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Linus Torvalds1da177e2005-04-16 15:20:36 -07001 Information about the Linux/PPC kernel images
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3
4Please mail me (Cort Dougan, cort@fsmlabs.com) if you have questions,
5comments or corrections.
6
7This document is meant to answer several questions I've had about how
8the PReP system boots and how Linux/PPC interacts with that mechanism.
9It would be nice if we could have information on how other architectures
10boot here as well. If you have anything to contribute, please
11let me know.
12
13
141. PReP boot file
15
16 This is the file necessary to boot PReP systems from floppy or
17 hard drive. The firmware reads the PReP partition table entry
18 and will load the image accordingly.
19
20 To boot the zImage, copy it onto a floppy with dd if=zImage of=/dev/fd0h1440
21 or onto a PReP hard drive partition with dd if=zImage of=/dev/sda4
22 assuming you've created a PReP partition (type 0x41) with fdisk on
23 /dev/sda4.
24
25 The layout of the image format is:
26
27 0x0 +------------+
28 | | PReP partition table entry
29 | |
30 0x400 +------------+
31 | | Bootstrap program code + data
32 | |
33 | |
34 +------------+
35 | | compressed kernel, elf header removed
36 +------------+
37 | | initrd (if loaded)
38 +------------+
39 | | Elf section table for bootstrap program
40 +------------+
41
42
432. MBX boot file
44
45 The MBX boards can load an elf image, and relocate it to the
46 proper location in memory - it copies the image to the location it was
47 linked at.