高通移植mipi LCD的过程LK代码

时间:2021-04-05 08:13:10

lk部分:(实现LCD兼容)

1. 函数定位

aboot_init()来到target_display_init()

这就是高通原生lk LCD 兼容的关键所在。至于你需要兼容多少LCD 就在while()设置了,具体代码就不跟下去了。

然后根据target中的不同文件来判断是否进入哪一个函数来处理:

target_display_init() 函数里有很重要函数就是gcdb_display_init();

如果平台支持屏幕最大个数自动检测,msm8953支持兼容两个屏。(GCDB:Global Component Database全局组件数据库);

gcdb_display_init初始化pll_clk_func、power_func、bl_func等功能(指明相应的函数指针),初始化好之后就调用msm_display_init()函数。

在msm_display_init()里先Turn on panel,再Turn on backlight;

panel.power_func = mdss_dsi_panel_power;		//turn on panel
panel.bl_func = mdss_dsi_bl_enable; //turn on backlight

函数指向相应的函数中去;

2. 打开lcd

/* Turn on panel */

1. 调用mdss_dsi_panel_power()中的regulator_enable()给L2、L6、L17供电

if (pdata->power_func)
ret = pdata->power_func(1, &(panel->panel_info));

2. 调用mdss_dsi_mipi_dfps_config函数:

if (pdata->dfps_func)
ret = pdata->dfps_func(&(panel->panel_info));

3. 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。

4. 分配并设置帧缓存:

msm_fb_alloc(&(panel->fb))fbcon_setup(&(panel->fb))为帧缓冲器(frame buffer)分配内存。

5. 获取logo图片:

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。

6. DSI转HDMI:

if ((panel->dsi2HDMI_config) && (panel->panel_info.has_bridge_chip))
ret = panel->dsi2HDMI_config(&(panel->panel_info));

7. msm_display_config()函数:

7.1 mdss_dsi_phy_init()

mdss_dsi_phy_init(&mipi_pinfo,MIPI_DSI0_BASE, DSI0_PHY_BASE);
if(pinfo->mipi.dual_dsi)

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。

mdss_dsi_phy_init(&mipi_pinfo,MIPI_DSI1_BASE, DSI1_PHY_BASE);

7.2 ret = mdss_dsi_host_init(mipi, mipi->dual_dsi, mipi->broadcast);

初始化DSI接口的host控制器。

7.3 调用if (panel->pre_init_func) {}函数:

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_initinit_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。

8. ret = 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)
goto msm_display_on_out; ret = mdss_dsi_post_on(panel);
if (ret)
goto msm_display_on_out; ret = mipi_dsi_on(pinfo);
if (ret)
goto msm_display_on_out;
break;

8.1 调用mdp_dsi_video_on()使能DSI VIDEO

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

8.3 mipi_dsi_on()

9. 打开背光:

/* Turn on backlight */
if (pdata->bl_func)
ret = pdata->bl_func(1);

3. 增加一个panel需要做的事:

1、在gcdb_display_init()函数中有一个函数oem_panel_select()函数:

(这个函数需要做的工作是:主要是识别不同IC,赋值给参数panel_id,panel_id的使用在同一文件中的 init_panel_data()函数中。)

pan_type = oem_panel_select(panel_name, &panelstruct, &(panel.panel_info),
&dsi_video_mode_phy_db);

2、uint32_t hw_id = board_hardware_id();

//判断是高通哪一款平台,这里不需要看,hw_id是不需要管的,因为在下面语句中会直接跳到init_panel_data函数中来

3、在oem_panel_select()函数中需要根据你的hw_id来确定使用哪一款的LCD;

panel_override_id = panel_name_to_id(supp_panels,
ARRAY_SIZE(supp_panels), panel_name);
supp_panels是struct panel_list,如果要增加一个panel就需要在这里增加一个supp_panels,例如:
static struct panel_list supp_panels[] = {
{"truly_1080p_video", TRULY_1080P_VIDEO_PANEL},
{"truly_1080p_cmd", TRULY_1080P_CMD_PANEL},
{"r69006_1080p_video", R69006_1080P_VIDEO_PANEL},
{"r69006_1080p_cmd", R69006_1080P_CMD_PANEL},
{"truly_wuxga_video", TRULY_WUXGA_VIDEO_PANEL},
{"nt35523_720p_video", NT35523_720P_VIDEO_PANEL},
{"a914_nhd_video", A914_NHD_VIDEO_PANEL},
};

4、在这个枚举中也需要增加相应的panel:

/*---------------------------------------------------------------------------*/
enum {
TRULY_1080P_VIDEO_PANEL,
TRULY_1080P_CMD_PANEL,
R69006_1080P_VIDEO_PANEL,
R69006_1080P_CMD_PANEL,
TRULY_WUXGA_VIDEO_PANEL,
NT35523_720P_VIDEO_PANEL,
A914_NHD_VIDEO_PANEL,
UNKNOWN_PANEL
}; if (panel_name) {
panel_override_id = panel_name_to_id(supp_panels,
ARRAY_SIZE(supp_panels), panel_name); if (panel_override_id < 0) {
dprintf(CRITICAL, "Not able to search the panel:%s\n",
panel_name + strspn(panel_name, " "));
} else if (panel_override_id < UNKNOWN_PANEL) {
/* panel override using fastboot oem command */
panel_id = panel_override_id; dprintf(INFO, "OEM panel override:%s\n",
panel_name + strspn(panel_name, " "));
goto panel_init;
}
}
……
panel_init:
/*
* Update all data structures after 'panel_init' label. Only panel
* selection is supposed to happen before that.
*/
pinfo->pipe_type = MDSS_MDP_PIPE_TYPE_RGB;
return init_panel_data(panelstruct, pinfo, phy_db);

