blob: 9aa54def998516695827258958be988427337337 [file] [log] [blame]
Michal Simekca545022009-05-26 16:30:21 +02001/*
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
Michal Simek11d51362009-12-07 08:21:34 +010034#undef DEBUG
35
Michal Simekd8748e72011-01-31 15:04:43 +010036#ifdef DEBUG
37/* Create space for syscalls counting. */
38.section .data
39.global syscall_debug_table
40.align 4
41syscall_debug_table:
42 .space (__NR_syscalls * 4)
43#endif /* DEBUG */
44
Michal Simekca545022009-05-26 16:30:21 +020045#define C_ENTRY(name) .globl name; .align 4; name
46
47/*
48 * Various ways of setting and clearing BIP in flags reg.
49 * This is mucky, but necessary using microblaze version that
50 * allows msr ops to write to BIP
51 */
52#if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
53 .macro clear_bip
Michal Simek66f7de862010-06-22 17:52:47 +020054 msrclr r0, MSR_BIP
Michal Simekca545022009-05-26 16:30:21 +020055 .endm
56
57 .macro set_bip
Michal Simek66f7de862010-06-22 17:52:47 +020058 msrset r0, MSR_BIP
Michal Simekca545022009-05-26 16:30:21 +020059 .endm
60
61 .macro clear_eip
Michal Simek66f7de862010-06-22 17:52:47 +020062 msrclr r0, MSR_EIP
Michal Simekca545022009-05-26 16:30:21 +020063 .endm
64
65 .macro set_ee
Michal Simek66f7de862010-06-22 17:52:47 +020066 msrset r0, MSR_EE
Michal Simekca545022009-05-26 16:30:21 +020067 .endm
68
69 .macro disable_irq
Michal Simek66f7de862010-06-22 17:52:47 +020070 msrclr r0, MSR_IE
Michal Simekca545022009-05-26 16:30:21 +020071 .endm
72
73 .macro enable_irq
Michal Simek66f7de862010-06-22 17:52:47 +020074 msrset r0, MSR_IE
Michal Simekca545022009-05-26 16:30:21 +020075 .endm
76
77 .macro set_ums
Michal Simek66f7de862010-06-22 17:52:47 +020078 msrset r0, MSR_UMS
Michal Simek66f7de862010-06-22 17:52:47 +020079 msrclr r0, MSR_VMS
Michal Simekca545022009-05-26 16:30:21 +020080 .endm
81
82 .macro set_vms
Michal Simek66f7de862010-06-22 17:52:47 +020083 msrclr r0, MSR_UMS
Michal Simek66f7de862010-06-22 17:52:47 +020084 msrset r0, MSR_VMS
Michal Simekca545022009-05-26 16:30:21 +020085 .endm
86
Michal Simekb3180672010-06-22 17:46:27 +020087 .macro clear_ums
Michal Simek66f7de862010-06-22 17:52:47 +020088 msrclr r0, MSR_UMS
Michal Simekb3180672010-06-22 17:46:27 +020089 .endm
90
Michal Simekca545022009-05-26 16:30:21 +020091 .macro clear_vms_ums
Michal Simek66f7de862010-06-22 17:52:47 +020092 msrclr r0, MSR_VMS | MSR_UMS
Michal Simekca545022009-05-26 16:30:21 +020093 .endm
94#else
95 .macro clear_bip
96 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +020097 andi r11, r11, ~MSR_BIP
98 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +020099 .endm
100
101 .macro set_bip
102 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200103 ori r11, r11, MSR_BIP
104 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +0200105 .endm
106
107 .macro clear_eip
108 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200109 andi r11, r11, ~MSR_EIP
110 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +0200111 .endm
112
113 .macro set_ee
114 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200115 ori r11, r11, MSR_EE
116 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +0200117 .endm
118
119 .macro disable_irq
120 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200121 andi r11, r11, ~MSR_IE
122 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +0200123 .endm
124
125 .macro enable_irq
126 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200127 ori r11, r11, MSR_IE
128 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +0200129 .endm
130
131 .macro set_ums
132 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200133 ori r11, r11, MSR_VMS
134 andni r11, r11, MSR_UMS
135 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +0200136 .endm
137
138 .macro set_vms
139 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200140 ori r11, r11, MSR_VMS
141 andni r11, r11, MSR_UMS
142 mts rmsr, r11
Michal Simekca545022009-05-26 16:30:21 +0200143 .endm
144
Michal Simekb3180672010-06-22 17:46:27 +0200145 .macro clear_ums
146 mfs r11, rmsr
Michal Simekb3180672010-06-22 17:46:27 +0200147 andni r11, r11, MSR_UMS
148 mts rmsr,r11
Michal Simekb3180672010-06-22 17:46:27 +0200149 .endm
150
Michal Simekca545022009-05-26 16:30:21 +0200151 .macro clear_vms_ums
152 mfs r11, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200153 andni r11, r11, (MSR_VMS|MSR_UMS)
154 mts rmsr,r11
Michal Simekca545022009-05-26 16:30:21 +0200155 .endm
156#endif
157
158/* Define how to call high-level functions. With MMU, virtual mode must be
159 * enabled when calling the high-level function. Clobbers R11.
160 * VM_ON, VM_OFF, DO_JUMP_BIPCLR, DO_CALL
161 */
162
163/* turn on virtual protected mode save */
164#define VM_ON \
Michal Simeka4a94db2010-06-22 13:15:53 +0200165 set_ums; \
Michal Simekca545022009-05-26 16:30:21 +0200166 rted r0, 2f; \
Michal Simeka4a94db2010-06-22 13:15:53 +0200167 nop; \
1682:
Michal Simekca545022009-05-26 16:30:21 +0200169
170/* turn off virtual protected mode save and user mode save*/
171#define VM_OFF \
Michal Simeka4a94db2010-06-22 13:15:53 +0200172 clear_vms_ums; \
Michal Simekca545022009-05-26 16:30:21 +0200173 rted r0, TOPHYS(1f); \
Michal Simeka4a94db2010-06-22 13:15:53 +0200174 nop; \
1751:
Michal Simekca545022009-05-26 16:30:21 +0200176
177#define SAVE_REGS \
Michal Simek6e835572011-01-31 15:10:04 +0100178 swi r2, r1, PT_R2; /* Save SDA */ \
179 swi r3, r1, PT_R3; \
180 swi r4, r1, PT_R4; \
181 swi r5, r1, PT_R5; \
182 swi r6, r1, PT_R6; \
183 swi r7, r1, PT_R7; \
184 swi r8, r1, PT_R8; \
185 swi r9, r1, PT_R9; \
186 swi r10, r1, PT_R10; \
187 swi r11, r1, PT_R11; /* save clobbered regs after rval */\
188 swi r12, r1, PT_R12; \
189 swi r13, r1, PT_R13; /* Save SDA2 */ \
190 swi r14, r1, PT_PC; /* PC, before IRQ/trap */ \
191 swi r15, r1, PT_R15; /* Save LP */ \
192 swi r16, r1, PT_R16; \
193 swi r17, r1, PT_R17; \
194 swi r18, r1, PT_R18; /* Save asm scratch reg */ \
195 swi r19, r1, PT_R19; \
196 swi r20, r1, PT_R20; \
197 swi r21, r1, PT_R21; \
198 swi r22, r1, PT_R22; \
199 swi r23, r1, PT_R23; \
200 swi r24, r1, PT_R24; \
201 swi r25, r1, PT_R25; \
202 swi r26, r1, PT_R26; \
203 swi r27, r1, PT_R27; \
204 swi r28, r1, PT_R28; \
205 swi r29, r1, PT_R29; \
206 swi r30, r1, PT_R30; \
207 swi r31, r1, PT_R31; /* Save current task reg */ \
Michal Simekca545022009-05-26 16:30:21 +0200208 mfs r11, rmsr; /* save MSR */ \
Michal Simek6e835572011-01-31 15:10:04 +0100209 swi r11, r1, PT_MSR;
