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ca54502b MS |
1 | /* |
2 | * Low-level system-call handling, trap handlers and context-switching | |
3 | * | |
4 | * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> | |
5 | * Copyright (C) 2008-2009 PetaLogix | |
6 | * Copyright (C) 2003 John Williams <jwilliams@itee.uq.edu.au> | |
7 | * Copyright (C) 2001,2002 NEC Corporation | |
8 | * Copyright (C) 2001,2002 Miles Bader <miles@gnu.org> | |
9 | * | |
10 | * This file is subject to the terms and conditions of the GNU General | |
11 | * Public License. See the file COPYING in the main directory of this | |
12 | * archive for more details. | |
13 | * | |
14 | * Written by Miles Bader <miles@gnu.org> | |
15 | * Heavily modified by John Williams for Microblaze | |
16 | */ | |
17 | ||
18 | #include <linux/sys.h> | |
19 | #include <linux/linkage.h> | |
20 | ||
21 | #include <asm/entry.h> | |
22 | #include <asm/current.h> | |
23 | #include <asm/processor.h> | |
24 | #include <asm/exceptions.h> | |
25 | #include <asm/asm-offsets.h> | |
26 | #include <asm/thread_info.h> | |
27 | ||
28 | #include <asm/page.h> | |
29 | #include <asm/unistd.h> | |
30 | ||
31 | #include <linux/errno.h> | |
32 | #include <asm/signal.h> | |
33 | ||
11d51360 MS |
34 | #undef DEBUG |
35 | ||
ca54502b MS |
36 | /* The size of a state save frame. */ |
37 | #define STATE_SAVE_SIZE (PT_SIZE + STATE_SAVE_ARG_SPACE) | |
38 | ||
39 | /* The offset of the struct pt_regs in a `state save frame' on the stack. */ | |
40 | #define PTO STATE_SAVE_ARG_SPACE /* 24 the space for args */ | |
41 | ||
42 | #define C_ENTRY(name) .globl name; .align 4; name | |
43 | ||
44 | /* | |
45 | * Various ways of setting and clearing BIP in flags reg. | |
46 | * This is mucky, but necessary using microblaze version that | |
47 | * allows msr ops to write to BIP | |
48 | */ | |
49 | #if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR | |
50 | .macro clear_bip | |
51 | msrclr r11, MSR_BIP | |
52 | nop | |
53 | .endm | |
54 | ||
55 | .macro set_bip | |
56 | msrset r11, MSR_BIP | |
57 | nop | |
58 | .endm | |
59 | ||
60 | .macro clear_eip | |
61 | msrclr r11, MSR_EIP | |
62 | nop | |
63 | .endm | |
64 | ||
65 | .macro set_ee | |
66 | msrset r11, MSR_EE | |
67 | nop | |
68 | .endm | |
69 | ||
70 | .macro disable_irq | |
71 | msrclr r11, MSR_IE | |
72 | nop | |
73 | .endm | |
74 | ||
75 | .macro enable_irq | |
76 | msrset r11, MSR_IE | |
77 | nop | |
78 | .endm | |
79 | ||
80 | .macro set_ums | |
81 | msrset r11, MSR_UMS | |
82 | nop | |
83 | msrclr r11, MSR_VMS | |
84 | nop | |
85 | .endm | |
86 | ||
87 | .macro set_vms | |
88 | msrclr r11, MSR_UMS | |
89 | nop | |
90 | msrset r11, MSR_VMS | |
91 | nop | |
92 | .endm | |
93 | ||
94 | .macro clear_vms_ums | |
3fbd93e5 | 95 | msrclr r11, MSR_VMS | MSR_UMS |
ca54502b MS |
96 | nop |
97 | .endm | |
98 | #else | |
99 | .macro clear_bip | |
100 | mfs r11, rmsr | |
101 | nop | |
102 | andi r11, r11, ~MSR_BIP | |
103 | mts rmsr, r11 | |
104 | nop | |
105 | .endm | |
106 | ||
107 | .macro set_bip | |
108 | mfs r11, rmsr | |
109 | nop | |
110 | ori r11, r11, MSR_BIP | |
111 | mts rmsr, r11 | |
112 | nop | |
113 | .endm | |
114 | ||
115 | .macro clear_eip | |
116 | mfs r11, rmsr | |
117 | nop | |
118 | andi r11, r11, ~MSR_EIP | |
119 | mts rmsr, r11 | |
120 | nop | |
121 | .endm | |
122 | ||
123 | .macro set_ee | |
124 | mfs r11, rmsr | |
125 | nop | |
126 | ori r11, r11, MSR_EE | |
127 | mts rmsr, r11 | |
128 | nop | |
129 | .endm | |
130 | ||
131 | .macro disable_irq | |
132 | mfs r11, rmsr | |
133 | nop | |
134 | andi r11, r11, ~MSR_IE | |
135 | mts rmsr, r11 | |
136 | nop | |
137 | .endm | |
138 | ||
139 | .macro enable_irq | |
140 | mfs r11, rmsr | |
141 | nop | |
142 | ori r11, r11, MSR_IE | |
143 | mts rmsr, r11 | |
144 | nop | |
145 | .endm | |
146 | ||
147 | .macro set_ums | |
148 | mfs r11, rmsr | |
149 | nop | |
150 | ori r11, r11, MSR_VMS | |
151 | andni r11, r11, MSR_UMS | |
152 | mts rmsr, r11 | |
153 | nop | |
154 | .endm | |
155 | ||
156 | .macro set_vms | |
157 | mfs r11, rmsr | |
158 | nop | |
159 | ori r11, r11, MSR_VMS | |
160 | andni r11, r11, MSR_UMS | |
161 | mts rmsr, r11 | |
162 | nop | |
163 | .endm | |
164 | ||
165 | .macro clear_vms_ums | |
166 | mfs r11, rmsr | |
167 | nop | |
168 | andni r11, r11, (MSR_VMS|MSR_UMS) | |
169 | mts rmsr,r11 | |
170 | nop | |
171 | .endm | |
172 | #endif | |
173 | ||
174 | /* Define how to call high-level functions. With MMU, virtual mode must be | |
175 | * enabled when calling the high-level function. Clobbers R11. | |
176 | * VM_ON, VM_OFF, DO_JUMP_BIPCLR, DO_CALL | |
177 | */ | |
178 | ||
179 | /* turn on virtual protected mode save */ | |
180 | #define VM_ON \ | |
a4a94dbf | 181 | set_ums; \ |
ca54502b | 182 | rted r0, 2f; \ |
a4a94dbf MS |
183 | nop; \ |
184 | 2: | |
ca54502b MS |
185 | |
186 | /* turn off virtual protected mode save and user mode save*/ | |
187 | #define VM_OFF \ | |
a4a94dbf | 188 | clear_vms_ums; \ |
ca54502b | 189 | rted r0, TOPHYS(1f); \ |
a4a94dbf MS |
190 | nop; \ |
191 | 1: | |
ca54502b MS |
192 | |
193 | #define SAVE_REGS \ | |
194 | swi r2, r1, PTO+PT_R2; /* Save SDA */ \ | |
36f60954 MS |
195 | swi r3, r1, PTO+PT_R3; \ |
196 | swi r4, r1, PTO+PT_R4; \ | |
ca54502b MS |
197 | swi r5, r1, PTO+PT_R5; \ |
198 | swi r6, r1, PTO+PT_R6; \ | |
199 | swi r7, r1, PTO+PT_R7; \ | |
200 | swi r8, r1, PTO+PT_R8; \ | |
201 | swi r9, r1, PTO+PT_R9; \ | |
202 | swi r10, r1, PTO+PT_R10; \ | |
