1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
4 * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics.
12 #include <reset-uclass.h>
13 #include <stm32_rcc.h>
15 #include <linux/bitops.h>
17 /* reset clear offset for STM32MP RCC */
20 struct stm32_reset_priv {
24 static int stm32_reset_request(struct reset_ctl *reset_ctl)
29 static int stm32_reset_free(struct reset_ctl *reset_ctl)
34 static int stm32_reset_assert(struct reset_ctl *reset_ctl)
36 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev);
37 int bank = (reset_ctl->id / BITS_PER_LONG) * 4;
38 int offset = reset_ctl->id % BITS_PER_LONG;
39 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__,
40 reset_ctl->id, bank, offset);
42 if (dev_get_driver_data(reset_ctl->dev) == STM32MP1)
43 /* reset assert is done in rcc set register */
44 writel(BIT(offset), priv->base + bank);
46 setbits_le32(priv->base + bank, BIT(offset));
51 static int stm32_reset_deassert(struct reset_ctl *reset_ctl)
53 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev);
54 int bank = (reset_ctl->id / BITS_PER_LONG) * 4;
55 int offset = reset_ctl->id % BITS_PER_LONG;
56 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__,
57 reset_ctl->id, bank, offset);
59 if (dev_get_driver_data(reset_ctl->dev) == STM32MP1)
60 /* reset deassert is done in rcc clr register */
61 writel(BIT(offset), priv->base + bank + RCC_CL);
63 clrbits_le32(priv->base + bank, BIT(offset));
68 static const struct reset_ops stm32_reset_ops = {
69 .request = stm32_reset_request,
70 .rfree = stm32_reset_free,
71 .rst_assert = stm32_reset_assert,
72 .rst_deassert = stm32_reset_deassert,
75 static int stm32_reset_probe(struct udevice *dev)
77 struct stm32_reset_priv *priv = dev_get_priv(dev);
79 priv->base = dev_read_addr(dev);
80 if (priv->base == FDT_ADDR_T_NONE) {
81 /* for MFD, get address of parent */
82 priv->base = dev_read_addr(dev->parent);
83 if (priv->base == FDT_ADDR_T_NONE)
90 U_BOOT_DRIVER(stm32_rcc_reset) = {
91 .name = "stm32_rcc_reset",
93 .probe = stm32_reset_probe,
94 .priv_auto_alloc_size = sizeof(struct stm32_reset_priv),
95 .ops = &stm32_reset_ops,