fiatlux/firmware/bus.cpp

#include "bus.h"
#include "esp/gpio.h"

#include <esp/spi.h>
#include "log.h"

uint32_t spi_transfer_32_duplex(uint8_t bus, uint32_t val) {
    uint32_t out = val;
    uint32_t in;
    spi_transfer(bus, &out, &in, 1, SPI_32BIT);
    return in;
}

uint16_t spi_transfer_16_duplex(uint8_t bus, uint32_t val) {
    uint16_t out = val;
    uint16_t in;
    spi_transfer(bus, &out, &in, 1, SPI_16BIT);
    return in;
}

void reset_bus() {
    gpio_write(4, false);
    for (volatile int k = 0; k < 128; ++k);
    gpio_write(4, true);
}

void bus_init() {
    gpio_write(4, false);
    for (volatile int k = 0; k < 512 * 2; ++k);
    gpio_write(4, true);
    gpio_enable(4, GPIO_OUT_OPEN_DRAIN);
    gpio_write(4, true);
    for (volatile int k = 0; k < 512 * 4; ++k);

    spi_init(1, SPI_MODE0, SPI_FREQ_DIV_2M, true, SPI_BIG_ENDIAN, false);
}

uint16_t bus_transfer_msg(uint8_t addr, uint16_t dat) {
    union {
        struct {
            unsigned dat: 12;
            unsigned addr: 4;
        } __attribute__((packed));
        uint16_t _;
    } frame = {._=0};

    frame.addr = addr;
    frame.dat = dat;
    spi_transfer_16_duplex(1, frame._);
    for (volatile int k = 0; k < 512 * 2; ++k);
    uint16_t reply = spi_transfer_16_duplex(1, 0x0000);
    for (volatile int k = 0; k < 512 * 2; ++k);
    return reply;
}

bool bus_transfer_msg_arr(uint8_t addr, uint16_t* dat, uint8_t len) {
    union {
        struct {
            unsigned dat: 12;
            unsigned addr: 4;
        } __attribute__((packed));
        uint16_t _;
    } frame = {._=0};

    uint16_t last_frame = 0x0000;
    uint16_t reply = 0x0000;
    uint8_t error_count = 0;

    for (int i = 0; i < len; ++i) {

        frame.addr = addr + i;
        frame.dat = dat[i];

        reply = spi_transfer_16_duplex(1, frame._);

        if(reply != last_frame && i != 0)
            error_count++;

        if(0){
            syslog(" > ");
            syslog_i32(frame._);
            syslog(" < ");
            syslog_i32(reply);
            syslog(" =? ");
            syslog_i32(last_frame);
            syslog("\n");
        }

        last_frame = frame._;

        for (volatile int k = 0; k < 512 * 2; ++k);
    }

    reply = spi_transfer_16_duplex(1, 0x0000);
    if(reply != last_frame)
        error_count++;

    if(0){
        syslog(" > ");
        syslog_i32(frame._);
        syslog(" < ");
        syslog_i32(reply);
        syslog(" =? ");
        syslog_i32(last_frame);
        syslog("\n");
    }

    return error_count == 0;
}

uint16_t bus_get_version() {
    return bus_transfer_msg(15, 0);
}

bool bus_ping() {
    return bus_get_version() == 0x002a;
}