Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752266AbdHPJr0 (ORCPT ); Wed, 16 Aug 2017 05:47:26 -0400 Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:42077 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752029AbdHPJrY (ORCPT ); Wed, 16 Aug 2017 05:47:24 -0400 From: Philipp Zabel To: linux-kernel@vger.kernel.org Cc: Alexandru Gagniuc , Andre Przywara , Maxime Coquelin , Alexandre Torgue , Maxime Ripard , Chen-Yu Tsai , Baoyou Xie , Eugeniy Paltsev , Steffen Trumtrar , Dinh Nguyen , =?UTF-8?q?Andreas=20F=C3=A4rber?= , linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de, Philipp Zabel Subject: [PATCH v3 1/5] reset: add reset-simple to unify socfpga, stm32, sunxi, and zx2967 Date: Wed, 16 Aug 2017 11:46:57 +0200 Message-Id: <20170816094701.30678-2-p.zabel@pengutronix.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170816094701.30678-1-p.zabel@pengutronix.de> References: <20170816094701.30678-1-p.zabel@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 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-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12032 Lines: 394 Split reusable parts out of 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 separate sunxi driver still remains to register the early reset controllers, but it reuses the reset-simple ops. The following patches will replace compatible reset drivers with reset-simple, extending it where necessary. Signed-off-by: Philipp Zabel --- Changes since v2: - Add kerneldoc comment for struct reset_simple_devdata and struct reset_simple_data. - Rename "inverted" properties to "active_low". - Use of_device_get_match_data instead of of_match_device. --- drivers/reset/Kconfig | 11 ++++ drivers/reset/Makefile | 1 + drivers/reset/reset-simple.c | 134 +++++++++++++++++++++++++++++++++++++++++++ drivers/reset/reset-simple.h | 41 +++++++++++++ drivers/reset/reset-sunxi.c | 104 ++------------------------------- 5 files changed, 193 insertions(+), 98 deletions(-) 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 52d5251660b9b..f7ba01a71daee 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -68,6 +68,16 @@ 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 @@ -83,6 +93,7 @@ config RESET_STM32 config RESET_SUNXI bool "Allwinner SoCs Reset Driver" if COMPILE_TEST && !ARCH_SUNXI default ARCH_SUNXI + select RESET_SIMPLE help This enables the reset driver for Allwinner SoCs. diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index b62783f50fe5b..ab4af99c3dfdc 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -11,6 +11,7 @@ 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..70c57c0758c39 --- /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_set(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_set(rcdev, id, true); +} + +static int reset_simple_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return reset_simple_set(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__ */ diff --git a/drivers/reset/reset-sunxi.c b/drivers/reset/reset-sunxi.c index 2c7dd1fd08df6..db9a1a75523f4 100644 --- a/drivers/reset/reset-sunxi.c +++ b/drivers/reset/reset-sunxi.c @@ -22,64 +22,11 @@ #include #include -struct sunxi_reset_data { - spinlock_t lock; - void __iomem *membase; - struct reset_controller_dev rcdev; -}; - -static int sunxi_reset_assert(struct reset_controller_dev *rcdev, - unsigned long id) -{ - struct sunxi_reset_data *data = container_of(rcdev, - struct sunxi_reset_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)); - writel(reg & ~BIT(offset), data->membase + (bank * reg_width)); - - spin_unlock_irqrestore(&data->lock, flags); - - return 0; -} - -static int sunxi_reset_deassert(struct reset_controller_dev *rcdev, - unsigned long id) -{ - struct sunxi_reset_data *data = container_of(rcdev, - struct sunxi_reset_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)); - writel(reg | BIT(offset), data->membase + (bank * reg_width)); - - spin_unlock_irqrestore(&data->lock, flags); - - return 0; -} - -static const struct reset_control_ops sunxi_reset_ops = { - .assert = sunxi_reset_assert, - .deassert = sunxi_reset_deassert, -}; +#include "reset-simple.h" static int sunxi_reset_init(struct device_node *np) { - struct sunxi_reset_data *data; + struct reset_simple_data *data; struct resource res; resource_size_t size; int ret; @@ -108,8 +55,9 @@ static int sunxi_reset_init(struct device_node *np) data->rcdev.owner = THIS_MODULE; data->rcdev.nr_resets = size * 8; - data->rcdev.ops = &sunxi_reset_ops; + data->rcdev.ops = &reset_simple_ops; data->rcdev.of_node = np; + data->active_low = true; return reset_controller_register(&data->rcdev); @@ -122,6 +70,8 @@ static int sunxi_reset_init(struct device_node *np) * These are the reset controller we need to initialize early on in * our system, before we can even think of using a regular device * driver for it. + * The controllers that we can register through the regular device + * model are handled by the simple reset driver directly. */ static const struct of_device_id sunxi_early_reset_dt_ids[] __initconst = { { .compatible = "allwinner,sun6i-a31-ahb1-reset", }, @@ -135,45 +85,3 @@ void __init sun6i_reset_init(void) for_each_matching_node(np, sunxi_early_reset_dt_ids) sunxi_reset_init(np); } - -/* - * And these are the controllers we can register through the regular - * device model. - */ -static const struct of_device_id sunxi_reset_dt_ids[] = { - { .compatible = "allwinner,sun6i-a31-clock-reset", }, - { /* sentinel */ }, -}; - -static int sunxi_reset_probe(struct platform_device *pdev) -{ - struct sunxi_reset_data *data; - struct resource *res; - - data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); - if (!data) - return -ENOMEM; - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - data->membase = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(data->membase)) - return PTR_ERR(data->membase); - - spin_lock_init(&data->lock); - - data->rcdev.owner = THIS_MODULE; - data->rcdev.nr_resets = resource_size(res) * 8; - data->rcdev.ops = &sunxi_reset_ops; - data->rcdev.of_node = pdev->dev.of_node; - - return devm_reset_controller_register(&pdev->dev, &data->rcdev); -} - -static struct platform_driver sunxi_reset_driver = { - .probe = sunxi_reset_probe, - .driver = { - .name = "sunxi-reset", - .of_match_table = sunxi_reset_dt_ids, - }, -}; -builtin_platform_driver(sunxi_reset_driver); -- 2.11.0