Re: [PATCH 1/2] mtd: rawnand: gpmi: Remove explicit default gpmi clock setting for i.MX6

From: Han Xu
Date: Wed Nov 03 2021 - 12:13:25 EST


On 21/11/02 09:20PM, Christian Eggers wrote:
> From: Stefan Riedmueller <s.riedmueller@xxxxxxxxx>
>
> There is no need to explicitly set the default gpmi clock rate during
> boot for the i.MX 6 since this is done during nand_detect anyway.
>
> Signed-off-by: Stefan Riedmueller <s.riedmueller@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> @stable: This patch fixes a bug because this (superfluous) call to
> clk_set_rate() misses the required clock gating. The resulting
> clock glitches can prevent the system from booting.
>
> Changelog:
> -----------
> RFC --> v1
> - Cc: stable@xxxxxxxxxxxxxxx
>
> drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 9 ---------
> 1 file changed, 9 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> index 4d08e4ab5c1b..a1f7000f033e 100644
> --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> @@ -1034,15 +1034,6 @@ static int gpmi_get_clks(struct gpmi_nand_data *this)
> r->clock[i] = clk;
> }
>
> - if (GPMI_IS_MX6(this))
> - /*
> - * Set the default value for the gpmi clock.
> - *
> - * If you want to use the ONFI nand which is in the
> - * Synchronous Mode, you should change the clock as you need.
> - */
> - clk_set_rate(r->clock[0], 22000000);
> -

Acked-by: Han Xu <han.xu@xxxxxxx>

> return 0;
>
> err_clock:
> --
> Christian Eggers
> Embedded software developer
>
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