Michal Simekca545022009-05-26 16:30:21 +0200210
211#define RESTORE_REGS \
Michal Simek6e835572011-01-31 15:10:04 +0100212 lwi r11, r1, PT_MSR; \
Michal Simekca545022009-05-26 16:30:21 +0200213 mts rmsr , r11; \
Michal Simek6e835572011-01-31 15:10:04 +0100214 lwi r2, r1, PT_R2; /* restore SDA */ \
215 lwi r3, r1, PT_R3; \
216 lwi r4, r1, PT_R4; \
217 lwi r5, r1, PT_R5; \
218 lwi r6, r1, PT_R6; \
219 lwi r7, r1, PT_R7; \
220 lwi r8, r1, PT_R8; \
221 lwi r9, r1, PT_R9; \
222 lwi r10, r1, PT_R10; \
223 lwi r11, r1, PT_R11; /* restore clobbered regs after rval */\
224 lwi r12, r1, PT_R12; \
225 lwi r13, r1, PT_R13; /* restore SDA2 */ \
226 lwi r14, r1, PT_PC; /* RESTORE_LINK PC, before IRQ/trap */\
227 lwi r15, r1, PT_R15; /* restore LP */ \
228 lwi r16, r1, PT_R16; \
229 lwi r17, r1, PT_R17; \
230 lwi r18, r1, PT_R18; /* restore asm scratch reg */ \
231 lwi r19, r1, PT_R19; \
232 lwi r20, r1, PT_R20; \
233 lwi r21, r1, PT_R21; \
234 lwi r22, r1, PT_R22; \
235 lwi r23, r1, PT_R23; \
236 lwi r24, r1, PT_R24; \
237 lwi r25, r1, PT_R25; \
238 lwi r26, r1, PT_R26; \
239 lwi r27, r1, PT_R27; \
240 lwi r28, r1, PT_R28; \
241 lwi r29, r1, PT_R29; \
242 lwi r30, r1, PT_R30; \
243 lwi r31, r1, PT_R31; /* Restore cur task reg */
Michal Simekca545022009-05-26 16:30:21 +0200244
Michal Simeke5d2af22010-06-22 17:58:26 +0200245#define SAVE_STATE \
246 swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* save stack */ \
247 /* See if already in kernel mode.*/ \
248 mfs r1, rmsr; \
Michal Simeke5d2af22010-06-22 17:58:26 +0200249 andi r1, r1, MSR_UMS; \
250 bnei r1, 1f; \
251 /* Kernel-mode state save. */ \
252 /* Reload kernel stack-ptr. */ \
253 lwi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); \
Michal Simek287503f2010-06-22 18:16:07 +0200254 /* FIXME: I can add these two lines to one */ \
255 /* tophys(r1,r1); */ \
Michal Simek6e835572011-01-31 15:10:04 +0100256 /* addik r1, r1, -PT_SIZE; */ \
257 addik r1, r1, CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START - PT_SIZE; \
Michal Simeke5d2af22010-06-22 17:58:26 +0200258 SAVE_REGS \
Michal Simeke5d2af22010-06-22 17:58:26 +0200259 brid 2f; \
Michal Simek6e835572011-01-31 15:10:04 +0100260 swi r1, r1, PT_MODE; \
Michal Simeke5d2af22010-06-22 17:58:26 +02002611: /* User-mode state save. */ \
262 lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\
263 tophys(r1,r1); \
264 lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ \
Michal Simek287503f2010-06-22 18:16:07 +0200265 /* MS these three instructions can be added to one */ \
266 /* addik r1, r1, THREAD_SIZE; */ \
267 /* tophys(r1,r1); */ \
Michal Simek6e835572011-01-31 15:10:04 +0100268 /* addik r1, r1, -PT_SIZE; */ \
269 addik r1, r1, THREAD_SIZE + CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START - PT_SIZE; \
Michal Simeke5d2af22010-06-22 17:58:26 +0200270 SAVE_REGS \
Michal Simeke5d2af22010-06-22 17:58:26 +0200271 lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \
Michal Simek6e835572011-01-31 15:10:04 +0100272 swi r11, r1, PT_R1; /* Store user SP. */ \
273 swi r0, r1, PT_MODE; /* Was in user-mode. */ \
Michal Simeke5d2af22010-06-22 17:58:26 +0200274 /* MS: I am clearing UMS even in case when I come from kernel space */ \
275 clear_ums; \
2762: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));
277
Michal Simekca545022009-05-26 16:30:21 +0200278.text
279
280/*
281 * User trap.
282 *
283 * System calls are handled here.
284 *
285 * Syscall protocol:
286 * Syscall number in r12, args in r5-r10
287 * Return value in r3
288 *
289 * Trap entered via brki instruction, so BIP bit is set, and interrupts
290 * are masked. This is nice, means we don't have to CLI before state save
291 */
292C_ENTRY(_user_exception):
Michal Simek0e41c902010-06-22 21:11:49 +0200293 swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */
Michal Simek9da63452010-10-22 15:48:58 +1000294 addi r14, r14, 4 /* return address is 4 byte after call */
Michal Simekca545022009-05-26 16:30:21 +0200295
Michal Simekca545022009-05-26 16:30:21 +0200296 lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */
297 tophys(r1,r1);
298 lwi r1, r1, TS_THREAD_INFO; /* get stack from task_struct */
Michal Simek9da63452010-10-22 15:48:58 +1000299/* calculate kernel stack pointer from task struct 8k */
300 addik r1, r1, THREAD_SIZE;
301 tophys(r1,r1);
302
Michal Simek6e835572011-01-31 15:10:04 +0100303 addik r1, r1, -PT_SIZE; /* Make room on the stack. */
Michal Simekca545022009-05-26 16:30:21 +0200304 SAVE_REGS
Michal Simek6e835572011-01-31 15:10:04 +0100305 swi r0, r1, PT_R3
306 swi r0, r1, PT_R4
Michal Simekca545022009-05-26 16:30:21 +0200307
Michal Simek6e835572011-01-31 15:10:04 +0100308 swi r0, r1, PT_MODE; /* Was in user-mode. */
Michal Simekca545022009-05-26 16:30:21 +0200309 lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP));
Michal Simek6e835572011-01-31 15:10:04 +0100310 swi r11, r1, PT_R1; /* Store user SP. */
Michal Simek25f6e592010-06-22 18:29:05 +0200311 clear_ums;
Michal Simek9da63452010-10-22 15:48:58 +10003122: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));
Michal Simekca545022009-05-26 16:30:21 +0200313 /* Save away the syscall number. */
Michal Simek6e835572011-01-31 15:10:04 +0100314 swi r12, r1, PT_R0;
Michal Simekca545022009-05-26 16:30:21 +0200315 tovirt(r1,r1)
316
Michal Simekca545022009-05-26 16:30:21 +0200317/* where the trap should return need -8 to adjust for rtsd r15, 8*/
318/* Jump to the appropriate function for the system call number in r12
319 * (r12 is not preserved), or return an error if r12 is not valid. The LP
320 * register should point to the location where
321 * the called function should return. [note that MAKE_SYS_CALL uses label 1] */
Michal Simek23575482009-08-24 13:26:04 +0200322
Michal Simek25f6e592010-06-22 18:29:05 +0200323 /* Step into virtual mode */
324 rtbd r0, 3f
Michal Simek23575482009-08-24 13:26:04 +0200325 nop
3263:
Michal Simekb1d70c62010-01-22 10:24:06 +0100327 lwi r11, CURRENT_TASK, TS_THREAD_INFO /* get thread info */
Michal Simek23575482009-08-24 13:26:04 +0200328 lwi r11, r11, TI_FLAGS /* get flags in thread info */
329 andi r11, r11, _TIF_WORK_SYSCALL_MASK
330 beqi r11, 4f
331
332 addik r3, r0, -ENOSYS
Michal Simek6e835572011-01-31 15:10:04 +0100333 swi r3, r1, PT_R3
Michal Simek23575482009-08-24 13:26:04 +0200334 brlid r15, do_syscall_trace_enter
Michal Simek6e835572011-01-31 15:10:04 +0100335 addik r5, r1, PT_R0
Michal Simek23575482009-08-24 13:26:04 +0200336
337 # do_syscall_trace_enter returns the new syscall nr.
