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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 | ||
34 | /* The size of a state save frame. */ | |
35 | #define STATE_SAVE_SIZE (PT_SIZE + STATE_SAVE_ARG_SPACE) | |
36 | ||
37 | /* The offset of the struct pt_regs in a `state save frame' on the stack. */ | |
38 | #define PTO STATE_SAVE_ARG_SPACE /* 24 the space for args */ | |
39 | ||
40 | #define C_ENTRY(name) .globl name; .align 4; name | |
41 | ||
42 | /* | |
43 | * Various ways of setting and clearing BIP in flags reg. | |
44 | * This is mucky, but necessary using microblaze version that | |
45 | * allows msr ops to write to BIP | |
46 | */ | |
47 | #if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR | |
48 | .macro clear_bip | |
49 | msrclr r11, MSR_BIP | |
50 | nop | |
51 | .endm | |
52 | ||
53 | .macro set_bip | |
54 | msrset r11, MSR_BIP | |
55 | nop | |
56 | .endm | |
57 | ||
58 | .macro clear_eip | |
59 | msrclr r11, MSR_EIP | |
60 | nop | |
61 | .endm | |
62 | ||
63 | .macro set_ee | |
64 | msrset r11, MSR_EE | |
65 | nop | |
66 | .endm | |
67 | ||
68 | .macro disable_irq | |
69 | msrclr r11, MSR_IE | |
70 | nop | |
71 | .endm | |
72 | ||
73 | .macro enable_irq | |
74 | msrset r11, MSR_IE | |
75 | nop | |
76 | .endm | |
77 | ||
78 | .macro set_ums | |
79 | msrset r11, MSR_UMS | |
80 | nop | |
81 | msrclr r11, MSR_VMS | |
82 | nop | |
83 | .endm | |
84 | ||
85 | .macro set_vms | |
86 | msrclr r11, MSR_UMS | |
87 | nop | |
88 | msrset r11, MSR_VMS | |
89 | nop | |
90 | .endm | |
91 | ||
92 | .macro clear_vms_ums | |
93 | msrclr r11, MSR_VMS | |
94 | nop | |
95 | msrclr r11, MSR_UMS | |
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 \ | |
181 | set_ums; \ | |
182 | rted r0, 2f; \ | |
183 | 2: nop; | |
184 | ||
185 | /* turn off virtual protected mode save and user mode save*/ | |
186 | #define VM_OFF \ | |
187 | clear_vms_ums; \ | |
188 | rted r0, TOPHYS(1f); \ | |
189 | 1: nop; | |
190 | ||
191 | #define SAVE_REGS \ | |
192 | swi r2, r1, PTO+PT_R2; /* Save SDA */ \ | |
193 | swi r5, r1, PTO+PT_R5; \ | |
194 | swi r6, r1, PTO+PT_R6; \ | |
195 | swi r7, r1, PTO+PT_R7; \ | |
196 | swi r8, r1, PTO+PT_R8; \ | |
197 | swi r9, r1, PTO+PT_R9; \ | |
198 | swi r10, r1, PTO+PT_R10; \ | |
199 | swi r11, r1, PTO+PT_R11; /* save clobbered regs after rval */\ | |
200 | swi r12, r1, PTO+PT_R12; \ | |
201 | swi r13, r1, PTO+PT_R13; /* Save SDA2 */ \ | |
202 | swi r14, r1, PTO+PT_PC; /* PC, before IRQ/trap */ \ | |
203 | swi r15, r1, PTO+PT_R15; /* Save LP */ \ | |
204 | swi r18, r1, PTO+PT_R18; /* Save asm scratch reg */ \ | |
205 | swi r19, r1, PTO+PT_R19; \ | |
206 | swi r20, r1, PTO+PT_R20; \ | |
207 | swi r21, r1, PTO+PT_R21; \ | |
208 | swi r22, r1, PTO+PT_R22; \ | |
209 | swi r23, r1, PTO+PT_R23; \ | |
210 | swi r24, r1, PTO+PT_R24; \ | |
211 | swi r25, r1, PTO+PT_R25; \ | |
212 | swi r26, r1, PTO+PT_R26; \ | |
213 | swi r27, r1, PTO+PT_R27; \ | |
214 | swi r28, r1, PTO+PT_R28; \ | |
215 | swi r29, r1, PTO+PT_R29; \ | |
216 | swi r30, r1, PTO+PT_R30; \ | |
217 | swi r31, r1, PTO+PT_R31; /* Save current task reg */ \ | |
218 | mfs r11, rmsr; /* save MSR */ \ | |
219 | nop; \ | |
220 | swi r11, r1, PTO+PT_MSR; | |
221 | ||
222 | #define RESTORE_REGS \ | |
223 | lwi r11, r1, PTO+PT_MSR; \ | |
224 | mts rmsr , r11; \ | |
225 | nop; \ | |
226 | lwi r2, r1, PTO+PT_R2; /* restore SDA */ \ | |
227 | lwi r5, r1, PTO+PT_R5; \ | |
228 | lwi r6, r1, PTO+PT_R6; \ | |
229 | lwi r7, r1, PTO+PT_R7; \ | |
230 | lwi r8, r1, PTO+PT_R8; \ | |
231 | lwi r9, r1, PTO+PT_R9; \ | |
232 | lwi r10, r1, PTO+PT_R10; \ | |
233 | lwi r11, r1, PTO+PT_R11; /* restore clobbered regs after rval */\ | |
234 | lwi r12, r1, PTO+PT_R12; \ | |
235 | lwi r13, r1, PTO+PT_R13; /* restore SDA2 */ \ | |
236 | lwi r14, r1, PTO+PT_PC; /* RESTORE_LINK PC, before IRQ/trap */\ | |
237 | lwi r15, r1, PTO+PT_R15; /* restore LP */ \ | |
238 | lwi r18, r1, PTO+PT_R18; /* restore asm scratch reg */ \ | |
239 | lwi r19, r1, PTO+PT_R19; \ | |
240 | lwi r20, r1, PTO+PT_R20; \ | |
241 | lwi r21, r1, PTO+PT_R21; \ | |
242 | lwi r22, r1, PTO+PT_R22; \ | |
243 | lwi r23, r1, PTO+PT_R23; \ | |
244 | lwi r24, r1, PTO+PT_R24; \ | |
245 | lwi r25, r1, PTO+PT_R25; \ | |
246 | lwi r26, r1, PTO+PT_R26; \ | |
247 | lwi r27, r1, PTO+PT_R27; \ | |
248 | lwi r28, r1, PTO+PT_R28; \ | |
249 | lwi r29, r1, PTO+PT_R29; \ | |
250 | lwi r30, r1, PTO+PT_R30; \ | |
251 | lwi r31, r1, PTO+PT_R31; /* Restore cur task reg */ | |
252 | ||
253 | .text | |
254 | ||
255 | /* | |
256 | * User trap. | |
257 | * | |
258 | * System calls are handled here. | |
259 | * | |
260 | * Syscall protocol: | |
261 | * Syscall number in r12, args in r5-r10 | |
262 | * Return value in r3 | |
263 | * | |
264 | * Trap entered via brki instruction, so BIP bit is set, and interrupts | |
265 | * are masked. This is nice, means we don't have to CLI before state save | |
266 | */ | |
267 | C_ENTRY(_user_exception): | |
268 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ | |
269 | addi r14, r14, 4 /* return address is 4 byte after call */ | |
