drivers/reset/reset-zynqmp.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2018 Xilinx, Inc.
   4  *
   5  */
   6
   7 #include <linux/err.h>
   8 #include <linux/of.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/reset-controller.h>
  11 #include <linux/firmware/xlnx-zynqmp.h>
  12 #include <linux/of_device.h>
  13
  14 #define ZYNQMP_NR_RESETS (ZYNQMP_PM_RESET_END - ZYNQMP_PM_RESET_START)
  15 #define ZYNQMP_RESET_ID ZYNQMP_PM_RESET_START
  16 #define VERSAL_NR_RESETS        95
  17
  18 struct zynqmp_reset_soc_data {
  19         u32 reset_id;
  20         u32 num_resets;
  21 };
  22
  23 struct zynqmp_reset_data {
  24         struct reset_controller_dev rcdev;
  25         const struct zynqmp_reset_soc_data *data;
  26 };
  27
  28 static inline struct zynqmp_reset_data *
  29 to_zynqmp_reset_data(struct reset_controller_dev *rcdev)
  30 {
  31         return container_of(rcdev, struct zynqmp_reset_data, rcdev);
  32 }
  33
  34 static int zynqmp_reset_assert(struct reset_controller_dev *rcdev,
  35                                unsigned long id)
  36 {
  37         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  38
  39         return zynqmp_pm_reset_assert(priv->data->reset_id + id,
  40                                       PM_RESET_ACTION_ASSERT);
  41 }
  42
  43 static int zynqmp_reset_deassert(struct reset_controller_dev *rcdev,
  44                                  unsigned long id)
  45 {
  46         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  47
  48         return zynqmp_pm_reset_assert(priv->data->reset_id + id,
  49                                       PM_RESET_ACTION_RELEASE);
  50 }
  51
  52 static int zynqmp_reset_status(struct reset_controller_dev *rcdev,
  53                                unsigned long id)
  54 {
  55         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  56         int val, err;
  57
  58         err = zynqmp_pm_reset_get_status(priv->data->reset_id + id, &val);
  59         if (err)
  60                 return err;
  61
  62         return val;
  63 }
  64
  65 static int zynqmp_reset_reset(struct reset_controller_dev *rcdev,
  66                               unsigned long id)
  67 {
  68         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  69
  70         return zynqmp_pm_reset_assert(priv->data->reset_id + id,
  71                                       PM_RESET_ACTION_PULSE);
  72 }
  73
  74 static int zynqmp_reset_of_xlate(struct reset_controller_dev *rcdev,
  75                                  const struct of_phandle_args *reset_spec)
  76 {
  77         return reset_spec->args[0];
  78 }
  79
  80 static const struct zynqmp_reset_soc_data zynqmp_reset_data = {
  81         .reset_id = ZYNQMP_RESET_ID,
  82         .num_resets = ZYNQMP_NR_RESETS,
  83 };
  84
  85 static const struct zynqmp_reset_soc_data versal_reset_data = {
  86         .reset_id = 0,
  87         .num_resets = VERSAL_NR_RESETS,
  88 };
  89
  90 static const struct reset_control_ops zynqmp_reset_ops = {
  91         .reset = zynqmp_reset_reset,
  92         .assert = zynqmp_reset_assert,
  93         .deassert = zynqmp_reset_deassert,
  94         .status = zynqmp_reset_status,
  95 };
  96
  97 static int zynqmp_reset_probe(struct platform_device *pdev)
  98 {
  99         struct zynqmp_reset_data *priv;
 100
 101         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 102         if (!priv)
 103                 return -ENOMEM;
 104
 105         priv->data = of_device_get_match_data(&pdev->dev);
 106         if (!priv->data)
 107                 return -EINVAL;
 108
 109         platform_set_drvdata(pdev, priv);
 110
 111         priv->rcdev.ops = &zynqmp_reset_ops;
 112         priv->rcdev.owner = THIS_MODULE;
 113         priv->rcdev.of_node = pdev->dev.of_node;
 114         priv->rcdev.nr_resets = priv->data->num_resets;
 115         priv->rcdev.of_reset_n_cells = 1;
 116         priv->rcdev.of_xlate = zynqmp_reset_of_xlate;
 117
 118         return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
 119 }
 120
 121 static const struct of_device_id zynqmp_reset_dt_ids[] = {
 122         { .compatible = "xlnx,zynqmp-reset", .data = &zynqmp_reset_data, },
 123         { .compatible = "xlnx,versal-reset", .data = &versal_reset_data, },
 124         { /* sentinel */ },
 125 };
 126
 127 static struct platform_driver zynqmp_reset_driver = {
 128         .probe  = zynqmp_reset_probe,
 129         .driver = {
 130                 .name           = KBUILD_MODNAME,
 131                 .of_match_table = zynqmp_reset_dt_ids,
 132         },
 133 };
 134
 135 static int __init zynqmp_reset_init(void)
 136 {
 137         return platform_driver_register(&zynqmp_reset_driver);
 138 }
 139
 140 arch_initcall(zynqmp_reset_init);