URL https://opencores.org/ocsvn/eco32/eco32/trunk

Subversion Repositories eco32

[/] [eco32/] [trunk/] [monitor/] [monitor/] [boards/] [s3e-500/] [start.s] - Blame information for rev 156

Go to most recent revision | Details | Compare with Previous | View Log


;
; start.s -- ECO32 ROM monitor startup and support routines
;
 
        .set    dmapaddr,0xC0000000     ; base of directly mapped addresses
        .set    stacktop,0xC0010000     ; monitor stack is at top of 64K
 
        .set    PSW,0                    ; reg # of PSW
        .set    V_SHIFT,27              ; interrupt vector ctrl bit
        .set    V,1 << V_SHIFT
 
        .set    TLB_INDEX,1             ; reg # of TLB Index
        .set    TLB_ENTRY_HI,2          ; reg # of TLB EntryHi
        .set    TLB_ENTRY_LO,3          ; reg # of TLB EntryLo
        .set    TLB_ENTRIES,32          ; number of TLB entries
        .set    BAD_ADDRESS,4           ; reg # of bad address reg
 
        .set    USER_CONTEXT_SIZE,37*4  ; size of user context
 
        .set    BIO_OUT,0xF1000000      ; board I/O output port
        .set    SPI_EN,0x80000000       ; SPI bus enable ctrl bit
 
;***************************************************************
 
        .import _ecode
        .import _edata
        .import _ebss
 
        .import kbdinit
        .import kbdinchk
        .import kbdin
 
        .import dspinit
        .import dspoutchk
        .import dspout
 
        .import serinit
        .import ser0inchk
        .import ser0in
        .import ser0outchk
        .import ser0out
 
        .import sctcapctl
        .import sctioctl
        .import sctcapser
        .import sctioser
 
        .import main
 
        .export _bcode
        .export _bdata
        .export _bbss
 
        .export cinchk
        .export cin
        .export coutchk
        .export cout
        .export sinchk
        .export sin
        .export soutchk
        .export sout
        .export dskcap
        .export dskio
 
        .export setISR
        .export setUMSR
        .export isrPtr
        .export umsrPtr
 
        .export getTLB_HI
        .export getTLB_LO
        .export setTLB
 
        .export saveState
        .export monitorReturn
 
        .import userContext
        .export resume
 
;***************************************************************
 
        .code
_bcode:
 
        .data
_bdata:
 
        .bss
_bbss:
 
;***************************************************************
 
        .code
        .align  4
 
reset:
        j       start
 
interrupt:
        j       isr
 
userMiss:
        j       umsr
 
;***************************************************************
 
        .code
        .align  4
 
cinchk:
        j       kbdinchk
;       j       ser0inchk
 
cin:
        j       kbdin
;       j       ser0in
 
coutchk:
        j       dspoutchk
;       j       ser0outchk
 
cout:
        j       dspout
;       j       ser0out
 
sinchk:
        j       ser0inchk
 
sin:
        j       ser0in
 
soutchk:
        j       ser0outchk
 
sout:
        j       ser0out
 
dskcap:
        j       dcap
 
dskio:
        j       dio
 
reserved1:
        j       reserved1
 
reserved2:
        j       reserved2
 
reserved3:
        j       reserved3
 
setISR:
        j       setISR1
 
setUMSR:
        j       setUMSR1
 
;***************************************************************
 
        .code
        .align  4
 
start:
        ; let irq/exc vectors point to RAM
        add     $8,$0,V
        mvts    $8,PSW
 
        ; disable flash ROM, enable SPI bus
        add     $8,$0,BIO_OUT
        add     $9,$0,SPI_EN
        stw     $9,$8,0
 
        ; initialize TLB
        mvts    $0,TLB_ENTRY_LO          ; invalidate all TLB entries
        add     $8,$0,dmapaddr           ; by impossible virtual page number
        add     $9,$0,$0
        add     $10,$0,TLB_ENTRIES
tlbloop:
        mvts    $8,TLB_ENTRY_HI
        mvts    $9,TLB_INDEX
        tbwi
        add     $8,$8,0x1000            ; all entries must be different
        add     $9,$9,1
        bne     $9,$10,tlbloop
 
