Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 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 | |
Michal Simek | 11d5136 | 2009-12-07 08:21:34 +0100 | [diff] [blame] | 34 | #undef DEBUG |
| 35 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 36 | /* The size of a state save frame. */ |
| 37 | #define STATE_SAVE_SIZE (PT_SIZE + STATE_SAVE_ARG_SPACE) |
| 38 | |
| 39 | /* The offset of the struct pt_regs in a `state save frame' on the stack. */ |
| 40 | #define PTO STATE_SAVE_ARG_SPACE /* 24 the space for args */ |
| 41 | |
| 42 | #define C_ENTRY(name) .globl name; .align 4; name |
| 43 | |
| 44 | /* |
| 45 | * Various ways of setting and clearing BIP in flags reg. |
| 46 | * This is mucky, but necessary using microblaze version that |
| 47 | * allows msr ops to write to BIP |
| 48 | */ |
| 49 | #if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR |
| 50 | .macro clear_bip |
| 51 | msrclr r11, MSR_BIP |
| 52 | nop |
| 53 | .endm |
| 54 | |
| 55 | .macro set_bip |
| 56 | msrset r11, MSR_BIP |
| 57 | nop |
| 58 | .endm |
| 59 | |
| 60 | .macro clear_eip |
| 61 | msrclr r11, MSR_EIP |
| 62 | nop |
| 63 | .endm |
| 64 | |
| 65 | .macro set_ee |
| 66 | msrset r11, MSR_EE |
| 67 | nop |
| 68 | .endm |
| 69 | |
| 70 | .macro disable_irq |
| 71 | msrclr r11, MSR_IE |
| 72 | nop |
| 73 | .endm |
| 74 | |
| 75 | .macro enable_irq |
| 76 | msrset r11, MSR_IE |
| 77 | nop |
| 78 | .endm |
| 79 | |
| 80 | .macro set_ums |
| 81 | msrset r11, MSR_UMS |
| 82 | nop |
| 83 | msrclr r11, MSR_VMS |
| 84 | nop |
| 85 | .endm |
| 86 | |
| 87 | .macro set_vms |
| 88 | msrclr r11, MSR_UMS |
| 89 | nop |
| 90 | msrset r11, MSR_VMS |
| 91 | nop |
| 92 | .endm |
| 93 | |
| 94 | .macro clear_vms_ums |
| 95 | msrclr r11, MSR_VMS |
| 96 | nop |
| 97 | msrclr r11, MSR_UMS |
| 98 | nop |
| 99 | .endm |
| 100 | #else |
| 101 | .macro clear_bip |
| 102 | mfs r11, rmsr |
| 103 | nop |
| 104 | andi r11, r11, ~MSR_BIP |
| 105 | mts rmsr, r11 |
| 106 | nop |
| 107 | .endm |
| 108 | |
| 109 | .macro set_bip |
| 110 | mfs r11, rmsr |
| 111 | nop |
| 112 | ori r11, r11, MSR_BIP |
| 113 | mts rmsr, r11 |
| 114 | nop |
| 115 | .endm |
| 116 | |
| 117 | .macro clear_eip |
| 118 | mfs r11, rmsr |
| 119 | nop |
| 120 | andi r11, r11, ~MSR_EIP |
| 121 | mts rmsr, r11 |
| 122 | nop |
| 123 | .endm |
| 124 | |
| 125 | .macro set_ee |
| 126 | mfs r11, rmsr |
| 127 | nop |
| 128 | ori r11, r11, MSR_EE |
| 129 | mts rmsr, r11 |
| 130 | nop |
| 131 | .endm |
| 132 | |
| 133 | .macro disable_irq |
| 134 | mfs r11, rmsr |
| 135 | nop |
| 136 | andi r11, r11, ~MSR_IE |
| 137 | mts rmsr, r11 |
