1
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3 #ifndef __ASM_ARC_ENTRY_ARCV2_H
4 #define __ASM_ARC_ENTRY_ARCV2_H
5
6 #include <asm/asm-offsets.h>
7 #include <asm/irqflags-arcv2.h>
8 #include <asm/thread_info.h>
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49 .macro INTERRUPT_PROLOGUE
50
51 ; (A) Before jumping to Interrupt Vector, hardware micro-ops did following:
52 ; 1. SP auto-switched to kernel mode stack
53 ; 2. STATUS32.Z flag set if in U mode at time of interrupt (U:1,K:0)
54 ; 3. Auto save: (mandatory) Push PC and STAT32 on stack
55 ; hardware does even if CONFIG_ARC_IRQ_NO_AUTOSAVE
56 ; 4. Auto save: (optional) r0-r11, blink, LPE,LPS,LPC, JLI,LDI,EI
57 ;
58 ; (B) Manually saved some regs: r12,r25,r30, sp,fp,gp, ACCL pair
59
60 #ifdef CONFIG_ARC_IRQ_NO_AUTOSAVE
61 ; carve pt_regs on stack (case #3), PC/STAT32 already on stack
62 sub sp, sp, SZ_PT_REGS - 8
63
64 __SAVE_REGFILE_HARD
65 #else
66 ; carve pt_regs on stack (case #4), which grew partially already
67 sub sp, sp, PT_r0
68 #endif
69
70 __SAVE_REGFILE_SOFT
71 .endm
72
73
74 .macro EXCEPTION_PROLOGUE
75
76 ; (A) Before jumping to Exception Vector, hardware micro-ops did following:
77 ; 1. SP auto-switched to kernel mode stack
78 ; 2. STATUS32.Z flag set if in U mode at time of exception (U:1,K:0)
79 ;
80 ; (B) Manually save the complete reg file below
81
82 sub sp, sp, SZ_PT_REGS ; carve pt_regs
83
84 ; _HARD saves r10 clobbered by _SOFT as scratch hence comes first
85
86 __SAVE_REGFILE_HARD
87 __SAVE_REGFILE_SOFT
88
89 st r0, [sp] ; orig_r0
90
91 lr r10, [eret]
92 lr r11, [erstatus]
93 ST2 r10, r11, PT_ret
94
95 lr r10, [ecr]
96 lr r11, [erbta]
97 ST2 r10, r11, PT_event
98
99 ; OUTPUT: r10 has ECR expected by EV_Trap
100 .endm
101
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107
108 .macro __SAVE_REGFILE_HARD
109
110 ST2 r0, r1, PT_r0
111 ST2 r2, r3, PT_r2
112 ST2 r4, r5, PT_r4
113 ST2 r6, r7, PT_r6
114 ST2 r8, r9, PT_r8
115 ST2 r10, r11, PT_r10
116
117 st blink, [sp, PT_blink]
118
119 lr r10, [lp_end]
120 lr r11, [lp_start]
121 ST2 r10, r11, PT_lpe
122
123 st lp_count, [sp, PT_lpc]
124
125 ; skip JLI, LDI, EI for now
126 .endm
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134
135 .macro __SAVE_REGFILE_SOFT
136
137 ST2 gp, fp, PT_r26 ; gp (r26), fp (r27)
138
139 st r12, [sp, PT_sp + 4]
140 st r30, [sp, PT_sp + 8]
141
142 ; Saving pt_regs->sp correctly requires some extra work due to the way
143 ; Auto stack switch works
144 ; - U mode: retrieve it from AUX_USER_SP
145 ; - K mode: add the offset from current SP where H/w starts auto push
146 ;
147 ; 1. Utilize the fact that Z bit is set if Intr taken in U mode
