[U-Boot] [PATCH] [DFU] Implement NAND dfu support

[Scott Wood <scottwood@freescale.com>]

On 12/10/2012 09:24:32 AM, Pantelis Antoniou wrote:
> Introduce on-the fly DFU NAND support.
> 
> Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com>
> ---
>  drivers/dfu/Makefile   |   1 +
>  drivers/dfu/dfu.c      |   7 ++
>  drivers/dfu/dfu_nand.c | 194  
> +++++++++++++++++++++++++++++++++++++++++++++++++
>  include/dfu.h          |  23 ++++++
>  4 files changed, 225 insertions(+)
>  create mode 100644 drivers/dfu/dfu_nand.c

What is DFU?  I don't see anything in README or doc/, despite there  
already being CONFIG symbols for it.

> +static int nand_block_op(enum dfu_nand_op op, struct dfu_entity *dfu,
> +			u64 offset, void *buf, long *len)
> +{
> +	char cmd_buf[DFU_CMD_BUF_SIZE];
> +	u64 start, count;
> +	int ret;
> +	int dev;
> +	loff_t actual;
> +
> +	/* if buf == NULL return total size of the area */
> +	if (buf == NULL) {
> +		*len = dfu->data.nand.size;
> +		return 0;
> +	}
> +
> +	start = dfu->data.nand.start + offset + dfu->bad_skip;
> +	count = *len;
> +	if (start + count >
> +			dfu->data.nand.start + dfu->data.nand.size) {
> +		printf("%s: block_op out of bounds\n", __func__);
> +		return -1;
> +	}
> +	dev = nand_curr_device;
> +	if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE ||
> +		!nand_info[dev].name) {
> +		printf("%s: invalid nand device\n", __func__);
> +		return -1;
> +	}
> +
> +	sprintf(cmd_buf, "nand %s %p %llx %llx",
> +		op == DFU_OP_READ ? "read" : "write",
> +		 buf, start, count);
> +
> +	debug("%s: %s 0x%p\n", __func__, cmd_buf, cmd_buf);
> +	ret = run_command(cmd_buf, 0);

Why not use the C interface to NAND?

> +	/* find out how much actual bytes have been written */
> +	/* the difference is the amount of skip we must add from now on  
> */
> +	actual = nand_extent_skip_bad(&nand_info[dev], start, count);

...especially since you already need to interact with it here?

-Scott