Re: [PPCBoot-users] Question about 8250+BDI behavior..

SourceForge Headquarters 225 Broadway Suite 1600 San Diego, CA 92101 +1 (858) 454-5900

This sounds a lot like the CPM clocking errata.  We were using a 8260 with 
2.5x clocking and it would sort of work, but when we hit it with some 
ethernet traffic, the CPM would write garbage on its internal parameter 
memory, causing it to fetch bogus memory addresses which, in turn caused 
the system to lock up due to a memory access exception.  Let me tell you, 
that drove us CRAZY!

gvb

http://e-www.motorola.com/brdata/PDFDB/docs/MPC8260CE.pdf

CPM 62. THE CPM PLL DOES NOT LOCK RELIABLY FOR CERTAIN
MULTIPLICATION FACTORS.

If the CPM multiplication factor is 2.5, 3.5, 5 or 6 the internal PLL will 
not lock reliably which will result in erratic behavior. Sometimes (mainly 
at bus frequencies lower than 50 Mhz) it might lock, however it might loose 
the lock after worth. If one of the other multiplication factors (2,3 or 4) 
is selected, the CPM PLL will lock reliably, even at 66 Mhz bus speed.

Workaround: Do not use the non-reliable multiplication factors. For 166 Mhz 
CPM use 55 Mhz bus frequency and a CPM multiplication factor of 3.

At 11:31 PM 11/12/2002 -0500, ke...@ca... wrote:
>Hello list!
>
>I've checked the archives, but have not found anyone using the 8250 with
>   PPCboot or the BDI..
>
>I have one quick question for you.. I have a board with an 8250 cpu.
>It's a HIP4 Mask A.0 2K25A.  This board works fine with an 8265 cpu on
>it but exhibits strange behavoir with the 8250..
>
>The board boots and runs fine when connected to the BDI-2000, however
>when I try to run the board without the BDI connected, the board usually
>hangs when trying to set up serial communications on the CPM. It will
>try to read from invalid addresses, it will have Unknown exceptions.
>Just weird behavior.
>
>I know you're thinking that there's something in the BDI config file
>that I'm not setting up right in PPCBoot, but I don't think so. All my
>config file does is set the MSR to 00000040 to clear it and set the
>SYPCR to FFFFFFC3 for the watchdog timer. This is done in PPCBoot.
>
>If I plug the BDI into the board, power on the board and pull the BDI
>connector off the second that the BDI displays it's first message
>"Processing power-up delay", when I pull the BDI connector off, the
>board boots perfectly fine without fail.
>This leads me to believe that the BDI is asserting some signals or
>running some instructions but i don't know what.
>
>Termination on the COP port is as follows..
>
>10k pull-ups on the COP_TCK, COP_TMS, /CKSTP_OUT, /QREQ, /TRST, and
>/TRIS. 1k pull-ups on the /SRESET and /CPU_HRST and a 10k pull-down on
>COP_TDI.
>
>Here is all my BDI config file is..
>
>
>[INIT]
>WREG    MSR             0x00000040      ; clear MSR
>WM32    0xF0010004      0xFFFFFFC3      ; SYPCR == no watchdog
>
>[TARGET]
>CPUTYPE     8260        ;the CPU type (603EV,750,8240,8260)
>JTAGCLOCK   0           ;use 16 MHz JTAG clock
>BDIMODE     AGENT       ;the BDI working mode (LOADONLY | AGENT | GATEWAY)
>BREAKMODE   HARD        ;SOFT or HARD, HARD uses PPC hardware breakpoints
>VECTOR      NOCATCH       ;catch unhandled exceptions
>DCACHE      NOFLUSH     ;data cache flushing (FLUSH | NOFLUSH)
>MMU         XLAT 0xc0000000
>PTBASE      0x000000f0
>
>[FLASH]
>CHIPTYPE    AM29BX16       ;Flash type (AM29F | AM29BX8 | AM29BX16 |
>I28BX8 | I28BX16)
>CHIPSIZE    0x200000    ;The size of one flash chip in bytes (e.g.
>AM29F010 = 0x20000)
>BUSWIDTH    16           ;The width of the flash memory bus in bits (8 |
>16 | 32 | 64)
>
>
>[HOST]
>IP      192.168.254.42
>FILE    main.elf
>FORMAT  ELF
>LOAD    MANUAL          ;load code MANUAL or AUTO after reset
>
>[REGS]
>DMM1    0xF0000000
>FILE    reg8260.def
>
>
>Any advice, comments, flames are welcome. :)
>
>Kevin Fry
>
>
>
>
>
>-------------------------------------------------------
>This sf.net email is sponsored by: Are you worried about
>your web server security? Click here for a FREE Thawte
>Apache SSL Guide and answer your Apache SSL security
>needs: http://www.gothawte.com/rd523.html
>_______________________________________________
>PPCBoot-users mailing list
>PPC...@li...
>https://lists.sourceforge.net/lists/listinfo/ppcboot-users

**********************************************************************
This e-mail and any files transmitted with it are confidential and may
be legally privileged or otherwise exempt from disclosure under
applicable law. This e-mail and its files are intended solely for
the individual or entity to whom they are addressed and their content
is the property of Smiths Aerospace.  If you are not the intended
recipient, please do not read, copy, use or disclose this communication.
If you have received this e-mail in error please notify the e-mail 
administrator at pos...@si... and then delete this e-mail, its
files and any copies.

This footnote also confirms that this e-mail message has been scanned
for the presence of known computer viruses.
***********************************************************************