1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved 4 * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics. 5 */ 6 7 #include <common.h> 8 #include <dm.h> 9 #include <errno.h> 10 #include <reset-uclass.h> 11 #include <asm/io.h> 12 13 /* reset clear offset for STM32MP RCC */ 14 #define RCC_CL 0x4 15 16 enum rcc_type { 17 RCC_STM32 = 0, 18 RCC_STM32MP, 19 }; 20 21 struct stm32_reset_priv { 22 fdt_addr_t base; 23 }; 24 25 static int stm32_reset_request(struct reset_ctl *reset_ctl) 26 { 27 return 0; 28 } 29 30 static int stm32_reset_free(struct reset_ctl *reset_ctl) 31 { 32 return 0; 33 } 34 35 static int stm32_reset_assert(struct reset_ctl *reset_ctl) 36 { 37 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 38 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 39 int offset = reset_ctl->id % BITS_PER_LONG; 40 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 41 reset_ctl->id, bank, offset); 42 43 if (dev_get_driver_data(reset_ctl->dev) == RCC_STM32MP) 44 /* reset assert is done in rcc set register */ 45 writel(BIT(offset), priv->base + bank); 46 else 47 setbits_le32(priv->base + bank, BIT(offset)); 48 49 return 0; 50 } 51 52 static int stm32_reset_deassert(struct reset_ctl *reset_ctl) 53 { 54 struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev); 55 int bank = (reset_ctl->id / BITS_PER_LONG) * 4; 56 int offset = reset_ctl->id % BITS_PER_LONG; 57 debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__, 58 reset_ctl->id, bank, offset); 59 60 if (dev_get_driver_data(reset_ctl->dev) == RCC_STM32MP) 61 /* reset deassert is done in rcc clr register */ 62 writel(BIT(offset), priv->base + bank + RCC_CL); 63 else 64 clrbits_le32(priv->base + bank, BIT(offset)); 65 66 return 0; 67 } 68 69 static const struct reset_ops stm32_reset_ops = { 70 .request = stm32_reset_request, 71 .free = stm32_reset_free, 72 .rst_assert = stm32_reset_assert, 73 .rst_deassert = stm32_reset_deassert, 74 }; 75 76 static int stm32_reset_probe(struct udevice *dev) 77 { 78 struct stm32_reset_priv *priv = dev_get_priv(dev); 79 80 priv->base = dev_read_addr(dev); 81 if (priv->base == FDT_ADDR_T_NONE) { 82 /* for MFD, get address of parent */ 83 priv->base = dev_read_addr(dev->parent); 84 if (priv->base == FDT_ADDR_T_NONE) 85 return -EINVAL; 86 } 87 88 return 0; 89 } 90 91 static const struct udevice_id stm32_reset_ids[] = { 92 { .compatible = "st,stm32mp1-rcc-rst", .data = RCC_STM32MP }, 93 { } 94 }; 95 96 U_BOOT_DRIVER(stm32_rcc_reset) = { 97 .name = "stm32_rcc_reset", 98 .id = UCLASS_RESET, 99 .of_match = stm32_reset_ids, 100 .probe = stm32_reset_probe, 101 .priv_auto_alloc_size = sizeof(struct stm32_reset_priv), 102 .ops = &stm32_reset_ops, 103 }; 104