lkml.org 
[lkml]   [2017]   [Mar]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 1/2] reset: add reset-simple to unify socfpga, stm32, and sunxi
From
Date
Hi Philipp,

On 03/08/2017 11:19 AM, Andre Przywara wrote:
> Hi,
>
> On 08/03/17 09:54, Philipp Zabel wrote:
>> Reset operations for simple reset controllers with reset lines that can
>> be controlled by toggling bits in (mostly) contiguous register ranges
>> using read-modify-write cycles under a spinlock. So far this covers the
>> socfpga, stm32, and sunxi drivers.
>
> Wow, that looks nice, thanks for that.
>
> But can't we go one step further and unify those driver into one file then?
> And either have different probe functions to cover the different DT
> requirements or to just have one unified probe checking for the super
> set of all properties?

I agree with Andre. It looks nice and it should be a good thing to have
a common probe inside reset-simple.c
Maybe only "nresets" and "inverted" DT properties are needed.

Regards

Alex



>
> Also ....
>
>>
>> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
>> ---
>> drivers/reset/Kconfig | 6 +++
>> drivers/reset/Makefile | 1 +
>> drivers/reset/reset-simple.c | 92 +++++++++++++++++++++++++++++++++++++++++
>> drivers/reset/reset-simple.h | 53 ++++++++++++++++++++++++
>> drivers/reset/reset-socfpga.c | 96 +++++--------------------------------------
>> drivers/reset/reset-stm32.c | 73 ++++----------------------------
>> drivers/reset/reset-sunxi.c | 82 +++++-------------------------------
>> 7 files changed, 181 insertions(+), 222 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 d21c07ccc94e5..d968becd0474c 100644
>> --- a/drivers/reset/Kconfig
>> +++ b/drivers/reset/Kconfig
>> @@ -62,21 +62,27 @@ config RESET_PISTACHIO
>> help
>> This enables the reset driver for ImgTec Pistachio SoCs.
>>
>> +config RESET_SIMPLE
>> + bool
>> +
>> config RESET_SOCFPGA
>> bool "SoCFPGA Reset Driver" if COMPILE_TEST
>> default ARCH_SOCFPGA
>> + select RESET_SIMPLE
>> help
>> This enables the reset controller driver for Altera SoCFPGAs.
>>
>> config RESET_STM32
>> bool "STM32 Reset Driver" if COMPILE_TEST
>> default ARCH_STM32
>> + select RESET_SIMPLE
>> help
>> This enables the RCC reset controller driver for STM32 MCUs.
>>
>> 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 02a74db943397..f5cc015f20956 100644
>> --- a/drivers/reset/Makefile
>> +++ b/drivers/reset/Makefile
>> @@ -10,6 +10,7 @@ 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..2160e84fe216b
>> --- /dev/null
>> +++ b/drivers/reset/reset-simple.c
>> @@ -0,0 +1,92 @@
>> +/*
>> + * Simple Reset Controller ops
>> + *
>> + * Based on Allwinner SoCs Reset Controller driver
>> + *
>> + * Copyright 2013 Maxime Ripard
>> + *
>> + * Maxime Ripard <maxime.ripard@free-electrons.com>
>> + *
>> + * 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 <linux/io.h>
>> +#include <linux/device.h>
>> +#include <linux/reset-controller.h>
>> +#include <linux/spinlock.h>
>> +
>> +#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_clear(struct reset_controller_dev *rcdev,
>> + unsigned long id)
>> +{
>> + 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));
>> + writel(reg & ~BIT(offset), data->membase + (bank * reg_width));
>> +
>> + spin_unlock_irqrestore(&data->lock, flags);
>> +
>> + return 0;
>> +}
>> +
>> +static int reset_simple_set(struct reset_controller_dev *rcdev,