338 addk r12, r0, r3
Michal Simek6e835572011-01-31 15:10:04 +0100339 lwi r5, r1, PT_R5;
340 lwi r6, r1, PT_R6;
341 lwi r7, r1, PT_R7;
342 lwi r8, r1, PT_R8;
343 lwi r9, r1, PT_R9;
344 lwi r10, r1, PT_R10;
Michal Simek23575482009-08-24 13:26:04 +02003454:
346/* Jump to the appropriate function for the system call number in r12
347 * (r12 is not preserved), or return an error if r12 is not valid.
348 * The LP register should point to the location where the called function
349 * should return. [note that MAKE_SYS_CALL uses label 1] */
350 /* See if the system call number is valid */
Michal Simekca545022009-05-26 16:30:21 +0200351 addi r11, r12, -__NR_syscalls;
Michal Simek23575482009-08-24 13:26:04 +0200352 bgei r11,5f;
Michal Simekca545022009-05-26 16:30:21 +0200353 /* Figure out which function to use for this system call. */
354 /* Note Microblaze barrel shift is optional, so don't rely on it */
355 add r12, r12, r12; /* convert num -> ptr */
356 add r12, r12, r12;
357
Michal Simek11d51362009-12-07 08:21:34 +0100358#ifdef DEBUG
Michal Simekd8748e72011-01-31 15:04:43 +0100359 /* Trac syscalls and stored them to syscall_debug_table */
360 /* The first syscall location stores total syscall number */
361 lwi r3, r0, syscall_debug_table
Michal Simekca545022009-05-26 16:30:21 +0200362 addi r3, r3, 1
Michal Simekd8748e72011-01-31 15:04:43 +0100363 swi r3, r0, syscall_debug_table
364 lwi r3, r12, syscall_debug_table
365 addi r3, r3, 1
366 swi r3, r12, syscall_debug_table
Michal Simek11d51362009-12-07 08:21:34 +0100367#endif
Michal Simekca545022009-05-26 16:30:21 +0200368
Michal Simek23575482009-08-24 13:26:04 +0200369 # Find and jump into the syscall handler.
370 lwi r12, r12, sys_call_table
371 /* where the trap should return need -8 to adjust for rtsd r15, 8 */
Michal Simekb9ea77e2010-07-28 12:40:02 +0200372 addi r15, r0, ret_from_trap-8
Michal Simek23575482009-08-24 13:26:04 +0200373 bra r12
374
Michal Simekca545022009-05-26 16:30:21 +0200375 /* The syscall number is invalid, return an error. */
Michal Simek23575482009-08-24 13:26:04 +02003765:
Michal Simek9814cc12010-06-22 18:09:29 +0200377 rtsd r15, 8; /* looks like a normal subroutine return */
Michal Simekca545022009-05-26 16:30:21 +0200378 addi r3, r0, -ENOSYS;
Michal Simekca545022009-05-26 16:30:21 +0200379
Michal Simek23575482009-08-24 13:26:04 +0200380/* Entry point used to return from a syscall/trap */
Michal Simekca545022009-05-26 16:30:21 +0200381/* We re-enable BIP bit before state restore */
382C_ENTRY(ret_from_trap):
Michal Simek6e835572011-01-31 15:10:04 +0100383 swi r3, r1, PT_R3
384 swi r4, r1, PT_R4
Michal Simekb1d70c62010-01-22 10:24:06 +0100385
Michal Simek6e835572011-01-31 15:10:04 +0100386 lwi r11, r1, PT_MODE;
Michal Simek9da63452010-10-22 15:48:58 +1000387/* See if returning to kernel mode, if so, skip resched &c. */
388 bnei r11, 2f;
Michal Simekca545022009-05-26 16:30:21 +0200389 /* We're returning to user mode, so check for various conditions that
390 * trigger rescheduling. */
Michal Simekb1d70c62010-01-22 10:24:06 +0100391 /* FIXME: Restructure all these flag checks. */
392 lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
Michal Simek23575482009-08-24 13:26:04 +0200393 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
394 andi r11, r11, _TIF_WORK_SYSCALL_MASK
395 beqi r11, 1f
396
Michal Simek23575482009-08-24 13:26:04 +0200397 brlid r15, do_syscall_trace_leave
Michal Simek6e835572011-01-31 15:10:04 +0100398 addik r5, r1, PT_R0
Michal Simek23575482009-08-24 13:26:04 +02003991:
Michal Simek23575482009-08-24 13:26:04 +0200400 /* We're returning to user mode, so check for various conditions that
401 * trigger rescheduling. */
Michal Simekb1d70c62010-01-22 10:24:06 +0100402 /* get thread info from current task */
403 lwi r11, CURRENT_TASK, TS_THREAD_INFO;
Michal Simekca545022009-05-26 16:30:21 +0200404 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
405 andi r11, r11, _TIF_NEED_RESCHED;
406 beqi r11, 5f;
407
Michal Simekca545022009-05-26 16:30:21 +0200408 bralid r15, schedule; /* Call scheduler */
409 nop; /* delay slot */
Michal Simekca545022009-05-26 16:30:21 +0200410
411 /* Maybe handle a signal */
Michal Simekb1d70c62010-01-22 10:24:06 +01004125: /* get thread info from current task*/
413 lwi r11, CURRENT_TASK, TS_THREAD_INFO;
Michal Simekca545022009-05-26 16:30:21 +0200414 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
Al Viro969a9612012-04-24 02:03:06 -0400415 andi r11, r11, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME;
Michal Simekca545022009-05-26 16:30:21 +0200416 beqi r11, 1f; /* Signals to handle, handle them */
417
Michal Simek6e835572011-01-31 15:10:04 +0100418 addik r5, r1, 0; /* Arg 1: struct pt_regs *regs */
Al Viro969a9612012-04-24 02:03:06 -0400419 bralid r15, do_notify_resume; /* Handle any signals */
Al Viro83140192012-04-24 02:21:18 -0400420 addi r6, r0, 1; /* Arg 2: int in_syscall */
Michal Simekb1d70c62010-01-22 10:24:06 +0100421
422/* Finally, return to user state. */
Michal Simek96014cc2010-06-22 14:05:43 +02004231: set_bip; /* Ints masked for state restore */
Michal Simek8633beb2010-02-22 13:24:43 +0100424 swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */
Michal Simekca545022009-05-26 16:30:21 +0200425 VM_OFF;
426 tophys(r1,r1);
427 RESTORE_REGS;
Michal Simek6e835572011-01-31 15:10:04 +0100428 addik r1, r1, PT_SIZE /* Clean up stack space. */
Michal Simekca545022009-05-26 16:30:21 +0200429 lwi r1, r1, PT_R1 - PT_SIZE;/* Restore user stack pointer. */
Michal Simek9da63452010-10-22 15:48:58 +1000430 bri 6f;
431
432/* Return to kernel state. */
4332: set_bip; /* Ints masked for state restore */
434 VM_OFF;
435 tophys(r1,r1);
436 RESTORE_REGS;
Michal Simek6e835572011-01-31 15:10:04 +0100437 addik r1, r1, PT_SIZE /* Clean up stack space. */
Michal Simek9da63452010-10-22 15:48:58 +1000438 tovirt(r1,r1);
4396:
Michal Simekca545022009-05-26 16:30:21 +0200440TRAP_return: /* Make global symbol for debugging */
441 rtbd r14, 0; /* Instructions to return from an IRQ */
442 nop;
443
444
445/* These syscalls need access to the struct pt_regs on the stack, so we
446 implement them in assembly (they're basically all wrappers anyway). */
447
448C_ENTRY(sys_fork_wrapper):
449 addi r5, r0, SIGCHLD /* Arg 0: flags */
Michal Simek6e835572011-01-31 15:10:04 +0100450 lwi r6, r1, PT_R1 /* Arg 1: child SP (use parent's) */
451 addik r7, r1, 0 /* Arg 2: parent context */
Michal Simek5dbeaad2011-12-22 14:57:13 +0100452 add r8, r0, r0 /* Arg 3: (unused) */
