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 /* reset clear offset for STM32MP RCC */ 15 #define RCC_CL 0x4 16 17 enum rcc_type { 18 RCC_STM32 = 0, 19 RCC_STM32MP, 20 }; 21 22 struct stm32_reset_priv { 23 fdt_addr_t base; 24 }; 25 26 static int stm32_reset_request(struct reset_ctl *reset_ctl) 27 { 28 return 0; 29 } 30 31 static int stm32_reset_free(struct reset_ctl *reset_ctl) 32 { 33 return 0; 34 } 35 36 static int stm32_reset_assert(struct reset_ctl *reset_ctl) 37 { 38 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 39 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 40 int offset = reset_ctl->id % BITS_PER_LONG; 41 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 42 reset_ctl->id, bank, offset); 43 44 if (dev_get_driver_data(reset_ctl->dev) == RCC_STM32MP) 45 /* reset assert is done in rcc set register */ 46 writel(BIT(offset), priv->base + bank); 47 else 48 setbits_le32(priv->base + bank, BIT(offset)); 49 50 return 0; 51 } 52 53 static int stm32_reset_deassert(struct reset_ctl *reset_ctl) 54 { 55 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 56 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 57 int offset = reset_ctl->id % BITS_PER_LONG; 58 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 59 reset_ctl->id, bank, offset); 60 61 if (dev_get_driver_data(reset_ctl->dev) == RCC_STM32MP) 62 /* reset deassert is done in rcc clr register */ 63 writel(BIT(offset), priv->base + bank + RCC_CL); 64 else 65 clrbits_le32(priv->base + bank, BIT(offset)); 66 67 return 0; 68 } 69 70 static const struct reset_ops stm32_reset_ops = { 71 .request = stm32_reset_request, 72 .free = stm32_reset_free, 73 .rst_assert = stm32_reset_assert, 74 .rst_deassert = stm32_reset_deassert, 75 }; 76 77 static int stm32_reset_probe(struct udevice *dev) 78 { 79 struct stm32_reset_priv *priv = dev_get_priv(dev); 80 81 priv->base = dev_read_addr(dev); 82 if (priv->base == FDT_ADDR_T_NONE) { 83 /* for MFD, get address of parent */ 84 priv->base = dev_read_addr(dev->parent); 85 if (priv->base == FDT_ADDR_T_NONE) 86 return -EINVAL; 87 } 88 89 return 0; 90 } 91 92 static const struct udevice_id stm32_reset_ids[] = { 93 { .compatible = "st,stm32mp1-rcc-rst", .data = RCC_STM32MP }, 94 { } 95 }; 96 97 U_BOOT_DRIVER(stm32_rcc_reset) = { 98 .name = "stm32_rcc_reset", 99 .id = UCLASS_RESET, 100 .of_match = stm32_reset_ids, 101 .probe = stm32_reset_probe, 102 .priv_auto_alloc_size = sizeof(struct stm32_reset_priv), 103 .ops = &stm32_reset_ops, 104 }; 105