270 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ | |
271 | ||
272 | lwi r11, r0, TOPHYS(PER_CPU(KM));/* See if already in kernel mode.*/ | |
273 | beqi r11, 1f; /* Jump ahead if coming from user */ | |
274 | /* Kernel-mode state save. */ | |
275 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ | |
276 | tophys(r1,r11); | |
277 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ | |
278 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
279 | ||
280 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
281 | SAVE_REGS | |
282 | ||
283 | addi r11, r0, 1; /* Was in kernel-mode. */ | |
284 | swi r11, r1, PTO+PT_MODE; /* pt_regs -> kernel mode */ | |
285 | brid 2f; | |
286 | nop; /* Fill delay slot */ | |
287 | ||
288 | /* User-mode state save. */ | |
289 | 1: | |
290 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
291 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ | |
292 | tophys(r1,r1); | |
293 | lwi r1, r1, TS_THREAD_INFO; /* get stack from task_struct */ | |
294 | /* calculate kernel stack pointer from task struct 8k */ | |
295 | addik r1, r1, THREAD_SIZE; | |
296 | tophys(r1,r1); | |
297 | ||
298 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
299 | SAVE_REGS | |
300 | ||
301 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ | |
302 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
303 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ | |
304 | addi r11, r0, 1; | |
305 | swi r11, r0, TOPHYS(PER_CPU(KM)); /* Now we're in kernel-mode. */ | |
306 | 2: lwi r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ | |
307 | /* Save away the syscall number. */ | |
308 | swi r12, r1, PTO+PT_R0; | |
309 | tovirt(r1,r1) | |
310 | ||
ca54502b MS |
311 | /* where the trap should return need -8 to adjust for rtsd r15, 8*/ |
312 | /* Jump to the appropriate function for the system call number in r12 | |
313 | * (r12 is not preserved), or return an error if r12 is not valid. The LP | |
314 | * register should point to the location where | |
315 | * the called function should return. [note that MAKE_SYS_CALL uses label 1] */ | |
23575483 MS |
316 | |
317 | # Step into virtual mode. | |
318 | set_vms; | |
319 | addik r11, r0, 3f | |
320 | rtid r11, 0 | |
321 | nop | |
322 | 3: | |
323 | add r11, r0, CURRENT_TASK /* Get current task ptr into r11 */ | |
324 | lwi r11, r11, TS_THREAD_INFO /* get thread info */ | |
325 | lwi r11, r11, TI_FLAGS /* get flags in thread info */ | |
326 | andi r11, r11, _TIF_WORK_SYSCALL_MASK | |
327 | beqi r11, 4f | |
328 | ||
329 | addik r3, r0, -ENOSYS | |
330 | swi r3, r1, PTO + PT_R3 | |
331 | brlid r15, do_syscall_trace_enter | |
332 | addik r5, r1, PTO + PT_R0 | |
333 | ||
334 | # do_syscall_trace_enter returns the new syscall nr. | |
335 | addk r12, r0, r3 | |
336 | lwi r5, r1, PTO+PT_R5; | |
337 | lwi r6, r1, PTO+PT_R6; | |
338 | lwi r7, r1, PTO+PT_R7; | |
339 | lwi r8, r1, PTO+PT_R8; | |
340 | lwi r9, r1, PTO+PT_R9; | |
341 | lwi r10, r1, PTO+PT_R10; | |
342 | 4: | |
343 | /* Jump to the appropriate function for the system call number in r12 | |
344 | * (r12 is not preserved), or return an error if r12 is not valid. | |
345 | * The LP register should point to the location where the called function | |
346 | * should return. [note that MAKE_SYS_CALL uses label 1] */ | |
347 | /* See if the system call number is valid */ | |
ca54502b | 348 | addi r11, r12, -__NR_syscalls; |
23575483 | 349 | bgei r11,5f; |
ca54502b MS |
350 | /* Figure out which function to use for this system call. */ |
351 | /* Note Microblaze barrel shift is optional, so don't rely on it */ | |
352 | add r12, r12, r12; /* convert num -> ptr */ | |
353 | add r12, r12, r12; | |
354 | ||
355 | /* Trac syscalls and stored them to r0_ram */ | |
23575483 | 356 | lwi r3, r12, 0x400 + r0_ram |
ca54502b | 357 | addi r3, r3, 1 |
23575483 MS |
358 | swi r3, r12, 0x400 + r0_ram |
359 | ||
360 | # Find and jump into the syscall handler. | |
361 | lwi r12, r12, sys_call_table | |
362 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
363 | la r15, r0, ret_from_trap-8 | |
364 | bra r12 | |
ca54502b | 365 | |
ca54502b | 366 | /* The syscall number is invalid, return an error. */ |
23575483 | 367 | 5: |
ca54502b MS |
368 | addi r3, r0, -ENOSYS; |
369 | rtsd r15,8; /* looks like a normal subroutine return */ | |
370 | or r0, r0, r0 | |
371 | ||
372 | ||
23575483 | 373 | /* Entry point used to return from a syscall/trap */ |
ca54502b MS |
374 | /* We re-enable BIP bit before state restore */ |
375 | C_ENTRY(ret_from_trap): | |
376 | set_bip; /* Ints masked for state restore*/ | |
377 | lwi r11, r1, PTO+PT_MODE; | |
378 | /* See if returning to kernel mode, if so, skip resched &c. */ | |
379 | bnei r11, 2f; | |
380 | ||
23575483 MS |
381 | /* We're returning to user mode, so check for various conditions that |
382 | * trigger rescheduling. */ | |
383 | # FIXME: Restructure all these flag checks. | |
384 | add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
385 | lwi r11, r11, TS_THREAD_INFO; /* get thread info */ | |
386 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
