1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 Avionic Design GmbH 4 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved. 5 */ 6 7 #include <linux/clk.h> 8 9 #include <drm/drm_atomic_helper.h> 10 #include <drm/drm_bridge_connector.h> 11 #include <drm/drm_simple_kms_helper.h> 12 13 #include "drm.h" 14 #include "dc.h" 15 16 struct tegra_rgb { 17 struct tegra_output output; 18 struct tegra_dc *dc; 19 20 struct clk *clk_parent; 21 struct clk *clk; 22 }; 23 24 static inline struct tegra_rgb *to_rgb(struct tegra_output *output) 25 { 26 return container_of(output, struct tegra_rgb, output); 27 } 28 29 struct reg_entry { 30 unsigned long offset; 31 unsigned long value; 32 }; 33 34 static const struct reg_entry rgb_enable[] = { 35 { DC_COM_PIN_OUTPUT_ENABLE(0), 0x00000000 }, 36 { DC_COM_PIN_OUTPUT_ENABLE(1), 0x00000000 }, 37 { DC_COM_PIN_OUTPUT_ENABLE(2), 0x00000000 }, 38 { DC_COM_PIN_OUTPUT_ENABLE(3), 0x00000000 }, 39 { DC_COM_PIN_OUTPUT_POLARITY(0), 0x00000000 }, 40 { DC_COM_PIN_OUTPUT_POLARITY(1), 0x01000000 }, 41 { DC_COM_PIN_OUTPUT_POLARITY(2), 0x00000000 }, 42 { DC_COM_PIN_OUTPUT_POLARITY(3), 0x00000000 }, 43 { DC_COM_PIN_OUTPUT_DATA(0), 0x00000000 }, 44 { DC_COM_PIN_OUTPUT_DATA(1), 0x00000000 }, 45 { DC_COM_PIN_OUTPUT_DATA(2), 0x00000000 }, 46 { DC_COM_PIN_OUTPUT_DATA(3), 0x00000000 }, 47 { DC_COM_PIN_OUTPUT_SELECT(0), 0x00000000 }, 48 { DC_COM_PIN_OUTPUT_SELECT(1), 0x00000000 }, 49 { DC_COM_PIN_OUTPUT_SELECT(2), 0x00000000 }, 50 { DC_COM_PIN_OUTPUT_SELECT(3), 0x00000000 }, 51 { DC_COM_PIN_OUTPUT_SELECT(4), 0x00210222 }, 52 { DC_COM_PIN_OUTPUT_SELECT(5), 0x00002200 }, 53 { DC_COM_PIN_OUTPUT_SELECT(6), 0x00020000 }, 54 }; 55 56 static const struct reg_entry rgb_disable[] = { 57 { DC_COM_PIN_OUTPUT_SELECT(6), 0x00000000 }, 58 { DC_COM_PIN_OUTPUT_SELECT(5), 0x00000000 }, 59 { DC_COM_PIN_OUTPUT_SELECT(4), 0x00000000 }, 60 { DC_COM_PIN_OUTPUT_SELECT(3), 0x00000000 }, 61 { DC_COM_PIN_OUTPUT_SELECT(2), 0x00000000 }, 62 { DC_COM_PIN_OUTPUT_SELECT(1), 0x00000000 }, 63 { DC_COM_PIN_OUTPUT_SELECT(0), 0x00000000 }, 64 { DC_COM_PIN_OUTPUT_DATA(3), 0xaaaaaaaa }, 65 { DC_COM_PIN_OUTPUT_DATA(2), 0xaaaaaaaa }, 66 { DC_COM_PIN_OUTPUT_DATA(1), 0xaaaaaaaa }, 67 { DC_COM_PIN_OUTPUT_DATA(0), 0xaaaaaaaa }, 68 { DC_COM_PIN_OUTPUT_POLARITY(3), 0x00000000 }, 69 { DC_COM_PIN_OUTPUT_POLARITY(2), 0x00000000 }, 70 { DC_COM_PIN_OUTPUT_POLARITY(1), 0x00000000 }, 71 { DC_COM_PIN_OUTPUT_POLARITY(0), 0x00000000 }, 72 { DC_COM_PIN_OUTPUT_ENABLE(3), 0x55555555 }, 73 { DC_COM_PIN_OUTPUT_ENABLE(2), 0x55555555 }, 74 { DC_COM_PIN_OUTPUT_ENABLE(1), 0x55150005 }, 75 { DC_COM_PIN_OUTPUT_ENABLE(0), 0x55555555 }, 76 }; 77 78 static void tegra_dc_write_regs(struct tegra_dc *dc, 79 const struct reg_entry *table, 80 unsigned int num) 81 { 82 unsigned int i; 83 84 for (i = 0; i < num; i++) 85 tegra_dc_writel(dc, table[i].value, table[i].offset); 86 } 87 88 static void tegra_rgb_encoder_disable(struct drm_encoder *encoder) 89 { 90 struct tegra_output *output = encoder_to_output(encoder); 91 struct tegra_rgb *rgb = to_rgb(output); 92 93 tegra_dc_write_regs(rgb->dc, rgb_disable, ARRAY_SIZE(rgb_disable)); 94 tegra_dc_commit(rgb->dc); 95 } 96 97 static void tegra_rgb_encoder_enable(struct drm_encoder *encoder) 98 { 99 struct tegra_output *output = encoder_to_output(encoder); 100 struct