kernel_samsung_a34x-permissive/arch/s390/kernel/relocate_kernel.S
2024-04-28 15:51:13 +02:00

75 lines
2 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright IBM Corp. 2005
*
* Author(s): Rolf Adelsberger,
* Heiko Carstens <heiko.carstens@de.ibm.com>
*
*/
#include <linux/linkage.h>
#include <asm/page.h>
#include <asm/sigp.h>
/*
* moves the new kernel to its destination...
* %r2 = pointer to first kimage_entry_t
* %r3 = start address - where to jump to after the job is done...
*
* %r5 will be used as temp. storage
* %r6 holds the destination address
* %r7 = PAGE_SIZE
* %r8 holds the source address
* %r9 = PAGE_SIZE
*
* 0xf000 is a page_mask
*/
.text
ENTRY(relocate_kernel)
basr %r13,0 # base address
.base:
lghi %r7,PAGE_SIZE # load PAGE_SIZE in r7
lghi %r9,PAGE_SIZE # load PAGE_SIZE in r9
lg %r5,0(%r2) # read another word for indirection page
aghi %r2,8 # increment pointer
tml %r5,0x1 # is it a destination page?
je .indir_check # NO, goto "indir_check"
lgr %r6,%r5 # r6 = r5
nill %r6,0xf000 # mask it out and...
j .base # ...next iteration
.indir_check:
tml %r5,0x2 # is it a indirection page?
je .done_test # NO, goto "done_test"
nill %r5,0xf000 # YES, mask out,
lgr %r2,%r5 # move it into the right register,
j .base # and read next...
.done_test:
tml %r5,0x4 # is it the done indicator?
je .source_test # NO! Well, then it should be the source indicator...
j .done # ok, lets finish it here...
.source_test:
tml %r5,0x8 # it should be a source indicator...
je .base # NO, ignore it...
lgr %r8,%r5 # r8 = r5
nill %r8,0xf000 # masking
0: mvcle %r6,%r8,0x0 # copy PAGE_SIZE bytes from r8 to r6 - pad with 0
jo 0b
j .base
.done:
sgr %r0,%r0 # clear register r0
la %r4,load_psw-.base(%r13) # load psw-address into the register
o %r3,4(%r4) # or load address into psw
st %r3,4(%r4)
mvc 0(8,%r0),0(%r4) # copy psw to absolute address 0
diag %r0,%r0,0x308
.align 8
load_psw:
.long 0x00080000,0x80000000
relocate_kernel_end:
.align 8
.globl relocate_kernel_len
relocate_kernel_len:
.quad relocate_kernel_end - relocate_kernel