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