From patchwork Tue May 26 16:22:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antoine Tenart X-Patchwork-Id: 218519 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=-9.8 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 C1608C433E0 for ; Tue, 26 May 2020 16:23:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AAF662073B for ; Tue, 26 May 2020 16:23:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730589AbgEZQX1 (ORCPT ); Tue, 26 May 2020 12:23:27 -0400 Received: from relay2-d.mail.gandi.net ([217.70.183.194]:41957 "EHLO relay2-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727110AbgEZQX0 (ORCPT ); Tue, 26 May 2020 12:23:26 -0400 X-Originating-IP: 90.76.143.236 Received: from localhost (lfbn-tou-1-1075-236.w90-76.abo.wanadoo.fr [90.76.143.236]) (Authenticated sender: antoine.tenart@bootlin.com) by relay2-d.mail.gandi.net (Postfix) with ESMTPSA id 475854000B; Tue, 26 May 2020 16:23:20 +0000 (UTC) From: Antoine Tenart To: davem@davemloft.net, andrew@lunn.ch, f.fainelli@gmail.com, hkallweit1@gmail.com Cc: Antoine Tenart , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, alexandre.belloni@bootlin.com, thomas.petazzoni@bootlin.com, allan.nielsen@microchip.com Subject: [PATCH net-next 3/4] net: phy: mscc-miim: improve waiting logic Date: Tue, 26 May 2020 18:22:55 +0200 Message-Id: <20200526162256.466885-4-antoine.tenart@bootlin.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526162256.466885-1-antoine.tenart@bootlin.com> References: <20200526162256.466885-1-antoine.tenart@bootlin.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The MSCC MIIM MDIO driver uses a waiting logic to wait for the MDIO bus to be ready to accept next commands. It does so by polling the BUSY status bit which indicates the MDIO bus has completed all pending operations. This can take time, and the controller supports writing the next command as soon as there are no pending commands (which happens while the MDIO bus is busy completing its current command). This patch implements this improved logic by adding an helper to poll the PENDING status bit, and by adjusting where we should wait for the bus to not be busy or to not be pending. Signed-off-by: Antoine Tenart --- drivers/net/phy/mdio-mscc-miim.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/net/phy/mdio-mscc-miim.c b/drivers/net/phy/mdio-mscc-miim.c index 42119f661452..aed9afa1e8f1 100644 --- a/drivers/net/phy/mdio-mscc-miim.c +++ b/drivers/net/phy/mdio-mscc-miim.c @@ -16,6 +16,7 @@ #include #define MSCC_MIIM_REG_STATUS 0x0 +#define MSCC_MIIM_STATUS_STAT_PENDING BIT(2) #define MSCC_MIIM_STATUS_STAT_BUSY BIT(3) #define MSCC_MIIM_REG_CMD 0x8 #define MSCC_MIIM_CMD_OPR_WRITE BIT(1) @@ -47,13 +48,23 @@ static int mscc_miim_wait_ready(struct mii_bus *bus) !(val & MSCC_MIIM_STATUS_STAT_BUSY), 50, 10000); } +static int mscc_miim_wait_pending(struct mii_bus *bus) +{ + struct mscc_miim_dev *miim = bus->priv; + u32 val; + + return readl_poll_timeout(miim->regs + MSCC_MIIM_REG_STATUS, val, + !(val & MSCC_MIIM_STATUS_STAT_PENDING), + 50, 10000); +} + static int mscc_miim_read(struct mii_bus *bus, int mii_id, int regnum) { struct mscc_miim_dev *miim = bus->priv; u32 val; int ret; - ret = mscc_miim_wait_ready(bus); + ret = mscc_miim_wait_pending(bus); if (ret) goto out; @@ -82,7 +93,7 @@ static int mscc_miim_write(struct mii_bus *bus, int mii_id, struct mscc_miim_dev *miim = bus->priv; int ret; - ret = mscc_miim_wait_ready(bus); + ret = mscc_miim_wait_pending(bus); if (ret < 0) goto out;