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Altera_Forum
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16 years ago

Flash Device Access

Hej

I am using my custom board where I have an external flash device attached..I want to read and write the flash device..I read the manual Nios II Software Developer's Handbook...and acording to the instructions given there..i tried to use HAL functions to open the flash drive..but i could not open the flash drive..I found tht when i tried to debug my code..and the pointer gets the value NULL even i am giving the name of flash device...correctly as I check that out in system.h file as well..i wrote like this..

alt_flash_fd* fd;

fd= alt_flash_open_dev("/dev/cfi_flash");

but after the execution of statement..fd gets 0.i.e; NULL...so the flash device doesnt opens...Can any1 please help me in this regard...

13 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    i have tried with both of these..but still the problem is there..i cant figure out where the problem can b?

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    i mean i chkd with the reduced device drivers option...and without tht option as well

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Hi,

    I think its worth trying to force it by defining the appropriate symbol as Jake has described in the referenced thread (except in your case define ALT_USE_CFI_FLASH rather than ALT_USE_EPCS_FLASH). To be on the safe side I'd then do a Clean Project before re-building. It should work.

    Cheers
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Look in the alt_sys_init.c file at the alt_sys_init() function for the ALTERA_AVALON_CFI_FLASH_INIT() function call. If it exists, then your HAL-based code is going to try to initialize the flash device. It's possible that this initialization routine is failing and your flash device isn't being registered with the HAL. You can set a break point at the call to ALTERA_AVALON_CFI_FLASH_INIT() and then step through the function to see what's happening (-O0/"Debug" optimization flags will work best).

    Another avenue to explore is how the nios2-flash-programmer "sees" this flash. To do this, load the FPGA with the SOF for the design that you're testing and then type: 

    nios2-flash-programmer --base=<base address of your flash device> --debug

    If it finds a CFI table and returns something like the following, then you're OK. Anything else, and you have issues with your flash device or your connection to/handling of it. 

    Found CFI table in 16 bit mode
Raw CFI query table read from device:
   0: 00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
  10: 00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
  20: 51 00 52 00 59 00 02 00  00 00 40 00 00 00 00 00  Q.R.Y.....@.....
  30: 00 00 00 00 00 00 27 00  36 00 00 00 00 00 07 00  ......'.6.......
  40: 07 00 0A 00 00 00 03 00  05 00 04 00 00 00 1A 00  ................
CFI query table read from device:
  10: 51 52 59 02 00 40 00 00  00 00 00 27 36 00 00 07  QRY..@.....'6...
  20: 07 0A 00 03 05 04 00 1A  02 00 05 00 01 FF 01 00  ................
  30: 02 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
CFI extended table read from device:
   0: 50 52 49 31 33 10 02 01  00 08 00 00 02 B5 C5 05  PRI13...........
  10: 01 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  ................
Read autoselect code 0001-227E (in 16 bit mode)
No CFI override data for 
Device size is 64MByte
Erase regions are:
  offset        0: 512 x 128K
Device supports AMD style programming algorithm
Multi-byte programming with 32 byte buffer
Sector erase timeout is 16s
Word program timeout is 1ms
Buffer program timeout is 4ms
Leaving target processor paused

    Oh...and welcome to the "wonderful" world of CFI "compliant" flash devices. Standards are "fun", aren't they? :-)

    Cheers,

    - Ura
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    I tried the method jake told me..to use macro...ALT_USE_CFI_FLASH...and i did build the project again..after cleaning it...but the poblem is still there...

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    and @ Ura

    i couldnt follow your instructions too much...as I am quite new to these softwares..and i did chkd the alt_sys_init.c file and there is definition of the fucntions as u said...but i couldnt figure out too much..when those fucntions run..on debugger the handler gets null value..i couldnt get too much how the funtions work inside that file...but after the statement..it gets NULL value...

    i am not sure..how to do the thing u told in the second part of the reply...can u please explain some detail how to do tht..

    thanks alot for ur time...and help....
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Read the Nios II Flash Programmer User's Guide and you'll see what I mean. I think there's even a "debug/troubleshooting" appendix at the end of it.

    HINT: Use Altera's site search to find things of this sort.

    Cheers,

    - Ura
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Hej Ura!

    I tried to boot the processor from the flash and tried to program the flash using flash programmer..but i got this kind of error..

    Using cable "USB-Blaster [USB-0]", device 1, instance 0x00

    Resetting and pausing target processor: OK

    No CFI table found at address 0x03000000

    Leaving target processor paused

    So then i tried the CLI for the nios flash programmer..and tried the debug option as well..and got the reply where there are some hex values..at differnt locations wrote into the flash..the manual says that i have to compare the values with the datasheet...which i did...and if i am thinking right...tht we have to just compare the values...i guesss the values were different....like after flash programing..value at location 10 was 33H where as in datasheet it was 51H...I am using AM29LV128M flash..which is i guess the altera supported device..
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    and its differnt in each and every entry....and also..when i tried the --debug option....it was saying like this...

    Using cable "USB-Blaster [USB-0]", device 1, instance 0x00

    Resetting and pausing target processor: OK

    No CFI table found at address 0x03000000

    Original contents <after writing 0xF0 and 0xFF to address 0x3000000):

    "values at the lcoations"

    Leaving target processor paused.