From patchwork Thu Jan 19 13:29:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bartosz Golaszewski X-Patchwork-Id: 717070 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3v44X400hvz9s5g for ; Fri, 20 Jan 2017 00:32:36 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=baylibre-com.20150623.gappssmtp.com header.i=@baylibre-com.20150623.gappssmtp.com header.b="zir4cQI1"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752694AbdASNbb (ORCPT ); Thu, 19 Jan 2017 08:31:31 -0500 Received: from mail-wm0-f47.google.com ([74.125.82.47]:37617 "EHLO mail-wm0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752419AbdASNbI (ORCPT ); Thu, 19 Jan 2017 08:31:08 -0500 Received: by mail-wm0-f47.google.com with SMTP id c206so77301733wme.0 for ; Thu, 19 Jan 2017 05:30:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=R5PNJOuUNZ0TgS4mS+ALb4UY8CbowzkiyfRTK/S7H2U=; b=zir4cQI1KtaNi2xBDuOLT4y3AMPo4wlrFa91ruFbVEsg3XREHOjlr+wUIJM4sA0J2o IadhnUauLY/dU7rK/tW9J+jVxOP5KUGOjfAsyYyElog5lFSXS+k8Tgl0QuodlGgri7IC NCBbaT3WyoXhJ2vcxzc/F8EJLIh9Vg2HAfVzP+oXaigRRugQPCKLSezoxZFMDYCDO+/O AKGNngLUwzZyt3biOkx/RwNSa/pS+P0SFXMMpBJm+7nI8ftCz4qh2+bSEJPBYCFvNlj3 QlbsbVUalhQTJZ7LmV6fa+swJuXxylXSbAWZ5OJJBqTfr7nMHcXysFX/GToN4mX0oNDz MMVg== 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; bh=R5PNJOuUNZ0TgS4mS+ALb4UY8CbowzkiyfRTK/S7H2U=; b=cs47xuG6TtFtmYEPK2CsUK3Zm4Nu17u/FMKQL3MPLFuXCuqpSiio+SQzhdqt6WlTz9 jHBQSjf/fbm2MkhZRV/Ymr1AJT55c0ubBH6RMzgNuU18GP4+y5lR+C2KbwOgK0+VFi4t tacisdXyCum5YFqaEW6gyGLIvHekrFtSwq/DrWA0O/uG+iXcAFTjmgLPfaV3NvwFnlKV qOGgMuV8rknU7G74OflMVRJVn+BfsbUJOjg5JIO49rkHbCdzoRGgOOjDfeolaIR2Vkyv 2BZ8yM+7jHMlGm9wcRzZjihXe+i89hG7dDRQgVRMzKvL1kjd9tgT5zfiLMRDM60mpf5G DKFA== X-Gm-Message-State: AIkVDXKMYNTSzdbYdCyRj9Meep6azW6ZgCqeTsJqkDD2A2F797wJGK+wSOVweCPm6emR+eWT X-Received: by 10.28.230.91 with SMTP id d88mr16245287wmh.129.1484832607052; Thu, 19 Jan 2017 05:30:07 -0800 (PST) Received: from localhost.localdomain ([90.63.244.31]) by smtp.gmail.com with ESMTPSA id c202sm53251996wmd.10.2017.01.19.05.30.05 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 19 Jan 2017 05:30:06 -0800 (PST) From: Bartosz Golaszewski To: Kevin Hilman , Sekhar Nori , Patrick Titiano , Michael Turquette , Tejun Heo , Rob Herring , Mark Rutland , Russell King , David Lechner Cc: linux-ide@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Bartosz Golaszewski Subject: [PATCH v4 11/14] sata: ahci-da850: un-hardcode the MPY bits Date: Thu, 19 Jan 2017 14:29:45 +0100 Message-Id: <1484832588-18413-12-git-send-email-bgolaszewski@baylibre.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1484832588-18413-1-git-send-email-bgolaszewski@baylibre.com> References: <1484832588-18413-1-git-send-email-bgolaszewski@baylibre.com> Sender: linux-ide-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org All platforms using this driver now register the SATA refclk. Remove the hardcoded default value from the driver and instead read the rate of the external clock and calculate the required MPY value from it. Signed-off-by: Bartosz Golaszewski --- drivers/ata/ahci_da850.c | 91 ++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 76 insertions(+), 15 deletions(-) diff --git a/drivers/ata/ahci_da850.c b/drivers/ata/ahci_da850.c index 0b2b1a4..9ed404d 100644 --- a/drivers/ata/ahci_da850.c +++ b/drivers/ata/ahci_da850.c @@ -29,17 +29,8 @@ #define