DT_CHOSEN is not working.

[shlomots]

I am trying to work with my flash deivce in my code.
for some reason:

const static struct device *int_flash_dev = DEVICE_DT_GET(DT_CHOSEN(zephyr_flash));

doesnt work, but this does: 

const static struct device *int_flash_dev = DEVICE_DT_GET(DT_MTD_FROM_FIXED_PARTITION(DT_NODELABEL(my_partition)));

where the my_partition node is coming from my overlay file:

&flash0 {

partitions {

/* 0xf0000 to 0xf7fff reserved for TF-M partitions */

my_partition: partition@0 {

label = "my_storage";

reg = <0x0 0x1>;

};

};

};


The error message I am getting is:

undefined reference to `__device_dts_ord_94'
collect2: error: ld returned 1 exit status

the chosen node on my device tree looks like this:

chosen {

zephyr,sram = &sram0;

zephyr,flash = &flash0;

zephyr,code-partition = &slot0_partition;
.
.
.

}


shouldn't both of those evaluate to the same device? 

thanks in advance,
shlomo

[DanielNG]

Hi,
if you take a look at your zephyr.dts in your build folder, you can see that flash0 is actually not a device. It's just a layout/partition node. The actual hardware/device node is flash_controller. This is a common pattern for internal flash across various SoC (for external flash, oftentimes flash0 is the actual device)


So, you can use 

const static struct device *int_flash_dev = DEVICE_DT_GET(DT_PARENT(DT_CHOSEN(zephyr_flash)));

or

const static struct device *int_flash_dev = DEVICE_DT_GET(DT_NODELABEL(flash_controller));

or just keep your 

const static struct device *int_flash_dev = DEVICE_DT_GET(DT_MTD_FROM_FIXED_PARTITION(DT_NODELABEL(my_partition)));

You can also filter for "soc_nv_flash" compatibility as this is for layout/partition

#if DT_NODE_HAS_COMPAT(DT_CHOSEN(zephyr_flash), soc_nv_flash)
#  define FLASH_DEV_NODE DT_PARENT(DT_CHOSEN(zephyr_flash))
#else
#  define FLASH_DEV_NODE DT_CHOSEN(zephyr_flash)
#endif

[shlomots]

Thank you!
this ticket can be closed