From patchwork Tue Jun 7 22:44:35 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 9162749 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id E07FE60467 for ; Tue, 7 Jun 2016 22:47:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D179328360 for ; Tue, 7 Jun 2016 22:47:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C4DE728370; Tue, 7 Jun 2016 22:47:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 76D7428369 for ; Tue, 7 Jun 2016 22:47:37 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1bAPkv-0005oB-Nb; Tue, 07 Jun 2016 22:45:53 +0000 Received: from mail-pf0-x234.google.com ([2607:f8b0:400e:c00::234]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1bAPkZ-0005Qi-CE for linux-arm-kernel@lists.infradead.org; Tue, 07 Jun 2016 22:45:32 +0000 Received: by mail-pf0-x234.google.com with SMTP id y124so22387391pfy.0 for ; Tue, 07 Jun 2016 15:45:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=jbYKd8N6OgZrUj0ZlPhwdbp3i6n6+p5uiJT3wZHNPHU=; b=kdyilJUFy7XPPxg8NdRs2EfVc0vpXgFj/6DE0TvzsxTCUZSGcAdotWj9QENWKaFNEh 5jDnUQlVbCPkDeZkzy4NOwl9xJyXO07aIy2Av7X/oGzXkPJU2DnNhbKcFfJbOIFsZ6VI UPPzJWWieeE6mS+PEavtAVQIkwZPB9G3mJyTE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=jbYKd8N6OgZrUj0ZlPhwdbp3i6n6+p5uiJT3wZHNPHU=; b=fS5ZJ52GtF1Bjhj7n2/hcvDtt/bwSAH2okLqDkTadJ0+E/B84gdzdBdzyOcMtJmcK4 CJ6CnI56l5TzSUXn3r+RSU0b4VfMhP+xoTb33HTWhwsU62adsGMvHeX+mb2J0BYJKD3V +rHPSOjgb8/M24l8lxcnCWCbJlN4PTEzYbBjxQ1bNl/T3Milg6cSN8KFynVYZc/bgxF6 A8jCWvJWrWtzdVMe0VAbsvcYOgy+JMzivIc1ou1LvH1mxaJpLM7Z9LwqhzTYkV9tHnd8 +LnrTucBBGRaws7xZXQEt0/BIQe5V9WvvSCw2c/hTsHHxDexz7mIoKKc32MpSouPfDWJ d3PA== X-Gm-Message-State: ALyK8tIC/gIV+XFNaK770xiFekZJ07ugGAZjB2UrIoF16zKeSd1t4pzlZd2oquB5XA9egGVM X-Received: by 10.98.88.69 with SMTP id m66mr1922545pfb.68.1465339510454; Tue, 07 Jun 2016 15:45:10 -0700 (PDT) Received: from tictac.mtv.corp.google.com ([172.22.65.76]) by smtp.gmail.com with ESMTPSA id 4sm37641782pfm.15.2016.06.07.15.45.09 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 07 Jun 2016 15:45:10 -0700 (PDT) From: Douglas Anderson To: ulf.hansson@linaro.org, kishon@ti.com, Heiko Stuebner , robh+dt@kernel.org Subject: [PATCH 02/11] mmc: sdhci-of-arasan: Always power the PHY off/on when clock changes Date: Tue, 7 Jun 2016 15:44:35 -0700 Message-Id: <1465339484-969-3-git-send-email-dianders@chromium.org> X-Mailer: git-send-email 2.8.0.rc3.226.g39d4020 In-Reply-To: <1465339484-969-1-git-send-email-dianders@chromium.org> References: <1465339484-969-1-git-send-email-dianders@chromium.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160607_154531_554230_FAF00D74 X-CRM114-Status: GOOD ( 19.68 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, xzy.xu@rock-chips.com, linux-kernel@vger.kernel.org, shawn.lin@rock-chips.com, briannorris@chromium.org, linux-mmc@vger.kernel.org, adrian.hunter@intel.com, Douglas Anderson , linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, michal.simek@xilinx.com, soren.brinkmann@xilinx.com MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In commit 802ac39a5566 ("mmc: sdhci-of-arasan: fix set_clock when a phy is supported") we added code to power the PHY off and on whenever the clock was changed but we avoided doing the power cycle code when the clock was low speed. Let's now do it always. Although there may be other reasons for power cycling the PHY when the clock changes, one of the main reasons is that we need to give the DLL a chance to re-lock with the new clock. One of the things that the DLL is for is tuning the Receive Clock in HS200 mode and STRB in HS400 mode. Thus it is clear that we should make sure we power cycle the PHY (and wait for the DLL to lock) when we know we'll be in one of these two speed modes. That's what the original code did, though it used the clock rate rather than the speed mode. However, even in speed modes other than HS200,/HS400 the DLL is used for something since it can be clearly observed that the PHY doesn't function properly if you leave the DLL off. Although it appears less important to power cycle the PHY and wait for the DLL to lock when not in HS200/HS400 modes (no bugs were reported), it still seems wise to let the locking always happen nevertheless. Note: as part of this, we make sure that we never try to turn the PHY on when the clock is off (when the clock rate is 0). The PHY cannot work when the clock is off since its DLL can't lock. This change requires ("phy: rockchip-emmc: Increase lock time allowance") and will cause problems if picked without that change. Signed-off-by: Douglas Anderson --- drivers/mmc/host/sdhci-of-arasan.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c index 533e2bcb10bc..3ff1711077c2 100644 --- a/drivers/mmc/host/sdhci-of-arasan.c +++ b/drivers/mmc/host/sdhci-of-arasan.c @@ -35,11 +35,13 @@ /** * struct sdhci_arasan_data * @clk_ahb: Pointer to the AHB clock - * @phy: Pointer to the generic phy + * @phy: Pointer to the generic phy + * @phy_on: True if the PHY is turned on. */ struct sdhci_arasan_data { struct clk *clk_ahb; struct phy *phy; + bool phy_on; }; static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host) @@ -61,12 +63,10 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock) { struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host); - bool ctrl_phy = false; - if (clock > MMC_HIGH_52_MAX_DTR && (!IS_ERR(sdhci_arasan->phy))) - ctrl_phy = true; + if (sdhci_arasan->phy_on && !IS_ERR(sdhci_arasan->phy)) { + sdhci_arasan->phy_on = false; - if (ctrl_phy) { spin_unlock_irq(&host->lock); phy_power_off(sdhci_arasan->phy); spin_lock_irq(&host->lock); @@ -74,7 +74,9 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock) sdhci_set_clock(host, clock); - if (ctrl_phy) { + if (host->mmc->actual_clock && !IS_ERR(sdhci_arasan->phy)) { + sdhci_arasan->phy_on = true; + spin_unlock_irq(&host->lock); phy_power_on(sdhci_arasan->phy); spin_lock_irq(&host->lock); @@ -257,12 +259,6 @@ static int sdhci_arasan_probe(struct platform_device *pdev) goto clk_disable_all; } - ret = phy_power_on(sdhci_arasan->phy); - if (ret < 0) { - dev_err(&pdev->dev, "phy_power_on err.\n"); - goto err_phy_power; - } - host->mmc_host_ops.hs400_enhanced_strobe = sdhci_arasan_hs400_enhanced_strobe; } @@ -275,9 +271,6 @@ static int sdhci_arasan_probe(struct platform_device *pdev) err_add_host: if (!IS_ERR(sdhci_arasan->phy)) - phy_power_off(sdhci_arasan->phy); -err_phy_power: - if (!IS_ERR(sdhci_arasan->phy)) phy_exit(sdhci_arasan->phy); clk_disable_all: clk_disable_unprepare(clk_xin);