| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright 2013 Google Inc. |
| * |
| * 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; version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA |
| */ |
| |
| #include <stdint.h> |
| #include <stdlib.h> |
| #include <arch/lib_helpers.h> |
| #include <cpu/cpu.h> |
| #include <console/console.h> |
| #include "cpu-internal.h" |
| |
| struct cpu_info cpu_infos[CONFIG_MAX_CPUS]; |
| struct cpu_info *bsp_cpu_info; |
| |
| struct cpu_info *cpu_info(void) |
| { |
| return cpu_info_for_cpu(smp_processor_id()); |
| } |
| |
| size_t cpus_online(void) |
| { |
| int i; |
| size_t num = 0; |
| |
| for (i = 0; i < ARRAY_SIZE(cpu_infos); i++) { |
| if (cpu_online(cpu_info_for_cpu(i))) |
| num++; |
| } |
| |
| return num; |
| } |
| |
| static inline int action_queue_empty(struct cpu_action_queue *q) |
| { |
| return load_acquire_exclusive(&q->todo) == NULL; |
| } |
| |
| static inline int action_completed(struct cpu_action_queue *q, |
| struct cpu_action *action) |
| { |
| return load_acquire(&q->completed) == action; |
| } |
| |
| static inline void wait_for_action_queue_slot(struct cpu_action_queue *q) |
| { |
| while (!action_queue_empty(q)) |
| wfe(); |
| } |
| |
| static void wait_for_action_complete(struct cpu_action_queue *q, |
| struct cpu_action *a) |
| { |
| while (!action_completed(q, a)) |
| wfe(); |
| } |
| |
| static struct cpu_action *wait_for_action(struct cpu_action_queue *q, |
| struct cpu_action *local) |
| { |
| struct cpu_action *action; |
| |
| while (action_queue_empty(q)) |
| wfe(); |
| |
| /* |
| * Keep original address, but use a local copy for async processing. |
| */ |
| do { |
| action = load_acquire_exclusive(&q->todo); |
| *local = *action; |
| } while (!store_release_exclusive(&q->todo, NULL)); |
| |
| return action; |
| } |
| |
| static void queue_action(struct cpu_action_queue *q, struct cpu_action *action) |
| { |
| do { |
| wait_for_action_queue_slot(q); |
| if (load_acquire_exclusive(&q->todo) != NULL) |
| continue; |
| } while (!store_release_exclusive(&q->todo, action)); |
| } |
| |
| static void action_queue_complete(struct cpu_action_queue *q, |
| struct cpu_action *action) |
| { |
| /* Mark completion and send events to waiters. */ |
| store_release(&q->completed, action); |
| sev(); |
| } |
| |
| static void action_run(struct cpu_action *action) |
| { |
| action->run(action->arg); |
| } |
| |
| static void action_run_on_cpu(struct cpu_info *ci, struct cpu_action *action, |
| int sync) |
| { |
| struct cpu_action_queue *q = &ci->action_queue; |
| |
| /* Don't run actions on non-online cpus. */ |
| if (!cpu_online(ci)) |
| return; |
| |
| if (ci->id == smp_processor_id()) { |
| action->run(action->arg); |
| return; |
| } |
| |
| queue_action(q, action); |
| /* Wait for CPU to pick it up. Empty slot means it was picked up. */ |
| wait_for_action_queue_slot(q); |
| /* Wait for completion if requested. */ |
| if (sync) |
| wait_for_action_complete(q, action); |
| } |
| |
| static int __arch_run_on_cpu(unsigned int cpu, struct cpu_action *action, |
| int sync) |
| { |
| struct cpu_info *ci; |
| |
| if (cpu >= CONFIG_MAX_CPUS) |
| return -1; |
| |
| ci = cpu_info_for_cpu(cpu); |
| |
| action_run_on_cpu(ci, action, sync); |
| |
| return 0; |
| } |
| |
| int arch_run_on_cpu(unsigned int cpu, struct cpu_action *action) |
| { |
| return __arch_run_on_cpu(cpu, action, 1); |
| } |
| |
| int arch_run_on_cpu_async(unsigned int cpu, struct cpu_action *action) |
| { |
| return __arch_run_on_cpu(cpu, action, 0); |
| } |
| |
| static int __arch_run_on_all_cpus(struct cpu_action *action, int sync) |
| { |
| int i; |
| |
| for (i = 0; i < CONFIG_MAX_CPUS; i++) |
| action_run_on_cpu(cpu_info_for_cpu(i), action, sync); |
| |
| return 0; |
| } |
| |
| static int __arch_run_on_all_cpus_but_self(struct cpu_action *action, int sync) |
| { |
| int i; |
| struct cpu_info *me = cpu_info(); |
| |
| for (i = 0; i < CONFIG_MAX_CPUS; i++) { |
| struct cpu_info *ci = cpu_info_for_cpu(i); |
| if (ci == me) |
| continue; |
| action_run_on_cpu(ci, action, sync); |
| } |
| |
| return 0; |
| } |
| |
| int arch_run_on_all_cpus(struct cpu_action *action) |
| { |
| return __arch_run_on_all_cpus(action, 1); |
| } |
| |
| int arch_run_on_all_cpus_async(struct cpu_action *action) |
| { |
| return __arch_run_on_all_cpus(action, 0); |
| } |
| |
| int arch_run_on_all_cpus_but_self(struct cpu_action *action) |
| { |
| return __arch_run_on_all_cpus_but_self(action, 1); |
| } |
| |
| int arch_run_on_all_cpus_but_self_async(struct cpu_action *action) |
| { |
| return __arch_run_on_all_cpus_but_self(action, 0); |
| } |
| |
| |
| void arch_cpu_wait_for_action(void) |
| { |
| struct cpu_info *ci = cpu_info(); |
| struct cpu_action_queue *q = &ci->action_queue; |
| |
| while (1) { |
| struct cpu_action *orig; |
| struct cpu_action action; |
| |
| orig = wait_for_action(q, &action); |
| |
| action_run(&action); |
| action_queue_complete(q, orig); |
| } |
| } |