        ; copy data segment
        add     $10,$0,_bdata            ; lowest dst addr to be written to
        add     $8,$0,_edata             ; one above the top dst addr
        sub     $9,$8,$10               ; $9 = size of data segment
        add     $9,$9,_ecode            ; data is waiting right after code
        j       cpytest
cpyloop:
        ldw     $11,$9,0         ; src addr in $9
        stw     $11,$8,0         ; dst addr in $8
cpytest:
        sub     $8,$8,4                 ; downward
        sub     $9,$9,4
        bgeu    $8,$10,cpyloop
 
        ; clear bss segment
        add     $8,$0,_bbss              ; start with first word of bss
        add     $9,$0,_ebss              ; this is one above the top
        j       clrtest
clrloop:
        stw     $0,$8,0                   ; dst addr in $8
        add     $8,$8,4                 ; upward
clrtest:
        bltu    $8,$9,clrloop
 
        ; now do some useful work
        add     $29,$0,stacktop          ; setup monitor stack
        jal     dspinit                 ; init display
        jal     kbdinit                 ; init keyboard
        jal     serinit                 ; init serial interface
        jal     main                    ; enter command loop
 
        ; main should never return
        j       start                   ; just to be sure...
 
;***************************************************************
 
        .code
        .align  4
 
        ; Word getTLB_HI(int index)
getTLB_HI:
        mvts    $4,TLB_INDEX
        tbri
        mvfs    $2,TLB_ENTRY_HI
        jr      $31
 
        ; Word getTLB_LO(int index)
getTLB_LO:
        mvts    $4,TLB_INDEX
        tbri
        mvfs    $2,TLB_ENTRY_LO
        jr      $31
 
        ; void setTLB(int index, Word entryHi, Word entryLo)
setTLB:
        mvts    $4,TLB_INDEX
        mvts    $5,TLB_ENTRY_HI
        mvts    $6,TLB_ENTRY_LO
        tbwi
        jr      $31
 
;***************************************************************
 
        .code
        .align  4
 
        ; int dskcap(int dskno)
dcap:
        bne     $4,$0,dcapser
        j       sctcapctl
dcapser:
        j       sctcapser
 
        ; int dskio(int dskno, char cmd, int sct, Word addr, int nscts)
dio:
        bne     $4,$0,dioser
        add     $4,$5,$0
        add     $5,$6,$0
        add     $6,$7,$0
        ldw     $7,$29,16
        j       sctioctl
dioser:
        add     $4,$5,$0
        add     $5,$6,$0
        add     $6,$7,$0
        ldw     $7,$29,16
        j       sctioser
 
;***************************************************************
 
        .code
        .align  4
 
        ; void setISR(Word ptr)
setISR1:
        stw     $4,$0,isrPtr
        jr      $31
 
        ; void setUMSR(Word ptr)
setUMSR1:
        stw     $4,$0,umsrPtr
        jr      $31
 
        .data
        .align  4
 
isrPtr:
        .word   0
 
umsrPtr:
        .word   0
 
;***************************************************************
 
        .code
        .align  4
 
        ; Bool saveState(MonitorState *msp)
        ; always return 'true' here
saveState:
        stw     $31,$4,0*4               ; return address
        stw     $29,$4,1*4              ; stack pointer
        stw     $16,$4,2*4              ; local variables
        stw     $17,$4,3*4
        stw     $18,$4,4*4
        stw     $19,$4,5*4
        stw     $20,$4,6*4
        stw     $21,$4,7*4
        stw     $22,$4,8*4
        stw     $23,$4,9*4
        add     $2,$0,1
        jr      $31
 