Michal Simekca545022009-05-26 16:30:21 +0200453 add r9, r0, r0; /* Arg 4: (unused) */
Michal Simekca545022009-05-26 16:30:21 +0200454 brid do_fork /* Do real work (tail-call) */
Michal Simek9814cc12010-06-22 18:09:29 +0200455 add r10, r0, r0; /* Arg 5: (unused) */
Michal Simekca545022009-05-26 16:30:21 +0200456
457/* This the initial entry point for a new child thread, with an appropriate
458 stack in place that makes it look the the child is in the middle of an
459 syscall. This function is actually `returned to' from switch_thread
460 (copy_thread makes ret_from_fork the return address in each new thread's
461 saved context). */
462C_ENTRY(ret_from_fork):
463 bralid r15, schedule_tail; /* ...which is schedule_tail's arg */
Michal Simekfd11ff72012-10-09 09:32:32 +0200464 add r5, r3, r0; /* switch_thread returns the prev task */
Michal Simekca545022009-05-26 16:30:21 +0200465 /* ( in the delay slot ) */
Michal Simekca545022009-05-26 16:30:21 +0200466 brid ret_from_trap; /* Do normal trap return */
Michal Simek9814cc12010-06-22 18:09:29 +0200467 add r3, r0, r0; /* Child's fork call should return 0. */
Michal Simekca545022009-05-26 16:30:21 +0200468
Al Viro23192952012-10-06 13:52:37 -0400469C_ENTRY(ret_from_kernel_thread):
470 bralid r15, schedule_tail; /* ...which is schedule_tail's arg */
471 add r5, r3, r0; /* switch_thread returns the prev task */
472 /* ( in the delay slot ) */
473 brald r15, r20 /* fn was left in r20 */
474 addk r5, r0, r19 /* ... and argument - in r19 */
Al Viro99c59f62012-10-10 11:52:44 -0400475 brid ret_from_trap
476 add r3, r0, r0
Al Viro23192952012-10-06 13:52:37 -0400477
Arnd Bergmanne5135882009-06-18 19:55:30 +0200478C_ENTRY(sys_vfork):
479 brid microblaze_vfork /* Do real work (tail-call) */
Michal Simek6e835572011-01-31 15:10:04 +0100480 addik r5, r1, 0
Michal Simekca545022009-05-26 16:30:21 +0200481
Arnd Bergmanne5135882009-06-18 19:55:30 +0200482C_ENTRY(sys_clone):
Michal Simekca545022009-05-26 16:30:21 +0200483 bnei r6, 1f; /* See if child SP arg (arg 1) is 0. */
Michal Simek6e835572011-01-31 15:10:04 +0100484 lwi r6, r1, PT_R1; /* If so, use paret's stack ptr */
4851: addik r7, r1, 0; /* Arg 2: parent context */
Edgar E. Iglesias8d95e122012-02-24 14:52:26 +1000486 lwi r9, r1, PT_R8; /* parent tid. */
487 lwi r10, r1, PT_R9; /* child tid. */
488 /* do_fork will pick up TLS from regs->r10. */
Michal Simekb9ea77e2010-07-28 12:40:02 +0200489 brid do_fork /* Do real work (tail-call) */
Edgar E. Iglesias8d95e122012-02-24 14:52:26 +1000490 add r8, r0, r0; /* Arg 3: (unused) */
Michal Simekca545022009-05-26 16:30:21 +0200491
Arnd Bergmanne5135882009-06-18 19:55:30 +0200492C_ENTRY(sys_execve):
Arnd Bergmanne5135882009-06-18 19:55:30 +0200493 brid microblaze_execve; /* Do real work (tail-call).*/
Michal Simek6e835572011-01-31 15:10:04 +0100494 addik r8, r1, 0; /* add user context as 4th arg */
Michal Simekca545022009-05-26 16:30:21 +0200495
Michal Simekca545022009-05-26 16:30:21 +0200496C_ENTRY(sys_rt_sigreturn_wrapper):
Michal Simek791d0a12010-08-06 10:36:02 +0200497 brid sys_rt_sigreturn /* Do real work */
Michal Simek6e835572011-01-31 15:10:04 +0100498 addik r5, r1, 0; /* add user context as 1st arg */
Michal Simekca545022009-05-26 16:30:21 +0200499
500/*
501 * HW EXCEPTION rutine start
502 */
Michal Simekca545022009-05-26 16:30:21 +0200503C_ENTRY(full_exception_trap):
Michal Simekca545022009-05-26 16:30:21 +0200504 /* adjust exception address for privileged instruction
505 * for finding where is it */
506 addik r17, r17, -4
507 SAVE_STATE /* Save registers */
Michal Simek06a54602010-06-22 16:22:01 +0200508 /* PC, before IRQ/trap - this is one instruction above */
Michal Simek6e835572011-01-31 15:10:04 +0100509 swi r17, r1, PT_PC;
Michal Simek06a54602010-06-22 16:22:01 +0200510 tovirt(r1,r1)
Michal Simekca545022009-05-26 16:30:21 +0200511 /* FIXME this can be store directly in PT_ESR reg.
512 * I tested it but there is a fault */
513 /* where the trap should return need -8 to adjust for rtsd r15, 8 */
Michal Simekb9ea77e2010-07-28 12:40:02 +0200514 addik r15, r0, ret_from_exc - 8
Michal Simekca545022009-05-26 16:30:21 +0200515 mfs r6, resr
Michal Simekca545022009-05-26 16:30:21 +0200516 mfs r7, rfsr; /* save FSR */
Michal Simek131e4e92009-09-28 08:50:53 +0200517 mts rfsr, r0; /* Clear sticky fsr */
Michal Simekc318d482010-06-22 16:25:31 +0200518 rted r0, full_exception
Michal Simek6e835572011-01-31 15:10:04 +0100519 addik r5, r1, 0 /* parameter struct pt_regs * regs */
Michal Simekca545022009-05-26 16:30:21 +0200520
521/*
522 * Unaligned data trap.
523 *
524 * Unaligned data trap last on 4k page is handled here.
525 *
526 * Trap entered via exception, so EE bit is set, and interrupts
527 * are masked. This is nice, means we don't have to CLI before state save
528 *
529 * The assembler routine is in "arch/microblaze/kernel/hw_exception_handler.S"
530 */
531C_ENTRY(unaligned_data_trap):
Michal Simek8b110d12010-06-17 16:03:05 +0200532 /* MS: I have to save r11 value and then restore it because
533 * set_bit, clear_eip, set_ee use r11 as temp register if MSR
534 * instructions are not used. We don't need to do if MSR instructions
535 * are used and they use r0 instead of r11.
536 * I am using ENTRY_SP which should be primary used only for stack
537 * pointer saving. */
538 swi r11, r0, TOPHYS(PER_CPU(ENTRY_SP));
539 set_bip; /* equalize initial state for all possible entries */
540 clear_eip;
541 set_ee;
542 lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP));
Michal Simekca545022009-05-26 16:30:21 +0200543 SAVE_STATE /* Save registers.*/
Michal Simek06a54602010-06-22 16:22:01 +0200544 /* PC, before IRQ/trap - this is one instruction above */
Michal Simek6e835572011-01-31 15:10:04 +0100545 swi r17, r1, PT_PC;
Michal Simek06a54602010-06-22 16:22:01 +0200546 tovirt(r1,r1)
Michal Simekca545022009-05-26 16:30:21 +0200547 /* where the trap should return need -8 to adjust for rtsd r15, 8 */
Michal Simekb9ea77e2010-07-28 12:40:02 +0200548 addik r15, r0, ret_from_exc-8
Michal Simekca545022009-05-26 16:30:21 +0200549 mfs r3, resr /* ESR */
Michal Simekca545022009-05-26 16:30:21 +0200550 mfs r4, rear /* EAR */
Michal Simekc318d482010-06-22 16:25:31 +0200551 rtbd r0, _unaligned_data_exception
Michal Simek6e835572011-01-31 15:10:04 +0100552 addik r7, r1, 0 /* parameter struct pt_regs * regs */
Michal Simekca545022009-05-26 16:30:21 +0200553
554/*
555 * Page fault traps.
