1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright IBM Corp. 2005
4 *
5 * Author(s): Rolf Adelsberger,
6 *	      Heiko Carstens <heiko.carstens@de.ibm.com>
7 *
8 */
9
10#include <linux/linkage.h>
11#include <asm/page.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 *
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		sgr	%r0,%r0		# clear register r0
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
79