MSM8909+Android5.1.1启动流程---LCM初始化

\bootable\bootloader\lk\app\aboot\aboot.c

aboot_init()--->target_display_init()--->gcdb_display_init()

gcdb_display_init()函数的调用流程

图1

Mipi接口的显示屏初始化设置流程：

图2

下面介绍这些函数

1.     oem_panel_selec()

根据传递进来的panel_name和supp_panels[]匹配到panel id

/*

*The list of panels that are supported on this target.

*Any panel in this list can be selected using fastboot oem command.

*/

static struct panel_list supp_panels[] = {

{"hx8394d_720p_video",HX8394D_720P_VIDEO_PANEL},

{"sharp_qhd_video",SHARP_QHD_VIDEO_PANEL},

{"truly_wvga_cmd",TRULY_WVGA_CMD_PANEL},

{"hx8379a_fwvga_skua_video",HX8379A_FWVGA_SKUA_VIDEO_PANEL},

{"ili9806e_wvga_video",ILI9806E_WVGA_VIDEO_PANEL},

…

{"jd9161ba_fwvga_video_panel",JD9161BA_FWVGA_VIDEO_PANEL},

};

先调用board_hardware_id()和board_hardware_subtype()获取board.platform_hw与board.platform_subtype，我们分别是11(HW_PLATFORM_QRD)和12(QRD_SKUE_projectname)

msm8909-1gb-qrd-skue.dts文件相关内容

qcom,board-id= <0x1000b 0x8>;

b对应于

uint32_t board_hardware_id()

{

returnboard.platform_hw;

}

8对应于

uint32_t board_hardware_subtype(void)

{

returnboard.platform_subtype;

}

然后调用init_panel_data()初始化panel数据，主要初始化panel_struct结构体数据，然后返回panel类型PANEL_TYPE_DSI。

typedef struct panel_struct{

int (*read_id)(void); //add by zougang

structpanel_config *paneldata;

structpanel_resolution *panelres;

structcolor_info *color;

structvideopanel_info *videopanel;

structcommandpanel_info *commandpanel;

structcommand_state *state;

structlane_configuration *laneconfig;

structpanel_timing *paneltiminginfo;

structpanel_reset_sequence *panelresetseq;

structbacklight *backlightinfo;

structfb_compression fbcinfo;

};

此结构体对应/dsi-panel-ili9806e-wvga-video.dtsi文件，此结构体主要成员如下

(1)  panel_config

/*Panel Configuration */

typedef struct panel_config{

char *panel_node_id;// qcom,mdss_dsi_ili9806e_wvga_video

char *panel_controller;// "dsi:0:"

char *panel_compatible;// "qcom,mdss-dsi-panel"

uint16_tpanel_interface;//10

uint16_tpanel_type;//0

char *panel_destination;// "DISPLAY_1"

uint32_tpanel_orientation;//0

uint32_tpanel_clockrate;//0

uint16_tpanel_framerate;//60

uint16_tpanel_channelid;//0

uint16_tdsi_virtualchannel_id;//0

uint16_tpanel_broadcast_mode;//0

uint16_tpanel_lp11_init;//0

uint16_tpanel_init_delay;//0

uint16_tdsi_stream;//0

uint8_t interleave_mode;//0

uint32_tpanel_bitclock_freq;

uint32_tpanel_operating_mode;//0

uint32_tpanel_with_enable_gpio;//0

uint8_t mode_gpio_state;//0

char *slave_panel_node_id;//0

};

(2)  panel_resolution

typedef struct panel_resolution{

uint16_tpanel_width;

uint16_tpanel_height;

uint16_thfront_porch;

uint16_thback_porch;

uint16_thpulse_width;

uint16_thsync_skew;

uint16_tvfront_porch;

uint16_tvback_porch;

uint16_tvpulse_width;

uint16_thleft_border;

uint16_thright_border;

uint16_tvtop_border;

uint16_tvbottom_border;

uint16_thactive_res;

uint16_tvactive_res;

uint16_tinvert_data_polarity;

uint16_tinvert_vsync_polarity;

uint16_tinvert_hsync_polarity;

};

Panel的分辨率、时序参数、极性等数据。

(3)  color_info

typedef struct color_info{

uint8_t color_format;//24位色

uint8_t color_order;

uint8_t underflow_color;

uint8_t border_color;

uint8_t pixel_packing;

uint8_t pixel_alignment;

};