        ; load state when re-entering monitor
        ; this appears as if returning from saveState
        ; but the return value is 'false' here
loadState:
        ldw     $8,$0,monitorReturn
        beq     $8,$0,loadState          ; fatal error: monitor state lost
        ldw     $31,$8,0*4               ; return address
        ldw     $29,$8,1*4              ; stack pointer
        ldw     $16,$8,2*4              ; local variables
        ldw     $17,$8,3*4
        ldw     $18,$8,4*4
        ldw     $19,$8,5*4
        ldw     $20,$8,6*4
        ldw     $21,$8,7*4
        ldw     $22,$8,8*4
        ldw     $23,$8,9*4
        add     $2,$0,0
        jr      $31
 
        .bss
        .align  4
 
        ; extern MonitorState *monitorReturn
monitorReturn:
        .space  4
 
        ; extern UserContext userContext
userContext:
        .space  USER_CONTEXT_SIZE
 
;***************************************************************
 
        .code
        .align  4
 
        ; void resume(void)
        ; use userContext to load state
resume:
        mvts    $0,PSW
        add     $28,$0,userContext
        .nosyn
        ldw     $8,$28,33*4             ; tlbIndex
        mvts    $8,TLB_INDEX
        ldw     $8,$28,34*4             ; tlbEntryHi
        mvts    $8,TLB_ENTRY_HI
        ldw     $8,$28,35*4             ; tlbEntryLo
        mvts    $8,TLB_ENTRY_LO
        ldw     $8,$28,36*4             ; badAddress
        mvts    $8,BAD_ADDRESS
        ;ldw    $0,$28,0*4              ; registers
        ldw     $1,$28,1*4
        ldw     $2,$28,2*4
        ldw     $3,$28,3*4
        ldw     $4,$28,4*4
        ldw     $5,$28,5*4
        ldw     $6,$28,6*4
        ldw     $7,$28,7*4
        ldw     $8,$28,8*4
        ldw     $9,$28,9*4
        ldw     $10,$28,10*4
        ldw     $11,$28,11*4
        ldw     $12,$28,12*4
        ldw     $13,$28,13*4
        ldw     $14,$28,14*4
        ldw     $15,$28,15*4
        ldw     $16,$28,16*4
        ldw     $17,$28,17*4
        ldw     $18,$28,18*4
        ldw     $19,$28,19*4
        ldw     $20,$28,20*4
        ldw     $21,$28,21*4
        ldw     $22,$28,22*4
        ldw     $23,$28,23*4
        ldw     $24,$28,24*4
        ldw     $25,$28,25*4
        ldw     $26,$28,26*4
        ldw     $27,$28,27*4
        ;ldw    $28,$28,28*4
        ldw     $29,$28,29*4
        ldw     $30,$28,30*4
        ldw     $31,$28,31*4
        ldw     $28,$28,32*4            ; psw
        mvts    $28,PSW
        rfx
        .syn
 
        ; interrupt entry
        ; use userContext to store state
isr:
umsr:
        .nosyn
        ldhi    $28,userContext
        or      $28,$28,userContext
        stw     $0,$28,0*4                ; registers
        stw     $1,$28,1*4
        stw     $2,$28,2*4
        stw     $3,$28,3*4
        stw     $4,$28,4*4
        stw     $5,$28,5*4
        stw     $6,$28,6*4
        stw     $7,$28,7*4
        stw     $8,$28,8*4
        stw     $9,$28,9*4
        stw     $10,$28,10*4
        stw     $11,$28,11*4
        stw     $12,$28,12*4
        stw     $13,$28,13*4
        stw     $14,$28,14*4
        stw     $15,$28,15*4
        stw     $16,$28,16*4
        stw     $17,$28,17*4
        stw     $18,$28,18*4
        stw     $19,$28,19*4
        stw     $20,$28,20*4
        stw     $21,$28,21*4
        stw     $22,$28,22*4
        stw     $23,$28,23*4
        stw     $24,$28,24*4
        stw     $25,$28,25*4
        stw     $26,$28,26*4
        stw     $27,$28,27*4
        stw     $28,$28,28*4
        stw     $29,$28,29*4
        stw     $30,$28,30*4
        stw     $31,$28,31*4
        mvfs    $8,PSW
        stw     $8,$28,32*4             ; psw
        mvfs    $8,TLB_INDEX
        stw     $8,$28,33*4             ; tlbIndex
        mvfs    $8,TLB_ENTRY_HI
        stw     $8,$28,34*4             ; tlbEntryHi
        mvfs    $8,TLB_ENTRY_LO
        stw     $8,$28,35*4             ; tlbEntryLo
        mvfs    $8,BAD_ADDRESS
        stw     $8,$28,36*4             ; badAddress
        .syn
        j       loadState