148 ; 2. Upon entry SP is always saved (for any inspection, unwinding etc),
149 ; but on return, restored only if U mode
150
151 lr r10, [AUX_USER_SP] ; U mode SP
152
153 ; ISA requires ADD.nz to have same dest and src reg operands
154 mov.nz r10, sp
155 add.nz r10, r10, SZ_PT_REGS ; K mode SP
156
157 st r10, [sp, PT_sp] ; SP (pt_regs->sp)
158
159 #ifdef CONFIG_ARC_CURR_IN_REG
160 st r25, [sp, PT_user_r25]
161 GET_CURR_TASK_ON_CPU r25
162 #endif
163
164 #ifdef CONFIG_ARC_HAS_ACCL_REGS
165 ST2 r58, r59, PT_sp + 12
166 #endif
167
168 .endm
169
170
171 .macro __RESTORE_REGFILE_SOFT
172
173 LD2 gp, fp, PT_r26 ; gp (r26), fp (r27)
174
175 ld r12, [sp, PT_sp + 4]
176 ld r30, [sp, PT_sp + 8]
177
178 ; Restore SP (into AUX_USER_SP) only if returning to U mode
179 ; - for K mode, it will be implicitly restored as stack is unwound
180 ; - Z flag set on K is inverse of what hardware does on interrupt entry
181 ; but that doesn't really matter
182 bz 1f
183
184 ld r10, [sp, PT_sp] ; SP (pt_regs->sp)
185 sr r10, [AUX_USER_SP]
186 1:
187
188 #ifdef CONFIG_ARC_CURR_IN_REG
189 ld r25, [sp, PT_user_r25]
190 #endif
191
192 #ifdef CONFIG_ARC_HAS_ACCL_REGS
193 LD2 r58, r59, PT_sp + 12
194 #endif
195 .endm
196
197
198 .macro __RESTORE_REGFILE_HARD
199
200 ld blink, [sp, PT_blink]
201
202 LD2 r10, r11, PT_lpe
203 sr r10, [lp_end]
204 sr r11, [lp_start]
205
206 ld r10, [sp, PT_lpc] ; lp_count can't be target of LD
207 mov lp_count, r10
208
209 LD2 r0, r1, PT_r0
210 LD2 r2, r3, PT_r2
211 LD2 r4, r5, PT_r4
212 LD2 r6, r7, PT_r6
213 LD2 r8, r9, PT_r8
214 LD2 r10, r11, PT_r10
215 .endm
216
217
218
219 .macro INTERRUPT_EPILOGUE
220
221 ; INPUT: r0 has STAT32 of calling context
222 ; INPUT: Z flag set if returning to K mode
223
224 ; _SOFT clobbers r10 restored by _HARD hence the order
225
226 __RESTORE_REGFILE_SOFT
227
228 #ifdef CONFIG_ARC_IRQ_NO_AUTOSAVE
229 __RESTORE_REGFILE_HARD
230 add sp, sp, SZ_PT_REGS - 8
231 #else
232 add sp, sp, PT_r0
233 #endif
234
235 .endm
236
237
238 .macro EXCEPTION_EPILOGUE
239
240 ; INPUT: r0 has STAT32 of calling context
241
242 btst r0, STATUS_U_BIT ; Z flag set if K, used in restoring SP
243
244 ld r10, [sp, PT_event + 4]
245 sr r10, [erbta]
246
247 LD2 r10, r11, PT_ret
248 sr r10, [eret]
249 sr r11, [erstatus]
250
251 __RESTORE_REGFILE_SOFT
252 __RESTORE_REGFILE_HARD
253
254 add sp, sp, SZ_PT_REGS
255 .endm
256
257 .macro FAKE_RET_FROM_EXCPN
258 lr r9, [status32]
259 bic r9, r9, STATUS_AE_MASK
260 or r9, r9, STATUS_IE_MASK
261 kflag r9
262 .endm
263
264
265 .macro GET_CURR_THR_INFO_FROM_SP reg
266 bmskn \reg, sp, THREAD_SHIFT - 1
267 .endm
268
269
270 .macro GET_CPU_ID reg
271 lr \reg, [identity]
272 xbfu \reg, \reg, 0xE8
273
274 .endm
275
276 #endif