2 * Copyright (c) 2011 The Chromium OS Authors.
3 * See file CREDITS for list of people who contributed to this
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.
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.
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,
26 #include <asm/system.h>
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>
36 DECLARE_GLOBAL_DATA_PTR;
38 /* These are the stages we go throuh in enabling the LCD */
49 static enum stage_t stage; /* Current stage we are at */
50 static unsigned long timer_next; /* Time we can move onto next stage */
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 */
57 /* Maximum LCD size we support */
60 LCD_MAX_LOG2_BPP = 4, /* 2^4 = 16 bpp */
63 vidinfo_t panel_info = {
64 /* Insert a value here so that we don't end up in the BSS */
68 #ifndef CONFIG_OF_CONTROL
69 #error "You must enable CONFIG_OF_CONTROL to get Tegra LCD support"
72 static void update_panel_size(struct fdt_disp_config *config)
74 panel_info.vl_col = config->width;
75 panel_info.vl_row = config->height;
76 panel_info.vl_bpix = config->log2_bpp;
80 * Main init function called by lcd driver.
81 * Inits and then prints test pattern if required.
84 void lcd_ctrl_init(void *lcdbase)
86 int type = DCACHE_OFF;
91 /* Make sure that we can acommodate the selected LCD */
92 assert(disp_config->width <= LCD_MAX_WIDTH);
93 assert(disp_config->height <= LCD_MAX_HEIGHT);
94 assert(disp_config->log2_bpp <= LCD_MAX_LOG2_BPP);
95 if (disp_config->width <= LCD_MAX_WIDTH
96 && disp_config->height <= LCD_MAX_HEIGHT
97 && disp_config->log2_bpp <= LCD_MAX_LOG2_BPP)
98 update_panel_size(disp_config);
99 size = lcd_get_size(&lcd_line_length);
101 /* Set up the LCD caching as requested */
102 if (config.cache_type & FDT_LCD_CACHE_WRITE_THROUGH)
103 type = DCACHE_WRITETHROUGH;
104 else if (config.cache_type & FDT_LCD_CACHE_WRITE_BACK)
105 type = DCACHE_WRITEBACK;
106 mmu_set_region_dcache_behaviour(disp_config->frame_buffer, size, type);
108 /* Enable flushing after LCD writes if requested */
109 lcd_set_flush_dcache(config.cache_type & FDT_LCD_CACHE_FLUSH);
111 debug("LCD frame buffer at %08X\n", disp_config->frame_buffer);
114 ulong calc_fbsize(void)
116 return (panel_info.vl_col * panel_info.vl_row *
117 NBITS(panel_info.vl_bpix)) / 8;
120 void lcd_setcolreg(ushort regno, ushort red, ushort green, ushort blue)
124 void tegra_lcd_early_init(const void *blob)
127 * Go with the maximum size for now. We will fix this up after
128 * relocation. These values are only used for memory alocation.
130 panel_info.vl_col = LCD_MAX_WIDTH;
131 panel_info.vl_row = LCD_MAX_HEIGHT;
132 panel_info.vl_bpix = LCD_MAX_LOG2_BPP;
136 * Decode the panel information from the fdt.
