From patchwork Thu Jan 19 13:29:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bartosz Golaszewski X-Patchwork-Id: 9525737 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 25FB36020B for ; Thu, 19 Jan 2017 13:34:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1721627B2F for ; Thu, 19 Jan 2017 13:34:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0ABD927FBE; Thu, 19 Jan 2017 13:34:10 +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=-0.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_SORBS_SPAM, RDNS_NONE, T_DKIM_INVALID autolearn=no version=3.3.1 Received: from bombadil.infradead.org (unknown [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 963BF27B2F for ; Thu, 19 Jan 2017 13:34:09 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1cUCqq-0004vh-1d; Thu, 19 Jan 2017 13:34:04 +0000 Received: from mail-wm0-f47.google.com ([74.125.82.47]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cUCoJ-0000hc-Jf for linux-arm-kernel@lists.infradead.org; Thu, 19 Jan 2017 13:31:32 +0000 Received: by mail-wm0-f47.google.com with SMTP id f73so5842911wmf.1 for ; Thu, 19 Jan 2017 05:31:07 -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=gjYAUx7cCSy+KrACbqFxG1BPaNYntYNoHa+KVUCPqgQ=; b=MwFI9ahteYl7ojLdqz37PDbhKNxyHlA4sdUBL/ZGw6rJJXokLhlZk98+gjFJEv5vti a4B9KMLoJ/UMLfStf+e8jAFmX5wvd1QEXepA1UD7Bll6Ca43Yr7n2xbT3zV9aPs6CBc3 LVAUw7LKUDF0qfXrimM2BOjVkO4Rnf+njLZQl+1lUbh/d8OGiWe990ahZ19BOOaoZV7L S6TDZ5oWJEtA91D7MwBoyZLdG1ZVJSqW5rGhNQGxgOqLyzk0ARaVdO49DKPvFIKZ+Q8y NqLW7B/uRCGE6d038PkckwJhlhvbdepCkfvl1OrhKC4bRbl5Io0uF1O/lpAsSFG3KKvQ NKLA== 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=gjYAUx7cCSy+KrACbqFxG1BPaNYntYNoHa+KVUCPqgQ=; b=TGTlO/0II7Zt5UPx56vdI15GRRT/SCmQ5cCFPuOtqh8G2QoBonCHaDiNxTlzqbmaq4 NT9vXJGYC9708tHhtx+eFZU8RajxcbV2/ZL+BWj6BxLp/tS8jj2mE91hKQKUJUUqXf2/ tV8ov729Zmy/AvN+6e7yQ6cjYErzHovy936CE2pkebXQEcF1lfFhYYFu5EniivjIaIXy TLhTZQInz45oRGW5gr9IiBAJuE22S1HYewV9XC1ewiRJhJ0GfeuB60DK7hvwO1zQ+gom PQP0sYdw7Vw934JLLMDktl/OFaydu1fUdOmgnQW2+rIXAu8vZV1PXT6AEpPyJs64PewZ Y5Yg== X-Gm-Message-State: AIkVDXIfhm75BtF0wNUNx4MXzt/+rrWKrUdKZPidicDBnRsgmSjhr6B6/kJJOxG397oJtcgY X-Received: by 10.223.165.17 with SMTP id i17mr9055891wrb.62.1484832605740; Thu, 19 Jan 2017 05:30:05 -0800 (PST) Received: from localhost.localdomain ([90.63.244.31]) by smtp.gmail.com with ESMTPSA id c202sm53251996wmd.10.2017.01.19.05.30.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 19 Jan 2017 05:30:05 -0800 (PST) From: Bartosz Golaszewski To: Kevin Hilman , Sekhar Nori , Patrick Titiano , Michael Turquette , Tejun Heo , Rob Herring , Mark Rutland , Russell King , David Lechner Subject: [PATCH v4 10/14] sata: ahci-da850: add a workaround for controller instability Date: Thu, 19 Jan 2017 14:29:44 +0100 Message-Id: <1484832588-18413-11-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> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170119_053127_917597_BA9F009D X-CRM114-Status: GOOD ( 17.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-ide@vger.kernel.org, Bartosz Golaszewski , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org 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 We have a use case with the da850 SATA controller where at PLL0 frequency of 456MHz (needed to properly service the LCD controller) the chip becomes unstable and the hardreset operation is ignored the first time 50% of times. The sata core driver already retries to resume the link because some controllers ignore writes to the SControl register, but just retrying the resume operation doesn't work - we need to issue he phy/wake reset again to make it work. Reimplement ahci_hardreset() in the driver and poke the controller a couple times before really giving up. Signed-off-by: Bartosz Golaszewski --- drivers/ata/ahci_da850.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/drivers/ata/ahci_da850.c b/drivers/ata/ahci_da850.c index 11dd87e..0b2b1a4 100644 --- a/drivers/ata/ahci_da850.c +++ b/drivers/ata/ahci_da850.c @@ -16,7 +16,8 @@ #include #include "ahci.h" -#define DRV_NAME "ahci_da850" +#define DRV_NAME "ahci_da850" +#define HARDRESET_RETRIES 5 /* SATA PHY Control Register offset from AHCI base */ #define SATA_P0PHYCR_REG 0x178 @@ -76,6 +77,29 @@ static int ahci_da850_softreset(struct ata_link *link, return ret; } +static int ahci_da850_hardreset(struct ata_link *link, + unsigned int *class, unsigned long deadline) +{ + int ret, retry = HARDRESET_RETRIES; + bool online; + + /* + * In order to correctly service the LCD controller of the da850 SoC, + * we increased the PLL0 frequency to 456MHz from the default 300MHz. + * + * This made the SATA controller unstable and the hardreset operation + * does not always succeed the first time. Before really giving up to + * bring up the link, retry the reset a couple times. + */ + do { + ret = ahci_do_hardreset(link, class, deadline, &online); + if (online) + return ret; + } while (retry--); + + return ret; +} + static struct ata_port_operations ahci_da850_port_ops = { .inherits = &ahci_platform_ops, .softreset = ahci_da850_softreset, @@ -83,6 +107,8 @@ static struct ata_port_operations ahci_da850_port_ops = { * No need to override .pmp_softreset - it's only used for actual * PMP-enabled ports. */ + .hardreset = ahci_da850_hardreset, + .pmp_hardreset = ahci_da850_hardreset, }; static const struct ata_port_info ahci_da850_port_info = {