From patchwork Tue Oct 17 13:03:02 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Philipp Zabel X-Patchwork-Id: 10011935 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 23B61601E7 for ; Tue, 17 Oct 2017 13:04:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0D822288AE for ; Tue, 17 Oct 2017 13:04:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 02139288B0; Tue, 17 Oct 2017 13:04:58 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6B884288AE for ; Tue, 17 Oct 2017 13:04:58 +0000 (UTC) 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: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=giOVqmfUehNWz6c+339ly5lmRwpFpQ5WB7uL/gvYfJo=; b=kg0PvmpTwRDelf3GQI8ov9xErN peweQjhZPNP/fMlZW8fagVCukt7I/9edubWC6CO6fC2+K+pB18Pv+CJ5Uv8RVEUTn5yO5iRul9jrI MNmd5Wmn3BBBYauY9vlsrwiEzz5jjaksLxa777+yBAPwTnqCdgfj6MNNqsazHLFfXR2f61302UAWb yMQR9bxb9f/1iv+mvN1uIcdACAXcDJF5WXDiPixBOgxKoEhFgZkm8VSbpnj5EoS1tk5r8JVyIVT5W KfCT/5BzRvt0LdCY76zeU1iJxSCYVbx9Q7ve3OVaWkyuixNK9bA0xvOfNLzPfyT60Wybd2XjdxIvc 8NY2/TVA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1e4RYH-0008B2-Sj; Tue, 17 Oct 2017 13:04:57 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1e4RXF-0007Tg-NU for linux-arm-kernel@lists.infradead.org; Tue, 17 Oct 2017 13:03:58 +0000 Received: from lupine.hi.pengutronix.de ([2001:67c:670:100:3ad5:47ff:feaf:1a17] helo=lupine.pengutronix.de.) by metis.ext.pengutronix.de with esmtp (Exim 4.84_2) (envelope-from ) id 1e4RWj-0000Q7-4S; Tue, 17 Oct 2017 15:03:21 +0200 From: Philipp Zabel To: linux-kernel@vger.kernel.org Subject: [PATCH v4 1/5] reset: add reset-simple to unify socfpga, stm32, sunxi, and zx2967 Date: Tue, 17 Oct 2017 15:03:02 +0200 Message-Id: <20171017130306.881-2-p.zabel@pengutronix.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171017130306.881-1-p.zabel@pengutronix.de> References: <20171017130306.881-1-p.zabel@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:100:3ad5:47ff:feaf:1a17 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20171017_060354_046647_A0395083 X-CRM114-Status: GOOD ( 19.07 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kernel@pengutronix.de, Alexandru Gagniuc , Steffen Trumtrar , Alexandre Torgue , Andre Przywara , Dinh Nguyen , Chen-Yu Tsai , Maxime Coquelin , Philipp Zabel , Maxime Ripard , Baoyou Xie , Eugeniy Paltsev , =?UTF-8?q?Andreas=20F=C3=A4rber?= , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Copy reusable parts from the sunxi driver, to add a driver for simple reset controllers with reset lines that can be controlled by toggling bits in exclusive, contiguous register ranges using read-modify-write cycles under a spinlock. The following patches will replace compatible reset drivers with reset-simple, extending it where necessary. Signed-off-by: Philipp Zabel Reviewed-by: Alexandru Gagniuc Reviewed-by: Chen-Yu Tsai --- Changes since v3: - Split patch 1 into reset-simple and reset-sunxi parts. - Renamed reset_simple_set to reset_simple_update --- drivers/reset/Kconfig | 10 ++++ drivers/reset/Makefile | 1 + drivers/reset/reset-simple.c | 134 +++++++++++++++++++++++++++++++++++++++++++ drivers/reset/reset-simple.h | 41 +++++++++++++ 4 files changed, 186 insertions(+) create mode 100644 drivers/reset/reset-simple.c create mode 100644 drivers/reset/reset-simple.h diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index 1c88af2947245..392e65187cd5a 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -75,6 +75,16 @@ config RESET_PISTACHIO help This enables the reset driver for ImgTec Pistachio SoCs. +config RESET_SIMPLE + bool "Simple Reset Controller Driver" if COMPILE_TEST + default ARCH_SUNXI + help + This enables a simple reset controller driver for reset lines that + that can be asserted and deasserted by toggling bits in a contiguous, + exclusive register space. + + Currently this driver supports Allwinner SoCs. + config RESET_SOCFPGA bool "SoCFPGA Reset Driver" if COMPILE_TEST default ARCH_SOCFPGA || ARCH_STRATIX10 diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index af1c15c330b30..ddd3eeb193567 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_RESET_LPC18XX) += reset-lpc18xx.o obj-$(CONFIG_RESET_MESON) += reset-meson.o obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o +obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o obj-$(CONFIG_RESET_STM32) += reset-stm32.o obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o diff --git a/drivers/reset/reset-simple.c b/drivers/reset/reset-simple.c new file mode 100644 index 0000000000000..a5119457cec61 --- /dev/null +++ b/drivers/reset/reset-simple.c @@ -0,0 +1,134 @@ +/* + * Simple Reset Controller Driver + * + * Copyright (C) 2017 Pengutronix, Philipp Zabel + * + * Based on Allwinner SoCs Reset Controller driver + * + * Copyright 2013 Maxime Ripard + * + * Maxime Ripard + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "reset-simple.h" + +static inline struct reset_simple_data * +to_reset_simple_data(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct reset_simple_data, rcdev); +} + +static int reset_simple_update(struct reset_controller_dev *rcdev, + unsigned long id, bool assert) +{ + struct reset_simple_data *data = to_reset_simple_data(rcdev); + int reg_width = sizeof(u32); + int bank = id / (reg_width * BITS_PER_BYTE); + int offset = id % (reg_width * BITS_PER_BYTE); + unsigned long flags; + u32 reg; + + spin_lock_irqsave(&data->lock, flags); + + reg = readl(data->membase + (bank * reg_width)); + if (assert ^ data->active_low) + reg |= BIT(offset); + else + reg &= ~BIT(offset); + writel(reg, data->membase + (bank * reg_width)); + + spin_unlock_irqrestore(&data->lock, flags); + + return 0; +} + +static int reset_simple_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return reset_simple_update(rcdev, id, true); +} + +static int reset_simple_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return reset_simple_update(rcdev, id, false); +} + +const struct reset_control_ops reset_simple_ops = { + .assert = reset_simple_assert, + .deassert = reset_simple_deassert, +}; + +/** + * struct reset_simple_devdata - simple reset controller properties + * @active_low: if true, bits are cleared to assert the reset. Otherwise, bits + * are set to assert the reset. + */ +struct reset_simple_devdata { + bool active_low; +}; + +static const struct reset_simple_devdata reset_simple_active_low = { + .active_low = true, +}; + +static const struct of_device_id reset_simple_dt_ids[] = { + { .compatible = "allwinner,sun6i-a31-clock-reset", + .data = &reset_simple_active_low }, + { /* sentinel */ }, +}; + +static int reset_simple_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct reset_simple_devdata *devdata; + struct reset_simple_data *data; + void __iomem *membase; + struct resource *res; + + devdata = of_device_get_match_data(dev); + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + membase = devm_ioremap_resource(dev, res); + if (IS_ERR(membase)) + return PTR_ERR(membase); + + spin_lock_init(&data->lock); + data->membase = membase; + data->rcdev.owner = THIS_MODULE; + data->rcdev.nr_resets = resource_size(res) * BITS_PER_BYTE; + data->rcdev.ops = &reset_simple_ops; + data->rcdev.of_node = dev->of_node; + + if (devdata) + data->active_low = devdata->active_low; + + return devm_reset_controller_register(dev, &data->rcdev); +} + +static struct platform_driver reset_simple_driver = { + .probe = reset_simple_probe, + .driver = { + .name = "simple-reset", + .of_match_table = reset_simple_dt_ids, + }, +}; +builtin_platform_driver(reset_simple_driver); diff --git a/drivers/reset/reset-simple.h b/drivers/reset/reset-simple.h new file mode 100644 index 0000000000000..39af2014b5f12 --- /dev/null +++ b/drivers/reset/reset-simple.h @@ -0,0 +1,41 @@ +/* + * Simple Reset Controller ops + * + * Based on Allwinner SoCs Reset Controller driver + * + * Copyright 2013 Maxime Ripard + * + * Maxime Ripard + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#ifndef __RESET_SIMPLE_H__ +#define __RESET_SIMPLE_H__ + +#include +#include +#include + +/** + * struct reset_simple_data - driver data for simple reset controllers + * @lock: spinlock to protect registers during read-modify-write cycles + * @membase: memory mapped I/O register range + * @rcdev: reset controller device base structure + * @active_low: if true, bits are cleared to assert the reset. Otherwise, bits + * are set to assert the reset. Note that this says nothing about + * the voltage level of the actual reset line. + */ +struct reset_simple_data { + spinlock_t lock; + void __iomem *membase; + struct reset_controller_dev rcdev; + bool active_low; +}; + +extern const struct reset_control_ops reset_simple_ops; + +#endif /* __RESET_SIMPLE_H__ */