Browse

Tools

Subversion Repositories eco32

[/] [eco32/] [trunk/] [monitor/] [monitor/] [boards/] [s3e-500/] [start.s] - Blame information for rev 156

Line No.	Rev	Author	Line
1	16	hellwig	`;`
2			`; start.s -- ECO32 ROM monitor startup and support routines`
3			`;`
4
5			`.set dmapaddr,0xC0000000 ; base of directly mapped addresses`
6	50	hellwig	`.set stacktop,0xC0010000 ; monitor stack is at top of 64K`
7	16	hellwig
8			`.set PSW,0 ; reg # of PSW`
9	50	hellwig	`.set V_SHIFT,27 ; interrupt vector ctrl bit`
10			`.set V,1 << V_SHIFT`
11
12	16	hellwig	`.set TLB_INDEX,1 ; reg # of TLB Index`
13			`.set TLB_ENTRY_HI,2 ; reg # of TLB EntryHi`
14			`.set TLB_ENTRY_LO,3 ; reg # of TLB EntryLo`
15			`.set TLB_ENTRIES,32 ; number of TLB entries`
16	84	hellwig	`.set BAD_ADDRESS,4 ; reg # of bad address reg`
17	16	hellwig
18	84	hellwig	`.set USER_CONTEXT_SIZE,37*4 ; size of user context`
19	16	hellwig
20	50	hellwig	`.set BIO_OUT,0xF1000000 ; board I/O output port`
21			`.set SPI_EN,0x80000000 ; SPI bus enable ctrl bit`
22
23	16	hellwig	`;***************************************************************`
24
25			`.import _ecode`
26			`.import _edata`
27			`.import _ebss`
28
29			`.import kbdinit`
30			`.import kbdinchk`
31			`.import kbdin`
32
33			`.import dspinit`
34			`.import dspoutchk`
35			`.import dspout`
36
37			`.import serinit`
38			`.import ser0inchk`
39			`.import ser0in`
40			`.import ser0outchk`
41			`.import ser0out`
42
43			`.import sctcapctl`
44			`.import sctioctl`
45			`.import sctcapser`
46			`.import sctioser`
47
48			`.import main`
49
50			`.export _bcode`
51			`.export _bdata`
52			`.export _bbss`
53
54			`.export cinchk`
55			`.export cin`
56			`.export coutchk`
57			`.export cout`
58			`.export sinchk`
59			`.export sin`
60			`.export soutchk`
61			`.export sout`
62			`.export dskcap`
63			`.export dskio`
64
65	50	hellwig	`.export setISR`
66			`.export setUMSR`
67			`.export isrPtr`
68			`.export umsrPtr`
69
70	16	hellwig	`.export getTLB_HI`
71			`.export getTLB_LO`
72			`.export setTLB`
73
74			`.export saveState`
75			`.export monitorReturn`
76
77			`.import userContext`
78			`.export resume`
79
80			`;***************************************************************`
81
82			`.code`
83			`_bcode:`
84
85			`.data`
86			`_bdata:`
87
88			`.bss`
89			`_bbss:`
90
91			`;***************************************************************`
92
93			`.code`
94			`.align 4`
95
96			`reset:`
97			`j start`
98
99			`interrupt:`
100			`j isr`
101
102			`userMiss:`
103			`j umsr`
104
105			`;***************************************************************`
106
107			`.code`
108			`.align 4`
109
110			`cinchk:`
111			`j kbdinchk`
112			`; j ser0inchk`
113
114			`cin:`