203 | swi r11, r1, PTO+PT_R11; /* save clobbered regs after rval */\ | |
204 | swi r12, r1, PTO+PT_R12; \ | |
205 | swi r13, r1, PTO+PT_R13; /* Save SDA2 */ \ | |
206 | swi r14, r1, PTO+PT_PC; /* PC, before IRQ/trap */ \ | |
207 | swi r15, r1, PTO+PT_R15; /* Save LP */ \ | |
208 | swi r18, r1, PTO+PT_R18; /* Save asm scratch reg */ \ | |
209 | swi r19, r1, PTO+PT_R19; \ | |
210 | swi r20, r1, PTO+PT_R20; \ | |
211 | swi r21, r1, PTO+PT_R21; \ | |
212 | swi r22, r1, PTO+PT_R22; \ | |
213 | swi r23, r1, PTO+PT_R23; \ | |
214 | swi r24, r1, PTO+PT_R24; \ | |
215 | swi r25, r1, PTO+PT_R25; \ | |
216 | swi r26, r1, PTO+PT_R26; \ | |
217 | swi r27, r1, PTO+PT_R27; \ | |
218 | swi r28, r1, PTO+PT_R28; \ | |
219 | swi r29, r1, PTO+PT_R29; \ | |
220 | swi r30, r1, PTO+PT_R30; \ | |
221 | swi r31, r1, PTO+PT_R31; /* Save current task reg */ \ | |
222 | mfs r11, rmsr; /* save MSR */ \ | |
223 | nop; \ | |
224 | swi r11, r1, PTO+PT_MSR; | |
225 | ||
226 | #define RESTORE_REGS \ | |
227 | lwi r11, r1, PTO+PT_MSR; \ | |
228 | mts rmsr , r11; \ | |
229 | nop; \ | |
230 | lwi r2, r1, PTO+PT_R2; /* restore SDA */ \ | |
36f60954 MS |
231 | lwi r3, r1, PTO+PT_R3; \ |
232 | lwi r4, r1, PTO+PT_R4; \ | |
ca54502b MS |
233 | lwi r5, r1, PTO+PT_R5; \ |
234 | lwi r6, r1, PTO+PT_R6; \ | |
235 | lwi r7, r1, PTO+PT_R7; \ | |
236 | lwi r8, r1, PTO+PT_R8; \ | |
237 | lwi r9, r1, PTO+PT_R9; \ | |
238 | lwi r10, r1, PTO+PT_R10; \ | |
239 | lwi r11, r1, PTO+PT_R11; /* restore clobbered regs after rval */\ | |
240 | lwi r12, r1, PTO+PT_R12; \ | |
241 | lwi r13, r1, PTO+PT_R13; /* restore SDA2 */ \ | |
242 | lwi r14, r1, PTO+PT_PC; /* RESTORE_LINK PC, before IRQ/trap */\ | |
243 | lwi r15, r1, PTO+PT_R15; /* restore LP */ \ | |
244 | lwi r18, r1, PTO+PT_R18; /* restore asm scratch reg */ \ | |
245 | lwi r19, r1, PTO+PT_R19; \ | |
246 | lwi r20, r1, PTO+PT_R20; \ | |
247 | lwi r21, r1, PTO+PT_R21; \ | |
248 | lwi r22, r1, PTO+PT_R22; \ | |
249 | lwi r23, r1, PTO+PT_R23; \ | |
250 | lwi r24, r1, PTO+PT_R24; \ | |
251 | lwi r25, r1, PTO+PT_R25; \ | |
252 | lwi r26, r1, PTO+PT_R26; \ | |
253 | lwi r27, r1, PTO+PT_R27; \ | |
254 | lwi r28, r1, PTO+PT_R28; \ | |
255 | lwi r29, r1, PTO+PT_R29; \ | |
256 | lwi r30, r1, PTO+PT_R30; \ | |
257 | lwi r31, r1, PTO+PT_R31; /* Restore cur task reg */ | |
258 | ||
259 | .text | |
260 | ||
261 | /* | |
262 | * User trap. | |
263 | * | |
264 | * System calls are handled here. | |
265 | * | |
266 | * Syscall protocol: | |
267 | * Syscall number in r12, args in r5-r10 | |
268 | * Return value in r3 | |
269 | * | |
270 | * Trap entered via brki instruction, so BIP bit is set, and interrupts | |
271 | * are masked. This is nice, means we don't have to CLI before state save | |
272 | */ | |
273 | C_ENTRY(_user_exception): | |
274 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ | |
275 | addi r14, r14, 4 /* return address is 4 byte after call */ | |
276 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ | |
277 | ||
5c0d72b1 MS |
278 | mfs r11, rmsr |
279 | nop | |
280 | andi r11, r11, MSR_UMS | |
281 | bnei r11, 1f | |
282 | ||
283 | /* Kernel-mode state save - kernel execve */ | |
ca54502b MS |
284 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ |
285 | tophys(r1,r11); | |
286 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ | |
287 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
288 | ||
289 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
290 | SAVE_REGS | |
291 | ||
292 | addi r11, r0, 1; /* Was in kernel-mode. */ | |
293 | swi r11, r1, PTO+PT_MODE; /* pt_regs -> kernel mode */ | |
294 | brid 2f; | |
295 | nop; /* Fill delay slot */ | |
296 | ||
297 | /* User-mode state save. */ | |
298 | 1: | |
299 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
300 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ | |
301 | tophys(r1,r1); | |
302 | lwi r1, r1, TS_THREAD_INFO; /* get stack from task_struct */ | |
303 | /* calculate kernel stack pointer from task struct 8k */ | |
304 | addik r1, r1, THREAD_SIZE; | |
305 | tophys(r1,r1); | |
306 | ||
307 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
308 | SAVE_REGS | |
309 | ||
310 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ | |
311 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
312 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ | |
b1d70c62 | 313 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
ca54502b MS |
314 | /* Save away the syscall number. */ |
315 | swi r12, r1, PTO+PT_R0; | |
316 | tovirt(r1,r1) | |
317 | ||
ca54502b MS |
318 | /* where the trap should return need -8 to adjust for rtsd r15, 8*/ |
319 | /* Jump to the appropriate function for the system call number in r12 | |
320 | * (r12 is not preserved), or return an error if r12 is not valid. The LP | |
321 | * register should point to the location where | |
322 | * the called function should return. [note that MAKE_SYS_CALL uses label 1] */ | |
23575483 MS |
323 | |
324 | # Step into virtual mode. | |
325 | set_vms; | |
326 | addik r11, r0, 3f | |
327 | rtid r11, 0 | |
328 | nop | |
329 | 3: | |
b1d70c62 | 330 | lwi r11, CURRENT_TASK, TS_THREAD_INFO /* get thread info */ |
23575483 MS |
331 | lwi r11, r11, TI_FLAGS /* get flags in thread info */ |
332 | andi r11, r11, _TIF_WORK_SYSCALL_MASK | |
333 | beqi r11, 4f | |
334 | ||
335 | addik r3, r0, -ENOSYS | |
336 | swi r3, r1, PTO + PT_R3 | |
337 | brlid r15, do_syscall_trace_enter | |
338 | addik r5, r1, PTO + PT_R0 | |
339 | ||
