From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-170.mta1.migadu.com (out-170.mta1.migadu.com [95.215.58.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 301E4311969 for ; Wed, 29 Oct 2025 20:33:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761770042; cv=none; b=sGm6e8BtzGsqyc5/ZMWqGrZMnONs9+QUrQYcsJskCa+D3P72JHk0rGwNnF9I/BOv1wsQlEjigH1aHCsuLZeuuqiFQFxWv0Svojr0geAjNaxAnjCvhLcKjvPx3v6d8gD5w1RJC8f+/KF9I9GMINBepav7MfzVaxcUlPGDDHHg/Sw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761770042; c=relaxed/simple; bh=f4BgwcQbfSKq6anpK4XuvXsMkFdycBzStXXczZDDPlo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=NLnAUH2Enopx6dsI+SSMt1GdHuHzM04H5+gVoWV8x4ACP5vs2GP831p4lXL88HsgVvPbyzjaN1SpGw0A4Ra5WN5p9lgWtYXcZhF+Cko/0hr5jtolcWodXc7yFlVVZ4nKnxVx8fMMYFkFG7JypDQRh04qzi+3pEgzexUKl4Wm+j8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=eqK8PpQV; arc=none smtp.client-ip=95.215.58.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="eqK8PpQV" Message-ID: <03fa25f0-b7f5-4b3e-8a93-0637d0222719@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1761770038; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2k0g02pMCf4/8FiMhdYemYEY3w1Y1j1mpeO8X6WI3F8=; b=eqK8PpQVhB45TQ+e9goYGAPAg0O2Dp06e6a1Qy0SoalbGt2/CB4bHuWi9DNZmYphHq5OsB CRFgUrQja5ezsp4/USWxeyJSdcFXjFc/PnpUdXp7sr/7dZJ+a5JgQ5iQ3UFdcn1W1qf3MP 7KHJ40xm9nGAtKsecbRfiSgdOH592uw= Date: Wed, 29 Oct 2025 20:33:55 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH net] ptp: Allow exposing cycles only for clocks with free-running counter To: Carolina Jubran , Richard Cochran , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Dragos Tatulea , Tariq Toukan References: <20251029083813.2276997-1-cjubran@nvidia.com> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Vadim Fedorenko In-Reply-To: <20251029083813.2276997-1-cjubran@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 29/10/2025 08:38, Carolina Jubran wrote: > The PTP core falls back to gettimex64 and getcrosststamp when > getcycles64 or getcyclesx64 are not implemented. This causes the CYCLES > ioctls to retrieve PHC real time instead of free-running cycles. > > Reject PTP_SYS_OFFSET_{PRECISE,EXTENDED}_CYCLES for clocks without > free-running counter support since the result would represent PHC real > time and system time rather than cycles and system time. > > Fixes: faf23f54d366 ("ptp: Add ioctl commands to expose raw cycle counter values") > Signed-off-by: Carolina Jubran > Reviewed-by: Dragos Tatulea > Reviewed-by: Tariq Toukan > --- > drivers/ptp/ptp_chardev.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c > index 8106eb617c8c..c61cf9edac48 100644 > --- a/drivers/ptp/ptp_chardev.c > +++ b/drivers/ptp/ptp_chardev.c > @@ -561,10 +561,14 @@ long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd, > return ptp_mask_en_single(pccontext->private_clkdata, argptr); > > case PTP_SYS_OFFSET_PRECISE_CYCLES: > + if (!ptp->has_cycles) > + return -EOPNOTSUPP; > return ptp_sys_offset_precise(ptp, argptr, > ptp->info->getcrosscycles); > > case PTP_SYS_OFFSET_EXTENDED_CYCLES: > + if (!ptp->has_cycles) > + return -EOPNOTSUPP; > return ptp_sys_offset_extended(ptp, argptr, > ptp->info->getcyclesx64); > default: Fair point. Reviewed-by: Vadim Fedorenko