arm64: add devicetree based CPU startup
This adds SMP bring up support for arm64 cpus. It's
reliant on DEVICE_PATH_CPU devices in the devicetree.
Then for each enabled device it attempts to start then
initialize each CPU. Additionally, there is a cpu_action
construct which allows for running actions on an individual
cpu.
BUG=chrome-os-partner:31761
BRANCH=None
TEST=Booted both cores on ryu into linux.
Change-Id: I3e42fb668034c27808d706427a26be1558ad2af1
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: a733fd566a8e5793da5ff28f9c16c213f411372e
Original-Change-Id: I407eabd0b6985fc4e86de57a9e034548ec8f3d81
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/216925
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9042
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
diff --git a/src/arch/arm64/cpu.c b/src/arch/arm64/cpu.c
index 0f9f361..f1733ea 100644
--- a/src/arch/arm64/cpu.c
+++ b/src/arch/arm64/cpu.c
@@ -17,12 +17,332 @@
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
*/
+#include <stdint.h>
#include <stdlib.h>
-#include <arch/cpu.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_infos[smp_processor_id()];
+ 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);
+ }
}