340 | # do_syscall_trace_enter returns the new syscall nr. | |
341 | addk r12, r0, r3 | |
342 | lwi r5, r1, PTO+PT_R5; | |
343 | lwi r6, r1, PTO+PT_R6; | |
344 | lwi r7, r1, PTO+PT_R7; | |
345 | lwi r8, r1, PTO+PT_R8; | |
346 | lwi r9, r1, PTO+PT_R9; | |
347 | lwi r10, r1, PTO+PT_R10; | |
348 | 4: | |
349 | /* Jump to the appropriate function for the system call number in r12 | |
350 | * (r12 is not preserved), or return an error if r12 is not valid. | |
351 | * The LP register should point to the location where the called function | |
352 | * should return. [note that MAKE_SYS_CALL uses label 1] */ | |
353 | /* See if the system call number is valid */ | |
ca54502b | 354 | addi r11, r12, -__NR_syscalls; |
23575483 | 355 | bgei r11,5f; |
ca54502b MS |
356 | /* Figure out which function to use for this system call. */ |
357 | /* Note Microblaze barrel shift is optional, so don't rely on it */ | |
358 | add r12, r12, r12; /* convert num -> ptr */ | |
359 | add r12, r12, r12; | |
360 | ||
11d51360 | 361 | #ifdef DEBUG |
ca54502b | 362 | /* Trac syscalls and stored them to r0_ram */ |
23575483 | 363 | lwi r3, r12, 0x400 + r0_ram |
ca54502b | 364 | addi r3, r3, 1 |
23575483 | 365 | swi r3, r12, 0x400 + r0_ram |
11d51360 | 366 | #endif |
23575483 MS |
367 | |
368 | # Find and jump into the syscall handler. | |
369 | lwi r12, r12, sys_call_table | |
370 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
b9ea77e2 | 371 | addi r15, r0, ret_from_trap-8 |
23575483 | 372 | bra r12 |
ca54502b | 373 | |
ca54502b | 374 | /* The syscall number is invalid, return an error. */ |
23575483 | 375 | 5: |
ca54502b MS |
376 | addi r3, r0, -ENOSYS; |
377 | rtsd r15,8; /* looks like a normal subroutine return */ | |
378 | or r0, r0, r0 | |
379 | ||
380 | ||
23575483 | 381 | /* Entry point used to return from a syscall/trap */ |
ca54502b MS |
382 | /* We re-enable BIP bit before state restore */ |
383 | C_ENTRY(ret_from_trap): | |
b1d70c62 MS |
384 | swi r3, r1, PTO + PT_R3 |
385 | swi r4, r1, PTO + PT_R4 | |
386 | ||
36f60954 MS |
387 | lwi r11, r1, PTO+PT_MODE; |
388 | /* See if returning to kernel mode, if so, skip resched &c. */ | |
389 | bnei r11, 2f; | |
23575483 MS |
390 | /* We're returning to user mode, so check for various conditions that |
391 | * trigger rescheduling. */ | |
b1d70c62 MS |
392 | /* FIXME: Restructure all these flag checks. */ |
393 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ | |
23575483 MS |
394 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
395 | andi r11, r11, _TIF_WORK_SYSCALL_MASK | |
396 | beqi r11, 1f | |
397 | ||
23575483 MS |
398 | brlid r15, do_syscall_trace_leave |
399 | addik r5, r1, PTO + PT_R0 | |
23575483 | 400 | 1: |
ca54502b MS |
401 | /* We're returning to user mode, so check for various conditions that |
402 | * trigger rescheduling. */ | |
b1d70c62 MS |
403 | /* get thread info from current task */ |
404 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; | |
ca54502b MS |
405 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
406 | andi r11, r11, _TIF_NEED_RESCHED; | |
407 | beqi r11, 5f; | |
408 | ||
ca54502b MS |
409 | bralid r15, schedule; /* Call scheduler */ |
410 | nop; /* delay slot */ | |
ca54502b MS |
411 | |
412 | /* Maybe handle a signal */ | |
b1d70c62 MS |
413 | 5: /* get thread info from current task*/ |
414 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; | |
ca54502b MS |
415 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
416 | andi r11, r11, _TIF_SIGPENDING; | |
417 | beqi r11, 1f; /* Signals to handle, handle them */ | |
418 | ||
b9ea77e2 | 419 | addik r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
ca54502b MS |
420 | addi r7, r0, 1; /* Arg 3: int in_syscall */ |
421 | bralid r15, do_signal; /* Handle any signals */ | |
841d6e8c | 422 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
b1d70c62 MS |
423 | |
424 | /* Finally, return to user state. */ | |
96014cc3 | 425 | 1: set_bip; /* Ints masked for state restore */ |
8633bebc | 426 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
ca54502b MS |
427 | VM_OFF; |
428 | tophys(r1,r1); | |
429 | RESTORE_REGS; | |
430 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
431 | lwi r1, r1, PT_R1 - PT_SIZE;/* Restore user stack pointer. */ | |
432 | bri 6f; | |
433 | ||
434 | /* Return to kernel state. */ | |
96014cc3 MS |
435 | 2: set_bip; /* Ints masked for state restore */ |
436 | VM_OFF; | |
ca54502b MS |
437 | tophys(r1,r1); |
438 | RESTORE_REGS; | |
439 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
440 | tovirt(r1,r1); | |
441 | 6: | |
442 | TRAP_return: /* Make global symbol for debugging */ | |
443 | rtbd r14, 0; /* Instructions to return from an IRQ */ | |
444 | nop; | |
445 | ||
446 | ||
447 | /* These syscalls need access to the struct pt_regs on the stack, so we | |
448 | implement them in assembly (they're basically all wrappers anyway). */ | |
449 | ||
450 | C_ENTRY(sys_fork_wrapper): | |
451 | addi r5, r0, SIGCHLD /* Arg 0: flags */ | |
452 | lwi r6, r1, PTO+PT_R1 /* Arg 1: child SP (use parent's) */ | |
b9ea77e2 | 453 | addik r7, r1, PTO /* Arg 2: parent context */ |
ca54502b MS |
454 | add r8. r0, r0 /* Arg 3: (unused) */ |
455 | add r9, r0, r0; /* Arg 4: (unused) */ | |
456 | add r10, r0, r0; /* Arg 5: (unused) */ | |
457 | brid do_fork /* Do real work (tail-call) */ | |
458 | nop; | |
459 | ||
460 | /* This the initial entry point for a new child thread, with an appropriate | |
