xref: /openbmc/linux/arch/m68k/ifpsp060/os.S (revision 922a9bd1)
1|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2|MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP
3|M68000 Hi-Performance Microprocessor Division
4|M68060 Software Package
5|Production Release P1.00 -- October 10, 1994
6|
7|M68060 Software Package Copyright © 1993, 1994 Motorola Inc.  All rights reserved.
8|
9|THE SOFTWARE is provided on an "AS IS" basis and without warranty.
10|To the maximum extent permitted by applicable law,
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12|INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
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14|(INCLUDING ANY MODIFIED VERSIONS THEREOF) and any accompanying written materials.
15|
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19|BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR OTHER PECUNIARY LOSS)
20|ARISING OF THE USE OR INABILITY TO USE THE SOFTWARE.
21|Motorola assumes no responsibility for the maintenance and support of the SOFTWARE.
22|
23|You are hereby granted a copyright license to use, modify, and distribute the SOFTWARE
24|so long as this entire notice is retained without alteration in any modified and/or
25|redistributed versions, and that such modified versions are clearly identified as such.
26|No licenses are granted by implication, estoppel or otherwise under any patents
27|or trademarks of Motorola, Inc.
28|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
29| os.s
30|
31| This file contains:
32|	- example "Call-Out"s required by both the ISP and FPSP.
33|
34
35#include <linux/linkage.h>
36
37|################################
38| EXAMPLE CALL-OUTS		#
39|				#
40| _060_dmem_write()		#
41| _060_dmem_read()		#
42| _060_imem_read()		#
43| _060_dmem_read_byte()		#
44| _060_dmem_read_word()		#
45| _060_dmem_read_long()		#
46| _060_imem_read_word()		#
47| _060_imem_read_long()		#
48| _060_dmem_write_byte()	#
49| _060_dmem_write_word()	#
50| _060_dmem_write_long()	#
51|				#
52| _060_real_trace()		#
53| _060_real_access()		#
54|################################
55
56|
57| Each IO routine checks to see if the memory write/read is to/from user
58| or supervisor application space. The examples below use simple "move"
59| instructions for supervisor mode applications and call _copyin()/_copyout()
60| for user mode applications.
61| When installing the 060SP, the _copyin()/_copyout() equivalents for a
62| given operating system should be substituted.
63|
64| The addresses within the 060SP are guaranteed to be on the stack.
65| The result is that Unix processes are allowed to sleep as a consequence
66| of a page fault during a _copyout.
67|
68| Linux/68k: The _060_[id]mem_{read,write}_{byte,word,long} functions
69| (i.e. all the known length <= 4) are implemented by single moves
70| statements instead of (more expensive) copy{in,out} calls, if
71| working in user space
72
73|
74| _060_dmem_write():
75|
76| Writes to data memory while in supervisor mode.
77|
78| INPUTS:
79|	a0 - supervisor source address
80|	a1 - user destination address
81|	d0 - number of bytes to write
82|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
83| OUTPUTS:
84|	d1 - 0 = success, !0 = failure
85|
86	.global		_060_dmem_write
87_060_dmem_write:
88	subq.l		#1,%d0
89	btst		#0x5,0x4(%a6)		| check for supervisor state
90	beqs		user_write
91super_write:
92	move.b		(%a0)+,(%a1)+		| copy 1 byte
93	dbra		%d0,super_write		| quit if --ctr < 0
94	clr.l		%d1			| return success
95	rts
96user_write:
97	move.b		(%a0)+,%d1		| copy 1 byte
98copyoutae:
99	movs.b		%d1,(%a1)+
100	dbra		%d0,user_write		| quit if --ctr < 0
101	clr.l		%d1			| return success
102	rts
103
104|
105| _060_imem_read(), _060_dmem_read():
106|
107| Reads from data/instruction memory while in supervisor mode.
