[PATCHv2 3/3] mtd: onenand: implement cache program feature for 4kb page onenand

[Kyungmin Park]

Acked-by: Kyungmin Park <kyungmin.park at samsung.com>

On Wed, Nov 3, 2010 at 7:55 PM, Roman Tereshonkov
<roman.tereshonkov at nokia.com> wrote:
> Implement cache program feature for 4KB page onenand.
> This feature improves the write data performance.
> The observed 128KB data program speed change is
> from 8827KB/s to 14156 KB/s when the feature is enabled.
>
> Signed-off-by: Roman Tereshonkov <roman.tereshonkov at nokia.com>
> ---
>  drivers/mtd/onenand/onenand_base.c |   22 +++++++++++++++++++---
>  1 files changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
> index 6b3a875..4d6e6c5 100644
> --- a/drivers/mtd/onenand/onenand_base.c
> +++ b/drivers/mtd/onenand/onenand_base.c
> @@ -1845,7 +1845,7 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
>        const u_char *buf = ops->datbuf;
>        const u_char *oob = ops->oobbuf;
>        u_char *oobbuf;
> -       int ret = 0;
> +       int ret = 0, cmd;
>
>        DEBUG(MTD_DEBUG_LEVEL3, "%s: to = 0x%08x, len = %i\n",
>                __func__, (unsigned int) to, (int) len);
> @@ -1954,7 +1954,19 @@ static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
>                        ONENAND_SET_NEXT_BUFFERRAM(this);
>                }
>
> -               this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
> +               this->ongoing = 0;
> +               cmd = ONENAND_CMD_PROG;
> +
> +               /* Exclude 1st OTP and OTP blocks for cache program feature */
> +               if (ONENAND_IS_CACHE_PROGRAM(this) &&
> +                   likely(onenand_block(this, to) != 0) &&
> +                   ONENAND_IS_4KB_PAGE(this) &&
> +                   ((written + thislen) < len)) {
> +                       cmd = ONENAND_CMD_2X_CACHE_PROG;
> +                       this->ongoing = 1;
> +               }
> +
> +               this->command(mtd, cmd, to, mtd->writesize);
>
>                /*
>                 * 2 PLANE, MLC, and Flex-OneNAND wait here
> @@ -3377,8 +3389,10 @@ static void onenand_check_features(struct mtd_info *mtd)
>        case ONENAND_DEVICE_DENSITY_4Gb:
>                if (ONENAND_IS_DDP(this))
>                        this->options |= ONENAND_HAS_2PLANE;
> -               else if (numbufs == 1)
> +               else if (numbufs == 1) {
>                        this->options |= ONENAND_HAS_4KB_PAGE;
> +                       this->options |= ONENAND_HAS_CACHE_PROGRAM;
> +               }
>
>        case ONENAND_DEVICE_DENSITY_2Gb:
>                /* 2Gb DDP does not have 2 plane */
> @@ -3415,6 +3429,8 @@ static void onenand_check_features(struct mtd_info *mtd)
>                printk(KERN_DEBUG "Chip has 2 plane\n");
>        if (this->options & ONENAND_HAS_4KB_PAGE)
>                printk(KERN_DEBUG "Chip has 4KiB pagesize\n");
> +       if (this->options & ONENAND_HAS_CACHE_PROGRAM)
> +               printk(KERN_DEBUG "Chip has cache program feature\n");
>  }
>
>  /**
> --
> 1.7.0.4
>
>
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