1/* 2 * arch/s390/kernel/relocate_kernel.S 3 * 4 * (C) Copyright IBM Corp. 2005 5 * 6 * Author(s): Rolf Adelsberger, 7 * Heiko Carstens <heiko.carstens@de.ibm.com> 8 * 9 */ 10 11#include <linux/linkage.h> 12 13/* 14 * moves the new kernel to its destination... 15 * %r2 = pointer to first kimage_entry_t 16 * %r3 = start address - where to jump to after the job is done... 17 * 18 * %r5 will be used as temp. storage 19 * %r6 holds the destination address 20 * %r7 = PAGE_SIZE 21 * %r8 holds the source address 22 * %r9 = PAGE_SIZE 23 * %r10 is a page mask 24 */ 25 26 .text 27ENTRY(relocate_kernel) 28 basr %r13,0 # base address 29 .base: 30 stnsm sys_msk-.base(%r13),0xfb # disable DAT 31 stctl %c0,%c15,ctlregs-.base(%r13) 32 stm %r0,%r15,gprregs-.base(%r13) 33 la %r1,load_psw-.base(%r13) 34 mvc 0(8,%r0),0(%r1) 35 la %r0,.back-.base(%r13) 36 st %r0,4(%r0) 37 oi 4(%r0),0x80 38 mvc 0x68(8,%r0),0(%r1) 39 la %r0,.back_pgm-.base(%r13) 40 st %r0,0x6c(%r0) 41 oi 0x6c(%r0),0x80 42 lhi %r0,0 43 diag %r0,%r0,0x308 44 .back: 45 basr %r13,0 46 .back_base: 47 oi have_diag308-.back_base(%r13),0x01 48 lctl %c0,%c15,ctlregs-.back_base(%r13) 49 lm %r0,%r15,gprregs-.back_base(%r13) 50 j .start_reloc 51 .back_pgm: 52 lm %r0,%r15,gprregs-.base(%r13) 53 .start_reloc: 54 lhi %r10,-1 # preparing the mask 55 sll %r10,12 # shift it such that it becomes 0xf000 56 .top: 57 lhi %r7,4096 # load PAGE_SIZE in r7 58 lhi %r9,4096 # load PAGE_SIZE in r9 59 l %r5,0(%r2) # read another word for indirection page 60 ahi %r2,4 # increment pointer 61 tml %r5,0x1 # is it a destination page? 62 je .indir_check # NO, goto "indir_check" 63 lr %r6,%r5 # r6 = r5 64 nr %r6,%r10 # mask it out and... 65 j .top # ...next iteration 66 .indir_check: 67 tml %r5,0x2 # is it a indirection page? 68 je .done_test # NO, goto "done_test" 69 nr %r5,%r10 # YES, mask out, 70 lr %r2,%r5 # move it into the right register, 71 j .top # and read next... 72 .done_test: 73 tml %r5,0x4 # is it the done indicator? 74 je .source_test # NO! Well, then it should be the source indicator... 75 j .done # ok, lets finish it here... 76 .source_test: 77 tml %r5,0x8 # it should be a source indicator... 78 je .top # NO, ignore it... 79 lr %r8,%r5 # r8 = r5 80 nr %r8,%r10 # masking 81 0: mvcle %r6,%r8,0x0 # copy PAGE_SIZE bytes from r8 to r6 - pad with 0 82 jo 0b 83 j .top 84 .done: 85 sr %r0,%r0 # clear register r0 86 la %r4,load_psw-.base(%r13) # load psw-address into the register 87 o %r3,4(%r4) # or load address into psw 88 st %r3,4(%r4) 89 mvc 0(8,%r0),0(%r4) # copy psw to absolute address 0 90 tm have_diag308-.base(%r13),0x01 91 jno .no_diag308 92 diag %r0,%r0,0x308 93 .no_diag308: 94 sr %r1,%r1 # clear %r1 95 sr %r2,%r2 # clear %r2 96 sigp %r1,%r2,0x12 # set cpuid to zero 97 lpsw 0 # hopefully start new kernel... 98 99 .align 8 100 load_psw: 101 .long 0x00080000,0x80000000 102 sys_msk: 103 .quad 0 104 ctlregs: 105 .rept 16 106 .long 0 107 .endr 108 gprregs: 109 .rept 16 110 .long 0 111 .endr 112 have_diag308: 113 .byte 0 114 .align 8 115 relocate_kernel_end: 116 .align 8 117 .globl relocate_kernel_len 118 relocate_kernel_len: 119 .quad relocate_kernel_end - relocate_kernel 120