[Shield Android TV General] yahoo2016:
It's shooting in the dark without serial console. Serial console output should show if cboot is loaded by the first stage boot loader as shown in the following for SATV:

=~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2016.07.30 18:53:46 =~=~=~=~=~=~=~=~=~=~=~=
[0000.779] [TegraBoot] (version 24.00.2015.42-foster-mobile-f5e1d750)
[0000.785] Processing in cold boot mode Bootloader 2
[0000.790] A01Q Bootrom Patch rev = 3
[0000.793] Power-up reason: on button
[0000.796] No Battery Present
[0000.799] PMU BoardId: 2530
[0000.802] Platform has Ddr4 type ram
[0000.805] max77620 disabling SD1 Remote Sense
[0000.809] Setting Ddr voltage to 1125mv
[0000.814] Serial Number of Pmic Max77663: 0x1015a3
[0000.821] Entering ramdump check
[0000.824] Get RamDumpCarveOut = 0xfcf00000
[0000.828] RamDumpCarveOut=0xfcf00000, RamDumperFlag=0xffffffff
[0000.834] Last reboot was clean, booting normally!
[0000.838] Sdram initialization is successful
[0000.843] Tsec Carveout Base=0x0fe000000 Size=0x002000000
[0000.848] Lp0 Carveout Base=0x0fdfff000 Size=0x000001000
[0000.853] SecureOs Carveout Base=0x0fd600000 Size=0x000800000
[0000.859] BpmpFw Carveout Base=0x0fd500000 Size=0x000100000
[0000.864] GSC1 Carveout Base=0x0fd400000 Size=0x000100000
[0000.869] GSC2 Carveout Base=0x0fd300000 Size=0x000100000
[0000.874] GSC3 Carveout Base=0x0fd200000 Size=0x000100000
[0000.880] GSC4 Carveout Base=0x0fd100000 Size=0x000100000
[0000.885] GSC5 Carveout Base=0x0fd000000 Size=0x000100000
[0000.911] RamDump Carveout Base=0x0fcf00000 Size=0x000100000
[0000.916] Platform-DebugCarveout: 0
[0000.920] Nck Carveout Base=0x0fcd00000 Size=0x000200000
[0000.969] Using GPT Primary to query partitions
[0000.974] Loading Tboot-CPU binary
[0000.984] Verifying bootloader in SecurePKC mode
[0000.989] Bootloader load address is 0xa0000000, entry address is 0xa0000258
[0000.999] Bootloader downloaded successfully.
[0001.003] Downloaded Tboot-CPU binary to 0xa0000258
[0001.007] PMU BoardId: 2530
[0001.010] MAX77620_GPIO1 Configured: 2530
[0001.015] MAX77620_GPIO5 Configured: 2530
[0001.019] CPU power rail is up
[0001.021] CPU clock enabled
[0001.025] Performing RAM repair
[0001.028] Updating A64 Warmreset Address to 0xa00002e9
[0001.033] Bootloader DTB Load Address: 0x83000000
[0001.038] Loading Kernel DTB forcefully, ignoring RP1
[0001.073] Kernel DTB Load Address: 0x83080000
[0001.079] Loading cboot binary
[0001.128] Verifying bootloader in SecurePKC mode
[0001.155] Bootloader load address is 0x92c00000, entry address is 0x92c00258
[0001.164] Bootloader downloaded successfully.
[0001.220] Next binary entry address: 0x92c00258
[0001.225] BoardId: 2530
[0001.250] NvTbootI2cWrite(): error code 0x00045100 Error while starting write transaction
[0001.257] NvTbootI2cDeviceRead(): error code 0x00045001 Error while sending the offset to slave
[0001.266] NvTbootI2c: Read failed for slave 0xa2, offset 0x00 with error code 0x00045001
[0001.274] Display board id read failed
[0001.277] dram memory type is 3
[0001.287] WB0 init successful
[0001.314] Bpmp FW successfully loaded
[0001.317] Set NvDecSticky Bits
[0001.320] GSC1 address : fd400000
[0001.323] GSC2 address : fd300000
[0001.326] GSC3 address : fd200000
[0001.330] GSC4 address : fd100000
[0001.333] GSC5 address : fd000000
[0001.336] GSC MC Settings done
[0001.501] Secure Os PKC Verification Success.
[0001.506] Loading and Validation of Secure OS Successful
[0001.521] NvTbootPackSdramParams: start.
[0001.526] NvTbootPackSdramParams: done.
[0001.530] Starting CPU & Halting co-processor

64bWelcome to TLK

TLK initialization complete. Jumping to non-secure world
[0001.703]
[0001.704] Debug Init done
[0001.706] Marked DTB cacheable
[0001.709] Bootloader DTB loaded at 0x83000000
[0001.715] Marked DTB cacheable
[0001.718] Kernel DTB loaded at 0x83080000
[0001.722] DeviceTree Init done
[0001.737] Pinmux applied successfully
[0001.743] gicd_base: 0x50041000
[0001.747] gicc_base: 0x50042000
[0001.750] Interrupts Init done
[0001.755] Using base:0x60005008 & irq:33 for tick-timer
[0001.760] Using base:0x60005000 for delay-timer
[0001.765] platform_init_timer: DONE
[0001.768] Timer(tick) Init done
[0001.773] osc freq = 38400 khz
[0001.776]
[0001.777] welcome to cboot
[0001.780]
[0001.781] Cboot Version: 24.00.2015.42-foster-t210-b26a161f
[0001.787] calling constructors
[0001.790] initializing heap
[0001.792] initializing threads
[0001.795] initializing timers
[0001.798] creating bootstrap completion thread
[0001.803] top of bootstrap2()