stm32-reset.c 2.3 KB

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  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. #include <common.h>
  7. #include <dm.h>
  8. #include <errno.h>
  9. #include <reset-uclass.h>
  10. #include <stm32_rcc.h>
  11. #include <asm/io.h>
  12. /* reset clear offset for STM32MP RCC */
  13. #define RCC_CL 0x4
  14. struct stm32_reset_priv {
  15. fdt_addr_t base;
  16. };
  17. static int stm32_reset_request(struct reset_ctl *reset_ctl)
  18. {
  19. return 0;
  20. }
  21. static int stm32_reset_free(struct reset_ctl *reset_ctl)
  22. {
  23. return 0;
  24. }
  25. static int stm32_reset_assert(struct reset_ctl *reset_ctl)
  26. {
  27. struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  28. int bank = (reset_ctl->id / BITS_PER_LONG) * 4;
  29. int offset = reset_ctl->id % BITS_PER_LONG;
  30. debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__,
  31. reset_ctl->id, bank, offset);
  32. if (dev_get_driver_data(reset_ctl->dev) == STM32MP1)
  33. /* reset assert is done in rcc set register */
  34. writel(BIT(offset), priv->base + bank);
  35. else
  36. setbits_le32(priv->base + bank, BIT(offset));
  37. return 0;
  38. }
  39. static int stm32_reset_deassert(struct reset_ctl *reset_ctl)
  40. {
  41. struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  42. int bank = (reset_ctl->id / BITS_PER_LONG) * 4;
  43. int offset = reset_ctl->id % BITS_PER_LONG;
  44. debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__,
  45. reset_ctl->id, bank, offset);
  46. if (dev_get_driver_data(reset_ctl->dev) == STM32MP1)
  47. /* reset deassert is done in rcc clr register */
  48. writel(BIT(offset), priv->base + bank + RCC_CL);
  49. else
  50. clrbits_le32(priv->base + bank, BIT(offset));
  51. return 0;
  52. }
  53. static const struct reset_ops stm32_reset_ops = {
  54. .request = stm32_reset_request,
  55. .free = stm32_reset_free,
  56. .rst_assert = stm32_reset_assert,
  57. .rst_deassert = stm32_reset_deassert,
  58. };
  59. static int stm32_reset_probe(struct udevice *dev)
  60. {
  61. struct stm32_reset_priv *priv = dev_get_priv(dev);
  62. priv->base = dev_read_addr(dev);
  63. if (priv->base == FDT_ADDR_T_NONE) {
  64. /* for MFD, get address of parent */
  65. priv->base = dev_read_addr(dev->parent);
  66. if (priv->base == FDT_ADDR_T_NONE)
  67. return -EINVAL;
  68. }
  69. return 0;
  70. }
  71. U_BOOT_DRIVER(stm32_rcc_reset) = {
  72. .name = "stm32_rcc_reset",
  73. .id = UCLASS_RESET,
  74. .probe = stm32_reset_probe,
  75. .priv_auto_alloc_size = sizeof(struct stm32_reset_priv),
  76. .ops = &stm32_reset_ops,
  77. };