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 B698AC55160 for ; Thu, 30 Jul 2026 11:00:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=PfAsvFSHoEZl41kC0RBm8RRb80pooqjoeOLDPddYCF8=; b=azJmBDaa90d2u0Tf8+2R5HH4Q3 TgrNTZlbNpWelb7PJlVTYvd5r9Wd0HZs64x7tnKQy9g5y8sqvd6p87XU5xLho/C6C06sT4oBGHtvH r670UQM7py9cq4ahI+RSiV1VuCcMJC0qz08RTidHZU4ArkjgX/sNOwJq/8fu/BPUC3jhDy/hExKn5 PapxbkeZzsKACzl0z5Mw/VSZHuYIJg93jeZYlCn50Q8O/m55QFslEseu2HPGI71OmarH9K/oV2jiG x/SoLAYwMK2YSEyRQOFxAv76wuBWSkyTYIp4S6BAuNr4YWlxRQnG3uLod7CRi5NWP78uoTUd5Puy0 SdZZaNgA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wpOUs-0000000AIFN-3fBW; Thu, 30 Jul 2026 11:00:18 +0000 Received: from galois.linutronix.de ([193.142.43.55]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wpOUI-0000000AHxU-2PJk; Thu, 30 Jul 2026 10:59:46 +0000 From: Gregor Herburger DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1785409178; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PfAsvFSHoEZl41kC0RBm8RRb80pooqjoeOLDPddYCF8=; b=veiNp7hm91R3TfuTtG1wDsWGoZjdMhL9i0sGRliTom7W68YQt1FxUt4r33vq0ozUw8Immz SV6CCPW+knlK6uVtr9GvpLocKuNG0w7B64Aec2t/broSmjHhO99WMKoQ5vs36DcE7IY4Hu WkKCzZr8RS7rvfr9H+f8okJjUTXsG43b8VAT8T38Z8IRVWdfMt3CHH9XNexW7TLMcXW8Re dKSA2lU2aWa+DT9fF5M/SLa88kUzogqs2YSSnY9iaTTL4dHZG+XHvgWfaIyM6+1HndpXrN YgQa47ZF9+Yl0081dH/gUYAzA6FVNuiVIZl82is2LfJn1K9ezsNY8OCpi6kOgQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1785409178; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PfAsvFSHoEZl41kC0RBm8RRb80pooqjoeOLDPddYCF8=; b=jlUSmhe8YyczNEgZZCH9PzhIpm4RrHG6z4RNx0GD2CUSiC3QY74H90qVCdmIR16dPxvzyt Ue/1vxwC9iV4d2BA== Date: Thu, 30 Jul 2026 12:59:32 +0200 Subject: [PATCH RESEND v3 3/4] firmware: raspberrypi: Add reboot mode support MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260730-rpi-tryboot-v3-3-849c001d67f8@linutronix.de> References: <20260730-rpi-tryboot-v3-0-849c001d67f8@linutronix.de> In-Reply-To: <20260730-rpi-tryboot-v3-0-849c001d67f8@linutronix.de> To: Florian Fainelli , Broadcom internal kernel review list , Ray Jui , Scott Branden , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Eric Anholt , Stefan Wahren Cc: linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Gregor Herburger X-Developer-Signature: v=1; a=ed25519-sha256; t=1785409177; l=5561; i=gregor.herburger@linutronix.de; s=20260226; h=from:subject:message-id; bh=qxy/1mTBz6j5Alv1f+kWCyPU7w4JnM/MdXtLxrkOFtc=; b=A/R16qMElZO/axcdMnDhvU2BPFJGdg5ZUXNLpa+HybXnNvbPqGlMxiQ4H39oRF3mUFbhDIWgF EcKKcZK2tXuCJNoJgK/n3rY5JFz3rEnHxw8x3Kl6sXtFytfdm5ohUv3 X-Developer-Key: i=gregor.herburger@linutronix.de; a=ed25519; pk=u72Lv7+/lS5CC1hmSrb17lv/6CK7HBh4Lvz77PHA5LM= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260730_035942_773770_A75179D4 X-CRM114-Status: GOOD ( 20.22 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The Raspberry Pi firmware has a tryboot mode where it tries to boot from another partition. This can be used to create a A/B update scheme. To enable this on the next boot, the RPI_FIRMWARE_SET_REBOOT_FLAGS message must be sent to the firmware. Add support for this by registering a reboot mode driver. Furthermore, safely registering the reboot mode requires adjusting the teardown sequence. Replace the manually called rpi_firmware_put() with a devres-managed called (devm_add_action_or_reset). Without this, the cleanup function of devm_reboot_mode_register() would trigger a use-after-free error by attempting to access the firmware context after it had already been freed by rpi_firmware_remove(). Signed-off-by: Gregor Herburger --- drivers/firmware/Kconfig | 2 ++ drivers/firmware/raspberrypi.c | 40 ++++++++++++++++++++++++++---- include/soc/bcm2835/raspberrypi-firmware.h | 2 ++ 3 files changed, 