461 | stack in place that makes it look the the child is in the middle of an | |
462 | syscall. This function is actually `returned to' from switch_thread | |
463 | (copy_thread makes ret_from_fork the return address in each new thread's | |
464 | saved context). */ | |
465 | C_ENTRY(ret_from_fork): | |
466 | bralid r15, schedule_tail; /* ...which is schedule_tail's arg */ | |
467 | add r3, r5, r0; /* switch_thread returns the prev task */ | |
468 | /* ( in the delay slot ) */ | |
469 | add r3, r0, r0; /* Child's fork call should return 0. */ | |
470 | brid ret_from_trap; /* Do normal trap return */ | |
471 | nop; | |
472 | ||
e513588f AB |
473 | C_ENTRY(sys_vfork): |
474 | brid microblaze_vfork /* Do real work (tail-call) */ | |
b9ea77e2 | 475 | addik r5, r1, PTO |
ca54502b | 476 | |
e513588f | 477 | C_ENTRY(sys_clone): |
ca54502b | 478 | bnei r6, 1f; /* See if child SP arg (arg 1) is 0. */ |
570e3e23 | 479 | lwi r6, r1, PTO + PT_R1; /* If so, use paret's stack ptr */ |
b9ea77e2 MS |
480 | 1: addik r7, r1, PTO; /* Arg 2: parent context */ |
481 | add r8, r0, r0; /* Arg 3: (unused) */ | |
482 | add r9, r0, r0; /* Arg 4: (unused) */ | |
483 | add r10, r0, r0; /* Arg 5: (unused) */ | |
484 | brid do_fork /* Do real work (tail-call) */ | |
485 | nop; | |
ca54502b | 486 | |
e513588f | 487 | C_ENTRY(sys_execve): |
b9ea77e2 | 488 | addik r8, r1, PTO; /* add user context as 4th arg */ |
e513588f | 489 | brid microblaze_execve; /* Do real work (tail-call).*/ |
ca54502b MS |
490 | nop; |
491 | ||
ca54502b MS |
492 | C_ENTRY(sys_rt_sigreturn_wrapper): |
493 | swi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
494 | swi r4, r1, PTO+PT_R4; | |
b9ea77e2 | 495 | addik r5, r1, PTO; /* add user context as 1st arg */ |
ca54502b MS |
496 | brlid r15, sys_rt_sigreturn /* Do real work */ |
497 | nop; | |
498 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
499 | lwi r4, r1, PTO+PT_R4; | |
500 | bri ret_from_trap /* fall through will not work here due to align */ | |
501 | nop; | |
502 | ||
503 | /* | |
504 | * HW EXCEPTION rutine start | |
505 | */ | |
506 | ||
507 | #define SAVE_STATE \ | |
63708f63 | 508 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* save stack */ \ |
ca54502b | 509 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ \ |
ca54502b | 510 | /* See if already in kernel mode.*/ \ |
5c0d72b1 MS |
511 | mfs r11, rmsr; \ |
512 | nop; \ | |
513 | andi r11, r11, MSR_UMS; \ | |
514 | bnei r11, 1f; \ | |
ca54502b MS |
515 | /* Kernel-mode state save. */ \ |
516 | /* Reload kernel stack-ptr. */ \ | |
517 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ | |
518 | tophys(r1,r11); \ | |
519 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ \ | |
520 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ | |
521 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ | |
ca54502b MS |
522 | SAVE_REGS \ |
523 | /* PC, before IRQ/trap - this is one instruction above */ \ | |
524 | swi r17, r1, PTO+PT_PC; \ | |
525 | \ | |
526 | addi r11, r0, 1; /* Was in kernel-mode. */ \ | |
527 | swi r11, r1, PTO+PT_MODE; \ | |
528 | brid 2f; \ | |
529 | nop; /* Fill delay slot */ \ | |
530 | 1: /* User-mode state save. */ \ | |
531 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ | |
532 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\ | |
533 | tophys(r1,r1); \ | |
534 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ \ | |
535 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */\ | |
536 | tophys(r1,r1); \ | |
537 | \ | |
538 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ | |
ca54502b MS |
539 | SAVE_REGS \ |
540 | /* PC, before IRQ/trap - this is one instruction above FIXME*/ \ | |
541 | swi r17, r1, PTO+PT_PC; \ | |
542 | \ | |
543 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ \ | |
544 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ | |
545 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ \ | |
b1d70c62 | 546 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); \ |
ca54502b MS |
547 | /* Save away the syscall number. */ \ |
548 | swi r0, r1, PTO+PT_R0; \ | |
549 | tovirt(r1,r1) | |
550 | ||
551 | C_ENTRY(full_exception_trap): | |
ca54502b MS |
552 | /* adjust exception address for privileged instruction |
553 | * for finding where is it */ | |
554 | addik r17, r17, -4 | |
555 | SAVE_STATE /* Save registers */ | |
556 | /* FIXME this can be store directly in PT_ESR reg. | |
557 | * I tested it but there is a fault */ | |
558 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
b9ea77e2 MS |
559 | addik r15, r0, ret_from_exc - 8 |
560 | addik r5, r1, PTO /* parameter struct pt_regs * regs */ | |
ca54502b MS |
561 | mfs r6, resr |
562 | nop | |
563 | mfs r7, rfsr; /* save FSR */ | |
564 | nop | |
131e4e97 MS |
565 | mts rfsr, r0; /* Clear sticky fsr */ |
566 | nop | |
b9ea77e2 | 567 | addik r12, r0, full_exception |
ca54502b | 568 | set_vms; |
8b110d15 | 569 | rted r12, 0; |
ca54502b MS |
570 | nop; |
571 | ||
572 | /* | |
573 | * Unaligned data trap. | |
574 | * | |
575 | * Unaligned data trap last on 4k page is handled here. | |
576 | * | |
577 | * Trap entered via exception, so EE bit is set, and interrupts | |
578 | * are masked. This is nice, means we don't have to CLI before state save | |
579 | * | |
580 | * The assembler routine is in "arch/microblaze/kernel/hw_exception_handler.S" | |
581 | */ | |
582 | C_ENTRY(unaligned_data_trap): | |
8b110d15 MS |
583 | /* MS: I have to save r11 value and then restore it because |
