patch-2.3.16 linux/drivers/block/cmos-probe.c

• Lines: 79
• Date: Thu Aug 26 13:44:03 1999
• Orig file: v2.3.15/linux/drivers/block/cmos-probe.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.15/linux/drivers/block/cmos-probe.c linux/drivers/block/cmos-probe.c
@@ -0,0 +1,78 @@
+/*
+ *  linux/drivers/block/cmos-probe.c	Version 1.00  August 16, 1999
+ *
+ *  Copyright (C) 1994-1999  Linus Torvalds & authors (see below)
+ */
+
+#undef REALLY_SLOW_IO		/* most systems can safely undef this */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/major.h>
+#include <linux/errno.h>
+#include <linux/genhd.h>
+#include <linux/malloc.h>
+#include <linux/delay.h>
+#include <linux/ide.h>
+
+
+#include <asm/byteorder.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+/*
+ * We query CMOS about hard disks : it could be that we have a SCSI/ESDI/etc
+ * controller that is BIOS compatible with ST-506, and thus showing up in our
+ * BIOS table, but not register compatible, and therefore not present in CMOS.
+ *
+ * Furthermore, we will assume that our ST-506 drives <if any> are the primary
+ * drives in the system -- the ones reflected as drive 1 or 2.  The first
+ * drive is stored in the high nibble of CMOS byte 0x12, the second in the low
+ * nibble.  This will be either a 4 bit drive type or 0xf indicating use byte
+ * 0x19 for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS.  A non-zero value
+ * means we have an AT controller hard disk for that drive.
+ *
+ * Of course, there is no guarantee that either drive is actually on the
+ * "primary" IDE interface, but we don't bother trying to sort that out here.
+ * If a drive is not actually on the primary interface, then these parameters
+ * will be ignored.  This results in the user having to supply the logical
+ * drive geometry as a boot parameter for each drive not on the primary i/f.
+ *
+ * The only "perfect" way to handle this would be to modify the setup.[cS] code
+ * to do BIOS calls Int13h/Fn08h and Int13h/Fn48h to get all of the drive info
+ * for us during initialization.  I have the necessary docs -- any takers?  -ml
+ */
+void probe_cmos_for_drives (ide_hwif_t *hwif)
+{
+#ifdef __i386__
+	extern struct drive_info_struct drive_info;
+	byte cmos_disks, *BIOS = (byte *) &drive_info;
+	int unit;
+
+#ifdef CONFIG_BLK_DEV_PDC4030
+	if (hwif->chipset == ide_pdc4030 && hwif->channel != 0)
+		return;
+#endif /* CONFIG_BLK_DEV_PDC4030 */
+	outb_p(0x12,0x70);		/* specify CMOS address 0x12 */
+	cmos_disks = inb_p(0x71);	/* read the data from 0x12 */
+	/* Extract drive geometry from CMOS+BIOS if not already setup */
+	for (unit = 0; unit < MAX_DRIVES; ++unit) {
+		ide_drive_t *drive = &hwif->drives[unit];
+		if ((cmos_disks & (0xf0 >> (unit*4))) && !drive->present && !drive->nobios) {
+			drive->cyl   = drive->bios_cyl  = *(unsigned short *)BIOS;
+			drive->head  = drive->bios_head = *(BIOS+2);
+			drive->sect  = drive->bios_sect = *(BIOS+14);
+			drive->ctl   = *(BIOS+8);
+			drive->present = 1;
+		}
+		BIOS += 16;
+	}
+#endif
+}