[PATCH] AT91RM9200 NAND support

Savin Zlobec savin at epico.si
Tue Jun 20 09:48:20 EDT 2006


Thomas Gleixner wrote:

>This gets even more mysterious. I both cases the previous function was
>nand_wait(), which blocks in the wait function until ready state is
>reached. 
>
>I really have no clue, how the chip gets into busy state between the
>return from nand_wait() and the next commmand. 
>
>Is there anything playing with the enable pin of the nand chip between
>those commands ? Those chips have an autoread feature on power on. Is
>the power switched off ?
>  
>
No.

>Have you any other modifications to at91_nand.c I'm not aware of ?
>  
>
No.

I've pinpointed the location to the command switch at the end of 
nand_command fn:

        switch (command) {

        case NAND_CMD_PAGEPROG:
        case NAND_CMD_ERASE1:
        case NAND_CMD_ERASE2:
        case NAND_CMD_SEQIN:
        case NAND_CMD_STATUS:
                chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE);
^^^^^^^^^^^^^
if I wait for ready at this point then I can copy files to jffs2 
partition on my
nand without problems (...well as far as I can tell from a short test...).

savin





More information about the linux-mtd mailing list