556 *
557 * If the real exception handler (from hw_exception_handler.S) didn't find
558 * the mapping for the process, then we're thrown here to handle such situation.
559 *
560 * Trap entered via exceptions, so EE bit is set, and interrupts
561 * are masked. This is nice, means we don't have to CLI before state save
562 *
563 * Build a standard exception frame for TLB Access errors. All TLB exceptions
564 * will bail out to this point if they can't resolve the lightweight TLB fault.
565 *
566 * The C function called is in "arch/microblaze/mm/fault.c", declared as:
567 * void do_page_fault(struct pt_regs *regs,
568 * unsigned long address,
569 * unsigned long error_code)
570 */
571/* data and intruction trap - which is choose is resolved int fault.c */
572C_ENTRY(page_fault_data_trap):
Michal Simekca545022009-05-26 16:30:21 +0200573 SAVE_STATE /* Save registers.*/
Michal Simek06a54602010-06-22 16:22:01 +0200574 /* PC, before IRQ/trap - this is one instruction above */
Michal Simek6e835572011-01-31 15:10:04 +0100575 swi r17, r1, PT_PC;
Michal Simek06a54602010-06-22 16:22:01 +0200576 tovirt(r1,r1)
Michal Simekca545022009-05-26 16:30:21 +0200577 /* where the trap should return need -8 to adjust for rtsd r15, 8 */
Michal Simekb9ea77e2010-07-28 12:40:02 +0200578 addik r15, r0, ret_from_exc-8
Michal Simekca545022009-05-26 16:30:21 +0200579 mfs r6, rear /* parameter unsigned long address */
Michal Simekca545022009-05-26 16:30:21 +0200580 mfs r7, resr /* parameter unsigned long error_code */
Michal Simekc318d482010-06-22 16:25:31 +0200581 rted r0, do_page_fault
Michal Simek6e835572011-01-31 15:10:04 +0100582 addik r5, r1, 0 /* parameter struct pt_regs * regs */
Michal Simekca545022009-05-26 16:30:21 +0200583
584C_ENTRY(page_fault_instr_trap):
Michal Simekca545022009-05-26 16:30:21 +0200585 SAVE_STATE /* Save registers.*/
Michal Simek06a54602010-06-22 16:22:01 +0200586 /* PC, before IRQ/trap - this is one instruction above */
Michal Simek6e835572011-01-31 15:10:04 +0100587 swi r17, r1, PT_PC;
Michal Simek06a54602010-06-22 16:22:01 +0200588 tovirt(r1,r1)
Michal Simekca545022009-05-26 16:30:21 +0200589 /* where the trap should return need -8 to adjust for rtsd r15, 8 */
Michal Simekb9ea77e2010-07-28 12:40:02 +0200590 addik r15, r0, ret_from_exc-8
Michal Simekca545022009-05-26 16:30:21 +0200591 mfs r6, rear /* parameter unsigned long address */
Michal Simekca545022009-05-26 16:30:21 +0200592 ori r7, r0, 0 /* parameter unsigned long error_code */
Michal Simek9814cc12010-06-22 18:09:29 +0200593 rted r0, do_page_fault
Michal Simek6e835572011-01-31 15:10:04 +0100594 addik r5, r1, 0 /* parameter struct pt_regs * regs */
Michal Simekca545022009-05-26 16:30:21 +0200595
596/* Entry point used to return from an exception. */
597C_ENTRY(ret_from_exc):
Michal Simek6e835572011-01-31 15:10:04 +0100598 lwi r11, r1, PT_MODE;
Michal Simekca545022009-05-26 16:30:21 +0200599 bnei r11, 2f; /* See if returning to kernel mode, */
600 /* ... if so, skip resched &c. */
601
602 /* We're returning to user mode, so check for various conditions that
603 trigger rescheduling. */
Michal Simekb1d70c62010-01-22 10:24:06 +0100604 lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
Michal Simekca545022009-05-26 16:30:21 +0200605 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
606 andi r11, r11, _TIF_NEED_RESCHED;
607 beqi r11, 5f;
608
609/* Call the scheduler before returning from a syscall/trap. */
610 bralid r15, schedule; /* Call scheduler */
611 nop; /* delay slot */
612
613 /* Maybe handle a signal */
Michal Simekb1d70c62010-01-22 10:24:06 +01006145: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
Michal Simekca545022009-05-26 16:30:21 +0200615 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
Al Viro969a9612012-04-24 02:03:06 -0400616 andi r11, r11, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME;
Michal Simekca545022009-05-26 16:30:21 +0200617 beqi r11, 1f; /* Signals to handle, handle them */
618
619 /*
620 * Handle a signal return; Pending signals should be in r18.
621 *
622 * Not all registers are saved by the normal trap/interrupt entry
623 * points (for instance, call-saved registers (because the normal
624 * C-compiler calling sequence in the kernel makes sure they're
625 * preserved), and call-clobbered registers in the case of
626 * traps), but signal handlers may want to examine or change the
627 * complete register state. Here we save anything not saved by
628 * the normal entry sequence, so that it may be safely restored
Al Viro969a9612012-04-24 02:03:06 -0400629 * (in a possibly modified form) after do_notify_resume returns. */
Michal Simek6e835572011-01-31 15:10:04 +0100630 addik r5, r1, 0; /* Arg 1: struct pt_regs *regs */
Al Viro969a9612012-04-24 02:03:06 -0400631 bralid r15, do_notify_resume; /* Handle any signals */
Al Viro83140192012-04-24 02:21:18 -0400632 addi r6, r0, 0; /* Arg 2: int in_syscall */
Michal Simekca545022009-05-26 16:30:21 +0200633
634/* Finally, return to user state. */
Michal Simek96014cc2010-06-22 14:05:43 +02006351: set_bip; /* Ints masked for state restore */
Michal Simek8633beb2010-02-22 13:24:43 +0100636 swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */
Michal Simekca545022009-05-26 16:30:21 +0200637 VM_OFF;
638 tophys(r1,r1);
639
Michal Simekca545022009-05-26 16:30:21 +0200640 RESTORE_REGS;
Michal Simek6e835572011-01-31 15:10:04 +0100641 addik r1, r1, PT_SIZE /* Clean up stack space. */
Michal Simekca545022009-05-26 16:30:21 +0200642
643 lwi r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer. */
644 bri 6f;
645/* Return to kernel state. */
Michal Simek96014cc2010-06-22 14:05:43 +02006462: set_bip; /* Ints masked for state restore */
647 VM_OFF;
Michal Simekca545022009-05-26 16:30:21 +0200648 tophys(r1,r1);
Michal Simekca545022009-05-26 16:30:21 +0200649 RESTORE_REGS;
Michal Simek6e835572011-01-31 15:10:04 +0100650 addik r1, r1, PT_SIZE /* Clean up stack space. */
Michal Simekca545022009-05-26 16:30:21 +0200651
652 tovirt(r1,r1);
6536:
654EXC_return: /* Make global symbol for debugging */
655 rtbd r14, 0; /* Instructions to return from an IRQ */
656 nop;
657
658/*
659 * HW EXCEPTION rutine end
660 */
661
662/*
663 * Hardware maskable interrupts.
664 *
665 * The stack-pointer (r1) should have already been saved to the memory
666 * location PER_CPU(ENTRY_SP).
