[U-Boot] [PATCH] nand: mxs_nand_spl: support use of env in SPL

[Scott Wood <scottwood@freescale.com>]

On Fri, 2015-05-08 at 14:39 -0700, Tim Harvey wrote:
> -int nand_spl_load_image(uint32_t offs, unsigned int size, void *buf)
> +int mtd_read(struct mtd_info *mtd, loff_t offs, size_t size, size_t *retlen,
> +	     uchar *buf)
>  {
>  	struct nand_chip *chip;
>  	unsigned int page;
>  	unsigned int nand_page_per_block;
>  	unsigned int sz = 0;
> +	nand_info_t *info = &nand_info[0];

Any reason not to use the passed-in mtd pointer (and fix the
nand_spl_load_image wrapper to pass in &nand_info[0])?

> +/* setup mtd and nand structs and init mxs_nand driver */
> +static int mxs_nand_init(void)
> +{
> +	nand_info_t *info = &nand_info[0];
> +
> +	/* return if already initalized */
> +	if (nand_chip.numchips)
> +		return 0;
> +
> +	/* init mxs nand driver */
> +	board_nand_init(&nand_chip);
> +	info->priv = &nand_chip;
> +	/* set mtd functions */
> +	nand_chip.cmdfunc = mxs_nand_command;
> +	nand_chip.numchips = 1;
> +
> +	/* identify flash device */
> +	puts("NAND : ");
> +	if (mxs_flash_ident(info)) {
> +		printf("Failed to identify\n");
> +		return -1;
> +	}
> +
> +	/* allocate and initialize buffers */
> +	nand_chip.buffers = memalign(ARCH_DMA_MINALIGN,
> +				     sizeof(*nand_chip.buffers));
> +	nand_chip.oob_poi = nand_chip.buffers->databuf + info->writesize;
> +	/* setup flash layout (does not scan as we override that) */
> +	info->size = nand_chip.chipsize;
> +	nand_chip.scan_bbt(info);
> +
> +	printf("%llu MiB\n", (info->size / (1024 * 1024)));
> +	return 0;
> +}

Why did this function need to be moved?

> +int nand_spl_load_image(uint32_t offs, unsigned int size, void *buf)
> +{
> +	return mtd_read(NULL, offs, size, NULL, buf);
> +}

It'd be nice to keep the wrapper near the function it wraps.

I don't see any other such wrappers; is there no other driver that
currently works with SPL env?

>  int nand_default_bbt(struct mtd_info *mtd)
>  {
>  	return 0;
> @@ -223,6 +232,7 @@ int nand_default_bbt(struct mtd_info *mtd)
>  
>  void nand_init(void)
>  {
> +	mxs_nand_init();
>  }

Do you still need the "return if already initialized" check with this
change?  How is this change related to the rest?

-Scott