From patchwork Tue Jun 20 06:26:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 13285206 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 8A924EB64D7 for ; Tue, 20 Jun 2023 06:27:30 +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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version: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=ZQlWN4r5VvFiDIm+xCXl9f6AyXd5ZbW2xgRT0eHjD7c=; b=RFFj9u46Lo9rp4 Ak6TQneoyw7mbISrBmY7NXYnqGx2Vwja6A68om0D8cvu2MRBRukcVRlu1jomChRnR3j72BmR9K7aG 4u3eSuQpYHlnJATzuhxDLrer1Sg4A/nzBwss3h9egbnDg/JPnOXDT8fuiOUI5g7JmZgDtaL84F+Z3 WykW2Kdh0tbIdd6U+1yxZfPRU6qp1y/WpvsFJbi+RFxkKpEZqhpnJSO7y0x7ZRiobOC/kBU9tf0od f5h8z+XZP8oN82fvd1zA5ziQvVlMWbcVmA6ve+KVRYdLuAjaw7an7Vk08oGFRj4XJ1YY4Q2s7ucWy dM3SN8M7LNoNyFxwyBkA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qBUpa-00AH4j-0a; Tue, 20 Jun 2023 06:27:10 +0000 Received: from relay2-d.mail.gandi.net ([2001:4b98:dc4:8::222]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qBUpW-00AH3y-0w for linux-arm-kernel@lists.infradead.org; Tue, 20 Jun 2023 06:27:08 +0000 X-GND-Sasl: miquel.raynal@bootlin.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1687242419; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=7pl6qCNBQeotbXsdQRYataHay2+MrATT6vr5AKa1Xc8=; b=n0DLBu/0zLrq8qT4ZF0wn6HAIyqtn4wQMCPiYIDg+qNZcEkLArU7QPCOWAcUrxng5u+k8e 0DsaH6TPnKLn9WqeNxmG+UEBNsID/fpHmRgGX1fdPX2n2PzXTs+C9l3BiZs5b5tifWyv9i KYyFVqVMNd2GLPWMB3BW+3swrHAnx/3eWdst7C5nFZnAsGag6bpLDXVAd80W3Z/GO6zVqj gWOIvkxXdvUWpczm0oo3epTKFCWpnXk18lJ+nDx/q+FTZCSXMsyIO4E9zxJB4KdsP5t11J qZip9iV/yQ/NkOiPNCZlWXcsyn/HnQDiW+MPEvpmKnFVRjQoOwBqAzEsvUAQsg== X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com Received: by mail.gandi.net (Postfix) with ESMTPSA id 6FD6D40007; Tue, 20 Jun 2023 06:26:58 +0000 (UTC) From: Miquel Raynal To: Sebastian Reichel Subject: [PATCH v4] power: reset: at91-reset: add sysfs interface to the power on reason Date: Tue, 20 Jun 2023 08:26:57 +0200 Message-Id: <20230620062657.3127468-1-miquel.raynal@bootlin.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230619_232706_658179_FAF0BA2B X-CRM114-Status: GOOD ( 20.01 ) 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: , Cc: Kamel Bouhara , Alexandre Belloni , linux-pm@vger.kernel.org, Thomas Petazzoni , Miquel Raynal , Claudiu Beznea , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Kamel Bouhara Introduce a list of generic reset sources and use them to export the power on reason through sysfs. Update the ABI documentation to describe this new interface. Signed-off-by: Kamel Bouhara Acked-by: Nicolas Ferre [Miquel Raynal: Follow-up on Kamel's work, 4 years later] Signed-off-by: Miquel Raynal --- Changes in v4: * Patch 1/2 was merged. * Changed the "low-power condition" into a "brown-out reset" as suggested by Sebastian. Changes in v3: * Made the series bisectable. * Updated the date and kernel version for this new feature. * Changed a few definitions as discussed with Sebastian. Changes in v2: * Collected Nicolas' Acked-by * Dropped the Xtal frequency information (as this may change between platforms of course). .../testing/sysfs-platform-power-on-reason | 12 ++++++ drivers/power/reset/at91-reset.c | 37 ++++++++++++++----- include/linux/power/power_on_reason.h | 19 ++++++++++ 3 files changed, 58 insertions(+), 10 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-platform-power-on-reason create mode 100644 include/linux/power/power_on_reason.h diff --git a/Documentation/ABI/testing/sysfs-platform-power-on-reason b/Documentation/ABI/testing/sysfs-platform-power-on-reason new file mode 100644 index 000000000000..c3b29dbc64bf --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform-power-on-reason @@ -0,0 +1,12 @@ +What: /sys/devices/platform/.../power_on_reason +Date: June 2023 +KernelVersion: 6.5 +Contact: Kamel Bouhara +Description: Shows system power on reason. The following strings/reasons can + be read (the list can be extended): + "regular power-up", "RTC wakeup", "watchdog timeout", + "software reset", "reset button action", "CPU clock failure", + "crystal oscillator failure", "brown-out reset", + "unknown reason". + + The file is read only. diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c index d6884841a6dc..aa9b012d3d00 100644 --- a/drivers/power/reset/at91-reset.c +++ b/drivers/power/reset/at91-reset.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -149,44 +150,54 @@ static int at91_reset(struct notifier_block *this, unsigned long mode, return NOTIFY_DONE; } -static const char * __init at91_reset_reason(struct at91_reset *reset) +static const char *at91_reset_reason(struct at91_reset *reset) { u32 reg = readl(reset->rstc_base + AT91_RSTC_SR); const char *reason; switch ((reg & AT91_RSTC_RSTTYP) >> 8) { case RESET_TYPE_GENERAL: - reason = "general reset"; + reason = POWER_ON_REASON_REGULAR; break; case RESET_TYPE_WAKEUP: - reason = "wakeup"; + reason = POWER_ON_REASON_RTC; break; case RESET_TYPE_WATCHDOG: - reason = "watchdog reset"; + reason = POWER_ON_REASON_WATCHDOG; break; case RESET_TYPE_SOFTWARE: - reason = "software reset"; + reason = POWER_ON_REASON_SOFTWARE; break; case RESET_TYPE_USER: - reason = "user reset"; + reason = POWER_ON_REASON_RST_BTN; break; case RESET_TYPE_CPU_FAIL: - reason = "CPU clock failure detection"; + reason = POWER_ON_REASON_CPU_CLK_FAIL; break; case RESET_TYPE_XTAL_FAIL: - reason = "32.768 kHz crystal failure detection"; + reason = POWER_ON_REASON_XTAL_FAIL; break; case RESET_TYPE_ULP2: - reason = "ULP2 reset"; + reason = POWER_ON_REASON_BROWN_OUT; break; default: - reason = "unknown reset"; + reason = POWER_ON_REASON_UNKNOWN; break; } return reason; } +static ssize_t power_on_reason_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct platform_device *pdev = to_platform_device(dev); + struct at91_reset *reset = platform_get_drvdata(pdev); + + return sprintf(buf, "%s\n", at91_reset_reason(reset)); +} +static DEVICE_ATTR_RO(power_on_reason); + static const struct of_device_id at91_ramc_of_match[] = { { .compatible = "atmel,at91sam9260-sdramc", @@ -391,6 +402,12 @@ static int __init at91_reset_probe(struct platform_device *pdev) if (ret) goto disable_clk; + ret = device_create_file(&pdev->dev, &dev_attr_power_on_reason); + if (ret) { + dev_err(&pdev->dev, "Could not create sysfs entry\n"); + return ret; + } + dev_info(&pdev->dev, "Starting after %s\n", at91_reset_reason(reset)); return 0; diff --git a/include/linux/power/power_on_reason.h b/include/linux/power/power_on_reason.h new file mode 100644 index 000000000000..95a1ec0c403c --- /dev/null +++ b/include/linux/power/power_on_reason.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Author: Kamel Bouhra + */ + +#ifndef POWER_ON_REASON_H +#define POWER_ON_REASON_H + +#define POWER_ON_REASON_REGULAR "regular power-up" +#define POWER_ON_REASON_RTC "RTC wakeup" +#define POWER_ON_REASON_WATCHDOG "watchdog timeout" +#define POWER_ON_REASON_SOFTWARE "software reset" +#define POWER_ON_REASON_RST_BTN "reset button action" +#define POWER_ON_REASON_CPU_CLK_FAIL "CPU clock failure" +#define POWER_ON_REASON_XTAL_FAIL "crystal oscillator failure" +#define POWER_ON_REASON_BROWN_OUT "brown-out reset" +#define POWER_ON_REASON_UNKNOWN "unknown reason" + +#endif /* POWER_ON_REASON_H */