| /* |
| * 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/barrier.h> |
| #include <arch/lib_helpers.h> |
| #include <cpu/cpu.h> |
| #include <console/console.h> |
| #include "cpu-internal.h" |
| |
| static struct cpu_info cpu_infos[CONFIG_MAX_CPUS]; |
| |
| static inline struct cpu_info *cpu_info_for_cpu(unsigned int id) |
| { |
| return &cpu_infos[id]; |
| } |
| |
| struct cpu_info *cpu_info(void) |
| { |
| return cpu_info_for_cpu(smp_processor_id()); |
| } |
| |
| static int cpu_online(struct cpu_info *ci) |
| { |
| return load_acquire(&ci->online) != 0; |
| } |
| |
| static void cpu_mark_online(struct cpu_info *ci) |
| { |
| store_release(&ci->online, 1); |
| } |
| |
| static inline void cpu_disable_dev(device_t dev) |
| { |
| dev->enabled = 0; |
| } |
| |
| static struct cpu_driver *locate_cpu_driver(uint32_t midr) |
| { |
| struct cpu_driver *cur; |
| |
| for (cur = cpu_drivers; cur != ecpu_drivers; cur++) { |
| const struct cpu_device_id *id_table = cur->id_table; |
| |
| for (; id_table->midr != CPU_ID_END; id_table++) { |
| if (id_table->midr == midr) |
| return cur; |
| } |
| } |
| return NULL; |
| } |
| |
| static int cpu_set_device_operations(device_t dev) |
| { |
| uint32_t midr; |
| struct cpu_driver *driver; |
| |
| midr = raw_read_midr_el1(); |
| driver = locate_cpu_driver(midr); |
| |
| if (driver == NULL) { |
| printk(BIOS_WARNING, "No CPU driver for MIDR %08x\n", midr); |
| return -1; |
| } |
| dev->ops = driver->ops; |
| return 0; |
| } |
| |
| static void init_this_cpu(void *arg) |
| { |
| struct cpu_info *ci = arg; |
| device_t dev = ci->cpu; |
| |
| cpu_set_device_operations(dev); |
| |
| if (dev->ops != NULL && dev->ops->init != NULL) { |
| dev->initialized = 1; |
| printk(BIOS_DEBUG, "%s init\n", dev_path(dev)); |
| dev->ops->init(dev); |
| } |
| } |
| |
| /* Fill in cpu_info structures according to device tree. */ |
| static void init_cpu_info(struct bus *bus) |
| { |
| device_t cur; |
| |
| for (cur = bus->children; cur != NULL; cur = cur->sibling) { |
| struct cpu_info *ci; |
| unsigned int id = cur->path.cpu.id; |
| |
| if (cur->path.type != DEVICE_PATH_CPU) |
| continue; |
| |
| /* IDs are currently mapped 1:1 with logical CPU numbers. */ |
| if (id >= CONFIG_MAX_CPUS) { |
| printk(BIOS_WARNING, |
| "CPU id %x too large. Disabling.\n", id); |
| cpu_disable_dev(cur); |
| continue; |
| } |
| |
| ci = cpu_info_for_cpu(id); |
| if (ci->cpu != NULL) { |
| printk(BIOS_WARNING, |
| "Duplicate ID %x in device tree.\n", id); |
| cpu_disable_dev(cur); |
| } |
| |
| ci->cpu = cur; |
| ci->id = cur->path.cpu.id; |
| } |
| |
| /* Mark current cpu online. */ |
| cpu_mark_online(cpu_info()); |
| } |
| |
| 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 or enabled devices. */ |
| if (!cpu_online(ci) || ci->cpu == NULL || !ci->cpu->enabled) |
| 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; |
| } |
| |
| 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); |
| } |
| |
| void arch_secondary_cpu_init(void) |
| { |
| struct cpu_info *ci = cpu_info(); |
| struct cpu_action_queue *q = &ci->action_queue; |
| |
| /* Mark this CPU online. */ |
| cpu_mark_online(ci); |
| |
| while (1) { |
| struct cpu_action *orig; |
| struct cpu_action action; |
| |
| orig = wait_for_action(q, &action); |
| |
| action_run(&action); |
| action_queue_complete(q, orig); |
| } |
| } |
| |
| void arch_initialize_cpus(device_t cluster, struct cpu_control_ops *cntrl_ops) |
| { |
| size_t max_cpus; |
| size_t i; |
| struct cpu_info *ci; |
| void (*entry)(void); |
| struct bus *bus; |
| |
| if (cluster->path.type != DEVICE_PATH_CPU_CLUSTER) { |
| printk(BIOS_ERR, |
| "CPU init failed. Device is not a CPU_CLUSTER: %s\n", |
| dev_path(cluster)); |
| return; |
| } |
| |
| bus = cluster->link_list; |
| entry = prepare_secondary_cpu_startup(); |
| |
| /* Initialize the cpu_info structures. */ |
| init_cpu_info(bus); |
| max_cpus = cntrl_ops->total_cpus(); |
| |
| if (max_cpus > CONFIG_MAX_CPUS) { |
| printk(BIOS_WARNING, |
| "max_cpus (%zu) exceeds CONFIG_MAX_CPUS (%zu).\n", |
| max_cpus, (size_t)CONFIG_MAX_CPUS); |
| max_cpus = CONFIG_MAX_CPUS; |
| } |
| |
| for (i = 0; i < max_cpus; i++) { |
| device_t dev; |
| struct cpu_action action; |
| |
| ci = cpu_info_for_cpu(i); |
| dev = ci->cpu; |
| |
| /* Disregard CPUs not in device tree. */ |
| if (dev == NULL) |
| continue; |
| |
| /* Skip disabled CPUs. */ |
| if (!dev->enabled) |
| continue; |
| |
| if (!cpu_online(ci)) { |
| /* Start the CPU. */ |
| printk(BIOS_DEBUG, "Starting CPU%x\n", ci->id); |
| if (cntrl_ops->start_cpu(ci->id, entry)) { |
| printk(BIOS_ERR, |
| "Failed to start CPU%x\n", ci->id); |
| continue; |
| } |
| /* Wait for CPU to come online. */ |
| while (!cpu_online(ci)); |
| printk(BIOS_DEBUG, "CPU%x online.\n", ci->id); |
| } |
| |
| /* Send it the init action. */ |
| action.run = init_this_cpu; |
| action.arg = ci; |
| action_run_on_cpu(ci, &action, 1); |
| } |
| } |