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
11LC_EXT_NEW_PSW		= 0x58			# addr of ext int handler
12LC_EXT_NEW_PSW_64	= 0x1b0			# addr of ext int handler 64 bit
13LC_EXT_INT_PARAM	= 0x80			# addr of ext int parameter
14LC_EXT_INT_CODE		= 0x86			# addr of ext int code
15LC_AR_MODE_ID		= 0xa3
16
17#
18# Subroutine which waits synchronously until either an external interruption
19# or a timeout occurs.
20#
21# Parameters:
22#   R2	= 0 for no timeout, non-zero for timeout in (approximated) seconds
23#
24# Returns:
25#   R2	= 0 on interrupt, 2 on timeout
26#   R3	= external interruption parameter if R2=0
27#
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	la	%r9,.LextpswS1-.LbaseS1(%r13)
36#ifdef CONFIG_64BIT
37	tm	LC_AR_MODE_ID,1
38	jno	.Lesa1
39	la	%r8,LC_EXT_NEW_PSW_64		# register int handler 64 bit
40	la	%r9,.LextpswS1_64-.LbaseS1(%r13)
41.Lesa1:
42#endif
43	mvc	.LoldpswS1-.LbaseS1(16,%r13),0(%r8)
44	mvc	0(16,%r8),0(%r9)
45	lhi	%r6,0x0200			# cr mask for ext int (cr0.54)
46	ltr	%r2,%r2
47	jz	.LsetctS1
48	ahi	%r6,0x0800			# cr mask for clock int (cr0.52)
49	stck	.LtimeS1-.LbaseS1(%r13)		# initiate timeout
50	al	%r2,.LtimeS1-.LbaseS1(%r13)
51	st	%r2,.LtimeS1-.LbaseS1(%r13)
52	sckc	.LtimeS1-.LbaseS1(%r13)
53
54.LsetctS1:
55	stctl	%c0,%c0,.LctlS1-.LbaseS1(%r13)	# enable required interrupts
56	l	%r0,.LctlS1-.LbaseS1(%r13)
57	lhi	%r1,~(0x200 | 0x800)		# clear old values
58	nr	%r1,%r0
59	or	%r1,%r6				# set new value
60	st	%r1,.LctlS1-.LbaseS1(%r13)
61	lctl	%c0,%c0,.LctlS1-.LbaseS1(%r13)
62	st	%r0,.LctlS1-.LbaseS1(%r13)
63	lhi	%r2,2				# return code for timeout
64.LloopS1:
65	lpsw	.LwaitpswS1-.LbaseS1(%r13)	# wait until interrupt
66.LwaitS1:
67	lh	%r7,LC_EXT_INT_CODE
68	chi	%r7,0x1004			# timeout?
69	je	.LtimeoutS1
70	chi	%r7,0x2401			# service int?
71	jne	.LloopS1
72	sr	%r2,%r2
73	l	%r3,LC_EXT_INT_PARAM
74.LtimeoutS1:
75	lctl	%c0,%c0,.LctlS1-.LbaseS1(%r13)	# restore interrupt setting
76	# restore old handler
77	mvc	0(16,%r8),.LoldpswS1-.LbaseS1(%r13)
78	lm	%r6,%r15,120(%r15)		# restore registers
79	br	%r14				# return to caller
80
81	.align	8
82.LoldpswS1:
83	.long	0, 0, 0, 0			# old ext int PSW
84.LextpswS1:
85	.long	0x00080000, 0x80000000+.LwaitS1	# PSW to handle ext int
86#ifdef CONFIG_64BIT
87.LextpswS1_64:
88	.quad	0x0000000180000000, .LwaitS1	# PSW to handle ext int, 64 bit
89#endif
90.LwaitpswS1:
91	.long	0x010a0000, 0x00000000+.LloopS1	# PSW to wait for ext int
92.LtimeS1:
93	.quad	0				# current time
94.LctlS1:
95	.long	0				# CT0 contents
96
97#
98# Subroutine to synchronously issue a service call.
