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Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7278295f94d..9a5b6658c65 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -950,6 +950,41 @@ and is between 256 and 4096 characters. It is defined in the file when set. Format: <int> + libata.force= [LIBATA] Force configurations. The format is comma + separated list of "[ID:]VAL" where ID is + PORT[:DEVICE]. PORT and DEVICE are decimal numbers + matching port, link or device. Basically, it matches + the ATA ID string printed on console by libata. If + the whole ID part is omitted, the last PORT and DEVICE + values are used. If ID hasn't been specified yet, the + configuration applies to all ports, links and devices. + + If only DEVICE is omitted, the parameter applies to + the port and all links and devices behind it. DEVICE + number of 0 either selects the first device or the + first fan-out link behind PMP device. It does not + select the host link. DEVICE number of 15 selects the + host link and device attached to it. + + The VAL specifies the configuration to force. As long + as there's no ambiguity shortcut notation is allowed. + For example, both 1.5 and 1.5G would work for 1.5Gbps. + The following configurations can be forced. + + * Cable type: 40c, 80c, short40c, unk, ign or sata. + Any ID with matching PORT is used. + + * SATA link speed limit: 1.5Gbps or 3.0Gbps. + + * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7]. + udma[/][16,25,33,44,66,100,133] notation is also + allowed. + + * [no]ncq: Turn on or off NCQ. + + If there are multiple matching configurations changing + the same attribute, the last one is used. + load_ramdisk= [RAM] List of ramdisks to load from floppy See Documentation/ramdisk.txt. |