Merge branch 'timers-for-linus-ntp' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6] / arch / s390 / kernel / sclp.S
1 /*
2  * Mini SCLP driver.
3  *
4  * Copyright IBM Corp. 2004,2009
5  *
6  *   Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com>,
7  *              Heiko Carstens <heiko.carstens@de.ibm.com>,
8  *
9  */
10
11 LC_EXT_NEW_PSW          = 0x58                  # addr of ext int handler
12 LC_EXT_INT_PARAM        = 0x80                  # addr of ext int parameter
13 LC_EXT_INT_CODE         = 0x86                  # addr of ext int code
14
15 #
16 # Subroutine which waits synchronously until either an external interruption
17 # or a timeout occurs.
18 #
19 # Parameters:
20 #   R2  = 0 for no timeout, non-zero for timeout in (approximated) seconds
21 #
22 # Returns:
23 #   R2  = 0 on interrupt, 2 on timeout
24 #   R3  = external interruption parameter if R2=0
25 #
26
27 .section ".init.text","ax"
28
29 _sclp_wait_int:
30         stm     %r6,%r15,24(%r15)               # save registers
31         basr    %r13,0                          # get base register
32 .LbaseS1:
33         ahi     %r15,-96                        # create stack frame
34         la      %r8,LC_EXT_NEW_PSW              # register int handler
35         mvc     .LoldpswS1-.LbaseS1(8,%r13),0(%r8)
36         mvc     0(8,%r8),.LextpswS1-.LbaseS1(%r13)
37         lhi     %r6,0x0200                      # cr mask for ext int (cr0.54)
38         ltr     %r2,%r2
39         jz      .LsetctS1
40         ahi     %r6,0x0800                      # cr mask for clock int (cr0.52)
41         stck    .LtimeS1-.LbaseS1(%r13)         # initiate timeout
42         al      %r2,.LtimeS1-.LbaseS1(%r13)
43         st      %r2,.LtimeS1-.LbaseS1(%r13)
44         sckc    .LtimeS1-.LbaseS1(%r13)
45
46 .LsetctS1:
47         stctl   %c0,%c0,.LctlS1-.LbaseS1(%r13)  # enable required interrupts
48         l       %r0,.LctlS1-.LbaseS1(%r13)
49         lhi     %r1,~(0x200 | 0x800)            # clear old values
50         nr      %r1,%r0
51         or      %r1,%r6                         # set new value
52         st      %r1,.LctlS1-.LbaseS1(%r13)
53         lctl    %c0,%c0,.LctlS1-.LbaseS1(%r13)
54         st      %r0,.LctlS1-.LbaseS1(%r13)
55         lhi     %r2,2                           # return code for timeout
56 .LloopS1:
57         lpsw    .LwaitpswS1-.LbaseS1(%r13)      # wait until interrupt
58 .LwaitS1:
59         lh      %r7,LC_EXT_INT_CODE
60         chi     %r7,0x1004                      # timeout?
61         je      .LtimeoutS1
62         chi     %r7,0x2401                      # service int?
63         jne     .LloopS1
64         sr      %r2,%r2
65         l       %r3,LC_EXT_INT_PARAM
66 .LtimeoutS1:
67         lctl    %c0,%c0,.LctlS1-.LbaseS1(%r13)  # restore interrupt setting
68         # restore old handler
69         mvc     0(8,%r8),.LoldpswS1-.LbaseS1(%r13)
70         lm      %r6,%r15,120(%r15)              # restore registers
71         br      %r14                            # return to caller
72
73         .align  8
74 .LoldpswS1:
75         .long   0, 0                            # old ext int PSW
76 .LextpswS1:
77         .long   0x00080000, 0x80000000+.LwaitS1 # PSW to handle ext int
78 .LwaitpswS1:
79         .long   0x010a0000, 0x00000000+.LloopS1 # PSW to wait for ext int
80 .LtimeS1:
81         .quad   0                               # current time
82 .LctlS1:
83         .long   0                               # CT0 contents
84
85 #
86 # Subroutine to synchronously issue a service call.