115			`j kbdin`
116			`; j ser0in`
117
118			`coutchk:`
119			`j dspoutchk`
120			`; j ser0outchk`
121
122			`cout:`
123			`j dspout`
124			`; j ser0out`
125
126			`sinchk:`
127			`j ser0inchk`
128
129			`sin:`
130			`j ser0in`
131
132			`soutchk:`
133			`j ser0outchk`
134
135			`sout:`
136			`j ser0out`
137
138			`dskcap:`
139			`j dcap`
140
141			`dskio:`
142			`j dio`
143
144	50	hellwig	`reserved1:`
145			`j reserved1`
146
147			`reserved2:`
148			`j reserved2`
149
150			`reserved3:`
151			`j reserved3`
152
153			`setISR:`
154			`j setISR1`
155
156			`setUMSR:`
157			`j setUMSR1`
158
159	16	hellwig	`;***************************************************************`
160
161			`.code`
162			`.align 4`
163
164			`start:`
165	50	hellwig	`; let irq/exc vectors point to RAM`
166			`add $8,$0,V`
167			`mvts $8,PSW`
168	16	hellwig
169	50	hellwig	`; disable flash ROM, enable SPI bus`
170			`add $8,$0,BIO_OUT`
171			`add $9,$0,SPI_EN`
172			`stw $9,$8,0`
173
174	16	hellwig	`; initialize TLB`
175			`mvts $0,TLB_ENTRY_LO ; invalidate all TLB entries`
176			`add $8,$0,dmapaddr ; by impossible virtual page number`
177			`add $9,$0,$0`
178			`add $10,$0,TLB_ENTRIES`
179			`tlbloop:`
180			`mvts $8,TLB_ENTRY_HI`
181			`mvts $9,TLB_INDEX`
182			`tbwi`
183			`add $8,$8,0x1000 ; all entries must be different`
184			`add $9,$9,1`
185			`bne $9,$10,tlbloop`
186
187			`; copy data segment`
188			`add $10,$0,_bdata ; lowest dst addr to be written to`
189			`add $8,$0,_edata ; one above the top dst addr`
190			`sub $9,$8,$10 ; $9 = size of data segment`
191			`add $9,$9,_ecode ; data is waiting right after code`
192			`j cpytest`
193			`cpyloop:`
194			`ldw $11,$9,0 ; src addr in $9`
195			`stw $11,$8,0 ; dst addr in $8`
196			`cpytest:`
197			`sub $8,$8,4 ; downward`
198			`sub $9,$9,4`
199			`bgeu $8,$10,cpyloop`
200
201			`; clear bss segment`
202			`add $8,$0,_bbss ; start with first word of bss`
203			`add $9,$0,_ebss ; this is one above the top`
204			`j clrtest`
205			`clrloop:`
206			`stw $0,$8,0 ; dst addr in $8`
207			`add $8,$8,4 ; upward`
208			`clrtest:`
209			`bltu $8,$9,clrloop`
210
211			`; now do some useful work`
212			`add $29,$0,stacktop ; setup monitor stack`
213			`jal dspinit ; init display`
214			`jal kbdinit ; init keyboard`
215			`jal serinit ; init serial interface`
216			`jal main ; enter command loop`
217
218			`; main should never return`
219			`j start ; just to be sure...`
220
221			`;***************************************************************`
222
223	50	hellwig	`.code`
224			`.align 4`
225
226	16	hellwig	`; Word getTLB_HI(int index)`
227			`getTLB_HI:`
228			`mvts $4,TLB_INDEX`
229			`tbri`
230			`mvfs $2,TLB_ENTRY_HI`
231			`jr $31`
232