>> + unsigned long id)
>> +{
>> + 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));
>> + writel(reg | BIT(offset), data->membase + (bank * reg_width));
>> +
>> + spin_unlock_irqrestore(&data->lock, flags);
>> +
>> + return 0;
>> +}
>
> So these two functions look strikingly similar, apart from the OR / AND
> NEG part.
> What about a unified bit access function then and two tiny wrappers for
> set/clear?
>
> Cheers,
> Andre.
>
>
>> +
>> +static int reset_simple_status(struct reset_controller_dev *rcdev,
>> + unsigned long id)
>> +{
>> + 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);
>> + u32 reg;
>> +
>> + reg = readl(data->membase + (bank * reg_width));
>> +
>> + return !(reg & BIT(offset));
>> +}
>> +
>> +const struct reset_control_ops reset_simple_ops = {
>> + .assert = reset_simple_set,
>> + .deassert = reset_simple_clear,
>> + .status = reset_simple_status,
>> +};
>> +
>> +const struct reset_control_ops reset_simple_ops_inv = {
>> + .assert = reset_simple_clear,
>> + .deassert = reset_simple_set,
>> +};
>> diff --git a/drivers/reset/reset-simple.h b/drivers/reset/reset-simple.h
>> new file mode 100644
>> index 0000000000000..421a0795a2372
>> --- /dev/null
>> +++ b/drivers/reset/reset-simple.h
>> @@ -0,0 +1,53 @@
>> +/*
>> + * Simple Reset Controller ops
>> + *
>> + * Based on Allwinner SoCs Reset Controller driver
>> + *
>> + * Copyright 2013 Maxime Ripard
>> + *
>> + * Maxime Ripard <maxime.ripard@free-electrons.com>
>> + *
>> + * 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 <linux/io.h>
>> +#include <linux/reset-controller.h>
>> +#include <linux/spinlock.h>
>> +
>> +struct reset_simple_data {
>> + spinlock_t lock;
>> + void __iomem *membase;
>> + struct reset_controller_dev rcdev;
>> +};
>> +
>> +extern const struct reset_control_ops reset_simple_ops;
>> +extern const struct reset_control_ops reset_simple_ops_inv;
>> +
>> +static inline int devm_reset_controller_register_simple(struct device *dev,
>> + void __iomem *membase,
>> + unsigned int nr_resets,
>> + bool inverted)
>> +{
>> + struct reset_simple_data *data;
>> +
>> + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>> + if (!data)
>> + return -ENOMEM;
>> +
>> + spin_lock_init(&data->lock);
>> +
>> + data->rcdev.owner = THIS_MODULE;
>> + data->rcdev.nr_resets = nr_resets;
>> + data->rcdev.ops = inverted ? &reset_simple_ops_inv : &reset_simple_ops;
>> + data->rcdev.of_node = dev->of_node;
>> +
>> + return devm_reset_controller_register(dev, &data->rcdev);
>> +}
>> +
>> +#endif /* __RESET_SIMPLE_H__ */
>> diff --git a/drivers/reset/reset-socfpga.c b/drivers/reset/reset-socfpga.c
>> index 07224c0198920..6031a3873bc8f 100644
>> --- a/drivers/reset/reset-socfpga.c
>> +++ b/drivers/reset/reset-socfpga.c
>> @@ -25,83 +25,16 @@
>> #include <linux/spinlock.h>
>> #include <linux/types.h>
>>
>> -#define BANK_INCREMENT 4
>> -#define NR_BANKS 8
>> -
>> -struct socfpga_reset_data {
>> - spinlock_t lock;
>> - void __iomem *membase;
>> - struct reset_controller_dev rcdev;
>> -};
>> -
>> -static int socfpga_reset_assert(struct reset_controller_dev *rcdev,
>> - unsigned long id)
>> -{
>> - struct socfpga_reset_data *data = container_of(rcdev,
>> - struct socfpga_reset_data,
>> - rcdev);
>> - int bank = id / BITS_PER_LONG;
>> - int offset = id % BITS_PER_LONG;
>> - unsigned long flags;
>> - u32 reg;
>> -
>> - spin_lock_irqsave(&data->lock, flags);
