Using NRFX SPIS in nRF Connect SDK

RE: Using NRFX SPIS in nRF Connect SDK

Anthony — Thu, 17 Oct 2024 13:28:26 GMT

Than you very much for you answers.

My bad, I was calling IRQ_CONNECT() outside of any function, thinking it operated at compile time.

The test project with NRFX SPIS works now with the following configuration:

nrf52840dk_nrf52840.overlay :

&spi1 {
    // Keep the compatible property otherwise a compile error ('NRFX_SPIS1_INST_IDX' undeclared here) occurs.
    // https://devzone.nordicsemi.com/f/nordic-q-a/93675/nrfx-spi-migration-from-ncs-1-9-to-ncs-2-0
    // https://github.com/nrfconnect/sdk-zephyr/commit/451a6ed6abbf35262bbcf0f926e7941f6c74c632
    compatible = "nordic,nrf-spis";
    status = "disabled";
};

prj.conf :

CONFIG_NRFX_SPIS1=y

With the C code based on modules/hal/nordic/nrfx/samples/src/nrfx_spim_spis/advanced_non_blocking/main.c.

Regarding Turbo's interrogation, the reason for using (or evaluating the usage of) the nrfx library is to have more flexibility compared to the standard Zephyr way of configuring peripherals (although Zephyr also offers some flexibility: https://github.com/nrfconnect/sdk-zephyr/blob/v3.0.99-ncs1/samples/boards/nrf/dynamic_pinctrl/src/remap.c#L61 ) . For example, we are evaluating the feasibility of detecting the activation of the SPIS CSN pin without linking it physically to another GPIO, enabling/disabling peripherals at runtime, or changing their configuration dynamically, etc.

RE: Using NRFX SPIS in nRF Connect SDK

Håkon Alseth — Wed, 16 Oct 2024 10:25:50 GMT

Hi,

If you want to not initialize the zephyr SPI driver, but only use the nrfx driver, you need to:

1. enable the node in DT

2. disable the zephyr driver component, in this case: CONFIG_SPI=n

Now the subsys will not enable nrfx_spis during boot-up, which is the root-cause of this behavior:

[quote user="Anthony Groccia"]If I remove the IRQ_CONNECT line, the project compiles but nrfx_spis_init() returns NRFX_ERROR_ALREADY.[/quote]

[quote user="Anthony Groccia"]where the IRQ_CONNECT line is as follows :[/quote]

It seems that you are defining SPIM_INST_IDX, and not SPIS_INST_IDX. Could you check if this is the problem?

Kind regards,

Håkon

RE: Using NRFX SPIS in nRF Connect SDK

Turbo J — Wed, 16 Oct 2024 09:53:03 GMT

Any reason why you try to code yourself instead of just using the existing driver in zephyr/drivers/spi/spi_nrfx_spis.c source file? It would get enabled via correct DT automagically.

RE: Using NRFX SPIS in nRF Connect SDK

Anthony — Wed, 16 Oct 2024 09:25:35 GMT

Thank you for you answer.

I tried to set the `status` field of the SPIS1 peripheral to "okay" in the device tree.
When I put the line with IRQ_CONNECT(...), the following compile error occurs:

C:/ncs/v2.7.0/zephyr/include/zephyr/arch/arm/irq.h:117:1: error: expected identifier or '(' before '{' token
  117 | { \
      | ^
C:/ncs/v2.7.0/zephyr/include/zephyr/irq.h:49:9: note: in expansion of macro 'ARCH_IRQ_CONNECT'
   49 |         ARCH_IRQ_CONNECT(irq_p, priority_p, isr_p, isr_param_p, flags_p)

where the IRQ_CONNECT line is as follows :

#define SPIM_INST_IDX 1

IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_SPIS_INST_GET(SPIS_INST_IDX)), IRQ_PRIO_LOWEST, NRFX_SPIS_INST_HANDLER_GET(SPIS_INST_IDX), 0, 0);

If I remove the IRQ_CONNECT line, the project compiles but nrfx_spis_init() returns NRFX_ERROR_ALREADY.

I tried several other combinations. I also tried to define the SPI pin numbers in the device tree, but that didn't solve the problem :

&pinctrl {
    spis_default: spis_default {
        group1 {
            psels = <NRF_PSEL(SPIS_SCK, 1, 04)>,
                <NRF_PSEL(SPIS_MISO, 1, 06)>,
                <NRF_PSEL(SPIS_MOSI, 1, 05)>;
        };
    };
};

This is how the spis1 peripheral appears in the combined device tree in build/zephyr/zephyr.dts :

		spi1: spi@40004000 {
			compatible = "nordic,nrf-spis";
			#address-cells = < 0x1 >;
			#size-cells = < 0x0 >;
			reg = < 0x40004000 0x1000 >;
			interrupts = < 0x4 0x1 >;
			max-frequency = < 0x7a1200 >;
			easydma-maxcnt-bits = < 0x10 >;
			status = "okay";
			pinctrl-0 = < &spis_default >;
			pinctrl-1 = < &spi1_sleep >;
			pinctrl-names = "default", "sleep";
			def-char = < 0xff >;
		};

I also tried to compile the example in modules/hal/nordic/nrfx/samples/src/nrfx_spim_spis/advanced_non_blocking/ using `west build -b nrf52840dk_nrf52840`, but the compilation fails (CMake Error at CMakeLists.txt:11 GET_DEVICE_CONFIG_FILES Macro invoked with incorrect arguments).

Would you have other ideas that I can try ? I can upload the succinct source file of my project if needed.

RE: Using NRFX SPIS in nRF Connect SDK

Turbo J — Tue, 15 Oct 2024 12:16:30 GMT

The status property must be set to "okay". Might fix the IRQ_CONNECT() problem.

Not sure if you needed more changes in the device tree - look at the combined tree files in the build/zephyr directory.