1 /* 2 * Copyright (c) 2011 The Chromium OS Authors. 3 * See file CREDITS for list of people who contributed to this 4 * project. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 19 * MA 02111-1307 USA 20 */ 21 22 #include <common.h> 23 #include <fdtdec.h> 24 #include <lcd.h> 25 26 #include <asm/system.h> 27 #include <asm/gpio.h> 28 29 #include <asm/arch/clock.h> 30 #include <asm/arch/funcmux.h> 31 #include <asm/arch/pinmux.h> 32 #include <asm/arch/pwm.h> 33 #include <asm/arch/display.h> 34 #include <asm/arch-tegra/timer.h> 35 36 DECLARE_GLOBAL_DATA_PTR; 37 38 /* These are the stages we go throuh in enabling the LCD */ 39 enum stage_t { 40 STAGE_START, 41 STAGE_PANEL_VDD, 42 STAGE_LVDS, 43 STAGE_BACKLIGHT_VDD, 44 STAGE_PWM, 45 STAGE_BACKLIGHT_EN, 46 STAGE_DONE, 47 }; 48 49 static enum stage_t stage; /* Current stage we are at */ 50 static unsigned long timer_next; /* Time we can move onto next stage */ 51 52 /* Our LCD config, set up in handle_stage() */ 53 static struct fdt_panel_config config; 54 struct fdt_disp_config *disp_config; /* Display controller config */ 55 56 enum { 57 /* Maximum LCD size we support */ 58 LCD_MAX_WIDTH = 1366, 59 LCD_MAX_HEIGHT = 768, 60 LCD_MAX_LOG2_BPP = 4, /* 2^4 = 16 bpp */ 61 }; 62 63 int lcd_line_length; 64 65 void *lcd_base; /* Start of framebuffer memory */ 66 void *lcd_console_address; /* Start of console buffer */ 67 68 short console_col; 69 short console_row; 70 71 vidinfo_t panel_info = { 72 /* Insert a value here so that we don't end up in the BSS */ 73 .vl_col = -1, 74 }; 75 76 #ifndef CONFIG_OF_CONTROL 77 #error "You must enable CONFIG_OF_CONTROL to get Tegra LCD support" 78 #endif 79 80 static void update_panel_size(struct fdt_disp_config *config) 81 { 82 panel_info.vl_col = config->width; 83 panel_info.vl_row = config->height; 84 panel_info.vl_bpix = config->log2_bpp; 85 } 86 87 /* 88 * Main init function called by lcd driver. 89 * Inits and then prints test pattern if required. 90 */ 91 92 void lcd_ctrl_init(void *lcdbase) 93 { 94 int type = DCACHE_OFF; 95 int size; 96 97 assert(disp_config); 98 99 lcd_base = (void *)disp_config->frame_buffer; 100 101 /* Make sure that we can acommodate the selected LCD */ 102 assert(disp_config->width <= LCD_MAX_WIDTH); 103 assert(disp_config->height <= LCD_MAX_HEIGHT); 104 assert(disp_config->log2_bpp <= LCD_MAX_LOG2_BPP); 105 if (disp_config->width <= LCD_MAX_WIDTH 106 && disp_config->height <= LCD_MAX_HEIGHT 107 && disp_config->log2_bpp <= LCD_MAX_LOG2_BPP) 108 update_panel_size(disp_config); 109 size = lcd_get_size(&lcd_line_length); 110 111 /* Set up the LCD caching as requested */ 112 if (config.cache_type & FDT_LCD_CACHE_WRITE_THROUGH) 113 type = DCACHE_WRITETHROUGH; 114 else if (config.cache_type & FDT_LCD_CACHE_WRITE_BACK) 115 type = DCACHE_WRITEBACK; 116 mmu_set_region_dcache_behaviour(disp_config->frame_buffer, size, type); 117 118 /* Enable flushing after LCD writes if requested */ 119 lcd_set_flush_dcache(config.cache_type & FDT_LCD_CACHE_FLUSH); 120 121 debug("LCD frame buffer at %p\n", lcd_base); 122 } 123 124 ulong calc_fbsize(void) 125 { 126 return (panel_info.vl_col * panel_info.vl_row * 127 NBITS(panel_info.vl_bpix)) / 8; 128 } 129 130 void lcd_setcolreg(ushort regno, ushort red, ushort green, ushort blue) 131 { 132 } 133 134 void tegra_lcd_early_init(const void *blob) 135 { 136 /* 137 * Go with the maximum size for now. We will fix this up after 138 * relocation. These values are only used for memory alocation. 