zephyr/drivers/rtc/rtc_dw.c

221 lines
5.2 KiB
C

/*
* Copyright (c) 2015 Intel Corporation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <nanokernel.h>
#include <sys_io.h>
#include <stdio.h>
#include <rtc.h>
#include <init.h>
#include <clock_control.h>
#include "board.h"
#include "rtc_dw.h"
#define RTC_CLK_DIV_DEF_MASK (0xFFFFFF83)
#define CCU_RTC_CLK_DIV_EN (2)
#ifdef RTC_DW_INT_MASK
static inline void _rtc_dw_int_unmask(void)
{
sys_write32(sys_read32(RTC_DW_INT_MASK) & INT_UNMASK_IA,
RTC_DW_INT_MASK);
}
#else
#define _rtc_dw_int_unmask()
#endif
#ifdef CONFIG_RTC_DW_CLOCK_GATE
static inline void _rtc_dw_clock_config(struct device *dev)
{
char *drv = CONFIG_RTC_DW_CLOCK_GATE_DRV_NAME;
struct device *clk;
clk = device_get_binding(drv);
if (clk) {
struct rtc_dw_runtime *context = dev->driver_data;
context->clock = clk;
}
}
static inline void _rtc_dw_clock_on(struct device *dev)
{
struct rtc_dw_dev_config *config = dev->config->config_info;
struct rtc_dw_runtime *context = dev->driver_data;
clock_control_on(context->clock, config->clock_data);
}
static inline void _rtc_dw_clock_off(struct device *dev)
{
struct rtc_dw_dev_config *config = dev->config->config_info;
struct rtc_dw_runtime *context = dev->driver_data;
clock_control_off(context->clock, config->clock_data);
}
#else
#define _rtc_dw_clock_config(...)
#define _rtc_dw_clock_on(...)
#define _rtc_dw_clock_off(...)
#endif
static void rtc_dw_set_div(const enum clk_rtc_div div)
{
/* set default division mask */
uint32_t reg =
sys_read32(CLOCK_SYSTEM_CLOCK_CONTROL) & RTC_CLK_DIV_DEF_MASK;
reg |= (div << CCU_RTC_CLK_DIV_OFFSET);
sys_write32(reg, CLOCK_SYSTEM_CLOCK_CONTROL);
/* CLK Div en bit must be written from 0 -> 1 to apply new value */
sys_set_bit(CLOCK_SYSTEM_CLOCK_CONTROL, CCU_RTC_CLK_DIV_EN);
}
/**
* @brief Function to enable clock gating for the RTC
* @return N/A
*/
static void rtc_dw_enable(struct device *dev)
{
_rtc_dw_clock_on(dev);
}
/**
* @brief Function to disable clock gating for the RTC
* @return N/A
*/
static void rtc_dw_disable(struct device *dev)
{
_rtc_dw_clock_off(dev);
}
/**
* @brief RTC alarm ISR
*
* calls a user defined callback
*
* @return N/A
*/
void rtc_dw_isr(void *arg)
{
struct device *dev = arg;
struct rtc_dw_dev_config *rtc_dev = dev->config->config_info;
struct rtc_dw_runtime *context = dev->driver_data;
/* Disable RTC interrupt */
sys_clear_bit(rtc_dev->base_address + RTC_CCR, 0);
if (context->rtc_dw_cb_fn) {
context->rtc_dw_cb_fn(dev);
}
/* clear interrupt */
sys_read32(rtc_dev->base_address + RTC_EOI);
}
/**
* @brief Sets an RTC alarm
* @param alarm_val Alarm value
* @return 0 on success
*/
static int rtc_dw_set_alarm(struct device *dev, const uint32_t alarm_val)
{
struct rtc_dw_dev_config *rtc_dev = dev->config->config_info;
sys_set_bit(rtc_dev->base_address + RTC_CCR, 0);
sys_write32(alarm_val, rtc_dev->base_address + RTC_CMR);
return 0;
}
/**
* @brief Function to configure the RTC
* @param config pointer to a RTC configuration structure
* @return 0 on success
*/
static int rtc_dw_set_config(struct device *dev, struct rtc_config *config)
{
struct rtc_dw_dev_config *rtc_dev = dev->config->config_info;
struct rtc_dw_runtime *context = dev->driver_data;
/* Set RTC divider - 32768 / 32.768 khz = 1 second. */
rtc_dw_set_div(RTC_DIVIDER);
/* set initial RTC value */
sys_write32(config->init_val, rtc_dev->base_address + RTC_CLR);
/* clear any pending interrupts */
sys_read32(rtc_dev->base_address + RTC_EOI);
context->rtc_dw_cb_fn = config->cb_fn;
if (config->alarm_enable) {
rtc_dw_set_alarm(dev, config->alarm_val);
} else {
sys_clear_bit(rtc_dev->base_address + RTC_CCR, 0);
}
return 0;
}
/**
* @brief Read current RTC value
* @return current rtc value
*/
static uint32_t rtc_dw_read(struct device *dev)
{
struct rtc_dw_dev_config *rtc_dev = dev->config->config_info;
return sys_read32(rtc_dev->base_address + RTC_CCVR);
}
static struct rtc_driver_api api_funcs = {
.set_config = rtc_dw_set_config,
.read = rtc_dw_read,
.enable = rtc_dw_enable,
.disable = rtc_dw_disable,
.set_alarm = rtc_dw_set_alarm,
};
int rtc_dw_init(struct device *dev);
struct rtc_dw_runtime rtc_runtime;
struct rtc_dw_dev_config rtc_dev = {
.base_address = RTC_DW_BASE_ADDR,
#ifdef CONFIG_RTC_DW_CLOCK_GATE
.clock_data = UINT_TO_POINTER(CONFIG_RTC_DW_CLOCK_GATE_SUBSYS),
#endif
};
DEVICE_AND_API_INIT(rtc, CONFIG_RTC_DRV_NAME, &rtc_dw_init,
&rtc_runtime, &rtc_dev,
SECONDARY, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
&api_funcs);
int rtc_dw_init(struct device *dev)
{
IRQ_CONNECT(RTC_DW_IRQ, CONFIG_RTC_DW_IRQ_PRI, rtc_dw_isr,
DEVICE_GET(rtc), 0);
irq_enable(RTC_DW_IRQ);
_rtc_dw_int_unmask();
_rtc_dw_clock_config(dev);
return 0;
}