667 */
668C_ENTRY(_interrupt):
669/* MS: we are in physical address */
670/* Save registers, switch to proper stack, convert SP to virtual.*/
671 swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP))
Michal Simekca545022009-05-26 16:30:21 +0200672 /* MS: See if already in kernel mode. */
Michal Simek653e4472010-06-22 14:51:45 +0200673 mfs r1, rmsr
Michal Simek5c0d72b2010-06-22 14:00:12 +0200674 nop
Michal Simek653e4472010-06-22 14:51:45 +0200675 andi r1, r1, MSR_UMS
676 bnei r1, 1f
Michal Simekca545022009-05-26 16:30:21 +0200677
678/* Kernel-mode state save. */
Michal Simek653e4472010-06-22 14:51:45 +0200679 lwi r1, r0, TOPHYS(PER_CPU(ENTRY_SP))
680 tophys(r1,r1); /* MS: I have in r1 physical address where stack is */
Michal Simekca545022009-05-26 16:30:21 +0200681 /* save registers */
682/* MS: Make room on the stack -> activation record */
Michal Simek6e835572011-01-31 15:10:04 +0100683 addik r1, r1, -PT_SIZE;
Michal Simekca545022009-05-26 16:30:21 +0200684 SAVE_REGS
Michal Simekca545022009-05-26 16:30:21 +0200685 brid 2f;
Michal Simek6e835572011-01-31 15:10:04 +0100686 swi r1, r1, PT_MODE; /* 0 - user mode, 1 - kernel mode */
Michal Simekca545022009-05-26 16:30:21 +02006871:
688/* User-mode state save. */
Michal Simekca545022009-05-26 16:30:21 +0200689 /* MS: get the saved current */
690 lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE));
691 tophys(r1,r1);
692 lwi r1, r1, TS_THREAD_INFO;
693 addik r1, r1, THREAD_SIZE;
694 tophys(r1,r1);
695 /* save registers */
Michal Simek6e835572011-01-31 15:10:04 +0100696 addik r1, r1, -PT_SIZE;
Michal Simekca545022009-05-26 16:30:21 +0200697 SAVE_REGS
698 /* calculate mode */
Michal Simek6e835572011-01-31 15:10:04 +0100699 swi r0, r1, PT_MODE;
Michal Simekca545022009-05-26 16:30:21 +0200700 lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP));
Michal Simek6e835572011-01-31 15:10:04 +0100701 swi r11, r1, PT_R1;
Michal Simek80c5ff62010-06-22 18:50:31 +0200702 clear_ums;
Michal Simekca545022009-05-26 16:30:21 +02007032:
Michal Simekb1d70c62010-01-22 10:24:06 +0100704 lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));
Michal Simekca545022009-05-26 16:30:21 +0200705 tovirt(r1,r1)
Michal Simekb9ea77e2010-07-28 12:40:02 +0200706 addik r15, r0, irq_call;
Michal Simek80c5ff62010-06-22 18:50:31 +0200707irq_call:rtbd r0, do_IRQ;
Michal Simek6e835572011-01-31 15:10:04 +0100708 addik r5, r1, 0;
Michal Simekca545022009-05-26 16:30:21 +0200709
710/* MS: we are in virtual mode */
711ret_from_irq:
Michal Simek6e835572011-01-31 15:10:04 +0100712 lwi r11, r1, PT_MODE;
Michal Simekca545022009-05-26 16:30:21 +0200713 bnei r11, 2f;
714
Michal Simekb1d70c62010-01-22 10:24:06 +0100715 lwi r11, CURRENT_TASK, TS_THREAD_INFO;
Michal Simekca545022009-05-26 16:30:21 +0200716 lwi r11, r11, TI_FLAGS; /* MS: get flags from thread info */
717 andi r11, r11, _TIF_NEED_RESCHED;
718 beqi r11, 5f
719 bralid r15, schedule;
720 nop; /* delay slot */
721
722 /* Maybe handle a signal */
Michal Simekb1d70c62010-01-22 10:24:06 +01007235: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* MS: get thread info */
Michal Simekca545022009-05-26 16:30:21 +0200724 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
Al Viro969a9612012-04-24 02:03:06 -0400725 andi r11, r11, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME;
Michal Simekca545022009-05-26 16:30:21 +0200726 beqid r11, no_intr_resched
727/* Handle a signal return; Pending signals should be in r18. */
Michal Simek6e835572011-01-31 15:10:04 +0100728 addik r5, r1, 0; /* Arg 1: struct pt_regs *regs */
Al Viro969a9612012-04-24 02:03:06 -0400729 bralid r15, do_notify_resume; /* Handle any signals */
Al Viro83140192012-04-24 02:21:18 -0400730 addi r6, r0, 0; /* Arg 2: int in_syscall */
Michal Simekca545022009-05-26 16:30:21 +0200731
732/* Finally, return to user state. */
733no_intr_resched:
734 /* Disable interrupts, we are now committed to the state restore */
735 disable_irq
Michal Simek8633beb2010-02-22 13:24:43 +0100736 swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE);
Michal Simekca545022009-05-26 16:30:21 +0200737 VM_OFF;
738 tophys(r1,r1);
Michal Simekca545022009-05-26 16:30:21 +0200739 RESTORE_REGS
Michal Simek6e835572011-01-31 15:10:04 +0100740 addik r1, r1, PT_SIZE /* MS: Clean up stack space. */
Michal Simekca545022009-05-26 16:30:21 +0200741 lwi r1, r1, PT_R1 - PT_SIZE;
742 bri 6f;
743/* MS: Return to kernel state. */
Michal Simek77753792010-01-12 09:55:10 +01007442:
745#ifdef CONFIG_PREEMPT
Michal Simekb1d70c62010-01-22 10:24:06 +0100746 lwi r11, CURRENT_TASK, TS_THREAD_INFO;
Michal Simek77753792010-01-12 09:55:10 +0100747 /* MS: get preempt_count from thread info */
748 lwi r5, r11, TI_PREEMPT_COUNT;
749 bgti r5, restore;
750
751 lwi r5, r11, TI_FLAGS; /* get flags in thread info */
752 andi r5, r5, _TIF_NEED_RESCHED;
753 beqi r5, restore /* if zero jump over */
754
755preempt:
756 /* interrupts are off that's why I am calling preempt_chedule_irq */
757 bralid r15, preempt_schedule_irq
758 nop
Michal Simekb1d70c62010-01-22 10:24:06 +0100759 lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
Michal Simek77753792010-01-12 09:55:10 +0100760 lwi r5, r11, TI_FLAGS; /* get flags in thread info */
761 andi r5, r5, _TIF_NEED_RESCHED;
762 bnei r5, preempt /* if non zero jump to resched */
763restore:
764#endif
765 VM_OFF /* MS: turn off MMU */
Michal Simekca545022009-05-26 16:30:21 +0200766 tophys(r1,r1)
Michal Simekca545022009-05-26 16:30:21 +0200767 RESTORE_REGS
Michal Simek6e835572011-01-31 15:10:04 +0100768 addik r1, r1, PT_SIZE /* MS: Clean up stack space. */
Michal Simekca545022009-05-26 16:30:21 +0200769 tovirt(r1,r1);
7706:
771IRQ_return: /* MS: Make global symbol for debugging */
772 rtid r14, 0
773 nop
774
775/*
Michal Simek2d5973c2010-08-03 11:45:08 +0200776 * Debug trap for KGDB. Enter to _debug_exception by brki r16, 0x18
777 * and call handling function with saved pt_regs
Michal Simekca545022009-05-26 16:30:21 +0200778 */
779C_ENTRY(_debug_exception):
780 /* BIP bit is set on entry, no interrupts can occur */
781 swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP))
782
Michal Simek653e4472010-06-22 14:51:45 +0200783 mfs r1, rmsr
Michal Simek5c0d72b2010-06-22 14:00:12 +0200784 nop
Michal Simek653e4472010-06-22 14:51:45 +0200785 andi r1, r1, MSR_UMS
786 bnei r1, 1f
Michal Simek2d5973c2010-08-03 11:45:08 +0200787/* MS: Kernel-mode state save - kgdb */
Michal Simek653e4472010-06-22 14:51:45 +0200788 lwi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/
Michal Simekca545022009-05-26 16:30:21 +0200789
Michal Simek2d5973c2010-08-03 11:45:08 +0200790 /* BIP bit is set on entry, no interrupts can occur */
Michal Simek6e835572011-01-31 15:10:04 +0100791 addik r1, r1, CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START - PT_SIZE;
Michal Simekca545022009-05-26 16:30:21 +0200792 SAVE_REGS;
Michal Simek2d5973c2010-08-03 11:45:08 +0200793 /* save all regs to pt_reg structure */
