[PATCH 38/39] mtd: nand: denali: remove Toshiba, Hynix specific fixup code

From: Masahiro Yamada
Date: Sat Nov 26 2016 - 13:14:26 EST


The Denali IP can automatically detect device parameters such as
page size, device width, etc. and this driver currently relies on it.
However, this hardware function is problematic.

[1] Due to a hardware bug, various misdetected cases are known.
That is why get_toshiba_nand_para(), get_hynix_nand_para() exist
to fix the misdetected parameters. It is not realistic to add a
new NAND device to the *black list* every time we are hit by a
misdetected case. We would never be able to guarantee that all
the cases are covered.

[2] Because this feature is unreliable, it is disabled on some
platforms.

The nand_scan_ident() sets device parameters such as mtd->writesize,
mtd->erasesize, etc. in a more tested way. We should not set the
hardware registers in a different, unreliable way. Instead, set
the parameters from nand_scan_ident() back to the registers.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

drivers/mtd/nand/denali.c | 39 ++++++---------------------------------
1 file changed, 6 insertions(+), 33 deletions(-)

diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c
index df174ca..1aa19ec 100644
--- a/drivers/mtd/nand/denali.c
+++ b/drivers/mtd/nand/denali.c
@@ -338,35 +338,6 @@ static void get_samsung_nand_para(struct denali_nand_info *denali, u8 device_id)
}
}

-static void get_toshiba_nand_para(struct denali_nand_info *denali)
-{
- /*
- * Workaround to fix a controller bug which reports a wrong
- * spare area size for some kind of Toshiba NAND device
- */
- if ((ioread32(denali->flash_reg + DEVICE_MAIN_AREA_SIZE) == 4096) &&
- (ioread32(denali->flash_reg + DEVICE_SPARE_AREA_SIZE) == 64))
- iowrite32(216, denali->flash_reg + DEVICE_SPARE_AREA_SIZE);
-}
-
-static void get_hynix_nand_para(struct denali_nand_info *denali, u8 device_id)
-{
- switch (device_id) {
- case 0xD5: /* Hynix H27UAG8T2A, H27UBG8U5A or H27UCG8VFA */
- case 0xD7: /* Hynix H27UDG8VEM, H27UCG8UDM or H27UCG8V5A */
- iowrite32(128, denali->flash_reg + PAGES_PER_BLOCK);
- iowrite32(4096, denali->flash_reg + DEVICE_MAIN_AREA_SIZE);
- iowrite32(224, denali->flash_reg + DEVICE_SPARE_AREA_SIZE);
- iowrite32(0, denali->flash_reg + DEVICE_WIDTH);
- break;
- default:
- dev_warn(denali->dev,
- "Unknown Hynix NAND (Device ID: 0x%x).\n"
- "Will use default parameter values instead.\n",
- device_id);
- }
-}
-
/*
* determines how many NAND chips are connected to the controller. Note for
* Intel CE4100 devices we don't support more than one device.
@@ -468,10 +439,6 @@ static u16 denali_nand_timing_set(struct denali_nand_info *denali)
return FAIL;
} else if (maf_id == 0xEC) { /* Samsung NAND */
get_samsung_nand_para(denali, device_id);
- } else if (maf_id == 0x98) { /* Toshiba NAND */
- get_toshiba_nand_para(denali);
- } else if (maf_id == 0xAD) { /* Hynix NAND */
- get_hynix_nand_para(denali, device_id);
}

dev_info(denali->dev,
@@ -1661,6 +1628,12 @@ int denali_init(struct denali_nand_info *denali)
chip->ecc.strength);

iowrite32(chip->ecc.strength, denali->flash_reg + ECC_CORRECTION);
+ iowrite32(mtd->erasesize / mtd->writesize,
+ denali->flash_reg + PAGES_PER_BLOCK);
+ iowrite32(denali->nand.options & NAND_BUSWIDTH_16 ? 1 : 0,
+ denali->flash_reg + DEVICE_WIDTH);
+ iowrite32(mtd->writesize, denali->flash_reg + DEVICE_MAIN_AREA_SIZE);
+ iowrite32(mtd->oobsize, denali->flash_reg + DEVICE_SPARE_AREA_SIZE);

mtd_set_ooblayout(mtd, &denali_ooblayout_ops);

--
2.7.4