3-DRM code-debug
阅读Linux DRM Developer's Guide，进行code 分析。。。。。。。。。。。。。。后面添加
Debug 手段。。。。。。。。。。。。。需要补充
sdm845:/sys/kernel/debug/drm_dp # cat dp_debug
state=0x0
link_rate=540000
num_lanes=2
resolution=0x0@0Hz
pclock=0KHz
bpp=0
test_req=unknown
lane_count=2
bw_code=20
v_level=0
p_level=0
sdm845:/sys/kernel/debug/drm_dp # cat dp_debug
state=0xa4
link_rate=540000
num_lanes=2
resolution=3840x1080@60Hz
pclock=297000KHz
bpp=24
test_req=unknown
lane_count=2
bw_code=20
v_level=0
p_level=0
sdm845:/sys/kernel/debug/drm_dp # cat edid_modes
3840x1080 60 0 4400 1125 297000 0x100005
3840x1080 60 2 4400 1125 296703 0x100005
1920x1080 60 0 2200 1125 148500 0x100005
1920x1080 60 2 2200 1125 148352 0x100005
1920x1080 50 2 2640 1125 148500 0x100005
1280x720 60 2 1650 750 74250 0x100005
1280x720 60 2 1650 750 74176 0x100005
1280x720 50 2 1980 750 74250 0x100005
720x480 60 1 858 525 27027 0x10000a
720x480 60 2 858 525 27000 0x10000a
640x480 60 1 800 525 25200 0x10000a
640x480 60 0 800 525 25175 0x10000a
drm 等级
/sys/module/drm/parameters/debug
查看dp clk
/sys/kernel/debug/clk/clk_summary
grep dp disp_cc_mdss_dp_pixel_clk_src
//获取眼镜的EDID，可以获取眼镜的链接状态
cat sys/class/drm/card0-DP-1/edid > /data/edid.bin
========================855Q ============================================
msmnile:/sys/kernel/debug/drm_dp # cat dp_debug
state=0xa5
link_rate=540000
num_lanes=2
resolution=3840x1080@60Hz
pclock=297000KHz
bpp=24
test_req=unknown
lane_count=2
bw_code=20
v_level=0
p_level=0
msmnile:/sys/kernel/debug/drm_dp # cat edid_modes
3840x1080 60 0 4400 1125 297000 0x800005
1920x1080 60 0 2200 1125 148500 0x800005
1920x1080 60 2 2200 1125 148352 0x800005
1920x1080 50 2 2640 1125 148500 0x800005
1280x720 60 2 1650 750 74250 0x800005
1280x720 60 2 1650 750 74176 0x800005
1280x720 50 2 1980 750 74250 0x800005
720x480 60 1 858 525 27027 0x80000a
720x480 60 2 858 525 27000 0x80000a
640x480 60 1 800 525 25200 0x80000a
640x480 60 0 800 525 25175 0x80000a
msmnile:/sys/class/drm/card0-DP-1 # cat modes
3840x1080
1920x1080
1920x1080
1920x1080
1280x720
1280x720
1280x720
720x480
720x480
640x480
640x480
msmnile:/sys/class/drm/card0-DP-1 # cat status
connected
