Attached patch allows isolinux to boot from a CDROM attached to a NCR/Symbios/LSIlogic SCSI controller (bios version 4.19). It appears this bios can't read more than 1 sector at the time using the ah=42h int13 call. The isolinux boot was failing early on when 4 sector are read. (bios returned error 0 !) I'm not sure if the same 'getlinsec' routine is called upon later to load the images selected by the user otherwise, for the 4 sector read, this change shouldn't have much impact on other systems. (boot speed was very fast). Regards, Ruud L. --- isolinux.asm.ORIG Sat Jun 1 09:52:41 2002 +++ isolinux.asm Sun Jun 2 14:14:12 2002 @@ -498,9 +498,9 @@ mov [si+8],eax .loop: push bp ; Sectors left - cmp bp,byte 32 + cmp bp,byte 1 ; 1 works for LSIlogic jbe .bp_ok - mov bp,32 + mov bp,1 .bp_ok: mov [si+2],bp push si
H. Peter Anvin
2002-Jun-02 19:27 UTC
[syslinux] PATCH for Symbios/LSIlogic scsi and isolinux
Ruud wrote:> Attached patch allows isolinux to boot from a CDROM attached to > a NCR/Symbios/LSIlogic SCSI controller (bios version 4.19). > > It appears this bios can't read more than 1 sector at the time using > the ah=42h int13 call. The isolinux boot was failing early on when > 4 sector are read. (bios returned error 0 !) > > I'm not sure if the same 'getlinsec' routine is called upon later to > load the images selected by the user otherwise, for the 4 sector read, > this change shouldn't have much impact on other systems. > (boot speed was very fast). >Good GOD! This is just insane... CD-ROM BIOS with floppy-BIOS bugs... and returning error with no error code. Really makes you wonder what the heck these people are smoking. I might try to port the weird adaptive algorithm I started using for floppies. Would you mind trying it out once I get done? -hpa> Regards, > Ruud L. > > --- isolinux.asm.ORIG Sat Jun 1 09:52:41 2002 > +++ isolinux.asm Sun Jun 2 14:14:12 2002 > @@ -498,9 +498,9 @@ > mov [si+8],eax > .loop: > push bp ; Sectors left > - cmp bp,byte 32 > + cmp bp,byte 1 ; 1 works for LSIlogic > jbe .bp_ok > - mov bp,32 > + mov bp,1 > .bp_ok: > mov [si+2],bp > push si > _______________________________________________ > SYSLINUX mailing list > Submissions to SYSLINUX at zytor.com > Unsubscribe or set options at: > http://www.zytor.com/mailman/listinfo/syslinux