Michal Simek6e835572011-01-31 15:10:04 +0100794 swi r0, r1, PT_R0; /* R0 must be saved too */
795 swi r14, r1, PT_R14 /* rewrite saved R14 value */
796 swi r16, r1, PT_PC; /* PC and r16 are the same */
Michal Simek2d5973c2010-08-03 11:45:08 +0200797 /* save special purpose registers to pt_regs */
798 mfs r11, rear;
Michal Simek6e835572011-01-31 15:10:04 +0100799 swi r11, r1, PT_EAR;
Michal Simek2d5973c2010-08-03 11:45:08 +0200800 mfs r11, resr;
Michal Simek6e835572011-01-31 15:10:04 +0100801 swi r11, r1, PT_ESR;
Michal Simek2d5973c2010-08-03 11:45:08 +0200802 mfs r11, rfsr;
Michal Simek6e835572011-01-31 15:10:04 +0100803 swi r11, r1, PT_FSR;
Michal Simekca545022009-05-26 16:30:21 +0200804
Michal Simek2d5973c2010-08-03 11:45:08 +0200805 /* stack pointer is in physical address at it is decrease
Michal Simek6e835572011-01-31 15:10:04 +0100806 * by PT_SIZE but we need to get correct R1 value */
807 addik r11, r1, CONFIG_KERNEL_START - CONFIG_KERNEL_BASE_ADDR + PT_SIZE;
808 swi r11, r1, PT_R1
Michal Simek2d5973c2010-08-03 11:45:08 +0200809 /* MS: r31 - current pointer isn't changed */
810 tovirt(r1,r1)
811#ifdef CONFIG_KGDB
Michal Simek6e835572011-01-31 15:10:04 +0100812 addi r5, r1, 0 /* pass pt_reg address as the first arg */
Michal Simekcd341572011-02-01 09:00:57 +0100813 addik r15, r0, dbtrap_call; /* return address */
Michal Simek2d5973c2010-08-03 11:45:08 +0200814 rtbd r0, microblaze_kgdb_break
815 nop;
816#endif
817 /* MS: Place handler for brki from kernel space if KGDB is OFF.
818 * It is very unlikely that another brki instruction is called. */
819 bri 0
820
821/* MS: User-mode state save - gdb */
8221: lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */
Michal Simekca545022009-05-26 16:30:21 +0200823 tophys(r1,r1);
824 lwi r1, r1, TS_THREAD_INFO; /* get the thread info */
825 addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */
826 tophys(r1,r1);
827
Michal Simek6e835572011-01-31 15:10:04 +0100828 addik r1, r1, -PT_SIZE; /* Make room on the stack. */
Michal Simekca545022009-05-26 16:30:21 +0200829 SAVE_REGS;
Michal Simek6e835572011-01-31 15:10:04 +0100830 swi r16, r1, PT_PC; /* Save LP */
831 swi r0, r1, PT_MODE; /* Was in user-mode. */
Michal Simekca545022009-05-26 16:30:21 +0200832 lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP));
Michal Simek6e835572011-01-31 15:10:04 +0100833 swi r11, r1, PT_R1; /* Store user SP. */
Michal Simek2d5973c2010-08-03 11:45:08 +0200834 lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));
Michal Simekca545022009-05-26 16:30:21 +0200835 tovirt(r1,r1)
Michal Simek06b28642010-06-22 15:25:24 +0200836 set_vms;
Michal Simek6e835572011-01-31 15:10:04 +0100837 addik r5, r1, 0;
Michal Simekb9ea77e2010-07-28 12:40:02 +0200838 addik r15, r0, dbtrap_call;
Michal Simek2d5973c2010-08-03 11:45:08 +0200839dbtrap_call: /* Return point for kernel/user entry + 8 because of rtsd r15, 8 */
Michal Simek751f1602010-08-03 11:26:51 +0200840 rtbd r0, sw_exception
841 nop
Michal Simekca545022009-05-26 16:30:21 +0200842
Michal Simek2d5973c2010-08-03 11:45:08 +0200843 /* MS: The first instruction for the second part of the gdb/kgdb */
844 set_bip; /* Ints masked for state restore */
Michal Simek6e835572011-01-31 15:10:04 +0100845 lwi r11, r1, PT_MODE;
Michal Simekca545022009-05-26 16:30:21 +0200846 bnei r11, 2f;
Michal Simek2d5973c2010-08-03 11:45:08 +0200847/* MS: Return to user space - gdb */
Michal Simekca545022009-05-26 16:30:21 +0200848 /* Get current task ptr into r11 */
Michal Simekb1d70c62010-01-22 10:24:06 +0100849 lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
Michal Simekca545022009-05-26 16:30:21 +0200850 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
851 andi r11, r11, _TIF_NEED_RESCHED;
852 beqi r11, 5f;
853
Michal Simek2d5973c2010-08-03 11:45:08 +0200854 /* Call the scheduler before returning from a syscall/trap. */
Michal Simekca545022009-05-26 16:30:21 +0200855 bralid r15, schedule; /* Call scheduler */
856 nop; /* delay slot */
Michal Simekca545022009-05-26 16:30:21 +0200857
858 /* Maybe handle a signal */
Michal Simekb1d70c62010-01-22 10:24:06 +01008595: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */
Michal Simekca545022009-05-26 16:30:21 +0200860 lwi r11, r11, TI_FLAGS; /* get flags in thread info */
Al Viro969a9612012-04-24 02:03:06 -0400861 andi r11, r11, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME;
Michal Simekca545022009-05-26 16:30:21 +0200862 beqi r11, 1f; /* Signals to handle, handle them */
863
Michal Simek6e835572011-01-31 15:10:04 +0100864 addik r5, r1, 0; /* Arg 1: struct pt_regs *regs */
Al Viro969a9612012-04-24 02:03:06 -0400865 bralid r15, do_notify_resume; /* Handle any signals */
Al Viro83140192012-04-24 02:21:18 -0400866 addi r6, r0, 0; /* Arg 2: int in_syscall */
Michal Simekca545022009-05-26 16:30:21 +0200867
Michal Simekca545022009-05-26 16:30:21 +0200868/* Finally, return to user state. */
Michal Simek2d5973c2010-08-03 11:45:08 +02008691: swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */
Michal Simekca545022009-05-26 16:30:21 +0200870 VM_OFF;
871 tophys(r1,r1);
Michal Simek2d5973c2010-08-03 11:45:08 +0200872 /* MS: Restore all regs */
Michal Simekca545022009-05-26 16:30:21 +0200873 RESTORE_REGS
Michal Simek6e835572011-01-31 15:10:04 +0100874 addik r1, r1, PT_SIZE /* Clean up stack space */
Michal Simek2d5973c2010-08-03 11:45:08 +0200875 lwi r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer */
876DBTRAP_return_user: /* MS: Make global symbol for debugging */
877 rtbd r16, 0; /* MS: Instructions to return from a debug trap */
878 nop;
Michal Simekca545022009-05-26 16:30:21 +0200879
Michal Simek2d5973c2010-08-03 11:45:08 +0200880/* MS: Return to kernel state - kgdb */
Michal Simekca545022009-05-26 16:30:21 +02008812: VM_OFF;
882 tophys(r1,r1);
Michal Simek2d5973c2010-08-03 11:45:08 +0200883 /* MS: Restore all regs */
Michal Simekca545022009-05-26 16:30:21 +0200884 RESTORE_REGS
Michal Simek6e835572011-01-31 15:10:04 +0100885 lwi r14, r1, PT_R14;
886 lwi r16, r1, PT_PC;
887 addik r1, r1, PT_SIZE; /* MS: Clean up stack space */
Michal Simekca545022009-05-26 16:30:21 +0200888 tovirt(r1,r1);
Michal Simek2d5973c2010-08-03 11:45:08 +0200889DBTRAP_return_kernel: /* MS: Make global symbol for debugging */
890 rtbd r16, 0; /* MS: Instructions to return from a debug trap */
Michal Simekca545022009-05-26 16:30:21 +0200891 nop;
892
893
Michal Simekca545022009-05-26 16:30:21 +0200894ENTRY(_switch_to)
895 /* prepare return value */
Michal Simekb1d70c62010-01-22 10:24:06 +0100896 addk r3, r0, CURRENT_TASK
Michal Simekca545022009-05-26 16:30:21 +0200897
898 /* save registers in cpu_context */
899 /* use r11 and r12, volatile registers, as temp register */
900 /* give start of cpu_context for previous process */
901 addik r11, r5, TI_CPU_CONTEXT
902 swi r1, r11, CC_R1
903 swi r2, r11, CC_R2
904 /* skip volatile registers.
