【MPSOC-P5问题记录】使用JTAG下载uboot时下载失败

lolikon.

跟着MPSOC-P5的手册12.2.3 使用JTAG下载到开发板上，出现如下报错。

$ petalinux-boot --jtag --fpga --u-boot
INFO: Sourcing build tools
INFO: Use bitstream: "/home/Workspace_Disk/Workspace/myyocto/images/linux/system.bit.
INFO: Please use --fpga --bitstream <BITSTREAM> to specify a bitstream if you want to use other bitstream.
INFO: Launching XSDB for file download and boot.
INFO: This may take a few minutes, depending on the size of your image.
rlwrap: warning: your $TERM is 'xterm-256color' but rlwrap couldn't find it in the terminfo database. Expect some problems.: Inappropriate ioctl for device
INFO: Configuring the FPGA...                                                                  
INFO: Downloading bitstream: /home/Workspace_Disk/Workspace/myyocto/images/linux/system.bit to the target.
INFO: Downloading ELF file: /home/Workspace_Disk/Workspace/myyocto/images/linux/pmufw.elf to the target.
INFO: Downloading ELF file: /home/Workspace_Disk/Workspace/myyocto/images/linux/zynqmp_fsbl.elf to the target.
INFO: Loading image: /home/Workspace_Disk/Workspace/myyocto/images/linux/system.dtb at 0x00100000 INFO: Downloading ELF file: /home/Workspace_Disk/Workspace/myyocto/images/linux/u-boot.elf to the target.
Memory write error at 0x8051F00. Invalid DAP ACK value: 0                                             
    invoked from within
"::tcf::eval -progress {
            apply {{info} {
                if { $::xsdb::silent_mode == 0 } {
                    switch -- [lindex $info 0] {
                        "info" {
                            puts -nonewline "\r[lindex $info 1]"
                        }
                        "warning" {
                            puts "\n[lindex $info 1]"
                        }
                        "data" {
                            puts -nonewline "\r[lindex $info 1] of [lindex $info 2] complete"
                        }
                        "done" {
                            puts "\n[lindex $info 1]"
                        }
                    }
                    flush stdout                                                                     
                }
                ::xsdb::abort_check
            }}} {::tcf::cache_enter tcfchan#0 {tcf_cache_eval {download_cache_client ::tcfclient#0::arg}}}"
    (procedure "::tcf::cache_eval_with_progress" line 2)
    invoked from within
"::tcf::cache_eval_with_progress $params(chan) [list download_cache_client $argvar] {
            apply {{info} {
                if { $::xsdb::silent_mode == 0 } {
                    s..."
    (procedure "dow" line 99)
    invoked from within
"dow  "/home/Workspace_Disk/Workspace/myyocto/images/linux/u-boot.elf""                           
    (file "/tmp/tmp.LusGsNCt6C" line 33)

INFO: The XSDB log is as follows
attempting to launch hw_server

****** Xilinx hw_server v2020.2
  **** Build date : Nov  8 2020 at 18:16:39
    ** Copyright 1986-2020 Xilinx, Inc. All Rights Reserved.

INFO: hw_server application started
INFO: Use Ctrl-C to exit hw_server application

INFO: To connect to this hw_server instance use url: TCP:127.0.0.1:3121

根据这个“Memory write error at 0x8051F00. Invalid DAP ACK value: 0”的报错，很有可能是JTAG通信不稳定导致。
我自己做了如下尝试：
1、把VMware的USB兼容性设置为USB 3.1 。（自己玩HACKRFONE的时候要设置2.0才能成功连上就一直设置了2.0。。。）
2、JTAG直接接到主板的USB接口上， 跳过了一堆拓展坞。
3、原本想换个JTAG试试，买回来后才发现跟原子哥的jtag接口定义不一样hhhh。幸好花的不是自己的money hhh。

下载成功率从0%变成了95%。虽然不稳定，但至少是能用吧。。。