17f43e71eSJoel Stanley /* 27f43e71eSJoel Stanley * PowerNV OPAL power control for graceful shutdown handling 37f43e71eSJoel Stanley * 47f43e71eSJoel Stanley * Copyright 2015 IBM Corp. 57f43e71eSJoel Stanley * 67f43e71eSJoel Stanley * This program is free software; you can redistribute it and/or 77f43e71eSJoel Stanley * modify it under the terms of the GNU General Public License 87f43e71eSJoel Stanley * as published by the Free Software Foundation; either version 97f43e71eSJoel Stanley * 2 of the License, or (at your option) any later version. 107f43e71eSJoel Stanley */ 117f43e71eSJoel Stanley 123b476aadSVipin K Parashar #define pr_fmt(fmt) "opal-power: " fmt 133b476aadSVipin K Parashar 147f43e71eSJoel Stanley #include <linux/kernel.h> 157f43e71eSJoel Stanley #include <linux/reboot.h> 167f43e71eSJoel Stanley #include <linux/notifier.h> 173b476aadSVipin K Parashar #include <linux/of.h> 187f43e71eSJoel Stanley 197f43e71eSJoel Stanley #include <asm/opal.h> 207f43e71eSJoel Stanley #include <asm/machdep.h> 217f43e71eSJoel Stanley 227f43e71eSJoel Stanley #define SOFT_OFF 0x00 237f43e71eSJoel Stanley #define SOFT_REBOOT 0x01 247f43e71eSJoel Stanley 253b476aadSVipin K Parashar /* Detect EPOW event */ 263b476aadSVipin K Parashar static bool detect_epow(void) 273b476aadSVipin K Parashar { 283b476aadSVipin K Parashar u16 epow; 293b476aadSVipin K Parashar int i, rc; 303b476aadSVipin K Parashar __be16 epow_classes; 313b476aadSVipin K Parashar __be16 opal_epow_status[OPAL_SYSEPOW_MAX] = {0}; 323b476aadSVipin K Parashar 333b476aadSVipin K Parashar /* 343b476aadSVipin K Parashar * Check for EPOW event. Kernel sends supported EPOW classes info 353b476aadSVipin K Parashar * to OPAL. OPAL returns EPOW info along with classes present. 363b476aadSVipin K Parashar */ 373b476aadSVipin K Parashar epow_classes = cpu_to_be16(OPAL_SYSEPOW_MAX); 383b476aadSVipin K Parashar rc = opal_get_epow_status(opal_epow_status, &epow_classes); 393b476aadSVipin K Parashar if (rc != OPAL_SUCCESS) { 403b476aadSVipin K Parashar pr_err("Failed to get EPOW event information\n"); 413b476aadSVipin K Parashar return false; 423b476aadSVipin K Parashar } 433b476aadSVipin K Parashar 443b476aadSVipin K Parashar /* Look for EPOW events present */ 453b476aadSVipin K Parashar for (i = 0; i < be16_to_cpu(epow_classes); i++) { 463b476aadSVipin K Parashar epow = be16_to_cpu(opal_epow_status[i]); 473b476aadSVipin K Parashar 483b476aadSVipin K Parashar /* Filter events which do not need shutdown. */ 493b476aadSVipin K Parashar if (i == OPAL_SYSEPOW_POWER) 503b476aadSVipin K Parashar epow &= ~(OPAL_SYSPOWER_CHNG | OPAL_SYSPOWER_FAIL | 513b476aadSVipin K Parashar OPAL_SYSPOWER_INCL); 523b476aadSVipin K Parashar if (epow) 533b476aadSVipin K Parashar return true; 543b476aadSVipin K Parashar } 553b476aadSVipin K Parashar 563b476aadSVipin K Parashar return false; 573b476aadSVipin K Parashar } 583b476aadSVipin K Parashar 593b476aadSVipin K Parashar /* Check for existing EPOW, DPO