NRF52840DK SPI Flash (w25q64) Device showing not ready

[bpolito8]

Hi there!

I am trying to set up external flash (w25q64) with my NRF52840 project over SPI. I have adapted the spi_flash sample in an attempt to set up this device, but I am having some issues that I think are related to the device tree. I can’t get the device to show as ready using device_is_ready(). Have I set something up incorrectly?

I’ve included my setup/wiring, prj.conf, overlay, and main.c. 

NRF Connect SDK/Toolchain 2.5.1

Wiring:

Module Pin	DK Pin
VCC	VCC
GND	GND
CS	P1.12
MOSI/DI	P1.13
MISO/DO	P1.14
SCLK	P1.15

prj.conf

CONFIG_STDOUT_CONSOLE=y
CONFIG_FLASH=y
CONFIG_SPI=y
CONFIG_SPI_NOR=y
CONFIG_SPI_NOR_FLASH_LAYOUT_PAGE_SIZE=4096

nrf52840dk_nrf52840.overlay

&spi3_default {
    group1 {
        psels = <NRF_PSEL(SPIM_SCK, 1, 15)>,  /* P1.15, D13 */
                <NRF_PSEL(SPIM_MISO, 1, 14)>, /* P1.14, D12 */
                <NRF_PSEL(SPIM_MOSI, 1, 13)>; /* P1.13, D11 */
    };
};

&spi3_sleep {
    group1 {
        psels = <NRF_PSEL(SPIM_SCK, 1, 15)>,  /* P1.15, D13 */
                <NRF_PSEL(SPIM_MISO, 1, 14)>, /* P1.14, D12 */
                <NRF_PSEL(SPIM_MOSI, 1, 13)>; /* P1.13, D11 */
        low-power-enable;
    };
};


&spi3 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	pinctrl-0 = <&spi3_default>;
	pinctrl-1 = <&spi3_sleep>;
	pinctrl-names = "default", "sleep";
	cs-gpios = <&gpio1 12 GPIO_ACTIVE_LOW>; /* P1.12, D10 */
    w25q64: w25q64@0 {
        compatible = "jedec,spi-nor";
        reg = <0>;
        spi-max-frequency = <1000000>; 
        jedec-id = [ef 40 17];
        size = <DT_SIZE_M(8)>;
    };
};

&nrf_radio_fem_spi {
    status = "disabled";
};

main.c

/*
 * Copyright (c) 2016 Intel Corporation.
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr/kernel.h>
#include <zephyr/drivers/flash.h>
#include <zephyr/drivers/spi.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/device.h>
#include <zephyr/devicetree.h>
#include <stdio.h>
#include <string.h>

#define SPI_FLASH_TEST_REGION_OFFSET 0xff000
#define SPI_FLASH_SECTOR_SIZE        4096

void single_sector_test(const struct device *flash_dev)
{
	const uint8_t expected[] = { 0x55, 0xaa, 0x66, 0x99 };
	const size_t len = sizeof(expected);
	uint8_t buf[sizeof(expected)];
	int rc;

	printf("\nPerform test on single sector");
	/* Write protection needs to be disabled before each write or
	 * erase, since the flash component turns on write protection
	 * automatically after completion of write and erase
	 * operations.
	 */
	printf("\nTest 1: Flash erase\n");

	/* Full flash erase if SPI_FLASH_TEST_REGION_OFFSET = 0 and
	 * SPI_FLASH_SECTOR_SIZE = flash size
	 */
	rc = flash_erase(flash_dev, SPI_FLASH_TEST_REGION_OFFSET,
			 SPI_FLASH_SECTOR_SIZE);
	if (rc != 0) {
		printf("Flash erase failed! %d\n", rc);
	} else {
		printf("Flash erase succeeded!\n");
	}

	printf("\nTest 2: Flash write\n");

	printf("Attempting to write %zu bytes\n", len);
	rc = flash_write(flash_dev, SPI_FLASH_TEST_REGION_OFFSET, expected, len);
	if (rc != 0) {
		printf("Flash write failed! %d\n", rc);
		return;
	}

