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 9050EC6FA8E for ; Sun, 26 Feb 2023 14:45:42 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 332DB4061F; Sun, 26 Feb 2023 14:45:42 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 332DB4061F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osuosl.org; s=default; t=1677422742; bh=4MQfhbwpeUEgx6iZ2yxfh+HE5sNk0QV6Hph6KO+S1S0=; h=From:To:Date:In-Reply-To:References:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: Cc:From; b=aANvI/2vNnSMXwSc0zWG6Eb178IL0fTxPFY/JIr/7DzpOHCc0PaA2jtmZIU5aDFTh QdHS+jwxO9tTOaABoO+s8rZGdIjEg6ppaZ+94RNiWSKtdM3zucaY0p2WOgU0dMlPyq L+NJfKIyBUHclPW4EsGNJQAFBNyZ2+StHIPDdBOcma8GzWQM9JwJ/5guFPeR8X0aF/ Ys6XmF6gRlVzdAxoZ+4cUHMwEzWa5durr4InvrWEACw0rSVe7cnHVr4n9SWHlz9KOV CZ5M3WQps8UWpOM75X4n6fSrNidEm322s0Y5SLkV33wf+4bTQPNniSxioFAsN5UFo3 O+62W0BXyRKcA== 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 FUYADgCYAKHS; Sun, 26 Feb 2023 14:45:41 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by smtp2.osuosl.org (Postfix) with ESMTP id 310CB40396; Sun, 26 Feb 2023 14:45:41 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 310CB40396 Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by ash.osuosl.org (Postfix) with ESMTP id 001191BF41C for ; Sun, 26 Feb 2023 14:45:36 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id DA6F740860 for ; Sun, 26 Feb 2023 14:45:36 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org DA6F740860 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xRPjKp0kovQC for ; Sun, 26 Feb 2023 14:45:36 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org A14244085E Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by smtp4.osuosl.org (Postfix) with ESMTPS id A14244085E for ; Sun, 26 Feb 2023 14:45:35 +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 1B73FB80BE7; Sun, 26 Feb 2023 14:45:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B172C433EF; Sun, 26 Feb 2023 14:45:29 +0000 (UTC) From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Date: Sun, 26 Feb 2023 09:44:10 -0500 Message-Id: <20230226144446.824580-18-sashal@kernel.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230226144446.824580-1-sashal@kernel.org> References: <20230226144446.824580-1-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=1677422730; bh=ZrZh0ffHod44Z2tfuYGnD78a9b3uoNILJV5wnbaMdzA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kyYQZnG5QQJYDOgyj1mfMqle/w0CzSLCqc713x2gbtRSco7V3aV3whLZD9SvGiutM WcgPYcuD69HXp30y/pHNUUaxIADr3MnfQIkGm0isouNpt2ZcgpjnFdccb/ZJ73GAj/ 7564M6AH4SHzFGTsTRaQ4ScMfobAjbQmGajyDYrSsa5u2IAg2EcIbxGg2onMUqLBJ8 3LwP/2TwavHXAlQ1k7WVl8i2eghQYVz+5Ont7urHbkwG8M2wwZfGca5UkKlFtgzZXe uZQcSwwkUXmg8tOAs5eszflcKKK4+NaEbDy1ytpD2hswc2/lwXL+eH+mPwACX7UWM9 A4j7zNEhwWweg== X-Mailman-Original-Authentication-Results: smtp4.osuosl.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=kyYQZnG5 Subject: [Intel-wired-lan] [PATCH AUTOSEL 6.2 18/53] 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 d63161d73eb16..3abc8db1d0659 100644 --- a/drivers/net/ethernet/intel/ice/ice_ptp.c +++ b/drivers/net/ethernet/intel/ice/ice_ptp.c @@ -2269,7 +2269,7 @@ 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