GNU Linux-libre 4.9.288-gnu1
[releases.git] / arch / s390 / kernel / relocate_kernel.S
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
27 ENTRY(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