linux/arch/powerpc/platforms/powernv/opal.c
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   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 <asm/opal.h>
  19#include <asm/firmware.h>
  20
  21#include "powernv.h"
  22
  23struct opal {
  24        u64 base;
  25        u64 entry;
  26} opal;
  27
  28static struct device_node *opal_node;
  29static DEFINE_SPINLOCK(opal_write_lock);
  30extern u64 opal_mc_secondary_handler[];
  31
  32int __init early_init_dt_scan_opal(unsigned long node,
  33                                   const char *uname, int depth, void *data)
  34{
  35        const void *basep, *entryp;
  36        unsigned long basesz, entrysz;
  37        u64 glue;
  38
  39        if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
  40                return 0;
  41
  42        basep  = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
  43        entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
  44
  45        if (!basep || !entryp)
  46                return 1;
  47
  48        opal.base = of_read_number(basep, basesz/4);
  49        opal.entry = of_read_number(entryp, entrysz/4);
  50
  51        pr_debug("OPAL Base  = 0x%llx (basep=%p basesz=%ld)\n",
  52                 opal.base, basep, basesz);
  53        pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%ld)\n",
  54                 opal.entry, entryp, entrysz);
  55
  56        powerpc_firmware_features |= FW_FEATURE_OPAL;
  57        if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) {
  58                powerpc_firmware_features |= FW_FEATURE_OPALv2;
  59                printk("OPAL V2 detected !\n");
  60        } else {
  61                printk("OPAL V1 detected !\n");
  62        }
  63
  64        /* Hookup some exception handlers. We use the fwnmi area at 0x7000
  65         * to provide the glue space to OPAL
  66         */
  67        glue = 0x7000;
  68        opal_register_exception_handler(OPAL_MACHINE_CHECK_HANDLER,
  69                                        __pa(opal_mc_secondary_handler[0]),
  70                                        glue);
  71        glue += 128;
  72        opal_register_exception_handler(OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
  73                                        0, glue);
  74        glue += 128;
  75        opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
  76
  77        return 1;
  78}
  79
  80int opal_get_chars(uint32_t vtermno, char *buf, int count)
  81{
  82        s64 len, rc;
  83        u64 evt;
  84
  85        if (!opal.entry)
  86                return -ENODEV;
  87        opal_poll_events(&evt);
  88        if ((evt & OPAL_EVENT_CONSOLE_INPUT) == 0)
  89                return 0;
  90        len = count;
  91        rc = opal_console_read(vtermno, &len, buf);
  92        if (rc == OPAL_SUCCESS)
  93                return len;
  94        return 0;
  95}
  96
  97int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
  98{
  99        int written = 0;
 100        s64 len, rc;
 101        unsigned long flags;
 102        u64 evt;
 103
 104        if (!opal.entry)
 105                return -ENODEV;
 106
 107        /* We want put_chars to be atomic to avoid mangling of hvsi
 108         * packets. To do that, we first test for room and return
 109         * -EAGAIN if there isn't enough.
 110         *
 111         * Unfortunately, opal_console_write_buffer_space() doesn't
 112         * appear to work on opal v1, so we just assume there is
 113         * enough room and be done with it
 114         */
 115        spin_lock_irqsave(&opal_write_lock, flags);
 116        if (firmware_has_feature(FW_FEATURE_OPALv2)) {
 117                rc = opal_console_write_buffer_space(vtermno, &len);
 118                if (rc || len < total_len) {
 119                        spin_unlock_irqrestore(&opal_write_lock, flags);
 120                        /* Closed -> drop characters */
 121                        if (rc)
 122                                return total_len;
 123                        opal_poll_events(&evt);
 124                        return -EAGAIN;
 125                }
 126        }
 127
 128        /* We still try to handle partial completions, though they
 129         * should no longer happen.
