[PATCH] riscv: sifive: fu740: reduce DDR speed from 1866MT/s to 1600MT/s

[Leo Liang]

On Thu, Feb 22, 2024 at 03:52:03PM +0100, thomas.perrot at bootlin.com wrote:
> From: Thomas Perrot <thomas.perrot at bootlin.com>
> 
> It appears that there is some timing marginality either in the
> board layout or the SoC that results in occasional data corruption
> on some boards.
> We observed this issue on some of the new HiFive Unmatched RevB
> boards during volume production as well as some of the original
> HiFive Unmatched boards from 2021 in our possession. This means
> that there are other boards out there that might have the issue
> too.
> 
> We have done some limited testing with DDR4 at 1600MT/s and
> faulty boards (failing at 1866MT/s) passed.
> We plan further testing after we procure a temperature chamber.
> 
> Signed-off-by: Thomas Perrot <thomas.perrot at bootlin.com>
> ---
>  arch/riscv/dts/fu740-c000-u-boot.dtsi | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Leo Yu-Chi Liang <ycliang at andestech.com>