Qualcomm Atheros IPQ8065 - Error: CPU-TAP not found in JTAG chain

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    • Qualcomm Atheros IPQ8065 - Error: CPU-TAP not found in JTAG chain

      Hi, I have a Netgear R7800 router, with erased bootloader.
      I want to get access to its memory, and upload a new firmware (or at least bootloader) to it.

      Router's hardware:
      CPU: Qualcomm Atheros IPQ8065, 1.7GHz, 2 cores
      Flash: 128 MiB (Micron MT29F1G08ABBEAH4:E)
      Architecture: ARMv7 Processor rev 0 (v7l), arm_cortex-a15_neon-vfpv4

      The problem is - IPQ8065 is not supported by default, all I got is: ****** Error: CPU-TAP not found in JTAG chain

      The Netgear firmware for this router is fully open sorce. You can get it from:
      downloads.netgear.com/files/GP….2.62_gpl_src.tar.bz2.zip
      This processor is listed as "ipq806x" in U-Boot.

      So I was thinking maybe somebody can take the processor parameters from there and add the support of it to JLink?

      I tried to add it to "JLinkDevices.xml" file, but with no luck.
      I'm new with JTAG and SEGGER, help please.

      The J-Link Commander log:

      Source Code

      1. Connecting to J-Link via USB...O.K.
      2. Firmware: J-Link V10 compiled Mar 7 2019 15:19:19
      3. Hardware version: V10.10
      4. S/N:
      5. License(s): FlashBP, GDB
      6. OEM: SEGGER-EDU
      7. VTref=1.817V
      8. Type "connect" to establish a target connection, '?' for help
      9. J-Link>connect
      10. Please specify device / core. <Default>: ARM7
      11. Type '?' for selection dialog
      12. Device>?
      13. Please specify target interface:
      14. J) JTAG (Default)
      15. TIF>j
      16. Device position in JTAG chain (IRPre,DRPre) <Default>: -1,-1 => Auto-detect
      17. JTAGConf>
      18. Specify target interface speed [kHz]. <Default>: 4000 kHz
      19. Speed>100
      20. Device "ARM7" selected.
      21. Connecting to target via JTAG
      22. TotalIRLen = 15, IRPrint = 0x0011
      23. JTAG chain detection found 2 devices:
      24. #0 Id: 0x4BA00477, IRLen: 04, CoreSight JTAG-DP
      25. #1 Id: 0x200110E1, IRLen: 11, Unknown device
      26. TotalIRLen = 15, IRPrint = 0x0011
      27. JTAG chain detection found 2 devices:
      28. #0 Id: 0x4BA00477, IRLen: 04, CoreSight JTAG-DP
      29. #1 Id: 0x200110E1, IRLen: 11, Unknown device
      30. ****** Error: CPU-TAP not found in JTAG chain
      31. TotalIRLen = 15, IRPrint = 0x0011
      32. JTAG chain detection found 2 devices:
      33. #0 Id: 0x4BA00477, IRLen: 04, CoreSight JTAG-DP
      34. #1 Id: 0x200110E1, IRLen: 11, Unknown device
      35. TotalIRLen = 15, IRPrint = 0x0011
      36. JTAG chain detection found 2 devices:
      37. #0 Id: 0x4BA00477, IRLen: 04, CoreSight JTAG-DP
      38. #1 Id: 0x200110E1, IRLen: 11, Unknown device
      39. ****** Error: CPU-TAP not found in JTAG chain
      40. Cannot connect to target.
      41. J-Link>
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      The post was edited 1 time, last by Kovur ().