584 | * set_bit, clear_eip, set_ee use r11 as temp register if MSR | |
585 | * instructions are not used. We don't need to do if MSR instructions | |
586 | * are used and they use r0 instead of r11. | |
587 | * I am using ENTRY_SP which should be primary used only for stack | |
588 | * pointer saving. */ | |
589 | swi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
590 | set_bip; /* equalize initial state for all possible entries */ | |
591 | clear_eip; | |
592 | set_ee; | |
593 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
ca54502b MS |
594 | SAVE_STATE /* Save registers.*/ |
595 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
b9ea77e2 | 596 | addik r15, r0, ret_from_exc-8 |
ca54502b MS |
597 | mfs r3, resr /* ESR */ |
598 | nop | |
599 | mfs r4, rear /* EAR */ | |
600 | nop | |
b9ea77e2 MS |
601 | addik r7, r1, PTO /* parameter struct pt_regs * regs */ |
602 | addik r12, r0, _unaligned_data_exception | |
ca54502b MS |
603 | set_vms; |
604 | rtbd r12, 0; /* interrupts enabled */ | |
605 | nop; | |
606 | ||
607 | /* | |
608 | * Page fault traps. | |
609 | * | |
610 | * If the real exception handler (from hw_exception_handler.S) didn't find | |
611 | * the mapping for the process, then we're thrown here to handle such situation. | |
612 | * | |
613 | * Trap entered via exceptions, so EE bit is set, and interrupts | |
614 | * are masked. This is nice, means we don't have to CLI before state save | |
615 | * | |
616 | * Build a standard exception frame for TLB Access errors. All TLB exceptions | |
617 | * will bail out to this point if they can't resolve the lightweight TLB fault. | |
618 | * | |
619 | * The C function called is in "arch/microblaze/mm/fault.c", declared as: | |
620 | * void do_page_fault(struct pt_regs *regs, | |
621 | * unsigned long address, | |
622 | * unsigned long error_code) | |
623 | */ | |
624 | /* data and intruction trap - which is choose is resolved int fault.c */ | |
625 | C_ENTRY(page_fault_data_trap): | |
ca54502b MS |
626 | SAVE_STATE /* Save registers.*/ |
627 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
b9ea77e2 MS |
628 | addik r15, r0, ret_from_exc-8 |
629 | addik r5, r1, PTO /* parameter struct pt_regs * regs */ | |
ca54502b MS |
630 | mfs r6, rear /* parameter unsigned long address */ |
631 | nop | |
632 | mfs r7, resr /* parameter unsigned long error_code */ | |
633 | nop | |
b9ea77e2 | 634 | addik r12, r0, do_page_fault |
ca54502b | 635 | set_vms; |
8b110d15 | 636 | rted r12, 0; /* interrupts enabled */ |
ca54502b MS |
637 | nop; |
638 | ||
639 | C_ENTRY(page_fault_instr_trap): | |
ca54502b MS |
640 | SAVE_STATE /* Save registers.*/ |
641 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
b9ea77e2 MS |
642 | addik r15, r0, ret_from_exc-8 |
643 | addik r5, r1, PTO /* parameter struct pt_regs * regs */ | |
ca54502b MS |
644 | mfs r6, rear /* parameter unsigned long address */ |
645 | nop | |
646 | ori r7, r0, 0 /* parameter unsigned long error_code */ | |
b9ea77e2 | 647 | addik r12, r0, do_page_fault |
ca54502b | 648 | set_vms; |
8b110d15 | 649 | rted r12, 0; /* interrupts enabled */ |
ca54502b MS |
650 | nop; |
651 | ||
652 | /* Entry point used to return from an exception. */ | |
653 | C_ENTRY(ret_from_exc): | |
ca54502b MS |
654 | lwi r11, r1, PTO+PT_MODE; |
655 | bnei r11, 2f; /* See if returning to kernel mode, */ | |
656 | /* ... if so, skip resched &c. */ | |
657 | ||
658 | /* We're returning to user mode, so check for various conditions that | |
659 | trigger rescheduling. */ | |
b1d70c62 | 660 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
ca54502b MS |
661 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
662 | andi r11, r11, _TIF_NEED_RESCHED; | |
663 | beqi r11, 5f; | |
664 | ||
665 | /* Call the scheduler before returning from a syscall/trap. */ | |
666 | bralid r15, schedule; /* Call scheduler */ | |
667 | nop; /* delay slot */ | |
668 | ||
669 | /* Maybe handle a signal */ | |
b1d70c62 | 670 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
ca54502b MS |
671 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
672 | andi r11, r11, _TIF_SIGPENDING; | |
673 | beqi r11, 1f; /* Signals to handle, handle them */ | |
674 | ||
675 | /* | |
676 | * Handle a signal return; Pending signals should be in r18. | |
677 | * | |
678 | * Not all registers are saved by the normal trap/interrupt entry | |
679 | * points (for instance, call-saved registers (because the normal | |
680 | * C-compiler calling sequence in the kernel makes sure they're | |
681 | * preserved), and call-clobbered registers in the case of | |
682 | * traps), but signal handlers may want to examine or change the | |
683 | * complete register state. Here we save anything not saved by | |
684 | * the normal entry sequence, so that it may be safely restored | |
36f60954 | 685 | * (in a possibly modified form) after do_signal returns. */ |
b9ea77e2 | 686 | addik r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
ca54502b MS |
687 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
688 | bralid r15, do_signal; /* Handle any signals */ | |
841d6e8c | 689 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
ca54502b MS |
690 | |
691 | /* Finally, return to user state. */ | |
96014cc3 | 692 | 1: set_bip; /* Ints masked for state restore */ |
8633bebc | 693 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
ca54502b MS |
694 | VM_OFF; |
695 | tophys(r1,r1); | |
696 | ||
ca54502b MS |
697 | RESTORE_REGS; |
