>> 0xbe000000 is in the uncached, unmapped (no TLB) section called KSEG1. >> In KSEG1 the physical address is the same as the virtual address with >> the top 3 bits forced to 0. The MIPS boot address is in KSEG1 @ >> 0xbfc00000 > > Interesting... That means we *can* in fact reprogram the flash whenever the > bootloader is really, really ruined ? > > I have a box that have this problem: the flash is fully empty, and I can't > detect it at all. > I'll try with the above address...
I started to investigate this with an BCM4712 based system (Siemens SE505) as well. In the meantime I can read the flash area and the detectflash works as well. Haven't tried flashing itself yet, however. Commands given: ----------------------------------------------- cable arm-usb-ocd driver=ftdi-mpsse frequency 1000000 detect [messages about detecting the bcm4712 and loading the respective file] register EJIMPCODE 32 register EJADDRESS 32 register EJDATA 32 register EJCONTROL 32 register EJALL 96 register EJFASTDATA 33 instruction EJTAG_IMPCODE 00000011 EJIMPCODE instruction EJTAG_ADDRESS 00001000 EJADDRESS instruction EJTAG_DATA 00001001 EJDATA instruction EJTAG_CONTROL 00001010 EJCONTROL instruction EJTAG_ALL 00001011 EJALL instruction EJTAGBOOT 00001100 BR instruction NORMALBOOT 00001101 BR instruction EJTAG_FASTDATA 00001110 EJFASTDATA initbus ejtag detectflash 0x3fc00000 -> base address of flash in 16 bit bus area readmem 0x3fc00000 0x100 cfe.bin -> reads first 256 bytes of CFE, compare with reference data ok readmem 0x3fff8000 0x400 nvram.bin -> reads the first 1k of NVRAM, reasonable data ----------------------------------------------- If the register and instructions definitions are ok, I'd add them to the official bcm4712 description file in urjtag trunk. What is your impression here? I wasn't able to get anything useful from the ejtag_dma driver yet... Cheers Arnim ------------------------------------------------------------------------------ This SF.Net email is sponsored by the Verizon Developer Community Take advantage of Verizon's best-in-class app development support A streamlined, 14 day to market process makes app distribution fast and easy Join now and get one step closer to millions of Verizon customers http://p.sf.net/sfu/verizon-dev2dev _______________________________________________ UrJTAG-development mailing list UrJTAG-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/urjtag-development