Re: [PATCH net-next v2 1/2] drivers: net: stmmac: handle start time set in the past for flexible PPS

[Gatien CHEVALLIER]

On 7/29/25 18:58, Simon Horman wrote:
> On Tue, Jul 29, 2025 at 04:52:00PM +0200, Gatien Chevallier wrote:
> > In case the time arguments used for flexible PPS signal generation are in
> > the past, consider the arguments to be a time offset relative to the MAC
> > system time.
> >
> > This way, past time use case is handled and it avoids the tedious work
> > of passing an absolute time value for the flexible PPS signal generation
> > while not breaking existing scripts that may rely on this behavior.
> >
> > Signed-off-by: Gatien Chevallier <gatien.chevallier@xxxxxxxxxxx>
> > ---
> >   drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c | 31 ++++++++++++++++++++++++
> >   1 file changed, 31 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
> > index 3767ba495e78d210b0529ee1754e5331f2dd0a47..5c712b33851081b5ae1dbf2a0988919ae647a9e2 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
> > @@ -10,6 +10,8 @@
> >   #include "stmmac.h"
> >   #include "stmmac_ptp.h"
> >   
> > +#define PTP_SAFE_TIME_OFFSET_NS	500000
> > +
> >   /**
> >    * stmmac_adjust_freq
> >    *
> > @@ -172,6 +174,10 @@ static int stmmac_enable(struct ptp_clock_info *ptp,
> >   
> >   	switch (rq->type) {
> >   	case PTP_CLK_REQ_PEROUT:
> > +		struct timespec64 curr_time;
> > +		u64 target_ns = 0;
> > +		u64 ns = 0;
> > +
>
> I think you need to wrap this case in {}, as is already done for the following
> case.
>
> Clang 20.1.8 W=1 build warn about the current arrangement as follows.
>
>    .../stmmac_ptp.c:177:3: warning: label followed by a declaration is a C23 extension [-Wc23-extensions]
>      177 |                 struct timespec64 curr_time;
>          |                 ^
>    1 warning generated.
>
> GCC 8.5.0 (but not 15.1.0) also flags this problem.

Hello Simon,

Ok I will comply for V3.

> Also, please note:
>
> ## Form letter - net-next-closed
>
> The merge window for v6.17 has begun and therefore net-next is closed
> for new drivers, features, code refactoring and optimizations. We are
> currently accepting bug fixes only.
>
> Please repost when net-next reopens after 11th August.
>
> RFC patches sent for review only are obviously welcome at any time.
>
> See: https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#development-cycle

Thank you for pointing this out.

Best regards,
Gatien