From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/clk/stm32/reset-stm32.c | 123 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100644 drivers/clk/stm32/reset-stm32.c (limited to 'drivers/clk/stm32/reset-stm32.c') diff --git a/drivers/clk/stm32/reset-stm32.c b/drivers/clk/stm32/reset-stm32.c new file mode 100644 index 0000000000..e89381528a --- /dev/null +++ b/drivers/clk/stm32/reset-stm32.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) STMicroelectronics 2022 - All Rights Reserved + * Author: Gabriel Fernandez for STMicroelectronics. + */ + +#include +#include +#include +#include +#include +#include + +#include "clk-stm32-core.h" + +#define STM32_RESET_ID_MASK GENMASK(15, 0) + +struct stm32_reset_data { + /* reset lock */ + spinlock_t lock; + struct reset_controller_dev rcdev; + void __iomem *membase; + u32 clear_offset; +}; + +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); + + if (data->clear_offset) { + void __iomem *addr; + + addr = data->membase + (bank * reg_width); + if (!assert) + addr += data->clear_offset; + + writel(BIT(offset), addr); + + } else { + unsigned long flags; + u32 reg; + + spin_lock_irqsave(&data->lock, flags); + + reg = readl(data->membase + (bank * reg_width)); + + if (assert) + reg |= BIT(offset); + else + reg &= ~BIT(offset); + + writel(reg, data->membase + (bank * reg_width)); + + spin_unlock_irqrestore(&data->lock, flags); + } + + 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, +}; + +int stm32_rcc_reset_init(struct device *dev, const struct of_device_id *match, + void __iomem *base) +{ + const struct stm32_rcc_match_data *data = match->data; + struct stm32_reset_data *reset_data = NULL; + + data = match->data; + + reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL); + if (!reset_data) + return -ENOMEM; + + spin_lock_init(&reset_data->lock); + reset_data->membase = base; + reset_data->rcdev.owner = THIS_MODULE; + reset_data->rcdev.ops = &stm32_reset_ops; + reset_data->rcdev.of_node = dev_of_node(dev); + reset_data->rcdev.nr_resets = STM32_RESET_ID_MASK; + reset_data->clear_offset = data->clear_offset; + + return reset_controller_register(&reset_data->rcdev); +} -- cgit v1.2.3