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/*
* 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 <boardid.h>
#include <console/console.h>
#include <stdlib.h>
#include <soc/saradc.h>
/*
* ID info:
* ID : Volts : ADC value : Bucket
* == ===== ========= ======
* 0 : 0.074V: 37.888 : 0 - <=82
* 1 : 0.211V: 108.032 : 82- <=136
* 2 : 0.319V: 163.328 : 136-<=191
* 3 : 0.427V: 218.624 : 191-<=248
* 4 : 0.542V: 277.504 : 248-<=309
* 5 : 0.666V: 340.992 : 309-<=370
* 6 : 0.781V: 399.872 : 370- 512
*/
static const int id_readings[] = { 82, 136, 191, 248, 309, 370, 512 };
static int cached_board_id = -1;
static int cached_ram_id = -1;
static uint32_t get_index(uint32_t channel, int *cached_id)
{
int i;
int adc_reading;
if (*cached_id != -1)
return *cached_id;
adc_reading = get_saradc_value(channel);
for (i = 0; i < ARRAY_SIZE(id_readings); i++) {
if (adc_reading <= id_readings[i]) {
printk(BIOS_DEBUG, "ADC reading %d, ID %d\n",
adc_reading, i);
*cached_id = i;
return i;
}
}
printk(BIOS_DEBUG, "ERROR: Unmatched ADC reading of %d\n", adc_reading);
return 0;
}
uint8_t board_id(void)
{
return get_index(1, &cached_board_id);
}
uint32_t ram_code(void)
{
return get_index(0, &cached_ram_id);
}
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