events */ 603b476aadSVipin K Parashar static bool poweroff_pending(void) 613b476aadSVipin K Parashar { 623b476aadSVipin K Parashar int rc; 633b476aadSVipin K Parashar __be64 opal_dpo_timeout; 643b476aadSVipin K Parashar 653b476aadSVipin K Parashar /* Check for DPO event */ 663b476aadSVipin K Parashar rc = opal_get_dpo_status(&opal_dpo_timeout); 673b476aadSVipin K Parashar if (rc == OPAL_SUCCESS) { 683b476aadSVipin K Parashar pr_info("Existing DPO event detected.\n"); 693b476aadSVipin K Parashar return true; 703b476aadSVipin K Parashar } 713b476aadSVipin K Parashar 723b476aadSVipin K Parashar /* Check for EPOW event */ 733b476aadSVipin K Parashar if (detect_epow()) { 743b476aadSVipin K Parashar pr_info("Existing EPOW event detected.\n"); 753b476aadSVipin K Parashar return true; 763b476aadSVipin K Parashar } 773b476aadSVipin K Parashar 783b476aadSVipin K Parashar return false; 793b476aadSVipin K Parashar } 803b476aadSVipin K Parashar 813b476aadSVipin K Parashar /* OPAL power-control events notifier */ 827f43e71eSJoel Stanley static int opal_power_control_event(struct notifier_block *nb, 837f43e71eSJoel Stanley unsigned long msg_type, void *msg) 847f43e71eSJoel Stanley { 857f43e71eSJoel Stanley uint64_t type; 867f43e71eSJoel Stanley 873b476aadSVipin K Parashar switch (msg_type) { 883b476aadSVipin K Parashar case OPAL_MSG_EPOW: 893b476aadSVipin K Parashar if (detect_epow()) { 903b476aadSVipin K Parashar pr_info("EPOW msg received. Powering off system\n"); 913b476aadSVipin K Parashar orderly_poweroff(true); 923b476aadSVipin K Parashar } 933b476aadSVipin K Parashar break; 943b476aadSVipin K Parashar case OPAL_MSG_DPO: 953b476aadSVipin K Parashar pr_info("DPO msg received. Powering off system\n"); 963b476aadSVipin K Parashar orderly_poweroff(true); 973b476aadSVipin K Parashar break; 983b476aadSVipin K Parashar case OPAL_MSG_SHUTDOWN: 993b476aadSVipin K Parashar type = be64_to_cpu(((struct opal_msg *)msg)->params[0]); 1007f43e71eSJoel Stanley switch (type) { 1017f43e71eSJoel Stanley case SOFT_REBOOT: 1023b476aadSVipin K Parashar pr_info("Reboot requested\n"); 103e243304dSJoel Stanley orderly_reboot(); 104e243304dSJoel Stanley break; 1057f43e71eSJoel Stanley case SOFT_OFF: 1063b476aadSVipin K Parashar pr_info("Poweroff requested\n"); 1077f43e71eSJoel Stanley orderly_poweroff(true); 1087f43e71eSJoel Stanley break; 1097f43e71eSJoel Stanley default: 1103b476aadSVipin K Parashar pr_err("Unknown power-control type %llu\n", type); 1113b476aadSVipin K Parashar } 1123b476aadSVipin K Parashar break; 1133b476aadSVipin K Parashar default: 1143b476aadSVipin K Parashar pr_err("Unknown OPAL message type %lu\n", msg_type); 1157f43e71eSJoel Stanley } 1167f43e71eSJoel Stanley 1177f43e71eSJoel Stanley return 0; 1187f43e71eSJoel Stanley } 1197f43e71eSJoel Stanley 1203b476aadSVipin K Parashar /* OPAL EPOW event notifier block */ 1213b476aadSVipin K Parashar static struct notifier_block opal_epow_nb = { 1223b476aadSVipin K Parashar .notifier_call = opal_power_control_event, 1233b476aadSVipin K Parashar .next = NULL, 1243b476aadSVipin K Parashar .priority = 0, 1253b476aadSVipin K Parashar }; 1263b476aadSVipin K Parashar 1273b476aadSVipin K Parashar /* OPAL DPO event notifier block */ 1283b476aadSVipin K Parashar static struct notifier_block opal_dpo_nb = { 1293b476aadSVipin K Parashar .notifier_call = opal_power_control_event, 1303b476aadSVipin K Parashar .next = NULL, 1313b476aadSVipin K Parashar .priority = 0, 1323b476aadSVipin K Parashar }; 1333b476aadSVipin K Parashar 1343b476aadSVipin K Parashar /* OPAL power-control event notifier block */ 1357f43e71eSJoel Stanley static struct notifier_block opal_power_control_nb = { 1367f43e71eSJoel Stanley .notifier_call = opal_power_control_event, 1377f43e71eSJoel Stanley .next = NULL, 1387f43e71eSJoel Stanley .priority = 0, 1397f43e71eSJoel Stanley }; 1407f43e71eSJoel Stanley 14108fb726dSMahesh Salgaonkar int __init opal_power_control_init(void) 1427f43e71eSJoel Stanley { 1433b476aadSVipin K Parashar int ret, supported = 0; 1443b476aadSVipin K Parashar struct device_node *np; 1457f43e71eSJoel Stanley 1463b476aadSVipin K Parashar /* Register OPAL power-control events notifier */ 1477f43e71eSJoel Stanley ret = opal_message_notifier_register(OPAL_MSG_SHUTDOWN, 1487f43e71eSJoel Stanley &opal_power_control_nb); 1493b476aadSVipin K Parashar if (ret) 1503b476aadSVipin K Parashar pr_err("Failed to register SHUTDOWN notifier, ret = %d\n", ret); 1513b476aadSVipin K Parashar 1523b476aadSVipin K Parashar /* Determine OPAL EPOW, DPO support */ 1533b476aadSVipin K Parashar np = of_find_node_by_path("/ibm,opal/epow"); 1543b476aadSVipin K Parashar if (np) { 1553b476aadSVipin K Parashar supported = of_device_is_compatible(np, "ibm,opal-v3-epow"); 1563b476aadSVipin K Parashar of_node_put(np); 1577f43e71eSJoel Stanley } 1587f43e71eSJoel Stanley 1593b476aadSVipin K Parashar if (!supported) 1603b476aadSVipin K Parashar return 0; 1613b476aadSVipin K Parashar pr_info("OPAL EPOW, DPO support detected.\n"); 1623b476aadSVipin K Parashar 1633b476aadSVipin K Parashar /* Register EPOW event notifier */ 1643b476aadSVipin K Parashar ret = opal_message_notifier_register(OPAL_MSG_EPOW, &opal_epow_nb); 1653b476aadSVipin K Parashar if (ret) 1663b476aadSVipin K Parashar pr_err("Failed to register EPOW notifier, ret = %d\n", ret); 1673b476aadSVipin K Parashar 1683b476aadSVipin K Parashar /* Register DPO event notifier */ 1693b476aadSVipin K Parashar ret = opal_message_notifier_register(OPAL_MSG_DPO, &opal_dpo_nb); 1703b476aadSVipin K Parashar if (ret) 1713b476aadSVipin K Parashar pr_err("Failed to register DPO notifier, ret = %d\n", ret); 1723b476aadSVipin K Parashar 1733b476aadSVipin K Parashar /* Check for any pending EPOW or DPO events. */ 1743b476aadSVipin K Parashar if (poweroff_pending()) 1753b476aadSVipin K Parashar orderly_poweroff(true); 1763b476aadSVipin K Parashar 1777f43e71eSJoel Stanley return 0; 1787f43e71eSJoel Stanley } 179