1 /* 2 * OPAL hypervisor Maintenance interrupt handling support in PowreNV. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; If not, see <http://www.gnu.org/licenses/>. 16 * 17 * Copyright 2014 IBM Corporation 18 * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> 19 */ 20 21 #undef DEBUG 22 23 #include <linux/kernel.h> 24 #include <linux/init.h> 25 #include <linux/of.h> 26 #include <linux/mm.h> 27 #include <linux/slab.h> 28 29 #include <asm/opal.h> 30 #include <asm/cputable.h> 31 #include <asm/machdep.h> 32 33 static int opal_hmi_handler_nb_init; 34 struct OpalHmiEvtNode { 35 struct list_head list; 36 struct OpalHMIEvent hmi_evt; 37 }; 38 static LIST_HEAD(opal_hmi_evt_list); 39 static DEFINE_SPINLOCK(opal_hmi_evt_lock); 40 41 static void print_hmi_event_info(struct OpalHMIEvent *hmi_evt) 42 { 43 const char *level, *sevstr, *error_info; 44 static const char *hmi_error_types[] = { 45 "Malfunction Alert", 46 "Processor Recovery done", 47 "Processor recovery occurred again", 48 "Processor recovery occurred for masked error", 49 "Timer facility experienced an error", 50 "TFMR SPR is corrupted", 51 "UPS (Uniterrupted Power System) Overflow indication", 52 "An XSCOM operation failure", 53 "An XSCOM operation completed", 54 "SCOM has set a reserved FIR bit to cause recovery", 55 "Debug trigger has set a reserved FIR bit to cause recovery", 56 "A hypervisor resource error occurred" 57 }; 58 59 /* Print things out */ 60 if (hmi_evt->version < OpalHMIEvt_V1) { 61 pr_err("HMI Interrupt, Unknown event version %d !\n", 62 hmi_evt->version); 63 return; 64 } 65 switch (hmi_evt->severity) { 66 case OpalHMI_SEV_NO_ERROR: 67 level = KERN_INFO; 68 sevstr = "Harmless"; 69 break; 70 case OpalHMI_SEV_WARNING: 71 level = KERN_WARNING; 72 sevstr = ""; 73 break; 74 case OpalHMI_SEV_ERROR_SYNC: 75 level = KERN_ERR; 76 sevstr = "Severe"; 77 break; 78 case OpalHMI_SEV_FATAL: 79 default: 80 level = KERN_ERR; 81 sevstr = "Fatal"; 82 break; 83 } 84 85 printk("%s%s Hypervisor Maintenance interrupt [%s]\n", 86 level, sevstr, 87 hmi_evt->disposition == OpalHMI_DISPOSITION_RECOVERED ? 88 "Recovered" : "Not recovered"); 89 error_info = hmi_evt->type < ARRAY_SIZE(hmi_error_types) ? 90 hmi_error_types[hmi_evt->type] 91 : "Unknown"; 92 printk("%s Error detail: %s\n", level, error_info); 93 printk("%s HMER: %016llx\n", level, be64_to_cpu(hmi_evt->hmer)); 94 if ((hmi_evt->type == OpalHMI_ERROR_TFAC) || 95 (hmi_evt->type == OpalHMI_ERROR_TFMR_PARITY)) 96 printk("%s TFMR: %016llx\n", level, 97 be64_to_cpu(hmi_evt->tfmr)); 98 } 99 100 static void hmi_event_handler(struct work_struct *work) 101 { 102 unsigned long flags; 103 struct OpalHMIEvent *hmi_evt; 104 struct OpalHmiEvtNode *msg_node; 105 uint8_t disposition; 106 107 spin_lock_irqsave(&opal_hmi_evt_lock, flags); 108 while (!list_empty(&opal_hmi_evt_list)) { 109 msg_node = list_entry(opal_hmi_evt_list.next, 110 struct OpalHmiEvtNode, list); 111 list_del(&msg_node->list); 112 spin_unlock_irqrestore(&opal_hmi_evt_lock, flags); 113 114 hmi_evt = (struct OpalHMIEvent *) &msg_node->hmi_evt; 115 print_hmi_event_info(hmi_evt); 116 disposition = hmi_evt->disposition; 117 kfree(msg_node); 118 119 /* 120 * Check if HMI event has been recovered or not. If not 121 * then we can't continue, invoke panic. 122 */ 123 if (disposition != OpalHMI_DISPOSITION_RECOVERED) 124 panic("Unrecoverable HMI exception"); 125 126 spin_lock_irqsave(&opal_hmi_evt_lock, flags); 127 } 128 spin_unlock_irqrestore(&opal_hmi_evt_lock, flags); 129 } 130 131 static DECLARE_WORK(hmi_event_work, hmi_event_handler); 132 /* 133 * opal_handle_hmi_event - notifier handler that queues up HMI events 134 * to be preocessed later. 135 */ 136 static int opal_handle_hmi_event(struct notifier_block *nb, 137 unsigned long msg_type, void *msg) 138 { 139 unsigned long flags; 140 struct OpalHMIEvent *hmi_evt; 141 struct opal_msg *hmi_msg = msg; 142 struct OpalHmiEvtNode *msg_node; 143 144 /* Sanity Checks */ 145 if (msg_type != OPAL_MSG_HMI_EVT) 146 return 0; 147 148 /* HMI event info starts from param[0] */ 149 hmi_evt = (struct OpalHMIEvent *)&hmi_msg->params[0]; 150 151 /* Delay the logging of HMI events to workqueue. */ 152 msg_node = kzalloc(sizeof(*msg_node), GFP_ATOMIC); 153 if (!msg_node) { 154 pr_err("HMI: out of memory, Opal message event not handled\n"); 155 return -ENOMEM; 156 } 157 memcpy(&msg_node->hmi_evt, hmi_evt, sizeof(struct OpalHMIEvent)); 158 159 spin_lock_irqsave(&opal_hmi_evt_lock, flags); 160 list_add(&msg_node->list, &opal_hmi_evt_list); 161 spin_unlock_irqrestore(&opal_hmi_evt_lock, flags); 162 163 schedule_work(&hmi_event_work); 164 return 0; 165 } 166 167 static struct notifier_block opal_hmi_handler_nb = { 168 .notifier_call = opal_handle_hmi_event, 169 .next = NULL, 170 .priority = 0, 171 }; 172 173 static int __init opal_hmi_handler_init(void) 174 { 175 int ret; 176 177 if (!opal_hmi_handler_nb_init) { 178 ret = opal_message_notifier_register( 179 OPAL_MSG_HMI_EVT, &opal_hmi_handler_nb); 180 if (ret) { 181 pr_err("%s: Can't register OPAL event notifier (%d)\n", 182 __func__, ret); 183 return ret; 184 } 185 opal_hmi_handler_nb_init = 1; 186 } 187 return 0; 188 } 189 machine_subsys_initcall(powernv, opal_hmi_handler_init); 190