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platform: mtk8937
以下为开机后调用关系：
根据不同的平台，这个函数所在的文件不同; 我们项目属于msm8952系列；
void target_display_init(const char *panel_name)
{struct oem_panel_data oem;int32_t ret = 0;uint32_t panel_loop = 0;set_panel_cmd_string(panel_name);oem = mdss_dsi_get_oem_data();if (!strcmp(oem.panel, NO_PANEL_CONFIG)|| !strcmp(oem.panel, SIM_VIDEO_PANEL)|| !strcmp(oem.panel, SIM_CMD_PANEL)|| oem.skip) {dprintf(INFO, "Selected panel: %s\nSkip panel configuration\n",oem.panel);return;}do {target_force_cont_splash_disable(false);ret = gcdb_display_init(oem.panel, MDP_REV_50, (void *)MIPI_FB_ADDR);if (!ret || ret == ERR_NOT_SUPPORTED) {break;} else {target_force_cont_splash_disable(true);msm_display_off();}} while (++panel_loop <= oem_panel_max_auto_detect_panels());if (!oem.cont_splash) {dprintf(INFO, "Forcing continuous splash disable\n");target_force_cont_splash_disable(true);}
}
再调用以下函数：
int gcdb_display_init(const char *panel_name, uint32_t rev, void *base)
{int ret = NO_ERROR;int pan_type;dsi_video_mode_phy_db.pll_type = DSI_PLL_TYPE_28NM;pan_type = oem_panel_select(panel_name, &panelstruct, &(panel.panel_info),&dsi_video_mode_phy_db);if (pan_type == PANEL_TYPE_DSI) {if (update_dsi_display_config())goto error_gcdb_display_init;target_dsi_phy_config(&dsi_video_mode_phy_db);mdss_dsi_check_swap_status();mdss_dsi_set_pll_src();if (dsi_panel_init(&(panel.panel_info), &panelstruct)) {dprintf(CRITICAL, "DSI panel init failed!\n");ret = ERROR;goto error_gcdb_display_init;}panel.panel_info.mipi.mdss_dsi_phy_db = &dsi_video_mode_phy_db;panel.pll_clk_func = mdss_dsi_panel_clock;panel.dfps_func = mdss_dsi_mipi_dfps_config;panel.power_func = mdss_dsi_panel_power;panel.pre_init_func = mdss_dsi_panel_pre_init;panel.bl_func = mdss_dsi_bl_enable;panel.dsi2HDMI_config = mdss_dsi2HDMI_config;/** Reserve fb memory to store pll codes and pass* pll codes values to kernel.*/panel.panel_info.dfps.dfps_fb_base = base;base += DFPS_PLL_CODES_SIZE;panel.fb.base = base;dprintf(SPEW, "dfps base=0x%p,d, fb_base=0x%p!\n",panel.panel_info.dfps.dfps_fb_base, base);panel.fb.width = panel.panel_info.xres;panel.fb.height = panel.panel_info.yres;panel.fb.stride = panel.panel_info.xres;panel.fb.bpp = panel.panel_info.bpp;panel.fb.format = panel.panel_info.mipi.dst_format;} else if (pan_type == PANEL_TYPE_EDP) {mdss_edp_panel_init(&(panel.panel_info));/* prepare func is set up at edp_panel_init */panel.clk_func = mdss_edp_panel_clock;panel.power_func = mdss_edp_panel_power;panel.bl_func = mdss_edp_bl_enable;panel.fb.format = FB_FORMAT_RGB888;} else {dprintf(CRITICAL, "Target panel init not found!\n");ret = ERR_NOT_SUPPORTED;goto error_gcdb_display_init;}panel.fb.base = base;panel.mdp_rev = rev;ret = msm_display_init(&panel);error_gcdb_display_init:display_enable = ret ? 0 : 1;return ret;
}
再调用下面函数： // 配置lcd.
