LXR uboot/drivers/reset/stm32-reset.c

   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 <stm32_rcc.h>
  12#include <asm/io.h>
  13
  14/* reset clear offset for STM32MP RCC */
  15#define RCC_CL 0x4
  16
  17struct stm32_reset_priv {
  18        fdt_addr_t base;
  19};
  20
  21static int stm32_reset_request(struct reset_ctl *reset_ctl)
  22{
  23        return 0;
  24}
  25
  26static int stm32_reset_free(struct reset_ctl *reset_ctl)
  27{
  28        return 0;
  29}
  30
  31static int stm32_reset_assert(struct reset_ctl *reset_ctl)
  32{
  33        struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  34        int bank = (reset_ctl->id / BITS_PER_LONG) * 4;
  35        int offset = reset_ctl->id % BITS_PER_LONG;
  36        debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__,
  37              reset_ctl->id, bank, offset);
  38
  39        if (dev_get_driver_data(reset_ctl->dev) == STM32MP1)
  40                /* reset assert is done in rcc set register */
  41                writel(BIT(offset), priv->base + bank);
  42        else
  43                setbits_le32(priv->base + bank, BIT(offset));
  44
  45        return 0;
  46}
  47
  48static int stm32_reset_deassert(struct reset_ctl *reset_ctl)
  49{
  50        struct stm32_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  51        int bank = (reset_ctl->id / BITS_PER_LONG) * 4;
  52        int offset = reset_ctl->id % BITS_PER_LONG;
  53        debug("%s: reset id = %ld bank = %d offset = %d)\n", __func__,
  54              reset_ctl->id, bank, offset);
  55
  56        if (dev_get_driver_data(reset_ctl->dev) == STM32MP1)
  57                /* reset deassert is done in rcc clr register */
  58                writel(BIT(offset), priv->base + bank + RCC_CL);
  59        else
  60                clrbits_le32(priv->base + bank, BIT(offset));
  61
  62        return 0;
  63}
  64
  65static const struct reset_ops stm32_reset_ops = {
  66        .request        = stm32_reset_request,
  67        .free           = stm32_reset_free,
  68        .rst_assert     = stm32_reset_assert,
  69        .rst_deassert   = stm32_reset_deassert,
  70};
  71
  72static int stm32_reset_probe(struct udevice *dev)
  73{
  74        struct stm32_reset_priv *priv = dev_get_priv(dev);
  75
  76        priv->base = dev_read_addr(dev);
  77        if (priv->base == FDT_ADDR_T_NONE) {
  78                /* for MFD, get address of parent */
  79                priv->base = dev_read_addr(dev->parent);
  80                if (priv->base == FDT_ADDR_T_NONE)
  81                        return -EINVAL;
  82        }
  83
  84        return 0;
  85}
  86
  87U_BOOT_DRIVER(stm32_rcc_reset) = {
  88        .name                   = "stm32_rcc_reset",
  89        .id                     = UCLASS_RESET,
  90        .probe                  = stm32_reset_probe,
  91        .priv_auto_alloc_size   = sizeof(struct stm32_reset_priv),
  92        .ops                    = &stm32_reset_ops,
  93};
  94