drivers/video/tegra.c

   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 int lcd_color_fg;
  65 int lcd_color_bg;
  66
  67 void *lcd_base;                 /* Start of framebuffer memory  */
  68 void *lcd_console_address;      /* Start of console buffer      */
  69
  70 short console_col;
  71 short console_row;
  72
  73 vidinfo_t panel_info = {
  74         /* Insert a value here so that we don't end up in the BSS */
  75         .vl_col = -1,
  76 };
  77
  78 char lcd_cursor_enabled;
  79
  80 ushort lcd_cursor_width;
  81 ushort lcd_cursor_height;
  82
  83 #ifndef CONFIG_OF_CONTROL
  84 #error "You must enable CONFIG_OF_CONTROL to get Tegra LCD support"
  85 #endif
  86
  87 void lcd_cursor_size(ushort width, ushort height)
  88 {
  89         lcd_cursor_width = width;
  90         lcd_cursor_height = height;
  91 }
  92
  93 void lcd_toggle_cursor(void)
  94 {
  95         ushort x, y;
  96         uchar *dest;
  97         ushort row;
  98
  99         x = console_col * lcd_cursor_width;
 100         y = console_row * lcd_cursor_height;
 101         dest = (uchar *)(lcd_base + y * lcd_line_length + x * (1 << LCD_BPP) /
 102                         8);
 103
 104         for (row = 0; row < lcd_cursor_height; ++row, dest += lcd_line_length) {
 105                 ushort *d = (ushort *)dest;
 106                 ushort color;
 107                 int i;
 108
 109                 for (i = 0; i < lcd_cursor_width; ++i) {
 110                         color = *d;
 111                         color ^= lcd_color_fg;
 112                         *d = color;
 113                         ++d;
 114                 }
 115         }
 116 }
 117
 118 void lcd_cursor_on(void)
 119 {
 120         lcd_cursor_enabled = 1;
 121         lcd_toggle_cursor();
 122 }
 123 void lcd_cursor_off(void)
 124 {
 125         lcd_cursor_enabled = 0;
 126         lcd_toggle_cursor();
 127 }
 128
 129 char lcd_is_cursor_enabled(void)
 130 {
 131         return lcd_cursor_enabled;
 132 }
 133
 134 static void update_panel_size(struct fdt_disp_config *config)
 135 {
 136         panel_info.vl_col = config->width;
 137         panel_info.vl_row = config->height;
 138         panel_info.vl_bpix = config->log2_bpp;
 139 }
 140
 141 /*
 142  *  Main init function called by lcd driver.
 143  *  Inits and then prints test pattern if required.
 144  */
 145
 146 void lcd_ctrl_init(void *lcdbase)
 147 {
 148         int line_length, size;
 149         int type = DCACHE_OFF;
 150
 151         assert(disp_config);
 152
 153         lcd_base = (void *)disp_config->frame_buffer;
 154
 155         /* Make sure that we can acommodate the selected LCD */
 156         assert(disp_config->width <= LCD_MAX_WIDTH);
 157         assert(disp_config->height <= LCD_MAX_HEIGHT);
 158         assert(disp_config->log2_bpp <= LCD_MAX_LOG2_BPP);
 159         if (disp_config->width <= LCD_MAX_WIDTH
 160                         && disp_config->height <= LCD_MAX_HEIGHT
 161                         && disp_config->log2_bpp <= LCD_MAX_LOG2_BPP)
 162                 update_panel_size(disp_config);
 163         size = lcd_get_size(&line_length);
 164
 165         /* Set up the LCD caching as requested */
 166         if (config.cache_type & FDT_LCD_CACHE_WRITE_THROUGH)
 167                 type = DCACHE_WRITETHROUGH;
 168         else if (config.cache_type & FDT_LCD_CACHE_WRITE_BACK)
 169                 type = DCACHE_WRITEBACK;
 170         mmu_set_region_dcache_behaviour(disp_config->frame_buffer, size, type);
 171
 172         /* Enable flushing after LCD writes if requested */
 173         lcd_set_flush_dcache(config.cache_type & FDT_LCD_CACHE_FLUSH);
 174
 175         debug("LCD frame buffer at %p\n", lcd_base);
 176 }
 177
 178 ulong calc_fbsize(void)
 179 {
 180         return (panel_info.vl_col * panel_info.vl_row *
 181                 NBITS(panel_info.vl_bpix)) / 8;
 182 }
 183
 184 void lcd_setcolreg(ushort regno, ushort red, ushort green, ushort blue)
 185 {
 186 }
 187
 188 void tegra_lcd_early_init(const void *blob)
 189 {
 190         /*
 191          * Go with the maximum size for now. We will fix this up after
 192          * relocation. These values are only used for memory alocation.