SATA_PHY_TXSWING(x) ((x) << 19) #define SATA_PHY_ENPLL(x) ((x) << 31) -/* - * The multiplier needed for 1.5GHz PLL output. - * - * NOTE: This is currently hardcoded to be suitable for 100MHz crystal - * frequency (which is used by DA850 EVM board) and may need to be changed - * if you would like to use this driver on some other board. - */ -#define DA850_SATA_CLK_MULTIPLIER 7 - static void da850_sata_init(struct device *dev, void __iomem *pwrdn_reg, - void __iomem *ahci_base) + void __iomem *ahci_base, u32 mpy) { unsigned int val; @@ -48,13 +39,61 @@ static void da850_sata_init(struct device *dev, void __iomem *pwrdn_reg, val &= ~BIT(0); writel(val, pwrdn_reg); - val = SATA_PHY_MPY(DA850_SATA_CLK_MULTIPLIER + 1) | SATA_PHY_LOS(1) | - SATA_PHY_RXCDR(4) | SATA_PHY_RXEQ(1) | SATA_PHY_TXSWING(3) | - SATA_PHY_ENPLL(1); + val = SATA_PHY_MPY(mpy) | SATA_PHY_LOS(1) | SATA_PHY_RXCDR(4) | + SATA_PHY_RXEQ(1) | SATA_PHY_TXSWING(3) | SATA_PHY_ENPLL(1); writel(val, ahci_base + SATA_P0PHYCR_REG); } +static u32 ahci_da850_calculate_mpy(unsigned long refclk_rate) +{ + u32 pll_output = 1500000000, needed; + + /* + * We need to determine the value of the multiplier (MPY) bits. + * In order to include the 12.5 multiplier we need to first divide + * the refclk rate by ten. + * + * __div64_32() turned out to be unreliable, sometimes returning + * false results. + */ + WARN((refclk_rate % 10) != 0, "refclk must be divisible by 10"); + needed = pll_output / (refclk_rate / 10); + + /* + * What we have now is (multiplier * 10). + * + * Let's determine the actual register value we need to write. + */ + + switch (needed) { + case 50: + return 0x1; + case 60: + return 0x2; + case 80: + return 0x4; + case 100: + return 0x5; + case 120: + return 0x6; + case 125: + return 0x7; + case 150: + return 0x8; + case 200: + return 0x9; + case 250: + return 0xa; + default: + /* + * We should have divided evenly - if not, return an invalid + * value. + */ + return 0; + } +} + static int ahci_da850_softreset(struct ata_link *link, unsigned int *class, unsigned long deadline) { @@ -126,9 +165,10 @@ static int ahci_da850_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct ahci_host_priv *hpriv; - struct resource *res; void __iomem *pwrdn_reg; + struct resource *res; struct clk *clk; + u32 mpy; int rc; hpriv = ahci_platform_get_resources(pdev); @@ -150,6 +190,27 @@ static int ahci_da850_probe(struct platform_device *pdev) hpriv->clks[0] = clk; } + /* + * The second clock used by ahci-da850 is the external REFCLK. If we + * didn't get it from ahci_platform_get_resources(), let's try to + * specify the con_id in clk_get(). + */ + if (!hpriv->clks[1]) { + clk = clk_get(dev, "refclk"); + if (IS_ERR(clk)) { + dev_err(dev, "unable to obtain the reference clock"); + return -ENODEV; + } else { + hpriv->clks[1] = clk; + } + } + + mpy = ahci_da850_calculate_mpy(clk_get_rate(hpriv->clks[1])); + if (mpy == 0) { + dev_err(dev, "invalid REFCLK multiplier value: 0x%x", mpy); + return -EINVAL; + } + rc = ahci_platform_enable_resources(hpriv); if (rc) return rc; @@ -162,7 +223,7 @@ static int ahci_da850_probe(struct platform_device *pdev) if (!pwrdn_reg) goto disable_resources; - da850_sata_init(dev, pwrdn_reg, hpriv->mmio); + da850_sata_init(dev, pwrdn_reg, hpriv->mmio, mpy); rc = ahci_platform_init_host(pdev, hpriv, &ahci_da850_port_info, &ahci_platform_sht);