Panel color信息。

(4)   lane_configuration

typedef struct lane_configuration {

uint8_tdsi_lanes;//比如2个lane，但大分辨率如720*1280，需要4lane

uint8_tdsi_lanemap;

uint8_tlane0_state;

uint8_tlane1_state;

uint8_tlane2_state;

uint8_tlane3_state;

};

这里可看出只支持到4lane，支持的lane对应的state为1，否则为0。

(5)  panel_timing

typedef struct panel_timing {

uint8_tdsi_mdp_trigger;// "none"

uint8_tdsi_dma_trigger;// "trigger_sw"

uint8_ttclk_post;

uint8_ttclk_pre;

};

(6)  panel_reset_sequence

typedef struct panel_reset_sequence {

uint8_tpin_state[TOTAL_RESET_GPIO_CTRL];

uint32_tsleep[TOTAL_RESET_GPIO_CTRL];

uint8_tpin_direction;

};

对应设备树文件的qcom,mdss-dsi-reset-sequence =<1 20>, <0 20>, <1 20>;

这里可让pin状态及演示多久后再修改pin状态。

(7)  backlight

typedef struct backlight {

uint16_tbl_interface_type;//1，对应"bl_ctrl_pwm"

uint16_tbl_min_level;//背光最小值

uint16_tbl_max_level;//背光最大值

uint16_tbl_step;//间隔值

uint16_tbl_pmic_controltype;//1，表示"bl_ctrl_pwm"

char *bl_pmic_model;// "PMIC_8941"

};

2.     init_platform_data()

static void init_platform_data()

{

memcpy(dsi_video_mode_phy_db.regulator,panel_regulator_settings,

REGULATOR_SIZE);

memcpy(dsi_video_mode_phy_db.ctrl,panel_physical_ctrl,

PHYSICAL_SIZE);

memcpy(dsi_video_mode_phy_db.strength,panel_strength_ctrl,

STRENGTH_SIZE);

memcpy(dsi_video_mode_phy_db.bistCtrl,panel_bist_ctrl, BIST_SIZE);

memcpy(dsi_video_mode_phy_db.laneCfg,panel_lane_config, LANE_SIZE);

}

初始化mdss_dsi_phy_ctrl结构体成员

struct mdss_dsi_phy_ctrl {

uint32_tregulator[MAX_REGULATOR_CONFIG];

uint32_ttiming[MAX_TIMING_CONFIG];

uint32_tctrl[MAX_CTRL_CONFIG];

uint32_tstrength[MAX_STRENGTH_CONFIG];

charbistCtrl[MAX_BIST_CONFIG];

charlaneCfg[MAX_LANE_CONFIG];

enumdsi_reg_mode regulator_mode;

intis_pll_20nm;

};

3.     dsi_panel_init()

用在init_panel_data()初始化的全局变量panelstruct来初始化panel.panel_info，其中包含对msm_panel_info结构体中函数指针的赋值，如下：

pinfo->pre_on = dsi_panel_pre_on;

pinfo->pre_off= dsi_panel_pre_off;

pinfo->on= dsi_panel_post_on;

pinfo->off= dsi_panel_post_off;

pinfo->rotate= dsi_panel_rotation;

pinfo->config= dsi_panel_config;

4.     初始化panel全局变量的其他结构体成员

panel.panel_info.mipi.mdss_dsi_phy_db =&dsi_video_mode_phy_db;

panel.pll_clk_func= mdss_dsi_panel_clock;

panel.power_func= mdss_dsi_panel_power;

panel.pre_init_func= mdss_dsi_panel_pre_init;

panel.bl_func= mdss_dsi_bl_enable;

panel.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;

5.     msm_display_init(&panel)

5.1  调用mdss_dsi_panel_power()给DSI panel供电

(1)  target_ldo_ctrl()--->regulator_enable()给L2、L6和L17供电

(2)  是否调用mdss_dsi_panel_reset()

/* Panel Reset */

if(!panelstruct.paneldata->panel_lp11_init) {

ret= mdss_dsi_panel_reset(enable);

if(ret) {

dprintf(CRITICAL,"panel reset failed\n");

returnret;

}

}

由于我们这里的panelstruct.paneldata->panel_lp11_init在init_panel_data()函数赋值为1，所以这里暂时不调用mdss_dsi_panel_reset(enable)。

5.2  调用mdss_dsi_panel_clock()

调用calculate_clock_config(pinfo)计算时钟配置和调用target_panel_clock(enable, pinfo)配置目标panel的时钟。

5.3  msm_fb_alloc(&(panel->fb))和fbcon_setup(&(panel->fb))