tegra_rgb *rgb = to_rgb(output); 101 u32 value; 102 103 tegra_dc_write_regs(rgb->dc, rgb_enable, ARRAY_SIZE(rgb_enable)); 104 105 value = DE_SELECT_ACTIVE | DE_CONTROL_NORMAL; 106 tegra_dc_writel(rgb->dc, value, DC_DISP_DATA_ENABLE_OPTIONS); 107 108 /* XXX: parameterize? */ 109 value = tegra_dc_readl(rgb->dc, DC_COM_PIN_OUTPUT_POLARITY(1)); 110 value &= ~LVS_OUTPUT_POLARITY_LOW; 111 value &= ~LHS_OUTPUT_POLARITY_LOW; 112 tegra_dc_writel(rgb->dc, value, DC_COM_PIN_OUTPUT_POLARITY(1)); 113 114 /* XXX: parameterize? */ 115 value = DISP_DATA_FORMAT_DF1P1C | DISP_ALIGNMENT_MSB | 116 DISP_ORDER_RED_BLUE; 117 tegra_dc_writel(rgb->dc, value, DC_DISP_DISP_INTERFACE_CONTROL); 118 119 /* XXX: parameterize? */ 120 value = SC0_H_QUALIFIER_NONE | SC1_H_QUALIFIER_NONE; 121 tegra_dc_writel(rgb->dc, value, DC_DISP_SHIFT_CLOCK_OPTIONS); 122 123 tegra_dc_commit(rgb->dc); 124 } 125 126 static int 127 tegra_rgb_encoder_atomic_check(struct drm_encoder *encoder, 128 struct drm_crtc_state *crtc_state, 129 struct drm_connector_state *conn_state) 130 { 131 struct tegra_output *output = encoder_to_output(encoder); 132 struct tegra_dc *dc = to_tegra_dc(conn_state->crtc); 133 unsigned long pclk = crtc_state->mode.clock * 1000; 134 struct tegra_rgb *rgb = to_rgb(output); 135 unsigned int div; 136 int err; 137 138 /* 139 * We may not want to change the frequency of the parent clock, since 140 * it may be a parent for other peripherals. This is due to the fact 141 * that on Tegra20 there's only a single clock dedicated to display 142 * (pll_d_out0), whereas later generations have a second one that can 143 * be used to independently drive a second output (pll_d2_out0). 144 * 145 * As a way to support multiple outputs on Tegra20 as well, pll_p is 146 * typically used as the parent clock for the display controllers. 147 * But this comes at a cost: pll_p is the parent of several other 148 * peripherals, so its frequency shouldn't change out of the blue. 149 * 150 * The best we can do at this point is to use the shift clock divider 151 * and hope that the desired frequency can be matched (or at least 152 * matched sufficiently close that the panel will still work). 153 */ 154 div = ((clk_get_rate(rgb->clk) * 2) / pclk) - 2; 155 pclk = 0; 156 157 err = tegra_dc_state_setup_clock(dc, crtc_state, rgb->clk_parent, 158 pclk, div); 159 if (err < 0) { 160 dev_err(output->dev, "failed to setup CRTC state: %d\n", err); 161 return err; 162 } 163 164 return err; 165 } 166 167 static const struct drm_encoder_helper_funcs tegra_rgb_encoder_helper_funcs = { 168 .disable = tegra_rgb_encoder_disable, 169 .enable = tegra_rgb_encoder_enable, 170 .atomic_check = tegra_rgb_encoder_atomic_check, 171 }; 172 173 int tegra_dc_rgb_probe(struct tegra_dc *dc) 174 { 175 struct device_node *np; 176 struct tegra_rgb *rgb; 177 int err; 178 179 np = of_get_child_by_name(dc->dev->of_node, "rgb"); 180 if (!np || !of_device_is_available(np)) 181 return -ENODEV; 182 183 rgb = devm_kzalloc(dc->dev, sizeof(*rgb), GFP_KERNEL); 184 if (!rgb) 185 return -ENOMEM; 186 187 rgb->output.dev = dc->dev; 188 rgb->output.of_node = np; 189 rgb->dc = dc; 190 191 err = tegra_output_probe(&rgb->output); 192 if (err < 0) 193 return err; 194 195 rgb->clk = devm_clk_get(dc->dev, NULL); 196 if (IS_ERR(rgb->clk)) { 197 dev_err(dc->dev, "failed