87 #
88 # Parameters:
89 #   R2  = command word
90 #   R3  = sccb address
91 #
92 # Returns:
93 #   R2  = 0 on success, 1 on failure
94 #   R3  = sccb response code if R2 = 0
95 #
96
97 _sclp_servc:
98         stm     %r6,%r15,24(%r15)               # save registers
99         ahi     %r15,-96                        # create stack frame
100         lr      %r6,%r2                         # save command word
101         lr      %r7,%r3                         # save sccb address
102 .LretryS2:
103         lhi     %r2,1                           # error return code
104         .insn   rre,0xb2200000,%r6,%r7          # servc
105         brc     1,.LendS2                       # exit if not operational
106         brc     8,.LnotbusyS2                   # go on if not busy
107         sr      %r2,%r2                         # wait until no longer busy
108         bras    %r14,_sclp_wait_int
109         j       .LretryS2                       # retry
110 .LnotbusyS2:
111         sr      %r2,%r2                         # wait until result
112         bras    %r14,_sclp_wait_int
113         sr      %r2,%r2
114         lh      %r3,6(%r7)
115 .LendS2:
116         lm      %r6,%r15,120(%r15)              # restore registers
117         br      %r14
118
119 #
120 # Subroutine to set up the SCLP interface.
121 #
122 # Parameters:
123 #   R2  = 0 to activate, non-zero to deactivate
124 #
125 # Returns:
126 #   R2  = 0 on success, non-zero on failure
127 #
128
129 _sclp_setup:
130         stm     %r6,%r15,24(%r15)               # save registers
131         ahi     %r15,-96                        # create stack frame
132         basr    %r13,0                          # get base register
133 .LbaseS3:
134         l       %r6,.LsccbS0-.LbaseS3(%r13)     # prepare init mask sccb
135         mvc     0(.LinitendS3-.LinitsccbS3,%r6),.LinitsccbS3-.LbaseS3(%r13)
136         ltr     %r2,%r2                         # initialization?
137         jz      .LdoinitS3                      # go ahead
138         # clear masks
139         xc      .LinitmaskS3-.LinitsccbS3(8,%r6),.LinitmaskS3-.LinitsccbS3(%r6)
140 .LdoinitS3:
141         l       %r2,.LwritemaskS3-.LbaseS3(%r13)# get command word
142         lr      %r3,%r6                         # get sccb address
143         bras    %r14,_sclp_servc                # issue service call
144         ltr     %r2,%r2                         # servc successful?
145         jnz     .LerrorS3
146         chi     %r3,0x20                        # write mask successful?
147         jne     .LerrorS3
148         # check masks
149         la      %r2,.LinitmaskS3-.LinitsccbS3(%r6)
150         l       %r1,0(%r2)                      # receive mask ok?
151         n       %r1,12(%r2)
152         cl      %r1,0(%r2)
153         jne     .LerrorS3
154         l       %r1,4(%r2)                      # send mask ok?
155         n       %r1,8(%r2)
156         cl      %r1,4(%r2)
157         sr      %r2,%r2
158         je      .LendS3
159 .LerrorS3:
160         lhi     %r2,1                           # error return code
161 .LendS3:
162         lm      %r6,%r15,120(%r15)              # restore registers
163         br      %r14
164 .LwritemaskS3:
165         .long   0x00780005                      # SCLP command for write mask
166 .LinitsccbS3:
167         .word   .LinitendS3-.LinitsccbS3
168         .byte   0,0,0,0
169         .word   0
170         .word   0
171         .word   4
172 .LinitmaskS3:
173         .long   0x80000000
174         .long   0x40000000
175         .long   0
176         .long   0
177 .LinitendS3:
178
179 #
180 # Subroutine which prints a given text to the SCLP console.
181 #
182 # Parameters:
183 #   R2  = address of nil-terminated ASCII text
184 #
185 # Returns:
186 #   R2  = 0 on success, 1 on failure
187 #
188
189 _sclp_print:
190         stm     %r6,%r15,24(%r15)               # save registers
191         ahi     %r15,-96                        # create stack frame
192         basr    %r13,0                          # get base register
193 .LbaseS4:
194         l       %r8,.LsccbS0-.LbaseS4(%r13)     # prepare write data sccb
195         mvc     0(.LmtoS4-.LwritesccbS4,%r8),.LwritesccbS4-.LbaseS4(%r13)
196         la      %r7,.LmtoS4-.LwritesccbS4(%r8)  # current mto addr
197         sr      %r0,%r0
198         l       %r10,.Lascebc-.LbaseS4(%r13)    # address of translation table
199 .LinitmtoS4:
200         # initialize mto
201         mvc     0(.LmtoendS4-.LmtoS4,%r7),.LmtoS4-.LbaseS4(%r13)
202         lhi     %r6,.LmtoendS4-.LmtoS4          # current mto length
203 .LloopS4:
204         ic      %r0,0(%r2)                      # get character
205         ahi     %r2,1
206         ltr     %r0,%r0                         # end of string?