698 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
699 | ||
700 | lwi r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer. */ | |
701 | bri 6f; | |
702 | /* Return to kernel state. */ | |
96014cc3 MS |
703 | 2: set_bip; /* Ints masked for state restore */ |
704 | VM_OFF; | |
ca54502b | 705 | tophys(r1,r1); |
ca54502b MS |
706 | RESTORE_REGS; |
707 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
708 | ||
709 | tovirt(r1,r1); | |
710 | 6: | |
711 | EXC_return: /* Make global symbol for debugging */ | |
712 | rtbd r14, 0; /* Instructions to return from an IRQ */ | |
713 | nop; | |
714 | ||
715 | /* | |
716 | * HW EXCEPTION rutine end | |
717 | */ | |
718 | ||
719 | /* | |
720 | * Hardware maskable interrupts. | |
721 | * | |
722 | * The stack-pointer (r1) should have already been saved to the memory | |
723 | * location PER_CPU(ENTRY_SP). | |
724 | */ | |
725 | C_ENTRY(_interrupt): | |
726 | /* MS: we are in physical address */ | |
727 | /* Save registers, switch to proper stack, convert SP to virtual.*/ | |
728 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) | |
729 | swi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); | |
730 | /* MS: See if already in kernel mode. */ | |
5c0d72b1 MS |
731 | mfs r11, rmsr |
732 | nop | |
733 | andi r11, r11, MSR_UMS | |
734 | bnei r11, 1f | |
ca54502b MS |
735 | |
736 | /* Kernel-mode state save. */ | |
737 | or r11, r1, r0 | |
738 | tophys(r1,r11); /* MS: I have in r1 physical address where stack is */ | |
739 | /* MS: Save original SP - position PT_R1 to next stack frame 4 *1 - 152*/ | |
740 | swi r11, r1, (PT_R1 - PT_SIZE); | |
741 | /* MS: restore r11 because of saving in SAVE_REGS */ | |
742 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); | |
743 | /* save registers */ | |
744 | /* MS: Make room on the stack -> activation record */ | |
745 | addik r1, r1, -STATE_SAVE_SIZE; | |
ca54502b MS |
746 | SAVE_REGS |
747 | /* MS: store mode */ | |
748 | addi r11, r0, 1; /* MS: Was in kernel-mode. */ | |
749 | swi r11, r1, PTO + PT_MODE; /* MS: and save it */ | |
750 | brid 2f; | |
751 | nop; /* MS: Fill delay slot */ | |
752 | ||
753 | 1: | |
754 | /* User-mode state save. */ | |
755 | /* MS: restore r11 -> FIXME move before SAVE_REG */ | |
756 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); | |
757 | /* MS: get the saved current */ | |
758 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); | |
759 | tophys(r1,r1); | |
760 | lwi r1, r1, TS_THREAD_INFO; | |
761 | addik r1, r1, THREAD_SIZE; | |
762 | tophys(r1,r1); | |
763 | /* save registers */ | |
764 | addik r1, r1, -STATE_SAVE_SIZE; | |
ca54502b MS |
765 | SAVE_REGS |
766 | /* calculate mode */ | |
767 | swi r0, r1, PTO + PT_MODE; | |
768 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
769 | swi r11, r1, PTO+PT_R1; | |
ca54502b | 770 | 2: |
b1d70c62 | 771 | lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
ca54502b MS |
772 | swi r0, r1, PTO + PT_R0; |
773 | tovirt(r1,r1) | |
b9ea77e2 | 774 | addik r5, r1, PTO; |
ca54502b | 775 | set_vms; |
b9ea77e2 MS |
776 | addik r11, r0, do_IRQ; |
777 | addik r15, r0, irq_call; | |
ca54502b MS |
778 | irq_call:rtbd r11, 0; |
779 | nop; | |
780 | ||
781 | /* MS: we are in virtual mode */ | |
782 | ret_from_irq: | |
783 | lwi r11, r1, PTO + PT_MODE; | |
784 | bnei r11, 2f; | |
785 | ||
b1d70c62 | 786 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
ca54502b MS |
787 | lwi r11, r11, TI_FLAGS; /* MS: get flags from thread info */ |
788 | andi r11, r11, _TIF_NEED_RESCHED; | |
789 | beqi r11, 5f | |
790 | bralid r15, schedule; | |
791 | nop; /* delay slot */ | |
792 | ||
793 | /* Maybe handle a signal */ | |
b1d70c62 | 794 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* MS: get thread info */ |
ca54502b MS |
795 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
796 | andi r11, r11, _TIF_SIGPENDING; | |
797 | beqid r11, no_intr_resched | |
798 | /* Handle a signal return; Pending signals should be in r18. */ | |
799 | addi r7, r0, 0; /* Arg 3: int in_syscall */ | |
b9ea77e2 | 800 | addik r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
ca54502b MS |
801 | bralid r15, do_signal; /* Handle any signals */ |
802 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ | |
803 | ||
804 | /* Finally, return to user state. */ | |
805 | no_intr_resched: | |
806 | /* Disable interrupts, we are now committed to the state restore */ | |
807 | disable_irq | |
8633bebc | 808 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); |
ca54502b MS |
809 | VM_OFF; |
810 | tophys(r1,r1); | |
ca54502b MS |
811 | RESTORE_REGS |
812 | addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */ | |
813 | lwi r1, r1, PT_R1 - PT_SIZE; | |
814 | bri 6f; | |
815 | /* MS: Return to kernel state. */ | |
77753790 MS |
816 | 2: |
817 | #ifdef CONFIG_PREEMPT | |
b1d70c62 | 818 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
77753790 MS |
819 | /* MS: get preempt_count from thread info */ |
820 | lwi r5, r11, TI_PREEMPT_COUNT; | |
821 | bgti r5, restore; | |
822 | ||
823 | lwi r5, r11, TI_FLAGS; /* get flags in thread info */ | |
824 | andi r5, r5, _TIF_NEED_RESCHED; | |
825 | beqi r5, restore /* if zero jump over */ | |
826 | ||
827 | preempt: | |
828 | /* interrupts are off that's why I am calling preempt_chedule_irq */ | |
829 | bralid r15, preempt_schedule_irq | |
830 | nop | |
b1d70c62 | 831 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
77753790 MS |
832 | lwi r5, r11, TI_FLAGS; /* get flags in thread info */ |
