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    SubjectRe: [PATCH v3 1/3] mtd: rawnand: denali_dt: add more clocks based on IP datasheet
    Hi Boris,


    2018-06-18 16:46 GMT+09:00 Boris Brezillon <boris.brezillon@bootlin.com>:
    > On Mon, 18 Jun 2018 09:09:02 +0200
    > Richard Weinberger <richard@nod.at> wrote:
    >
    >> Am Freitag, 15. Juni 2018, 03:18:50 CEST schrieb Masahiro Yamada:
    >> > According to the Denali User's Guide, this IP needs three clocks:
    >> >
    >> > - clk: controller core clock
    >> >
    >> > - clk_x: bus interface clock
    >> >
    >> > - ecc_clk: clock at which ECC circuitry is run
    >> >
    >> > Currently, denali_dt.c requires a single anonymous clock and its
    >> > frequency. However, the driver needs to get the frequency of "clk_x"
    >> > not "clk". This is confusing because people tend to assume the
    >> > anonymous clock means the core clock. In fact, I got a report of
    >> > SOCFPGA breakage because the timing parameters are calculated based
    >> > on a wrong frequency.
    >> >
    >> > Instead of the cheesy implementation, the clocks in the real hardware
    >> > should be represented in the driver and the DT-binding.
    >> >
    >> > However, adding new clocks would break the existing platforms. For the
    >> > backward compatibility, the driver still accepts a single clock just as
    >> > before. If clk_x is missing, clk_x_rate is set to a hardcoded value.
    >> > This is fine for existing DT of Socionext UniPhier, and also fixes the
    >> > issue of Altera (Intel) SOCFPGA because both platforms use 200 MHz for
    >> > the bus interface clock.
    >> >
    >> > Fixes: 1bb88666775e ("mtd: nand: denali: handle timing parameters by setup_data_interface()")
    >> > Cc: linux-stable <stable@vger.kernel.org> #4.14+
    >> > Reported-by: Richard Weinberger <richard@nod.at>
    >> > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
    >>
    >> Reviewed-by: Richard Weinberger <richard@nod.at>
    >
    > Maybe a
    >
    > Tested-by: Richard Weinberger <richard@nod.at>
    >
    > ?
    >
    >> Reported-by: Philipp Rosenberger <p.rosenberger@linutronix.de>
    >
    > Should I replace your Reported-by by this one or simply add it?


    I think it is good to have Reported-by
    both from Philipp and Richard.


    Thanks.



    --
    Best Regards
    Masahiro Yamada

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