drivers/reset/reset-qcom-pdc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2018 The Linux Foundation. All rights reserved.
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/of_device.h>
   8 #include <linux/platform_device.h>
   9 #include <linux/regmap.h>
  10 #include <linux/reset-controller.h>
  11
  12 #include <dt-bindings/reset/qcom,sdm845-pdc.h>
  13
  14 #define RPMH_PDC_SYNC_RESET     0x100
  15
  16 struct qcom_pdc_reset_map {
  17         u8 bit;
  18 };
  19
  20 struct qcom_pdc_reset_data {
  21         struct reset_controller_dev rcdev;
  22         struct regmap *regmap;
  23 };
  24
  25 static const struct regmap_config sdm845_pdc_regmap_config = {
  26         .name           = "pdc-reset",
  27         .reg_bits       = 32,
  28         .reg_stride     = 4,
  29         .val_bits       = 32,
  30         .max_register   = 0x20000,
  31         .fast_io        = true,
  32 };
  33
  34 static const struct qcom_pdc_reset_map sdm845_pdc_resets[] = {
  35         [PDC_APPS_SYNC_RESET] = {0},
  36         [PDC_SP_SYNC_RESET] = {1},
  37         [PDC_AUDIO_SYNC_RESET] = {2},
  38         [PDC_SENSORS_SYNC_RESET] = {3},
  39         [PDC_AOP_SYNC_RESET] = {4},
  40         [PDC_DEBUG_SYNC_RESET] = {5},
  41         [PDC_GPU_SYNC_RESET] = {6},
  42         [PDC_DISPLAY_SYNC_RESET] = {7},
  43         [PDC_COMPUTE_SYNC_RESET] = {8},
  44         [PDC_MODEM_SYNC_RESET] = {9},
  45 };
  46
  47 static inline struct qcom_pdc_reset_data *to_qcom_pdc_reset_data(
  48                                 struct reset_controller_dev *rcdev)
  49 {
  50         return container_of(rcdev, struct qcom_pdc_reset_data, rcdev);
  51 }
  52
  53 static int qcom_pdc_control_assert(struct reset_controller_dev *rcdev,
  54                                         unsigned long idx)
  55 {
  56         struct qcom_pdc_reset_data *data = to_qcom_pdc_reset_data(rcdev);
  57
  58         return regmap_update_bits(data->regmap, RPMH_PDC_SYNC_RESET,
  59                                   BIT(sdm845_pdc_resets[idx].bit),
  60                                   BIT(sdm845_pdc_resets[idx].bit));
  61 }
  62
  63 static int qcom_pdc_control_deassert(struct reset_controller_dev *rcdev,
  64                                         unsigned long idx)
  65 {
  66         struct qcom_pdc_reset_data *data = to_qcom_pdc_reset_data(rcdev);
  67
  68         return regmap_update_bits(data->regmap, RPMH_PDC_SYNC_RESET,
  69                                   BIT(sdm845_pdc_resets[idx].bit), 0);
  70 }
  71
  72 static const struct reset_control_ops qcom_pdc_reset_ops = {
  73         .assert = qcom_pdc_control_assert,
  74         .deassert = qcom_pdc_control_deassert,
  75 };
  76
  77 static int qcom_pdc_reset_probe(struct platform_device *pdev)
  78 {
  79         struct qcom_pdc_reset_data *data;
  80         struct device *dev = &pdev->dev;
  81         void __iomem *base;
  82         struct resource *res;
  83
  84         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
  85         if (!data)
  86                 return -ENOMEM;
  87
  88         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  89         base = devm_ioremap_resource(dev, res);
  90         if (IS_ERR(base))
  91                 return PTR_ERR(base);
  92
  93         data->regmap = devm_regmap_init_mmio(dev, base,
  94                                              &sdm845_pdc_regmap_config);
  95         if (IS_ERR(data->regmap)) {
  96                 dev_err(dev, "Unable to initialize regmap\n");
  97                 return PTR_ERR(data->regmap);
  98         }
  99
 100         data->rcdev.owner = THIS_MODULE;
 101         data->rcdev.ops = &qcom_pdc_reset_ops;
 102         data->rcdev.nr_resets = ARRAY_SIZE(sdm845_pdc_resets);
 103         data->rcdev.of_node = dev->of_node;
 104
 105         return devm_reset_controller_register(dev, &data->rcdev);
 106 }
 107
 108 static const struct of_device_id qcom_pdc_reset_of_match[] = {
 109         { .compatible = "qcom,sdm845-pdc-global" },
 110         {}
 111 };
 112 MODULE_DEVICE_TABLE(of, qcom_pdc_reset_of_match);
 113
 114 static struct platform_driver qcom_pdc_reset_driver = {
 115         .probe = qcom_pdc_reset_probe,
 116         .driver = {
 117                 .name = "qcom_pdc_reset",
 118                 .of_match_table = qcom_pdc_reset_of_match,
 119         },
 120 };
 121 module_platform_driver(qcom_pdc_reset_driver);
 122
 123 MODULE_DESCRIPTION("Qualcomm PDC Reset Driver");
 124 MODULE_LICENSE("GPL v2");