96290cc4eb3c49de81c4c19456db70c2c41dc89d
[linux-2.6.git] / arch / s390 / kernel / relocate_kernel64.S
1 /*
2  * arch/s390/kernel/relocate_kernel64.S
3  *
4  * (C) Copyright IBM Corp. 2005
5  *
6  * Author(s): Rolf Adelsberger <adelsberger@de.ibm.com>
7  *
8  */
9
10 /*
11  * moves the new kernel to its destination...
12  * %r2 = pointer to first kimage_entry_t
13  * %r3 = start address - where to jump to after the job is done...
14  *
15  * %r5 will be used as temp. storage
16  * %r6 holds the destination address
17  * %r7 = PAGE_SIZE
18  * %r8 holds the source address
19  * %r9 = PAGE_SIZE
20  *
21  * 0xf000 is a page_mask
22  */
23
24         .text
25         .globl          relocate_kernel
26         relocate_kernel:
27                 basr    %r13,0          #base address
28         .base:
29                 spx     zero64-.base(%r13)      #absolute addressing mode
30                 stnsm   sys_msk-.base(%r13),0xf8        #disable DAT and IRQ (external)
31         .top:
32                 lghi    %r7,4096        #load PAGE_SIZE in r7
33                 lghi    %r9,4096        #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       .top            #...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       .top            #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      .top            #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       .top
59         .done:
60                 sgr     %r0,%r0         #clear register r0
61                 la      %r4,load_psw-.base(%r13)        #load psw-address into the register
62                 o       %r3,4(%r4)      #or load address into psw
63                 st      %r3,4(%r4)
64                 mvc     0(8,%r0),0(%r4) #copy psw to absolute address 0
65                 sam31                   #31 bit mode
66                 sr      %r1,%r1         #erase register r1
67                 sr      %r2,%r2         #erase register r2
68                 sigp    %r1,%r2,0x12    #set cpuid to zero
69                 lpsw    0               #hopefully start new kernel...
70
71                 .align  8
72         zero64:
73                 .quad   0
74         load_psw:
75                 .long   0x00080000,0x80000000
76         sys_msk:
77                 .quad   0
78         relocate_kernel_end:
79         .globl  relocate_kernel_len
80         relocate_kernel_len:
81                 .quad   relocate_kernel_end - relocate_kernel
82