 130         */
 131        rc = OPAL_BUSY;
 132        while(total_len > 0 && (rc == OPAL_BUSY ||
 133                                rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
 134                len = total_len;
 135                rc = opal_console_write(vtermno, &len, data);
 136                if (rc == OPAL_SUCCESS) {
 137                        total_len -= len;
 138                        data += len;
 139                        written += len;
 140                }
 141                /* This is a bit nasty but we need that for the console to
 142                 * flush when there aren't any interrupts. We will clean
 143                 * things a bit later to limit that to synchronous path
 144                 * such as the kernel console and xmon/udbg
 145                 */
 146                do
 147                        opal_poll_events(&evt);
 148                while(rc == OPAL_SUCCESS && (evt & OPAL_EVENT_CONSOLE_OUTPUT));
 149        }
 150        spin_unlock_irqrestore(&opal_write_lock, flags);
 151        return written;
 152}
 153
 154int opal_machine_check(struct pt_regs *regs)
 155{
 156        struct opal_machine_check_event *opal_evt = get_paca()->opal_mc_evt;
 157        struct opal_machine_check_event evt;
 158        const char *level, *sevstr, *subtype;
 159        static const char *opal_mc_ue_types[] = {
 160                "Indeterminate",
 161                "Instruction fetch",
 162                "Page table walk ifetch",
 163                "Load/Store",
 164                "Page table walk Load/Store",
 165        };
 166        static const char *opal_mc_slb_types[] = {
 167                "Indeterminate",
 168                "Parity",
 169                "Multihit",
 170        };
 171        static const char *opal_mc_erat_types[] = {
 172                "Indeterminate",
 173                "Parity",
 174                "Multihit",
 175        };
 176        static const char *opal_mc_tlb_types[] = {
 177                "Indeterminate",
 178                "Parity",
 179                "Multihit",
 180        };
 181
 182        /* Copy the event structure and release the original */
 183        evt = *opal_evt;
 184        opal_evt->in_use = 0;
 185
 186        /* Print things out */
 187        if (evt.version != OpalMCE_V1) {
 188                pr_err("Machine Check Exception, Unknown event version %d !\n",
 189                       evt.version);
 190                return 0;
 191        }
 192        switch(evt.severity) {
 193        case OpalMCE_SEV_NO_ERROR:
 194                level = KERN_INFO;
 195                sevstr = "Harmless";
 196                break;
 197        case OpalMCE_SEV_WARNING:
 198                level = KERN_WARNING;
 199                sevstr = "";
 200                break;
 201        case OpalMCE_SEV_ERROR_SYNC:
 202                level = KERN_ERR;
 203                sevstr = "Severe";
 204                break;
 205        case OpalMCE_SEV_FATAL:
 206        default:
 207                level = KERN_ERR;
 208                sevstr = "Fatal";
 209                break;
 210        }
 211
 212        printk("%s%s Machine check interrupt [%s]\n", level, sevstr,
 213               evt.disposition == OpalMCE_DISPOSITION_RECOVERED ?
 214               "Recovered" : "[Not recovered");
 215        printk("%s  Initiator: %s\n", level,
 216               evt.initiator == OpalMCE_INITIATOR_CPU ? "CPU" : "Unknown");
 217        switch(evt.error_type) {
 218        case OpalMCE_ERROR_TYPE_UE:
 219                subtype = evt.u.ue_error.ue_error_type <
 220                        ARRAY_SIZE(opal_mc_ue_types) ?
 221                        opal_mc_ue_types[evt.u.ue_error.ue_error_type]
 222                        : "Unknown";
 223                printk("%s  Error type: UE [%s]\n", level, subtype);
 224                if (evt.u.ue_error.effective_address_provided)
 225                        printk("%s    Effective address: %016llx\n",
 226                               level, evt.u.ue_error.effective_address);
 227                if (evt.u.ue_error.physical_address_provided)
 228                        printk("%s      Physial address: %016llx\n",
 229                               level, evt.u.ue_error.physical_address);
 230                break;
 231        case OpalMCE_ERROR_TYPE_SLB:
