ide: add "cdrom=" and "chs=" parameters (4706a7e0) · Commits · git / linux-net

Documentation/ide/ide.txt

+14 −17

Original line number	Diff line number	Diff line
		@@ -82,17 +82,16 @@ Drives are normally found by auto-probing and/or examining the CMOS/BIOS data.
		For really weird situations, the apparent (fdisk) geometry can also be specified
		on the kernel "command line" using LILO. The format of such lines is:

		hdx=cyls,heads,sects
		or hdx=cdrom
		ide_core.chs=[interface_number.device_number]:cyls,heads,sects
		or ide_core.cdrom=[interface_number.device_number]

		where hdx can be any of hda through hdh, Three values are required
		(cyls,heads,sects). For example:
		For example:

		hdc=1050,32,64 hdd=cdrom
		ide_core.chs=1.0:1050,32,64 ide_core.cdrom=1.1

		either {hda,hdb} or {hdc,hdd}. The results of successful auto-probing may
		override the physical geometry/irq specified, though the "original" geometry
		may be retained as the "logical" geometry for partitioning purposes (fdisk).
		The results of successful auto-probing may override the physical geometry/irq
		specified, though the "original" geometry may be retained as the "logical"
		geometry for partitioning purposes (fdisk).

		If the auto-probing during boot time confuses a drive (ie. the drive works
		with hd.c but not with ide.c), then an command line option may be specified
		@@ -101,7 +100,7 @@ probe/identification sequence. For example:

		ide_core.noprobe=0.1
		or
		hdc=768,16,32
		ide_core.chs=1.0:768,16,32
		ide_core.noprobe=1.0

		Note that when only one IDE device is attached to an interface, it should be
		@@ -118,9 +117,9 @@ If for some reason your cdrom drive is not found at boot time, you can force
		the probe to look harder by supplying a kernel command line parameter
		via LILO, such as:

		hdc=cdrom /* hdc = "master" on second interface */
		ide_core.cdrom=1.0 /* "master" on second interface (hdc) */
		or
		hdd=cdrom /* hdd = "slave" on second interface */
		ide_core.cdrom=1.1 /* "slave" on second interface (hdd) */

		For example, a GW2000 system might have a hard drive on the primary
		interface (/dev/hda) and an IDE cdrom drive on the secondary interface
		@@ -182,12 +181,6 @@ driver using the "options=" keyword to insmod, while replacing any ',' with
		Summary of ide driver parameters for kernel command line
		--------------------------------------------------------

		"hdx=" is recognized for all "x" from "a" to "u", such as "hdc".

		"hdx=cdrom" : drive is present, and is a cdrom drive

		"hdx=cyl,head,sect" : disk drive is present, with specified geometry

		"ide=doubler" : probe/support IDE doublers on Amiga

		There may be more options than shown -- use the source, Luke!
		@@ -230,6 +223,10 @@ Other kernel parameters for ide_core are:

		* "nowerr=[interface_number.device_number]" to ignore the WRERR_STAT bit

		* "cdrom=[interface_number.device_number]" to force device as a CD-ROM

		* "chs=[interface_number.device_number]" to force device as a disk (using CHS)

		================================================================================

		Some Terminology

drivers/ide/ide.c

+66 −5

Original line number	Diff line number	Diff line
		@@ -924,7 +924,7 @@ static int __init ide_setup(char *s)
		drive->media = ide_cdrom;
		/* an ATAPI device ignores DRDY */
		drive->ready_stat = 0;
		goto done;
		goto obsolete_option;
		case -5: /* nodma */
		drive->nodma = 1;
		goto obsolete_option;
		@@ -948,7 +948,7 @@ static int __init ide_setup(char *s)
		drive->sect = drive->bios_sect = vals[2];
		drive->present = 1;
		drive->forced_geom = 1;
		goto done;
		goto obsolete_option;
		default:
		goto bad_option;
		}
		@@ -975,9 +975,6 @@ static int __init ide_setup(char *s)
		obsolete_option:
		printk(" -- OBSOLETE OPTION, WILL BE REMOVED SOON!\n");
		return 1;
		done:
		printk("\n");
		return 1;
		}

		EXPORT_SYMBOL(ide_lock);
		@@ -1167,6 +1164,51 @@ static unsigned int ide_nowerr;
		module_param_call(nowerr, ide_set_dev_param_mask, NULL, &ide_nowerr, 0);
		MODULE_PARM_DESC(nowerr, "ignore the WRERR_STAT bit for a device");

		static unsigned int ide_cdroms;

		module_param_call(cdrom, ide_set_dev_param_mask, NULL, &ide_cdroms, 0);
		MODULE_PARM_DESC(cdrom, "force device as a CD-ROM");

		struct chs_geom {
		unsigned int cyl;
		u8 head;
		u8 sect;
		};

		static unsigned int ide_disks;
		static struct chs_geom ide_disks_chs[MAX_HWIFS * MAX_DRIVES];

		static int ide_set_disk_chs(const char str, struct kernel_param kp)
		{
		int a, b, c = 0, h = 0, s = 0, i, j = 1;

		if (sscanf(str, "%d.%d:%d,%d,%d", &a, &b, &c, &h, &s) != 5 &&
		sscanf(str, "%d.%d:%d", &a, &b, &j) != 3)
		return -EINVAL;

		i = a * MAX_DRIVES + b;

		if (i >= MAX_HWIFS * MAX_DRIVES \|\| j < 0 \|\| j > 1)
		return -EINVAL;

		if (c > INT_MAX \|\| h > 255 \|\| s > 255)
		return -EINVAL;

		if (j)
		ide_disks \|= (1 << i);
		else
		ide_disks &= (1 << i);

		ide_disks_chs[i].cyl = c;
		ide_disks_chs[i].head = h;
		ide_disks_chs[i].sect = s;

		return 0;
		}

		module_param_call(chs, ide_set_disk_chs, NULL, NULL, 0);
		MODULE_PARM_DESC(chs, "force device as a disk (using CHS)");

		static void ide_dev_apply_params(ide_drive_t *drive)
		{
		int i = drive->hwif->index * MAX_DRIVES + drive->select.b.unit;
		@@ -1189,6 +1231,25 @@ static void ide_dev_apply_params(ide_drive_t *drive)
		drive->name);
		drive->bad_wstat = BAD_R_STAT;
		}
		if (ide_cdroms & (1 << i)) {
		printk(KERN_INFO "ide: forcing %s as a CD-ROM\n", drive->name);
		drive->present = 1;
		drive->media = ide_cdrom;
		/* an ATAPI device ignores DRDY */
		drive->ready_stat = 0;
		}
		if (ide_disks & (1 << i)) {
		drive->cyl = drive->bios_cyl = ide_disks_chs[i].cyl;
		drive->head = drive->bios_head = ide_disks_chs[i].head;
		drive->sect = drive->bios_sect = ide_disks_chs[i].sect;
		drive->forced_geom = 1;
		printk(KERN_INFO "ide: forcing %s as a disk (%d/%d/%d)\n",
		drive->name,
		drive->cyl, drive->head, drive->sect);
		drive->present = 1;
		drive->media = ide_disk;
		drive->ready_stat = READY_STAT;
		}
		}

		static unsigned int ide_ignore_cable;