Difference between revisions of "Boot-args (iBoot variable)"

From The iPhone Wiki
Jump to: navigation, search
m (one line (serial))
m (rd/rootdev confusion; I don't backlight-level is a boot-arg, only an env variable)
 
(2 intermediate revisions by 2 users not shown)
Line 1: Line 1:
This variable is ignored in firmware >=2.0 when booting to NAND. See also [[Talk:Restore Mode]] These can be booted with a patched iBoot, redsn0w does this when you set custom bootargs.
+
These are boot arguments that the iOS [[kernel]] accepts. These can be booted with a patched [[iBoot]]; untethered [[BootROM]] jailbreaks such as [[redsn0w]] and [[checkra1n]] do this when you set custom boot-args.
   
=Known Settings=
+
= Known Boot Arguments =
  +
{| class="wikitable"
* "rd=md0 nand-enable-reformat=1 -progress" (Used in restore (and update?) ramdisks)
 
  +
|-
* pmd= (used in the [[Ramdisk Hack]])
 
  +
! boot-arg
* 1 (?)
 
  +
! Values
* "-v" ([[Verbose boot]])
 
  +
! Description
* auto-boot (true/false. False does not try to boot the kernelcache)
 
  +
! Notes
* backlight-level (value from 1 to 128 for backlight level)
 
  +
|-
* debug=# (# can be replaced with 0x09 for kernel debugging)
 
  +
| debug=#
* serial=3 (same as [[Debug-uarts (iBoot variable)]])
 
  +
| <code>0x09</code>: Kernel debugging
  +
| Set kernel debug options
  +
|
  +
|-
  +
| nand-enable-reformat=#
  +
| <code>0</code>, <code>1</code>
  +
| Set whether or not to reformat [[NAND]] when restoring
  +
| Used when [[Restore Process|restoring]]
  +
|-
  +
| pmd=#.#
  +
| Start/end address of ramdisk
  +
| Specify a [[Ramdisk|ramdisk]] in memory to boot from
  +
| Used in the [[Ramdisk Hack]]
  +
|-
  +
| -progress
  +
| {{n/a}}
  +
| Enable progress bar when restoring
  +
| Used when [[Restore Process|restoring]]
  +
|-
  +
| rd=?
  +
| <code>'md#'</code>
  +
| Specify the root device to boot from
  +
| Used when [[Restore Process|restoring]]; same as <code>rootdev</code>
  +
|-
  +
| rootdev=?
  +
| <code>'md#'</code>
  +
| Specify the root device to boot from
  +
| Same as <code>rd</code>
  +
|-
  +
| serial=#
  +
| <code>3</code>: Debug output over serial
  +
| Set serial debug options
  +
| Same as <code>[[Debug-uarts (iBoot variable)|debug-uarts]]</code>
  +
|-
  +
| -v
  +
| {{n/a}}
  +
| Enable verbose booting
  +
|
  +
|-
  +
|}
  +
  +
= See Also =
  +
* [[Talk:Restore Mode]]

Latest revision as of 21:15, 9 June 2020

These are boot arguments that the iOS kernel accepts. These can be booted with a patched iBoot; untethered BootROM jailbreaks such as redsn0w and checkra1n do this when you set custom boot-args.

Known Boot Arguments

boot-arg Values Description Notes
debug=# 0x09: Kernel debugging Set kernel debug options
nand-enable-reformat=# 0, 1 Set whether or not to reformat NAND when restoring Used when restoring
pmd=#.# Start/end address of ramdisk Specify a ramdisk in memory to boot from Used in the Ramdisk Hack
-progress N/A Enable progress bar when restoring Used when restoring
rd=? 'md#' Specify the root device to boot from Used when restoring; same as rootdev
rootdev=? 'md#' Specify the root device to boot from Same as rd
serial=# 3: Debug output over serial Set serial debug options Same as debug-uarts
-v N/A Enable verbose booting

See Also