xref: /openbmc/linux/arch/m68k/ifpsp060/iskeleton.S (revision 7effbd18)
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,
11|MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED,
12|INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
13|and any warranty against infringement with regard to the SOFTWARE
14|(INCLUDING ANY MODIFIED VERSIONS THEREOF) and any accompanying written materials.
15|
16|To the maximum extent permitted by applicable law,
17|IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER
18|(INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS,
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| iskeleton.s
30|
31| This file contains:
32|	(1) example "Call-out"s
33|	(2) example package entry code
34|	(3) example "Call-out" table
35|
36
37#include <linux/linkage.h>
38#include <asm/entry.h>
39#include <asm/asm-offsets.h>
40
41
42|################################
43| (1) EXAMPLE CALL-OUTS		#
44|				#
45| _060_isp_done()		#
46| _060_real_chk()		#
47| _060_real_divbyzero()		#
48|				#
49| _060_real_cas()		#
50| _060_real_cas2()		#
51| _060_real_lock_page()		#
52| _060_real_unlock_page()	#
53|################################
54
55|
56| _060_isp_done():
57|
58| This is and example main exit point for the Unimplemented Integer
59| Instruction exception handler. For a normal exit, the
60| _isp_unimp() branches to here so that the operating system
61| can do any clean-up desired. The stack frame is the
62| Unimplemented Integer Instruction stack frame with
63| the PC pointing to the instruction following the instruction
64| just emulated.
65| To simply continue execution at the next instruction, just
66| do an "rte".
67|
68| Linux/68k: If returning to user space, check for needed reselections.
69
70	.global		_060_isp_done
71_060_isp_done:
72	btst	#0x5,%sp@		| supervisor bit set in saved SR?
73	beq	.Lnotkern
74	rte
75.Lnotkern:
76	SAVE_ALL_INT
77	GET_CURRENT(%d0)
78	| deliver signals, reschedule etc..
79	jra	ret_from_exception
80
81|
82| _060_real_chk():
83|
84| This is an alternate exit point for the Unimplemented Integer
85| Instruction exception handler. If the instruction was a "chk2"
86| and the operand was out of bounds, then _isp_unimp() creates
87| a CHK exception stack frame from the Unimplemented Integer Instrcution
88| stack frame and branches to this routine.
89|
90| Linux/68k: commented out test for tracing
91
92	.global		_060_real_chk
93_060_real_chk:
94|	tst.b		(%sp)			| is tracing enabled?
95|	bpls		real_chk_end		| no
96
97|
98|	    CHK FRAME		   TRACE FRAME
99|	*****************	*****************
100|	*   Current PC	*	*   Current PC	*
101|	*****************	*****************
102|	* 0x2 *  0x018	*	* 0x2 *  0x024	*
103|	*****************	*****************
104|	*     Next	*	*     Next	*
105|	*      PC	*	*      PC	*
106|	*****************	*****************
107|	*      SR	*	*      SR	*
108|	*****************	*****************
109|
110|	move.b		#0x24,0x7(%sp)		| set trace vecno
111|	bral		_060_real_trace
112
113real_chk_end:
114	bral		trap			| jump to trap handler
115
116|
117| _060_real_divbyzero:
118|
119| This is an alternate exit point for the Unimplemented Integer
120| Instruction exception handler isp_unimp(). If the instruction is a 64-bit
121| integer divide where the source operand is a zero, then the _isp_unimp()
122| creates a Divide-by-zero exception stack frame from the Unimplemented
123| Integer Instruction stack frame and branches to this routine.
124|
125| Remember that a trace exception may be pending. The code below performs
126| no action associated with the "chk" exception. If tracing is enabled,
127| then it create a Trace exception stack frame from the "chk" exception
128| stack frame and branches to the _real_trace() entry point.
129|
130| Linux/68k: commented out test for tracing
131
132	.global		_060_real_divbyzero
133_060_real_divbyzero:
134|	tst.b		(%sp)			| is tracing enabled?