233			`; Word getTLB_LO(int index)`
234			`getTLB_LO:`
235			`mvts $4,TLB_INDEX`
236			`tbri`
237			`mvfs $2,TLB_ENTRY_LO`
238			`jr $31`
239
240			`; void setTLB(int index, Word entryHi, Word entryLo)`
241			`setTLB:`
242			`mvts $4,TLB_INDEX`
243			`mvts $5,TLB_ENTRY_HI`
244			`mvts $6,TLB_ENTRY_LO`
245			`tbwi`
246			`jr $31`
247
248			`;***************************************************************`
249
250	50	hellwig	`.code`
251			`.align 4`
252
253	16	hellwig	`; int dskcap(int dskno)`
254			`dcap:`
255			`bne $4,$0,dcapser`
256			`j sctcapctl`
257			`dcapser:`
258			`j sctcapser`
259
260			`; int dskio(int dskno, char cmd, int sct, Word addr, int nscts)`
261			`dio:`
262			`bne $4,$0,dioser`
263			`add $4,$5,$0`
264			`add $5,$6,$0`
265			`add $6,$7,$0`
266			`ldw $7,$29,16`
267			`j sctioctl`
268			`dioser:`
269			`add $4,$5,$0`
270			`add $5,$6,$0`
271			`add $6,$7,$0`
272			`ldw $7,$29,16`
273			`j sctioser`
274
275			`;***************************************************************`
276
277			`.code`
278			`.align 4`
279
280	50	hellwig	`; void setISR(Word ptr)`
281			`setISR1:`
282			`stw $4,$0,isrPtr`
283			`jr $31`
284
285			`; void setUMSR(Word ptr)`
286			`setUMSR1:`
287			`stw $4,$0,umsrPtr`
288			`jr $31`
289
290			`.data`
291			`.align 4`
292
293			`isrPtr:`
294			`.word 0`
295
296			`umsrPtr:`
297			`.word 0`
298
299			`;***************************************************************`
300
301			`.code`
302			`.align 4`
303
304	16	hellwig	`; Bool saveState(MonitorState *msp)`
305			`; always return 'true' here`
306			`saveState:`
307			`stw $31,$4,0*4 ; return address`
308			`stw $29,$4,1*4 ; stack pointer`
309			`stw $16,$4,2*4 ; local variables`
310			`stw $17,$4,3*4`
311			`stw $18,$4,4*4`
312			`stw $19,$4,5*4`
313			`stw $20,$4,6*4`
314			`stw $21,$4,7*4`
315			`stw $22,$4,8*4`
316			`stw $23,$4,9*4`
317			`add $2,$0,1`
318			`jr $31`
319
320			`; load state when re-entering monitor`
321			`; this appears as if returning from saveState`
322			`; but the return value is 'false' here`
323			`loadState:`
324			`ldw $8,$0,monitorReturn`
325			`beq $8,$0,loadState ; fatal error: monitor state lost`
326			`ldw $31,$8,0*4 ; return address`
327			`ldw $29,$8,1*4 ; stack pointer`
328			`ldw $16,$8,2*4 ; local variables`
329			`ldw $17,$8,3*4`
330			`ldw $18,$8,4*4`
331			`ldw $19,$8,5*4`
332			`ldw $20,$8,6*4`
333			`ldw $21,$8,7*4`
334			`ldw $22,$8,8*4`
335			`ldw $23,$8,9*4`
336			`add $2,$0,0`
337			`jr $31`
338
339			`.bss`
340			`.align 4`
341
342			`; extern MonitorState *monitorReturn`
343			`monitorReturn:`
344			`.space 4`
345
346			`; extern UserContext userContext`
347			`userContext:`
348			`.space USER_CONTEXT_SIZE`
349