to get clock\n"); 198 return PTR_ERR(rgb->clk); 199 } 200 201 rgb->clk_parent = devm_clk_get(dc->dev, "parent"); 202 if (IS_ERR(rgb->clk_parent)) { 203 dev_err(dc->dev, "failed to get parent clock\n"); 204 return PTR_ERR(rgb->clk_parent); 205 } 206 207 err = clk_set_parent(rgb->clk, rgb->clk_parent); 208 if (err < 0) { 209 dev_err(dc->dev, "failed to set parent clock: %d\n", err); 210 return err; 211 } 212 213 dc->rgb = &rgb->output; 214 215 return 0; 216 } 217 218 int tegra_dc_rgb_remove(struct tegra_dc *dc) 219 { 220 if (!dc->rgb) 221 return 0; 222 223 tegra_output_remove(dc->rgb); 224 dc->rgb = NULL; 225 226 return 0; 227 } 228 229 int tegra_dc_rgb_init(struct drm_device *drm, struct tegra_dc *dc) 230 { 231 struct tegra_output *output = dc->rgb; 232 struct drm_connector *connector; 233 int err; 234 235 if (!dc->rgb) 236 return -ENODEV; 237 238 drm_simple_encoder_init(drm, &output->encoder, DRM_MODE_ENCODER_LVDS); 239 drm_encoder_helper_add(&output->encoder, 240 &tegra_rgb_encoder_helper_funcs); 241 242 /* 243 * Wrap directly-connected panel into DRM bridge in order to let 244 * DRM core to handle panel for us. 245 */ 246 if (output->panel) { 247 output->bridge = devm_drm_panel_bridge_add(output->dev, 248 output->panel); 249 if (IS_ERR(output->bridge)) { 250 dev_err(output->dev, 251 "failed to wrap panel into bridge: %pe\n", 252 output->bridge); 253 return PTR_ERR(output->bridge); 254 } 255 256 output->panel = NULL; 257 } 258 259 /* 260 * Tegra devices that have LVDS panel utilize LVDS encoder bridge 261 * for converting up to 28 LCD LVTTL lanes into 5/4 LVDS lanes that 262 * go to display panel's receiver. 263 * 264 * Encoder usually have a power-down control which needs to be enabled 265 * in order to transmit data to the panel. Historically devices that 266 * use an older device-tree version didn't model the bridge, assuming 267 * that encoder is turned ON by default, while today's DRM allows us 268 * to model LVDS encoder properly. 269 * 270 * Newer device-trees utilize LVDS encoder bridge, which provides 271 * us with a connector and handles the display panel. 272 * 273 * For older device-trees we wrapped panel into the panel-bridge. 274 */ 275 if (output->bridge) { 276 err = drm_bridge_attach(&output->encoder, output->bridge, 277 NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR); 278 if (err) { 279 dev_err(output->dev, "failed to attach bridge: %d\n", 280 err); 281 return err; 282 } 283 284 connector = drm_bridge_connector_init(drm, &output->encoder); 285 if (IS_ERR(connector)) { 286 dev_err(output->dev, 287 "failed to initialize bridge connector: %pe\n", 288 connector); 289 return PTR_ERR(connector); 290 } 291 292 drm_connector_attach_encoder(connector, &output->encoder); 293 } 294 295 err = tegra_output_init(drm, output); 296 if (err < 0) { 297 dev_err(output->dev, "failed to initialize output: %d\n", err); 298 return err; 299 } 300 301 /* 302 * Other outputs can be attached to either display controller. The RGB 303 * outputs are an exception and work only with their parent display 304 * controller. 305 */ 306 output->encoder.possible_crtcs = drm_crtc_mask(&dc->base); 307 308 return 0; 309 } 310 311 int tegra_dc_rgb_exit(struct tegra_dc *dc) 312 { 313 if (dc->rgb) 314 tegra_output_exit(dc->rgb); 315 316 return 0; 317 } 318