135|	bpls		real_divbyzero_end	| no
136
137|
138|	 DIVBYZERO FRAME	   TRACE FRAME
139|	*****************	*****************
140|	*   Current PC	*	*   Current PC	*
141|	*****************	*****************
142|	* 0x2 *  0x014	*	* 0x2 *  0x024	*
143|	*****************	*****************
144|	*     Next	*	*     Next	*
145|	*      PC	*	*      PC	*
146|	*****************	*****************
147|	*      SR	*	*      SR	*
148|	*****************	*****************
149|
150|	move.b		#0x24,0x7(%sp)		| set trace vecno
151|	bral		_060_real_trace
152
153real_divbyzero_end:
154	bral		trap			| jump to trap handler
155
156|##########################
157
158|
159| _060_real_cas():
160|
161| Entry point for the selected cas emulation code implementation.
162| If the implementation provided by the 68060ISP is sufficient,
163| then this routine simply re-enters the package through _isp_cas.
164|
165	.global		_060_real_cas
166_060_real_cas:
167	bral		_I_CALL_TOP+0x80+0x08
168
169|
170| _060_real_cas2():
171|
172| Entry point for the selected cas2 emulation code implementation.
173| If the implementation provided by the 68060ISP is sufficient,
174| then this routine simply re-enters the package through _isp_cas2.
175|
176	.global		_060_real_cas2
177_060_real_cas2:
178	bral		_I_CALL_TOP+0x80+0x10
179
180|
181| _060_lock_page():
182|
183| Entry point for the operating system`s routine to "lock" a page
184| from being paged out. This routine is needed by the cas/cas2
185| algorithms so that no page faults occur within the "core" code
186| region. Note: the routine must lock two pages if the operand
187| spans two pages.
188| NOTE: THE ROUTINE SHOULD RETURN AN FSLW VALUE IN D0 ON FAILURE
189| SO THAT THE 060SP CAN CREATE A PROPER ACCESS ERROR FRAME.
190| Arguments:
191|	a0 = operand address
192|	d0 = `xxxxxxff -> supervisor; `xxxxxx00 -> user
193|	d1 = `xxxxxxff -> longword; `xxxxxx00 -> word
194| Expected outputs:
195|	d0 = 0 -> success; non-zero -> failure
196|
197| Linux/m68k: Make sure the page is properly paged in, so we use
198| plpaw and handle any exception here. The kernel must not be
199| preempted until _060_unlock_page(), so that the page stays mapped.
200|
201	.global		_060_real_lock_page
202_060_real_lock_page:
203	move.l	%d2,-(%sp)
204	| load sfc/dfc
205	tst.b	%d0
206	jne	1f
207	moveq	#1,%d0
208	jra	2f
2091:	moveq	#5,%d0
2102:	movec.l	%dfc,%d2
211	movec.l	%d0,%dfc
212	movec.l	%d0,%sfc
213
214	clr.l	%d0
215	| prefetch address
216	.chip	68060
217	move.l	%a0,%a1
2181:	plpaw	(%a1)
219	addq.w	#1,%a0
220	tst.b	%d1
221	jeq	2f
222	addq.w	#2,%a0
2232:	plpaw	(%a0)
2243:	.chip	68k
225
226	| restore sfc/dfc
227	movec.l	%d2,%dfc
228	movec.l	%d2,%sfc
229	move.l	(%sp)+,%d2
230	rts
231
232.section __ex_table,"a"
233	.align	4
234	.long	1b,11f
235	.long	2b,21f
236.previous
237.section .fixup,"ax"
238	.even
23911:	move.l	#0x020003c0,%d0
240	or.l	%d2,%d0
241	swap	%d0
242	jra	3b
24321:	move.l	#0x02000bc0,%d0
244	or.l	%d2,%d0
245	swap	%d0
246	jra	3b
247.previous
248
249|
250| _060_unlock_page():
251|
252| Entry point for the operating system`s routine to "unlock" a
253| page that has been "locked" previously with _real_lock_page.
