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  * Called before and after HCE enable bit is set.
  66  * @hba: host controller instance
  67  * @status: notify stage (pre, post change)
  68  *
  69  * Return zero for success and non-zero for failure
  70  */
  71 static int cdns_ufs_hce_enable_notify(struct ufs_hba *hba,
  72                                       enum ufs_notify_change_status status)
  73 {
  74         if (status != PRE_CHANGE)
  75                 return 0;
  76
  77         return cdns_ufs_set_hclkdiv(hba);
  78 }
  79
  80 /**
  81  * Called before and after Link startup is carried out.
  82  * @hba: host controller instance
  83  * @status: notify stage (pre, post change)
  84  *
  85  * Return zero for success and non-zero for failure
  86  */
  87 static int cdns_ufs_link_startup_notify(struct ufs_hba *hba,
  88                                         enum ufs_notify_change_status status)
  89 {
  90         if (status != PRE_CHANGE)
  91                 return 0;
  92
  93         /*
  94          * Some UFS devices have issues if LCC is enabled.
  95          * So we are setting PA_Local_TX_LCC_Enable to 0
  96          * before link startup which will make sure that both host
  97          * and device TX LCC are disabled once link startup is
  98          * completed.
  99          */
 100         ufshcd_dme_set(hba, UIC_ARG_MIB(PA_LOCAL_TX_LCC_ENABLE), 0);
 101
 102         return 0;
 103 }
 104
 105 /**
 106  * cdns_ufs_init - performs additional ufs initialization
 107  * @hba: host controller instance
 108  *
 109  * Returns status of initialization
 110  */
 111 static int cdns_ufs_init(struct ufs_hba *hba)
 112 {
 113         int status = 0;
 114
 115         if (hba->vops && hba->vops->phy_initialization)
 116                 status = hba->vops->phy_initialization(hba);
 117
 118         return status;
 119 }
 120
 121 /**
 122  * cdns_ufs_m31_16nm_phy_initialization - performs m31 phy initialization
 123  * @hba: host controller instance
 124  *
 125  * Always returns 0
 126  */
 127 static int cdns_ufs_m31_16nm_phy_initialization(struct ufs_hba *hba)
 128 {
 129         u32 data;
 130
 131         /* Increase RX_Advanced_Min_ActivateTime_Capability */
 132         data = ufshcd_readl(hba, CDNS_UFS_REG_PHY_XCFGD1);
 133         data |= BIT(24);
 134         ufshcd_writel(hba, data, CDNS_UFS_REG_PHY_XCFGD1);
 135
 136         return 0;
 137 }
 138
 139 static const struct ufs_hba_variant_ops cdns_ufs_pltfm_hba_vops = {
 140         .name = "cdns-ufs-pltfm",
 141         .hce_enable_notify = cdns_ufs_hce_enable_notify,
 142         .link_startup_notify = cdns_ufs_link_startup_notify,
 143 };
 144
 145 static const struct ufs_hba_variant_ops cdns_ufs_m31_16nm_pltfm_hba_vops = {
 146         .name = "cdns-ufs-pltfm",
 147         .init = cdns_ufs_init,
 148         .hce_enable_notify = cdns_ufs_hce_enable_notify,
 149         .link_startup_notify = cdns_ufs_link_startup_notify,
 150         .phy_initialization = cdns_ufs_m31_16nm_phy_initialization,
 151 };
 152
 153 static const struct of_device_id cdns_ufs_of_match[] = {
 154         {
 155                 .compatible = "cdns,ufshc",
 156                 .data =  &cdns_ufs_pltfm_hba_vops,
 157         },
 158         {
 159                 .compatible = "cdns,ufshc-m31-16nm",
 160                 .data =  &cdns_ufs_m31_16nm_pltfm_hba_vops,
 161         },
 162         { },
 163 };
 164
 165 MODULE_DEVICE_TABLE(of, cdns_ufs_of_match);
 166
 167 /**
 168  * cdns_ufs_pltfrm_probe - probe routine of the driver
 169  * @pdev: pointer to platform device handle
 170  *
 171  * Return zero for success and non-zero for failure
 172  */
 173 static int cdns_ufs_pltfrm_probe(struct platform_device *pdev)
 174 {
 175         int err;
 176         const struct of_device_id *of_id;
 177         struct ufs_hba_variant_ops *vops;
 178         struct device *dev = &pdev->dev;
 179
 180         of_id = of_match_node(cdns_ufs_of_match, dev->of_node);
 181         vops = (struct ufs_hba_variant_ops *)of_id->data;
 182
 183         /* Perform generic probe */
 184         err = ufshcd_pltfrm_init(pdev, vops);
 185         if (err)
 186                 dev_err(dev, "ufshcd_pltfrm_init() failed %d\n", err);
 187
 188         return err;
 189 }
 190
 191 /**
 192  * cdns_ufs_pltfrm_remove - removes the ufs driver
 193  * @pdev: pointer to platform device handle
 194  *
 195  * Always returns 0
 196  */
 197 static int cdns_ufs_pltfrm_remove(struct platform_device *pdev)
 198 {
 199         struct ufs_hba *hba =  platform_get_drvdata(pdev);
 200
 201         ufshcd_remove(hba);
 202         return 0;
 203 }
 204
 205 static const struct dev_pm_ops cdns_ufs_dev_pm_ops = {
 206         .suspend         = ufshcd_pltfrm_suspend,
 207         .resume          = ufshcd_pltfrm_resume,
 208         .runtime_suspend = ufshcd_pltfrm_runtime_suspend,
 209         .runtime_resume  = ufshcd_pltfrm_runtime_resume,
 210         .runtime_idle    = ufshcd_pltfrm_runtime_idle,
 211 };
 212
 213 static struct platform_driver cdns_ufs_pltfrm_driver = {
 214         .probe  = cdns_ufs_pltfrm_probe,
 215         .remove = cdns_ufs_pltfrm_remove,
 216         .driver = {
 217                 .name   = "cdns-ufshcd",
 218                 .pm     = &cdns_ufs_dev_pm_ops,
 219                 .of_match_table = cdns_ufs_of_match,
 220         },
 221 };
 222
 223 module_platform_driver(cdns_ufs_pltfrm_driver);
 224
 225 MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
 226 MODULE_DESCRIPTION("Cadence UFS host controller platform driver");
 227 MODULE_LICENSE("GPL v2");
 228 MODULE_VERSION(UFSHCD_DRIVER_VERSION);