Re: [OpenOCD-user] Advice on Snapdragon 820

[Sergei A. <sa...@gm...>]

On 5 January 2017 at 10:11, Matthias Welwarsky <mat...@we...> wrote:
> Hello Sergei,
>
> On Thursday 05 January 2017 01:25:35 Sergei Antonov wrote:
>> Hello!
>> I'd like to use OpenOCD with a development board containing a Qualcomm
>> Snapdragon 820 (APQ8096) processor, its architecture is AArch64. Here
>> is the scanned JTAG chain:
>>
>> Info : JTAG tap: auto0.tap tap/device found: 0x5ba00477 (mfg: 0x23b
>> (ARM Ltd.), part: 0xba00, ver: 0x5)
>> Info : JTAG tap: auto1.tap tap/device found: 0x000016dd (mfg: 0x36e
>> (Certicom Corporation), part: 0x0001, ver: 0x0)
>> Info : JTAG tap: auto2.tap tap/device found: 0x4003e0e1 (mfg: 0x070
>> (Qualcomm), part: 0x003e, ver: 0x4)
>>
>> I suppose, I can debug device 0x5ba00477 as aarch64 target using
>> development source code. What repo/branch of OpenOCD should I use?
>> On Gerrit there are lots of patches for aarch64, I'm confused about
>> what exactly is state-of-the-art or has best chances to work on my
>> hardware.
>
> If you checkout http://openocd.zylin.com/#/c/3832, you get a pretty good base
> for aarch64 debugging. You will also likely need this patch:
>
> http://openocd.zylin.com/#/c/3710 on top, you should be able to cherry-pick
> it.

Thanks, Matthias! I took c/3832, cherry-picked changes from c/3710,
and added -ignore-syspwrupack to my .cfg. Unfortunately, target
examination fails. Details are below.

== openocd.cfg ==
source [find interface/altera-usb-blaster.cfg]
jtag newtap auto0 tap -irlen 4 -expected-id 0x5ba00477 -ignore-syspwrupack
jtag newtap auto1 tap -irlen 5 -expected-id 0x000016dd
jtag newtap auto2 tap -irlen 11 -expected-id 0x4003e0e1
target create target0 aarch64 -endian little -chain-position auto0.tap
init

== Relevant part of debug output ==
Debug: 193 21 core.c:1399 jtag_init_inner(): Init JTAG chain
Debug: 194 21 core.c:327 jtag_call_event_callbacks(): jtag event: TAP reset
Debug: 195 21 core.c:1060 jtag_examine_chain(): DR scan interrogation
for IDCODE/BYPASS
Debug: 196 21 core.c:327 jtag_call_event_callbacks(): jtag event: TAP reset
Info : 197 29 core.c:959 jtag_examine_chain_display(): JTAG tap:
auto0.tap tap/device found: 0x5ba00477 (mfg: 0x23b (ARM Ltd.), part:
0xba00, ver: 0x5)
Info : 198 29 core.c:959 jtag_examine_chain_display(): JTAG tap:
auto1.tap tap/device found: 0x000016dd (mfg: 0x36e (Certicom
Corporation), part: 0x0001, ver: 0x0)
Info : 199 29 core.c:959 jtag_examine_chain_display(): JTAG tap:
auto2.tap tap/device found: 0x4003e0e1 (mfg: 0x070 (Qualcomm), part:
0x003e, ver: 0x4)
Debug: 200 29 core.c:1190 jtag_validate_ircapture(): IR capture validation scan
Debug: 201 34 core.c:1248 jtag_validate_ircapture(): auto0.tap: IR capture 0x01
Debug: 202 34 core.c:1248 jtag_validate_ircapture(): auto1.tap: IR capture 0x01
Debug: 203 34 core.c:1248 jtag_validate_ircapture(): auto2.tap: IR capture 0x1
Debug: 204 34 openocd.c:148 handle_init_command(): Examining targets...
Debug: 205 34 target.c:1513 target_call_event_callbacks(): target
event 21 (examine-start)
Debug: 206 34 arm_adi_v5.c:603 dap_dp_init():
Debug: 207 34 arm_adi_v5.c:636 dap_dp_init(): DAP: wait CDBGPWRUPACK
Debug: 208 34 arm_adi_v5.h:432 dap_dp_poll_register(): DAP: poll 4,
mask 0x20000000, value 0x20000000
Debug: 209 135 arm_adi_v5.c:789 dap_find_ap(): Found APB-AP at AP
index: 1 (IDR=0x44770002)
Debug: 210 173 adi_v5_jtag.c:572 jtagdp_transaction_endcheck():
jtag-dp: CTRL/STAT 0x70000021
Error: 211 173 adi_v5_jtag.c:584 jtagdp_transaction_endcheck():
JTAG-DP STICKY ERROR
Error: 212 178 aarch64.c:1825 aarch64_examine_first(): Could not
initialize the APB-AP
Debug: 213 178 openocd.c:150 handle_init_command(): target examination failed