zephyr/drivers/bbram/bbram_npcx.c

121 lines
3.4 KiB
C

/*
* Copyright (c) 2021 Google Inc
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT nuvoton_npcx_bbram
#include <drivers/bbram.h>
#include <errno.h>
#include <sys/util.h>
#include <logging/log.h>
LOG_MODULE_REGISTER(bbram, CONFIG_BBRAM_LOG_LEVEL);
/** Device config */
struct bbram_npcx_config {
/** BBRAM base address */
uintptr_t base_addr;
/** BBRAM size (Unit:bytes) */
int size;
/** Status register base address */
uintptr_t status_reg_addr;
};
#define NPCX_STATUS_IBBR BIT(7)
#define NPCX_STATUS_VSBY BIT(1)
#define NPCX_STATUS_VCC1 BIT(0)
#define DRV_STATUS(dev) \
(*((volatile uint8_t *)((const struct bbram_npcx_config *)(dev)->config)->status_reg_addr))
static int get_bit_and_reset(const struct device *dev, int mask)
{
int result = DRV_STATUS(dev) & mask;
/* Clear the bit(s) */
DRV_STATUS(dev) = mask;
return result;
}
static int bbram_npcx_check_invalid(const struct device *dev)
{
return get_bit_and_reset(dev, NPCX_STATUS_IBBR);
}
static int bbram_npcx_check_standby_power(const struct device *dev)
{
return get_bit_and_reset(dev, NPCX_STATUS_VSBY);
}
static int bbram_npcx_check_power(const struct device *dev)
{
return get_bit_and_reset(dev, NPCX_STATUS_VCC1);
}
static int bbram_npcx_get_size(const struct device *dev, size_t *size)
{
const struct bbram_npcx_config *config = dev->config;
*size = config->size;
return 0;
}
static int bbram_npcx_read(const struct device *dev, size_t offset, size_t size,
uint8_t *data)
{
const struct bbram_npcx_config *config = dev->config;
if (size < 1 || offset + size > config->size || bbram_npcx_check_invalid(dev)) {
return -EFAULT;
}
bytecpy(data, ((uint8_t *)config->base_addr + offset), size);
return 0;
}
static int bbram_npcx_write(const struct device *dev, size_t offset, size_t size,
const uint8_t *data)
{
const struct bbram_npcx_config *config = dev->config;
if (size < 1 || offset + size > config->size || bbram_npcx_check_invalid(dev)) {
return -EFAULT;
}
bytecpy(((uint8_t *)config->base_addr + offset), data, size);
return 0;
}
static const struct bbram_driver_api bbram_npcx_driver_api = {
.check_invalid = bbram_npcx_check_invalid,
.check_standby_power = bbram_npcx_check_standby_power,
.check_power = bbram_npcx_check_power,
.get_size = bbram_npcx_get_size,
.read = bbram_npcx_read,
.write = bbram_npcx_write,
};
static int bbram_npcx_init(const struct device *dev)
{
ARG_UNUSED(dev);
return 0;
}
#define BBRAM_INIT(inst) \
static struct { \
} bbram_data_##inst; \
static const struct bbram_npcx_config bbram_cfg_##inst = { \
.base_addr = DT_INST_REG_ADDR_BY_NAME(inst, memory), \
.size = DT_INST_REG_SIZE_BY_NAME(inst, memory), \
.status_reg_addr = DT_INST_REG_ADDR_BY_NAME(inst, status), \
}; \
DEVICE_DT_INST_DEFINE(inst, bbram_npcx_init, NULL, &bbram_data_##inst, &bbram_cfg_##inst, \
PRE_KERNEL_1, CONFIG_BBRAM_INIT_PRIORITY, &bbram_npcx_driver_api);
DT_INST_FOREACH_STATUS_OKAY(BBRAM_INIT);