139 */ 140 panel_info.vl_col = LCD_MAX_WIDTH; 141 panel_info.vl_row = LCD_MAX_HEIGHT; 142 panel_info.vl_bpix = LCD_MAX_LOG2_BPP; 143 } 144 145 /** 146 * Decode the panel information from the fdt. 147 * 148 * @param blob fdt blob 149 * @param config structure to store fdt config into 150 * @return 0 if ok, -ve on error 151 */ 152 static int fdt_decode_lcd(const void *blob, struct fdt_panel_config *config) 153 { 154 int display_node; 155 156 disp_config = tegra_display_get_config(); 157 if (!disp_config) { 158 debug("%s: Display controller is not configured\n", __func__); 159 return -1; 160 } 161 display_node = disp_config->panel_node; 162 if (display_node < 0) { 163 debug("%s: No panel configuration available\n", __func__); 164 return -1; 165 } 166 167 config->pwm_channel = pwm_request(blob, display_node, "nvidia,pwm"); 168 if (config->pwm_channel < 0) { 169 debug("%s: Unable to request PWM channel\n", __func__); 170 return -1; 171 } 172 173 config->cache_type = fdtdec_get_int(blob, display_node, 174 "nvidia,cache-type", 175 FDT_LCD_CACHE_WRITE_BACK_FLUSH); 176 177 /* These GPIOs are all optional */ 178 fdtdec_decode_gpio(blob, display_node, "nvidia,backlight-enable-gpios", 179 &config->backlight_en); 180 fdtdec_decode_gpio(blob, display_node, "nvidia,lvds-shutdown-gpios", 181 &config->lvds_shutdown); 182 fdtdec_decode_gpio(blob, display_node, "nvidia,backlight-vdd-gpios", 183 &config->backlight_vdd); 184 fdtdec_decode_gpio(blob, display_node, "nvidia,panel-vdd-gpios", 185 &config->panel_vdd); 186 187 return fdtdec_get_int_array(blob, display_node, "nvidia,panel-timings", 188 config->panel_timings, FDT_LCD_TIMINGS); 189 } 190 191 /** 192 * Handle the next stage of device init 193 */ 194 static int handle_stage(const void *blob) 195 { 196 debug("%s: stage %d\n", __func__, stage); 197 198 /* do the things for this stage */ 199 switch (stage) { 200 case STAGE_START: 201 /* Initialize the Tegra display controller */ 202 if (tegra_display_probe(gd->fdt_blob, (void *)gd->fb_base)) { 203 printf("%s: Failed to probe display driver\n", 204 __func__); 205 return -1; 206 } 207 208 /* get panel details */ 209 if (fdt_decode_lcd(blob, &config)) { 210 printf("No valid LCD information in device tree\n"); 211 return -1; 212 } 213 214 /* 215 * It is possible that the FDT has requested that the LCD be 216 * disabled. We currently don't support this. It would require 217 * changes to U-Boot LCD subsystem to have LCD support 218 * compiled in but not used. An easier option might be to 219 * still have a frame buffer, but leave the backlight off and 220 * remove all mention of lcd in the stdout environment 221 * variable. 