>> -
>> - reg = readl(data->membase + (bank * BANK_INCREMENT));
>> - writel(reg | BIT(offset), data->membase + (bank * BANK_INCREMENT));
>> - spin_unlock_irqrestore(&data->lock, flags);
>> -
>> - return 0;
>> -}
>> -
>> -static int socfpga_reset_deassert(struct reset_controller_dev *rcdev,
>> - unsigned long id)
>> -{
>> - struct socfpga_reset_data *data = container_of(rcdev,
>> - struct socfpga_reset_data,
>> - rcdev);
>> -
>> - int bank = id / BITS_PER_LONG;
>> - int offset = id % BITS_PER_LONG;
>> - unsigned long flags;
>> - u32 reg;
>> -
>> - spin_lock_irqsave(&data->lock, flags);
>> -
>> - reg = readl(data->membase + (bank * BANK_INCREMENT));
>> - writel(reg & ~BIT(offset), data->membase + (bank * BANK_INCREMENT));
>> +#include "reset-simple.h"
>>
>> - spin_unlock_irqrestore(&data->lock, flags);
>> -
>> - return 0;
>> -}
>> -
>> -static int socfpga_reset_status(struct reset_controller_dev *rcdev,
>> - unsigned long id)
>> -{
>> - struct socfpga_reset_data *data = container_of(rcdev,
>> - struct socfpga_reset_data, rcdev);
>> - int bank = id / BITS_PER_LONG;
>> - int offset = id % BITS_PER_LONG;
>> - u32 reg;
>> -
>> - reg = readl(data->membase + (bank * BANK_INCREMENT));
>> -
>> - return !(reg & BIT(offset));
>> -}
>> -
>> -static const struct reset_control_ops socfpga_reset_ops = {
>> - .assert = socfpga_reset_assert,
>> - .deassert = socfpga_reset_deassert,
>> - .status = socfpga_reset_status,
>> -};
>> +#define NR_BANKS 8
>>
>> static int socfpga_reset_probe(struct platform_device *pdev)
>> {
>> - struct socfpga_reset_data *data;
>> struct resource *res;
>> struct device *dev = &pdev->dev;
>> struct device_node *np = dev->of_node;
>> + void __iomem *membase;
>> u32 modrst_offset;
>>
>> /*
>> @@ -114,29 +47,20 @@ static int socfpga_reset_probe(struct platform_device *pdev)
>> return -EINVAL;
>> }
>>
>> - 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);
>> + membase = devm_ioremap_resource(&pdev->dev, res);
>> + if (IS_ERR(membase))
>> + return PTR_ERR(membase);
>>
>> if (of_property_read_u32(np, "altr,modrst-offset", &modrst_offset)) {
>> dev_warn(dev, "missing altr,modrst-offset property, assuming 0x10!\n");
>> modrst_offset = 0x10;
>> }
>> - data->membase += modrst_offset;
>> -
>> - spin_lock_init(&data->lock);
>> -
>> - data->rcdev.owner = THIS_MODULE;
>> - data->rcdev.nr_resets = NR_BANKS * BITS_PER_LONG;
>> - data->rcdev.ops = &socfpga_reset_ops;
>> - data->rcdev.of_node = pdev->dev.of_node;
>> + membase += modrst_offset;
>>
>> - return devm_reset_controller_register(dev, &data->rcdev);
>> + return devm_reset_controller_register_simple(&pdev->dev, membase,
>> + NR_BANKS * BITS_PER_LONG,
>> + false);
>> }
>>
>> static const struct of_device_id socfpga_reset_dt_ids[] = {
>> diff --git a/drivers/reset/reset-stm32.c b/drivers/reset/reset-stm32.c
>> index 3a7c8527e66af..15d89d66863d8 100644
>> --- a/drivers/reset/reset-stm32.c
>> +++ b/drivers/reset/reset-stm32.c
>> @@ -16,58 +16,7 @@
>> #include <linux/spinlock.h>
>> #include <linux/types.h>
>>
>> -struct stm32_reset_data {
>> - spinlock_t lock;
>> - void __iomem *membase;
>> - struct reset_controller_dev rcdev;
>> -};
>> -
>> -static int stm32_reset_assert(struct reset_controller_dev *rcdev,
>> - unsigned long id)
>> -{
>> - struct stm32_reset_data *data = container_of(rcdev,
>> - struct stm32_reset_data,
>> - rcdev);
>> - int bank = id / BITS_PER_LONG;
