We are developing a stereo camera application on TX1/TX2 using R28.1.
When we moved to the TX2 we found problems regarding the PAL video output (720x576) over HDMI (TX1 working fine).
After a couple of minutes the video output turns red for some seconds (5-10).
The picture recovers mostly but the hsync is wrong (and stays stable) so that the bottom part of the pictures is getting displayed in the first lines.
So my question is what can lead to this underrun situation? I already checked the EMC speed but this seems to be fine.
TMDS config mode of 54MHz is getting used for this resolution:
tegradc 15200000.nvdisplay: hdmi: pclk:27000K, set prod-setting:prod_c_54Mt
cat /sys/kernel/debug/tegradc.0/stats
underflows: 1
underflows_a: 0
underflows_b: 0
underflows_c: 0
underflows_d: 0
underflows_h: 0
underflows_t: 0
underflow_frames: 1
./jetson_clocks.sh --show
SOC family:tegra186 Machine:afc-ecu
Online CPUs: 0-5
CPU Cluster Switching: Disabled
cpu0: Gonvernor=performance MinFreq=2035200 MaxFreq=2035200 CurrentFreq=2035200
cpu1: Gonvernor=performance MinFreq=2035200 MaxFreq=2035200 CurrentFreq=2035200
cpu2: Gonvernor=performance MinFreq=2035200 MaxFreq=2035200 CurrentFreq=2035200
cpu3: Gonvernor=performance MinFreq=2035200 MaxFreq=2035200 CurrentFreq=2035200
cpu4: Gonvernor=performance MinFreq=2035200 MaxFreq=2035200 CurrentFreq=2035200
cpu5: Gonvernor=performance MinFreq=2035200 MaxFreq=2035200 CurrentFreq=2035200
GPU MinFreq=1300500000 MaxFreq=1300500000 CurrentFreq=1300500000
EMC MinFreq=40800000 MaxFreq=1600000000 CurrentFreq=1600000000 FreqOverride=1
cat /sys/kernel/debug/clk/clk_summary
clock enable_cnt prepare_cnt rate req_rate accuracy phase
----------------------------------------------------------------------------------------------------------------------
vi 1 1 115200000 66500000 0 0
isp 1 1 115200000 70455264 0 0
sce_cpu_nic 1 1 473600000 473600000 0 0
se 0 0 601600000 601600000 0 0
eqos_rx_input 1 1 0 0 0 0
eqos_rx 1 1 0 0 0 0
axi_cbb 1 1 115200000 115200000 0 0
gpc2clk 1 1 0 0 0 0
gpcclk 1 1 114750000 114750000 0 0
sor1_pad_clkout 9 9 0 0 0 0
sor1_out 8 8 0 24000000 0 0
nvjpg 0 0 832000000 832000000 0 0
nvenc 0 0 1113600000 1113600000 0 0
vic 1 1 985600000 985600000 0 0
nvdec 0 0 1164800000 1164800000 0 0
tsecb 0 0 704000000 704000000 0 0
tsec 0 0 704000000 704000000 0 0
emc 0 0 1600000000 1600000000 0 0
osc 2 2 38400000 38400000 0 0
usb2_hsic_trk 1 1 9600000 9600000 0 0
hsic_trk 0 0 9600000 9600000 0 0
usb2_trk 1 1 9600000 9600000 0 0
spi2 1 1 38400000 38400000 0 0
nafll_disp 0 0 0 0 0 0
dflldisp_div 0 0 0 0 0 0
pwm4 0 0 38400000 38400000 0 0
clk_m 7 7 19200000 19200000 0 0
tach 1 1 1010526 1010526 0 0
spi4 1 1 19200000 19200000 0 0
fuse 1 1 19200000 19200000 0 0
kfuse 0 0 19200000 19200000 0 0
hda2hdmicodec 1 1 19200000 19200000 0 0
nvdisplay_p2 0 0 19200000 19200000 0 0
nvdisplay_p1 1 1 19200000 19200000 0 0
actmon 6 6 19200000 19200000 0 0
mipi_cal 1 1 19200000 19200000 0 0
dbgapb 0 0 19200000 19200000 0 0
clk_32k 0 0 32768 32768 0 0
aon_i2c_slow 0 0 32768 32768 0 0
i2c_slow 0 0 32768 32768 0 0
pll_ref 4 4 38400000 38400000 0 0
pll_nvcsi 1 1 450000000 450000000 0 0
nvcsi 2 2 112500000 92624992 0 0
pll_e 0 0 38400000 38400000 0 0
pll_c4_vco 0 0 784999218 784999218 0 0
