Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes...
[linux-2.6] / arch / s390 / kernel / relocate_kernel.S
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