108|
109| INPUTS:
110|	a0 - user source address
111|	a1 - supervisor destination address
112|	d0 - number of bytes to read
113|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
114| OUTPUTS:
115|	d1 - 0 = success, !0 = failure
116|
117	.global		_060_imem_read
118	.global		_060_dmem_read
119_060_imem_read:
120_060_dmem_read:
121	subq.l		#1,%d0
122	btst		#0x5,0x4(%a6)		| check for supervisor state
123	beqs		user_read
124super_read:
125	move.b		(%a0)+,(%a1)+		| copy 1 byte
126	dbra		%d0,super_read		| quit if --ctr < 0
127	clr.l		%d1			| return success
128	rts
129user_read:
130copyinae:
131	movs.b		(%a0)+,%d1
132	move.b		%d1,(%a1)+		| copy 1 byte
133	dbra		%d0,user_read		| quit if --ctr < 0
134	clr.l		%d1			| return success
135	rts
136
137|
138| _060_dmem_read_byte():
139|
140| Read a data byte from user memory.
141|
142| INPUTS:
143|	a0 - user source address
144|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
145| OUTPUTS:
146|	d0 - data byte in d0
147|	d1 - 0 = success, !0 = failure
148|
149	.global		_060_dmem_read_byte
150_060_dmem_read_byte:
151	clr.l		%d0			| clear whole longword
152	clr.l		%d1			| assume success
153	btst		#0x5,0x4(%a6)		| check for supervisor state
154	bnes		dmrbs			| supervisor
155dmrbuae:movs.b		(%a0),%d0		| fetch user byte
156	rts
157dmrbs:	move.b		(%a0),%d0		| fetch super byte
158	rts
159
160|
161| _060_dmem_read_word():
162|
163| Read a data word from user memory.
164|
165| INPUTS:
166|	a0 - user source address
167|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
168| OUTPUTS:
169|	d0 - data word in d0
170|	d1 - 0 = success, !0 = failure
171|
172| _060_imem_read_word():
173|
174| Read an instruction word from user memory.
175|
176| INPUTS:
177|	a0 - user source address
178|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
179| OUTPUTS:
180|	d0 - instruction word in d0
181|	d1 - 0 = success, !0 = failure
182|
183	.global		_060_dmem_read_word
184	.global		_060_imem_read_word
185_060_dmem_read_word:
186_060_imem_read_word:
187	clr.l		%d1			| assume success
188	clr.l		%d0			| clear whole longword
189	btst		#0x5,0x4(%a6)		| check for supervisor state
190	bnes		dmrws			| supervisor
191dmrwuae:movs.w		(%a0), %d0		| fetch user word
192	rts
193dmrws:	move.w		(%a0), %d0		| fetch super word
194	rts
195
196|
197| _060_dmem_read_long():
198|
199
200|
201| INPUTS:
202|	a0 - user source address
203|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
204| OUTPUTS:
205|	d0 - data longword in d0
206|	d1 - 0 = success, !0 = failure
207|
208| _060_imem_read_long():
209|
210| Read an instruction longword from user memory.
211|
212| INPUTS:
213|	a0 - user source address
214|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
215| OUTPUTS:
216|	d0 - instruction longword in d0
217|	d1 - 0 = success, !0 = failure
218|
219	.global		_060_dmem_read_long
220	.global		_060_imem_read_long
221_060_dmem_read_long:
222_060_imem_read_long:
223	clr.l		%d1			| assume success
224	btst		#0x5,0x4(%a6)		| check for supervisor state
225	bnes		dmrls			| supervisor
226dmrluae:movs.l		(%a0),%d0		| fetch user longword
227	rts
228dmrls:	move.l		(%a0),%d0		| fetch super longword
229	rts
230
231|
232| _060_dmem_write_byte():
233|
234| Write a data byte to user memory.
235|
236| INPUTS:
237|	a0 - user destination address
238|	d0 - data byte in d0
239|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
240| OUTPUTS:
241|	d1 - 0 = success, !0 = failure
242|
243	.global		_060_dmem_write_byte
244_060_dmem_write_byte:
245	clr.l		%d1			| assume success
246	btst		#0x5,0x4(%a6)		| check for supervisor state
247	bnes		dmwbs			| supervisor
248dmwbuae:movs.b		%d0,(%a0)		| store user byte
249	rts
250dmwbs:	move.b		%d0,(%a0)		| store super byte
251	rts
252
253|
254| _060_dmem_write_word():
255|
256| Write a data word to user memory.