 193          */
 194         panel_info.vl_col = LCD_MAX_WIDTH;
 195         panel_info.vl_row = LCD_MAX_HEIGHT;
 196         panel_info.vl_bpix = LCD_MAX_LOG2_BPP;
 197 }
 198
 199 /**
 200  * Decode the panel information from the fdt.
 201  *
 202  * @param blob          fdt blob
 203  * @param config        structure to store fdt config into
 204  * @return 0 if ok, -ve on error
 205  */
 206 static int fdt_decode_lcd(const void *blob, struct fdt_panel_config *config)
 207 {
 208         int display_node;
 209
 210         disp_config = tegra_display_get_config();
 211         if (!disp_config) {
 212                 debug("%s: Display controller is not configured\n", __func__);
 213                 return -1;
 214         }
 215         display_node = disp_config->panel_node;
 216         if (display_node < 0) {
 217                 debug("%s: No panel configuration available\n", __func__);
 218                 return -1;
 219         }
 220
 221         config->pwm_channel = pwm_request(blob, display_node, "nvidia,pwm");
 222         if (config->pwm_channel < 0) {
 223                 debug("%s: Unable to request PWM channel\n", __func__);
 224                 return -1;
 225         }
 226
 227         config->cache_type = fdtdec_get_int(blob, display_node,
 228                                             "nvidia,cache-type",
 229                                             FDT_LCD_CACHE_WRITE_BACK_FLUSH);
 230
 231         /* These GPIOs are all optional */
 232         fdtdec_decode_gpio(blob, display_node, "nvidia,backlight-enable-gpios",
 233                             &config->backlight_en);
 234         fdtdec_decode_gpio(blob, display_node, "nvidia,lvds-shutdown-gpios",
 235                            &config->lvds_shutdown);
 236         fdtdec_decode_gpio(blob, display_node, "nvidia,backlight-vdd-gpios",
 237                            &config->backlight_vdd);
 238         fdtdec_decode_gpio(blob, display_node, "nvidia,panel-vdd-gpios",
 239                            &config->panel_vdd);
 240
 241         return fdtdec_get_int_array(blob, display_node, "nvidia,panel-timings",
 242                         config->panel_timings, FDT_LCD_TIMINGS);
 243 }
 244
 245 /**
 246  * Handle the next stage of device init
 247  */
 248 static int handle_stage(const void *blob)
 249 {
 250         debug("%s: stage %d\n", __func__, stage);
 251
 252         /* do the things for this stage */
 253         switch (stage) {
 254         case STAGE_START:
 255                 /* Initialize the Tegra display controller */
 256                 if (tegra_display_probe(gd->fdt_blob, (void *)gd->fb_base)) {
 257                         printf("%s: Failed to probe display driver\n",
 258                         __func__);
 259                         return -1;
 260                 }
 261
 262                 /* get panel details */
 263                 if (fdt_decode_lcd(blob, &config)) {
 264                         printf("No valid LCD information in device tree\n");
 265                         return -1;
 266                 }
 267
 268                 /*
 269                  * It is possible that the FDT has requested that the LCD be
 270                  * disabled. We currently don't support this. It would require
 271                  * changes to U-Boot LCD subsystem to have LCD support
 272                  * compiled in but not used. An easier option might be to
 273                  * still have a frame buffer, but leave the backlight off and
 274                  * remove all mention of lcd in the stdout environment
 275                  * variable.
