| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/sh/boot/compressed/head.S |
| 3 | * |
| 4 | * Copyright (C) 1999 Stuart Menefy |
| 5 | * Copyright (C) 2003 SUGIOKA Toshinobu |
| 6 | */ |
| 7 | |
| 8 | .text |
| 9 | |
| 10 | #include <linux/config.h> |
| 11 | #include <linux/linkage.h> |
| 12 | |
| 13 | .global startup |
| 14 | startup: |
| 15 | /* Load initial status register */ |
| 16 | mov.l init_sr, r1 |
| 17 | ldc r1, sr |
| 18 | |
| 19 | /* Move myself to proper location if necessary */ |
| 20 | mova 1f, r0 |
| 21 | mov.l 1f, r2 |
| 22 | cmp/eq r2, r0 |
| 23 | bt clear_bss |
| 24 | sub r0, r2 |
| 25 | mov.l bss_start_addr, r0 |
| 26 | mov #0xe0, r1 |
| 27 | and r1, r0 ! align cache line |
| 28 | mov.l text_start_addr, r3 |
| 29 | mov r0, r1 |
| 30 | sub r2, r1 |
| 31 | 3: |
| 32 | mov.l @r1, r4 |
| 33 | mov.l @(4,r1), r5 |
| 34 | mov.l @(8,r1), r6 |
| 35 | mov.l @(12,r1), r7 |
| 36 | mov.l @(16,r1), r8 |
| 37 | mov.l @(20,r1), r9 |
| 38 | mov.l @(24,r1), r10 |
| 39 | mov.l @(28,r1), r11 |
| 40 | mov.l r4, @r0 |
| 41 | mov.l r5, @(4,r0) |
| 42 | mov.l r6, @(8,r0) |
| 43 | mov.l r7, @(12,r0) |
| 44 | mov.l r8, @(16,r0) |
| 45 | mov.l r9, @(20,r0) |
| 46 | mov.l r10, @(24,r0) |
| 47 | mov.l r11, @(28,r0) |
| 48 | #ifdef CONFIG_CPU_SH4 |
| 49 | ocbwb @r0 |
| 50 | #endif |
| 51 | cmp/hi r3, r0 |
| 52 | add #-32, r0 |
| 53 | bt/s 3b |
| 54 | add #-32, r1 |
| 55 | mov.l 2f, r0 |
| 56 | jmp @r0 |
| 57 | nop |
| 58 | |
| 59 | .align 2 |
| 60 | 1: .long 1b |
| 61 | 2: .long clear_bss |
| 62 | text_start_addr: |
| 63 | .long startup |
| 64 | |
| 65 | /* Clear BSS */ |
| 66 | clear_bss: |
| 67 | mov.l end_addr, r1 |
| 68 | mov.l bss_start_addr, r2 |
| 69 | mov #0, r0 |
| 70 | l1: |
| 71 | mov.l r0, @-r1 |
| 72 | cmp/eq r1,r2 |
| 73 | bf l1 |
| 74 | |
| 75 | /* Set the initial pointer. */ |
| 76 | mov.l init_stack_addr, r0 |
| 77 | mov.l @r0, r15 |
| 78 | |
| 79 | /* Decompress the kernel */ |
| 80 | mov.l decompress_kernel_addr, r0 |
| 81 | jsr @r0 |
| 82 | nop |
| 83 | |
| 84 | /* Jump to the start of the decompressed kernel */ |
| 85 | mov.l kernel_start_addr, r0 |
| 86 | jmp @r0 |
| 87 | nop |
| 88 | |
| 89 | .align 2 |
| 90 | bss_start_addr: |
| 91 | .long __bss_start |
| 92 | end_addr: |
| 93 | .long _end |
| 94 | init_sr: |
| 95 | .long 0x400000F0 /* Privileged mode, Bank=0, Block=0, IMASK=0xF */ |
| 96 | init_stack_addr: |
| 97 | .long stack_start |
| 98 | decompress_kernel_addr: |
| 99 | .long decompress_kernel |
| 100 | kernel_start_addr: |
| 101 | .long _text+0x1000 |
| 102 | |
| 103 | .align 9 |
| 104 | fake_headers_as_bzImage: |
| 105 | .word 0 |
| 106 | .ascii "HdrS" ! header signature |
| 107 | .word 0x0202 ! header version number (>= 0x0105) |
| 108 | ! or else old loadlin-1.5 will fail) |
| 109 | .word 0 ! default_switch |
| 110 | .word 0 ! SETUPSEG |
| 111 | .word 0x1000 |
| 112 | .word 0 ! pointing to kernel version string |
| 113 | .byte 0 ! = 0, old one (LILO, Loadlin, |
| 114 | ! 0xTV: T=0 for LILO |
| 115 | ! V = version |
| 116 | .byte 1 ! Load flags bzImage=1 |
| 117 | .word 0x8000 ! size to move, when setup is not |
| 118 | .long 0x100000 ! 0x100000 = default for big kernel |
| 119 | .long 0 ! address of loaded ramdisk image |
| 120 | .long 0 # its size in bytes |