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 <malloc.h>
  11#include <reset-uclass.h>
  12#include <asm/io.h>
  13#include <dm/lists.h>
  14#include <linux/log2.h>
  15#include <asm/arch/ccu.h>
  16
  17struct sunxi_reset_priv {
  18        void *base;
  19        ulong count;
  20        const struct ccu_desc *desc;
  21};
  22
  23static const struct ccu_reset *priv_to_reset(struct sunxi_reset_priv *priv,
  24                                             unsigned long id)
  25{
  26        return  &priv->desc->resets[id];
  27}
  28
  29static int sunxi_reset_request(struct reset_ctl *reset_ctl)
  30{
  31        struct sunxi_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  32
  33        debug("%s: (RST#%ld)\n", __func__, reset_ctl->id);
  34
  35        if (reset_ctl->id >= priv->count)
  36                return -EINVAL;
  37
  38        return 0;
  39}
  40
  41static int sunxi_reset_free(struct reset_ctl *reset_ctl)
  42{
  43        debug("%s: (RST#%ld)\n", __func__, reset_ctl->id);
  44
  45        return 0;
  46}
  47
  48static int sunxi_set_reset(struct reset_ctl *reset_ctl, bool on)
  49{
  50        struct sunxi_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  51        const struct ccu_reset *reset = priv_to_reset(priv, reset_ctl->id);
  52        u32 reg;
  53
  54        if (!(reset->flags & CCU_RST_F_IS_VALID)) {
  55                printf("%s: (RST#%ld) unhandled\n", __func__, reset_ctl->id);
  56                return 0;
  57        }
  58
  59        debug("%s: (RST#%ld) off#0x%x, BIT(%d)\n", __func__,
  60              reset_ctl->id, reset->off, ilog2(reset->bit));
  61
  62        reg = readl(priv->base + reset->off);
  63        if (on)
  64                reg |= reset->bit;
  65        else
  66                reg &= ~reset->bit;
  67
  68        writel(reg, priv->base + reset->off);
  69
  70        return 0;
  71}
  72
  73static int sunxi_reset_assert(struct reset_ctl *reset_ctl)
  74{
  75        return sunxi_set_reset(reset_ctl, false);
  76}
  77
  78static int sunxi_reset_deassert(struct reset_ctl *reset_ctl)
  79{
  80        return sunxi_set_reset(reset_ctl, true);
  81}
  82
  83struct reset_ops sunxi_reset_ops = {
  84        .request = sunxi_reset_request,
  85        .rfree = sunxi_reset_free,
  86        .rst_assert = sunxi_reset_assert,
  87        .rst_deassert = sunxi_reset_deassert,
  88};
  89
  90static int sunxi_reset_probe(struct udevice *dev)
  91{
  92        struct sunxi_reset_priv *priv = dev_get_priv(dev);
  93
  94        priv->base = dev_read_addr_ptr(dev);
  95
  96        return 0;
  97}
  98
  99int sunxi_reset_bind(struct udevice *dev, ulong count)
 100{
 101        struct udevice *rst_dev;
 102        struct sunxi_reset_priv *priv;
 103        int ret;
 104
 105        ret = device_bind_driver_to_node(dev, "sunxi_reset", "reset",
 106                                         dev_ofnode(dev), &rst_dev);
 107        if (ret) {
 108                debug("failed to bind sunxi_reset driver (ret=%d)\n", ret);
 109                return ret;
 110        }
 111        priv = malloc(sizeof(struct sunxi_reset_priv));
 112        priv->count = count;
 113        priv->desc = (const struct ccu_desc *)dev_get_driver_data(dev);
 114        rst_dev->priv = priv;
 115
 116        return 0;
 117}
 118
 119U_BOOT_DRIVER(sunxi_reset) = {
 120        .name           = "sunxi_reset",
 121        .id             = UCLASS_RESET,
 122        .ops            = &sunxi_reset_ops,
 123        .probe          = sunxi_reset_probe,
 124        .priv_auto_alloc_size = sizeof(struct sunxi_reset_priv),
 125};
 126