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
for each drive for which you'd like the drive to skip the hardware
probe/identification sequence. For example:
- hdb=noprobe
+ ide_core.noprobe=0.1
or
- hdc=768,16,32
- hdc=noprobe
+ 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
jumpered as "single" or "master", *not* "slave". Many folks have had
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
When ide.c is used as a module, you can pass command line parameters to the
driver using the "options=" keyword to insmod, while replacing any ',' with
-';'. For example:
-
- insmod ide.o options="hda=nodma hdb=nodma"
+';'.
================================================================================
Summary of ide driver parameters for kernel command line
--------------------------------------------------------
- "hdx=" is recognized for all "x" from "a" to "u", such as "hdc".
-
- "idex=" is recognized for all "x" from "0" to "9", such as "ide1".
-
- "hdx=noprobe" : drive may be present, but do not probe for it
-
- "hdx=none" : drive is NOT present, ignore cmos and do not probe
-
- "hdx=nowerr" : ignore the WRERR_STAT bit on this drive
-
- "hdx=cdrom" : drive is present, and is a cdrom drive
+For legacy IDE VLB host drivers (ali14xx/dtc2278/ht6560b/qd65xx/umc8672)
+you need to explicitly enable probing by using "probe" kernel parameter,
+i.e. to enable probing for ALI M14xx chipsets (ali14xx host driver) use:
- "hdx=cyl,head,sect" : disk drive is present, with specified geometry
+* "ali14xx.probe" boot option when ali14xx driver is built-in the kernel
- "hdx=autotune" : driver will attempt to tune interface speed
- to the fastest PIO mode supported,
- if possible for this drive only.
- Not fully supported by all chipset types,
- and quite likely to cause trouble with
- older/odd IDE drives.
+* "probe" module parameter when ali14xx driver is compiled as module
+ ("modprobe ali14xx probe")
- "hdx=nodma" : disallow DMA
+Also for legacy CMD640 host driver (cmd640) you need to use "probe_vlb"
+kernel paremeter to enable probing for VLB version of the chipset (PCI ones
+are detected automatically).
- "idebus=xx" : inform IDE driver of VESA/PCI bus speed in MHz,
- where "xx" is between 20 and 66 inclusive,
- used when tuning chipset PIO modes.
- For PCI bus, 25 is correct for a P75 system,
- 30 is correct for P90,P120,P180 systems,
- and 33 is used for P100,P133,P166 systems.
- If in doubt, use idebus=33 for PCI.
- As for VLB, it is safest to not specify it.
- Bigger values are safer than smaller ones.
+You also need to use "probe" kernel parameter for ide-4drives driver
+(support for IDE generic chipset with four drives on one port).
- "idex=serialize" : do not overlap operations on idex. Please note
- that you will have to specify this option for
- both the respective primary and secondary channel
- to take effect.
+To enable support for IDE doublers on Amiga use "doubler" kernel parameter
+for gayle host driver (i.e. "gayle.doubler" if the driver is built-in).
- "idex=four" : four drives on idex and ide(x^1) share same ports
+To force ignoring cable detection (this should be needed only if you're using
+short 40-wires cable which cannot be automatically detected - if this is not
+a case please report it as a bug instead) use "ignore_cable" kernel parameter:
- "idex=reset" : reset interface after probe
+* "ide_core.ignore_cable=[interface_number]" boot option if IDE is built-in
+ (i.e. "ide_core.ignore_cable=1" to force ignoring cable for "ide1")
- "idex=ata66" : informs the interface that it has an 80c cable
- for chipsets that are ATA-66 capable, but the
- ability to bit test for detection is currently
- unknown.
+* "ignore_cable=[interface_number]" module parameter (for ide_core module)
+ if IDE is compiled as module
- "ide=doubler" : probe/support IDE doublers on Amiga
+Other kernel parameters for ide_core are:
-There may be more options than shown -- use the source, Luke!
+* "nodma=[interface_number.device_number]" to disallow DMA for a device
-Everything else is rejected with a "BAD OPTION" message.
+* "noflush=[interface_number.device_number]" to disable flush requests
-For legacy IDE VLB host drivers (ali14xx/dtc2278/ht6560b/qd65xx/umc8672)
-you need to explicitly enable probing by using "probe" kernel parameter,
-i.e. to enable probing for ALI M14xx chipsets (ali14xx host driver) use:
+* "noprobe=[interface_number.device_number]" to skip probing
-* "ali14xx.probe" boot option when ali14xx driver is built-in the kernel
+* "nowerr=[interface_number.device_number]" to ignore the WRERR_STAT bit
-* "probe" module parameter when ali14xx driver is compiled as module
- ("modprobe ali14xx probe")
+* "cdrom=[interface_number.device_number]" to force device as a CD-ROM
-Also for legacy CMD640 host driver (cmd640) you need to use "probe_vlb"
-kernel paremeter to enable probing for VLB version of the chipset (PCI ones
-are detected automatically).
+* "chs=[interface_number.device_number]" to force device as a disk (using CHS)
================================================================================
projects / linux-2.6-omap-h63xx.git / blobdiff