 232                subtype = evt.u.slb_error.slb_error_type <
 233                        ARRAY_SIZE(opal_mc_slb_types) ?
 234                        opal_mc_slb_types[evt.u.slb_error.slb_error_type]
 235                        : "Unknown";
 236                printk("%s  Error type: SLB [%s]\n", level, subtype);
 237                if (evt.u.slb_error.effective_address_provided)
 238                        printk("%s    Effective address: %016llx\n",
 239                               level, evt.u.slb_error.effective_address);
 240                break;
 241        case OpalMCE_ERROR_TYPE_ERAT:
 242                subtype = evt.u.erat_error.erat_error_type <
 243                        ARRAY_SIZE(opal_mc_erat_types) ?
 244                        opal_mc_erat_types[evt.u.erat_error.erat_error_type]
 245                        : "Unknown";
 246                printk("%s  Error type: ERAT [%s]\n", level, subtype);
 247                if (evt.u.erat_error.effective_address_provided)
 248                        printk("%s    Effective address: %016llx\n",
 249                               level, evt.u.erat_error.effective_address);
 250                break;
 251        case OpalMCE_ERROR_TYPE_TLB:
 252                subtype = evt.u.tlb_error.tlb_error_type <
 253                        ARRAY_SIZE(opal_mc_tlb_types) ?
 254                        opal_mc_tlb_types[evt.u.tlb_error.tlb_error_type]
 255                        : "Unknown";
 256                printk("%s  Error type: TLB [%s]\n", level, subtype);
 257                if (evt.u.tlb_error.effective_address_provided)
 258                        printk("%s    Effective address: %016llx\n",
 259                               level, evt.u.tlb_error.effective_address);
 260                break;
 261        default:
 262        case OpalMCE_ERROR_TYPE_UNKNOWN:
 263                printk("%s  Error type: Unknown\n", level);
 264                break;
 265        }
 266        return evt.severity == OpalMCE_SEV_FATAL ? 0 : 1;
 267}
 268
 269static irqreturn_t opal_interrupt(int irq, void *data)
 270{
 271        uint64_t events;
 272
 273        opal_handle_interrupt(virq_to_hw(irq), &events);
 274
 275        /* XXX TODO: Do something with the events */
 276
 277        return IRQ_HANDLED;
 278}
 279
 280static int __init opal_init(void)
 281{
 282        struct device_node *np, *consoles;
 283        const u32 *irqs;
 284        int rc, i, irqlen;
 285
 286        opal_node = of_find_node_by_path("/ibm,opal");
 287        if (!opal_node) {
 288                pr_warn("opal: Node not found\n");
 289                return -ENODEV;
 290        }
 291        if (firmware_has_feature(FW_FEATURE_OPALv2))
 292                consoles = of_find_node_by_path("/ibm,opal/consoles");
 293        else
 294                consoles = of_node_get(opal_node);
 295
 296        /* Register serial ports */
 297        for_each_child_of_node(consoles, np) {
 298                if (strcmp(np->name, "serial"))
 299                        continue;
 300                of_platform_device_create(np, NULL, NULL);
 301        }
 302        of_node_put(consoles);
 303
 304        /* Find all OPAL interrupts and request them */
 305        irqs = of_get_property(opal_node, "opal-interrupts", &irqlen);
 306        pr_debug("opal: Found %d interrupts reserved for OPAL\n",
 307                 irqs ? (irqlen / 4) : 0);
 308        for (i = 0; irqs && i < (irqlen / 4); i++, irqs++) {
 309                unsigned int hwirq = be32_to_cpup(irqs);
 310                unsigned int irq = irq_create_mapping(NULL, hwirq);
 311                if (irq == NO_IRQ) {
 312                        pr_warning("opal: Failed to map irq 0x%x\n", hwirq);
 313                        continue;
 314                }
 315                rc = request_irq(irq, opal_interrupt, 0, "opal", NULL);
 316                if (rc)
 317                        pr_warning("opal: Error %d requesting irq %d"
 318                                   " (0x%x)\n", rc, irq, hwirq);
 319        }
 320        return 0;
 321}
 322subsys_initcall(opal_init);
 323