Hi Dave, On 1/23/10, David Brownell <davi...@pacbell.net> wrote: > On Monday 18 January 2010, Alan Carvalho de Assis wrote: > >> When I type halt the prompt get blocked and about 1 minute after I >> receive this error: >> >> > halt >> AHBAP Cached values: dp_select 0x10, ap_csw 0xa2000002, ap_tar 0x54011080 >> JTAG-DP OVERRUN - check clock or reduce jtag speed >> Read MEM_AP_CSW 0x80000042, MEM_AP_TAR 0x54011080 >> >> I already reduced the jtag speed to 500khz and this error remain. >> >> What could I investigate now to fix this error? > > Unfortunately I think you're starting to hit some of the ways > that the DAP code is ... a bit flakey. Especially with respect > to how it handles errors reported by the DP or AP; it triggers > faults a bit more often (and randomly) than I would expect, and > the cleanup -- and mode selection -- looks a bit iffy to me. > > I attach a couple patches which I've been using, which might > change things (or might not). If they help, good. > > - adi-shrink.patch ... code shrinkage and fault path fixes > > - adi-write.patch ... goes over that, basically just cleanup > > If not, then there's something else you could build on top > of these. Basically, after adi-shrink.patch there is ONE > "REVISIT" comment about putting the memaccess_tck cycles in > the proper place. Fix that issue -- just put those cycles > at the end of adi_jtag_dp_scan() not the beginning, after > the jtag_add_dr_scan(). (Before that patch, that was done > wrong in *two* places.) >
It doesn't work. Even I putting the memaccess_tck cycles after adi_jtag_dp_scan() I still getting the same error: $ telnet 127.0.0.1 4444 Trying 127.0.0.1... Connected to 127.0.0.1. Escape character is '^]'. Open On-Chip Debugger > reset JTAG tap: imx51.DAP tap/device found: 0x1ba00477 (mfg: 0x23b, part: 0xba00, ver: 0x1) TAP imx51.SDMA does not have IDCODE JTAG tap: imx51.SJC tap/device found: 0x1190c01d (mfg: 0x00e, part: 0x190c, ver: 0x1) imx51.cpu: how to reset? Command handler execution failed in procedure 'reset' called at file "command.c", line 647 called at file "command.c", line 361 > halt AHBAP Cached values: dp_select 0x10, ap_csw 0xa2000002, ap_tar 0x54011080 JTAG-DP OVERRUN - check clock or reduce jtag speed Read MEM_AP_CSW 0x80000042, MEM_AP_TAR 0x54011080 > The OVERRUN error comes from throwing data at the MEM-AP > faster than it can handle it. MEM-AP speed is a system > specific issue. Exactly the sort of thing MX51 could very > reasonably do differently from the other Cortex parts which > now mostly work. (I'm not quite clear on how much of that > is driven by the JTAG clock vs by whatever core clock your > chip may be using.) There are two issues I'd wonder about: > > * First, whether the code is correct ... ergo the > attached patches and that REVISIT comment. > > * Second, whether you need a different memaccess_tck > value. > > The ADIv5 spec will be useful to sort out such issues. > I tested memaccess_tck with small values as 8, 80, 100 and big values as 100000. In all tests it returns same error message above. I just noticied it delay a little more time to show this error msg when I use 100000. Best Regards, Alan _______________________________________________ Openocd-development mailing list Openocd-development@lists.berlios.de https://lists.berlios.de/mailman/listinfo/openocd-development