pll_c4_out0 0 0 196249804 196249804 0 0
sdmmc4 0 0 196249804 196249804 0 0
pll_c4_vco_div2 0 0 392499609 392499609 0 0
pll_c4_out2 0 0 156999843 156999843 0 0
pll_c4_out1 0 0 261666406 261666406 0 0
pll_c4_out_mux 0 0 261666406 261666406 0 0
pllc4_out 0 0 261666406 261666406 0 0
pll_a_vco 0 0 258000000 258000000 0 0
pll_a 0 0 258000000 258000000 0 0
pll_a_out0 0 0 258000000 258000000 0 0
pll_disphub 0 0 307200000 307200000 0 0
plldisphub_div 0 0 307200000 307200000 0 0
pll_d3 0 0 25806426 25806426 0 0
pll_d2 2 2 148500000 148500000 0 0
sor1 1 1 148500000 148500000 0 0
nvdisplay_p0 4 4 148500000 148500000 0 0
nvdisplay_dsc 1 1 74250000 194000000 0 0
nvdisplay_disp 2 2 148500000 194000000 0 0
pll_d 0 0 582000000 582000000 0 0
pll_d_out1 0 0 582000000 582000000 0 0
pll_c2 0 0 307200000 307200000 0 0
pll_u 2 2 38400000 38400000 0 0
pll_u_480M 0 0 480000000 480000000 0 0
pll_u_48M 0 0 48000000 48000000 0 0
xusb_fs 0 0 48000000 48000000 0 0
xusb_dev 0 0 48000000 48000000 0 0
pll_refe_ref 1 1 60000000 60000000 0 0
pllrefe_iddq 1 1 60000000 60000000 0 0
pll_refe 1 1 625000000 625000000 0 0
pll_refe_out1 3 3 625000000 625000000 0 0
eqos_tx_clk 1 1 25000000 25000000 0 0
eqos_ptp_ref_clk 1 1 125000000 125000000 0 0
pllrefe_out1_div5 1 1 125000000 125000000 0 0
eqos_axi_clk 1 1 125000000 125000000 0 0
pll_refe_out 0 0 312500000 312500000 0 0
pllrefe_out_gated 0 0 312500000 312500000 0 0
pll_aon 0 0 480000000 480000000 0 0
pll_c 0 0 307200000 307200000 0 0
pll_p 4 4 408000000 408000000 0 0
pll_p_out5 1 1 204000000 204000000 0 0
gpu 1 1 204000000 204000000 0 0
pll_p_div17 1 1 24000000 24000000 0 0
sor_safe 12 12 24000000 24000000 0 0
dpaux1 0 0 24000000 24000000 0 0
host1x 5 5 102000000 102000000 0 0
pll_p_out0 19 19 408000000 408000000 0 0
sdmmc1 0 0 6000000 6000000 0 0
sdmmc3 0 0 204000000 204000000 0 0
spi1 1 1 4975610 5000000 0 0
nvcsilp 2 2 204000000 19200000 0 0
sce_apb 1 1 102000000 102000000 0 0
xusb 1 1 102000000 102000000 0 0
xusb_ss 0 0 102000000 102000000 0 0
uartd 0 0 408000000 19200000 0 0
uartc 0 0 408000000 38400000 0 0
uartb 0 0 408000000 19200000 0 0
uarta 1 1 408000000 408000000 0 0
hda2codec_2x 1 1 48000000 48000000 0 0
hda 1 1 51000000 51000000 0 0
extperiph2 2 2 24000000 24000000 0 0
extperiph1 2 2 24000000 24000000 0 0
nvdisplayhub 2 2 19428571 18731250 0 0
pwm3 0 0 18545454 102000000 0 0
pwm2 0 0 18545454 102000000 0 0
pwm1 0 0 18545454 102000000 0 0
uart_fst_mipi_cal 1 1 68000000 68000000 0 0
i2c9 1 1 81600000 83200000 0 0
i2c8 1 1 81600000 83200000 0 0
i2c7 1 1 81600000 83200000 0 0
i2c6 1 1 20400000 20700000 0 0
i2c4 1 1 20400000 20700000 0 0
i2c3 2 1 81600000 83200000 0 0
i2c2 1 1 81600000 83200000 0 0
i2c1 1 1 81600000 83200000 0 0
pllp_grtcba 0 0 408000000 408000000 0 0
pllp_xusb 0 0 408000000 408000000 0 0
pllp_grtcab 0 0 408000000 408000000 0 0
pllp_boot 0 0 408000000 408000000 0 0
pllp_grtcaa 0 0 408000000 408000000 0 0
pllp_grtlb 0 0 408000000 408000000 0 0
pllp_grtla 0 0 408000000 408000000 0 0
pllp_grtba 0 0 408000000 408000000 0 0
pllp_grtcbb 0 0 408000000 408000000 0 0
pllp_display 0 0 408000000 408000000 0 0
pllp_grttb 0 0 408000000 408000000 0 0
pllp_grtta 0 0 408000000 408000000 0 0
pllp_aon 0 0 408000000 408000000 0 0
oscillator 1 1 20000000 20000000 0 0
clk32k_in 0 0 32768 32768 0 0