From patchwork Tue Jun 9 17:49:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 11596355 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 934391392 for ; Tue, 9 Jun 2020 17:55:22 +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 5689920734 for ; Tue, 9 Jun 2020 17:55:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="IH+rnw4A" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5689920734 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de 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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: 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: List-Owner; bh=3H5fC/V4IgB9C3jR2pbzzH2CBji614nqHOAvUVM0GM0=; b=IH+rnw4A3tkUjM 3MuoHPut4HHzB4NkJqA3aRtnWskipVU6APHc2VSkOVcXxBA5JjkJGFxHbn8GOD6eIRJTCPDzav8yF 5ndJ479RfWN7GONflf3aWH9JJnJTJNhwNoXnH9ZtYdM4B4ZhmgdqO0rTcVwUqIEpYanCpxRNMTABC +YulcE/pLVpdCFiqj6t/vkU0gtRXLe8PK8dySYSU3XueEPwGbscRH+vHFTbdUjQ3NJIOHrGVOZhV4 8DMKTC2IdI9Ala/1fjoW3jumjHYvYlCGN1Aj4yXlb9xQMT2lBcGH84q3nryJzrDxoJ5Q6rGy9p8nr Zsom2syk1STVkoP1nA0A==; 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 1jiiT1-00080l-Lb; Tue, 09 Jun 2020 17:55:19 +0000 Received: from mx2.suse.de ([195.135.220.15]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jiiOC-0001aK-Uj; Tue, 09 Jun 2020 17:50:27 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 8481BB17C; Tue, 9 Jun 2020 17:50:22 +0000 (UTC) From: Nicolas Saenz Julienne To: f.fainelli@gmail.com, gregkh@linuxfoundation.org, wahrenst@gmx.net, p.zabel@pengutronix.de, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/9] reset: Add Raspberry Pi 4 firmware reset controller Date: Tue, 9 Jun 2020 19:49:55 +0200 Message-Id: <20200609175003.19793-3-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200609175003.19793-1-nsaenzjulienne@suse.de> References: <20200609175003.19793-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200609_105022_735008_C9D9B7FE X-CRM114-Status: GOOD ( 18.06 ) 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 [195.135.220.15 listed in list.dnswl.org] 0.0 RCVD_IN_MSPIKE_H3 RBL: Good reputation (+3) [195.135.220.15 listed in wl.mailspike.net] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record 0.0 RCVD_IN_MSPIKE_WL Mailspike good senders 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: tim.gover@raspberrypi.org, mathias.nyman@linux.intel.com, linux-pci@vger.kernel.org, linux-usb@vger.kernel.org, Nicolas Saenz Julienne , andy.shevchenko@gmail.com, lorenzo.pieralisi@arm.com, bcm-kernel-feedback-list@broadcom.com, linux-rpi-kernel@lists.infradead.org, helgaas@kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Raspberry Pi 4's co-processor controls some of the board's HW initialization process, but it's up to Linux to trigger it when relevant. Introduce a reset controller capable of interfacing with RPi4's co-processor that models these firmware initialization routines as reset lines. Signed-off-by: Nicolas Saenz Julienne Reviewed-by: Florian Fainelli --- Changes since v1: - Make the whole driver less USB centric as per Florian's comments drivers/reset/Kconfig | 11 +++ drivers/reset/Makefile | 1 + drivers/reset/reset-raspberrypi.c | 126 ++++++++++++++++++++++++++++++ 3 files changed, 138 insertions(+) create mode 100644 drivers/reset/reset-raspberrypi.c diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index d9efbfd29646..97e848740e13 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -140,6 +140,17 @@ config RESET_QCOM_PDC to control reset signals provided by PDC for Modem, Compute, Display, GPU, Debug, AOP, Sensors, Audio, SP and APPS. +config RESET_RASPBERRYPI + tristate "Raspberry Pi 4 Firmware Reset Driver" + depends on RASPBERRYPI_FIRMWARE || (RASPBERRYPI_FIRMWARE=n && COMPILE_TEST) + default USB_XHCI_PCI + help + Raspberry Pi 4's co-processor controls some of the board's HW + initialization process, but it's up to Linux to trigger it when + relevant. This driver provides a reset controller capable of + interfacing with RPi4's co-processor and model these firmware + initialization routines as reset lines. + config RESET_SCMI tristate "Reset driver controlled via ARM SCMI interface" depends on ARM_SCMI_PROTOCOL || COMPILE_TEST diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index 249ed357c997..16947610cc3b 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o obj-$(CONFIG_RESET_QCOM_AOSS) += reset-qcom-aoss.o obj-$(CONFIG_RESET_QCOM_PDC) += reset-qcom-pdc.o +obj-$(CONFIG_RESET_RASPBERRYPI) += reset-raspberrypi.o obj-$(CONFIG_RESET_SCMI) += reset-scmi.o obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o obj-$(CONFIG_RESET_STM32MP157) += reset-stm32mp1.o diff --git a/drivers/reset/reset-raspberrypi.c b/drivers/reset/reset-raspberrypi.c new file mode 100644 index 000000000000..5fc8c6319a20 --- /dev/null +++ b/drivers/reset/reset-raspberrypi.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Raspberry Pi 4 firmware reset driver + * + * Copyright (C) 2020 Nicolas Saenz Julienne + */ +#include +#include +#include +#include +#include +#include +#include + +struct rpi_reset { + struct reset_controller_dev rcdev; + struct rpi_firmware *fw; +}; + +enum rpi_reset_ids { + RASPBERRYPI_FIRMWARE_RESET_ID_USB, + RASPBERRYPI_FIRMWARE_RESET_NUM_IDS +}; + +static inline struct rpi_reset *to_rpi(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct rpi_reset, rcdev); +} + +static int rpi_reset_reset(struct reset_controller_dev *rcdev, unsigned long id) +{ + struct rpi_reset *priv = to_rpi(rcdev); + u32 dev_addr; + int ret; + + switch (id) { + case RASPBERRYPI_FIRMWARE_RESET_ID_USB: + /* + * The Raspberry Pi 4 gets its USB functionality from VL805, a + * PCIe chip that implements xHCI. After a PCI reset, VL805's + * firmware may either be loaded directly from an EEPROM or, if + * not present, by the SoC's co-processor, VideoCore. rpi's + * VideoCore OS contains both the non public firmware load + * logic and the VL805 firmware blob. This triggers the + * aforementioned process. + * + * The pci device address is expected is expected by the + * firmware encoded like this: + * + * PCI_BUS << 20 | PCI_SLOT << 15 | PCI_FUNC << 12 + * + * But since rpi's PCIe is hardwired, we know the address in + * advance. + */ + dev_addr = 0x100000; + ret = rpi_firmware_property(priv->fw, RPI_FIRMWARE_NOTIFY_XHCI_RESET, + &dev_addr, sizeof(dev_addr)); + if (ret) + return ret; + + /* Wait for vl805 to startup */ + usleep_range(200, 1000); + break; + + default: + return -EINVAL; + } + + return 0; +} + +static const struct reset_control_ops rpi_reset_ops = { + .reset = rpi_reset_reset, +}; + +static int rpi_reset_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *fw_node; + struct rpi_firmware *fw; + struct rpi_reset *priv; + + fw_node = of_get_parent(dev->of_node); + if (!fw_node) { + dev_err(dev, "Missing firmware node\n"); + return -ENOENT; + } + + fw = rpi_firmware_get(fw_node); + of_node_put(fw_node); + if (!fw) + return -EPROBE_DEFER; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + dev_set_drvdata(dev, priv); + + priv->fw = fw; + priv->rcdev.owner = THIS_MODULE; + priv->rcdev.nr_resets = RASPBERRYPI_FIRMWARE_RESET_NUM_IDS; + priv->rcdev.ops = &rpi_reset_ops; + priv->rcdev.of_node = dev->of_node; + + return devm_reset_controller_register(dev, &priv->rcdev); +} + +static const struct of_device_id rpi_reset_of_match[] = { + { .compatible = "raspberrypi,firmware-reset" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rpi_reset_of_match); + +static struct platform_driver rpi_reset_driver = { + .probe = rpi_reset_probe, + .driver = { + .name = "raspberrypi-reset", + .of_match_table = rpi_reset_of_match, + }, +}; +module_platform_driver(rpi_reset_driver); + +MODULE_AUTHOR("Nicolas Saenz Julienne "); +MODULE_DESCRIPTION("Raspberry Pi 4 firmware reset driver"); +MODULE_LICENSE("GPL");