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

   1// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
   2/*
   3 * Copyright (C) 2018 Amarula Solutions.
   4 * Author: Jagan Teki <jagan@amarulasolutions.com>
   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#include <dm/lists.h>
  13#include <linux/log2.h>
  14#include <asm/arch/ccu.h>
  15
  16struct sunxi_reset_priv {
  17        void *base;
  18        ulong count;
  19        const struct ccu_desc *desc;
  20};
  21
  22static const struct ccu_reset *priv_to_reset(struct sunxi_reset_priv *priv,
  23                                             unsigned long id)
  24{
  25        return  &priv->desc->resets[id];
  26}
  27
  28static int sunxi_reset_request(struct reset_ctl *reset_ctl)
  29{
  30        struct sunxi_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  31
  32        debug("%s: (RST#%ld)\n", __func__, reset_ctl->id);
  33
  34        if (reset_ctl->id >= priv->count)
  35                return -EINVAL;
  36
  37        return 0;
  38}
  39
  40static int sunxi_reset_free(struct reset_ctl *reset_ctl)
  41{
  42        debug("%s: (RST#%ld)\n", __func__, reset_ctl->id);
  43
  44        return 0;
  45}
  46
  47static int sunxi_set_reset(struct reset_ctl *reset_ctl, bool on)
  48{
  49        struct sunxi_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  50        const struct ccu_reset *reset = priv_to_reset(priv, reset_ctl->id);
  51        u32 reg;
  52
  53        if (!(reset->flags & CCU_RST_F_IS_VALID)) {
  54                printf("%s: (RST#%ld) unhandled\n", __func__, reset_ctl->id);
  55                return 0;
  56        }
  57
  58        debug("%s: (RST#%ld) off#0x%x, BIT(%d)\n", __func__,
  59              reset_ctl->id, reset->off, ilog2(reset->bit));
  60
  61        reg = readl(priv->base + reset->off);
  62        if (on)
  63                reg |= reset->bit;
  64        else
  65                reg &= ~reset->bit;
  66
  67        writel(reg, priv->base + reset->off);
  68
  69        return 0;
  70}
  71
  72static int sunxi_reset_assert(struct reset_ctl *reset_ctl)
  73{
  74        return sunxi_set_reset(reset_ctl, false);
  75}
  76
  77static int sunxi_reset_deassert(struct reset_ctl *reset_ctl)
  78{
  79        return sunxi_set_reset(reset_ctl, true);
  80}
  81
  82struct reset_ops sunxi_reset_ops = {
  83        .request = sunxi_reset_request,
  84        .free = sunxi_reset_free,
  85        .rst_assert = sunxi_reset_assert,
  86        .rst_deassert = sunxi_reset_deassert,
  87};
  88
  89static int sunxi_reset_probe(struct udevice *dev)
  90{
  91        struct sunxi_reset_priv *priv = dev_get_priv(dev);
  92
  93        priv->base = dev_read_addr_ptr(dev);
  94
  95        return 0;
  96}
  97
  98int sunxi_reset_bind(struct udevice *dev, ulong count)
  99{
 100        struct udevice *rst_dev;
 101        struct sunxi_reset_priv *priv;
 102        int ret;
 103
 104        ret = device_bind_driver_to_node(dev, "sunxi_reset", "reset",
 105                                         dev_ofnode(dev), &rst_dev);
 106        if (ret) {
 107                debug("failed to bind sunxi_reset driver (ret=%d)\n", ret);
 108                return ret;
 109        }
 110        priv = malloc(sizeof(struct sunxi_reset_priv));
 111        priv->count = count;
 112        priv->desc = (const struct ccu_desc *)dev_get_driver_data(dev);
 113        rst_dev->priv = priv;
 114
 115        return 0;
 116}
 117
 118U_BOOT_DRIVER(sunxi_reset) = {
 119        .name           = "sunxi_reset",
 120        .id             = UCLASS_RESET,
 121        .ops            = &sunxi_reset_ops,
 122        .probe          = sunxi_reset_probe,
 123        .priv_auto_alloc_size = sizeof(struct sunxi_reset_priv),
 124};
 125