387 | andi r11, r11, _TIF_WORK_SYSCALL_MASK | |
388 | beqi r11, 1f | |
389 | ||
390 | swi r3, r1, PTO + PT_R3 | |
391 | swi r4, r1, PTO + PT_R4 | |
392 | brlid r15, do_syscall_trace_leave | |
393 | addik r5, r1, PTO + PT_R0 | |
394 | lwi r3, r1, PTO + PT_R3 | |
395 | lwi r4, r1, PTO + PT_R4 | |
396 | 1: | |
397 | ||
ca54502b MS |
398 | /* We're returning to user mode, so check for various conditions that |
399 | * trigger rescheduling. */ | |
400 | /* Get current task ptr into r11 */ | |
401 | add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
402 | lwi r11, r11, TS_THREAD_INFO; /* get thread info */ | |
403 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
404 | andi r11, r11, _TIF_NEED_RESCHED; | |
405 | beqi r11, 5f; | |
406 | ||
407 | swi r3, r1, PTO + PT_R3; /* store syscall result */ | |
408 | swi r4, r1, PTO + PT_R4; | |
409 | bralid r15, schedule; /* Call scheduler */ | |
410 | nop; /* delay slot */ | |
411 | lwi r3, r1, PTO + PT_R3; /* restore syscall result */ | |
412 | lwi r4, r1, PTO + PT_R4; | |
413 | ||
414 | /* Maybe handle a signal */ | |
415 | 5: add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
416 | lwi r11, r11, TS_THREAD_INFO; /* get thread info */ | |
417 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
418 | andi r11, r11, _TIF_SIGPENDING; | |
419 | beqi r11, 1f; /* Signals to handle, handle them */ | |
420 | ||
421 | swi r3, r1, PTO + PT_R3; /* store syscall result */ | |
422 | swi r4, r1, PTO + PT_R4; | |
423 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ | |
424 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ | |
425 | addi r7, r0, 1; /* Arg 3: int in_syscall */ | |
426 | bralid r15, do_signal; /* Handle any signals */ | |
427 | nop; | |
428 | lwi r3, r1, PTO + PT_R3; /* restore syscall result */ | |
429 | lwi r4, r1, PTO + PT_R4; | |
430 | ||
431 | /* Finally, return to user state. */ | |
432 | 1: swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ | |
433 | add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
434 | swi r11, r0, PER_CPU(CURRENT_SAVE); /* save current */ | |
435 | VM_OFF; | |
436 | tophys(r1,r1); | |
437 | RESTORE_REGS; | |
438 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
439 | lwi r1, r1, PT_R1 - PT_SIZE;/* Restore user stack pointer. */ | |
440 | bri 6f; | |
441 | ||
442 | /* Return to kernel state. */ | |
443 | 2: VM_OFF; | |
444 | tophys(r1,r1); | |
445 | RESTORE_REGS; | |
446 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
447 | tovirt(r1,r1); | |
448 | 6: | |
449 | TRAP_return: /* Make global symbol for debugging */ | |
450 | rtbd r14, 0; /* Instructions to return from an IRQ */ | |
451 | nop; | |
452 | ||
453 | ||
454 | /* These syscalls need access to the struct pt_regs on the stack, so we | |
455 | implement them in assembly (they're basically all wrappers anyway). */ | |
456 | ||
457 | C_ENTRY(sys_fork_wrapper): | |
458 | addi r5, r0, SIGCHLD /* Arg 0: flags */ | |
459 | lwi r6, r1, PTO+PT_R1 /* Arg 1: child SP (use parent's) */ | |
460 | la r7, r1, PTO /* Arg 2: parent context */ | |
461 | add r8. r0, r0 /* Arg 3: (unused) */ | |
462 | add r9, r0, r0; /* Arg 4: (unused) */ | |
463 | add r10, r0, r0; /* Arg 5: (unused) */ | |
464 | brid do_fork /* Do real work (tail-call) */ | |
465 | nop; | |
466 | ||
467 | /* This the initial entry point for a new child thread, with an appropriate | |
468 | stack in place that makes it look the the child is in the middle of an | |
469 | syscall. This function is actually `returned to' from switch_thread | |
470 | (copy_thread makes ret_from_fork the return address in each new thread's | |
471 | saved context). */ | |
472 | C_ENTRY(ret_from_fork): | |
473 | bralid r15, schedule_tail; /* ...which is schedule_tail's arg */ | |
474 | add r3, r5, r0; /* switch_thread returns the prev task */ | |
475 | /* ( in the delay slot ) */ | |
476 | add r3, r0, r0; /* Child's fork call should return 0. */ | |
477 | brid ret_from_trap; /* Do normal trap return */ | |
478 | nop; | |
479 | ||
e513588f AB |
480 | C_ENTRY(sys_vfork): |
481 | brid microblaze_vfork /* Do real work (tail-call) */ | |
ca54502b | 482 | la r5, r1, PTO |
ca54502b | 483 | |
e513588f | 484 | C_ENTRY(sys_clone): |
ca54502b MS |
485 | bnei r6, 1f; /* See if child SP arg (arg 1) is 0. */ |
486 | lwi r6, r1, PTO+PT_R1; /* If so, use paret's stack ptr */ | |
487 | 1: la r7, r1, PTO; /* Arg 2: parent context */ | |
488 | add r8, r0, r0; /* Arg 3: (unused) */ | |
489 | add r9, r0, r0; /* Arg 4: (unused) */ | |
490 | add r10, r0, r0; /* Arg 5: (unused) */ | |
491 | brid do_fork /* Do real work (tail-call) */ | |
492 | nop; | |
493 | ||
e513588f | 494 | C_ENTRY(sys_execve): |
ca54502b | 495 | la r8, r1, PTO; /* add user context as 4th arg */ |
e513588f | 496 | brid microblaze_execve; /* Do real work (tail-call).*/ |
ca54502b MS |
497 | nop; |
498 | ||
ca54502b MS |
499 | C_ENTRY(sys_rt_sigsuspend_wrapper): |
500 | swi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
501 | swi r4, r1, PTO+PT_R4; | |
502 | la r7, r1, PTO; /* add user context as 3rd arg */ | |
