zephyr/drivers/mbox/mbox_esp32.c

271 lines
8.6 KiB
C

/*
* Copyright (c) 2024 Felipe Neves.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT espressif_mbox_esp32
#include "soc/dport_reg.h"
#include "soc/gpio_periph.h"
#include <stdint.h>
#include <string.h>
#include <zephyr/kernel.h>
#include <zephyr/device.h>
#include <zephyr/drivers/mbox.h>
#include <zephyr/drivers/interrupt_controller/intc_esp32.h>
#include <soc.h>
#include <zephyr/sys/atomic.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(mbox_esp32, CONFIG_MBOX_LOG_LEVEL);
#define ESP32_MBOX_LOCK_FREE_VAL 0xB33FFFFF
#define ESP32_MBOX_NOOP_VAL 0xFF
__packed struct esp32_mbox_control {
uint16_t dest_cpu_msg_id[2];
atomic_t lock;
};
struct esp32_mbox_memory {
volatile uint8_t *pro_cpu_shm;
volatile uint8_t *app_cpu_shm;
};
struct esp32_mbox_config {
int irq_source_pro_cpu;
int irq_priority_pro_cpu;
int irq_flags_pro_cpu;
int irq_source_app_cpu;
int irq_priority_app_cpu;
int irq_flags_app_cpu;
};
struct esp32_mbox_data {
mbox_callback_t cb;
void *user_data;
uint32_t this_core_id;
uint32_t other_core_id;
uint32_t shm_size;
struct esp32_mbox_memory shm;
struct esp32_mbox_control *control;
};
IRAM_ATTR static void esp32_mbox_isr(const struct device *dev)
{
struct esp32_mbox_data *dev_data = (struct esp32_mbox_data *)dev->data;
struct mbox_msg msg;
uint32_t core_id = dev_data->this_core_id;
/* clear interrupt flag */
if (core_id == 0) {
#if defined(CONFIG_SOC_SERIES_ESP32)
DPORT_WRITE_PERI_REG(DPORT_CPU_INTR_FROM_CPU_0_REG, 0);
#elif defined(CONFIG_SOC_SERIES_ESP32S3)
WRITE_PERI_REG(SYSTEM_CPU_INTR_FROM_CPU_0_REG, 0);
#endif
} else {
#if defined(CONFIG_SOC_SERIES_ESP32)
DPORT_WRITE_PERI_REG(DPORT_CPU_INTR_FROM_CPU_1_REG, 0);
#elif defined(CONFIG_SOC_SERIES_ESP32S3)
WRITE_PERI_REG(SYSTEM_CPU_INTR_FROM_CPU_1_REG, 0);
#endif
}
/* first of all take the ownership of the shared memory */
while (!atomic_cas(&dev_data->control->lock, ESP32_MBOX_LOCK_FREE_VAL,
dev_data->this_core_id))
;
if (dev_data->cb) {
/* For ESP32 soft mbox driver, the message parameter of the callback holds
* the portion of shared memory that belongs to the current core ID.
*/
msg.data = (dev_data->this_core_id == 0) ? (const void *)dev_data->shm.pro_cpu_shm
: (const void *)dev_data->shm.app_cpu_shm;
msg.size = dev_data->shm_size;
dev_data->cb(dev, dev_data->other_core_id, dev_data->user_data, &msg);
}
/* unlock the shared memory */
atomic_set(&dev_data->control->lock, ESP32_MBOX_LOCK_FREE_VAL);
}
static int esp32_mbox_send(const struct device *dev, mbox_channel_id_t channel,
const struct mbox_msg *msg)
{
ARG_UNUSED(msg);
struct esp32_mbox_data *dev_data = (struct esp32_mbox_data *)dev->data;
if (channel > 0xFFFF) {
LOG_ERR("Invalid channel");
return -EINVAL;
}
uint32_t key = irq_lock();
/* try to lock the shared memory */
while (!atomic_cas(&dev_data->control->lock, ESP32_MBOX_LOCK_FREE_VAL,
dev_data->this_core_id)) {
k_msleep(1);
}
/* Only the lower 16bits of id are used */
dev_data->control->dest_cpu_msg_id[dev_data->other_core_id] = (uint16_t)(channel & 0xFFFF);
/* Generate interrupt in the remote core */
if (dev_data->this_core_id == 0) {
atomic_set(&dev_data->control->lock, ESP32_MBOX_LOCK_FREE_VAL);
LOG_DBG("Generating interrupt on remote CPU 1 from CPU 0");
#if defined(CONFIG_SOC_SERIES_ESP32)
DPORT_WRITE_PERI_REG(DPORT_CPU_INTR_FROM_CPU_1_REG, DPORT_CPU_INTR_FROM_CPU_1);
#elif defined(CONFIG_SOC_SERIES_ESP32S3)
WRITE_PERI_REG(SYSTEM_CPU_INTR_FROM_CPU_1_REG, SYSTEM_CPU_INTR_FROM_CPU_1);
#endif
} else {
atomic_set(&dev_data->control->lock, ESP32_MBOX_LOCK_FREE_VAL);
LOG_DBG("Generating interrupt on remote CPU 0 from CPU 1");
#if defined(CONFIG_SOC_SERIES_ESP32)
DPORT_WRITE_PERI_REG(DPORT_CPU_INTR_FROM_CPU_0_REG, DPORT_CPU_INTR_FROM_CPU_0);
#elif defined(CONFIG_SOC_SERIES_ESP32S3)
WRITE_PERI_REG(SYSTEM_CPU_INTR_FROM_CPU_0_REG, SYSTEM_CPU_INTR_FROM_CPU_0);
#endif
}
irq_unlock(key);
return 0;
}
