Projet_SETI_RISC-V/neorv32/sw/example/demo_slink/main.c
2023-03-06 14:48:14 +01:00

202 lines
8.3 KiB
C

// #################################################################################################
// # << NEORV32 - SLINK Demo Program >> #
// # ********************************************************************************************* #
// # BSD 3-Clause License #
// # #
// # Copyright (c) 2023, Stephan Nolting. All rights reserved. #
// # #
// # Redistribution and use in source and binary forms, with or without modification, are #
// # permitted provided that the following conditions are met: #
// # #
// # 1. Redistributions of source code must retain the above copyright notice, this list of #
// # conditions and the following disclaimer. #
// # #
// # 2. Redistributions in binary form must reproduce the above copyright notice, this list of #
// # conditions and the following disclaimer in the documentation and/or other materials #
// # provided with the distribution. #
// # #
// # 3. Neither the name of the copyright holder nor the names of its contributors may be used to #
// # endorse or promote products derived from this software without specific prior written #
// # permission. #
// # #
// # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS #
// # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF #
// # MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE #
// # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, #
// # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE #
// # GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED #
// # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING #
// # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED #
// # OF THE POSSIBILITY OF SUCH DAMAGE. #
// # ********************************************************************************************* #
// # The NEORV32 Processor - https://github.com/stnolting/neorv32 (c) Stephan Nolting #
// #################################################################################################
/**********************************************************************//**
* @file demo_slink/main.c
* @author Stephan Nolting
* @brief SLINK demo program.
**************************************************************************/
#include <neorv32.h>
#include <string.h>
/**********************************************************************//**
* @name User configuration
**************************************************************************/
/**@{*/
/** UART BAUD rate */
#define BAUD_RATE 19200
/**@}*/
// Prototypes
void slink_rx_firq_handler(void);
void slink_tx_firq_handler(void);
uint32_t xorshift32(void);
/**********************************************************************//**
* Simple SLINK demo program.
*
* @note This program requires the UART0 and the SLINK to be synthesized.
*
* @return =! 0 if execution failed.
**************************************************************************/
int main() {
int i;
uint32_t slink_data;
int slink_status;
// capture all exceptions and give debug info via UART0
neorv32_rte_setup();
// setup UART0 at default baud rate, no parity bits, no HW flow control
neorv32_uart0_setup(BAUD_RATE, PARITY_NONE, FLOW_CONTROL_NONE);
// check if UART0 unit is implemented at all
if (neorv32_uart0_available() == 0) {
return -1; // abort if not implemented
}
// intro
neorv32_uart0_printf("\n<<< SLINK Demo Program >>>\n\n");
// check if SLINK is implemented at all
if (neorv32_slink_available() == 0) {
neorv32_uart0_printf("ERROR! SLINK module not implemented.");
return -1;
}
// show SLINK hardware configuration
neorv32_uart0_printf("# SLINK RX channels: %u (%u FIFO entries each)\n"
"# SLINK TX channels: %u (%u FIFO entries each)\n",
neorv32_slink_get_link_num(0),
neorv32_slink_get_fifo_depth(0),
neorv32_slink_get_link_num(1),
neorv32_slink_get_fifo_depth(1));
neorv32_uart0_printf("\nNOTE: This demo program uses SLINK RX/TX channels 0 only.\n\n");
// reset and enable SLINK module
neorv32_slink_setup((0b10 << (SLINK_IRQ_RX_LSB + 2*0)) | // RX link 0: IRQ if FIFO becomes not empty
(0b11 << (SLINK_IRQ_TX_LSB + 2*0))); // TX link 0: IRQ if FIFO becomes less than half full
// NEORV32 runtime environment: install SLINK FIRQ handlers
neorv32_rte_handler_install(SLINK_RX_RTE_ID, slink_rx_firq_handler);
neorv32_rte_handler_install(SLINK_TX_RTE_ID, slink_tx_firq_handler);
neorv32_cpu_csr_set(CSR_MIE, 1 << SLINK_RX_FIRQ_ENABLE); // enable SLINK RX FIRQ
neorv32_cpu_csr_set(CSR_MIE, 1 << SLINK_TX_FIRQ_ENABLE); // enable SLINK RX FIRQ
neorv32_cpu_csr_set(CSR_MSTATUS, 1 << CSR_MSTATUS_MIE); // enable machine-mode interrupts
// do some demo transmissions
neorv32_uart0_printf("-------- TX Demo --------\n");
for (i=0; i<6; i++) { // try to send 6 data words
slink_data = xorshift32();
neorv32_uart0_printf("%i: SLINK TX 0x%x via link 0... ", i, slink_data);
if (i == 3) {
neorv32_uart0_printf("[set END-OF-PACKET] ");
slink_status = neorv32_slink_tx(0, slink_data, 1); // do a "end of packet" transmission (set LST high)
}
else {
slink_status = neorv32_slink_tx(0, slink_data, 0); // "normal" transmission
}
if (slink_status == 0) { // successful?
neorv32_uart0_printf("ok\n");
}
else {
neorv32_uart0_printf("fail; FIFO full\n");
}
}
// check the RX link
neorv32_uart0_printf("\n-------- RX Demo --------\n");
for (i=0; i<6; i++) { // try to read 6 data words
slink_data = 0;
neorv32_uart0_printf("%i: SLINK RX link 0... ", i);
slink_status = neorv32_slink_rx(0, &slink_data);
if (slink_status == 0) {
neorv32_uart0_printf("received 0x%x\n", slink_data);
}
else if (slink_status == 1) {
neorv32_uart0_printf("received 0x%x [END-OF-PACKET]\n", slink_data);
}
else { // == -1
neorv32_uart0_printf("no data available\n");
}
}
neorv32_uart0_printf("\nProgram execution completed.\n");
return 0;
}
/**********************************************************************//**
* SLINK RX interrupt handler.
**************************************************************************/
void slink_rx_firq_handler(void) {
neorv32_cpu_csr_write(CSR_MIP, ~(1 << SLINK_RX_FIRQ_PENDING)); // ack FIRQ
neorv32_uart0_printf(" <<SLINK RX IRQ!>> ");
}
/**********************************************************************//**
* SLINK TX interrupt handler.
**************************************************************************/
void slink_tx_firq_handler(void) {
neorv32_cpu_csr_write(CSR_MIP, ~(1 << SLINK_TX_FIRQ_PENDING)); // ack FIRQ
neorv32_uart0_printf(" <<SLINK TX IRQ!>> ");
}
/**********************************************************************//**
* Simple pseudo random number generator.
*
* @return Random number.
**************************************************************************/
uint32_t xorshift32(void) {
static uint32_t x32 = 314159265;
x32 ^= x32 << 13;
x32 ^= x32 >> 17;
x32 ^= x32 << 5;
return x32;
}