503 | brlid r15, sys_rt_sigsuspend; /* Do real work.*/ | |
504 | nop; | |
505 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
506 | lwi r4, r1, PTO+PT_R4; | |
507 | bri ret_from_trap /* fall through will not work here due to align */ | |
508 | nop; | |
509 | ||
ca54502b MS |
510 | C_ENTRY(sys_rt_sigreturn_wrapper): |
511 | swi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
512 | swi r4, r1, PTO+PT_R4; | |
513 | la r5, r1, PTO; /* add user context as 1st arg */ | |
514 | brlid r15, sys_rt_sigreturn /* Do real work */ | |
515 | nop; | |
516 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
517 | lwi r4, r1, PTO+PT_R4; | |
518 | bri ret_from_trap /* fall through will not work here due to align */ | |
519 | nop; | |
520 | ||
521 | /* | |
522 | * HW EXCEPTION rutine start | |
523 | */ | |
524 | ||
525 | #define SAVE_STATE \ | |
526 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ \ | |
527 | set_bip; /*equalize initial state for all possible entries*/\ | |
528 | clear_eip; \ | |
529 | enable_irq; \ | |
530 | set_ee; \ | |
531 | /* See if already in kernel mode.*/ \ | |
532 | lwi r11, r0, TOPHYS(PER_CPU(KM)); \ | |
533 | beqi r11, 1f; /* Jump ahead if coming from user */\ | |
534 | /* Kernel-mode state save. */ \ | |
535 | /* Reload kernel stack-ptr. */ \ | |
536 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ | |
537 | tophys(r1,r11); \ | |
538 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ \ | |
539 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ | |
540 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ | |
541 | /* store return registers separately because \ | |
542 | * this macros is use for others exceptions */ \ | |
543 | swi r3, r1, PTO + PT_R3; \ | |
544 | swi r4, r1, PTO + PT_R4; \ | |
545 | SAVE_REGS \ | |
546 | /* PC, before IRQ/trap - this is one instruction above */ \ | |
547 | swi r17, r1, PTO+PT_PC; \ | |
548 | \ | |
549 | addi r11, r0, 1; /* Was in kernel-mode. */ \ | |
550 | swi r11, r1, PTO+PT_MODE; \ | |
551 | brid 2f; \ | |
552 | nop; /* Fill delay slot */ \ | |
553 | 1: /* User-mode state save. */ \ | |
554 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ | |
555 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\ | |
556 | tophys(r1,r1); \ | |
557 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ \ | |
558 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */\ | |
559 | tophys(r1,r1); \ | |
560 | \ | |
561 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ | |
562 | /* store return registers separately because this macros \ | |
563 | * is use for others exceptions */ \ | |
564 | swi r3, r1, PTO + PT_R3; \ | |
565 | swi r4, r1, PTO + PT_R4; \ | |
566 | SAVE_REGS \ | |
567 | /* PC, before IRQ/trap - this is one instruction above FIXME*/ \ | |
568 | swi r17, r1, PTO+PT_PC; \ | |
569 | \ | |
570 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ \ | |
571 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ | |
572 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ \ | |
573 | addi r11, r0, 1; \ | |
574 | swi r11, r0, TOPHYS(PER_CPU(KM)); /* Now we're in kernel-mode.*/\ | |
575 | 2: lwi r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\ | |
576 | /* Save away the syscall number. */ \ | |
577 | swi r0, r1, PTO+PT_R0; \ | |
578 | tovirt(r1,r1) | |
579 | ||
580 | C_ENTRY(full_exception_trap): | |
581 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ | |
582 | /* adjust exception address for privileged instruction | |
583 | * for finding where is it */ | |
584 | addik r17, r17, -4 | |
585 | SAVE_STATE /* Save registers */ | |
586 | /* FIXME this can be store directly in PT_ESR reg. | |
587 | * I tested it but there is a fault */ | |
588 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
589 | la r15, r0, ret_from_exc - 8 | |
590 | la r5, r1, PTO /* parameter struct pt_regs * regs */ | |
591 | mfs r6, resr | |
592 | nop | |
593 | mfs r7, rfsr; /* save FSR */ | |
594 | nop | |
131e4e97 MS |
595 | mts rfsr, r0; /* Clear sticky fsr */ |
596 | nop | |
ca54502b MS |
597 | la r12, r0, full_exception |
598 | set_vms; | |
599 | rtbd r12, 0; | |
600 | nop; | |
601 | ||
602 | /* | |
603 | * Unaligned data trap. | |
604 | * | |
605 | * Unaligned data trap last on 4k page is handled here. | |
606 | * | |
607 | * Trap entered via exception, so EE bit is set, and interrupts | |
608 | * are masked. This is nice, means we don't have to CLI before state save | |
609 | * | |
610 | * The assembler routine is in "arch/microblaze/kernel/hw_exception_handler.S" | |
611 | */ | |
612 | C_ENTRY(unaligned_data_trap): | |
613 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ | |
614 | SAVE_STATE /* Save registers.*/ | |
615 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
616 | la r15, r0, ret_from_exc-8 | |
617 | mfs r3, resr /* ESR */ | |
618 | nop | |
619 | mfs r4, rear /* EAR */ | |
620 | nop | |
621 | la r7, r1, PTO /* parameter struct pt_regs * regs */ | |
622 | la r12, r0, _unaligned_data_exception | |
623 | set_vms; | |
624 | rtbd r12, 0; /* interrupts enabled */ | |
625 | nop; | |
626 | ||
627 | /* | |
628 | * Page fault traps. | |