确保能直接跳到panel_init函数中来;

5、同样来到init_panel_data()函数中来:

在这里也需要增加一个panel:(当然了,要增加相应的头文件#include "include/panel_a914_nhd_video.h"这个头文件是LCM供应商给的文件,一般来说都要自己根据时序图来参照)

case TRULY_WUXGA_VIDEO_PANEL:
panelstruct->paneldata = &truly_wuxga_video_panel_data;
panelstruct->paneldata->panel_with_enable_gpio = 1;
panelstruct->panelres = &truly_wuxga_video_panel_res;
panelstruct->color = &truly_wuxga_video_color;
panelstruct->videopanel = &truly_wuxga_video_video_panel;
panelstruct->commandpanel = &truly_wuxga_video_command_panel;
panelstruct->state = &truly_wuxga_video_state;
panelstruct->laneconfig = &truly_wuxga_video_lane_config;
panelstruct->paneltiminginfo
= &truly_wuxga_video_timing_info;
panelstruct->panelresetseq
= &truly_wuxga_video_panel_reset_seq;
panelstruct->backlightinfo = &truly_wuxga_video_backlight;
pinfo->mipi.panel_on_cmds
= truly_wuxga_video_on_command;
pinfo->mipi.num_of_panel_on_cmds
= TRULY_WUXGA_VIDEO_ON_COMMAND;
pinfo->mipi.panel_off_cmds
= truly_wuxga_video_off_command;
pinfo->mipi.num_of_panel_off_cmds
= TRULY_WUXGA_VIDEO_OFF_COMMAND;
memcpy(phy_db->timing,
truly_wuxga_14nm_video_timings, MAX_TIMING_CONFIG * sizeof(uint32_t));
pinfo->dfps.panel_dfps = truly_wuxga_video_dfps;
pinfo->mipi.signature = TRULY_WUXGA_VIDEO_SIGNATURE;
break;
case A914_NHD_VIDEO_PANEL:
panelstruct->paneldata = &a914_nhd_video_panel_data;
panelstruct->panelres = &a914_nhd_video_panel_res;
panelstruct->color = &a914_nhd_video_color;
panelstruct->videopanel = &a914_nhd_video_video_panel;
panelstruct->commandpanel = &a914_nhd_video_command_panel;
panelstruct->state = &a914_nhd_video_state;
panelstruct->laneconfig = &a914_nhd_video_lane_config;
panelstruct->paneltiminginfo
= &a914_nhd_video_timing_info;
panelstruct->panelresetseq
= &a914_nhd_video_panel_reset_seq;
panelstruct->backlightinfo = &a914_nhd_video_backlight;
pinfo->mipi.panel_on_cmds
= a914_nhd_video_on_command;
pinfo->mipi.num_of_panel_on_cmds
= A914_NHD_VIDEO_ON_COMMAND;
pinfo->mipi.panel_off_cmds
= a914_nhd_video_off_command;
pinfo->mipi.num_of_panel_off_cmds
= A914_NHD_VIDEO_OFF_COMMAND;
memcpy(phy_db->timing,
a914_nhd_video_timings, MAX_TIMING_CONFIG * sizeof(uint32_t));
pinfo->mipi.signature = A914_NHD_VIDEO_SIGNATURE;
break;

6、调整背光:

gcdb_display_init()函数中有一个函数指针mdss_dsi_bl_enable

这个函数是用来调整背光的和使能背光的,通过PWM来作用:(具体要看原理图)

static int mdss_dsi_bl_enable(uint8_t enable)
{
int ret = NO_ERROR; ret = panel_backlight_ctrl(enable);
if (ret)
dprintf(CRITICAL, "Backlight %s failed\n", enable ? "enable" :
"disable");
return ret;
} static uint32_t panel_backlight_ctrl(uint8_t enable)
{
uint32_t ret = NO_ERROR;
if (panelstruct.backlightinfo)
ret = target_backlight_ctrl(panelstruct.backlightinfo, enable);
return ret;
}

所以bootloader的背光是通过target_backlight_ctrl()控制的,找到该项目的这个函数修改:

wled_backlight_ctrl

7、更改LCD的参数:

LCD的一些参数:

VBPD(verticalback porch):表示在一帧图像开始时,垂直同步信号以后的无效的行数。

VFPD(verticalfront porch):表示在一帧图像结束后,垂直同步信号以前的无效的行数。

VSPW(verticalsync pulse width):表示垂直同步脉冲的宽度,用行数计算。

HBPD(horizontal back porch):表示从水平同步信号开始到一行的有效数据开始之间的VCL的个数。

HFPD(horizontal front porch):表示一行的有效数据结束到下一个水平同步信号开始 之间的VCLK的个数。

HSPW(horizontalsync pulse width):表示水平同步信号的宽度,用VCLK计算。