99#
100# Parameters:
101#   R2	= command word
102#   R3	= sccb address
103#
104# Returns:
105#   R2	= 0 on success, 1 on failure
106#   R3	= sccb response code if R2 = 0
107#
108
109_sclp_servc:
110	stm	%r6,%r15,24(%r15)		# save registers
111	ahi	%r15,-96			# create stack frame
112	lr	%r6,%r2				# save command word
113	lr	%r7,%r3				# save sccb address
114.LretryS2:
115	lhi	%r2,1				# error return code
116	.insn	rre,0xb2200000,%r6,%r7		# servc
117	brc	1,.LendS2			# exit if not operational
118	brc	8,.LnotbusyS2			# go on if not busy
119	sr	%r2,%r2				# wait until no longer busy
120	bras	%r14,_sclp_wait_int
121	j	.LretryS2			# retry
122.LnotbusyS2:
123	sr	%r2,%r2				# wait until result
124	bras	%r14,_sclp_wait_int
125	sr	%r2,%r2
126	lh	%r3,6(%r7)
127.LendS2:
128	lm	%r6,%r15,120(%r15)		# restore registers
129	br	%r14
130
131#
132# Subroutine to set up the SCLP interface.
133#
134# Parameters:
135#   R2	= 0 to activate, non-zero to deactivate
136#
137# Returns:
138#   R2	= 0 on success, non-zero on failure
139#
140
141_sclp_setup:
142	stm	%r6,%r15,24(%r15)		# save registers
143	ahi	%r15,-96			# create stack frame
144	basr	%r13,0				# get base register
145.LbaseS3:
146	l	%r6,.LsccbS0-.LbaseS3(%r13)	# prepare init mask sccb
147	mvc	0(.LinitendS3-.LinitsccbS3,%r6),.LinitsccbS3-.LbaseS3(%r13)
148	ltr	%r2,%r2				# initialization?
149	jz	.LdoinitS3			# go ahead
150	# clear masks
151	xc	.LinitmaskS3-.LinitsccbS3(8,%r6),.LinitmaskS3-.LinitsccbS3(%r6)
152.LdoinitS3:
153	l	%r2,.LwritemaskS3-.LbaseS3(%r13)# get command word
154	lr	%r3,%r6				# get sccb address
155	bras	%r14,_sclp_servc		# issue service call
156	ltr	%r2,%r2				# servc successful?
157	jnz	.LerrorS3
158	chi	%r3,0x20			# write mask successful?
159	jne	.LerrorS3
160	# check masks
161	la	%r2,.LinitmaskS3-.LinitsccbS3(%r6)
162	l	%r1,0(%r2)			# receive mask ok?
163	n	%r1,12(%r2)
164	cl	%r1,0(%r2)
165	jne	.LerrorS3
166	l	%r1,4(%r2)			# send mask ok?
167	n	%r1,8(%r2)
168	cl	%r1,4(%r2)
169	sr	%r2,%r2
170	je	.LendS3
171.LerrorS3:
172	lhi	%r2,1				# error return code
173.LendS3:
174	lm	%r6,%r15,120(%r15)		# restore registers
175	br	%r14
176.LwritemaskS3:
177	.long	0x00780005			# SCLP command for write mask
178.LinitsccbS3:
179	.word	.LinitendS3-.LinitsccbS3
180	.byte	0,0,0,0
181	.word	0
182	.word	0
183	.word	4
184.LinitmaskS3:
185	.long	0x80000000
186	.long	0x40000000
187	.long	0
188	.long	0
189.LinitendS3:
190
191#
192# Subroutine which prints a given text to the SCLP console.
193#
194# Parameters:
195#   R2	= address of nil-terminated ASCII text
196#
197# Returns:
198#   R2	= 0 on success, 1 on failure
199#
200
201_sclp_print:
202	stm	%r6,%r15,24(%r15)		# save registers
203	ahi	%r15,-96			# create stack frame
204	basr	%r13,0				# get base register
205.LbaseS4:
206	l	%r8,.LsccbS0-.LbaseS4(%r13)	# prepare write data sccb
207	mvc	0(.LmtoS4-.LwritesccbS4,%r8),.LwritesccbS4-.LbaseS4(%r13)
208	la	%r7,.LmtoS4-.LwritesccbS4(%r8)	# current mto addr
209	sr	%r0,%r0
210	l	%r10,.Lascebc-.LbaseS4(%r13)	# address of translation table
211.LinitmtoS4:
212	# initialize mto
213	mvc	0(.LmtoendS4-.LmtoS4,%r7),.LmtoS4-.LbaseS4(%r13)
214	lhi	%r6,.LmtoendS4-.LmtoS4		# current mto length
215.LloopS4:
216	ic	%r0,0(%r2)			# get character
217	ahi	%r2,1
218	ltr	%r0,%r0				# end of string?
219	jz	.LfinalizemtoS4
220	chi	%r0,0x15			# end of line (NL)?
