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-rw-r--r--drivers/ide/legacy/hd.c73
1 files changed, 12 insertions, 61 deletions
diff --git a/drivers/ide/legacy/hd.c b/drivers/ide/legacy/hd.c
index 7f4c0a5050a1..8f2db8dd35f7 100644
--- a/drivers/ide/legacy/hd.c
+++ b/drivers/ide/legacy/hd.c
@@ -719,74 +719,25 @@ static int __init hd_init(void)
719 device_timer.function = hd_times_out; 719 device_timer.function = hd_times_out;
720 blk_queue_hardsect_size(hd_queue, 512); 720 blk_queue_hardsect_size(hd_queue, 512);
721 721
722#ifdef __i386__
723 if (!NR_HD) { 722 if (!NR_HD) {
724 extern struct drive_info drive_info; 723 /*
725 unsigned char *BIOS = (unsigned char *) &drive_info; 724 * We don't know anything about the drive. This means
726 unsigned long flags;
727 int cmos_disks;
728
729 for (drive=0 ; drive<2 ; drive++) {
730 hd_info[drive].cyl = *(unsigned short *) BIOS;
731 hd_info[drive].head = *(2+BIOS);
732 hd_info[drive].wpcom = *(unsigned short *) (5+BIOS);
733 hd_info[drive].ctl = *(8+BIOS);
734 hd_info[drive].lzone = *(unsigned short *) (12+BIOS);
735 hd_info[drive].sect = *(14+BIOS);
736#ifdef does_not_work_for_everybody_with_scsi_but_helps_ibm_vp
737 if (hd_info[drive].cyl && NR_HD == drive)
738 NR_HD++;
739#endif
740 BIOS += 16;
741 }
742
743 /*
744 We query CMOS about hard disks : it could be that
745 we have a SCSI/ESDI/etc controller that is BIOS
746 compatible with ST-506, and thus showing up in our
747 BIOS table, but not register compatible, and therefore
748 not present in CMOS.
749
750 Furthermore, we will assume that our ST-506 drives
751 <if any> are the primary drives in the system, and
752 the ones reflected as drive 1 or 2.
753
754 The first drive is stored in the high nibble of CMOS
755 byte 0x12, the second in the low nibble. This will be
756 either a 4 bit drive type or 0xf indicating use byte 0x19
757 for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS.
758
759 Needless to say, a non-zero value means we have
760 an AT controller hard disk for that drive.
761
762 Currently the rtc_lock is a bit academic since this
763 driver is non-modular, but someday... ? Paul G.
764 */
765
766 spin_lock_irqsave(&rtc_lock, flags);
767 cmos_disks = CMOS_READ(0x12);
768 spin_unlock_irqrestore(&rtc_lock, flags);
769
770 if (cmos_disks & 0xf0) {
771 if (cmos_disks & 0x0f)
772 NR_HD = 2;
773 else
774 NR_HD = 1;
775 }
776 }
777#endif /* __i386__ */
778#ifdef __arm__
779 if (!NR_HD) {
780 /* We don't know anything about the drive. This means
781 * that you *MUST* specify the drive parameters to the 725 * that you *MUST* specify the drive parameters to the
782 * kernel yourself. 726 * kernel yourself.
727 *
728 * If we were on an i386, we used to read this info from
729 * the BIOS or CMOS. This doesn't work all that well,
730 * since this assumes that this is a primary or secondary
731 * drive, and if we're using this legacy driver, it's
732 * probably an auxilliary controller added to recover
733 * legacy data off an ST-506 drive. Either way, it's
734 * definitely safest to have the user explicitly specify
735 * the information.
783 */ 736 */
784 printk("hd: no drives specified - use hd=cyl,head,sectors" 737 printk("hd: no drives specified - use hd=cyl,head,sectors"
785 " on kernel command line\n"); 738 " on kernel command line\n");
786 }
787#endif
788 if (!NR_HD)
789 goto out; 739 goto out;
740 }
790 741
791 for (drive=0 ; drive < NR_HD ; drive++) { 742 for (drive=0 ; drive < NR_HD ; drive++) {
792 struct gendisk *disk = alloc_disk(64); 743 struct gendisk *disk = alloc_disk(64);