Files
hackrf/firmware/common/ice40_spi.c

126 lines
3.6 KiB
C

/*
* Copyright 2024 Great Scott Gadgets <info@greatscottgadgets.com>
*
* This file is part of HackRF.
*
* 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; either version 2, or (at your option)
* any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#include "ice40_spi.h"
#include <libopencm3/lpc43xx/scu.h>
#include "hackrf_core.h"
#include "lz4_buf.h"
#include "delay.h"
void ice40_spi_target_init(ice40_spi_driver_t* const drv)
{
/* Configure SSP1 Peripheral and relevant FPGA pins. */
scu_pinmux(SCU_SSP1_CIPO, (SCU_SSP_IO | SCU_CONF_FUNCTION5));
scu_pinmux(SCU_SSP1_COPI, (SCU_SSP_IO | SCU_CONF_FUNCTION5));
scu_pinmux(SCU_SSP1_SCK, (SCU_SSP_IO | SCU_CONF_FUNCTION1));
scu_pinmux(SCU_PINMUX_FPGA_CRESET, SCU_GPIO_NOPULL | SCU_CONF_FUNCTION0);
scu_pinmux(SCU_PINMUX_FPGA_CDONE, SCU_GPIO_PUP | SCU_CONF_FUNCTION4);
scu_pinmux(SCU_PINMUX_FPGA_SPI_CS, SCU_GPIO_NOPULL | SCU_CONF_FUNCTION0);
/* Configure GPIOs as inputs or outputs as needed. */
gpio_clear(drv->gpio_creset);
gpio_output(drv->gpio_creset);
gpio_input(drv->gpio_cdone);
// select is configured in SSP code
}
uint8_t ice40_spi_read(ice40_spi_driver_t* const drv, uint8_t r)
{
uint8_t value[3] = {r & 0x7F, 0, 0};
spi_bus_transfer(drv->bus, value, 3);
return value[2];
}
void ice40_spi_write(ice40_spi_driver_t* const drv, uint8_t r, uint16_t v)
{
uint8_t value[3] = {(r & 0x7F) | 0x80, v, 0};
spi_bus_transfer(drv->bus, value, 3);
}
static void spi_ssp1_wait_for_tx_fifo_not_full(void)
{
while ((SSP_SR(SSP1_BASE) & SSP_SR_TNF) == 0) {}
}
static void spi_ssp1_wait_for_rx_fifo_not_empty(void)
{
while ((SSP_SR(SSP1_BASE) & SSP_SR_RNE) == 0) {}
}
static void spi_ssp1_wait_for_not_busy(void)
{
while (SSP_SR(SSP1_BASE) & SSP_SR_BSY) {}
}
static uint32_t spi_ssp1_transfer_word(const uint32_t data)
{
spi_ssp1_wait_for_tx_fifo_not_full();
SSP_DR(SSP1_BASE) = data;
spi_ssp1_wait_for_not_busy();
spi_ssp1_wait_for_rx_fifo_not_empty();
return SSP_DR(SSP1_BASE);
}
bool ice40_spi_syscfg_program(
ice40_spi_driver_t* const drv,
size_t (*read_block_cb)(void* ctx, uint8_t* buffer),
void* read_ctx)
{
// Drive CRESET_B = 0, SPI_SS = 0, SPI_SCK = 1.
gpio_clear(drv->gpio_creset);
gpio_clear(drv->gpio_select);
// Wait a minimum of 200 ns.
delay_us_at_mhz(1, 204 / 4); // 250 ns.
// Release CRESET_B or drive CRESET_B = 1.
gpio_set(drv->gpio_creset);
// Wait a minimum of 1200 μs to clear internal configuration memory.
// Testing showed us that we need to wait longer. Let's wait 1800 μs.
delay_us_at_mhz(1800, 204);
// Set SPI_SS = 1, Send 8 dummy clocks.
gpio_set(drv->gpio_select);
spi_ssp1_transfer_word(0);
// Send configuration image serially on SPI_SI to iCE40, most-significant bit
// first, on falling edge of SPI_SCK.
gpio_clear(drv->gpio_select);
for (;;) {
size_t read_sz = read_block_cb(read_ctx, lz4_out_buf);
if (read_sz == 0)
break;
for (size_t j = 0; j < read_sz; j++) {
spi_ssp1_transfer_word(lz4_out_buf[j]);
}
}
// Wait for 100 clocks cycles for CDONE to go high.
gpio_set(drv->gpio_select);
for (size_t j = 0; j < 13; j++) {
spi_ssp1_transfer_word(0);
}
return gpio_read(drv->gpio_cdone);
}