| 138 | nop |
| 139 | .endm |
| 140 | |
| 141 | .macro enable_irq |
| 142 | mfs r11, rmsr |
| 143 | nop |
| 144 | ori r11, r11, MSR_IE |
| 145 | mts rmsr, r11 |
| 146 | nop |
| 147 | .endm |
| 148 | |
| 149 | .macro set_ums |
| 150 | mfs r11, rmsr |
| 151 | nop |
| 152 | ori r11, r11, MSR_VMS |
| 153 | andni r11, r11, MSR_UMS |
| 154 | mts rmsr, r11 |
| 155 | nop |
| 156 | .endm |
| 157 | |
| 158 | .macro set_vms |
| 159 | mfs r11, rmsr |
| 160 | nop |
| 161 | ori r11, r11, MSR_VMS |
| 162 | andni r11, r11, MSR_UMS |
| 163 | mts rmsr, r11 |
| 164 | nop |
| 165 | .endm |
| 166 | |
| 167 | .macro clear_vms_ums |
| 168 | mfs r11, rmsr |
| 169 | nop |
| 170 | andni r11, r11, (MSR_VMS|MSR_UMS) |
| 171 | mts rmsr,r11 |
| 172 | nop |
| 173 | .endm |
| 174 | #endif |
| 175 | |
| 176 | /* Define how to call high-level functions. With MMU, virtual mode must be |
| 177 | * enabled when calling the high-level function. Clobbers R11. |
| 178 | * VM_ON, VM_OFF, DO_JUMP_BIPCLR, DO_CALL |
| 179 | */ |
| 180 | |
| 181 | /* turn on virtual protected mode save */ |
| 182 | #define VM_ON \ |
| 183 | set_ums; \ |
| 184 | rted r0, 2f; \ |
| 185 | 2: nop; |
| 186 | |
| 187 | /* turn off virtual protected mode save and user mode save*/ |
| 188 | #define VM_OFF \ |
| 189 | clear_vms_ums; \ |
| 190 | rted r0, TOPHYS(1f); \ |
| 191 | 1: nop; |
| 192 | |
| 193 | #define SAVE_REGS \ |
| 194 | swi r2, r1, PTO+PT_R2; /* Save SDA */ \ |
| 195 | swi r5, r1, PTO+PT_R5; \ |
| 196 | swi r6, r1, PTO+PT_R6; \ |
| 197 | swi r7, r1, PTO+PT_R7; \ |
| 198 | swi r8, r1, PTO+PT_R8; \ |
| 199 | swi r9, r1, PTO+PT_R9; \ |
| 200 | swi r10, r1, PTO+PT_R10; \ |
| 201 | swi r11, r1, PTO+PT_R11; /* save clobbered regs after rval */\ |
| 202 | swi r12, r1, PTO+PT_R12; \ |
| 203 | swi r13, r1, PTO+PT_R13; /* Save SDA2 */ \ |
| 204 | swi r14, r1, PTO+PT_PC; /* PC, before IRQ/trap */ \ |
| 205 | swi r15, r1, PTO+PT_R15; /* Save LP */ \ |
| 206 | swi r18, r1, PTO+PT_R18; /* Save asm scratch reg */ \ |
| 207 | swi r19, r1, PTO+PT_R19; \ |
| 208 | swi r20, r1, PTO+PT_R20; \ |
| 209 | swi r21, r1, PTO+PT_R21; \ |
| 210 | swi r22, r1, PTO+PT_R22; \ |
| 211 | swi r23, r1, PTO+PT_R23; \ |
| 212 | swi r24, r1, PTO+PT_R24; \ |
| 213 | swi r25, r1, PTO+PT_R25; \ |
| 214 | swi r26, r1, PTO+PT_R26; \ |
| 215 | swi r27, r1, PTO+PT_R27; \ |
| 216 | swi r28, r1, PTO+PT_R28; \ |
| 217 | swi r29, r1, PTO+PT_R29; \ |
| 218 | swi r30, r1, PTO+PT_R30; \ |
| 219 | swi r31, r1, PTO+PT_R31; /* Save current task reg */ \ |
| 220 | mfs r11, rmsr; /* save MSR */ \ |
| 221 | nop; \ |
| 222 | swi r11, r1, PTO+PT_MSR; |