629 | * | |
630 | * If the real exception handler (from hw_exception_handler.S) didn't find | |
631 | * the mapping for the process, then we're thrown here to handle such situation. | |
632 | * | |
633 | * Trap entered via exceptions, so EE bit is set, and interrupts | |
634 | * are masked. This is nice, means we don't have to CLI before state save | |
635 | * | |
636 | * Build a standard exception frame for TLB Access errors. All TLB exceptions | |
637 | * will bail out to this point if they can't resolve the lightweight TLB fault. | |
638 | * | |
639 | * The C function called is in "arch/microblaze/mm/fault.c", declared as: | |
640 | * void do_page_fault(struct pt_regs *regs, | |
641 | * unsigned long address, | |
642 | * unsigned long error_code) | |
643 | */ | |
644 | /* data and intruction trap - which is choose is resolved int fault.c */ | |
645 | C_ENTRY(page_fault_data_trap): | |
646 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ | |
647 | SAVE_STATE /* Save registers.*/ | |
648 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
649 | la r15, r0, ret_from_exc-8 | |
650 | la r5, r1, PTO /* parameter struct pt_regs * regs */ | |
651 | mfs r6, rear /* parameter unsigned long address */ | |
652 | nop | |
653 | mfs r7, resr /* parameter unsigned long error_code */ | |
654 | nop | |
655 | la r12, r0, do_page_fault | |
656 | set_vms; | |
657 | rtbd r12, 0; /* interrupts enabled */ | |
658 | nop; | |
659 | ||
660 | C_ENTRY(page_fault_instr_trap): | |
661 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ | |
662 | SAVE_STATE /* Save registers.*/ | |
663 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ | |
664 | la r15, r0, ret_from_exc-8 | |
665 | la r5, r1, PTO /* parameter struct pt_regs * regs */ | |
666 | mfs r6, rear /* parameter unsigned long address */ | |
667 | nop | |
668 | ori r7, r0, 0 /* parameter unsigned long error_code */ | |
669 | la r12, r0, do_page_fault | |
670 | set_vms; | |
671 | rtbd r12, 0; /* interrupts enabled */ | |
672 | nop; | |
673 | ||
674 | /* Entry point used to return from an exception. */ | |
675 | C_ENTRY(ret_from_exc): | |
676 | set_bip; /* Ints masked for state restore*/ | |
677 | lwi r11, r1, PTO+PT_MODE; | |
678 | bnei r11, 2f; /* See if returning to kernel mode, */ | |
679 | /* ... if so, skip resched &c. */ | |
680 | ||
681 | /* We're returning to user mode, so check for various conditions that | |
682 | trigger rescheduling. */ | |
683 | /* Get current task ptr into r11 */ | |
684 | add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
685 | lwi r11, r11, TS_THREAD_INFO; /* get thread info */ | |
686 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
687 | andi r11, r11, _TIF_NEED_RESCHED; | |
688 | beqi r11, 5f; | |
689 | ||
690 | /* Call the scheduler before returning from a syscall/trap. */ | |
691 | bralid r15, schedule; /* Call scheduler */ | |
692 | nop; /* delay slot */ | |
693 | ||
694 | /* Maybe handle a signal */ | |
695 | 5: add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
696 | lwi r11, r11, TS_THREAD_INFO; /* get thread info */ | |
697 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
698 | andi r11, r11, _TIF_SIGPENDING; | |
699 | beqi r11, 1f; /* Signals to handle, handle them */ | |
700 | ||
701 | /* | |
702 | * Handle a signal return; Pending signals should be in r18. | |
703 | * | |
704 | * Not all registers are saved by the normal trap/interrupt entry | |
705 | * points (for instance, call-saved registers (because the normal | |
706 | * C-compiler calling sequence in the kernel makes sure they're | |
707 | * preserved), and call-clobbered registers in the case of | |
708 | * traps), but signal handlers may want to examine or change the | |
709 | * complete register state. Here we save anything not saved by | |
710 | * the normal entry sequence, so that it may be safely restored | |
711 | * (in a possibly modified form) after do_signal returns. | |
712 | * store return registers separately because this macros is use | |
713 | * for others exceptions */ | |
714 | swi r3, r1, PTO + PT_R3; | |
715 | swi r4, r1, PTO + PT_R4; | |
716 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ | |
717 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ | |
718 | addi r7, r0, 0; /* Arg 3: int in_syscall */ | |
719 | bralid r15, do_signal; /* Handle any signals */ | |
720 | nop; | |
721 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
722 | lwi r4, r1, PTO+PT_R4; | |
723 | ||
724 | /* Finally, return to user state. */ | |
725 | 1: swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ | |
726 | add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
727 | swi r11, r0, PER_CPU(CURRENT_SAVE); /* save current */ | |
728 | VM_OFF; | |
729 | tophys(r1,r1); | |
730 | ||
731 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
732 | lwi r4, r1, PTO+PT_R4; | |
733 | RESTORE_REGS; | |
734 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
735 | ||
736 | lwi r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer. */ | |
737 | bri 6f; | |
738 | /* Return to kernel state. */ | |
739 | 2: VM_OFF; | |