833 | andi r5, r5, _TIF_NEED_RESCHED; | |
834 | bnei r5, preempt /* if non zero jump to resched */ | |
835 | restore: | |
836 | #endif | |
837 | VM_OFF /* MS: turn off MMU */ | |
ca54502b | 838 | tophys(r1,r1) |
ca54502b MS |
839 | RESTORE_REGS |
840 | addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */ | |
841 | tovirt(r1,r1); | |
842 | 6: | |
843 | IRQ_return: /* MS: Make global symbol for debugging */ | |
844 | rtid r14, 0 | |
845 | nop | |
846 | ||
847 | /* | |
848 | * `Debug' trap | |
849 | * We enter dbtrap in "BIP" (breakpoint) mode. | |
850 | * So we exit the breakpoint mode with an 'rtbd' and proceed with the | |
851 | * original dbtrap. | |
852 | * however, wait to save state first | |
853 | */ | |
854 | C_ENTRY(_debug_exception): | |
855 | /* BIP bit is set on entry, no interrupts can occur */ | |
856 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) | |
857 | ||
858 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ | |
859 | set_bip; /*equalize initial state for all possible entries*/ | |
860 | clear_eip; | |
861 | enable_irq; | |
5c0d72b1 MS |
862 | mfs r11, rmsr |
863 | nop | |
864 | andi r11, r11, MSR_UMS | |
865 | bnei r11, 1f | |
ca54502b MS |
866 | /* Kernel-mode state save. */ |
867 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ | |
868 | tophys(r1,r11); | |
869 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ | |
870 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
871 | ||
872 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
ca54502b MS |
873 | SAVE_REGS; |
874 | ||
875 | addi r11, r0, 1; /* Was in kernel-mode. */ | |
876 | swi r11, r1, PTO + PT_MODE; | |
877 | brid 2f; | |
878 | nop; /* Fill delay slot */ | |
879 | 1: /* User-mode state save. */ | |
880 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
881 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ | |
882 | tophys(r1,r1); | |
883 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ | |
884 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */ | |
885 | tophys(r1,r1); | |
886 | ||
887 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
ca54502b MS |
888 | SAVE_REGS; |
889 | ||
890 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ | |
891 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
892 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ | |
b1d70c62 | 893 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
ca54502b MS |
894 | /* Save away the syscall number. */ |
895 | swi r0, r1, PTO+PT_R0; | |
896 | tovirt(r1,r1) | |
897 | ||
898 | addi r5, r0, SIGTRAP /* send the trap signal */ | |
899 | add r6, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
900 | addk r7, r0, r0 /* 3rd param zero */ | |
901 | ||
902 | set_vms; | |
b9ea77e2 MS |
903 | addik r11, r0, send_sig; |
904 | addik r15, r0, dbtrap_call; | |
ca54502b MS |
905 | dbtrap_call: rtbd r11, 0; |
906 | nop; | |
907 | ||
908 | set_bip; /* Ints masked for state restore*/ | |
909 | lwi r11, r1, PTO+PT_MODE; | |
910 | bnei r11, 2f; | |
911 | ||
912 | /* Get current task ptr into r11 */ | |
b1d70c62 | 913 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
ca54502b MS |
914 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
915 | andi r11, r11, _TIF_NEED_RESCHED; | |
916 | beqi r11, 5f; | |
917 | ||
918 | /* Call the scheduler before returning from a syscall/trap. */ | |
919 | ||
920 | bralid r15, schedule; /* Call scheduler */ | |
921 | nop; /* delay slot */ | |
922 | /* XXX Is PT_DTRACE handling needed here? */ | |
923 | /* XXX m68knommu also checks TASK_STATE & TASK_COUNTER here. */ | |
924 | ||
925 | /* Maybe handle a signal */ | |
b1d70c62 | 926 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
ca54502b MS |
927 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
928 | andi r11, r11, _TIF_SIGPENDING; | |
929 | beqi r11, 1f; /* Signals to handle, handle them */ | |
930 | ||
931 | /* Handle a signal return; Pending signals should be in r18. */ | |
932 | /* Not all registers are saved by the normal trap/interrupt entry | |
933 | points (for instance, call-saved registers (because the normal | |
934 | C-compiler calling sequence in the kernel makes sure they're | |
935 | preserved), and call-clobbered registers in the case of | |
936 | traps), but signal handlers may want to examine or change the | |
937 | complete register state. Here we save anything not saved by | |
938 | the normal entry sequence, so that it may be safely restored | |
939 | (in a possibly modified form) after do_signal returns. */ | |
940 | ||
b9ea77e2 | 941 | addik r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
ca54502b MS |
942 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
943 | bralid r15, do_signal; /* Handle any signals */ | |
841d6e8c | 944 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
ca54502b MS |
945 | |
946 | ||
947 | /* Finally, return to user state. */ | |
5c0d72b1 | 948 | 1: |
8633bebc | 949 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
ca54502b MS |
950 | VM_OFF; |
951 | tophys(r1,r1); | |
952 | ||
ca54502b MS |
953 | RESTORE_REGS |
954 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
955 | ||
956 | ||
957 | lwi r1, r1, PT_R1 - PT_SIZE; | |
958 | /* Restore user stack pointer. */ | |
959 | bri 6f; | |
960 | ||
961 | /* Return to kernel state. */ | |
962 | 2: VM_OFF; | |
963 | tophys(r1,r1); | |
ca54502b MS |
964 | RESTORE_REGS |
965 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
966 | ||
967 | tovirt(r1,r1); | |
