Am Freitag 30 Juli 2010, 00:17:48 schrieben Sie: > On Thursday, July 29, 2010 15:35:55 Michael Walle wrote: > > there is a bug in the intel.c flash program routine. > > > > After you write CFI_INTEL_CMD_WRITE_TO_BUFFER, you are just polling the > > SR_READY in the status register. But according the the datasheet [1] > > p.24, you have to reissue the CMD_WRITE_TO_BUFFER command to let the > > status register update its SR_READY bit. > > lemme preface this with "i'm no CFI expert" ... hell, i'm not even > "adequate", but at any rate ... > > looking at say the U-Boot CFI driver, it doesnt seem to do this. instead, > it writes the command FLASH_STATUS_DONE before attempting to read back the > status word to see if SR_READY is set. and it does that in a loop. > sounds like constantly re-issuing a "write buffer" command is a bad idea. i'm looking into this tomorrow, for now im going to bed ;)
The datasheet states the following: When the Buffered Programming Setup command is issued, Status Register information is updated and reflects the availability of the buffer. SR.7 indicates buffer availability: if set, the buffer is available; if cleared, the buffer is not available. To retry, issue the Buffered Programming Setup command again, and re-check SR.7. When SR.7 is set, the buffer is ready for loading. btw, the datasheet you pointed to below, states the same (pg. 30, section 8.3). > what flash are you working with ? the only part i have ready access to is > a PC28F128P33T85, so i can test with that ... but i recall the current > driver already working. i'd have to retest real quick. > http://www.numonyx.com/Documents/Datasheets/306666_P30_Discrete_DS.pdf i'm using the JS28F256. I used it with the prototype bus driver, which was working out of the box. using the fjmem driver (with spartan6), the driver wasn't working anymore. likely to be a timing issue. in the latter case, the status register wasn't updated. -- michael ------------------------------------------------------------------------------ The Palm PDK Hot Apps Program offers developers who use the Plug-In Development Kit to bring their C/C++ apps to Palm for a share of $1 Million in cash or HP Products. Visit us here for more details: http://p.sf.net/sfu/dev2dev-palm _______________________________________________ UrJTAG-development mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/urjtag-development
