1/*
2 * Copyright IBM Corp. 2005
3 *
4 * Author(s): Rolf Adelsberger,
5 *	      Heiko Carstens <heiko.carstens@de.ibm.com>
6 *
7 */
8
9#include <linux/linkage.h>
10#include <asm/sigp.h>
11
12/*
13 * moves the new kernel to its destination...
14 * %r2 = pointer to first kimage_entry_t
15 * %r3 = start address - where to jump to after the job is done...
16 *
17 * %r5 will be used as temp. storage
18 * %r6 holds the destination address
19 * %r7 = PAGE_SIZE
20 * %r8 holds the source address
21 * %r9 = PAGE_SIZE
22 *
23 * 0xf000 is a page_mask
24 */
25
26	.text
27ENTRY(relocate_kernel)
28		basr	%r13,0		# base address
29	.base:
30		stnsm	sys_msk-.base(%r13),0xfb	# disable DAT
31		stctg	%c0,%c15,ctlregs-.base(%r13)
32		stmg	%r0,%r15,gprregs-.base(%r13)
33		lghi	%r0,3
34		sllg	%r0,%r0,31
35		stg	%r0,0x1d0(%r0)
36		la	%r0,.back_pgm-.base(%r13)
37		stg	%r0,0x1d8(%r0)
38		la	%r1,load_psw-.base(%r13)
39		mvc	0(8,%r0),0(%r1)
40		la	%r0,.back-.base(%r13)
41		st	%r0,4(%r0)
42		oi	4(%r0),0x80
43		lghi	%r0,0
44		diag	%r0,%r0,0x308
45	.back:
46		lhi	%r1,1		# mode 1 = esame
47		sigp	%r1,%r0,SIGP_SET_ARCHITECTURE # switch to esame mode
48		sam64			# switch to 64 bit addressing mode
49		basr	%r13,0
50	.back_base:
51		oi	have_diag308-.back_base(%r13),0x01
52		lctlg	%c0,%c15,ctlregs-.back_base(%r13)
53		lmg	%r0,%r15,gprregs-.back_base(%r13)
54		j	.top
55	.back_pgm:
56		lmg	%r0,%r15,gprregs-.base(%r13)
57	.top:
58		lghi	%r7,4096	# load PAGE_SIZE in r7
59		lghi	%r9,4096	# load PAGE_SIZE in r9
60		lg	%r5,0(%r2)	# read another word for indirection page
61		aghi	%r2,8		# increment pointer
62		tml	%r5,0x1		# is it a destination page?
63		je	.indir_check	# NO, goto "indir_check"
64		lgr	%r6,%r5		# r6 = r5
65		nill	%r6,0xf000	# 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		nill	%r5,0xf000	# YES, mask out,
71		lgr	%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		lgr	%r8,%r5		# r8 = r5
81		nill	%r8,0xf000	# 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		sgr	%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		sam31			# 31 bit mode
96		sr	%r1,%r1		# erase register r1
97		sr	%r2,%r2		# erase register r2
98		sigp	%r1,%r2,SIGP_SET_ARCHITECTURE # set cpuid to zero
99		lpsw	0		# hopefully start new kernel...
100
101		.align	8
102	load_psw:
103		.long	0x00080000,0x80000000
104	sys_msk:
105		.quad	0
106	ctlregs:
107		.rept	16
108		.quad	0
109		.endr
110	gprregs:
111		.rept	16
112		.quad	0
113		.endr
114	have_diag308:
115		.byte	0
116		.align	8
117	relocate_kernel_end:
118	.align 8
119	.globl	relocate_kernel_len
120	relocate_kernel_len:
121		.quad	relocate_kernel_end - relocate_kernel
122