int msm_display_init(struct msm_fb_panel_data *pdata)
{int ret = NO_ERROR;panel = pdata;if (!panel) {ret = ERR_INVALID_ARGS;goto msm_display_init_out;}/* Turn on panel */if (pdata->power_func)ret = pdata->power_func(1, &(panel->panel_info));if (ret)goto msm_display_init_out;if (pdata->dfps_func)ret = pdata->dfps_func(&(panel->panel_info));/* Enable clock */if (pdata->clk_func)ret = pdata->clk_func(1, &(panel->panel_info));if (ret)goto msm_display_init_out;/* Read specifications from panel if available.* If further clocks should be enabled, they can be enabled* using pll_clk_func*/if (pdata->update_panel_info)ret = pdata->update_panel_info();if (ret)goto msm_display_init_out;/* Enabled for auto PLL calculation or to enable* additional clocks*/if (pdata->pll_clk_func)ret = pdata->pll_clk_func(1, &(panel->panel_info));if (ret)goto msm_display_init_out;/* pinfo prepare */if (pdata->panel_info.prepare) {/* this is for edp which pinfo derived from edid */ret = pdata->panel_info.prepare();panel->fb.width = panel->panel_info.xres;panel->fb.height = panel->panel_info.yres;panel->fb.stride = panel->panel_info.xres;panel->fb.bpp = panel->panel_info.bpp;}if (ret)goto msm_display_init_out;ret = msm_fb_alloc(&(panel->fb));if (ret)goto msm_display_init_out;fbcon_setup(&(panel->fb));display_image_on_screen();if ((panel->dsi2HDMI_config) && (panel->panel_info.has_bridge_chip))ret = panel->dsi2HDMI_config(&(panel->panel_info));if (ret)goto msm_display_init_out;ret = msm_display_config();if (ret)goto msm_display_init_out;ret = msm_display_on();if (ret)goto msm_display_init_out;if (pdata->post_power_func)ret = pdata->post_power_func(1);if (ret)goto msm_display_init_out;/* Turn on backlight */if (pdata->bl_func)ret = pdata->bl_func(1);if (ret)goto msm_display_init_out;msm_display_init_out:return ret;
}
再调用，下面函数；
void display_image_on_screen(void)
{
#if DISPLAY_TYPE_MIPIint fetch_image_from_partition();dprintf(INFO, "display_image_on_screen-1\n");if (fetch_image_from_partition() < 0) {display_default_image_on_screen();} else {/* data has been put into the right place */fbcon_flush();}
#elsedisplay_default_image_on_screen();
#endif
}
再调用显示logo函数:
void display_default_image_on_screen(void)
{unsigned i = 0;unsigned total_x;unsigned total_y;unsigned bytes_per_bpp;unsigned image_base;
#if DISPLAY_TYPE_MIPIchar *image = NULL;
#endifif (!config) {dprintf(CRITICAL,"NULL configuration, image cannot be displayed\n");return;}fbcon_clear(); // clear screen with Black colortotal_x = config->width;total_y = config->height;bytes_per_bpp = ((config->bpp) / 8);image_base = ((((total_y/2) - (SPLASH_IMAGE_HEIGHT / 2) - 1) *(config->width)) + (total_x/2 - (SPLASH_IMAGE_WIDTH / 2)));#if DISPLAY_TYPE_MIPI
#if ENABLE_WBCimage = (pm_appsbl_charging_in_progress() ? image_batt888 : imageBuffer_rgb888);
#elseimage = imageBuffer_rgb888;
#endifif (bytes_per_bpp == 3) {for (i = 0; i < SPLASH_IMAGE_HEIGHT; i++) {memcpy (config->base + ((image_base + (i * (config->width))) * bytes_per_bpp),image + (i * SPLASH_IMAGE_WIDTH * bytes_per_bpp),SPLASH_IMAGE_WIDTH * bytes_per_bpp);}}fbcon_flush();
#if DISPLAY_MIPI_PANEL_NOVATEK_BLUEif(is_cmd_mode_enabled())mipi_dsi_cmd_mode_trigger();
#endif#elseif (bytes_per_bpp == 2) {for (i = 0; i < SPLASH_IMAGE_HEIGHT; i++) {memcpy (config->base + ((image_base + (i * (config->width))) * bytes_per_bpp),imageBuffer + (i * SPLASH_IMAGE_WIDTH * bytes_per_bpp),SPLASH_IMAGE_WIDTH * bytes_per_bpp);}}fbcon_flush();
#endif
}
在以上函数中，fbcon_clear() 是清屏。
fbcon_clear(); // clear screen with Black color
config->width; // screen total width config->height // screen total high image_base // 显示的screen的中心基准。改变这个image_base 的中心基准值，可以改变图片的显示位置。
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