Fixed the flash writing bug on RP2040 caused by flash_cs_force

[TerryGeng]

In #11, a portion of code was stripped from flash_rpi_pico.c from Zephyr's code base and was inserted here and was revised to be compatible with RP2350. Notably, the type of the argument was changed from enum into bool, resulting in compatiblity issue with existing RP2040 code that calls this function with an enum.

Fixes zephyrproject-rtos/zephyr#95729
Fixes zephyrproject-rtos/zephyr#96224

[TerryGeng]

@soburi @ajf58 @ThreeEights @yonsch @kartben

Would you please have a look if you have a chance?

[ajf58]

Thanks for raising this. It looks like @hanan619 can't be @ mentioned. I've started to look at this, but need to spend a bit of time revisiting the original pair of PRs.

[TerryGeng]

This might be an irrelevant point: As I'm taking a closer look at #11, it states that the added code is mostly from the bootrom, and I think it can be directly called from the bootrom if the correct offset is known. Some functions don't exist in the bootrom lookup table (those added by #11) but can be looked up from the bootrom ELF file.

For RP2040 bootrom B2:

> objdump -t b2.elf | less

00000bb8 l     F .text  00000024 flash_put_cmd_addr
...
00001824 l     F .text  0000003c flash_wait_ready
...
00001770 l     F .text  00000068 flash_put_get
...
00001804 l     F .text  0000001e flash_enable_write

So maybe there isn't a need to copy that code at all? 👀

[TerryGeng]

@ajf58 @soburi Nudge... Did you get a chance to look into this?

[soburi]

LGTM. Thank you for your fix!