From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 270EBC6FA8E for ; Sun, 26 Feb 2023 14:49:34 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id AC70F40566; Sun, 26 Feb 2023 14:49:33 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org AC70F40566 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osuosl.org; s=default; t=1677422973; bh=9CqwI1e6CRhPeMy2/Aw5U4cGtDncADlwATMBH2eXHhg=; h=From:To:Date:In-Reply-To:References:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: Cc:From; b=Bp7h0so5gD71pnlijuPPy+siuFJtGSYsW2XMJS/XZyfqj1Gl6CTdKS09Rm5DszQW2 BdATNzS+qi/fswlCE/9zl/TVYMuyQgrmhHMbvIfgoETUK6lWFcMdHrIxEQIIye7S0y KfqIcpipwh9HWaMDLB+kPXOJkJUEkNRAhfdsoWJ/GS9dDfbOZWhWnj6eLkAv6+3Fis L4TDbjRF9tbF6klHgedyBVHMLZ+Kj+s07PQMkU16qGXLn18P4E/erc/VliCru4U92D VZEG2ocXLM5yjrXNN/l+uPPlzrfB49wunbYCpjFcNtYCYlvli+OY60Gs1eA5g9w7pi O6Mhdy28arXEg== X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xLZRacIBoxSO; Sun, 26 Feb 2023 14:49:32 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by smtp2.osuosl.org (Postfix) with ESMTP id 9C739405AB; Sun, 26 Feb 2023 14:49:32 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 9C739405AB Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by ash.osuosl.org (Postfix) with ESMTP id 139531BF868 for ; Sun, 26 Feb 2023 14:49:27 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id E1E5B81372 for ; Sun, 26 Feb 2023 14:49:26 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org E1E5B81372 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 438pTF6PZkEC for ; Sun, 26 Feb 2023 14:49:26 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org ED9628136F Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by smtp1.osuosl.org (Postfix) with ESMTPS id ED9628136F for ; Sun, 26 Feb 2023 14:49:25 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 29B34B80BD9; Sun, 26 Feb 2023 14:49:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7E6A9C4339B; Sun, 26 Feb 2023 14:49:21 +0000 (UTC) From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Date: Sun, 26 Feb 2023 09:48:21 -0500 Message-Id: <20230226144845.827893-13-sashal@kernel.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230226144845.827893-1-sashal@kernel.org> References: <20230226144845.827893-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677422962; bh=sB4qmt7A4dKezC7XbRxJu7JVBeriEdk0CE62+dhbjpU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j9+CiHhUjVX2m8BNHXbk4gvvuc0djIYwRxaqVzT7nFEK4VeFJBciA4t1VaLWgiil8 E51OOLcwM7N3rTKeGSchkXwuOFDlfwD34KT8zy5Ecwt0Bgwv7AJdS6pKy2AJPIUchf 2GzpzFb02NyfEZ9SflGYBLYuunAA7a9SwtB8r3xWm8vv76XNhD0M+uJJHP3jIS7pSE vsF4hHh7Jq0LGFFjJcQm61Bgty4JQT7blBghU+ATvkviqtRXyUuPFhPK4ns9fA5SgT MHE/pJ1o7NE6y7eerBj1XBz2fGyeSo1fcedwCSO+zsPejkcyD8JetDoRGnLKdkVS5A oqRM03XtVkDHQ== X-Mailman-Original-Authentication-Results: smtp1.osuosl.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=j9+CiHhU Subject: [Intel-wired-lan] [PATCH AUTOSEL 5.15 13/36] ice: restrict PTP HW clock freq adjustments to 100, 000, 000 PPB X-BeenThere: intel-wired-lan@osuosl.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sasha Levin , intel-wired-lan@lists.osuosl.org, Siddaraju DH , jesse.brandeburg@intel.com, richardcochran@gmail.com, edumazet@google.com, Tony Nguyen , netdev@vger.kernel.org, kuba@kernel.org, pabeni@redhat.com, davem@davemloft.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-wired-lan-bounces@osuosl.org Sender: "Intel-wired-lan" From: Siddaraju DH [ Upstream commit 8aa4318c3a122b8670bc09af142de3872ca63b88 ] The PHY provides only 39b timestamp. With current timing implementation, we discard lower 7b, leaving 32b timestamp. The driver reconstructs the full 64b timestamp by correlating the 32b timestamp with cached_time for performance. The reconstruction algorithm does both forward & backward interpolation. The 32b timeval has overflow duration of 2^32 counts ~= 4.23 second. Due to interpolation in both direction, its now ~= 2.125 second IIRC, going with at least half a duration, the cached_time is updated with periodic thread of 1 second (worst-case) periodicity. But the 1 second periodicity is based on System-timer. With PPB adjustments, if the 1588 timers increments at say double the rate, (2s in-place of 1s), the Nyquist rate/half duration sampling/update of cached_time with 1 second periodic thread will lead to incorrect interpolations. Hence we should restrict the PPB adjustments to at least half duration of cached_time update which translates to 500,000,000 PPB. Since the periodicity of the cached-time system thread can vary, it is good to have some buffer time and considering practicality of PPB adjustments, limiting the max_adj to 100,000,000. Signed-off-by: Siddaraju DH Tested-by: Gurucharan G (A Contingent worker at Intel) Signed-off-by: Tony Nguyen Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/ice/ice_ptp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c index 9b50e9e6042a5..4d7aa49b7c147 100644 --- a/drivers/net/ethernet/intel/ice/ice_ptp.c +++ b/drivers/net/ethernet/intel/ice/ice_ptp.c @@ -1090,7 +1090,7 @@ static void ice_ptp_set_caps(struct ice_pf *pf) snprintf(info->name, sizeof(info->name) - 1, "%s-%s-clk", dev_driver_string(dev), dev_name(dev)); info->owner = THIS_MODULE; - info->max_adj = 999999999; + info->max_adj = 100000000; info->adjtime = ice_ptp_adjtime; info->adjfine = ice_ptp_adjfine; info->gettimex64 = ice_ptp_gettimex64; -- 2.39.0 _______________________________________________ Intel-wired-lan mailing list Intel-wired-lan@osuosl.org https://lists.osuosl.org/mailman/listinfo/intel-wired-lan