Re: [PATCH] mlxsw: spectrum_ptp: fix 32-bit build

[Sergei Shtylyov]

Hello!

On 19.06.2019 16:31, Arnd Bergmann wrote:

> On 32-bit architectures, we cannot easily device 64-bit numbers:

   s/device/divide/?

> ERROR: "__aeabi_uldivmod" [drivers/net/ethernet/mellanox/mlxsw/mlxsw_spectrum.ko] undefined!
>
> Use do_div() to annotate the fact that we know this is an

   div_u64() really?

> expensive operation.
>
> Fixes: 992aa864dca0 ("mlxsw: spectrum_ptp: Add implementation for physical hardware clock operations")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>   drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c
> index 2a9bbc90225e..618e329e1490 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c
> +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ptp.c
> @@ -87,7 +87,7 @@ mlxsw_sp1_ptp_phc_settime(struct mlxsw_sp_ptp_clock *clock, u64 nsec)
>   	u32 next_sec;
>   	int err;
>   
> -	next_sec = nsec / NSEC_PER_SEC + 1;
> +	next_sec = div_u64(nsec, NSEC_PER_SEC) + 1;
>   	next_sec_in_nsec = next_sec * NSEC_PER_SEC;
>   
>   	spin_lock(&clock->lock);

MBR, Sergei