Dirk Behme wrote:
> Rick Altherr wrote:
>> The idcode IR (of jrc) is unknown
Testing all IRs, I get
-- cut --
> scan_chain
TapName | Enabled | IdCode Expected IrLen
IrCap IrMask Instr
---|--------------------|---------|------------|------------|------|------|------|---------
0 | omap3530.jrc | Y | 0x0b7ae02f | 0x0b7ae02f | 0x06 |
0x01 | 0x0f | 0x3f
1 | omap3530.cpu | n | 0x00000000 | 0xffffffff | 0x04 |
0x01 | 0x00 | 0x0f
> irscan omap3530.jrc 4
> drscan omap3530.jrc 32 0x0
0b7ae02f
>
-- cut --
jrc's ID code is at IR 4 then?
>> For any CoreSight device, the IDCODE should be obtainable by:
>>
>> irscan <tap> 0xFE
>> drscan <tap> 32 0x0
>>
>> The drscan should return the IDCODE.
>
> Testing with above 3 configurations I then did (thanks for the hint):
>
> jtag tapenable omap3530.cpu
> irscan omap3530.cpu 0xFE
> drscan omap3530.cpu 32 0x0
Some (stupid? sorry!) questions:
* In "irscan omap3530.cpu 0xFE" above: Why 0xFE ? IrLen is 0x4, so
only 16 possible addresses?
* As I understand it, by enabling omap3530.cpu, we add CoreSight
device into scan chain. This is what TI doc describes as
-- cut --
## Function : Update the JTAG preamble and post-amble counts.
Parameter : The IR pre-amble count is '0'.
Parameter : The IR post-amble count is '6'.
Parameter : The DR pre-amble count is '0'.
Parameter : The DR post-amble count is '1'.
Parameter : The IR main count is '4'.
Parameter : The DR main count is '1'
-- cut --
Where in OpenOCD code is this done? Is it done correctly?
* If I manuall access omap3530.cpu or omap3530.jrc by irscan/drscan
commands like above, the other device has to be put into bypass
automatically? E.g. doing 'irscan omap3530.jrc 4' after 'jtag
tapenable omap3530.cpu' has to put omap3530.cpu into bypass? Is this done?
E.g.
-- cut --
Open On-Chip Debugger
> irscan omap3530.jrc 4
> drscan omap3530.jrc 32 0x0
0b7ae02f
> jtag tapenable omap3530.cpu
Enabling Cortex-A8 @ OMAP3
Cortex-A8 @ OMAP3 enabled
1
> irscan omap3530.jrc 4
> drscan omap3530.jrc 32 0x0
00000000
>
-- cut --
Seems that something is "corrupted" by enabling omap3530.cpu ? Maybe
we correctly insert CoreSight device correctly into scan chain but
then fail to handle it correctly? Just an idea ;)
Best regards
Dirk
_______________________________________________
Openocd-development mailing list
[email protected]
https://lists.berlios.de/mailman/listinfo/openocd-development
