relocate_kernel.S (2059B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * Copyright IBM Corp. 2005 4 * 5 * Author(s): Rolf Adelsberger 6 * 7 */ 8 9#include <linux/linkage.h> 10#include <asm/page.h> 11#include <asm/sigp.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 * %r4 = subcode 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 * 25 * 0xf000 is a page_mask 26 */ 27 28 .text 29ENTRY(relocate_kernel) 30 basr %r13,0 # base address 31 .base: 32 lghi %r7,PAGE_SIZE # load PAGE_SIZE in r7 33 lghi %r9,PAGE_SIZE # load PAGE_SIZE in r9 34 lg %r5,0(%r2) # read another word for indirection page 35 aghi %r2,8 # increment pointer 36 tml %r5,0x1 # is it a destination page? 37 je .indir_check # NO, goto "indir_check" 38 lgr %r6,%r5 # r6 = r5 39 nill %r6,0xf000 # mask it out and... 40 j .base # ...next iteration 41 .indir_check: 42 tml %r5,0x2 # is it a indirection page? 43 je .done_test # NO, goto "done_test" 44 nill %r5,0xf000 # YES, mask out, 45 lgr %r2,%r5 # move it into the right register, 46 j .base # and read next... 47 .done_test: 48 tml %r5,0x4 # is it the done indicator? 49 je .source_test # NO! Well, then it should be the source indicator... 50 j .done # ok, lets finish it here... 51 .source_test: 52 tml %r5,0x8 # it should be a source indicator... 53 je .base # NO, ignore it... 54 lgr %r8,%r5 # r8 = r5 55 nill %r8,0xf000 # masking 56 0: mvcle %r6,%r8,0x0 # copy PAGE_SIZE bytes from r8 to r6 - pad with 0 57 jo 0b 58 j .base 59 .done: 60 lgr %r0,%r4 # subcode 61 cghi %r3,0 62 je .diag 63 la %r4,load_psw-.base(%r13) # load psw-address into the register 64 o %r3,4(%r4) # or load address into psw 65 st %r3,4(%r4) 66 mvc 0(8,%r0),0(%r4) # copy psw to absolute address 0 67 .diag: 68 diag %r0,%r0,0x308 69ENDPROC(relocate_kernel) 70 71 .align 8 72 load_psw: 73 .long 0x00080000,0x80000000 74 relocate_kernel_end: 75 .align 8 76 .globl relocate_kernel_len 77 relocate_kernel_len: 78 .quad relocate_kernel_end - relocate_kernel