222 */ 223 224 funcmux_select(PERIPH_ID_DISP1, FUNCMUX_DEFAULT); 225 226 fdtdec_setup_gpio(&config.panel_vdd); 227 fdtdec_setup_gpio(&config.lvds_shutdown); 228 fdtdec_setup_gpio(&config.backlight_vdd); 229 fdtdec_setup_gpio(&config.backlight_en); 230 231 /* 232 * TODO: If fdt includes output flag we can omit this code 233 * since fdtdec_setup_gpio will do it for us. 234 */ 235 if (fdt_gpio_isvalid(&config.panel_vdd)) 236 gpio_direction_output(config.panel_vdd.gpio, 0); 237 if (fdt_gpio_isvalid(&config.lvds_shutdown)) 238 gpio_direction_output(config.lvds_shutdown.gpio, 0); 239 if (fdt_gpio_isvalid(&config.backlight_vdd)) 240 gpio_direction_output(config.backlight_vdd.gpio, 0); 241 if (fdt_gpio_isvalid(&config.backlight_en)) 242 gpio_direction_output(config.backlight_en.gpio, 0); 243 break; 244 case STAGE_PANEL_VDD: 245 if (fdt_gpio_isvalid(&config.panel_vdd)) 246 gpio_direction_output(config.panel_vdd.gpio, 1); 247 break; 248 case STAGE_LVDS: 249 if (fdt_gpio_isvalid(&config.lvds_shutdown)) 250 gpio_set_value(config.lvds_shutdown.gpio, 1); 251 break; 252 case STAGE_BACKLIGHT_VDD: 253 if (fdt_gpio_isvalid(&config.backlight_vdd)) 254 gpio_set_value(config.backlight_vdd.gpio, 1); 255 break; 256 case STAGE_PWM: 257 /* Enable PWM at 15/16 high, 32768 Hz with divider 1 */ 258 pinmux_set_func(PINGRP_GPU, PMUX_FUNC_PWM); 259 pinmux_tristate_disable(PINGRP_GPU); 260 261 pwm_enable(config.pwm_channel, 32768, 0xdf, 1); 262 break; 263 case STAGE_BACKLIGHT_EN: 264 if (fdt_gpio_isvalid(&config.backlight_en)) 265 gpio_set_value(config.backlight_en.gpio, 1); 266 break; 267 case STAGE_DONE: 268 break; 269 } 270 271 /* set up timer for next stage */ 272 timer_next = timer_get_us(); 273 if (stage < FDT_LCD_TIMINGS) 274 timer_next += config.panel_timings[stage] * 1000; 275 276 /* move to next stage */ 277 stage++; 278 return 0; 279 } 280 281 int tegra_lcd_check_next_stage(const void *blob, int wait) 282 { 283 if (stage == STAGE_DONE) 284 return 0; 285 286 do { 287 /* wait if we need to */ 288 debug("%s: stage %d\n", __func__, stage); 289 if (stage != STAGE_START) { 290 int delay = timer_next - timer_get_us(); 291 292 if (delay > 0) { 293 if (wait) 294 udelay(delay); 295 else 296 return 0; 297 } 298 } 299 300 if (handle_stage(blob)) 301 return -1; 302 } while (wait && stage != STAGE_DONE); 303 if (stage == STAGE_DONE) 304 debug("%s: LCD init complete\n", __func__); 305 306 return 0; 307 } 308 309 void lcd_enable(void) 310 { 311 /* 312 * Backlight and power init will be done separately in 313 * tegra_lcd_check_next_stage(), which should be called in 314 * board_late_init(). 315 * 316 * U-Boot code supports only colour depth, selected at compile time. 317 * The device tree setting should match this. Otherwise the display 318 * will not look right, and U-Boot may crash. 319 */ 320 if (disp_config->log2_bpp != LCD_BPP) { 321 printf("%s: Error: LCD depth configured in FDT (%d = %dbpp)" 322 " must match setting of LCD_BPP (%d)\n", __func__, 323 disp_config->log2_bpp, disp_config->bpp, LCD_BPP); 324 } 325 } 326