138 * @param blob fdt blob
139 * @param config structure to store fdt config into
140 * @return 0 if ok, -ve on error
142 static int fdt_decode_lcd(const void *blob, struct fdt_panel_config *config)
146 disp_config = tegra_display_get_config();
148 debug("%s: Display controller is not configured\n", __func__);
151 display_node = disp_config->panel_node;
152 if (display_node < 0) {
153 debug("%s: No panel configuration available\n", __func__);
157 config->pwm_channel = pwm_request(blob, display_node, "nvidia,pwm");
158 if (config->pwm_channel < 0) {
159 debug("%s: Unable to request PWM channel\n", __func__);
163 config->cache_type = fdtdec_get_int(blob, display_node,
165 FDT_LCD_CACHE_WRITE_BACK_FLUSH);
167 /* These GPIOs are all optional */
168 fdtdec_decode_gpio(blob, display_node, "nvidia,backlight-enable-gpios",
169 &config->backlight_en);
170 fdtdec_decode_gpio(blob, display_node, "nvidia,lvds-shutdown-gpios",
171 &config->lvds_shutdown);
172 fdtdec_decode_gpio(blob, display_node, "nvidia,backlight-vdd-gpios",
173 &config->backlight_vdd);
174 fdtdec_decode_gpio(blob, display_node, "nvidia,panel-vdd-gpios",
177 return fdtdec_get_int_array(blob, display_node, "nvidia,panel-timings",
178 config->panel_timings, FDT_LCD_TIMINGS);
182 * Handle the next stage of device init
184 static int handle_stage(const void *blob)
186 debug("%s: stage %d\n", __func__, stage);
188 /* do the things for this stage */
191 /* Initialize the Tegra display controller */
192 if (tegra_display_probe(gd->fdt_blob, (void *)gd->fb_base)) {
193 printf("%s: Failed to probe display driver\n",
198 /* get panel details */
199 if (fdt_decode_lcd(blob, &config)) {
200 printf("No valid LCD information in device tree\n");
205 * It is possible that the FDT has requested that the LCD be
206 * disabled. We currently don't support this. It would require
207 * changes to U-Boot LCD subsystem to have LCD support
208 * compiled in but not used. An easier option might be to
209 * still have a frame buffer, but leave the backlight off and
210 * remove all mention of lcd in the stdout environment
214 funcmux_select(PERIPH_ID_DISP1, FUNCMUX_DEFAULT);
216 fdtdec_setup_gpio(&config.panel_vdd);
217 fdtdec_setup_gpio(&config.lvds_shutdown);
218 fdtdec_setup_gpio(&config.backlight_vdd);
219 fdtdec_setup_gpio(&config.backlight_en);
222 * TODO: If fdt includes output flag we can omit this code
223 * since fdtdec_setup_gpio will do it for us.
225 if (fdt_gpio_isvalid(&config.panel_vdd))
226 gpio_direction_output(config.panel_vdd.gpio, 0);
227 if (fdt_gpio_isvalid(&config.lvds_shutdown))
228 gpio_direction_output(config.lvds_shutdown.gpio, 0);
229 if (fdt_gpio_isvalid(&config.backlight_vdd))
230 gpio_direction_output(config.backlight_vdd.gpio, 0);
231 if (fdt_gpio_isvalid(&config.backlight_en))
232 gpio_direction_output(config.backlight_en.gpio, 0);
234 case STAGE_PANEL_VDD:
235 if (fdt_gpio_isvalid(&config.panel_vdd))
236 gpio_direction_output(config.panel_vdd.gpio, 1);
239 if (fdt_gpio_isvalid(&config.lvds_shutdown))
240 gpio_set_value(config.lvds_shutdown.gpio, 1);
242 case STAGE_BACKLIGHT_VDD:
243 if (fdt_gpio_isvalid(&config.backlight_vdd))
244 gpio_set_value(config.backlight_vdd.gpio, 1);
247 /* Enable PWM at 15/16 high, 32768 Hz with divider 1 */
248 pinmux_set_func(PINGRP_GPU, PMUX_FUNC_PWM);
249 pinmux_tristate_disable(PINGRP_GPU);
251 pwm_enable(config.pwm_channel, 32768, 0xdf, 1);
253 case STAGE_BACKLIGHT_EN:
254 if (fdt_gpio_isvalid(&config.backlight_en))
255 gpio_set_value(config.backlight_en.gpio, 1);
261 /* set up timer for next stage */
262 timer_next = timer_get_us();
263 if (stage < FDT_LCD_TIMINGS)
264 timer_next += config.panel_timings[stage] * 1000;
266 /* move to next stage */
271 int tegra_lcd_check_next_stage(const void *blob, int wait)
273 if (stage == STAGE_DONE)
277 /* wait if we need to */
278 debug("%s: stage %d\n", __func__, stage);
279 if (stage != STAGE_START) {
280 int delay = timer_next - timer_get_us();
290 if (handle_stage(blob))
292 } while (wait && stage != STAGE_DONE);
293 if (stage == STAGE_DONE)
294 debug("%s: LCD init complete\n", __func__);
299 void lcd_enable(void)
302 * Backlight and power init will be done separately in
303 * tegra_lcd_check_next_stage(), which should be called in
306 * U-Boot code supports only colour depth, selected at compile time.
307 * The device tree setting should match this. Otherwise the display
308 * will not look right, and U-Boot may crash.
310 if (disp_config->log2_bpp != LCD_BPP) {
311 printf("%s: Error: LCD depth configured in FDT (%d = %dbpp)"
312 " must match setting of LCD_BPP (%d)\n", __func__,
313 disp_config->log2_bpp, disp_config->bpp, LCD_BPP);