39 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index bbd2155d8483..34605bf7c973 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -115,6 +115,8 @@ config ISCSI_IBFT config RASPBERRYPI_FIRMWARE tristate "Raspberry Pi Firmware Driver" depends on BCM2835_MBOX + select POWER_RESET + select REBOOT_MODE help This option enables support for communicating with the firmware on the Raspberry Pi. diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c index 0aa322e9a2e7..2a0c40b8052e 100644 --- a/drivers/firmware/raspberrypi.c +++ b/drivers/firmware/raspberrypi.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -29,6 +30,7 @@ struct rpi_firmware { struct mbox_client cl; struct mbox_chan *chan; /* The property channel. */ struct completion c; + struct reboot_mode_driver reboot_mode; u32 enabled; struct kref consumers; @@ -273,10 +275,37 @@ static void devm_rpi_firmware_put(void *data) rpi_firmware_put(fw); } +static int rpi_firmware_reboot_mode_write(struct reboot_mode_driver *reboot, + unsigned int magic) +{ + struct rpi_firmware *fw = container_of(reboot, struct rpi_firmware, + reboot_mode); + __le32 fw_magic = cpu_to_le32(magic); + + if (!magic) + return 0; + + return rpi_firmware_property(fw, RPI_FIRMWARE_SET_REBOOT_FLAGS, + &fw_magic, sizeof(fw_magic)); +} + +static void rpi_register_reboot_mode(struct device *dev, struct rpi_firmware *fw) +{ + int ret; + + fw->reboot_mode.dev = dev; + fw->reboot_mode.write = rpi_firmware_reboot_mode_write; + ret = devm_reboot_mode_register(dev, &fw->reboot_mode); + if (ret) + dev_err(dev, "Failed to register reboot mode: %d\n", ret); + +} + static int rpi_firmware_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct rpi_firmware *fw; + int ret; /* * Memory will be freed by rpi_firmware_delete() once all users have @@ -292,7 +321,7 @@ static int rpi_firmware_probe(struct platform_device *pdev) fw->chan = mbox_request_channel(&fw->cl, 0); if (IS_ERR(fw->chan)) { - int ret = PTR_ERR(fw->chan); + ret = PTR_ERR(fw->chan); kfree(fw); return dev_err_probe(dev, ret, "Failed to get mbox channel\n"); } @@ -302,9 +331,14 @@ static int rpi_firmware_probe(struct platform_device *pdev) platform_set_drvdata(pdev, fw); + ret = devm_add_action_or_reset(dev, devm_rpi_firmware_put, fw); + if (ret) + return ret; + rpi_firmware_print_firmware_revision(fw); rpi_register_hwmon_driver(dev, fw); rpi_register_clk_driver(dev); + rpi_register_reboot_mode(dev, fw); return 0; } @@ -321,14 +355,10 @@ static void rpi_firmware_shutdown(struct platform_device *pdev) static void rpi_firmware_remove(struct platform_device *pdev) { - struct rpi_firmware *fw = platform_get_drvdata(pdev); - platform_device_unregister(rpi_hwmon); rpi_hwmon = NULL; platform_device_unregister(rpi_clk); rpi_clk = NULL; - - rpi_firmware_put(fw); } static const struct of_device_id rpi_firmware_of_match[] = { diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h index 66cc5a426c3c..f905bff0fb3e 100644 --- a/include/soc/bcm2835/raspberrypi-firmware.h +++ b/include/soc/bcm2835/raspberrypi-firmware.h @@ -81,6 +81,7 @@ enum rpi_firmware_property_tag { RPI_FIRMWARE_GET_POE_HAT_VAL = 0x00030049, RPI_FIRMWARE_SET_POE_HAT_VAL = 0x00030050, RPI_FIRMWARE_NOTIFY_XHCI_RESET = 0x00030058, + RPI_FIRMWARE_GET_REBOOT_FLAGS = 0x00030064, RPI_FIRMWARE_NOTIFY_DISPLAY_DONE = 0x00030066, RPI_FIRMWARE_SET_CLOCK_STATE = 0x00038001, RPI_FIRMWARE_SET_CLOCK_RATE = 0x00038002, @@ -92,6 +93,7 @@ enum rpi_firmware_property_tag { RPI_FIRMWARE_SET_SDHOST_CLOCK = 0x00038042, RPI_FIRMWARE_SET_GPIO_CONFIG = 0x00038043, RPI_FIRMWARE_SET_PERIPH_REG = 0x00038045, + RPI_FIRMWARE_SET_REBOOT_FLAGS = 0x00038064, /* Dispmanx TAGS */ RPI_FIRMWARE_FRAMEBUFFER_ALLOCATE = 0x00040001, -- 2.47.3