>> - int offset = id % BITS_PER_LONG;
>> - unsigned long flags;
>> - u32 reg;
>> -
>> - spin_lock_irqsave(&data->lock, flags);
>> -
>> - reg = readl(data->membase + (bank * 4));
>> - writel(reg | BIT(offset), data->membase + (bank * 4));
>> -
>> - spin_unlock_irqrestore(&data->lock, flags);
>> -
>> - return 0;
>> -}
>> -
>> -static int stm32_reset_deassert(struct reset_controller_dev *rcdev,
>> - unsigned long id)
>> -{
>> - struct stm32_reset_data *data = container_of(rcdev,
>> - struct stm32_reset_data,
>> - rcdev);
>> - int bank = id / BITS_PER_LONG;
>> - int offset = id % BITS_PER_LONG;
>> - unsigned long flags;
>> - u32 reg;
>> -
>> - spin_lock_irqsave(&data->lock, flags);
>> -
>> - reg = readl(data->membase + (bank * 4));
>> - writel(reg & ~BIT(offset), data->membase + (bank * 4));
>> -
>> - spin_unlock_irqrestore(&data->lock, flags);
>> -
>> - return 0;
>> -}
>> -
>> -static const struct reset_control_ops stm32_reset_ops = {
>> - .assert = stm32_reset_assert,
>> - .deassert = stm32_reset_deassert,
>> -};
>> +#include "reset-simple.h"
>>
>> static const struct of_device_id stm32_reset_dt_ids[] = {
>> { .compatible = "st,stm32-rcc", },
>> @@ -76,26 +25,22 @@ static const struct of_device_id stm32_reset_dt_ids[] = {
>>
>> static int stm32_reset_probe(struct platform_device *pdev)
>> {
>> - struct stm32_reset_data *data;
>> + struct reset_simple_data *data;
>> struct resource *res;
>> + void __iomem *membase;
>>
>> 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 = &stm32_reset_ops;
>> - data->rcdev.of_node = pdev->dev.of_node;
>> + membase = devm_ioremap_resource(&pdev->dev, res);
>> + if (IS_ERR(membase))
>> + return PTR_ERR(membase);
>>
>> - return devm_reset_controller_register(&pdev->dev, &data->rcdev);
>> + return devm_reset_controller_register_simple(&pdev->dev, membase,
>> + resource_size(res) * 8,
>> + false);
>> }
>>
>> static struct platform_driver stm32_reset_driver = {
>> diff --git a/drivers/reset/reset-sunxi.c b/drivers/reset/reset-sunxi.c
>> index cd585cd2f04dd..60745dd6f70a6 100644
>> --- a/drivers/reset/reset-sunxi.c
>> +++ b/drivers/reset/reset-sunxi.c
>> @@ -22,64 +22,11 @@
>> #include <linux/spinlock.h>
>> #include <linux/types.h>
>>
>> -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;
>> @@ -108,7 +55,7 @@ static int sunxi_reset_init(struct device_node *np)
>>
>> data->rcdev.owner = THIS_MODULE;
>> data->rcdev.nr_resets = size * 32;
>> - data->rcdev.ops = &sunxi_reset_ops;
>> + data->rcdev.ops = &reset_simple_ops_inv;
>> data->rcdev.of_node = np;
>>
>> return reset_controller_register(&data->rcdev);
>> @@ -147,26 +94,17 @@ static const struct of_device_id sunxi_reset_dt_ids[] = {
>>
>> 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;
>> + void __iomem *membase;
>>
>> 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) * 32;
>> - data->rcdev.ops = &sunxi_reset_ops;
>> - data->rcdev.of_node = pdev->dev.of_node;
>> + membase = devm_ioremap_resource(&pdev->dev, res);
>> + if (IS_ERR(membase))
>> + return PTR_ERR(membase);
>>
>> - return devm_reset_controller_register(&pdev->dev, &data->rcdev);
>> + return devm_reset_controller_register_simple(&pdev->dev, membase,
>> + resource_size(res) * 32,
>> + true);
>> }
>>
>> static struct platform_driver sunxi_reset_driver = {
>>

\
 
 \ /
  Last update: 2017-03-08 13:53    [W:0.090 / U:0.208 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site