轉載請注明出處：https://www.cnblogs.com/lialong1st/p/9174475.html
CPU：RK3288
系統：Android 5.1
本帖以 HDMI 800x600p-60 為例，添加新的分辨率。
1、修改文件，打開調試模式，得到 EDID 信息后，記得關閉
diff --git a/kernel/drivers/video/fbmon.c b/kernel/drivers/video/fbmon.c index 6103fa6..ce9b11e 100755 --- a/kernel/drivers/video/fbmon.c +++ b/kernel/drivers/video/fbmon.c @@ -43,7 +43,8 @@ * EDID parser */ -#undef DEBUG /* define this for verbose EDID parsing output */ +//#undef DEBUG /* define this for verbose EDID parsing output */ +#define DEBUG #ifdef DEBUG #define DPRINTK(fmt, args...) printk(fmt,## args)
2、打印出 EDID 信息
[ 0.805638] ======================================== [ 0.805652] Display Information (EDID) [ 0.805662] ======================================== [ 0.805672] EDID Version 1.3 [ 0.805682] Manufacturer: ROW [ 0.805691] Model: 0 [ 0.805699] Serial#: 0 [ 0.805708] Year: 2014 Week 12 [ 0.805719] Monitor Name: AAA [ 0.805728] Display Characteristics: [ 0.805738] Monitor Operating Limits: From EDID [ 0.805754] H: 30-80KHz V: 50-76Hz DCLK: 160MHz [ 0.805764] Digital Display Input Sync: [ 0.805780] Max H-size in cm: variable [ 0.805791] Max V-size in cm: variable [ 0.805801] Gamma: 1.0 [ 0.805813] DPMS: Active yes, Suspend no, Standby yes [ 0.805823] Unknown [ 0.805832] Chroma [ 0.805840] RedX: 0.636 RedY: 0.349 [ 0.805852] GreenX: 0.290 GreenY: 0.589 [ 0.805863] BlueX: 0.143 BlueY: 0.080 [ 0.805875] WhiteX: 0.313 WhiteY: 0.329 [ 0.805886] First DETAILED Timing is preferred [ 0.805899] Detailed Timings [ 0.805910] 40 MHz 800 840 968 1056 600 601 605 628 +HSync +VSync [ 0.805932] Supported VESA Modes [ 0.805945] 720x400@70Hz [ 0.805955] 640x480@60Hz [ 0.805964] 640x480@72Hz [ 0.805972] 640x480@75Hz [ 0.805980] 800x600@56Hz [ 0.805988] 800x600@60Hz [ 0.805997] 800x600@72Hz [ 0.806005] 800x600@75Hz [ 0.806014] Manufacturer's mask: 0 [ 0.806023] Standard Timings [ 0.806034] ========================================
Detailed Timings 是主要的 LCD 參數，Supported VESA Modes 是 LCD 支持的分辨率。
通過源碼查看各參數的含義：
路徑：kernel/drivers/video/fbmon.c
DPRINTK(" %d MHz ", PIXEL_CLOCK/1000000); DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET, H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING); DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET, V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING); DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-", (VSYNC_POSITIVE) ? "+" : "-");
由此可以得到 LCD 的各參數：
40M = PIXEL_CLOCK = pixclock 800 = H_ACTIVE = xres 840 = H_ACTIVE + H_SYNC_OFFSET = xres + h_fp = 800 + 40 968 = H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH = xres + h_fp + h_pw = 800 + 40 + 128 1056 = H_ACTIVE + H_BLANKING = xres + h_bp + h_fp + h_pw = 800 + 88 + 40 + 128 600 = V_ACTIVE = yres 601 = V_ACTIVE + V_SYNC_OFFSET = yres + v_fp = 600 + 1 605 = V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH = yres + v_fp + v_pw = 600 + 1 + 4 628 = V_ACTIVE + V_BLANKING = yres + v_bp + v_fp + v_pw = 600 + 23 + 1 + 4 +HSync = HSYNC_POSITIVE +VSync = VSYNC_POSITIVE
3、在枚舉中增加此分辨率，枚舉值為 108，並修改默認分辨率
