From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 75EC7C4332F for ; Sat, 5 Nov 2022 19:47:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=oLZ6B/Q1sgBVkzJFH+qEH36mZDpdfoyz9Gt/Xugnecc=; b=lOxBodm2eOG1WE 5erFpWieIBjvsyh0/tGzF9OKHXFzlRG9pvpq+aEEdxPO/fu/zoCifuwi5/3F1mF/LlkUENzKyB29y LXYkkw6n79w1Y4piOsJ+7Zlmodimr5RhhKv6H9Z/2zRgeKYdovWwK0gc2nvJy81unqGZW/TegAmyn /qEiuZ5pPCm8CYVcIg2IiXBW1o0B8svdupW1dhn6I39fGwpU+hM96aDm7gODJfokkcn3ucpthchUx xk1LAwk73B8wTsNjPBbG5H4M004r88p+9UGTKWBMgvjSwgWIGGPBOb1W+al83Xglr+1yB/N0yWAJi ruqRZUCz9+VtIobY9+ZA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1orP81-007AxN-Dn; Sat, 05 Nov 2022 19:46:53 +0000 Received: from mail-ej1-x62d.google.com ([2a00:1450:4864:20::62d]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1orP7y-007Awz-Or for linux-arm-kernel@lists.infradead.org; Sat, 05 Nov 2022 19:46:52 +0000 Received: by mail-ej1-x62d.google.com with SMTP id f27so21132776eje.1 for ; Sat, 05 Nov 2022 12:46:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Nq/APDJ1/i7tYioV5hUAkwvhILl5RMdNbxu0oP9Zowo=; b=S//juSlij40GbQm+UzMkx9pe4GilcX0yFl9N8MOVXy0tTuq4qH2Q1AG+0Ie8iKWUxS VBJWP+7nUAyZRKG6bNBFd9rgF5V90RsuevlhyKBBYUcxmeG/3rT9Y7H/O64Y+hgxyH4u n0Gfcet4L1YqOnm0Ie4M/tJ1K6AnrRR6rsAG6b2iMBAGeaTlXaWaOjRFaMproAB0Rfkd yGHFsshpwiinpJ4o7KUgcbNG5CFqJ5BLf0YlGlSHIBpMrzQn5wf9a9wKO2r1ja7bsx9V lnUb+VLJBFx+3IspDy467Ow5BA9AleexHDEPQYO3ODQFZ9XZmz9OZ89zqweESyIfBWOh K44A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Nq/APDJ1/i7tYioV5hUAkwvhILl5RMdNbxu0oP9Zowo=; b=Noo17syZRq38NCGFVfqOVF8Qgj6ekIfKsyyXaGpgVMqDH4TsM1A1GpZHGD76Sv8aPF VC6sdv8UJGvaL9YXgBQKEBhJK329WxxfGuW+ViMsXvTL0/UEhTQr3rGDPybkn7oYQHzf bRXRUqmk6LIl3srBTmDPnFUGxc3gMLiReqsUlEvyWZuwEgQB7FFgcDzyfY7xVkzlFj6a GUPXR5YdA+IOeXJxiCbr0DEGVkJ+dyYlvQ40vkkwxb/yN7rOftFruRkgCpNxpmOxaSfv HPc9PXHMStBTcCbyuZ2VN6x1DcnZkcmUpJUB65aDF+4lsCgbzMs/tWqWF8HcMtk/wrQF dK6Q== X-Gm-Message-State: ACrzQf0ipgHmoD3TpK442PcNrQ4JUjaH+A8EuxyxND/P/5/TtqDWC2yb Tmv0+SQY2M8EC9VQqo+Suvg= X-Google-Smtp-Source: AMsMyM7CA8//3SyAUldovN5OAm+KAnq+khm0KTenfTZP8RCbkkZJqClOrzFwOhDtIRpW7gkIliGmfg== X-Received: by 2002:a17:907:5c2:b0:77e:def7:65d8 with SMTP id wg2-20020a17090705c200b0077edef765d8mr41276589ejb.487.1667677608563; Sat, 05 Nov 2022 12:46:48 -0700 (PDT) Received: from jernej-laptop.localnet (89-212-118-115.static.t-2.net. [89.212.118.115]) by smtp.gmail.com with ESMTPSA id i24-20020a05640200d800b00463c367024bsm1557754edu.63.2022.11.05.12.46.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 05 Nov 2022 12:46:48 -0700 (PDT) From: Jernej =?utf-8?B?xaBrcmFiZWM=?= To: Chen-Yu Tsai , Samuel Holland Cc: Ivaylo Dimitrov , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, Samuel Holland Subject: Re: [PATCH 2/2] bus: sunxi-rsb: Support atomic transfers Date: Sat, 05 Nov 2022 20:46:47 +0100 Message-ID: <4779430.31r3eYUQgx@jernej-laptop> In-Reply-To: <20221105191954.14360-3-samuel@sholland.org> References: <20221105191954.14360-1-samuel@sholland.org> <20221105191954.14360-3-samuel@sholland.