From patchwork Mon Jan 30 10:02:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bartosz Golaszewski X-Patchwork-Id: 9544635 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 AEF06604CC for ; Mon, 30 Jan 2017 10:08:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9888827E15 for ; Mon, 30 Jan 2017 10:08:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8D5BC27F90; Mon, 30 Jan 2017 10:08:02 +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 172B827E15 for ; Mon, 30 Jan 2017 10:08:02 +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 1cY8sJ-0006QF-5O; Mon, 30 Jan 2017 10:07:51 +0000 Received: from mail-wm0-f49.google.com ([74.125.82.49]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cY8oL-0001tq-FG for linux-arm-kernel@lists.infradead.org; Mon, 30 Jan 2017 10:03:47 +0000 Received: by mail-wm0-f49.google.com with SMTP id r141so25580908wmg.1 for ; Mon, 30 Jan 2017 02:03:27 -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=UuFqiL7UFZBOptYwa564ZJUFui00u+cvOWp5bQVJzCc=; b=a3g5iQdw6qca6x3ji1zxWQnRW7GmgCUQ4slFmC9wj8s7OwSHrGJLNU82IjgwRSocpX UKLygRXEkAa3AqhAHGqNd121v+oDKZdgfSXkv0EEZycYCz60yolMHYwe+p74mhlZP5eP OGgchtTPy7uj6mpNjdh2ndjS3gLd2DsX5Wsy3eRSl/CCMka/r8vc3NlDDlwxhqkna+OF b9i4RB7T/qFpmAPhVMEG2GQWiB0S2aQQsTjDGH65D0DAKW4WEfukNtpNw2eg8oBkJaSH F6U0Mb1QwhLgP/rGfKTF8b+yA+XZrLsMMud8HHPwiPX8X3Xempz0xke1aKxKXRywj/kh KBMQ== 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=UuFqiL7UFZBOptYwa564ZJUFui00u+cvOWp5bQVJzCc=; b=mCYH/Qcjj6CcnNeD280no7Uw4U+Mr0V5Up2E71tbInXQmbJarLN2UruPRRNw/Zr3SU Lp56RCasqFWYaPbX9mWUBmMmwGm/SqR1KHFLtwkpcusBC2AHEFBNaYej0n9k0L0eU+Iw sxTjq7hKWL123m/2SMXxv4jMS/WqXWoTy8or4ptPTQ5ivMGgy/H0OXu1HrN/EVaABpTR YBKwWFxYikHf2ICsvV0mhn5CWhIq1T+u/qelAYQ02aH2+qE7J0+GOqYny+QK55yNjNTv QGWMtIRXJpYtlI6Wo/fUelyhUvscTMgrkDzt4jV9rRBpWA6Od840RT4QWFMPrD6irex9 DcHg== X-Gm-Message-State: AIkVDXKG9d0Mpa2fs8+KWiNiC02v4gw0zmSSbekyq7KGqHoxNPkR5Xo2fMmIPJNKip97shK+ X-Received: by 10.28.62.144 with SMTP id l138mr12477911wma.50.1485770546091; Mon, 30 Jan 2017 02:02:26 -0800 (PST) Received: from localhost.localdomain ([90.63.244.31]) by smtp.gmail.com with ESMTPSA id j18sm21939536wrb.33.2017.01.30.02.02.24 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 30 Jan 2017 02:02:25 -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 v7 10/14] sata: ahci-da850: add a workaround for controller instability Date: Mon, 30 Jan 2017 11:02:07 +0100 Message-Id: <1485770531-6772-11-git-send-email-bgolaszewski@baylibre.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1485770531-6772-1-git-send-email-bgolaszewski@baylibre.com> References: <1485770531-6772-1-git-send-email-bgolaszewski@baylibre.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170130_020345_750289_B7BAD68F X-CRM114-Status: GOOD ( 17.15 ) 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 Acked-by: Tejun Heo --- 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 84c7805..d65088a 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 = {