[PATCH v6 1/2] mtd: hisilicon: add a new NAND controller driver for hisilicon hip04 Soc

On 2015/1/13 12:02, Brian Norris wrote:

One more thing:

On Mon, Jan 12, 2015 at 03:28:53PM +0800, Zhou Wang wrote:

quoted

diff --git a/drivers/mtd/nand/hisi504_nand.c b/drivers/mtd/nand/hisi504_nand.c
new file mode 100644
index 0000000..2000f21
--- /dev/null
+++ b/drivers/mtd/nand/hisi504_nand.c

...

quoted

+static int hisi_nand_read_page_hwecc(struct mtd_info *mtd,
+	struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
+{
+	struct hinfc_host *host = chip->priv;
+	int max_bitflips = 0, stat = 0, stat_max, status_ecc;

    drivers/mtd/nand/hisi504_nand.c:547:34: warning: ?stat_max? may be used uninitialized in this function [-Wmaybe-uninitialized]
      int max_bitflips = 0, stat = 0, stat_max, status_ecc;

In fact, there is no chance to run "default case" there as hisi_nfc_ecc_probe
will check this and print error.
I will initialize stat_max with 0 to eliminate this warning.

                                      ^

quoted

+	int stat_1, stat_2;
+
+	chip->read_buf(mtd, buf, mtd->writesize);
+	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	/* errors which can not be corrected by ECC */
+	if (host->irq_status & HINFC504_INTS_UE) {
+		mtd->ecc_stats.failed++;
+	} else if (host->irq_status & HINFC504_INTS_CE) {
+		/* TODO: need add other ECC modes! */

You may want a 'default' case that sets stat_max to zero, then.

quoted

+		switch (chip->ecc.strength) {
+		case 1:
+			stat = hweight8(hinfc_read(host, HINFC504_ECC_STATUS)>>
+						HINFC504_ECC_1_BIT_SHIFT);
+			stat_max = 1;
+			break;
+		case 16:
+			status_ecc = hinfc_read(host, HINFC504_ECC_STATUS) >>
+					HINFC504_ECC_16_BIT_SHIFT & 0x0fff;
+			stat_2 = status_ecc & 0x3f;
+			stat_1 = status_ecc >> 6 & 0x3f;
+			stat = stat_1 + stat_2;
+			stat_max = max_t(int, stat_1, stat_2);
+		}
+		mtd->ecc_stats.corrected += stat;
+		max_bitflips = max_t(int, max_bitflips, stat_max);
+	}
+	host->irq_status = 0;
+
+	return max_bitflips;
+}

Brian

Thanks for your comment!
Zhou Wang

.