Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

Naeem Maroof — Thu, 08 Aug 2024 14:12:26 GMT

Hi Amit,

I have tested on nrf52840dk, and I do not get any problem

I can see the correct functionality as well.

Just for reference, I am putting the nrf52840DK overlay here which is based on your overlay, the sample output dts, and the information from the DK guide.

/delete-node/ &mx25r64;
&qspi{
    status = "disabled";
    
};
&spi3{
    compatible = "nordic,nrf-spim";
    status = "okay";
    pinctrl-0 = < &spi3_default >;
    pinctrl-1 = < &spi3_sleep >;
    pinctrl-names = "default", "sleep";
    cs-gpios = <&gpio0 17 GPIO_ACTIVE_LOW>; /* D10 */
    mx25r64: mx25r6435f@0 {
        compatible = "jedec,spi-nor";
        reg = < 0x0 >;
        spi-max-frequency = < 8000000 >;
        status = "okay";
        jedec-id = [ C2 28 17 ];
        sfdp-bfp = [ E5 20 F1 FF FF FF FF 03 44 EB 08 6B 08 3B 04 BB EE FF FF FF FF FF 00 FF FF FF 00 FF 0C 20 0F 52 10 D8 00 FF 23 72 F5 00 82 ED 04 CC 44 83 68 44 30 B0 30 B0 F7 C4 D5 5C 00 BE 29 FF F0 D0 FF FF ];
        size = < 0x4000000 >;
        has-dpd;
        t-enter-dpd = < 0x2710 >;
        t-exit-dpd = < 0x88b8 >;
    };
};

&pinctrl{
    spi3_default: spi3_default {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 19)>,
				<NRF_PSEL(SPIM_MISO, 0, 21)>,
				<NRF_PSEL(SPIM_MOSI, 0, 20)>;
		};
	};

	spi3_sleep: spi3_sleep {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 19)>,
				<NRF_PSEL(SPIM_MISO, 0, 21)>,
				<NRF_PSEL(SPIM_MOSI, 0, 20)>;
			low-power-enable;
		};
	};
};

/{
    aliases{
        spi-flash0 = &mx25r64;
    };
};

I am using the exact sample without modifying anything in the main except including a header file for the spi.

In the project configurations, SPI is enabled and QSPI is disabled; similarly in the overlay.

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

AKO — Tue, 06 Aug 2024 05:22:13 GMT

. You can see in the above image when I execute line 242, I am getting exceptions and that could be because of the erase is not pointing to any valid function (as seen in watch)

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

Naeem Maroof — Mon, 05 Aug 2024 15:28:09 GMT

what error you are getting now?

defining aliases for instances is fine.

you can do the debugging to see what is causing the issue.

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

AKO — Wed, 24 Jul 2024 13:22:12 GMT

My Device Tree:

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

AKO — Wed, 24 Jul 2024 13:15:09 GMT

I am using the following to the flash device from DT:

#define SPI_FLASH DEVICE_DT_GET(DT_ALIAS(ext_flash))

The aliases where I have used ext_flash:

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

AKO — Wed, 24 Jul 2024 13:07:27 GMT

There are no compilation error, and I am able to flash it. The example that you have shared worked fine with QSPI (where the Flash_Erase/Flash_Read API are connecting with Zephyr APIs) but I am using SPI-NOR where I am facing issue.

Also, I am able to get the flash device from the Device tree.

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

Naeem Maroof — Wed, 24 Jul 2024 10:41:18 GMT

[quote user="AKO"]I have checked this example but it didn't worked for me[/quote]

What do you mean by "did not work"? Did it not compile well? Were you able to flash it? Did you get runtime error?

[quote user="AKO"]but here I see that no function is assigned to api->erase [/quote]

In the main, you will see that we are getting the flash device from the devicetree by calling DEVICE_DT_GET().

Therefore, the drivers configured for that device in the DTS would be used to connect to the flash api.

I have compiled the example for NRF52840, and I can see (in the DTS) that spi-flash0 is using QSPI-NOR driver from NORDIC (see compatible), and in the NRF_QSPI_NOR.C file we see that:

Hence the flash erase would eventually connect with qspi_nor_erase from this driver.

If you are unfamiliar with this then I would recommend you to go through the DevAcademy courses that would quickly ramp up expertise working with NCS/Zephyr.

Warm regards,

Naeem

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

AKO — Tue, 23 Jul 2024 12:29:51 GMT

I have checked this example but it didn't worked for me. When I was calling the flash_erase I was getting some wierd observation.

This functions calls the following code:

static inline int z_impl_flash_erase(const struct device *dev, off_t offset,

size_t size)

{

const struct flash_driver_api *api =

(const struct flash_driver_api *)dev->api;

int rc;

rc = api->erase(dev, offset, size);

return rc;

}

but here I see that no function is assigned to api->erase

RE: Use of Zephyr inbuilt APIs to Use External Flash with nRF9160

Naeem Maroof — Tue, 23 Jul 2024 09:03:41 GMT

You might want to look at Zephyr Flash sample that demonstrates the use of flash API:

Zephyr Flash Sample