mtd: rawnand: onfi: Avoid doing a copy of the parameter page

There is no need for copying the parameter page, playing with
pointers does the trick.

There is not functional change.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200428094302.14624-7-miquel.raynal@bootlin.com

diff --git a/drivers/mtd/nand/raw/nand_onfi.c b/drivers/mtd/nand/raw/nand_onfi.c
index 7286c014620bd3e2fcdf7c5e7deeacb53dc0f621..0f3fb9fe4d1db2d26ea54527dc4c149d7743ced9 100644 (file)
--- a/drivers/mtd/nand/raw/nand_onfi.c
+++ b/drivers/mtd/nand/raw/nand_onfi.c
@@ -143,7 +143,7 @@ int nand_onfi_detect(struct nand_chip *chip)
 {
        struct mtd_info *mtd = nand_to_mtd(chip);
        struct nand_memory_organization *memorg;
-       struct nand_onfi_params *p;
+       struct nand_onfi_params *p = NULL, *pbuf;
        struct onfi_params *onfi;
        int onfi_version = 0;
        char id[4];
@@ -158,8 +158,8 @@ int nand_onfi_detect(struct nand_chip *chip)
                return 0;
 
        /* ONFI chip: allocate a buffer to hold its parameter page */
-       p = kzalloc((sizeof(*p) * ONFI_PARAM_PAGES), GFP_KERNEL);
-       if (!p)
+       pbuf = kzalloc((sizeof(*pbuf) * ONFI_PARAM_PAGES), GFP_KERNEL);
+       if (!pbuf)
                return -ENOMEM;
 
        ret = nand_read_param_page_op(chip, 0, NULL, 0);
@@ -169,16 +169,15 @@ int nand_onfi_detect(struct nand_chip *chip)
        }
 
        for (i = 0; i < ONFI_PARAM_PAGES; i++) {
-               ret = nand_read_data_op(chip, &p[i], sizeof(*p), true);
+               ret = nand_read_data_op(chip, &pbuf[i], sizeof(*pbuf), true);
                if (ret) {
                        ret = 0;
                        goto free_onfi_param_page;
                }
 
-               crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&p[i], 254);
-               if (crc == le16_to_cpu(p[i].crc)) {
-                       if (i)
-                               memcpy(p, &p[i], sizeof(*p));
+               crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&pbuf[i], 254);
+               if (crc == le16_to_cpu(pbuf[i].crc)) {
+                       p = &pbuf[i];
                        break;
                }
        }
@@ -188,17 +187,18 @@ int nand_onfi_detect(struct nand_chip *chip)
                unsigned int j;
 
                for (j = 0; j < ONFI_PARAM_PAGES; j++)
-                       srcbufs[j] = p + j;
+                       srcbufs[j] = pbuf + j;
 
                pr_warn("Could not find a valid ONFI parameter page, trying bit-wise majority to recover it\n");
-               nand_bit_wise_majority(srcbufs, ONFI_PARAM_PAGES, p,
-                                      sizeof(*p));
+               nand_bit_wise_majority(srcbufs, ONFI_PARAM_PAGES, pbuf,
+                                      sizeof(*pbuf));
 
-               crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)p, 254);
-               if (crc != le16_to_cpu(p->crc)) {
+               crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)pbuf, 254);
+               if (crc != le16_to_cpu(pbuf->crc)) {
                        pr_err("ONFI parameter recovery failed, aborting\n");
                        goto free_onfi_param_page;
                }
+               p = pbuf;
        }
 
        if (chip->manufacturer.desc && chip->manufacturer.desc->ops &&
@@ -306,14 +306,14 @@ int nand_onfi_detect(struct nand_chip *chip)
        chip->parameters.onfi = onfi;
 
        /* Identification done, free the full ONFI parameter page and exit */
-       kfree(p);
+       kfree(pbuf);
 
        return 1;
 
 free_model:
        kfree(chip->parameters.model);
 free_onfi_param_page:
-       kfree(p);
+       kfree(pbuf);
 
        return ret;
 }