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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 A2C4CC43331 for ; Thu, 5 Sep 2019 15:11:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0343B20828 for ; Thu, 5 Sep 2019 15:11:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388415AbfIEPLg (ORCPT ); Thu, 5 Sep 2019 11:11:36 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:49004 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731401AbfIEPLd (ORCPT ); Thu, 5 Sep 2019 11:11:33 -0400 Received: from reginn.horms.nl (watermunt.horms.nl [80.127.179.77]) by kirsty.vergenet.net (Postfix) with ESMTPA id 528EB25B82E; Fri, 6 Sep 2019 01:11:28 +1000 (AEST) Received: by reginn.horms.nl (Postfix, from userid 7100) id DC2D6940C33; Thu, 5 Sep 2019 17:11:25 +0200 (CEST) From: Simon Horman To: David Miller , Sergei Shtylyov Cc: Magnus Damm , netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Simon Horman Subject: [PATCH net-next v2 4/4] ravb: TROCR register is only present on R-Car Gen3 Date: Thu, 5 Sep 2019 17:10:59 +0200 Message-Id: <20190905151059.26794-5-horms+renesas@verge.net.au> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190905151059.26794-1-horms+renesas@verge.net.au> References: <20190905151059.26794-1-horms+renesas@verge.net.au> Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org Only use the TROCR register on R-Car Gen3 as it is not present on other SoCs. Offsets used for the undocumented registers are considered reserved and should not be written to. After some internal investigation with Renesas it remains unclear why this driver accesses these fields on R-Car Gen2 but regardless of what the historical reasons are the current code is considered incorrect. Signed-off-by: Simon Horman Reviewed-by: Yoshihiro Shimoda Acked-by: Sergei Shtylyov --- v2 * Accumulated tags * Updated changelog --- drivers/net/ethernet/renesas/ravb.h | 2 +- drivers/net/ethernet/renesas/ravb_main.c | 6 ++++-- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h index bdb051f04b0c..a9c89d5d8898 100644 --- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h @@ -193,7 +193,7 @@ enum ravb_reg { GECMR = 0x05b0, MAHR = 0x05c0, MALR = 0x05c8, - TROCR = 0x0700, /* Undocumented? */ + TROCR = 0x0700, /* R-Car Gen3 only */ CEFCR = 0x0740, FRECR = 0x0748, TSFRCR = 0x0750, diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index b538cc6fdbb7..de9aa8c47f1c 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -1621,8 +1621,10 @@ static struct net_device_stats *ravb_get_stats(struct net_device *ndev) stats0 = &priv->stats[RAVB_BE]; stats1 = &priv->stats[RAVB_NC]; - nstats->tx_dropped += ravb_read(ndev, TROCR); - ravb_write(ndev, 0, TROCR); /* (write clear) */ + if (priv->chip_id == RCAR_GEN3) { + nstats->tx_dropped += ravb_read(ndev, TROCR); + ravb_write(ndev, 0, TROCR); /* (write clear) */ + } nstats->rx_packets = stats0->rx_packets + stats1->rx_packets; nstats->tx_packets = stats0->tx_packets + stats1->tx_packets; -- 2.11.0