From patchwork Fri Jan 20 11:22:01 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bartosz Golaszewski X-Patchwork-Id: 9528039 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 8AFB06020B for ; Fri, 20 Jan 2017 11:25:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7BF8B201F5 for ; Fri, 20 Jan 2017 11:25:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 70E8C285F5; Fri, 20 Jan 2017 11:25:49 +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=-1.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_SORBS_SPAM,T_DKIM_INVALID autolearn=no version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [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 274FE201F5 for ; Fri, 20 Jan 2017 11:25:49 +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 1cUXK7-0002B2-5P; Fri, 20 Jan 2017 11:25:39 +0000 Received: from mail-wm0-f46.google.com ([74.125.82.46]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cUXIB-00067n-MY for linux-arm-kernel@lists.infradead.org; Fri, 20 Jan 2017 11:23:43 +0000 Received: by mail-wm0-f46.google.com with SMTP id d140so13253986wmd.0 for ; Fri, 20 Jan 2017 03:23:21 -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=lQjvzmcuNFxVfWzGb9Un9cJlVCz+EI2dQS1pEVoTf4scYXk2xvailt3o/tqdZHPWHS RA267ZDILv9uOkLXIBDFkvJxi5bBFXo8EM/40lWETkulb7ysanKaMzWyB4K7icO6g48W eBFPdcvRhG8ozlJhmUR2bSoQ9xRwrbFqCiPMVMCn5Gtk/43ZM8eNADL+Z6hvi6utZEvv 7yQFxL1cz1/hAg+Vt0ZeietaSnmDLC1ES5f4NNGJ3l1MdbuScQ5dUP0lo2x2xcCJ2d0F BHyK2s6CzX6yUDagCyHRz0Pf65O7pZzPOO4YYKpvw4TJpIretJac1UQwv4csPrHIr0SL vMRw== 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=Z1ykM+p1zuI+raHiuoRmSfQo5x3WJjDJiEeqaJGUHYdTaNoOdQEBTCTvgJ0iJ/LG38 KAp0Mcy7AtsBVru7D4AsjZSqbNNb+NjHgzotkDWVzcE35C50roQYP2UGgsloPHRUgJXM ygI2rLeyv0YDGLKJfeEewcEDLNw+QTi9xyFwEIED5hvz/UO0Z/fMgiw2t1gcMcIBzTvS bbNm6QD6w5gyY3pqhkZKXJjTMEAQSEjCyyiOVBIMdNb/ZuUxGDy5Cu3FL+GX7DKu6jff HtLt0qvSCFGG9QUMjAJSgCbqoVVDWqG10yRBM1eG9GdXGjSK4mCK/ztUoCzlhvWeD4LE viFg== X-Gm-Message-State: AIkVDXLQCROKVbn0kQUABvQV4GKgb6gc4zZzWxZqHkVu7sw2aw5g97Kotvgqp7Ctnj8vzGT1 X-Received: by 10.223.168.111 with SMTP id l102mr11121189wrc.150.1484911340308; Fri, 20 Jan 2017 03:22:20 -0800 (PST) Received: from localhost.localdomain ([90.63.244.31]) by smtp.gmail.com with ESMTPSA id l74sm5482402wmg.2.2017.01.20.03.22.19 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 20 Jan 2017 03:22:19 -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 v5 10/14] sata: ahci-da850: add a workaround for controller instability Date: Fri, 20 Jan 2017 12:22:01 +0100 Message-Id: <1484911325-23425-11-git-send-email-bgolaszewski@baylibre.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1484911325-23425-1-git-send-email-bgolaszewski@baylibre.com> References: <1484911325-23425-1-git-send-email-bgolaszewski@baylibre.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170120_032340_130453_A30E7B06 X-CRM114-Status: GOOD ( 16.47 ) 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 = {