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| Tektronix DPO4054 stucked at tektronix splash screen |
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| pcwrangler:
After desoldering and dumping the existing code on U822 I can see it contains more than just the bootloader. I compared it to the bootloader.img obtained via 'binwalk -e' of the latest firmware from the Tektronix website. Some fancy dd work on this might merge them, overwriting the bootloader portion to make things work but I would rather receive a U822 dump from someone else in the community so I know it is a functional copy. The results are below. binwalk of U822 dump (524KB) --- Quote ---DECIMAL HEXADECIMAL DESCRIPTION -------------------------------------------------------------------------------- 295 0x127 Unix path: /vol/ibunix01/r66tools/r66tools/mvserve/filesys 1370 0x55A U-Boot version string, "U-Boot 1.0.0 (Sep 8 2006 - 08:50:07) Tektronix, Inc. V1.02" 262144 0x40000 uImage header, header size: 64 bytes, header CRC: 0x552D426F, created: 2029-04-03 03:29:53, image size: 774975028 bytes, Data Address: 0x20284A61, Entry Point: 0x6E202038, data CRC: 0x20323030, image name: "11:12:14) Tektronix, Inc. V1.06" 262148 0x40004 U-Boot version string, "U-Boot 1.1.4 (Jan 8 2007 - 11:12:14) Tektronix, Inc. V1.06" 381312 0x5D180 CRC32 polynomial table, big endian 386984 0x5E7A8 U-Boot version string, "U-Boot 1.1.4" 414044 0x6515C Unix path: /vol/ibunix03/r66tools/r66tools/mvserve/filesys --- End quote --- binwalk of bootloader.img from Tek (262KB) --- Quote ---DECIMAL HEXADECIMAL DESCRIPTION -------------------------------------------------------------------------------- 0 0x0 uImage header, header size: 64 bytes, header CRC: 0x552D426F, created: 2029-04-03 03:29:53, image size: 774975028 bytes, Data Address: 0x20284A61, Entry Point: 0x6E202038, data CRC: 0x20323030, image name: "11:12:14) Tektronix, Inc. V1.06" 4 0x4 U-Boot version string, "U-Boot 1.1.4 (Jan 8 2007 - 11:12:14) Tektronix, Inc. V1.06" 119168 0x1D180 CRC32 polynomial table, big endian 124840 0x1E7A8 U-Boot version string, "U-Boot 1.1.4" 151900 0x2515C Unix path: /vol/ibunix03/r66tools/r66tools/mvserve/filesys --- End quote --- |
| analogRF:
looks like there are two different versions of u-boot in U822? but why? if the flash was really corrupted, I believe the chances that binwalk could extract even that much information was slim. Still it could be corrupted in just a few bytes somewhere but that is very unlikely in my view. The fact that binwalk can still extract this much info is 'probably' a sign that flash is not at fault |
| analogRF:
assuming the flash chip is ok, I think the cpu stalls when she wants to communicate with a peripheral device/chip and perhaps does not get the right response/acknowledge. At this early stage I think it is more likely to be a device on the PCI bus --- Code: ---PCI: Bus Dev VenId DevId Class Int 00 13 10b5 9056 0680 18 00 15 1002 4c59 0300 17 --- End code --- the first device is the PCI Bus Master chip made by PLX (PCI9056) and the second device in the list is the ATI Mobility Radeon graphics processor but how to troubleshoot their connection? is beyond me... :-// :scared: |
| m k:
If there is a real PCI connector its IDSEL should blink. If it does then at least the controller is alive. --- Quote from: analogRF on February 16, 2021, 10:21:11 pm ---looks like there are two different versions of u-boot in U822? but why? --- End quote --- My guess is that the older one is a backup bootloader. Something like when writing a new bootloader fails backup one is still ok. So can one think that good behaving Tek has done the same with everything? |
| pcwrangler:
--- Quote from: analogRF on February 18, 2021, 02:17:16 am ---assuming the flash chip is ok, I think the cpu stalls when she wants to communicate with a peripheral device/chip and perhaps does not get the right response/acknowledge. At this early stage I think it is more likely to be a device on the PCI bus --- Code: ---PCI: Bus Dev VenId DevId Class Int 00 13 10b5 9056 0680 18 00 15 1002 4c59 0300 17 --- End code --- the first device is the PCI Bus Master chip made by PLX (PCI9056) and the second device in the list is the ATI Mobility Radeon graphics processor but how to troubleshoot their connection? is beyond me... :-// :scared: --- End quote --- vcc and clock are good on the PCI9056 at U560 but the IDSEL(thanks m k) line is stuck low. The datasheet of this chip and the 440EP CPU show their IDSEL pins as input. Anyone know the source? BTW: I programmed the flash with the downloaded and extracted bootloader.img just to see what would happen but it wouldn't even provide a boot log, completely dead. I reprogrammed it with the original code and it's back to the previous behavior. I thought I would add this here just in case someone is playing with firmware in the future. I suppose a merge of that img file with the original code might work but I believe you all are correct; if it was damaged I wouldn't get much useful info out of it. |
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