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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B777DC433E0 for ; Fri, 5 Mar 2021 17:22:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 89607650A2 for ; Fri, 5 Mar 2021 17:22:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229446AbhCERVu (ORCPT ); Fri, 5 Mar 2021 12:21:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229512AbhCERVc (ORCPT ); Fri, 5 Mar 2021 12:21:32 -0500 Received: from mail-wr1-x435.google.com (mail-wr1-x435.google.com [IPv6:2a00:1450:4864:20::435]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C7DDC061756 for ; Fri, 5 Mar 2021 09:21:32 -0800 (PST) Received: by mail-wr1-x435.google.com with SMTP id h98so2879011wrh.11 for ; Fri, 05 Mar 2021 09:21:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=maxiluxsystems-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=JW5c1u4SWQMGxSS5sSyhEtgIh0KGdGvIu4dU/YzXaFI=; b=TpIa+mC2wALaSayznTKWnoZgxozg4My/Lh3/UkMzo/4qP6KYgew+vLAZZSXXlTQMDU SOyGbimZ3aKzTwiSwVTbot07LN9qzdFfzUVyGZRyson+khvVFuKNhDKkDh2gJD3H8Kaj Miw9dvXOx8XKaf322gNbWixCefjHTBtKxLYt2jS6/4Obay0J6Ns9cXhw1WxEcRU+gyh5 6ZXW5VB/UWsuUyifaZ7yuTNDo4ZOK+OFYqeoV7+jV33884hX8sQ5GqkXLrmn+zeQ7vcr bFZjobyiNkO3MX1SOHl+CUH5/mnUt+HlM1IpPmMlePsuBmhttt/5rOydso4HbzWwPMxq XhXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=JW5c1u4SWQMGxSS5sSyhEtgIh0KGdGvIu4dU/YzXaFI=; b=PIPxQ0jjkJ1ZknxNntMKOAIgVyuS1OedTv5xDMk+v6+JunV7JtWcc2quEgwc6na/7Z HXJI0WB3D0CPtaGXUzw6OPGKB4Itc2TEv887f5i/gpwcSa45HeMLmoImSlZoPjFRQOzb /N82IOMSvy3fqQhvcY/xsSDriby7IeEKzSNhACZNqjTirFV91hxkfleQvqkFktbV/ekJ zh615C5jfmadfeCYVxx/e2d63+5+1lJeCVNJa/71KBxeIaSbVxO4Nas2UaonFwRTA4b0 uIGq5JA7jc/wrq0/XurUDzHMr64TA3vR21mZF3mzbfhU22fcPYutFRnpbAsQfKlwZMLh 974g== X-Gm-Message-State: AOAM5314dtlaLPx33reyix/DhVLc0K9tfAMZN3WEPnTTBOce4CbF+JnS FKNud5I30GGfasGNjzOGvlzssfnJCbfWxw== X-Google-Smtp-Source: ABdhPJxN5P3iS9P+8WdVPKBmf9ekunOIMhY2g/QJB6R1nVYuC97uXZgd/s8XsWBCO8xzL2PN5cwxgQ== X-Received: by 2002:adf:fd48:: with SMTP id h8mr10464693wrs.229.1614964890998; Fri, 05 Mar 2021 09:21:30 -0800 (PST) Received: from localhost.localdomain ([185.69.145.254]) by smtp.gmail.com with ESMTPSA id c9sm5174926wmb.33.2021.03.05.09.21.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 05 Mar 2021 09:21:30 -0800 (PST) From: Torin Cooper-Bennun To: linux-can@vger.kernel.org Cc: Marc Kleine-Budde , Pankaj Sharma , Torin Cooper-Bennun Subject: [PATCH 2/3] can: m_can: m_can_chip_config(): enable and configure internal timestamps Date: Fri, 5 Mar 2021 17:20:14 +0000 Message-Id: <20210305172015.1506525-3-torin@maxiluxsystems.com> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210305172015.1506525-1-torin@maxiluxsystems.com> References: <20210305172015.1506525-1-torin@maxiluxsystems.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org This is a prerequisite for transitioning the m_can driver to rx-offload, which works best with TX and RX timestamps. The timestamps provided by M_CAN are 16-bit, timed according to the nominal bit timing, and may be prescaled by a multiplier up to 16. We choose the highest prescalar so that the timestamp wraps every 2^20 bit times, or 209 ms at a bus speed of 5 Mbit/s. Timestamps will have a precision of 16 bit times. Signed-off-by: Torin Cooper-Bennun --- drivers/net/can/m_can/m_can.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index ea79cf0640a8..83a673417e7c 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1139,6 +1139,7 @@ static int m_can_set_bittiming(struct net_device *dev) * - >= v3.1.x: TX FIFO is used * - configure mode * - setup bittiming + * - configure timestamp generation */ static void m_can_chip_config(struct net_device *dev) { @@ -1250,6 +1251,11 @@ static void m_can_chip_config(struct net_device *dev) /* set bittiming params */ m_can_set_bittiming(dev); + /* enable internal timestamp generation, with a prescalar of 16. The + * prescalar is applied to the nominal bit timing */ + m_can_write(cdev, M_CAN_TSCC, + (0xf << TSCC_TCP_SHIFT) | TSCC_TSS_INTERNAL); + m_can_config_endisable(cdev, false); if (cdev->ops->init) -- 2.30.1