static int esp32_mbox_register_callback(const struct device *dev, mbox_channel_id_t channel,
mbox_callback_t cb, void *user_data)
{
ARG_UNUSED(channel);
struct esp32_mbox_data *data = (struct esp32_mbox_data *)dev->data;
if (!cb) {
LOG_ERR("Must provide callback");
return -EINVAL;
}
uint32_t key = irq_lock();
data->cb = cb;
data->user_data = user_data;
irq_unlock(key);
return 0;
}
static int esp32_mbox_mtu_get(const struct device *dev)
{
struct esp32_mbox_data *data = (struct esp32_mbox_data *)dev->data;
return data->shm_size;
}
static uint32_t esp32_mbox_max_channels_get(const struct device *dev)
{
ARG_UNUSED(dev);
return 1;
}
static int esp32_mbox_set_enabled(const struct device *dev, mbox_channel_id_t channel, bool enable)
{
/* The esp32 MBOX is always enabled
* but rpmsg backend needs MBOX set enabled to be
* implemented so just return success here
*/
ARG_UNUSED(dev);
ARG_UNUSED(enable);
ARG_UNUSED(channel);
return 0;
}
static int esp32_mbox_init(const struct device *dev)
{
struct esp32_mbox_data *data = (struct esp32_mbox_data *)dev->data;
struct esp32_mbox_config *cfg = (struct esp32_mbox_config *)dev->config;
int ret;
data->this_core_id = esp_core_id();
data->other_core_id = (data->this_core_id == 0) ? 1 : 0;
LOG_DBG("Size of MBOX shared memory: %d", data->shm_size);
LOG_DBG("Address of PRO_CPU MBOX shared memory: %p", data->shm.pro_cpu_shm);
LOG_DBG("Address of APP_CPU MBOX shared memory: %p", data->shm.app_cpu_shm);
LOG_DBG("Address of MBOX control structure: %p", data->control);
/* pro_cpu is responsible to initialize the lock of shared memory */
if (data->this_core_id == 0) {
ret = esp_intr_alloc(cfg->irq_source_pro_cpu,
ESP_PRIO_TO_FLAGS(cfg->irq_priority_pro_cpu) |
ESP_INT_FLAGS_CHECK(cfg->irq_flags_pro_cpu) |
ESP_INTR_FLAG_IRAM,
(intr_handler_t)esp32_mbox_isr, (void *)dev, NULL);
atomic_set(&data->control->lock, ESP32_MBOX_LOCK_FREE_VAL);
} else {
/* app_cpu wait for initialization from pro_cpu, then takes it,
* after that releases
*/
ret = esp_intr_alloc(cfg->irq_source_app_cpu,
ESP_PRIO_TO_FLAGS(cfg->irq_priority_app_cpu) |
ESP_INT_FLAGS_CHECK(cfg->irq_flags_app_cpu) |
ESP_INTR_FLAG_IRAM,
(intr_handler_t)esp32_mbox_isr, (void *)dev, NULL);
LOG_DBG("Waiting CPU0 to sync");
while (!atomic_cas(&data->control->lock, ESP32_MBOX_LOCK_FREE_VAL,
data->this_core_id))
;
atomic_set(&data->control->lock, ESP32_MBOX_LOCK_FREE_VAL);
LOG_DBG("Synchronization done");
}
return ret;
}
static const struct mbox_driver_api esp32_mbox_driver_api = {
.send = esp32_mbox_send,
.register_callback = esp32_mbox_register_callback,
.mtu_get = esp32_mbox_mtu_get,
.max_channels_get = esp32_mbox_max_channels_get,
.set_enabled = esp32_mbox_set_enabled,
};
#define ESP32_MBOX_SHM_SIZE_BY_IDX(idx) DT_INST_PROP(idx, shared_memory_size)
#define ESP32_MBOX_SHM_ADDR_BY_IDX(idx) DT_REG_ADDR(DT_PHANDLE(DT_DRV_INST(idx), shared_memory))
#define ESP32_MBOX_INIT(idx) \
static struct esp32_mbox_config esp32_mbox_device_cfg_##idx = { \
.irq_source_pro_cpu = DT_INST_IRQ_BY_IDX(idx, 0, irq), \
.irq_priority_pro_cpu = DT_INST_IRQ_BY_IDX(idx, 0, priority), \
.irq_flags_pro_cpu = DT_INST_IRQ_BY_IDX(idx, 0, flags), \
.irq_source_app_cpu = DT_INST_IRQ_BY_IDX(idx, 1, irq), \
.irq_priority_app_cpu = DT_INST_IRQ_BY_IDX(idx, 1, priority), \
.irq_flags_app_cpu = DT_INST_IRQ_BY_IDX(idx, 1, flags), \
}; \
static struct esp32_mbox_data esp32_mbox_device_data_##idx = { \
.shm_size = ESP32_MBOX_SHM_SIZE_BY_IDX(idx), \
.shm.pro_cpu_shm = (uint8_t *)ESP32_MBOX_SHM_ADDR_BY_IDX(idx), \
.shm.app_cpu_shm = (uint8_t *)ESP32_MBOX_SHM_ADDR_BY_IDX(idx) + \
ESP32_MBOX_SHM_SIZE_BY_IDX(idx) / 2, \
.control = (struct esp32_mbox_control *)DT_INST_REG_ADDR(idx), \
}; \
DEVICE_DT_INST_DEFINE(idx, &esp32_mbox_init, NULL, &esp32_mbox_device_data_##idx, \
&esp32_mbox_device_cfg_##idx, PRE_KERNEL_2, \
CONFIG_KERNEL_INIT_PRIORITY_DEFAULT, &esp32_mbox_driver_api);
DT_INST_FOREACH_STATUS_OKAY(ESP32_MBOX_INIT);