drivers/scsi/ufs/cdns-pltfrm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Platform UFS Host driver for Cadence controller
   4  *
   5  * Copyright (C) 2018 Cadence Design Systems, Inc.
   6  *
   7  * Authors:
   8  *      Jan Kotas <jank@cadence.com>
   9  *
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/of.h>
  16 #include <linux/time.h>
  17
  18 #include "ufshcd-pltfrm.h"
  19
  20 #define CDNS_UFS_REG_HCLKDIV    0xFC
  21 #define CDNS_UFS_REG_PHY_XCFGD1 0x113C
  22
  23 /**
  24  * Sets HCLKDIV register value based on the core_clk
  25  * @hba: host controller instance
  26  *
  27  * Return zero for success and non-zero for failure
  28  */
  29 static int cdns_ufs_set_hclkdiv(struct ufs_hba *hba)
  30 {
  31         struct ufs_clk_info *clki;
  32         struct list_head *head = &hba->clk_list_head;
  33         unsigned long core_clk_rate = 0;
  34         u32 core_clk_div = 0;
  35
  36         if (list_empty(head))
  37                 return 0;
  38
  39         list_for_each_entry(clki, head, list) {
  40                 if (IS_ERR_OR_NULL(clki->clk))
  41                         continue;
  42                 if (!strcmp(clki->name, "core_clk"))
  43                         core_clk_rate = clk_get_rate(clki->clk);
  44         }
  45
  46         if (!core_clk_rate) {
  47                 dev_err(hba->dev, "%s: unable to find core_clk rate\n",
  48                         __func__);
  49                 return -EINVAL;
  50         }
  51
  52         core_clk_div = core_clk_rate / USEC_PER_SEC;
  53
  54         ufshcd_writel(hba, core_clk_div, CDNS_UFS_REG_HCLKDIV);
  55         /**
  56          * Make sure the register was updated,
  57          * UniPro layer will not work with an incorrect value.
  58          */
  59         mb();
  60
  61         return 0;
  62 }
  63
  64 /**
  65  * Sets clocks used by the controller
  66  * @hba: host controller instance
  67  * @on: if true, enable clocks, otherwise disable
  68  * @status: notify stage (pre, post change)
  69  *
  70  * Return zero for success and non-zero for failure
  71  */
  72 static int cdns_ufs_setup_clocks(struct ufs_hba *hba, bool on,
  73                                  enum ufs_notify_change_status status)
  74 {
  75         if ((!on) || (status == PRE_CHANGE))
  76                 return 0;
  77
  78         return cdns_ufs_set_hclkdiv(hba);
  79 }
  80
  81 /**
  82  * cdns_ufs_init - performs additional ufs initialization
  83  * @hba: host controller instance
  84  *
  85  * Returns status of initialization
  86  */
  87 static int cdns_ufs_init(struct ufs_hba *hba)
  88 {
  89         int status = 0;
  90
  91         if (hba->vops && hba->vops->phy_initialization)
  92                 status = hba->vops->phy_initialization(hba);
  93
  94         return status;
  95 }
  96
  97 /**
  98  * cdns_ufs_m31_16nm_phy_initialization - performs m31 phy initialization
  99  * @hba: host controller instance
 100  *
 101  * Always returns 0
 102  */
 103 static int cdns_ufs_m31_16nm_phy_initialization(struct ufs_hba *hba)
 104 {
 105         u32 data;
 106
 107         /* Increase RX_Advanced_Min_ActivateTime_Capability */
 108         data = ufshcd_readl(hba, CDNS_UFS_REG_PHY_XCFGD1);
 109         data |= BIT(24);
 110         ufshcd_writel(hba, data, CDNS_UFS_REG_PHY_XCFGD1);
 111
 112         return 0;
 113 }
 114
 115 static const struct ufs_hba_variant_ops cdns_ufs_pltfm_hba_vops = {
 116         .name = "cdns-ufs-pltfm",
 117         .setup_clocks = cdns_ufs_setup_clocks,
 118 };
 119
 120 static const struct ufs_hba_variant_ops cdns_ufs_m31_16nm_pltfm_hba_vops = {
 121         .name = "cdns-ufs-pltfm",
 122         .init = cdns_ufs_init,
 123         .setup_clocks = cdns_ufs_setup_clocks,
 124         .phy_initialization = cdns_ufs_m31_16nm_phy_initialization,
 125 };
 126
 127 static const struct of_device_id cdns_ufs_of_match[] = {
 128         {
 129                 .compatible = "cdns,ufshc",
 130                 .data =  &cdns_ufs_pltfm_hba_vops,
 131         },
 132         {
 133                 .compatible = "cdns,ufshc-m31-16nm",
 134                 .data =  &cdns_ufs_m31_16nm_pltfm_hba_vops,
 135         },
 136         { },
 137 };
 138
 139 MODULE_DEVICE_TABLE(of, cdns_ufs_of_match);
 140
 141 /**
 142  * cdns_ufs_pltfrm_probe - probe routine of the driver
 143  * @pdev: pointer to platform device handle
 144  *
 145  * Return zero for success and non-zero for failure
 146  */
 147 static int cdns_ufs_pltfrm_probe(struct platform_device *pdev)
 148 {
 149         int err;
 150         const struct of_device_id *of_id;
 151         struct ufs_hba_variant_ops *vops;
 152         struct device *dev = &pdev->dev;
 153
 154         of_id = of_match_node(cdns_ufs_of_match, dev->of_node);
 155         vops = (struct ufs_hba_variant_ops *)of_id->data;
 156
 157         /* Perform generic probe */
 158         err = ufshcd_pltfrm_init(pdev, vops);
 159         if (err)
 160                 dev_err(dev, "ufshcd_pltfrm_init() failed %d\n", err);
 161
 162         return err;
 163 }
 164
 165 /**
 166  * cdns_ufs_pltfrm_remove - removes the ufs driver
 167  * @pdev: pointer to platform device handle
 168  *
 169  * Always returns 0
 170  */
 171 static int cdns_ufs_pltfrm_remove(struct platform_device *pdev)
 172 {
 173         struct ufs_hba *hba =  platform_get_drvdata(pdev);
 174
 175         ufshcd_remove(hba);
 176         return 0;
 177 }
 178
 179 static const struct dev_pm_ops cdns_ufs_dev_pm_ops = {
 180         .suspend         = ufshcd_pltfrm_suspend,
 181         .resume          = ufshcd_pltfrm_resume,
 182         .runtime_suspend = ufshcd_pltfrm_runtime_suspend,
 183         .runtime_resume  = ufshcd_pltfrm_runtime_resume,
 184         .runtime_idle    = ufshcd_pltfrm_runtime_idle,
 185 };
 186
 187 static struct platform_driver cdns_ufs_pltfrm_driver = {
 188         .probe  = cdns_ufs_pltfrm_probe,
 189         .remove = cdns_ufs_pltfrm_remove,
 190         .driver = {
 191                 .name   = "cdns-ufshcd",
 192                 .pm     = &cdns_ufs_dev_pm_ops,
 193                 .of_match_table = cdns_ufs_of_match,
 194         },
 195 };
 196
 197 module_platform_driver(cdns_ufs_pltfrm_driver);
 198
 199 MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
 200 MODULE_DESCRIPTION("Cadence UFS host controller platform driver");
 201 MODULE_LICENSE("GPL v2");
 202 MODULE_VERSION(UFSHCD_DRIVER_VERSION);