740 | tophys(r1,r1); | |
741 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
742 | lwi r4, r1, PTO+PT_R4; | |
743 | RESTORE_REGS; | |
744 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
745 | ||
746 | tovirt(r1,r1); | |
747 | 6: | |
748 | EXC_return: /* Make global symbol for debugging */ | |
749 | rtbd r14, 0; /* Instructions to return from an IRQ */ | |
750 | nop; | |
751 | ||
752 | /* | |
753 | * HW EXCEPTION rutine end | |
754 | */ | |
755 | ||
756 | /* | |
757 | * Hardware maskable interrupts. | |
758 | * | |
759 | * The stack-pointer (r1) should have already been saved to the memory | |
760 | * location PER_CPU(ENTRY_SP). | |
761 | */ | |
762 | C_ENTRY(_interrupt): | |
763 | /* MS: we are in physical address */ | |
764 | /* Save registers, switch to proper stack, convert SP to virtual.*/ | |
765 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) | |
766 | swi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); | |
767 | /* MS: See if already in kernel mode. */ | |
768 | lwi r11, r0, TOPHYS(PER_CPU(KM)); | |
769 | beqi r11, 1f; /* MS: Jump ahead if coming from user */ | |
770 | ||
771 | /* Kernel-mode state save. */ | |
772 | or r11, r1, r0 | |
773 | tophys(r1,r11); /* MS: I have in r1 physical address where stack is */ | |
774 | /* MS: Save original SP - position PT_R1 to next stack frame 4 *1 - 152*/ | |
775 | swi r11, r1, (PT_R1 - PT_SIZE); | |
776 | /* MS: restore r11 because of saving in SAVE_REGS */ | |
777 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); | |
778 | /* save registers */ | |
779 | /* MS: Make room on the stack -> activation record */ | |
780 | addik r1, r1, -STATE_SAVE_SIZE; | |
781 | /* MS: store return registers separately because | |
782 | * this macros is use for others exceptions */ | |
783 | swi r3, r1, PTO + PT_R3; | |
784 | swi r4, r1, PTO + PT_R4; | |
785 | SAVE_REGS | |
786 | /* MS: store mode */ | |
787 | addi r11, r0, 1; /* MS: Was in kernel-mode. */ | |
788 | swi r11, r1, PTO + PT_MODE; /* MS: and save it */ | |
789 | brid 2f; | |
790 | nop; /* MS: Fill delay slot */ | |
791 | ||
792 | 1: | |
793 | /* User-mode state save. */ | |
794 | /* MS: restore r11 -> FIXME move before SAVE_REG */ | |
795 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); | |
796 | /* MS: get the saved current */ | |
797 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); | |
798 | tophys(r1,r1); | |
799 | lwi r1, r1, TS_THREAD_INFO; | |
800 | addik r1, r1, THREAD_SIZE; | |
801 | tophys(r1,r1); | |
802 | /* save registers */ | |
803 | addik r1, r1, -STATE_SAVE_SIZE; | |
804 | swi r3, r1, PTO+PT_R3; | |
805 | swi r4, r1, PTO+PT_R4; | |
806 | SAVE_REGS | |
807 | /* calculate mode */ | |
808 | swi r0, r1, PTO + PT_MODE; | |
809 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
810 | swi r11, r1, PTO+PT_R1; | |
811 | /* setup kernel mode to KM */ | |
812 | addi r11, r0, 1; | |
813 | swi r11, r0, TOPHYS(PER_CPU(KM)); | |
814 | ||
815 | 2: | |
816 | lwi r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); | |
817 | swi r0, r1, PTO + PT_R0; | |
818 | tovirt(r1,r1) | |
819 | la r5, r1, PTO; | |
820 | set_vms; | |
821 | la r11, r0, do_IRQ; | |
822 | la r15, r0, irq_call; | |
823 | irq_call:rtbd r11, 0; | |
824 | nop; | |
825 | ||
826 | /* MS: we are in virtual mode */ | |
827 | ret_from_irq: | |
828 | lwi r11, r1, PTO + PT_MODE; | |
829 | bnei r11, 2f; | |
830 | ||
831 | add r11, r0, CURRENT_TASK; | |
832 | lwi r11, r11, TS_THREAD_INFO; | |
833 | lwi r11, r11, TI_FLAGS; /* MS: get flags from thread info */ | |
834 | andi r11, r11, _TIF_NEED_RESCHED; | |
835 | beqi r11, 5f | |
836 | bralid r15, schedule; | |
837 | nop; /* delay slot */ | |
838 | ||
839 | /* Maybe handle a signal */ | |
840 | 5: add r11, r0, CURRENT_TASK; | |
841 | lwi r11, r11, TS_THREAD_INFO; /* MS: get thread info */ | |
842 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
843 | andi r11, r11, _TIF_SIGPENDING; | |
844 | beqid r11, no_intr_resched | |
845 | /* Handle a signal return; Pending signals should be in r18. */ | |
846 | addi r7, r0, 0; /* Arg 3: int in_syscall */ | |
847 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ | |
848 | bralid r15, do_signal; /* Handle any signals */ | |
849 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ | |
850 | ||
851 | /* Finally, return to user state. */ | |
852 | no_intr_resched: | |
853 | /* Disable interrupts, we are now committed to the state restore */ | |
854 | disable_irq | |
855 | swi r0, r0, PER_CPU(KM); /* MS: Now officially in user state. */ | |
856 | add r11, r0, CURRENT_TASK; | |
857 | swi r11, r0, PER_CPU(CURRENT_SAVE); | |
858 | VM_OFF; | |
859 | tophys(r1,r1); | |
860 | lwi r3, r1, PTO + PT_R3; /* MS: restore saved r3, r4 registers */ | |
861 | lwi r4, r1, PTO + PT_R4; | |
862 | RESTORE_REGS | |
863 | addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */ | |
864 | lwi r1, r1, PT_R1 - PT_SIZE; | |
865 | bri 6f; | |
866 | /* MS: Return to kernel state. */ | |
867 | 2: VM_OFF /* MS: turn off MMU */ | |
868 | tophys(r1,r1) | |
869 | lwi r3, r1, PTO + PT_R3; /* MS: restore saved r3, r4 registers */ | |
