OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [exec/] [score/] [cpu/] [i960/] [cpu_asm.S] - Blame information for rev 593

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

Line No. Rev Author Line
1 30 unneback
/*  cpu_asm.s
2
 *
3
 *  This file contains all assembly code for the i960CA implementation
4
 *  of RTEMS.
5
 *
6
 *  COPYRIGHT (c) 1989-1999.
7
 *  On-Line Applications Research Corporation (OAR).
8
 *
9
 *  The license and distribution terms for this file may be
10
 *  found in the file LICENSE in this distribution or at
11
 *  http://www.OARcorp.com/rtems/license.html.
12
 *
13
 *  $Id: cpu_asm.S,v 1.2 2001-09-27 11:59:27 chris Exp $
14
 */
15
        .data
16
        .align 4
17
_soft_reset_reg_save:
18
        .word  0
19
        .word  0
20
        .word  0
21
        .word  0
22
_ISR_reg_save:
23
        .word  0
24
        .word  0
25
        .word  0
26
        .word  0
27
        .word  0
28
        .word  0
29
 
30
          .text
31
/*
32
 * Format of i960ca Register structure
33
 */
34
 
35
.set REG_R0_PFP    , 0                # (r0)  Previous Frame Pointer
36
.set REG_R1_SP     , REG_R0_PFP+4     # (r1)  Stack Pointer
37
.set REG_PC        , REG_R1_SP+4      # (pc)  Processor Controls
38
.set REG_G8        , REG_PC+4         # (g8)  Global Register 8
39
.set REG_G9        , REG_G8+4         # (g9)  Global Register 9
40
.set REG_G10       , REG_G9+4         # (g10) Global Register 10
41
.set REG_G11       , REG_G10+4        # (g11) Global Register 11
42
.set REG_G12       , REG_G11+4        # (g12) Global Register 12
43
.set REG_G13       , REG_G12+4        # (g13) Global Register 13
44
.set REG_G14       , REG_G13+4        # (g14) Global Register 14
45
.set REG_G15_FP    , REG_G14+4        # (g15) Global Register 15
46
.set SIZE_REGS     , REG_G15_FP+4     # size of cpu_context_registers
47
                                      #    structure
48
 
49
/*
50
 *  void _CPU_Context_switch( run_context, heir_context )
51
 *
52
 *  This routine performs a normal non-FP context.
53
 */
54
          .align    4
55
          .globl    __CPU_Context_switch
56
 
57
__CPU_Context_switch:
58
          modpc     0,0,g2                   # get old intr level (PC)
59
          st        g2,REG_PC(g0)            # save pc
60
          stq       g8,REG_G8(g0)            # save g8-g11
61
          stq       g12,REG_G12(g0)          # save g12-g15
62
          stl       pfp,REG_R0_PFP(g0)       # save pfp, sp
63
 
64
restore:  flushreg                           # flush register cache
65
          ldconst   0x001f0000,g2            # g2 = PC mask
66
          ld        REG_PC(g1),g3            # thread->Regs.pc = pc;
67
          ldq       REG_G12(g1),g12          # restore g12-g15
68
          ldl       REG_R0_PFP(g1),pfp       # restore pfp, sp
69
          ldq       REG_G8(g1),g8            # restore g8-g11
70
          modpc     0,g2,g3                  # restore PC register
71
          ret
72
 
73
/*
74
 *  void _CPU_Context_restore( new_context )
75
 *
76
 *  This routine performs a normal non-FP context.
77
 */
78
 
79
        .globl __CPU_Context_restore
80
__CPU_Context_restore:
81
          mov       g0,g1                    # g0 = _Thread_executing
82
          b         restore
83
 
84
/*PAGE
85
 *  void _CPU_Context_save_fp_context( &fp_context_ptr )
86
 *  void _CPU_Context_restore_fp_context( &fp_context_ptr )
87
 *
88
 *  There is currently no hardware floating point for the i960.
89
 */
90
 
91
          .globl    __CPU_Context_save_fp
92
          .globl    __CPU_Context_restore_fp
93
__CPU_Context_save_fp:
94
__CPU_Context_restore_fp:
95
#if ( I960_HAS_FPU == 1 )
96
#error "Floating point support for i960 family has been implemented!!!"
97
#endif
98
          ret
99
 
100
/*PAGE
101
 *  void __ISR_Handler()
102
 *
103
 *  This routine provides the RTEMS interrupt management.
104
 *
105
 *  Input parameters:  NONE
106
 *
107
 *  Output parameters:  NONE
108
 *
109
 *  NOTE:
110
 *    Upon entry, the supervisor stack will contain a stack frame
111
 *    back to the interrupted thread and the interrupt stack will contain
112
 *    an interrupt stack frame.  If dispatching is enabled, this
113
 *    is the outer most interrupt, and (a context switch is necessary or
114
 *    the current thread has signals), then set up the supervisor stack to
115
 *    transfer control to the interrupt dispatcher.
116
 */
117
 
118
          .globl    __ISR_Handler
119
__ISR_Handler:
120
          #ldconst 1,r8
121
          #modpc   0,r8,r8     # enable tracing
122
 
123
                               # r4 = &_Thread_Dispatch_disable_level
124
          ld         __Thread_Dispatch_disable_level,r4
125
          movl      g0,r8                    # save g0-g1
126
 
