Re: [ECOS] [RFC] CYGHWR_IO_FLASH_DEVICE_NOT_IN_RAM

[Jonathan Larmour <jifl at eCosCentric dot com>]

Jani Monoses wrote:
> Hi
> there are a few flash drivers which still implement the
> CYGHWR_IO_FLASH_DEVICE_NOT_IN_RAM interface while the
> way to handle the problem of executing from/modifying the flash 
> in the same time is solved in newer drivers by putting the
> sensitive functions to sections which at load time are put in RAM
> by appending section attributes to their prototypes.
> Still there might be cases when the functions can stay in flash -
> one that I can think of is when the flash has separately erasable/programmable
> regions and you're sure you'll only touch one while the code is in the other.
> At least one comment in the strataflash .cdl says that:
>
>         Rarely, it is useful to disable the request that flash driver code
>         be copied to separate RAM for execution.  This option lets you do that.
>
> So according to this a replacement of the interface with the new way using attributes
> could have this small regression.
>
> What do the maintainers think?
>
> 1)"I wish people stopped nitpicking the sources and do some real work instead of cleanups"
> 2)"All drivers should use the section attribute"
> 3)"We could have a macro which expands to the current attribute or to nothing if a driver
> independent cdl option is set and all drivers turned to using this macro"
> 4)...

1 and 4 for sure :). To me 3 seems best, but then I haven't the time to 
write a patch for all that, so it's easy for me to say ;).

Note: be careful to avoid breaking things for 3rd party drivers with an 
interface change. Not every flash driver that exists is checked into the 
master repo.

Jifl
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