1 /* 2 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved 3 * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <dm.h> 10 #include <errno.h> 11 #include <reset-uclass.h> 12 #include <asm/io.h> 13 14 DECLARE_GLOBAL_DATA_PTR; 15 16 struct stm32_reset_priv { 17 fdt_addr_t base; 18 }; 19 20 static int stm32_reset_request(struct reset_ctl *reset_ctl) 21 { 22 return 0; 23 } 24 25 static int stm32_reset_free(struct reset_ctl *reset_ctl) 26 { 27 return 0; 28 } 29 30 static int stm32_reset_assert(struct reset_ctl *reset_ctl) 31 { 32 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 33 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 34 int offset = reset_ctl->id % BITS_PER_LONG; 35 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 36 reset_ctl->id, bank, offset); 37 38 setbits_le32(priv->base + bank, BIT(offset)); 39 40 return 0; 41 } 42 43 static int stm32_reset_deassert(struct reset_ctl *reset_ctl) 44 { 45 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 46 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 47 int offset = reset_ctl->id % BITS_PER_LONG; 48 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 49 reset_ctl->id, bank, offset); 50 51 clrbits_le32(priv->base + bank, BIT(offset)); 52 53 return 0; 54 } 55 56 static const struct reset_ops stm32_reset_ops = { 57 .request = stm32_reset_request, 58 .free = stm32_reset_free, 59 .rst_assert = stm32_reset_assert, 60 .rst_deassert = stm32_reset_deassert, 61 }; 62 63 static int stm32_reset_probe(struct udevice *dev) 64 { 65 struct stm32_reset_priv *priv = dev_get_priv(dev); 66 67 priv->base = devfdt_get_addr(dev); 68 if (priv->base == FDT_ADDR_T_NONE) 69 return -EINVAL; 70 71 return 0; 72 } 73 74 U_BOOT_DRIVER(stm32_rcc_reset) = { 75 .name = "stm32_rcc_reset", 76 .id = UCLASS_RESET, 77 .probe = stm32_reset_probe, 78 .priv_auto_alloc_size = sizeof(struct stm32_reset_priv), 79 .ops = &stm32_reset_ops, 80 }; 81