12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
27f43e71eSJoel Stanley /*
37f43e71eSJoel Stanley * PowerNV OPAL power control for graceful shutdown handling
47f43e71eSJoel Stanley *
57f43e71eSJoel Stanley * Copyright 2015 IBM Corp.
67f43e71eSJoel Stanley */
77f43e71eSJoel Stanley
83b476aadSVipin K Parashar #define pr_fmt(fmt) "opal-power: " fmt
93b476aadSVipin K Parashar
107f43e71eSJoel Stanley #include <linux/kernel.h>
117f43e71eSJoel Stanley #include <linux/reboot.h>
127f43e71eSJoel Stanley #include <linux/notifier.h>
133b476aadSVipin K Parashar #include <linux/of.h>
147f43e71eSJoel Stanley
157f43e71eSJoel Stanley #include <asm/opal.h>
167f43e71eSJoel Stanley #include <asm/machdep.h>
177f43e71eSJoel Stanley
187f43e71eSJoel Stanley #define SOFT_OFF 0x00
197f43e71eSJoel Stanley #define SOFT_REBOOT 0x01
207f43e71eSJoel Stanley
213b476aadSVipin K Parashar /* Detect EPOW event */
detect_epow(void)223b476aadSVipin K Parashar static bool detect_epow(void)
233b476aadSVipin K Parashar {
243b476aadSVipin K Parashar u16 epow;
253b476aadSVipin K Parashar int i, rc;
263b476aadSVipin K Parashar __be16 epow_classes;
273b476aadSVipin K Parashar __be16 opal_epow_status[OPAL_SYSEPOW_MAX] = {0};
283b476aadSVipin K Parashar
293b476aadSVipin K Parashar /*
303b476aadSVipin K Parashar * Check for EPOW event. Kernel sends supported EPOW classes info
313b476aadSVipin K Parashar * to OPAL. OPAL returns EPOW info along with classes present.
323b476aadSVipin K Parashar */
333b476aadSVipin K Parashar epow_classes = cpu_to_be16(OPAL_SYSEPOW_MAX);
343b476aadSVipin K Parashar rc = opal_get_epow_status(opal_epow_status, &epow_classes);
353b476aadSVipin K Parashar if (rc != OPAL_SUCCESS) {
363b476aadSVipin K Parashar pr_err("Failed to get EPOW event information\n");
373b476aadSVipin K Parashar return false;
383b476aadSVipin K Parashar }
393b476aadSVipin K Parashar
403b476aadSVipin K Parashar /* Look for EPOW events present */
413b476aadSVipin K Parashar for (i = 0; i < be16_to_cpu(epow_classes); i++) {
423b476aadSVipin K Parashar epow = be16_to_cpu(opal_epow_status[i]);
433b476aadSVipin K Parashar
443b476aadSVipin K Parashar /* Filter events which do not need shutdown. */
453b476aadSVipin K Parashar if (i == OPAL_SYSEPOW_POWER)
463b476aadSVipin K Parashar epow &= ~(OPAL_SYSPOWER_CHNG | OPAL_SYSPOWER_FAIL |
473b476aadSVipin K Parashar OPAL_SYSPOWER_INCL);
483b476aadSVipin K Parashar if (epow)
493b476aadSVipin K Parashar return true;
503b476aadSVipin K Parashar }
513b476aadSVipin K Parashar
523b476aadSVipin K Parashar return false;
533b476aadSVipin K Parashar }
543b476aadSVipin K Parashar
553b476aadSVipin K Parashar /* Check for existing EPOW, DPO events */
poweroff_pending(void)56*e5913db1SNick Child static bool __init poweroff_pending(void)
573b476aadSVipin K Parashar {
583b476aadSVipin K Parashar int rc;
593b476aadSVipin K Parashar __be64 opal_dpo_timeout;
603b476aadSVipin K Parashar
613b476aadSVipin K Parashar /* Check for DPO event */
623b476aadSVipin K Parashar rc = opal_get_dpo_status(&opal_dpo_timeout);
633b476aadSVipin K Parashar if (rc == OPAL_SUCCESS) {
643b476aadSVipin K Parashar pr_info("Existing DPO event detected.\n");
653b476aadSVipin K Parashar return true;
663b476aadSVipin K Parashar }
673b476aadSVipin K Parashar
683b476aadSVipin K Parashar /* Check for EPOW event */
693b476aadSVipin K Parashar if (detect_epow()) {
703b476aadSVipin K Parashar pr_info("Existing EPOW event detected.\n");
713b476aadSVipin K Parashar return true;
723b476aadSVipin K Parashar }
733b476aadSVipin K Parashar
743b476aadSVipin K Parashar return false;
753b476aadSVipin K Parashar }
763b476aadSVipin K Parashar
773b476aadSVipin K Parashar /* OPAL power-control events notifier */
opal_power_control_event(struct notifier_block * nb,unsigned long msg_type,void * msg)787f43e71eSJoel Stanley static int opal_power_control_event(struct notifier_block *nb,
797f43e71eSJoel Stanley unsigned long msg_type, void *msg)
807f43e71eSJoel Stanley {
817f43e71eSJoel Stanley uint64_t type;
827f43e71eSJoel Stanley
833b476aadSVipin K Parashar switch (msg_type) {
843b476aadSVipin K Parashar case OPAL_MSG_EPOW:
853b476aadSVipin K Parashar if (detect_epow()) {
863b476aadSVipin K Parashar pr_info("EPOW msg received. Powering off system\n");
873b476aadSVipin K Parashar orderly_poweroff(true);
883b476aadSVipin K Parashar }
893b476aadSVipin K Parashar break;
903b476aadSVipin K Parashar case OPAL_MSG_DPO:
913b476aadSVipin K Parashar pr_info("DPO msg received. Powering off system\n");
923b476aadSVipin K Parashar orderly_poweroff(true);
933b476aadSVipin K Parashar break;
943b476aadSVipin K Parashar case OPAL_MSG_SHUTDOWN:
953b476aadSVipin K Parashar type = be64_to_cpu(((struct opal_msg *)msg)->params[0]);
967f43e71eSJoel Stanley switch (type) {
977f43e71eSJoel Stanley case SOFT_REBOOT:
983b476aadSVipin K Parashar pr_info("Reboot requested\n");
99e243304dSJoel Stanley orderly_reboot();
100e243304dSJoel Stanley break;
1017f43e71eSJoel Stanley case SOFT_OFF:
1023b476aadSVipin K Parashar pr_info("Poweroff requested\n");
1037f43e71eSJoel Stanley orderly_poweroff(true);
1047f43e71eSJoel Stanley break;
1057f43e71eSJoel Stanley default:
1063b476aadSVipin K Parashar pr_err("Unknown power-control type %llu\n", type);
1073b476aadSVipin K Parashar }
1083b476aadSVipin K Parashar break;
1093b476aadSVipin K Parashar default:
1103b476aadSVipin K Parashar pr_err("Unknown OPAL message type %lu\n", msg_type);
1117f43e71eSJoel Stanley }
1127f43e71eSJoel Stanley
1137f43e71eSJoel Stanley return 0;
1147f43e71eSJoel Stanley }
1157f43e71eSJoel Stanley
1163b476aadSVipin K Parashar /* OPAL EPOW event notifier block */
1173b476aadSVipin K Parashar static struct notifier_block opal_epow_nb = {
1183b476aadSVipin K Parashar .notifier_call = opal_power_control_event,
1193b476aadSVipin K Parashar .next = NULL,
1203b476aadSVipin K Parashar .priority = 0,
1213b476aadSVipin K Parashar };
1223b476aadSVipin K Parashar
1233b476aadSVipin K Parashar /* OPAL DPO event notifier block */
1243b476aadSVipin K Parashar static struct notifier_block opal_dpo_nb = {
1253b476aadSVipin K Parashar .notifier_call = opal_power_control_event,
1263b476aadSVipin K Parashar .next = NULL,
1273b476aadSVipin K Parashar .priority = 0,
1283b476aadSVipin K Parashar };
1293b476aadSVipin K Parashar
1303b476aadSVipin K Parashar /* OPAL power-control event notifier block */
1317f43e71eSJoel Stanley static struct notifier_block opal_power_control_nb = {
1327f43e71eSJoel Stanley .notifier_call = opal_power_control_event,
1337f43e71eSJoel Stanley .next = NULL,
1347f43e71eSJoel Stanley .priority = 0,
1357f43e71eSJoel Stanley };
1367f43e71eSJoel Stanley
opal_power_control_init(void)13708fb726dSMahesh Salgaonkar int __init opal_power_control_init(void)
1387f43e71eSJoel Stanley {
1393b476aadSVipin K Parashar int ret, supported = 0;
1403b476aadSVipin K Parashar struct device_node *np;
1417f43e71eSJoel Stanley
1423b476aadSVipin K Parashar /* Register OPAL power-control events notifier */
1437f43e71eSJoel Stanley ret = opal_message_notifier_register(OPAL_MSG_SHUTDOWN,
1447f43e71eSJoel Stanley &opal_power_control_nb);
1453b476aadSVipin K Parashar if (ret)
1463b476aadSVipin K Parashar pr_err("Failed to register SHUTDOWN notifier, ret = %d\n", ret);
1473b476aadSVipin K Parashar
1483b476aadSVipin K Parashar /* Determine OPAL EPOW, DPO support */
1493b476aadSVipin K Parashar np = of_find_node_by_path("/ibm,opal/epow");
1503b476aadSVipin K Parashar if (np) {
1513b476aadSVipin K Parashar supported = of_device_is_compatible(np, "ibm,opal-v3-epow");
1523b476aadSVipin K Parashar of_node_put(np);
1537f43e71eSJoel Stanley }
1547f43e71eSJoel Stanley
1553b476aadSVipin K Parashar if (!supported)
1563b476aadSVipin K Parashar return 0;
1573b476aadSVipin K Parashar pr_info("OPAL EPOW, DPO support detected.\n");
1583b476aadSVipin K Parashar
1593b476aadSVipin K Parashar /* Register EPOW event notifier */
1603b476aadSVipin K Parashar ret = opal_message_notifier_register(OPAL_MSG_EPOW, &opal_epow_nb);
1613b476aadSVipin K Parashar if (ret)
1623b476aadSVipin K Parashar pr_err("Failed to register EPOW notifier, ret = %d\n", ret);
1633b476aadSVipin K Parashar
1643b476aadSVipin K Parashar /* Register DPO event notifier */
1653b476aadSVipin K Parashar ret = opal_message_notifier_register(OPAL_MSG_DPO, &opal_dpo_nb);
1663b476aadSVipin K Parashar if (ret)
1673b476aadSVipin K Parashar pr_err("Failed to register DPO notifier, ret = %d\n", ret);
1683b476aadSVipin K Parashar
1693b476aadSVipin K Parashar /* Check for any pending EPOW or DPO events. */
1703b476aadSVipin K Parashar if (poweroff_pending())
1713b476aadSVipin K Parashar orderly_poweroff(true);
1723b476aadSVipin K Parashar
1737f43e71eSJoel Stanley return 0;
1747f43e71eSJoel Stanley }
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