blob: 713acc04adc08c56ed2c07b08dd4e6be949a91b7 [file] [log] [blame]
/*
* This file is part of the coreboot project.
*
* Copyright 2016 Rockchip 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.
*
*/
#include <device/mmio.h>
#include <assert.h>
#include <delay.h>
#include <soc/clock.h>
#include <soc/saradc.h>
#include <stdint.h>
#include <timer.h>
struct rk3399_saradc_regs {
u32 data;
u32 stas;
u32 ctrl;
u32 dly_pu_soc;
};
check_member(rk3399_saradc_regs, dly_pu_soc, 0xc);
struct rk3399_saradc_regs *rk3399_saradc = (void *)SARADC_BASE;
/* SARADC_STAS: conversion done */
#define ADC_STOP 0
/* SARADC_CTRL */
#define INT_EN (1 << 5)
#define ADC_PWR_CTRL (1 << 3)
#define ADC_CHN_SEL_MASK 7
#define ADC_CHN_SEL_SHIFT 0
/* SARADC_DATA, 10[0:9] bits */
#define DATA_MASK 0x3FF
#define SARADC_HZ (4*MHz)
#define SARADC_MAX_CHANNEL 6
#define SARADC_DELAY_PU (1 * 1000 * 1000 * 1000 / SARADC_HZ * 4)
u32 get_saradc_value(u32 chn)
{
u32 adc_value;
struct stopwatch sw;
assert(chn < SARADC_MAX_CHANNEL);
rkclk_configure_saradc(SARADC_HZ);
/* power down adc converter */
clrbits32(&rk3399_saradc->ctrl, ADC_PWR_CTRL);
/* select channel */
clrsetbits32(&rk3399_saradc->ctrl,
ADC_CHN_SEL_MASK << ADC_CHN_SEL_SHIFT,
chn << ADC_CHN_SEL_SHIFT);
/* power up */
setbits32(&rk3399_saradc->ctrl, ADC_PWR_CTRL);
udelay(SARADC_DELAY_PU);
stopwatch_init_msecs_expire(&sw, 10);
do {
if (read32(&rk3399_saradc->stas) == ADC_STOP) {
adc_value = read32(&rk3399_saradc->data) & DATA_MASK;
return adc_value;
}
} while (!stopwatch_expired(&sw));
return -1;
}