968 | 6: | |
969 | DBTRAP_return: /* Make global symbol for debugging */ | |
970 | rtbd r14, 0; /* Instructions to return from an IRQ */ | |
971 | nop; | |
972 | ||
973 | ||
974 | ||
975 | ENTRY(_switch_to) | |
976 | /* prepare return value */ | |
b1d70c62 | 977 | addk r3, r0, CURRENT_TASK |
ca54502b MS |
978 | |
979 | /* save registers in cpu_context */ | |
980 | /* use r11 and r12, volatile registers, as temp register */ | |
981 | /* give start of cpu_context for previous process */ | |
982 | addik r11, r5, TI_CPU_CONTEXT | |
983 | swi r1, r11, CC_R1 | |
984 | swi r2, r11, CC_R2 | |
985 | /* skip volatile registers. | |
986 | * they are saved on stack when we jumped to _switch_to() */ | |
987 | /* dedicated registers */ | |
988 | swi r13, r11, CC_R13 | |
989 | swi r14, r11, CC_R14 | |
990 | swi r15, r11, CC_R15 | |
991 | swi r16, r11, CC_R16 | |
992 | swi r17, r11, CC_R17 | |
993 | swi r18, r11, CC_R18 | |
994 | /* save non-volatile registers */ | |
995 | swi r19, r11, CC_R19 | |
996 | swi r20, r11, CC_R20 | |
997 | swi r21, r11, CC_R21 | |
998 | swi r22, r11, CC_R22 | |
999 | swi r23, r11, CC_R23 | |
1000 | swi r24, r11, CC_R24 | |
1001 | swi r25, r11, CC_R25 | |
1002 | swi r26, r11, CC_R26 | |
1003 | swi r27, r11, CC_R27 | |
1004 | swi r28, r11, CC_R28 | |
1005 | swi r29, r11, CC_R29 | |
1006 | swi r30, r11, CC_R30 | |
1007 | /* special purpose registers */ | |
1008 | mfs r12, rmsr | |
1009 | nop | |
1010 | swi r12, r11, CC_MSR | |
1011 | mfs r12, rear | |
1012 | nop | |
1013 | swi r12, r11, CC_EAR | |
1014 | mfs r12, resr | |
1015 | nop | |
1016 | swi r12, r11, CC_ESR | |
1017 | mfs r12, rfsr | |
1018 | nop | |
1019 | swi r12, r11, CC_FSR | |
1020 | ||
b1d70c62 MS |
1021 | /* update r31, the current-give me pointer to task which will be next */ |
1022 | lwi CURRENT_TASK, r6, TI_TASK | |
ca54502b | 1023 | /* stored it to current_save too */ |
b1d70c62 | 1024 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE) |
ca54502b MS |
1025 | |
1026 | /* get new process' cpu context and restore */ | |
1027 | /* give me start where start context of next task */ | |
1028 | addik r11, r6, TI_CPU_CONTEXT | |
1029 | ||
1030 | /* non-volatile registers */ | |
1031 | lwi r30, r11, CC_R30 | |
1032 | lwi r29, r11, CC_R29 | |
1033 | lwi r28, r11, CC_R28 | |
1034 | lwi r27, r11, CC_R27 | |
1035 | lwi r26, r11, CC_R26 | |
1036 | lwi r25, r11, CC_R25 | |
1037 | lwi r24, r11, CC_R24 | |
1038 | lwi r23, r11, CC_R23 | |
1039 | lwi r22, r11, CC_R22 | |
1040 | lwi r21, r11, CC_R21 | |
1041 | lwi r20, r11, CC_R20 | |
1042 | lwi r19, r11, CC_R19 | |
1043 | /* dedicated registers */ | |
1044 | lwi r18, r11, CC_R18 | |
1045 | lwi r17, r11, CC_R17 | |
1046 | lwi r16, r11, CC_R16 | |
1047 | lwi r15, r11, CC_R15 | |
1048 | lwi r14, r11, CC_R14 | |
1049 | lwi r13, r11, CC_R13 | |
1050 | /* skip volatile registers */ | |
1051 | lwi r2, r11, CC_R2 | |
1052 | lwi r1, r11, CC_R1 | |
1053 | ||
1054 | /* special purpose registers */ | |
1055 | lwi r12, r11, CC_FSR | |
1056 | mts rfsr, r12 | |
1057 | nop | |
1058 | lwi r12, r11, CC_MSR | |
1059 | mts rmsr, r12 | |
1060 | nop | |
1061 | ||
1062 | rtsd r15, 8 | |
1063 | nop | |
1064 | ||
1065 | ENTRY(_reset) | |
1066 | brai 0x70; /* Jump back to FS-boot */ | |
1067 | ||
1068 | ENTRY(_break) | |
1069 | mfs r5, rmsr | |
1070 | nop | |
1071 | swi r5, r0, 0x250 + TOPHYS(r0_ram) | |
1072 | mfs r5, resr | |
1073 | nop | |
1074 | swi r5, r0, 0x254 + TOPHYS(r0_ram) | |
1075 | bri 0 | |
1076 | ||
1077 | /* These are compiled and loaded into high memory, then | |
1078 | * copied into place in mach_early_setup */ | |
1079 | .section .init.ivt, "ax" | |
1080 | .org 0x0 | |
1081 | /* this is very important - here is the reset vector */ | |
1082 | /* in current MMU branch you don't care what is here - it is | |
1083 | * used from bootloader site - but this is correct for FS-BOOT */ | |
1084 | brai 0x70 | |
1085 | nop | |
1086 | brai TOPHYS(_user_exception); /* syscall handler */ | |
1087 | brai TOPHYS(_interrupt); /* Interrupt handler */ | |
1088 | brai TOPHYS(_break); /* nmi trap handler */ | |
1089 | brai TOPHYS(_hw_exception_handler); /* HW exception handler */ | |
1090 | ||
1091 | .org 0x60 | |
1092 | brai TOPHYS(_debug_exception); /* debug trap handler*/ | |
1093 | ||
1094 | .section .rodata,"a" | |
1095 | #include "syscall_table.S" | |
1096 | ||
1097 | syscall_table_size=(.-sys_call_table) | |
1098 | ||
ce3266c0 SM |
1099 | type_SYSCALL: |
1100 | .ascii "SYSCALL\0" | |
1101 | type_IRQ: | |
1102 | .ascii "IRQ\0" | |
1103 | type_IRQ_PREEMPT: | |
1104 | .ascii "IRQ (PREEMPTED)\0" | |
1105 | type_SYSCALL_PREEMPT: | |
1106 | .ascii " SYSCALL (PREEMPTED)\0" | |
1107 | ||
1108 | /* | |
1109 | * Trap decoding for stack unwinder | |
1110 | * Tuples are (start addr, end addr, string) | |
1111 | * If return address lies on [start addr, end addr], | |
1112 | * unwinder displays 'string' | |
1113 | */ | |
1114 | ||
1115 | .align 4 | |
1116 | .global microblaze_trap_handlers | |
1117 | microblaze_trap_handlers: | |
1118 | /* Exact matches come first */ | |
1119 | .word ret_from_trap; .word ret_from_trap ; .word type_SYSCALL | |
1120 | .word ret_from_irq ; .word ret_from_irq ; .word type_IRQ | |
1121 | /* Fuzzy matches go here */ | |
1122 | .word ret_from_irq ; .word no_intr_resched ; .word type_IRQ_PREEMPT | |
1123 | .word ret_from_trap; .word TRAP_return ; .word type_SYSCALL_PREEMPT | |
1124 | /* End of table */ | |
1125 | .word 0 ; .word 0 ; .word 0 |