diff --git a/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi.h b/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi.h index b5475e4..f31f5b9 100755 --- a/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi.h +++ b/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi.h @@ -129,6 +129,7 @@ enum hdmi_video_infomation_code { HDMI_3840X2160P_30HZ_4_3, /*105*/ HDMI_3840X2160P_50HZ_4_3, HDMI_3840X2160P_60HZ_4_3, + HDMI_800X600P_60HZ, /*108*/ }; /* HDMI Extended Resolution */ @@ -474,7 +475,7 @@ struct hdmi { #define HDMI_AUTO_CONFIG false /* HDMI default vide mode */ -#define HDMI_VIDEO_DEFAULT_MODE HDMI_1920X1080P_60HZ//HDMI_1280X720P_60HZ +#define HDMI_VIDEO_DEFAULT_MODE HDMI_800X600P_60HZ//HDMI_1920X1080P_60HZ//HDMI_1280X720P_60HZ /*HDMI_1920X1080P_60HZ*/ #define HDMI_VIDEO_DEFAULT_COLORMODE HDMI_COLOR_AUTO #define HDMI_VIDEO_DEFAULT_COLORDEPTH 8
4、將屏參數據添加到數組 static const struct hdmi_video_timing hdmi_mode[] 中
/* name refresh xres yres pixclock h_bp h_fp v_bp v_fp h_pw v_pw polariry PorI flag vic 2ndvic pixelrepeat interface */
/* 名稱 刷新頻率 行像素 列像素 像素時鍾 水平后沿 水平前沿 垂直后沿 垂直前沿 行同步脈寬 列同步脈寬 極性 掃描方式 標志 枚舉值 第二枚舉值 像素重復 接口*/
diff --git a/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi-lcdc.c b/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi-lcdc.c index 63a5cfb..0f920c2 100755 --- a/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi-lcdc.c +++ b/kernel/drivers/video/rockchip/hdmi/rockchip-hdmi-lcdc.c @@ -7,6 +7,7 @@ static const struct hdmi_video_timing hdmi_mode[] = { { { "720x576i@50Hz", 50, 720, 576, 27000000, 69, 12, 19, 2, 63, 3, 0, 1, 0 }, 21, HDMI_720X576I_50HZ_16_9, 2, OUT_P888}, { { "720x480p@60Hz", 60, 720, 480, 27000000, 60, 16, 30, 9, 62, 6, 0, 0, 0 }, 2, HDMI_720X480P_60HZ_16_9, 1, OUT_P888}, { { "720x576p@50Hz", 50, 720, 576, 27000000, 68, 12, 39, 5, 64, 5, 0, 0, 0 }, 17, HDMI_720X576P_50HZ_16_9, 1, OUT_P888}, + { { "800x600p@60Hz", 60, 800, 600, 40000000, 88, 40, 23, 1, 128, 4, FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT, 0, 0}, 108, HDMI_800X600P_60HZ, 1, OUT_P888}, { { "1280x720p@24Hz", 24, 1280, 720, 59400000, 220, 1760, 20, 5, 40, 5, FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT, 0, 0}, 60, HDMI_1280X720P_24HZ_4_3, 1, OUT_P888}, { { "1280x720p@25Hz", 25, 1280, 720, 74250000, 220, 2420, 20, 5, 40, 5, FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT, 0, 0}, 61, HDMI_1280X720P_25HZ_4_3, 1, OUT_P888}, { { "1280x720p@30Hz", 30, 1280, 720, 74250000, 220, 1760, 20, 5, 40, 5, FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT, 0, 0}, 62, HDMI_1280X720P_30HZ_4_3, 1, OUT_P888},
polariry：水平同步高電平有效和垂直同步高電平有效
PorI：0 為不是隔行掃描。定義文件路徑：/kernel/include/uapi/linux/fb.h
flag：不知道什么意思
vic：在分辨率枚舉中的編號，本次添加的為 108
5、此時 HDMI 可以正常輸入 800x600 的分辨率，但是實際顯示可能有問題。
根據顯示器的 EDID 修改 dts 中加載的屏參文件，修改值與添加到 HDMI 數組中的相同。
diff --git a/kernel/arch/arm/boot/dts/lcd-800x600.dtsi b/kernel/arch/arm/boot/dts/lcd-800x600.dtsi index c0baf15..733a157 100755 --- a/kernel/arch/arm/boot/dts/lcd-800x600.dtsi +++ b/kernel/arch/arm/boot/dts/lcd-800x600.dtsi @@ -15,12 +15,12 @@ clock-frequency = <40000000>; - hactive = <1920>; - vactive = <1080>; - hback-porch = <126>; - hfront-porch = <120>; - vback-porch = <10>; - vfront-porch = <10>; - hsync-len = <10>; - vsync-len = <8>; + hactive = <800>; + vactive = <600>; + hback-porch = <88>; + hfront-porch = <40>; + vback-porch = <23>; + vfront-porch = <1>; + hsync-len = <128>; + vsync-len = <4>; hsync-active = <0>; vsync-active = <0>; de-active = <0>;
6、編譯燒錄，HDMI 顯示正常，確認當前分辨率可以在設置 -> HDMI ->分辨率設置中查看，也可以通過指令查看。
$ cat /sys/class/display/HDMI/mode