207         jz      .LfinalizemtoS4
208         chi     %r0,0x15                        # end of line (NL)?
209         jz      .LfinalizemtoS4
210         stc     %r0,0(%r6,%r7)                  # copy to mto
211         la      %r11,0(%r6,%r7)
212         tr      0(1,%r11),0(%r10)               # translate to EBCDIC
213         ahi     %r6,1
214         j       .LloopS4
215 .LfinalizemtoS4:
216         sth     %r6,0(%r7)                      # update mto length
217         lh      %r9,.LmdbS4-.LwritesccbS4(%r8)  # update mdb length
218         ar      %r9,%r6
219         sth     %r9,.LmdbS4-.LwritesccbS4(%r8)
220         lh      %r9,.LevbufS4-.LwritesccbS4(%r8)# update evbuf length
221         ar      %r9,%r6
222         sth     %r9,.LevbufS4-.LwritesccbS4(%r8)
223         lh      %r9,0(%r8)                      # update sccb length
224         ar      %r9,%r6
225         sth     %r9,0(%r8)
226         ar      %r7,%r6                         # update current mto adress
227         ltr     %r0,%r0                         # more characters?
228         jnz     .LinitmtoS4
229         l       %r2,.LwritedataS4-.LbaseS4(%r13)# write data
230         lr      %r3,%r8
231         bras    %r14,_sclp_servc
232         ltr     %r2,%r2                         # servc successful?
233         jnz     .LendS4
234         chi     %r3,0x20                        # write data successful?
235         je      .LendS4
236         lhi     %r2,1                           # error return code
237 .LendS4:
238         lm      %r6,%r15,120(%r15)              # restore registers
239         br      %r14
240
241 #
242 # Function which prints a given text to the SCLP console.
243 #
244 # Parameters:
245 #   R2  = address of nil-terminated ASCII text
246 #
247 # Returns:
248 #   R2  = 0 on success, 1 on failure
249 #
250
251         .globl _sclp_print_early
252 _sclp_print_early:
253         stm     %r6,%r15,24(%r15)               # save registers
254         ahi     %r15,-96                        # create stack frame
255         lr      %r10,%r2                        # save string pointer
256         lhi     %r2,0
257         bras    %r14,_sclp_setup                # enable console
258         ltr     %r2,%r2
259         jnz     .LendS5
260         lr      %r2,%r10
261         bras    %r14,_sclp_print                # print string
262         ltr     %r2,%r2
263         jnz     .LendS5
264         lhi     %r2,1
265         bras    %r14,_sclp_setup                # disable console
266 .LendS5:
267         lm      %r6,%r15,120(%r15)              # restore registers
268         br      %r14
269
270 .LwritedataS4:
271         .long   0x00760005                      # SCLP command for write data
272 .LwritesccbS4:
273         # sccb
274         .word   .LmtoS4-.LwritesccbS4
275         .byte   0
276         .byte   0,0,0
277         .word   0
278
279         # evbuf
280 .LevbufS4:
281         .word   .LmtoS4-.LevbufS4
282         .byte   0x02
283         .byte   0
284         .word   0
285
286 .LmdbS4:
287         # mdb
288         .word   .LmtoS4-.LmdbS4
289         .word   1
290         .long   0xd4c4c240
291         .long   1
292
293         # go
294 .LgoS4:
295         .word   .LmtoS4-.LgoS4
296         .word   1
297         .long   0
298         .byte   0,0,0,0,0,0,0,0
299         .byte   0,0,0
300         .byte   0
301         .byte   0,0,0,0,0,0,0
302         .byte   0
303         .word   0
304         .byte   0,0,0,0,0,0,0,0,0,0
305         .byte   0,0,0,0,0,0,0,0
306         .byte   0,0,0,0,0,0,0,0
307
308 .LmtoS4:
309         .word   .LmtoendS4-.LmtoS4
310         .word   4
311         .word   0x1000
312         .byte   0
313         .byte   0,0,0
314 .LmtoendS4:
315
316         # Global constants
317 .LsccbS0:
318         .long   _sclp_work_area
319 .Lascebc:
320         .long   _ascebc
321 .previous
322
323 .section ".init.data","a"
324         .balign 4096
325 _sclp_work_area:
326         .fill   4096
327 .previous