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221105_124650_859981_25319D3E X-CRM114-Status: GOOD ( 19.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Dne sobota, 05. november 2022 ob 20:19:53 CET je Samuel Holland napisal(a): > When communicating with a PMIC during system poweroff (pm_power_off()), > IRQs are disabled and we are in a RCU read-side critical section, so we > cannot use wait_for_completion_io_timeout(). Instead, poll the status > register for transfer completion. > > Signed-off-by: Samuel Holland > --- > > drivers/bus/sunxi-rsb.c | 23 +++++++++++++++++------ > 1 file changed, 17 insertions(+), 6 deletions(-) > > diff --git a/drivers/bus/sunxi-rsb.c b/drivers/bus/sunxi-rsb.c > index 17343cd75338..0f0e498d4379 100644 > --- a/drivers/bus/sunxi-rsb.c > +++ b/drivers/bus/sunxi-rsb.c > @@ -267,6 +267,9 @@ EXPORT_SYMBOL_GPL(sunxi_rsb_driver_register); > /* common code that starts a transfer */ > static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb) > { > + bool timeout; > + u32 status; > + > if (readl(rsb->regs + RSB_CTRL) & RSB_CTRL_START_TRANS) { > dev_dbg(rsb->dev, "RSB transfer still in progress\n"); > return -EBUSY; > @@ -279,8 +282,16 @@ static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb) > writel(RSB_CTRL_START_TRANS | RSB_CTRL_GLOBAL_INT_ENB, > rsb->regs + RSB_CTRL); > > - if (!wait_for_completion_io_timeout(&rsb->complete, > - msecs_to_jiffies(100))) { > + if (irqs_disabled()) { > + timeout = readl_poll_timeout_atomic(rsb->regs + RSB_INTS, > + status, status, 10, 100000); It would be good to check only for RSB_INTS_LOAD_BSY, RSB_INTS_TRANS_ERR and RSB_INTS_TRANS_OVER flags and clear them afterwards. That way we avoid problems if this path is used outside power off case. Best regards, Jernej > + } else { > + timeout = !wait_for_completion_io_timeout(&rsb- >complete, > + msecs_to_jiffies(100)); > + status = rsb->status; > + } > + > + if (timeout) { > dev_dbg(rsb->dev, "RSB timeout\n"); > > /* abort the transfer */ > @@ -292,18 +303,18 @@ static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb) > return -ETIMEDOUT; > } > > - if (rsb->status & RSB_INTS_LOAD_BSY) { > + if (status & RSB_INTS_LOAD_BSY) { > dev_dbg(rsb->dev, "RSB busy\n"); > return -EBUSY; > } > > - if (rsb->status & RSB_INTS_TRANS_ERR) { > - if (rsb->status & RSB_INTS_TRANS_ERR_ACK) { > + if (status & RSB_INTS_TRANS_ERR) { > + if (status & RSB_INTS_TRANS_ERR_ACK) { > dev_dbg(rsb->dev, "RSB slave nack\n"); > return -EINVAL; > } > > - if (rsb->status & RSB_INTS_TRANS_ERR_DATA) { > + if (status & RSB_INTS_TRANS_ERR_DATA) { > dev_dbg(rsb->dev, "RSB transfer data error\n"); > return -EIO; > } _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel