diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/opal-power.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/opal-power.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/opal-power.c b/arch/powerpc/platforms/powernv/opal-power.c new file mode 100644 index 000000000..58dc33082 --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal-power.c @@ -0,0 +1,179 @@ +/* + * PowerNV OPAL power control for graceful shutdown handling + * + * Copyright 2015 IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#define pr_fmt(fmt) "opal-power: " fmt + +#include <linux/kernel.h> +#include <linux/reboot.h> +#include <linux/notifier.h> +#include <linux/of.h> + +#include <asm/opal.h> +#include <asm/machdep.h> + +#define SOFT_OFF 0x00 +#define SOFT_REBOOT 0x01 + +/* Detect EPOW event */ +static bool detect_epow(void) +{ + u16 epow; + int i, rc; + __be16 epow_classes; + __be16 opal_epow_status[OPAL_SYSEPOW_MAX] = {0}; + + /* + * Check for EPOW event. Kernel sends supported EPOW classes info + * to OPAL. OPAL returns EPOW info along with classes present. + */ + epow_classes = cpu_to_be16(OPAL_SYSEPOW_MAX); + rc = opal_get_epow_status(opal_epow_status, &epow_classes); + if (rc != OPAL_SUCCESS) { + pr_err("Failed to get EPOW event information\n"); + return false; + } + + /* Look for EPOW events present */ + for (i = 0; i < be16_to_cpu(epow_classes); i++) { + epow = be16_to_cpu(opal_epow_status[i]); + + /* Filter events which do not need shutdown. */ + if (i == OPAL_SYSEPOW_POWER) + epow &= ~(OPAL_SYSPOWER_CHNG | OPAL_SYSPOWER_FAIL | + OPAL_SYSPOWER_INCL); + if (epow) + return true; + } + + return false; +} + +/* Check for existing EPOW, DPO events */ +static bool poweroff_pending(void) +{ + int rc; + __be64 opal_dpo_timeout; + + /* Check for DPO event */ + rc = opal_get_dpo_status(&opal_dpo_timeout); + if (rc == OPAL_SUCCESS) { + pr_info("Existing DPO event detected.\n"); + return true; + } + + /* Check for EPOW event */ + if (detect_epow()) { + pr_info("Existing EPOW event detected.\n"); + return true; + } + + return false; +} + +/* OPAL power-control events notifier */ +static int opal_power_control_event(struct notifier_block *nb, + unsigned long msg_type, void *msg) +{ + uint64_t type; + + switch (msg_type) { + case OPAL_MSG_EPOW: + if (detect_epow()) { + pr_info("EPOW msg received. Powering off system\n"); + orderly_poweroff(true); + } + break; + case OPAL_MSG_DPO: + pr_info("DPO msg received. Powering off system\n"); + orderly_poweroff(true); + break; + case OPAL_MSG_SHUTDOWN: + type = be64_to_cpu(((struct opal_msg *)msg)->params[0]); + switch (type) { + case SOFT_REBOOT: + pr_info("Reboot requested\n"); + orderly_reboot(); + break; + case SOFT_OFF: + pr_info("Poweroff requested\n"); + orderly_poweroff(true); + break; + default: + pr_err("Unknown power-control type %llu\n", type); + } + break; + default: + pr_err("Unknown OPAL message type %lu\n", msg_type); + } + + return 0; +} + +/* OPAL EPOW event notifier block */ +static struct notifier_block opal_epow_nb = { + .notifier_call = opal_power_control_event, + .next = NULL, + .priority = 0, +}; + +/* OPAL DPO event notifier block */ +static struct notifier_block opal_dpo_nb = { + .notifier_call = opal_power_control_event, + .next = NULL, + .priority = 0, +}; + +/* OPAL power-control event notifier block */ +static struct notifier_block opal_power_control_nb = { + .notifier_call = opal_power_control_event, + .next = NULL, + .priority = 0, +}; + +static int __init opal_power_control_init(void) +{ + int ret, supported = 0; + struct device_node *np; + + /* Register OPAL power-control events notifier */ + ret = opal_message_notifier_register(OPAL_MSG_SHUTDOWN, + &opal_power_control_nb); + if (ret) + pr_err("Failed to register SHUTDOWN notifier, ret = %d\n", ret); + + /* Determine OPAL EPOW, DPO support */ + np = of_find_node_by_path("/ibm,opal/epow"); + if (np) { + supported = of_device_is_compatible(np, "ibm,opal-v3-epow"); + of_node_put(np); + } + + if (!supported) + return 0; + pr_info("OPAL EPOW, DPO support detected.\n"); + + /* Register EPOW event notifier */ + ret = opal_message_notifier_register(OPAL_MSG_EPOW, &opal_epow_nb); + if (ret) + pr_err("Failed to register EPOW notifier, ret = %d\n", ret); + + /* Register DPO event notifier */ + ret = opal_message_notifier_register(OPAL_MSG_DPO, &opal_dpo_nb); + if (ret) + pr_err("Failed to register DPO notifier, ret = %d\n", ret); + + /* Check for any pending EPOW or DPO events. */ + if (poweroff_pending()) + orderly_poweroff(true); + + return 0; +} +machine_subsys_initcall(powernv, opal_power_control_init); |