Re: [RESEND PATCH v2 21/53] mtd: nand: denali: move multi device fixup code to a helper function

From: Boris Brezillon
Date: Mon Mar 27 2017 - 12:13:56 EST


On Thu, 23 Mar 2017 05:07:20 +0900
Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote:

> Collect multi NAND fixups into a helper function instead of
> scattering them in denali_init().
>
> I am rewording the comment block to clearly explain what is called
> "multi device".

I will take the patch (and the next one too), but I might reconsider
supporting this kind of thing (2 x 8bits devices connected on a 16bits
bus) in the core.

>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> ---
>
> Changes in v2:
> - Reword the comment block for clarification
>
> drivers/mtd/nand/denali.c | 54 +++++++++++++++++++++++++++++------------------
> 1 file changed, 33 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c
> index 1706975..4e63d57 100644
> --- a/drivers/mtd/nand/denali.c
> +++ b/drivers/mtd/nand/denali.c
> @@ -1458,6 +1458,36 @@ static void denali_drv_init(struct denali_nand_info *denali)
> denali->irq_status = 0;
> }
>
> +static void denali_multidev_fixup(struct denali_nand_info *denali)
> +{
> + struct nand_chip *chip = &denali->nand;
> + struct mtd_info *mtd = nand_to_mtd(chip);
> +
> + /*
> + * Support for multi device:
> + * When the IP configuration is x16 capable and two x8 chips are
> + * connected in parallel, DEVICES_CONNECTED should be set to 2.
> + * In this case, the core framework knows nothing about this fact,
> + * so we should tell it the _logical_ pagesize and anything necessary.
> + */
> + denali->devnum = ioread32(denali->flash_reg + DEVICES_CONNECTED);
> +
> + mtd->size <<= denali->devnum - 1;
> + mtd->erasesize <<= denali->devnum - 1;
> + mtd->writesize <<= denali->devnum - 1;
> + mtd->oobsize <<= denali->devnum - 1;
> + chip->chipsize <<= denali->devnum - 1;
> + chip->page_shift += denali->devnum - 1;
> + chip->phys_erase_shift += denali->devnum - 1;
> + chip->bbt_erase_shift += denali->devnum - 1;
> + chip->chip_shift += denali->devnum - 1;
> + chip->pagemask <<= denali->devnum - 1;
> + chip->ecc.size *= denali->devnum;
> + chip->ecc.bytes *= denali->devnum;
> + chip->ecc.strength *= denali->devnum;
> + denali->bbtskipbytes *= denali->devnum;
> +}
> +
> int denali_init(struct denali_nand_info *denali)
> {
> struct nand_chip *chip = &denali->nand;
> @@ -1540,24 +1570,6 @@ int denali_init(struct denali_nand_info *denali)
> }
>
> /*
> - * support for multi nand
> - * MTD known nothing about multi nand, so we should tell it
> - * the real pagesize and anything necessery
> - */
> - denali->devnum = ioread32(denali->flash_reg + DEVICES_CONNECTED);
> - chip->chipsize <<= denali->devnum - 1;
> - chip->page_shift += denali->devnum - 1;
> - chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
> - chip->bbt_erase_shift += denali->devnum - 1;
> - chip->phys_erase_shift = chip->bbt_erase_shift;
> - chip->chip_shift += denali->devnum - 1;
> - mtd->writesize <<= denali->devnum - 1;
> - mtd->oobsize <<= denali->devnum - 1;
> - mtd->erasesize <<= denali->devnum - 1;
> - mtd->size = chip->numchips * chip->chipsize;
> - denali->bbtskipbytes *= denali->devnum;
> -
> - /*
> * second stage of the NAND scan
> * this stage requires information regarding ECC and
> * bad block management.
> @@ -1600,11 +1612,9 @@ int denali_init(struct denali_nand_info *denali)
> }
>
> mtd_set_ooblayout(mtd, &denali_ooblayout_ops);
> - chip->ecc.bytes *= denali->devnum;
> - chip->ecc.strength *= denali->devnum;
>
> /* override the default read operations */
> - chip->ecc.size = ECC_SECTOR_SIZE * denali->devnum;
> + chip->ecc.size = ECC_SECTOR_SIZE;
> chip->ecc.read_page = denali_read_page;
> chip->ecc.read_page_raw = denali_read_page_raw;
> chip->ecc.write_page = denali_write_page;
> @@ -1613,6 +1623,8 @@ int denali_init(struct denali_nand_info *denali)
> chip->ecc.write_oob = denali_write_oob;
> chip->erase = denali_erase;
>
> + denali_multidev_fixup(denali);
> +
> ret = nand_scan_tail(mtd);
> if (ret)
> goto failed_req_irq;