arch/mips/kernel/relocate_kernel.S

   1 /*
   2  * relocate_kernel.S for kexec
   3  * Created by <nschichan@corp.free.fr> on Thu Oct 12 17:49:57 2006
   4  *
   5  * This source code is licensed under the GNU General Public License,
   6  * Version 2.  See the file COPYING for more details.
   7  */
   8
   9 #include <asm/asm.h>
  10 #include <asm/asmmacro.h>
  11 #include <asm/regdef.h>
  12 #include <asm/page.h>
  13 #include <asm/mipsregs.h>
  14 #include <asm/stackframe.h>
  15 #include <asm/addrspace.h>
  16
  17 LEAF(relocate_new_kernel)
  18         PTR_L           s0, kexec_indirection_page
  19         PTR_L           s1, kexec_start_address
  20
  21 process_entry:
  22         PTR_L           s2, (s0)
  23         PTR_ADD         s0, s0, SZREG
  24
  25         /* destination page */
  26         and             s3, s2, 0x1
  27         beq             s3, zero, 1f
  28         and             s4, s2, ~0x1    /* store destination addr in s4 */
  29         move            a0, s4
  30         b               process_entry
  31
  32 1:
  33         /* indirection page, update s0  */
  34         and             s3, s2, 0x2
  35         beq             s3, zero, 1f
  36         and             s0, s2, ~0x2
  37         b               process_entry
  38
  39 1:
  40         /* done page */
  41         and             s3, s2, 0x4
  42         beq             s3, zero, 1f
  43         b               done
  44 1:
  45         /* source page */
  46         and             s3, s2, 0x8
  47         beq             s3, zero, process_entry
  48         and             s2, s2, ~0x8
  49         li              s6, (1 << PAGE_SHIFT) / SZREG
  50
  51 copy_word:
  52         /* copy page word by word */
  53         REG_L           s5, (s2)
  54         REG_S           s5, (s4)
  55         PTR_ADD         s4, s4, SZREG
  56         PTR_ADD         s2, s2, SZREG
  57         LONG_SUB        s6, s6, 1
  58         beq             s6, zero, process_entry
  59         b               copy_word
  60         b               process_entry
  61
  62 done:
  63         /* jump to kexec_start_address */
  64         j               s1
  65         END(relocate_new_kernel)
  66
  67 kexec_start_address:
  68         EXPORT(kexec_start_address)
  69         PTR             0x0
  70         .size           kexec_start_address, PTRSIZE
  71
  72 kexec_indirection_page:
  73         EXPORT(kexec_indirection_page)
  74         PTR             0
  75         .size           kexec_indirection_page, PTRSIZE
  76
  77 relocate_new_kernel_end:
  78
  79 relocate_new_kernel_size:
  80         EXPORT(relocate_new_kernel_size)
  81         PTR             relocate_new_kernel_end - relocate_new_kernel
  82         .size           relocate_new_kernel_size, PTRSIZE