drivers/gpu/drm/msm/edp/edp_phy.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
   4  */
   5
   6 #include "edp.h"
   7 #include "edp.xml.h"
   8
   9 #define EDP_MAX_LANE    4
  10
  11 struct edp_phy {
  12         void __iomem *base;
  13 };
  14
  15 bool msm_edp_phy_ready(struct edp_phy *phy)
  16 {
  17         u32 status;
  18         int cnt = 100;
  19
  20         while (--cnt) {
  21                 status = edp_read(phy->base +
  22                                 REG_EDP_PHY_GLB_PHY_STATUS);
  23                 if (status & 0x01)
  24                         break;
  25                 usleep_range(500, 1000);
  26         }
  27
  28         if (cnt == 0) {
  29                 pr_err("%s: PHY NOT ready\n", __func__);
  30                 return false;
  31         } else {
  32                 return true;
  33         }
  34 }
  35
  36 void msm_edp_phy_ctrl(struct edp_phy *phy, int enable)
  37 {
  38         DBG("enable=%d", enable);
  39         if (enable) {
  40                 /* Reset */
  41                 edp_write(phy->base + REG_EDP_PHY_CTRL,
  42                         EDP_PHY_CTRL_SW_RESET | EDP_PHY_CTRL_SW_RESET_PLL);
  43                 /* Make sure fully reset */
  44                 wmb();
  45                 usleep_range(500, 1000);
  46                 edp_write(phy->base + REG_EDP_PHY_CTRL, 0x000);
  47                 edp_write(phy->base + REG_EDP_PHY_GLB_PD_CTL, 0x3f);
  48                 edp_write(phy->base + REG_EDP_PHY_GLB_CFG, 0x1);
  49         } else {
  50                 edp_write(phy->base + REG_EDP_PHY_GLB_PD_CTL, 0xc0);
  51         }
  52 }
  53
  54 /* voltage mode and pre emphasis cfg */
  55 void msm_edp_phy_vm_pe_init(struct edp_phy *phy)
  56 {
  57         edp_write(phy->base + REG_EDP_PHY_GLB_VM_CFG0, 0x3);
  58         edp_write(phy->base + REG_EDP_PHY_GLB_VM_CFG1, 0x64);
  59         edp_write(phy->base + REG_EDP_PHY_GLB_MISC9, 0x6c);
  60 }
  61
  62 void msm_edp_phy_vm_pe_cfg(struct edp_phy *phy, u32 v0, u32 v1)
  63 {
  64         edp_write(phy->base + REG_EDP_PHY_GLB_VM_CFG0, v0);
  65         edp_write(phy->base + REG_EDP_PHY_GLB_VM_CFG1, v1);
  66 }
  67
  68 void msm_edp_phy_lane_power_ctrl(struct edp_phy *phy, bool up, u32 max_lane)
  69 {
  70         u32 i;
  71         u32 data;
  72
  73         if (up)
  74                 data = 0;       /* power up */
  75         else
  76                 data = 0x7;     /* power down */
  77
  78         for (i = 0; i < max_lane; i++)
  79                 edp_write(phy->base + REG_EDP_PHY_LN_PD_CTL(i) , data);
  80
  81         /* power down unused lane */
  82         data = 0x7;     /* power down */
  83         for (i = max_lane; i < EDP_MAX_LANE; i++)
  84                 edp_write(phy->base + REG_EDP_PHY_LN_PD_CTL(i) , data);
  85 }
  86
  87 void *msm_edp_phy_init(struct device *dev, void __iomem *regbase)
  88 {
  89         struct edp_phy *phy = NULL;
  90
  91         phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
  92         if (!phy)
  93                 return NULL;
  94
  95         phy->base = regbase;
  96         return phy;
  97 }
  98