	memset(buf, 0, len);
	rc = flash_read(flash_dev, SPI_FLASH_TEST_REGION_OFFSET, buf, len);
	if (rc != 0) {
		printf("Flash read failed! %d\n", rc);
		return;
	}

	if (memcmp(expected, buf, len) == 0) {
		printf("Data read matches data written. Good!!\n");
	} else {
		const uint8_t *wp = expected;
		const uint8_t *rp = buf;
		const uint8_t *rpe = rp + len;

		printf("Data read does not match data written!!\n");
		while (rp < rpe) {
			printf("%08x wrote %02x read %02x %s\n",
			       (uint32_t)(SPI_FLASH_TEST_REGION_OFFSET + (rp - buf)),
			       *wp, *rp, (*rp == *wp) ? "match" : "MISMATCH");
			++rp;
			++wp;
		}
	}
}

int main(void)
{
	const struct device *flash_dev = DEVICE_DT_GET(DT_NODELABEL(w25q64));
	
	for(int i = 0; i < 10; i++) {
		if (!device_is_ready(flash_dev)) {
			printk("Attempt %u: %s: device not ready.\n", i + 1, flash_dev->name);
		}
		k_sleep(K_SECONDS(1));
	}

	if (!device_is_ready(flash_dev)) {
		printk("Ending, %s: device not ready.\n", flash_dev->name);
		return 0;
	}

	printf("\n%s SPI flash testing\n", flash_dev->name);
	printf("==========================\n");

	single_sector_test(flash_dev);
	return 0;
}

[Amanda Hsieh]

Hi, 

You can refer to https://github.com/nrfconnect/sdk-zephyr/blob/main/samples/drivers/jesd216/boards/nrf52840dk_nrf52840_spi.overlay for the overlay to test with the unmodified the spi_flash sample. 

Regards,
Amanda H.

[bpolito8]

Hi, thank you for the response!

I've tried this overlay with both the jesd16 and spi_flash samples, no luck with either. In both cases I edited the overlay slightly to have the matching jedec-id and size as the w25q64 flash. I've also made sure to include this overlay and the relevant .conf file in the build configurations for both projects. I made no changes to main.c in the jesd16 sample.

In spi_flash I also named the device `spi_flash0` commented out the `/delete-node/ &mx25r64;` line from the overlay, and used DT_NODELABEL instead of DT_ALIAS when getting the device from devicetree in main.c. I've also moved the flash pins to match the pins for spi2.

jesd216 overlay:

main.c for spi_flash:

Module Pin	DK Pin
VCC	VCC
GND	GND
CS	P0.17
MOSI/DI	P0.20
MISO/DO	P0.21
SCLK	P0.19

spi_flash output:

jesd216 output:

Is there anything else I could be missing?

[Amanda Hsieh]

bpolito8 said:

In spi_flash I also named the device `spi_flash0` commented out the `/delete-node/ &mx25r64;` line from the overlay, and used DT_NODELABEL instead of DT_ALIAS when getting the device from devicetree in main.c.

If you use DT_NODELABEL , the code should be like this

const struct device *flash_dev = DEVICE_DT_GET(DT_NODELABEL(mx25r64)); // if you don't rename for mx25q64

You can refer to https://github.com/nrfconnect/sdk-zephyr/blob/ncs-v3.1.1/samples/drivers/spi_flash/boards/blackpill_f411ce.overlay#L21-L30 for the w25q64. 

[bpolito8]

Apologies for making things unnecessarily confusing, as mentioned in that quoted section I renamed the device in the overlay to `spi_flash0` in the spi_flash sample. In both samples I've made sure the DEVICE_DT_GET(DT_NODELABEL()) call matches the name of the device from the overlay, as they will not build if there is a mismatch.

[Amanda Hsieh]

Got it.

Amanda Hsieh said:

You can refer to https://github.com/nrfconnect/sdk-zephyr/blob/ncs-v3.1.1/samples/drivers/spi_flash/boards/blackpill_f411ce.overlay#L21-L30 for the w25q64. 

Do you update the overlay for the w25q64?