[PATCH v5 2/2] mtd: rawnand: meson: add support for Amlogic NAND flash controller

On Fri, 19 Oct 2018 15:29:05 +0800
Liang Yang [off-list ref] wrote:

quoted

How about defining that the HW returns an array of __le64 instead and then
define the following macros which you can use after converting in the
CPU endianness

#define ECC_GET_PROTECTED_OOB_BYTE(x, y)	(((x) >> (8 * (1 + y)) & GENMASK(7, 0))
#define ECC_COMPLETE			BIT(31)
#define ECC_ERR_CNT(x)			(((x) >> 24) & GENMASK(5, 0))

(I'm not entirely sure the field positions are correct, but I'll let you
check that).
  

ok. i think it should be:

#define ECC_GET_PROTECTED_OOB_BYTE(x, y)	(((x) >> (8 * y) &
GENMASK(7, 0))

if x represents the u64 and y represents the index of the u64.

Absolutely.

quoted

quoted

+
+#define PER_INFO_BYTE	(sizeof(struct meson_nfc_info_format))
+
+struct meson_nfc_nand_chip {
+	struct list_head node;
+	struct nand_chip nand;
+	bool is_scramble;  

I think I already mentioned the NAND_NEED_SCRAMBLING flag []. Please
drop this field and test (chip->flags & NAND_NEED_SCRAMBLING) instead.
  

em, i use NAND_NEED_SCRAMBLING and is_scramble is set:
static int meson_nand_attach_chip(struct nand_chip *nand)
{
	......
	meson_chip->is_scramble =
		(nand->options & NAND_NEED_SCRAMBLING) ? 1 : 0;
	......
}

Why do you need to add a new field then? Just test
nand->options & NAND_NEED_SCRAMBLING directly or provide a helper
function that does that.