arch/risc-v/espressif: Add LPSPI and SPI3 support

[eren-terzioglu]

Summary

• Docs/platforms/risc-v: Add LPSPI and SPI3 docs for esp32[-p4]

Add LPSPI and SPI3 docs for esp32p4

• boards/risc-v/esp32p4: Add LPSPI and SPI3 board support

Add LPSPI and SPI3 board support for esp32[-p4]

• arch/risc-v/espressif: Add LPSPI and SPI3 support

Add LPSPI and SPI3 support for esp32[-p4]

Impact

Impact on user: Yes, LPSPI and SPI3 can be used for esp32p4

Impact on build: No

Impact on hardware: Yes, missing hardware support added

Impact on documentation: Yes, related docs added

Impact on security: No

Impact on compatibility: No

Testing

esp32p4-function-ev-board:spi config used with these options:

CONFIG_ESPRESSIF_USE_LP_CORE
CONFIG_ESPRESSIF_LPSPI0

Building

Command to build:

make distclean && ./tools/configure.sh esp32p4-function-ev-board:spi && kconfig-tweak -e CONFIG_ESPRESSIF_USE_LP_CORE && kconfig-tweak -e CONFIG_ESPRESSIF_LPSPI && make olddefconfig && make olddefconfig && make -j && make download ESPTOOL_PORT=/dev/ttyUSB0

Running

Testing LPSPI

ULP code snippet

#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include "ulp_lp_core_spi.h"
#include "ulp_lp_core_utils.h"
#include "ulp_lp_core_print.h"

int main (void)
{
    uint8_t data = 0x55;
    lp_spi_transaction_t trans_desc = {
        .tx_buffer = &data,
        .tx_length = 1,
        .address = 0,
        .address_bits = 0,
    };

    esp_err_t err = lp_core_lp_spi_master_transfer(&trans_desc, LP_SPI_TRANS_WAIT_FOREVER);
    if(err != ESP_OK) {
        DEBUG_LOG("Failed to write register: 0x%X, with data = 0x%X\n", reg_addr, data);
        abort();
    }

    return 0;
}

Output needs to be checked with a logic analyzer. Default pins are:

Pin Name	Pin Number
MOSI	7
MISO	6
CLK	8
CS	4

Testing SPI3

MOSI and MISO pins connected with a cable (GPIO21-GPIO27) and run this spi exch -b 3 AB command

Results

nsh> spi exch -b 3 AB
Sending:	AB 
Received:	AB