diff options
Diffstat (limited to 'drivers/reset')
| -rw-r--r-- | drivers/reset/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/reset/Makefile | 1 | ||||
| -rw-r--r-- | drivers/reset/reset-stm32mp1.c | 115 |
3 files changed, 122 insertions, 0 deletions
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index 1efbc6cc8021..c0b292be1b72 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -97,6 +97,12 @@ config RESET_SIMPLE - Allwinner SoCs - ZTE's zx2967 family +config RESET_STM32MP157 + bool "STM32MP157 Reset Driver" if COMPILE_TEST + default MACH_STM32MP157 + help + This enables the RCC reset controller driver for STM32 MPUs. + config RESET_SUNXI bool "Allwinner SoCs Reset Driver" if COMPILE_TEST && !ARCH_SUNXI default ARCH_SUNXI diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index 132c24f5ddb5..c1261dcfe9ad 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -15,6 +15,7 @@ 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-$(CONFIG_RESET_STM32MP157) += reset-stm32mp1.o obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o diff --git a/drivers/reset/reset-stm32mp1.c b/drivers/reset/reset-stm32mp1.c new file mode 100644 index 000000000000..b221a28041fa --- /dev/null +++ b/drivers/reset/reset-stm32mp1.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) STMicroelectronics 2018 - All Rights Reserved + * Author: Gabriel Fernandez <gabriel.fernandez@st.com> for STMicroelectronics. + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> + +#define CLR_OFFSET 0x4 + +struct stm32_reset_data { + struct reset_controller_dev rcdev; + void __iomem *membase; +}; + +static inline struct stm32_reset_data * +to_stm32_reset_data(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct stm32_reset_data, rcdev); +} + +static int stm32_reset_update(struct reset_controller_dev *rcdev, + unsigned long id, bool assert) +{ + struct stm32_reset_data *data = to_stm32_reset_data(rcdev); + int reg_width = sizeof(u32); + int bank = id / (reg_width * BITS_PER_BYTE); + int offset = id % (reg_width * BITS_PER_BYTE); + void __iomem *addr; + + addr = data->membase + (bank * reg_width); + if (!assert) + addr += CLR_OFFSET; + + writel(BIT(offset), addr); + + return 0; +} + +static int stm32_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return stm32_reset_update(rcdev, id, true); +} + +static int stm32_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return stm32_reset_update(rcdev, id, false); +} + +static int stm32_reset_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct stm32_reset_data *data = to_stm32_reset_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)); +} + +static const struct reset_control_ops stm32_reset_ops = { + .assert = stm32_reset_assert, + .deassert = stm32_reset_deassert, + .status = stm32_reset_status, +}; + +static const struct of_device_id stm32_reset_dt_ids[] = { + { .compatible = "st,stm32mp1-rcc"}, + { /* sentinel */ }, +}; + +static int stm32_reset_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct stm32_reset_data *data; + void __iomem *membase; + struct resource *res; + + 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); + + data->membase = membase; + data->rcdev.owner = THIS_MODULE; + data->rcdev.nr_resets = resource_size(res) * BITS_PER_BYTE; + data->rcdev.ops = &stm32_reset_ops; + data->rcdev.of_node = dev->of_node; + + return devm_reset_controller_register(dev, &data->rcdev); +} + +static struct platform_driver stm32_reset_driver = { + .probe = stm32_reset_probe, + .driver = { + .name = "stm32mp1-reset", + .of_match_table = stm32_reset_dt_ids, + }, +}; + +builtin_platform_driver(stm32_reset_driver); |