870 | lwi r4, r1, PTO + PT_R4; | |
871 | RESTORE_REGS | |
872 | addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */ | |
873 | tovirt(r1,r1); | |
874 | 6: | |
875 | IRQ_return: /* MS: Make global symbol for debugging */ | |
876 | rtid r14, 0 | |
877 | nop | |
878 | ||
879 | /* | |
880 | * `Debug' trap | |
881 | * We enter dbtrap in "BIP" (breakpoint) mode. | |
882 | * So we exit the breakpoint mode with an 'rtbd' and proceed with the | |
883 | * original dbtrap. | |
884 | * however, wait to save state first | |
885 | */ | |
886 | C_ENTRY(_debug_exception): | |
887 | /* BIP bit is set on entry, no interrupts can occur */ | |
888 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) | |
889 | ||
890 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ | |
891 | set_bip; /*equalize initial state for all possible entries*/ | |
892 | clear_eip; | |
893 | enable_irq; | |
894 | lwi r11, r0, TOPHYS(PER_CPU(KM));/* See if already in kernel mode.*/ | |
895 | beqi r11, 1f; /* Jump ahead if coming from user */ | |
896 | /* Kernel-mode state save. */ | |
897 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ | |
898 | tophys(r1,r11); | |
899 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ | |
900 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
901 | ||
902 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
903 | swi r3, r1, PTO + PT_R3; | |
904 | swi r4, r1, PTO + PT_R4; | |
905 | SAVE_REGS; | |
906 | ||
907 | addi r11, r0, 1; /* Was in kernel-mode. */ | |
908 | swi r11, r1, PTO + PT_MODE; | |
909 | brid 2f; | |
910 | nop; /* Fill delay slot */ | |
911 | 1: /* User-mode state save. */ | |
912 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ | |
913 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ | |
914 | tophys(r1,r1); | |
915 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ | |
916 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */ | |
917 | tophys(r1,r1); | |
918 | ||
919 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ | |
920 | swi r3, r1, PTO + PT_R3; | |
921 | swi r4, r1, PTO + PT_R4; | |
922 | SAVE_REGS; | |
923 | ||
924 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ | |
925 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); | |
926 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ | |
927 | addi r11, r0, 1; | |
928 | swi r11, r0, TOPHYS(PER_CPU(KM)); /* Now we're in kernel-mode. */ | |
929 | 2: lwi r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ | |
930 | /* Save away the syscall number. */ | |
931 | swi r0, r1, PTO+PT_R0; | |
932 | tovirt(r1,r1) | |
933 | ||
934 | addi r5, r0, SIGTRAP /* send the trap signal */ | |
935 | add r6, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
936 | addk r7, r0, r0 /* 3rd param zero */ | |
937 | ||
938 | set_vms; | |
939 | la r11, r0, send_sig; | |
940 | la r15, r0, dbtrap_call; | |
941 | dbtrap_call: rtbd r11, 0; | |
942 | nop; | |
943 | ||
944 | set_bip; /* Ints masked for state restore*/ | |
945 | lwi r11, r1, PTO+PT_MODE; | |
946 | bnei r11, 2f; | |
947 | ||
948 | /* Get current task ptr into r11 */ | |
949 | add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
950 | lwi r11, r11, TS_THREAD_INFO; /* get thread info */ | |
951 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
952 | andi r11, r11, _TIF_NEED_RESCHED; | |
953 | beqi r11, 5f; | |
954 | ||
955 | /* Call the scheduler before returning from a syscall/trap. */ | |
956 | ||
957 | bralid r15, schedule; /* Call scheduler */ | |
958 | nop; /* delay slot */ | |
959 | /* XXX Is PT_DTRACE handling needed here? */ | |
960 | /* XXX m68knommu also checks TASK_STATE & TASK_COUNTER here. */ | |
961 | ||
962 | /* Maybe handle a signal */ | |
963 | 5: add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
964 | lwi r11, r11, TS_THREAD_INFO; /* get thread info */ | |
965 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ | |
966 | andi r11, r11, _TIF_SIGPENDING; | |
967 | beqi r11, 1f; /* Signals to handle, handle them */ | |
968 | ||
969 | /* Handle a signal return; Pending signals should be in r18. */ | |
970 | /* Not all registers are saved by the normal trap/interrupt entry | |
971 | points (for instance, call-saved registers (because the normal | |
972 | C-compiler calling sequence in the kernel makes sure they're | |
973 | preserved), and call-clobbered registers in the case of | |
974 | traps), but signal handlers may want to examine or change the | |
975 | complete register state. Here we save anything not saved by | |
976 | the normal entry sequence, so that it may be safely restored | |
977 | (in a possibly modified form) after do_signal returns. */ | |
978 | ||
979 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ | |
980 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ | |
981 | addi r7, r0, 0; /* Arg 3: int in_syscall */ | |
982 | bralid r15, do_signal; /* Handle any signals */ | |
983 | nop; | |
984 | ||
985 | ||
986 | /* Finally, return to user state. */ | |
987 | 1: swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ | |
988 | add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ | |
