Dear Haavard,
in message 20080104154223.1b874a41@dhcp-252-066.norway.atmel.com you wrote:
Wolfgang just noticed that we (you in your original patches and myself in the latest patch) use flash_read8() (etc.) to read from source location too. Since this source is normally not located in FLASH, I'm not so sure anymore if we should use these accessors here too.
Right. I did that just to introduce as few surprises as possible -- originally, the source data was accessed through a volatile pointer, so converting it to use the accessor functions seemed like the natural thing to do.
I don't think it's really necessary though. The source data isn't supposed to change underneath us, so accessing it through a regular, non-volatile pointer should work just fine.
I'm biased - flash_read*() might, for example, contain bank switching code on processors (like MPC5200) which have limitations on the flash sizes thay can directly address. So for copying from flash to flash it might actually be a good idea to use flash_read*(). But then flash_read*() must also work when accessing RAM or PCI memory or ...
I think we should at least document the requirements for flash_read*() - i. e. that it must be capable of reading *arbitrary* memory areas, not only flash memory.
Best regards,
Wolfgang Denk