1/* 2 * Copyright 2017, Data61 3 * Commonwealth Scientific and Industrial Research Organisation (CSIRO) 4 * ABN 41 687 119 230. 5 * 6 * This software may be distributed and modified according to the terms of 7 * the BSD 2-Clause license. Note that NO WARRANTY is provided. 8 * See "LICENSE_BSD2.txt" for details. 9 * 10 * @TAG(DATA61_BSD) 11 */ 12 13#include <stdint.h> 14#include <platsupport/io.h> 15#include <platsupport/tmu.h> 16#include "xadc.h" 17 18/* Macros for converting from the raw sensor value into degrees kelvin. 19 * For a full description of this process, see 20 * 7 Series FPGAs and Zynq-7000 All Programmable SoC XADC 21 * Dual 12-bit 1 MSPS Analog-to-Digital Converter User Guide, 22 * CH. 2: Analog-to-Digital Converter, Temperature Sensor (p32) 23 */ 24 25/* The temperature is encoded in the 12 MSBs of 16 LSBs of the reported value */ 26#define TEMPERATURE_RAW_TO_CODE(x) (((x) & MASK(16)) >> 4u) 27 28/* Converts a word representation of a temperature obtained from the 29 * temperature sensor into degrees kelvin */ 30#define TEMPERATURE_RAW_TO_MILLIKELVIN(x) \ 31 ((TEMPERATURE_RAW_TO_CODE((x)) * 503975) / 4096) 32 33static uint32_t get_raw_temperature(ps_tmu_t* tmu) { 34 return xadc_read_register(XADC_ADDRESS_TEMPERATURE); 35} 36 37static temperature_t get_temperature_millikelvin(ps_tmu_t* tmu) { 38 return TEMPERATURE_RAW_TO_MILLIKELVIN(get_raw_temperature(tmu)); 39} 40 41int ps_tmu_init(enum tmu_id id, ps_io_ops_t* ops, ps_tmu_t* dev) { 42 43 xadc_init(ops); 44 45 dev->get_temperature = get_temperature_millikelvin; 46 dev->get_raw_temperature = get_raw_temperature; 47 48 return 0; 49} 50