221	jz	.LfinalizemtoS4
222	stc	%r0,0(%r6,%r7)			# copy to mto
223	la	%r11,0(%r6,%r7)
224	tr	0(1,%r11),0(%r10)		# translate to EBCDIC
225	ahi	%r6,1
226	j	.LloopS4
227.LfinalizemtoS4:
228	sth	%r6,0(%r7)			# update mto length
229	lh	%r9,.LmdbS4-.LwritesccbS4(%r8)	# update mdb length
230	ar	%r9,%r6
231	sth	%r9,.LmdbS4-.LwritesccbS4(%r8)
232	lh	%r9,.LevbufS4-.LwritesccbS4(%r8)# update evbuf length
233	ar	%r9,%r6
234	sth	%r9,.LevbufS4-.LwritesccbS4(%r8)
235	lh	%r9,0(%r8)			# update sccb length
236	ar	%r9,%r6
237	sth	%r9,0(%r8)
238	ar	%r7,%r6				# update current mto address
239	ltr	%r0,%r0				# more characters?
240	jnz	.LinitmtoS4
241	l	%r2,.LwritedataS4-.LbaseS4(%r13)# write data
242	lr	%r3,%r8
243	bras	%r14,_sclp_servc
244	ltr	%r2,%r2				# servc successful?
245	jnz	.LendS4
246	chi	%r3,0x20			# write data successful?
247	je	.LendS4
248	lhi	%r2,1				# error return code
249.LendS4:
250	lm	%r6,%r15,120(%r15)		# restore registers
251	br	%r14
252
253#
254# Function which prints a given text to the SCLP console.
255#
256# Parameters:
257#   R2	= address of nil-terminated ASCII text
258#
259# Returns:
260#   R2	= 0 on success, 1 on failure
261#
262
263	.globl _sclp_print_early
264_sclp_print_early:
265	stm	%r6,%r15,24(%r15)		# save registers
266	ahi	%r15,-96			# create stack frame
267#ifdef CONFIG_64BIT
268	tm	LC_AR_MODE_ID,1
269	jno	.Lesa2
270	ahi	%r15,-80
271	stmh	%r6,%r15,96(%r15)		# store upper register halves
272.Lesa2:
273#endif
274	lr	%r10,%r2			# save string pointer
275	lhi	%r2,0
276	bras	%r14,_sclp_setup		# enable console
277	ltr	%r2,%r2
278	jnz	.LendS5
279	lr	%r2,%r10
280	bras	%r14,_sclp_print		# print string
281	ltr	%r2,%r2
282	jnz	.LendS5
283	lhi	%r2,1
284	bras	%r14,_sclp_setup		# disable console
285.LendS5:
286#ifdef CONFIG_64BIT
287	tm	LC_AR_MODE_ID,1
288	jno	.Lesa3
289	lmh	%r6,%r15,96(%r15)		# store upper register halves
290	ahi	%r15,80
291.Lesa3:
292#endif
293	lm	%r6,%r15,120(%r15)		# restore registers
294	br	%r14
295
296.LwritedataS4:
297	.long	0x00760005			# SCLP command for write data
298.LwritesccbS4:
299	# sccb
300	.word	.LmtoS4-.LwritesccbS4
301	.byte	0
302	.byte	0,0,0
303	.word	0
304
305	# evbuf
306.LevbufS4:
307	.word	.LmtoS4-.LevbufS4
308	.byte	0x02
309	.byte	0
310	.word	0
311
312.LmdbS4:
313	# mdb
314	.word	.LmtoS4-.LmdbS4
315	.word	1
316	.long	0xd4c4c240
317	.long	1
318
319	# go
320.LgoS4:
321	.word	.LmtoS4-.LgoS4
322	.word	1
323	.long	0
324	.byte	0,0,0,0,0,0,0,0
325	.byte	0,0,0
326	.byte	0
327	.byte	0,0,0,0,0,0,0
328	.byte	0
329	.word	0
330	.byte	0,0,0,0,0,0,0,0,0,0
331	.byte	0,0,0,0,0,0,0,0
332	.byte	0,0,0,0,0,0,0,0
333
334.LmtoS4:
335	.word	.LmtoendS4-.LmtoS4
336	.word	4
337	.word	0x1000
338	.byte	0
339	.byte	0,0,0
340.LmtoendS4:
341
342	# Global constants
343.LsccbS0:
344	.long	_sclp_work_area
345.Lascebc:
346	.long	_ascebc
347
348.section .data,"aw",@progbits
349	.balign 4096
350_sclp_work_area:
351	.fill	4096
352.previous
353