ue_error_type]
 314                         : "Unknown";
 315                 printk("%s  Error type: UE [%s]\n", level, subtype);
 316                 if (evt.u.ue_error.effective_address_provided)
 317                         printk("%s    Effective address: %016llx\n",
 318                                level, evt.u.ue_error.effective_address);
 319                 if (evt.u.ue_error.physical_address_provided)
 320                         printk("%s      Physial address: %016llx\n",
 321                                level, evt.u.ue_error.physical_address);
 322                 break;
 323         case OpalMCE_ERROR_TYPE_SLB:
 324                 subtype = evt.u.slb_error.slb_error_type <
 325                         ARRAY_SIZE(opal_mc_slb_types) ?
 326                         opal_mc_slb_types[evt.u.slb_error.slb_error_type]
 327                         : "Unknown";
 328                 printk("%s  Error type: SLB [%s]\n", level, subtype);
 329                 if (evt.u.slb_error.effective_address_provided)
 330                         printk("%s    Effective address: %016llx\n",
 331                                level, evt.u.slb_error.effective_address);
 332                 break;
 333         case OpalMCE_ERROR_TYPE_ERAT:
 334                 subtype = evt.u.erat_error.erat_error_type <
 335                         ARRAY_SIZE(opal_mc_erat_types) ?
 336                         opal_mc_erat_types[evt.u.erat_error.erat_error_type]
 337                         : "Unknown";
 338                 printk("%s  Error type: ERAT [%s]\n", level, subtype);
 339                 if (evt.u.erat_error.effective_address_provided)
 340                         printk("%s    Effective address: %016llx\n",
 341                                level, evt.u.erat_error.effective_address);
 342                 break;
 343         case OpalMCE_ERROR_TYPE_TLB:
 344                 subtype = evt.u.tlb_error.tlb_error_type <
 345                         ARRAY_SIZE(opal_mc_tlb_types) ?
 346                         opal_mc_tlb_types[evt.u.tlb_error.tlb_error_type]
 347                         : "Unknown";
 348                 printk("%s  Error type: TLB [%s]\n", level, subtype);
 349                 if (evt.u.tlb_error.effective_address_provided)
 350                         printk("%s    Effective address: %016llx\n",
 351                                level, evt.u.tlb_error.effective_address);
 352                 break;
 353         default:
 354         case OpalMCE_ERROR_TYPE_UNKNOWN:
 355                 printk("%s  Error type: Unknown\n", level);
 356                 break;
 357         }
 358         return evt.severity == OpalMCE_SEV_FATAL ? 0 : 1;
 359 }
 360
 361 static irqreturn_t opal_interrupt(int irq, void *data)
 362 {
 363         uint64_t events;
 364
 365         opal_handle_interrupt(virq_to_hw(irq), &events);
 366
 367         opal_do_notifier(events);
 368
 369         return IRQ_HANDLED;
 370 }
 371
 372 static int __init opal_init(void)
 373 {
 374         struct device_node *np, *consoles;
 375         const u32 *irqs;
 376         int rc, i, irqlen;
 377
 378         opal_node = of_find_node_by_path("/ibm,opal");
 379         if (!opal_node) {
 380                 pr_warn("opal: Node not found\n");
 381                 return -ENODEV;
 382         }
 383
 384         /* Register OPAL consoles if any ports */
 385         if (firmware_has_feature(FW_FEATURE_OPALv2))
 386                 consoles = of_find_node_by_path("/ibm,opal/consoles");
 387         else
 388                 consoles = of_node_get(opal_node);
 389         if (consoles) {
 390                 for_each_child_of_node(consoles, np) {
 391                         if (strcmp(np->name, "serial"))
 392                                 continue;
 393                         of_platform_device_create(np, NULL, NULL);
 394                 }
 395                 of_node_put(consoles);
 396         }
 397
 398         /* Find all OPAL interrupts and request them */
 399         irqs = of_get_property(opal_node, "opal-interrupts", &irqlen);
 400         pr_debug("opal: Found %d interrupts reserved for OPAL\n",
 401                  irqs ? (irqlen / 4) : 0);
 402         opal_irq_count = irqlen / 4;
 403         opal_irqs = kzalloc(opal_irq_count * sizeof(unsigned int), GFP_KERNEL);
 404         for (i = 0; irqs && i < (irqlen / 4); i++, irqs++) {
 405                 unsigned int hwirq = be32_to_cpup(irqs);
 406                 unsigned int irq = irq_create_mapping(NULL, hwirq);
 407                 if (irq == NO_IRQ) {
 408                         pr_warning("opal: Failed to map irq 0x%x\n", hwirq);
 409                         continue;
 410                 }
 411                 rc = request_irq(irq, opal_interrupt, 0, "opal", NULL);
 412                 if (rc)
 413                         pr_warning("opal: Error %d requesting irq %d"
 414                                    " (0x%x)\n", rc, irq, hwirq);
 415                 opal_irqs[i] = irq;
 416         }
 417         return 0;
 418 }
 419 subsys_initcall(opal_init);
 420
 421 void opal_shutdown(void)
 422 {
 423         unsigned int i;
 424
 425         for (i = 0; i < opal_irq_count; i++) {
 426                 if (opal_irqs[i])
 427                         free_irq(opal_irqs[i], NULL);
 428                 opal_irqs[i] = 0;
 429         }
 430 }