drivers/gpu/drm/sti/sti_vtac.c

   1 /*
   2  * Copyright (C) STMicroelectronics SA 2014
   3  * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
   4  * License terms:  GNU General Public License (GPL), version 2
   5  */
   6
   7 #include <linux/clk.h>
   8 #include <linux/io.h>
   9 #include <linux/module.h>
  10 #include <linux/of.h>
  11 #include <linux/platform_device.h>
  12
  13 #include <drm/drmP.h>
  14
  15 #include "sti_drv.h"
  16
  17 /* registers offset */
  18 #define VTAC_CONFIG                     0x00
  19 #define VTAC_RX_FIFO_CONFIG             0x04
  20 #define VTAC_FIFO_CONFIG_VAL            0x04
  21
  22 #define VTAC_SYS_CFG8521                0x824
  23 #define VTAC_SYS_CFG8522                0x828
  24
  25 /* Number of phyts per pixel */
  26 #define VTAC_2_5_PPP                    0x0005
  27 #define VTAC_3_PPP                      0x0006
  28 #define VTAC_4_PPP                      0x0008
  29 #define VTAC_5_PPP                      0x000A
  30 #define VTAC_6_PPP                      0x000C
  31 #define VTAC_13_PPP                     0x001A
  32 #define VTAC_14_PPP                     0x001C
  33 #define VTAC_15_PPP                     0x001E
  34 #define VTAC_16_PPP                     0x0020
  35 #define VTAC_17_PPP                     0x0022
  36 #define VTAC_18_PPP                     0x0024
  37
  38 /* enable bits */
  39 #define VTAC_ENABLE                     0x3003
  40
  41 #define VTAC_TX_PHY_ENABLE_CLK_PHY      BIT(0)
  42 #define VTAC_TX_PHY_ENABLE_CLK_DLL      BIT(1)
  43 #define VTAC_TX_PHY_PLL_NOT_OSC_MODE    BIT(3)
  44 #define VTAC_TX_PHY_RST_N_DLL_SWITCH    BIT(4)
  45 #define VTAC_TX_PHY_PROG_N3             BIT(9)
  46
  47
  48 /**
  49  * VTAC mode structure
  50  *
  51  * @vid_in_width: Video Data Resolution
  52  * @phyts_width: Width of phyt buses(phyt low and phyt high).
  53  * @phyts_per_pixel: Number of phyts sent per pixel
  54  */
  55 struct sti_vtac_mode {
  56         u32 vid_in_width;
  57         u32 phyts_width;
  58         u32 phyts_per_pixel;
  59 };
  60
  61 static const struct sti_vtac_mode vtac_mode_main = {
  62         .vid_in_width = 0x2,
  63         .phyts_width = 0x2,
  64         .phyts_per_pixel = VTAC_5_PPP,
  65 };
  66 static const struct sti_vtac_mode vtac_mode_aux = {
  67         .vid_in_width = 0x1,
  68         .phyts_width = 0x0,
  69         .phyts_per_pixel = VTAC_17_PPP,
  70 };
  71
  72 /**
  73  * VTAC structure
  74  *
  75  * @dev: pointer to device structure
  76  * @regs: ioremapped registers for RX and TX devices
  77  * @phy_regs: phy registers for TX device
  78  * @clk: clock
  79  * @mode: main or auxillary configuration mode
  80  */
  81 struct sti_vtac {
  82         struct device *dev;
  83         void __iomem *regs;
  84         void __iomem *phy_regs;
  85         struct clk *clk;
  86         const struct sti_vtac_mode *mode;
  87 };
  88
  89 static void sti_vtac_rx_set_config(struct sti_vtac *vtac)
  90 {
  91         u32 config;
  92
  93         /* Enable VTAC clock */
  94         if (clk_prepare_enable(vtac->clk))
  95                 DRM_ERROR("Failed to prepare/enable vtac_rx clock.\n");
  96
  97         writel(VTAC_FIFO_CONFIG_VAL, vtac->regs + VTAC_RX_FIFO_CONFIG);
  98
  99         config = VTAC_ENABLE;
 100         config |= vtac->mode->vid_in_width << 4;
 101         config |= vtac->mode->phyts_width << 16;
 102         config |= vtac->mode->phyts_per_pixel << 23;
 103         writel(config, vtac->regs + VTAC_CONFIG);
 104 }
 105
 106 static void sti_vtac_tx_set_config(struct sti_vtac *vtac)
 107 {
 108         u32 phy_config;
 109         u32 config;
 110
 111         /* Enable VTAC clock */
 112         if (clk_prepare_enable(vtac->clk))
 113                 DRM_ERROR("Failed to prepare/enable vtac_tx clock.\n");
 114
 115         /* Configure vtac phy */
 116         phy_config = 0x00000000;
 117         writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8522);