 276                  */
 277
 278                 funcmux_select(PERIPH_ID_DISP1, FUNCMUX_DEFAULT);
 279
 280                 fdtdec_setup_gpio(&config.panel_vdd);
 281                 fdtdec_setup_gpio(&config.lvds_shutdown);
 282                 fdtdec_setup_gpio(&config.backlight_vdd);
 283                 fdtdec_setup_gpio(&config.backlight_en);
 284
 285                 /*
 286                  * TODO: If fdt includes output flag we can omit this code
 287                  * since fdtdec_setup_gpio will do it for us.
 288                  */
 289                 if (fdt_gpio_isvalid(&config.panel_vdd))
 290                         gpio_direction_output(config.panel_vdd.gpio, 0);
 291                 if (fdt_gpio_isvalid(&config.lvds_shutdown))
 292                         gpio_direction_output(config.lvds_shutdown.gpio, 0);
 293                 if (fdt_gpio_isvalid(&config.backlight_vdd))
 294                         gpio_direction_output(config.backlight_vdd.gpio, 0);
 295                 if (fdt_gpio_isvalid(&config.backlight_en))
 296                         gpio_direction_output(config.backlight_en.gpio, 0);
 297                 break;
 298         case STAGE_PANEL_VDD:
 299                 if (fdt_gpio_isvalid(&config.panel_vdd))
 300                         gpio_direction_output(config.panel_vdd.gpio, 1);
 301                 break;
 302         case STAGE_LVDS:
 303                 if (fdt_gpio_isvalid(&config.lvds_shutdown))
 304                         gpio_set_value(config.lvds_shutdown.gpio, 1);
 305                 break;
 306         case STAGE_BACKLIGHT_VDD:
 307                 if (fdt_gpio_isvalid(&config.backlight_vdd))
 308                         gpio_set_value(config.backlight_vdd.gpio, 1);
 309                 break;
 310         case STAGE_PWM:
 311                 /* Enable PWM at 15/16 high, 32768 Hz with divider 1 */
 312                 pinmux_set_func(PINGRP_GPU, PMUX_FUNC_PWM);
 313                 pinmux_tristate_disable(PINGRP_GPU);
 314
 315                 pwm_enable(config.pwm_channel, 32768, 0xdf, 1);
 316                 break;
 317         case STAGE_BACKLIGHT_EN:
 318                 if (fdt_gpio_isvalid(&config.backlight_en))
 319                         gpio_set_value(config.backlight_en.gpio, 1);
 320                 break;
 321         case STAGE_DONE:
 322                 break;
 323         }
 324
 325         /* set up timer for next stage */
 326         timer_next = timer_get_us();
 327         if (stage < FDT_LCD_TIMINGS)
 328                 timer_next += config.panel_timings[stage] * 1000;
 329
 330         /* move to next stage */
 331         stage++;
 332         return 0;
 333 }
 334
 335 int tegra_lcd_check_next_stage(const void *blob, int wait)
 336 {
 337         if (stage == STAGE_DONE)
 338                 return 0;
 339
 340         do {
 341                 /* wait if we need to */
 342                 debug("%s: stage %d\n", __func__, stage);
 343                 if (stage != STAGE_START) {
 344                         int delay = timer_next - timer_get_us();
 345
 346                         if (delay > 0) {
 347                                 if (wait)
 348                                         udelay(delay);
 349                                 else
 350                                         return 0;
 351                         }
 352                 }
 353
 354                 if (handle_stage(blob))
 355                         return -1;
 356         } while (wait && stage != STAGE_DONE);
 357         if (stage == STAGE_DONE)
 358                 debug("%s: LCD init complete\n", __func__);
 359
 360         return 0;
 361 }
 362
 363 void lcd_enable(void)
 364 {
 365         /*
 366          * Backlight and power init will be done separately in
 367          * tegra_lcd_check_next_stage(), which should be called in
 368          * board_late_init().
 369          *
 370          * U-Boot code supports only colour depth, selected at compile time.
 371          * The device tree setting should match this. Otherwise the display
 372          * will not look right, and U-Boot may crash.
 373          */
 374         if (disp_config->log2_bpp != LCD_BPP) {
 375                 printf("%s: Error: LCD depth configured in FDT (%d = %dbpp)"
 376                         " must match setting of LCD_BPP (%d)\n", __func__,
 377                        disp_config->log2_bpp, disp_config->bpp, LCD_BPP);
 378         }
 379 }