Hi,
We've been trying to communicate via JTAG (through a signalyzer H2)
with a freescale 568013.
Modifying the code for the dsp56321 we were able to communicate with
our chip. It has two taps, a MASTER tap and a CORE tap.
The default tap is the MASTER tap, and by default the CORE tap is
disabled. There is a command to switch from the MASTER tap to the CORE
tap and vice versa. Since it is a switch, only ONE tap is connected at
a time.
We need to make openocd know that the command that switches from
MASTER to CORE disables MASTER (and the command to switch from CORE to
MASTER disables CORE).
The config file (see below) shows the hack we are currently using
(empty disable functions).
#-----------------------------------------------------------------
#-----------------------------------------------------------------
# Script for freescale DSP568013
#
source [find interface/signalyzer-h2.cfg]
if { [info exists CHIPNAME] } {
set _CHIPNAME $CHIPNAME
} else {
set _CHIPNAME dsp568013
}
if { [info exists ENDIAN] } {
set _ENDIAN $ENDIAN
} else {
# this defaults to a big endian
set _ENDIAN big
}
if { [info exists CPUTAPID ] } {
set _CPUTAPID $CPUTAPID
} else {
# force an error till we get a good number
set _CPUTAPID 0x01f2801d
}
#jtag speed
adapter_khz 10
#has only trst
reset_config trst_only
#MASTER tap
jtag newtap $_CHIPNAME chp -irlen 8 -ircapture 1 -irmask 0x03
-expected-id $_CPUTAPID
#CORE tap
jtag newtap $_CHIPNAME cpu -irlen 4 -ircapture 1 -irmask 0x03 -disable
-expected-id 0x02211004
#target configuration
set _TARGETNAME $_CHIPNAME.cpu
#target create $_TARGETNAME dsp5680xx -endian $_ENDIAN -chain-position
$_TARGETNAME
#select CORE tap by modifying the TLM register.
#to be used when MASTER tap is selected.
jtag configure $_TARGETNAME -event tap-enable "
irscan $_CHIPNAME.chp 0x05;
drscan $_CHIPNAME.chp 4 0x02;
jtag tapdisable $_CHIPNAME.chp;
"
#select MASTER tap by modifying the TLM register.
#to be used when CORE tap is selected.
jtag configure $_CHIPNAME.chp -event tap-enable "
irscan $_TARGETNAME 0x4;
drscan $_TARGETNAME 4 0x1;
jtag tapdisable $_TARGETNAME;
"
jtag configure $_TARGETNAME -event tap-disable {
}
jtag configure $_CHIPNAME.chp -event tap-disable {
}
#working area at base of ram
#$_TARGETNAME configure -work-area-virt 0
#-----------------------------------------------------------------
#-----------------------------------------------------------------
The tap seems to switch. After switching we can get what we believe is
the CORE tap's IDCODE by executing:
> scan_chain
TapName Enabled IdCode Expected IrLen IrCap IrMask
-- ------------------- -------- ---------- ---------- ----- ----- ------
0 dsp568013.chp Y 0x01f2801d 0x01f2801d 8 0x01 0x03
1 dsp568013.cpu n 0x00000000 0x02211004 4 0x01 0x03
> jtag tapenable dsp568013.cpu
JTAG tap: dsp568013.chp disabled
JTAG tap: dsp568013.cpu enabled
1
> scan_chain
TapName Enabled IdCode Expected IrLen IrCap IrMask
-- ------------------- -------- ---------- ---------- ----- ----- ------
0 dsp568013.chp n 0x01f2801d 0x01f2801d 8 0x01 0x03
1 dsp568013.cpu Y 0x00000000 0x02211004 4 0x01 0x03
> irscan dsp568013.cpu 0x2
> drscan dsp568013.cpu 32 0
02211004
>
Switching back to the MASTER tap does not seem to work correctly.
After switching to the CORE tap and back to the MASTER tap we cannot
execute IDCODE successfully.
We get the following on telnet:
> jtag tapenable dsp568013.chp
JTAG tap: dsp568013.cpu disabled
JTAG tap: dsp568013.chp enabled
1
> irscan dsp568013.chp 0x02
> drscan dsp568013.chp 32 0
00000000
> drscan dsp568013.chp 32 0
00000000
> drscan dsp568013.chp 32 2
00000004
looks like the tap is working in BYPASS. if we run "pathmove RESET"
everything works fine again:
> pathmove RESET
> irscan dsp568013.chp 0x02
> drscan dsp568013.chp 32 0
01F2801D
What is the correct way to do the switching?
Also, is there any way to get irscan to show what was shifted in?
Thanks!
--
Rodrigo.
_______________________________________________
Openocd-development mailing list
[email protected]
https://lists.berlios.de/mailman/listinfo/openocd-development
