From patchwork Thu Apr 23 23:01:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anson Huang X-Patchwork-Id: 11506779 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 706F792A for ; Thu, 23 Apr 2020 23:09:57 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4421020CC7 for ; Thu, 23 Apr 2020 23:09:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="VyRGrXVm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4421020CC7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nxp.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Owner; bh=Ln5FEZO2rd23FV7SoMDHhBmfgd3dAup0pUG5rPXFRO8=; b=VyR GrXVmcxSnsnJayri11Riahqr2x2yn5xTbw53s0XW3cKYuvQ19NdQJCTO5L32tvsf2Ao9hOIatemNW ZQjgDM6Sf2pKi9oqZV/EvfbCeq3JyFHtz8fvOJFa6VapdMqrP1/bPKNYaGoHMG9OAsTwem9lvdRId nhFxdVJspPj6Vmhma+ev0cCn8tnQLyhNYruuB742GP/bGnm+e2uDFms9JxxQ0YKZJIXvQezFnqbV4 pBvE4u/tvWlPMHtDFaWa7K7i2ADo0nZxHNXRkuNICkzr5F6zk/fWGhIMvjRozjyqAYoB5ltVq65s1 zrf3DUZs0tArvuAwAN8sbxCYp19q8Tg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRkyd-0000rU-3K; Thu, 23 Apr 2020 23:09:51 +0000 Received: from inva021.nxp.com ([92.121.34.21]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRkya-0000fn-1g for linux-arm-kernel@lists.infradead.org; Thu, 23 Apr 2020 23:09:49 +0000 Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 8AB5E20013D; Fri, 24 Apr 2020 01:09:45 +0200 (CEST) Received: from invc005.ap-rdc01.nxp.com (invc005.ap-rdc01.nxp.com [165.114.16.14]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 16560200143; Fri, 24 Apr 2020 01:09:42 +0200 (CEST) Received: from localhost.localdomain (shlinux2.ap.freescale.net [10.192.224.44]) by invc005.ap-rdc01.nxp.com (Postfix) with ESMTP id 7513240246; Fri, 24 Apr 2020 07:09:37 +0800 (SGT) From: Anson Huang To: jassisinghbrar@gmail.com, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH] mailbox: imx: Add context save/restore for suspend/resume Date: Fri, 24 Apr 2020 07:01:11 +0800 Message-Id: <1587682871-528-1-git-send-email-Anson.Huang@nxp.com> X-Mailer: git-send-email 2.7.4 X-Virus-Scanned: ClamAV using ClamSMTP X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200423_160948_229206_A42DB25E X-CRM114-Status: UNSURE ( 9.52 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on bombadil.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [92.121.34.21 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Linux-imx@nxp.com MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org For "mem" mode suspend on i.MX8 SoCs, MU settings could be lost because its power is off, so save/restore is needed for MU settings during suspend/resume. However, the restore can ONLY be done when MU settings are actually lost, for the scenario of settings NOT lost in "freeze" mode suspend, since there could be still IPC going on multiple CPUs, restoring the MU settings could overwrite the TIE by mistake and cause system freeze, so need to make sure ONLY restore the MU settings when it is powered off. Signed-off-by: Anson Huang --- drivers/mailbox/imx-mailbox.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/drivers/mailbox/imx-mailbox.c b/drivers/mailbox/imx-mailbox.c index 97bf0ac..b53cf63 100644 --- a/drivers/mailbox/imx-mailbox.c +++ b/drivers/mailbox/imx-mailbox.c @@ -67,6 +67,8 @@ struct imx_mu_priv { struct clk *clk; int irq; + u32 xcr; + bool side_b; }; @@ -583,12 +585,45 @@ static const struct of_device_id imx_mu_dt_ids[] = { }; MODULE_DEVICE_TABLE(of, imx_mu_dt_ids); +static int imx_mu_suspend_noirq(struct device *dev) +{ + struct imx_mu_priv *priv = dev_get_drvdata(dev); + + priv->xcr = imx_mu_read(priv, priv->dcfg->xCR); + + return 0; +} + +static int imx_mu_resume_noirq(struct device *dev) +{ + struct imx_mu_priv *priv = dev_get_drvdata(dev); + + /* + * ONLY restore MU when context lost, the TIE could + * be set during noirq resume as there is MU data + * communication going on, and restore the saved + * value will overwrite the TIE and cause MU data + * send failed, may lead to system freeze. This issue + * is observed by testing freeze mode suspend. + */ + if (!imx_mu_read(priv, priv->dcfg->xCR)) + imx_mu_write(priv, priv->xcr, priv->dcfg->xCR); + + return 0; +} + +static const struct dev_pm_ops imx_mu_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq, + imx_mu_resume_noirq) +}; + static struct platform_driver imx_mu_driver = { .probe = imx_mu_probe, .remove = imx_mu_remove, .driver = { .name = "imx_mu", .of_match_table = imx_mu_dt_ids, + .pm = &imx_mu_pm_ops, }, }; module_platform_driver(imx_mu_driver);