257|
258| INPUTS:
259|	a0 - user destination address
260|	d0 - data word in d0
261|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
262| OUTPUTS:
263|	d1 - 0 = success, !0 = failure
264|
265	.global		_060_dmem_write_word
266_060_dmem_write_word:
267	clr.l		%d1			| assume success
268	btst		#0x5,0x4(%a6)		| check for supervisor state
269	bnes		dmwws			| supervisor
270dmwwu:
271dmwwuae:movs.w		%d0,(%a0)		| store user word
272	bras		dmwwr
273dmwws:	move.w		%d0,(%a0)		| store super word
274dmwwr:	clr.l		%d1			| return success
275	rts
276
277|
278| _060_dmem_write_long():
279|
280| Write a data longword to user memory.
281|
282| INPUTS:
283|	a0 - user destination address
284|	d0 - data longword in d0
285|	0x4(%a6),bit5 - 1 = supervisor mode, 0 = user mode
286| OUTPUTS:
287|	d1 - 0 = success, !0 = failure
288|
289	.global		_060_dmem_write_long
290_060_dmem_write_long:
291	clr.l		%d1			| assume success
292	btst		#0x5,0x4(%a6)		| check for supervisor state
293	bnes		dmwls			| supervisor
294dmwluae:movs.l		%d0,(%a0)		| store user longword
295	rts
296dmwls:	move.l		%d0,(%a0)		| store super longword
297	rts
298
299
300#if 0
301|###############################################
302
303|
304| Use these routines if your kernel doesn't have _copyout/_copyin equivalents.
305| Assumes that D0/D1/A0/A1 are scratch registers. The _copyin/_copyout
306| below assume that the SFC/DFC have been set previously.
307|
308| Linux/68k: These are basically non-inlined versions of
309| memcpy_{to,from}fs, but without long-transfer optimization
310| Note: Assumed that SFC/DFC are pointing correctly to user data
311| space... Should be right, or are there any exceptions?
312
313|
314| int _copyout(supervisor_addr, user_addr, nbytes)
315|
316	.global		_copyout
317_copyout:
318	move.l		4(%sp),%a0		| source
319	move.l		8(%sp),%a1		| destination
320	move.l		12(%sp),%d0		| count
321	subq.l		#1,%d0
322moreout:
323	move.b		(%a0)+,%d1		| fetch supervisor byte
324copyoutae:
325	movs.b		%d1,(%a1)+		| store user byte
326	dbra		%d0,moreout		| are we through yet?
327	moveq		#0,%d0			| return success
328	rts
329
330|
331| int _copyin(user_addr, supervisor_addr, nbytes)
332|
333	.global		_copyin
334_copyin:
335	move.l		4(%sp),%a0		| source
336	move.l		8(%sp),%a1		| destination
337	move.l		12(%sp),%d0		| count
338    subq.l      #1,%d0
339morein:
340copyinae:
341	movs.b		(%a0)+,%d1		| fetch user byte
342	move.b		%d1,(%a1)+		| write supervisor byte
343	dbra		%d0,morein		| are we through yet?
344	moveq		#0,%d0			| return success
345	rts
346#endif
347
348|###########################################################################
349
350|
351| _060_real_trace():
352|
353| This is the exit point for the 060FPSP when an instruction is being traced
354| and there are no other higher priority exceptions pending for this instruction
355| or they have already been processed.
356|
357| The sample code below simply executes an "rte".
358|
359	.global		_060_real_trace
360_060_real_trace:
361	bral	trap
362
363|
364| _060_real_access():
365|
366| This is the exit point for the 060FPSP when an access error exception
367| is encountered. The routine below should point to the operating system
368| handler for access error exceptions. The exception stack frame is an
369| 8-word access error frame.
370|
371| The sample routine below simply executes an "rte" instruction which
372| is most likely the incorrect thing to do and could put the system
373| into an infinite loop.
374|
375	.global		_060_real_access
376_060_real_access:
377	bral	buserr
378
379
380
381| Execption handling for movs access to illegal memory
382	.section .fixup,"ax"
383	.even
3841:	moveq		#-1,%d1
385	rts
386.section __ex_table,"a"
387	.align 4
388	.long	dmrbuae,1b
389	.long	dmrwuae,1b
390	.long	dmrluae,1b
391	.long	dmwbuae,1b
392	.long	dmwwuae,1b
393	.long	dmwluae,1b
394	.long	copyoutae,1b
395	.long	copyinae,1b
396	.text
397