127
          ld        -16+8(fp),g0             # g0 = vector number
128
          movl      g2,r10                   # save g2-g3
129
 
130
          ld         __ISR_Nest_level,r5     # r5 = &_Isr_nest_level
131
          mov       g14,r7                   # save g14
132
 
133
          lda       0,g14                    # NOT Branch and Link
134
          movl      g4,r12                   # save g4-g5
135
 
136
          lda       1(r4),r4                 # increment dispatch disable level
137
          movl      g6,r14                   # save g6-g7
138
 
139
                  stq           g8, _ISR_reg_save                # save g8-g11
140
                  stl           g12, _ISR_reg_save+16    # save g12-g13
141
 
142
          ld        __ISR_Vector_table[g0*4],g1    # g1 = Users handler
143
          addo      1,r5,r5                  # increment ISR level
144
 
145
          st        r4,__Thread_Dispatch_disable_level
146
                                             # one ISR nest level deeper
147
          subo      1,r4,r4                  # decrement dispatch disable level
148
 
149
          st        r5,__ISR_Nest_level      # disable multitasking
150
          subo      1,r5,r5                  # decrement ISR nest level
151
 
152
          callx     (g1)                     # invoke user ISR
153
 
154
                                             # unnest multitasking
155
          st        r5,__ISR_Nest_level      # one less ISR nest level
156
          cmpobne.f 0,r4,exit                # If dispatch disabled, exit
157
          ldl       -16(fp),g0               # g0 = threads PC reg
158
                                             # g1 = threads AC reg
159
          ld        __Context_Switch_necessary,r6
160
                                             # r6 = Is thread switch necessary?
161
          bbs.f     13,g0,exit               # not outer level, then exit
162
          cmpobne.f 0,r6,bframe              # Switch necessary?
163
 
164
          ld        __ISR_Signals_to_thread_executing,g2
165
                                             # signals sent to Run_thread
166
                                             #   while in interrupt handler?
167
          cmpobe.f  0,g2,exit                # No, then exit
168
 
169
bframe:   mov       0,g2
170
          st        g2,__ISR_Signals_to_thread_executing
171
 
172
          ldconst   0x1f0000,g2              # g2 = intr disable mask
173
          mov       g2,g3                    # g3 = new intr level
174
          modpc     0,g2,g3                  # set new level
175
 
176
          andnot    7,pfp,r4                 # r4 = pfp without ret type
177
          flushreg                           # flush registers
178
                                             # push _Isr_dispatch ret frame
179
                                             #   build ISF in r4-r6
180
          ldconst   64,g2                    # g2 = size of stack frame
181
          ld        4(r4),g3                 # g3 = previous sp
182
          addo      g2,g3,r5                 # r5 = _Isr_dispatch SP
183
          lda       __ISR_Dispatch,r6        # r6 = _Isr_dispatch entry
184
          stt       r4,(g3)                  # set _Isr_dispatch ret info
185
          st        g1,16(g3)                # set r4 = AC for ISR disp
186
          or        7,g3,pfp                 # pfp to _Isr_dispatch
187
          flushreg
188
          b         exit1
189
exit:     st        r4,__Thread_Dispatch_disable_level
190
exit1:    mov       r7,g14                   # restore g14
191
          movq      r8,g0                    # restore g0-g3
192
          movq      r12,g4                   # restore g4-g7
193
                  ldq           _ISR_reg_save, g8                # restore g8-g11
194
                  ldl           _ISR_reg_save+16, g12    # restore g12-g13
195
          ret
196
 
197
 
198
/*PAGE
199
 *
200
 *  void __ISR_Dispatch()
201
 *
202
 *  Entry point from the outermost interrupt service routine exit.
203
 *  The current stack is the supervisor mode stack.
204
 */
205
 
206
__ISR_Dispatch:
207
        mov       g14,r7
208
        mov       0,g14
209
        movq      g0,r8
210
        movq      g4,r12
211
        call      __Thread_Dispatch
212
 
213
        ldconst   -1,r5                    # r5 = reload mask
214
        modac     r5,r4,r4                 # restore threads AC register
215
        mov       r7,g14
216
        movq      r8,g0
217
        movq      r12,g4
218
        ret
219
 
220
 
221
/*PAGE
222
 *
223
 *  void __i960_soft_reset_asm
224
 *
225
 *  Flush the register cache and save the important (fp, pfp, sp) registers,
226
 *  which are clobbered by the reinit operation. (Not documented, but it happens).
227
 */
228
 
229
#if !defined(__i960KA__)
230
                .globl __i960_soft_reset_asm
231
__i960_soft_reset_asm:
232
                flushreg                                                                # flush register cache
233
                mov                     fp, r4
234
                mov                     pfp, r5
235
                mov                     sp, r6
236
                stt                     r4, _soft_reset_reg_save    # save fp, pfp, sp
237
                lda                     __i960_reset_done, r4
238
                ldconst         0x300, r5
239
                sysctl          r5, r4, g0                  # reinit: clobbers almost all registers
240
__i960_reset_done:
241
                ldt             _soft_reset_reg_save, r4    # restore fp, pfp, sp
242
                mov                     r4, fp
243
                mov                     r5, pfp
244
                mov                     r6, sp
245
                ret
246
#endif

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.