350			`;***************************************************************`
351
352			`.code`
353			`.align 4`
354
355			`; void resume(void)`
356			`; use userContext to load state`
357			`resume:`
358			`mvts $0,PSW`
359			`add $28,$0,userContext`
360			`.nosyn`
361			`ldw $8,$28,33*4 ; tlbIndex`
362			`mvts $8,TLB_INDEX`
363	50	hellwig	`ldw $8,$28,34*4 ; tlbEntryHi`
364	16	hellwig	`mvts $8,TLB_ENTRY_HI`
365			`ldw $8,$28,35*4 ; tlbEntryLo`
366			`mvts $8,TLB_ENTRY_LO`
367	84	hellwig	`ldw $8,$28,36*4 ; badAddress`
368			`mvts $8,BAD_ADDRESS`
369	16	hellwig	`;ldw $0,$28,0*4 ; registers`
370			`ldw $1,$28,1*4`
371			`ldw $2,$28,2*4`
372			`ldw $3,$28,3*4`
373			`ldw $4,$28,4*4`
374			`ldw $5,$28,5*4`
375			`ldw $6,$28,6*4`
376			`ldw $7,$28,7*4`
377			`ldw $8,$28,8*4`
378			`ldw $9,$28,9*4`
379			`ldw $10,$28,10*4`
380			`ldw $11,$28,11*4`
381			`ldw $12,$28,12*4`
382			`ldw $13,$28,13*4`
383			`ldw $14,$28,14*4`
384			`ldw $15,$28,15*4`
385			`ldw $16,$28,16*4`
386			`ldw $17,$28,17*4`
387			`ldw $18,$28,18*4`
388			`ldw $19,$28,19*4`
389			`ldw $20,$28,20*4`
390			`ldw $21,$28,21*4`
391			`ldw $22,$28,22*4`
392			`ldw $23,$28,23*4`
393			`ldw $24,$28,24*4`
394			`ldw $25,$28,25*4`
395			`ldw $26,$28,26*4`
396			`ldw $27,$28,27*4`
397			`;ldw $28,$28,28*4`
398			`ldw $29,$28,29*4`
399			`ldw $30,$28,30*4`
400			`ldw $31,$28,31*4`
401			`ldw $28,$28,32*4 ; psw`
402			`mvts $28,PSW`
403			`rfx`
404			`.syn`
405
406			`; interrupt entry`
407			`; use userContext to store state`
408			`isr:`
409			`umsr:`
410			`.nosyn`
411			`ldhi $28,userContext`
412			`or $28,$28,userContext`
413			`stw $0,$28,0*4 ; registers`
414			`stw $1,$28,1*4`
415			`stw $2,$28,2*4`
416			`stw $3,$28,3*4`
417			`stw $4,$28,4*4`
418			`stw $5,$28,5*4`
419			`stw $6,$28,6*4`
420			`stw $7,$28,7*4`
421			`stw $8,$28,8*4`
422			`stw $9,$28,9*4`
423			`stw $10,$28,10*4`
424			`stw $11,$28,11*4`
425			`stw $12,$28,12*4`
426			`stw $13,$28,13*4`
427			`stw $14,$28,14*4`
428			`stw $15,$28,15*4`
429			`stw $16,$28,16*4`
430			`stw $17,$28,17*4`
431			`stw $18,$28,18*4`
432			`stw $19,$28,19*4`
433			`stw $20,$28,20*4`
434			`stw $21,$28,21*4`
435			`stw $22,$28,22*4`
436			`stw $23,$28,23*4`
437			`stw $24,$28,24*4`
438			`stw $25,$28,25*4`
439			`stw $26,$28,26*4`
440			`stw $27,$28,27*4`
441			`stw $28,$28,28*4`
442			`stw $29,$28,29*4`
443			`stw $30,$28,30*4`
444			`stw $31,$28,31*4`
445			`mvfs $8,PSW`
446			`stw $8,$28,32*4 ; psw`
447			`mvfs $8,TLB_INDEX`
448			`stw $8,$28,33*4 ; tlbIndex`
449			`mvfs $8,TLB_ENTRY_HI`
450			`stw $8,$28,34*4 ; tlbEntryHi`
451			`mvfs $8,TLB_ENTRY_LO`
452			`stw $8,$28,35*4 ; tlbEntryLo`
453	84	hellwig	`mvfs $8,BAD_ADDRESS`
454			`stw $8,$28,36*4 ; badAddress`
455	16	hellwig	`.syn`
456			`j loadState`