989 | swi r11, r0, PER_CPU(CURRENT_SAVE); /* save current */ | |
990 | VM_OFF; | |
991 | tophys(r1,r1); | |
992 | ||
993 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
994 | lwi r4, r1, PTO+PT_R4; | |
995 | RESTORE_REGS | |
996 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
997 | ||
998 | ||
999 | lwi r1, r1, PT_R1 - PT_SIZE; | |
1000 | /* Restore user stack pointer. */ | |
1001 | bri 6f; | |
1002 | ||
1003 | /* Return to kernel state. */ | |
1004 | 2: VM_OFF; | |
1005 | tophys(r1,r1); | |
1006 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ | |
1007 | lwi r4, r1, PTO+PT_R4; | |
1008 | RESTORE_REGS | |
1009 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ | |
1010 | ||
1011 | tovirt(r1,r1); | |
1012 | 6: | |
1013 | DBTRAP_return: /* Make global symbol for debugging */ | |
1014 | rtbd r14, 0; /* Instructions to return from an IRQ */ | |
1015 | nop; | |
1016 | ||
1017 | ||
1018 | ||
1019 | ENTRY(_switch_to) | |
1020 | /* prepare return value */ | |
1021 | addk r3, r0, r31 | |
1022 | ||
1023 | /* save registers in cpu_context */ | |
1024 | /* use r11 and r12, volatile registers, as temp register */ | |
1025 | /* give start of cpu_context for previous process */ | |
1026 | addik r11, r5, TI_CPU_CONTEXT | |
1027 | swi r1, r11, CC_R1 | |
1028 | swi r2, r11, CC_R2 | |
1029 | /* skip volatile registers. | |
1030 | * they are saved on stack when we jumped to _switch_to() */ | |
1031 | /* dedicated registers */ | |
1032 | swi r13, r11, CC_R13 | |
1033 | swi r14, r11, CC_R14 | |
1034 | swi r15, r11, CC_R15 | |
1035 | swi r16, r11, CC_R16 | |
1036 | swi r17, r11, CC_R17 | |
1037 | swi r18, r11, CC_R18 | |
1038 | /* save non-volatile registers */ | |
1039 | swi r19, r11, CC_R19 | |
1040 | swi r20, r11, CC_R20 | |
1041 | swi r21, r11, CC_R21 | |
1042 | swi r22, r11, CC_R22 | |
1043 | swi r23, r11, CC_R23 | |
1044 | swi r24, r11, CC_R24 | |
1045 | swi r25, r11, CC_R25 | |
1046 | swi r26, r11, CC_R26 | |
1047 | swi r27, r11, CC_R27 | |
1048 | swi r28, r11, CC_R28 | |
1049 | swi r29, r11, CC_R29 | |
1050 | swi r30, r11, CC_R30 | |
1051 | /* special purpose registers */ | |
1052 | mfs r12, rmsr | |
1053 | nop | |
1054 | swi r12, r11, CC_MSR | |
1055 | mfs r12, rear | |
1056 | nop | |
1057 | swi r12, r11, CC_EAR | |
1058 | mfs r12, resr | |
1059 | nop | |
1060 | swi r12, r11, CC_ESR | |
1061 | mfs r12, rfsr | |
1062 | nop | |
1063 | swi r12, r11, CC_FSR | |
1064 | ||
1065 | /* update r31, the current */ | |
1066 | lwi r31, r6, TI_TASK/* give me pointer to task which will be next */ | |
1067 | /* stored it to current_save too */ | |
1068 | swi r31, r0, PER_CPU(CURRENT_SAVE) | |
1069 | ||
1070 | /* get new process' cpu context and restore */ | |
1071 | /* give me start where start context of next task */ | |
1072 | addik r11, r6, TI_CPU_CONTEXT | |
1073 | ||
1074 | /* non-volatile registers */ | |
1075 | lwi r30, r11, CC_R30 | |
1076 | lwi r29, r11, CC_R29 | |
1077 | lwi r28, r11, CC_R28 | |
1078 | lwi r27, r11, CC_R27 | |
1079 | lwi r26, r11, CC_R26 | |
1080 | lwi r25, r11, CC_R25 | |
1081 | lwi r24, r11, CC_R24 | |
1082 | lwi r23, r11, CC_R23 | |
1083 | lwi r22, r11, CC_R22 | |
1084 | lwi r21, r11, CC_R21 | |
1085 | lwi r20, r11, CC_R20 | |
1086 | lwi r19, r11, CC_R19 | |
1087 | /* dedicated registers */ | |
1088 | lwi r18, r11, CC_R18 | |
1089 | lwi r17, r11, CC_R17 | |
1090 | lwi r16, r11, CC_R16 | |
1091 | lwi r15, r11, CC_R15 | |
1092 | lwi r14, r11, CC_R14 | |
1093 | lwi r13, r11, CC_R13 | |
1094 | /* skip volatile registers */ | |
1095 | lwi r2, r11, CC_R2 | |
1096 | lwi r1, r11, CC_R1 | |
1097 | ||
1098 | /* special purpose registers */ | |
1099 | lwi r12, r11, CC_FSR | |
1100 | mts rfsr, r12 | |
1101 | nop | |
1102 | lwi r12, r11, CC_MSR | |
1103 | mts rmsr, r12 | |
1104 | nop | |
1105 | ||
1106 | rtsd r15, 8 | |
1107 | nop | |
1108 | ||
1109 | ENTRY(_reset) | |
1110 | brai 0x70; /* Jump back to FS-boot */ | |
1111 | ||
1112 | ENTRY(_break) | |
1113 | mfs r5, rmsr | |
1114 | nop | |
1115 | swi r5, r0, 0x250 + TOPHYS(r0_ram) | |
1116 | mfs r5, resr | |
1117 | nop | |
1118 | swi r5, r0, 0x254 + TOPHYS(r0_ram) | |
1119 | bri 0 | |
1120 | ||
1121 | /* These are compiled and loaded into high memory, then | |
1122 | * copied into place in mach_early_setup */ | |
1123 | .section .init.ivt, "ax" | |
1124 | .org 0x0 | |
1125 | /* this is very important - here is the reset vector */ | |
1126 | /* in current MMU branch you don't care what is here - it is | |
1127 | * used from bootloader site - but this is correct for FS-BOOT */ | |
1128 | brai 0x70 | |
1129 | nop | |
1130 | brai TOPHYS(_user_exception); /* syscall handler */ | |
1131 | brai TOPHYS(_interrupt); /* Interrupt handler */ | |
1132 | brai TOPHYS(_break); /* nmi trap handler */ | |
1133 | brai TOPHYS(_hw_exception_handler); /* HW exception handler */ | |
1134 | ||
1135 | .org 0x60 | |
1136 | brai TOPHYS(_debug_exception); /* debug trap handler*/ | |
1137 | ||
1138 | .section .rodata,"a" | |
1139 | #include "syscall_table.S" | |
1140 | ||
1141 | syscall_table_size=(.-sys_call_table) | |
1142 |