BIOS signature recovery??
juanba
juanba at suinsa.com
Fri Oct 25 09:38:55 EDT 2002
Playing with a Milenium DOC/ mts Linux tools i have lost the magic
number 0x55aa.
Howto recovery the stuff ?
I am using directly the interface WriteDOC but it doesn't work.
Is there any quick DOC register map/scheme reference guide?
Are their some kinda ronly register?
The device is really good, in fact is already ext2 formatted and it can
be mounted for r/w operations. I have hack the docprobe stuff adding
some interface/control for the detection and so on but i wanna have also
an extra module parameter to recover the BIOS word.
#ifdef CONFIG_MTD_DOCPROBE_55AA
/* Check for 0x55 0xAA signature at beginning of window,
this is no longer true once we remove the IPL (for Millennium */
o_1 = ReadDOC( window, Sig1 );
o_2 = ReadDOC( window, Sig2 );
b_sig_lost = ( o_1 != 0x55 || o_2 != 0xaa );
if( b_sig_lost ){
if( !doc_config_location )
return 0;
printk( KERN_WARNING "docprobe: signature lost? $%02x/$%02x\n",
o_1, o_2 );
printk( KERN_WARNING "docprobe: OK. We trust you ;-)\n");
}
#endif /* CONFIG_MTD_DOCPROBE_55AA */
#ifndef DOC_PASSIVE_PROBE
/* It's not possible to cleanly detect the DiskOnChip - the
* bootup procedure will put the device into reset mode, and
* it's not possible to talk to it without actually writing
* to the DOCControl register. So we store the current contents
* of the DOCControl register's location, in case we later decide
* that it's not a DiskOnChip, and want to put it back how we
* found it.
*/
tmp2 = ReadDOC(window, DOCControl);
/* Reset the DiskOnChip ASIC */
WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
window, DOCControl);
WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
window, DOCControl);
/* Enable the DiskOnChip ASIC */
WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
window, DOCControl);
WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
window, DOCControl);
#endif /* !DOC_PASSIVE_PROBE */
if( b_sig_lost && doc_recovery ){
WriteDOC( 0x55, window, Sig1 );
WriteDOC( 0xaa, window, Sig2 );
o_1 = ReadDOC( window, Sig1 );
o_2 = ReadDOC( window, Sig2 );
b_sig_lost = ( o_1 != 0x55 || o_2 != 0xaa );
if( b_sig_lost )
printk(KERN_WARNING "docprobe: signature recovery: FAILs\n");
printk( KERN_WARNING "docprobe: [ $%02x/$%02x ][ $%02x/$%02x ]\n",
0x55, 0xaa, o_1, o_2 );
}
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