905 * they are saved on stack when we jumped to _switch_to() */
906 /* dedicated registers */
907 swi r13, r11, CC_R13
908 swi r14, r11, CC_R14
909 swi r15, r11, CC_R15
910 swi r16, r11, CC_R16
911 swi r17, r11, CC_R17
912 swi r18, r11, CC_R18
913 /* save non-volatile registers */
914 swi r19, r11, CC_R19
915 swi r20, r11, CC_R20
916 swi r21, r11, CC_R21
917 swi r22, r11, CC_R22
918 swi r23, r11, CC_R23
919 swi r24, r11, CC_R24
920 swi r25, r11, CC_R25
921 swi r26, r11, CC_R26
922 swi r27, r11, CC_R27
923 swi r28, r11, CC_R28
924 swi r29, r11, CC_R29
925 swi r30, r11, CC_R30
926 /* special purpose registers */
927 mfs r12, rmsr
Michal Simekca545022009-05-26 16:30:21 +0200928 swi r12, r11, CC_MSR
929 mfs r12, rear
Michal Simekca545022009-05-26 16:30:21 +0200930 swi r12, r11, CC_EAR
931 mfs r12, resr
Michal Simekca545022009-05-26 16:30:21 +0200932 swi r12, r11, CC_ESR
933 mfs r12, rfsr
Michal Simekca545022009-05-26 16:30:21 +0200934 swi r12, r11, CC_FSR
935
Michal Simekb1d70c62010-01-22 10:24:06 +0100936 /* update r31, the current-give me pointer to task which will be next */
937 lwi CURRENT_TASK, r6, TI_TASK
Michal Simekca545022009-05-26 16:30:21 +0200938 /* stored it to current_save too */
Michal Simekb1d70c62010-01-22 10:24:06 +0100939 swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE)
Michal Simekca545022009-05-26 16:30:21 +0200940
941 /* get new process' cpu context and restore */
942 /* give me start where start context of next task */
943 addik r11, r6, TI_CPU_CONTEXT
944
945 /* non-volatile registers */
946 lwi r30, r11, CC_R30
947 lwi r29, r11, CC_R29
948 lwi r28, r11, CC_R28
949 lwi r27, r11, CC_R27
950 lwi r26, r11, CC_R26
951 lwi r25, r11, CC_R25
952 lwi r24, r11, CC_R24
953 lwi r23, r11, CC_R23
954 lwi r22, r11, CC_R22
955 lwi r21, r11, CC_R21
956 lwi r20, r11, CC_R20
957 lwi r19, r11, CC_R19
958 /* dedicated registers */
959 lwi r18, r11, CC_R18
960 lwi r17, r11, CC_R17
961 lwi r16, r11, CC_R16
962 lwi r15, r11, CC_R15
963 lwi r14, r11, CC_R14
964 lwi r13, r11, CC_R13
965 /* skip volatile registers */
966 lwi r2, r11, CC_R2
967 lwi r1, r11, CC_R1
968
969 /* special purpose registers */
970 lwi r12, r11, CC_FSR
971 mts rfsr, r12
Michal Simekca545022009-05-26 16:30:21 +0200972 lwi r12, r11, CC_MSR
973 mts rmsr, r12
Michal Simekca545022009-05-26 16:30:21 +0200974
975 rtsd r15, 8
976 nop
977
978ENTRY(_reset)
Michal Simek75743492011-03-10 10:56:21 +0100979 brai 0; /* Jump to reset vector */
Michal Simekca545022009-05-26 16:30:21 +0200980
Michal Simekca545022009-05-26 16:30:21 +0200981 /* These are compiled and loaded into high memory, then
982 * copied into place in mach_early_setup */
983 .section .init.ivt, "ax"
Michal Simek0b9b0202010-11-08 12:37:40 +0100984#if CONFIG_MANUAL_RESET_VECTOR
Michal Simekca545022009-05-26 16:30:21 +0200985 .org 0x0
Michal Simek0b9b0202010-11-08 12:37:40 +0100986 brai CONFIG_MANUAL_RESET_VECTOR
987#endif
Michal Simek626afa32011-03-10 10:51:27 +0100988 .org 0x8
Michal Simekca545022009-05-26 16:30:21 +0200989 brai TOPHYS(_user_exception); /* syscall handler */
Michal Simek626afa32011-03-10 10:51:27 +0100990 .org 0x10
Michal Simekca545022009-05-26 16:30:21 +0200991 brai TOPHYS(_interrupt); /* Interrupt handler */
Michal Simek626afa32011-03-10 10:51:27 +0100992 .org 0x18
Michal Simek751f1602010-08-03 11:26:51 +0200993 brai TOPHYS(_debug_exception); /* debug trap handler */
Michal Simek626afa32011-03-10 10:51:27 +0100994 .org 0x20
Michal Simekca545022009-05-26 16:30:21 +0200995 brai TOPHYS(_hw_exception_handler); /* HW exception handler */
996
Michal Simekca545022009-05-26 16:30:21 +0200997.section .rodata,"a"
998#include "syscall_table.S"
999
1000syscall_table_size=(.-sys_call_table)
1001
Steven J. Magnanice3266c2010-04-27 12:37:54 -05001002type_SYSCALL:
1003 .ascii "SYSCALL\0"
1004type_IRQ:
1005 .ascii "IRQ\0"
1006type_IRQ_PREEMPT:
1007 .ascii "IRQ (PREEMPTED)\0"
1008type_SYSCALL_PREEMPT:
1009 .ascii " SYSCALL (PREEMPTED)\0"
1010
1011 /*
1012 * Trap decoding for stack unwinder
1013 * Tuples are (start addr, end addr, string)
1014 * If return address lies on [start addr, end addr],
1015 * unwinder displays 'string'
1016 */
1017
1018 .align 4
1019.global microblaze_trap_handlers
1020microblaze_trap_handlers:
1021 /* Exact matches come first */
1022 .word ret_from_trap; .word ret_from_trap ; .word type_SYSCALL
1023 .word ret_from_irq ; .word ret_from_irq ; .word type_IRQ
1024 /* Fuzzy matches go here */
1025 .word ret_from_irq ; .word no_intr_resched ; .word type_IRQ_PREEMPT
1026 .word ret_from_trap; .word TRAP_return ; .word type_SYSCALL_PREEMPT
1027 /* End of table */
1028 .word 0 ; .word 0 ; .word 0