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#include <asm/sigp.h> 13 14/* 15 * moves the new kernel to its destination... 16 * %r2 = pointer to first kimage_entry_t 17 * %r3 = start address - where to jump to after the job is done... 18 * 19 * %r5 will be used as temp. storage 20 * %r6 holds the destination address 21 * %r7 = PAGE_SIZE 22 * %r8 holds the source address 23 * %r9 = PAGE_SIZE 24 * %r10 is a page mask 25 */ 26 27 .text 28ENTRY(relocate_kernel) 29 basr %r13,0 # base address 30 .base: 31 stnsm sys_msk-.base(%r13),0xfb # disable DAT 32 stctl %c0,%c15,ctlregs-.base(%r13) 33 stm %r0,%r15,gprregs-.base(%r13) 34 la %r1,load_psw-.base(%r13) 35 mvc 0(8,%r0),0(%r1) 36 la %r0,.back-.base(%r13) 37 st %r0,4(%r0) 38 oi 4(%r0),0x80 39 mvc 0x68(8,%r0),0(%r1) 40 la %r0,.back_pgm-.base(%r13) 41 st %r0,0x6c(%r0) 42 oi 0x6c(%r0),0x80 43 lhi %r0,0 44 diag %r0,%r0,0x308 45 .back: 46 basr %r13,0 47 .back_base: 48 oi have_diag308-.back_base(%r13),0x01 49 lctl %c0,%c15,ctlregs-.back_base(%r13) 50 lm %r0,%r15,gprregs-.back_base(%r13) 51 j .start_reloc 52 .back_pgm: 53 lm %r0,%r15,gprregs-.base(%r13) 54 .start_reloc: 55 lhi %r10,-1 # preparing the mask 56 sll %r10,12 # shift it such that it becomes 0xf000 57 .top: 58 lhi %r7,4096 # load PAGE_SIZE in r7 59 lhi %r9,4096 # load PAGE_SIZE in r9 60 l %r5,0(%r2) # read another word for indirection page 61 ahi %r2,4 # increment pointer 62 tml %r5,0x1 # is it a destination page? 63 je .indir_check # NO, goto "indir_check" 64 lr %r6,%r5 # r6 = r5 65 nr %r6,%r10 # mask it out and... 66 j .top # ...next iteration 67 .indir_check: 68 tml %r5,0x2 # is it a indirection page? 69 je .done_test # NO, goto "done_test" 70 nr %r5,%r10 # YES, mask out, 71 lr %r2,%r5 # move it into the right register, 72 j .top # and read next... 73 .done_test: 74 tml %r5,0x4 # is it the done indicator? 75 je .source_test # NO! Well, then it should be the source indicator... 76 j .done # ok, lets finish it here... 77 .source_test: 78 tml %r5,0x8 # it should be a source indicator... 79 je .top # NO, ignore it... 80 lr %r8,%r5 # r8 = r5 81 nr %r8,%r10 # masking 82 0: mvcle %r6,%r8,0x0 # copy PAGE_SIZE bytes from r8 to r6 - pad with 0 83 jo 0b 84 j .top 85 .done: 86 sr %r0,%r0 # clear register r0 87 la %r4,load_psw-.base(%r13) # load psw-address into the register 88 o %r3,4(%r4) # or load address into psw 89 st %r3,4(%r4) 90 mvc 0(8,%r0),0(%r4) # copy psw to absolute address 0 91 tm have_diag308-.base(%r13),0x01 92 jno .no_diag308 93 diag %r0,%r0,0x308 94 .no_diag308: 95 sr %r1,%r1 # clear %r1 96 sr %r2,%r2 # clear %r2 97 sigp %r1,%r2,SIGP_SET_ARCHITECTURE # set cpuid to zero 98 lpsw 0 # hopefully start new kernel... 99 100 .align 8 101 load_psw: 102 .long 0x00080000,0x80000000 103 sys_msk: 104 .quad 0 105 ctlregs: 106 .rept 16 107 .long 0 108 .endr 109 gprregs: 110 .rept 16 111 .long 0 112 .endr 113 have_diag308: 114 .byte 0 115 .align 8 116 relocate_kernel_end: 117 .align 8 118 .globl relocate_kernel_len 119 relocate_kernel_len: 120 .quad relocate_kernel_end - relocate_kernel 121