 118         phy_config = VTAC_TX_PHY_ENABLE_CLK_PHY;
 119         writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
 120         phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
 121         phy_config |= VTAC_TX_PHY_PROG_N3;
 122         writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
 123         phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
 124         phy_config |= VTAC_TX_PHY_ENABLE_CLK_DLL;
 125         writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
 126         phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
 127         phy_config |= VTAC_TX_PHY_RST_N_DLL_SWITCH;
 128         writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
 129         phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
 130         phy_config |= VTAC_TX_PHY_PLL_NOT_OSC_MODE;
 131         writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
 132
 133         /* Configure vtac tx */
 134         config = VTAC_ENABLE;
 135         config |= vtac->mode->vid_in_width << 4;
 136         config |= vtac->mode->phyts_width << 16;
 137         config |= vtac->mode->phyts_per_pixel << 23;
 138         writel(config, vtac->regs + VTAC_CONFIG);
 139 }
 140
 141 static const struct of_device_id vtac_of_match[] = {
 142         {
 143                 .compatible = "st,vtac-main",
 144                 .data = &vtac_mode_main,
 145         }, {
 146                 .compatible = "st,vtac-aux",
 147                 .data = &vtac_mode_aux,
 148         }, {
 149                 /* end node */
 150         }
 151 };
 152 MODULE_DEVICE_TABLE(of, vtac_of_match);
 153
 154 static int sti_vtac_probe(struct platform_device *pdev)
 155 {
 156         struct device *dev = &pdev->dev;
 157         struct device_node *np = dev->of_node;
 158         const struct of_device_id *id;
 159         struct sti_vtac *vtac;
 160         struct resource *res;
 161
 162         vtac = devm_kzalloc(dev, sizeof(*vtac), GFP_KERNEL);
 163         if (!vtac)
 164                 return -ENOMEM;
 165
 166         vtac->dev = dev;
 167
 168         id = of_match_node(vtac_of_match, np);
 169         if (!id)
 170                 return -ENOMEM;
 171
 172         vtac->mode = id->data;
 173
 174         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 175         if (!res) {
 176                 DRM_ERROR("Invalid resource\n");
 177                 return -ENOMEM;
 178         }
 179         vtac->regs = devm_ioremap_resource(dev, res);
 180         if (IS_ERR(vtac->regs))
 181                 return PTR_ERR(vtac->regs);
 182
 183
 184         vtac->clk = devm_clk_get(dev, "vtac");
 185         if (IS_ERR(vtac->clk)) {
 186                 DRM_ERROR("Cannot get vtac clock\n");
 187                 return PTR_ERR(vtac->clk);
 188         }
 189
 190         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 191         if (res) {
 192                 vtac->phy_regs = devm_ioremap_nocache(dev, res->start,
 193                                                  resource_size(res));
 194                 sti_vtac_tx_set_config(vtac);
 195         } else {
 196
 197                 sti_vtac_rx_set_config(vtac);
 198         }
 199
 200         platform_set_drvdata(pdev, vtac);
 201         DRM_INFO("%s %s\n", __func__, dev_name(vtac->dev));
 202
 203         return 0;
 204 }
 205
 206 static int sti_vtac_remove(struct platform_device *pdev)
 207 {
 208         return 0;
 209 }
 210
 211 struct platform_driver sti_vtac_driver = {
 212         .driver = {
 213                 .name = "sti-vtac",
 214                 .owner = THIS_MODULE,
 215                 .of_match_table = vtac_of_match,
 216         },
 217         .probe = sti_vtac_probe,
 218         .remove = sti_vtac_remove,
 219 };
 220
 221 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 222 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 223 MODULE_LICENSE("GPL");