From nobody Sun Feb 8 13:11:00 2026 Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D433E2FFDF3 for ; Thu, 11 Dec 2025 10:19:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765448380; cv=none; b=Z4RkoBpYU73Ndhi1VAPxWF0A7nBVQG+ZcFKLT5+h/rkUXoGKITm3GrwQoga/1f7kHK4a7AiQxFSErkAB0msEZOFLQtQtw1Oel375VtqNDih3+2WiO5H4wvBLpsxvdzbZlkWjItYrUTO9c60Mp99vLutV+0pOKSXVe1tYoykRz+I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765448380; c=relaxed/simple; bh=2De4h1EvQ9PAGUZJo8VyzNdU/n79s+aks2CEPDXhKMA=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=BzLB+0okdkvjf3JxGitMWpKSfS4ydeF9spcCy7dKKHMd6qpxNa4TPS1xIG6myw3DpipATpT/yE1Od4ufem/eUpj8eNLL6Sitm0HfcTxJj4z02LUqoUfqLIlxR2y9aGb2Z6VLh52/Cx40Qs9oKNwONA13FL40dntmh3xnJt8k0wU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=p2JsjMNs; arc=none smtp.client-ip=209.85.215.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="p2JsjMNs" Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-b99d6bd6cc9so1704004a12.1 for ; Thu, 11 Dec 2025 02:19:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1765448376; x=1766053176; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=c+jHhxdvBq8eCZT3ysFIAELCk1258bcdcN+/mojgVUE=; b=p2JsjMNs0Q8Lo4CEGdsJ8815717Jbax7i5zdCKFMBSvDTUT3XXoRuwXTZlntAe+qy3 DAcOxCaHNiX6+QvRi+vjKMozYCfkuxA5o8JeHhdriz7PE5OqQDHrqOR9rqh+j+B7q8mF hQGbIrnblvwIFLTVelYPehsrJhqIEmaXg7sqQfY2yBjyZs/owm07JPnHdmSp+6+Q5PlR AenV9EC21iQdtqbLqFAjjFyjekJ1twF2D1gsv73srlahVylIfNGEJQDo6KQX0SCSdkXR DBtFw2YKJdyEbLNReow8/dTLwjuVHYMZ1qnfuKvL5Scin32oFp5APv/IKmqvNQuRjp80 lbzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1765448376; x=1766053176; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=c+jHhxdvBq8eCZT3ysFIAELCk1258bcdcN+/mojgVUE=; b=JNN9UgvN6fch4aMLOLI7tsfW86MMSWxXXFZo1Tzxrh6+RmjR4P6QbEid24I7jDYpxC SZ8ClacBJZP+UVMDLVq8P7aQlY3jzAc+SNyw60LWHnhpnPsg8gjOie1ZlKmketa28cB6 wAaHOGmygklO3IH1ykLYtVFbWrSJUkewOSKImPb6YLzd25rLGiUqYl4JF/ioDU3mOm94 A5FHq8O1mdjEDljjE+TS5hDoWgPzPWBrppjDmMe/gWH+VzChC2dRs0XR/RDVB3EYU3Wf o9I0sDD2lXKV3QNI2BnL6aYka8OhjFbAcuUaVNmOp9mXso1AG5YpIz1QovBwLdYQV0ZX f10A== X-Forwarded-Encrypted: i=1; AJvYcCWOPDzed8AqxSng91Atf1Wkbgt58X1EqkXGeF+aeZ33W5CA0abv7NEt/sjP4+lBNb2lRvkEqiXJmtyZy8c=@vger.kernel.org X-Gm-Message-State: AOJu0YxCwo+3PDQ3cYAy/m5/CdEQ6pvklQHbt/SqhPhqS69rxycd37wd tvstwYSiiNZH0WfSFt5lYsHwqXrxgSNcVNMRBVt4BDOC883SxcpGn0aWCajB57tPPdWWXVjoyoL mbtKoJnYVGgspAolY/k3CnoeyhQ== X-Google-Smtp-Source: AGHT+IFiswqXvWXe8hZfJsXbQvgoiKk1nQLxrSGrBb4XVpZ93PMZSPnSs98Cf6Nfhq+HUwPEj/jEXs15x1wpEidaPA== X-Received: from dysb44.prod.google.com ([2002:a05:7300:8b2c:b0:2a4:536d:bffb]) (user=almasrymina job=prod-delivery.src-stubby-dispatcher) by 2002:a05:693c:608a:b0:2ab:f56e:bea6 with SMTP id 5a478bee46e88-2ac055a0933mr4821559eec.39.1765448376075; Thu, 11 Dec 2025 02:19:36 -0800 (PST) Date: Thu, 11 Dec 2025 10:19:29 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.52.0.223.gf5cc29aaa4-goog Message-ID: <20251211101931.2788437-1-almasrymina@google.com> Subject: [PATCH net v1] idpf: read lower clock bits inside the time sandwich From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Mina Almasry , Tony Nguyen , Przemek Kitszel , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Richard Cochran , lrizzo@google.com, namangulati@google.com, willemb@google.com, intel-wired-lan@lists.osuosl.org, milena.olech@intel.com, jacob.e.keller@intel.com, Shachar Raindel Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" PCIe reads need to be done inside the time sandwich because PCIe writes may get buffered in the PCIe fabric and posted to the device after the _postts completes. Doing the PCIe read inside the time sandwich guarantees that the write gets flushed before the _postts timestamp is taken. Cc: lrizzo@google.com Cc: namangulati@google.com Cc: willemb@google.com Cc: intel-wired-lan@lists.osuosl.org Cc: milena.olech@intel.com Cc: jacob.e.keller@intel.com Fixes: 5cb8805d2366 ("idpf: negotiate PTP capabilities and get PTP clock") Suggested-by: Shachar Raindel Signed-off-by: Mina Almasry Reviewed-by: Aleksandr Loktionov Reviewed-by: Jacob Keller Tested-by: Samuel Salin --- drivers/net/ethernet/intel/idpf/idpf_ptp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/idpf/idpf_ptp.c b/drivers/net/ether= net/intel/idpf/idpf_ptp.c index 3e1052d070cf..0a8b50350b86 100644 --- a/drivers/net/ethernet/intel/idpf/idpf_ptp.c +++ b/drivers/net/ethernet/intel/idpf/idpf_ptp.c @@ -108,11 +108,11 @@ static u64 idpf_ptp_read_src_clk_reg_direct(struct id= pf_adapter *adapter, ptp_read_system_prets(sts); =20 idpf_ptp_enable_shtime(adapter); + lo =3D readl(ptp->dev_clk_regs.dev_clk_ns_l); =20 /* Read the system timestamp post PHC read */ ptp_read_system_postts(sts); =20 - lo =3D readl(ptp->dev_clk_regs.dev_clk_ns_l); hi =3D readl(ptp->dev_clk_regs.dev_clk_ns_h); =20 spin_unlock(&ptp->read_dev_clk_lock); base-commit: 885bebac9909994050bbbeed0829c727e42bd1b7 --=20 2.52.0.223.gf5cc29aaa4-goog