为帧缓冲器(frame buffer)分配内存。

5.4  display_image_on_screen()

调用fetch_image_from_partition()从splash分区获取lk logo图片，如果splash分区没有满足要求的数据，就显示默认的logo。

5.5  msm_display_config()

根据pinfo->type，比如我们这里是MIPI_VIDEO_PANEL来配置msm平台display，配置时还需要根据MDP(MobileDisplay processor)的版本来调用对应的config函数，如下：

mdp_rev = mdp_get_revision();

if(mdp_rev == MDP_REV_50 || mdp_rev == MDP_REV_304 ||

mdp_rev== MDP_REV_305)

ret= mdss_dsi_config(panel);

else

ret= mipi_config(panel);

msm8909是MDP_REV_305版本(MDP 3.05)，所以调用mdss_dsi_config(panel)

5.5.1       mdss_dsi_config(panel)

(1)  mdss_dsi_phy_init()

mdss_dsi_phy_init(&mipi_pinfo,MIPI_DSI0_BASE, DSI0_PHY_BASE);

if(pinfo->mipi.dual_dsi)

mdss_dsi_phy_init(&mipi_pinfo,MIPI_DSI1_BASE, DSI1_PHY_BASE);

如果有两个MIPI DSI接口MIPI_DSI0和MIPI_DSI1就调用两次mdss_dsi_phy_init()，msm8909只有MIPI_DSI0，MSM8994等有两个DSI接口。

(2)  mdss_dsi_host_init()

初始化DSI接口的host控制器。

(3)  mdss_dsi_panel_pre_init()

static int mdss_dsi_panel_pre_init(void)

{

intret = NO_ERROR;

if(panelstruct.paneldata->panel_lp11_init) {

ret= mdss_dsi_panel_reset(1);

if(ret) {

dprintf(CRITICAL,"panel reset failed\n");

returnret;

}

}

if(panelstruct.paneldata->panel_init_delay)

udelay(panelstruct.paneldata->panel_init_delay);

dprintf(SPEW,"Panel pre init done\n");

returnret;

}因为panelstruct.paneldata->panel_lp11_init在init_panel_data()函数赋值为1，所以调用mdss_dsi_panel_reset()根据reset时序来复位panel。

(4)  read_id()读显示屏id

此函数指针read_id在init_panel_data()中赋值，这是自己增加的一部分，主要是为了兼容不同显示屏。

(5)  旋转显示屏

if (pinfo->rotate &&panel->rotate)

pinfo->rotate();

dsi_panel_init()中用pinfo->rotate = dsi_panel_rotation初始化，dsi_panel_rotation()直接调用oem_panel_rotation()返回NO_ERROR，没有实际旋转的动作。

5.5.2       mdp_dsi_video_config(pinfo,&(panel->fb))

配置DSI VIDEO模式

5.6  msm_display_on()

主要部分：

case MIPI_VIDEO_PANEL:

dprintf(INFO,"Turn on MIPI_VIDEO_PANEL.\n");

ret= mdp_dsi_video_on(pinfo);

if(ret)

gotomsm_display_on_out;

ret= mdss_dsi_post_on(panel);

if(ret)

gotomsm_display_on_out;

ret= mipi_dsi_on();

if(ret)

gotomsm_display_on_out;

break;

(1)  调用mdp_dsi_video_on()使能DSI VIDEO

(2)  mdss_dsi_post_on()使用初始化命令来初始化panel

mipi_pinfo.panel_cmds = pinfo->mipi.panel_cmds;

mipi_pinfo.num_of_panel_cmds= pinfo->mipi.num_of_panel_cmds;

mipi_pinfo.signature= pinfo->mipi.signature;

ret= mdss_dsi_panel_initialize(&mipi_pinfo, pinfo->mipi.broadcast);

对应qcom,mdss-dsi-on-command部分。

(3)  mipi_dsi_on()

5.7  打开背光

/* Turn on backlight */

if(pdata->bl_func)

ret= pdata->bl_func(1);

对应调用mdss_dsi_bl_enable()--->panel_backlight_ctrl(enable)--->

target_backlight_ctrl(panelstruct.backlightinfo,enable)

可知根据panelstruct.backlightinfo来进行背光控制，而panelstruct.backlightinfo在oem_panel_select()--->init_panel_data()被赋值

panelstruct->backlightinfo =&ili9806e_fwvga_video_backlight;

参考：

高通平台MSM8916LCM模块移植(一)-bootloader部分

http://blog.csdn.net/penghcai/article/details/43227005