[U-Boot] [PATCH] OneNAND: Fix compiler warnings and add weak attribute to memcpy_16()

[Stefan Roese <sr@denx.de>]

On Friday 07 November 2008, Scott Wood wrote:
> Stefan Roese wrote:
> > This patch adds memcpy_16_from_onenand() and memcpy_16_to_onenand()
> > functions and defaults them to the already available memcpy_16()
> > function. They are defined weak so that they can be overwritten by
> > a board/platform specific version.
> >
> > This is needed for the vcth board support (still to come) which needs
> > custom access routines here.
>
> Can it just override write_bufferram and read_bufferram?

There are multiple functions here using this memcpy_16():

onenand_read_bufferram()
onenand_sync_read_bufferram()
onenand_write_bufferram()

So it seemed "easier" for me to just override the memcpy_16() function itself.

> What does it 
> need to do specially?

On our board the bufferram can't be accessed memory-mapped via pointer access. 
We need special accessor functions. Something like this:

/*
 * Accessor functions replacing the "weak" functions in
 * drivers/mtd/onenand/onenand_base.c
 */
void *memcpy_16_from_onenand(void *dst, const void *src, unsigned int len)
{
	void *ret = dst;
	u16 *d = dst;
	u16 *s = (u16 *)src;

	len >>= 1;
	while (len-- > 0)
		*d++ = ebi_nand_read_word(s++);

	return ret;
}


Best regards,
Stefan

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