254| Note: the routine must unlock two pages if the operand spans
255| two pages.
256| Arguments:
257|	a0 = operand address
258|	d0 = `xxxxxxff -> supervisor; `xxxxxx00 -> user
259|	d1 = `xxxxxxff -> longword; `xxxxxx00 -> word
260|
261| Linux/m68k: perhaps reenable preemption here...
262
263	.global		_060_real_unlock_page
264_060_real_unlock_page:
265	clr.l		%d0
266	rts
267
268|###########################################################################
269
270|#################################
271| (2) EXAMPLE PACKAGE ENTRY CODE #
272|#################################
273
274	.global		_060_isp_unimp
275_060_isp_unimp:
276	bral		_I_CALL_TOP+0x80+0x00
277
278	.global		_060_isp_cas
279_060_isp_cas:
280	bral		_I_CALL_TOP+0x80+0x08
281
282	.global		_060_isp_cas2
283_060_isp_cas2:
284	bral		_I_CALL_TOP+0x80+0x10
285
286	.global		_060_isp_cas_finish
287_060_isp_cas_finish:
288	bra.l		_I_CALL_TOP+0x80+0x18
289
290	.global		_060_isp_cas2_finish
291_060_isp_cas2_finish:
292	bral		_I_CALL_TOP+0x80+0x20
293
294	.global		_060_isp_cas_inrange
295_060_isp_cas_inrange:
296	bral		_I_CALL_TOP+0x80+0x28
297
298	.global		_060_isp_cas_terminate
299_060_isp_cas_terminate:
300	bral		_I_CALL_TOP+0x80+0x30
301
302	.global		_060_isp_cas_restart
303_060_isp_cas_restart:
304	bral		_I_CALL_TOP+0x80+0x38
305
306|###########################################################################
307
308|###############################
309| (3) EXAMPLE CALL-OUT SECTION #
310|###############################
311
312| The size of this section MUST be 128 bytes!!!
313
314_I_CALL_TOP:
315	.long	_060_real_chk		- _I_CALL_TOP
316	.long	_060_real_divbyzero	- _I_CALL_TOP
317	.long	_060_real_trace		- _I_CALL_TOP
318	.long	_060_real_access	- _I_CALL_TOP
319	.long	_060_isp_done		- _I_CALL_TOP
320
321	.long	_060_real_cas		- _I_CALL_TOP
322	.long	_060_real_cas2		- _I_CALL_TOP
323	.long	_060_real_lock_page	- _I_CALL_TOP
324	.long	_060_real_unlock_page	- _I_CALL_TOP
325
326	.long	0x00000000, 0x00000000, 0x00000000, 0x00000000
327	.long	0x00000000, 0x00000000, 0x00000000
328
329	.long	_060_imem_read		- _I_CALL_TOP
330	.long	_060_dmem_read		- _I_CALL_TOP
331	.long	_060_dmem_write		- _I_CALL_TOP
332	.long	_060_imem_read_word	- _I_CALL_TOP
333	.long	_060_imem_read_long	- _I_CALL_TOP
334	.long	_060_dmem_read_byte	- _I_CALL_TOP
335	.long	_060_dmem_read_word	- _I_CALL_TOP
336	.long	_060_dmem_read_long	- _I_CALL_TOP
337	.long	_060_dmem_write_byte	- _I_CALL_TOP
338	.long	_060_dmem_write_word	- _I_CALL_TOP
339	.long	_060_dmem_write_long	- _I_CALL_TOP
340
341	.long	0x00000000
342	.long	0x00000000, 0x00000000, 0x00000000, 0x00000000
343
344|###########################################################################
345
346| 060 INTEGER KERNEL PACKAGE MUST GO HERE!!!
347#include "isp.sa"
348