arch/arm/kernel/relocate_kernel.S

   1 /*
   2  * relocate_kernel.S - put the kernel image in place to boot
   3  */
   4
   5 #include <linux/linkage.h>
   6 #include <asm/assembler.h>
   7 #include <asm/kexec.h>
   8
   9         .align  3       /* not needed for this code, but keeps fncpy() happy */
  10
  11 ENTRY(relocate_new_kernel)
  12
  13         ldr     r0,kexec_indirection_page
  14         ldr     r1,kexec_start_address
  15
  16         /*
  17          * If there is no indirection page (we are doing crashdumps)
  18          * skip any relocation.
  19          */
  20         cmp     r0, #0
  21         beq     2f
  22
  23 0:      /* top, read another word for the indirection page */
  24         ldr     r3, [r0],#4
  25
  26         /* Is it a destination page. Put destination address to r4 */
  27         tst     r3,#1,0
  28         beq     1f
  29         bic     r4,r3,#1
  30         b       0b
  31 1:
  32         /* Is it an indirection page */
  33         tst     r3,#2,0
  34         beq     1f
  35         bic     r0,r3,#2
  36         b       0b
  37 1:
  38
  39         /* are we done ? */
  40         tst     r3,#4,0
  41         beq     1f
  42         b       2f
  43
  44 1:
  45         /* is it source ? */
  46         tst     r3,#8,0
  47         beq     0b
  48         bic r3,r3,#8
  49         mov r6,#1024
  50 9:
  51         ldr r5,[r3],#4
  52         str r5,[r4],#4
  53         subs r6,r6,#1
  54         bne 9b
  55         b 0b
  56
  57 2:
  58         /* Jump to relocated kernel */
  59         mov lr,r1
  60         mov r0,#0
  61         ldr r1,kexec_mach_type
  62         ldr r2,kexec_boot_atags
  63  ARM(   ret lr  )
  64  THUMB( bx lr           )
  65
  66         .align
  67
  68         .globl kexec_start_address
  69 kexec_start_address:
  70         .long   0x0
  71
  72         .globl kexec_indirection_page
  73 kexec_indirection_page:
  74         .long   0x0
  75
  76         .globl kexec_mach_type
  77 kexec_mach_type:
  78         .long   0x0
  79
  80         /* phy addr of the atags for the new kernel */
  81         .globl kexec_boot_atags
  82 kexec_boot_atags:
  83         .long   0x0
  84
  85 ENDPROC(relocate_new_kernel)
  86
  87 relocate_new_kernel_end:
  88
  89         .globl relocate_new_kernel_size
  90 relocate_new_kernel_size:
  91         .long relocate_new_kernel_end - relocate_new_kernel
  92
  93