| 223 | |
| 224 | #define RESTORE_REGS \ |
| 225 | lwi r11, r1, PTO+PT_MSR; \ |
| 226 | mts rmsr , r11; \ |
| 227 | nop; \ |
| 228 | lwi r2, r1, PTO+PT_R2; /* restore SDA */ \ |
| 229 | lwi r5, r1, PTO+PT_R5; \ |
| 230 | lwi r6, r1, PTO+PT_R6; \ |
| 231 | lwi r7, r1, PTO+PT_R7; \ |
| 232 | lwi r8, r1, PTO+PT_R8; \ |
| 233 | lwi r9, r1, PTO+PT_R9; \ |
| 234 | lwi r10, r1, PTO+PT_R10; \ |
| 235 | lwi r11, r1, PTO+PT_R11; /* restore clobbered regs after rval */\ |
| 236 | lwi r12, r1, PTO+PT_R12; \ |
| 237 | lwi r13, r1, PTO+PT_R13; /* restore SDA2 */ \ |
| 238 | lwi r14, r1, PTO+PT_PC; /* RESTORE_LINK PC, before IRQ/trap */\ |
| 239 | lwi r15, r1, PTO+PT_R15; /* restore LP */ \ |
| 240 | lwi r18, r1, PTO+PT_R18; /* restore asm scratch reg */ \ |
| 241 | lwi r19, r1, PTO+PT_R19; \ |
| 242 | lwi r20, r1, PTO+PT_R20; \ |
| 243 | lwi r21, r1, PTO+PT_R21; \ |
| 244 | lwi r22, r1, PTO+PT_R22; \ |
| 245 | lwi r23, r1, PTO+PT_R23; \ |
| 246 | lwi r24, r1, PTO+PT_R24; \ |
| 247 | lwi r25, r1, PTO+PT_R25; \ |
| 248 | lwi r26, r1, PTO+PT_R26; \ |
| 249 | lwi r27, r1, PTO+PT_R27; \ |
| 250 | lwi r28, r1, PTO+PT_R28; \ |
| 251 | lwi r29, r1, PTO+PT_R29; \ |
| 252 | lwi r30, r1, PTO+PT_R30; \ |
| 253 | lwi r31, r1, PTO+PT_R31; /* Restore cur task reg */ |
| 254 | |
| 255 | .text |
| 256 | |
| 257 | /* |
| 258 | * User trap. |
| 259 | * |
| 260 | * System calls are handled here. |
| 261 | * |
| 262 | * Syscall protocol: |
| 263 | * Syscall number in r12, args in r5-r10 |
| 264 | * Return value in r3 |
| 265 | * |
| 266 | * Trap entered via brki instruction, so BIP bit is set, and interrupts |
| 267 | * are masked. This is nice, means we don't have to CLI before state save |
| 268 | */ |
| 269 | C_ENTRY(_user_exception): |
| 270 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 271 | addi r14, r14, 4 /* return address is 4 byte after call */ |
| 272 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ |
| 273 | |
| 274 | lwi r11, r0, TOPHYS(PER_CPU(KM));/* See if already in kernel mode.*/ |
| 275 | beqi r11, 1f; /* Jump ahead if coming from user */ |
| 276 | /* Kernel-mode state save. */ |
| 277 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ |
| 278 | tophys(r1,r11); |
| 279 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ |
| 280 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 281 | |
| 282 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
| 283 | SAVE_REGS |
| 284 | |
| 285 | addi r11, r0, 1; /* Was in kernel-mode. */ |
| 286 | swi r11, r1, PTO+PT_MODE; /* pt_regs -> kernel mode */ |
| 287 | brid 2f; |
| 288 | nop; /* Fill delay slot */ |
| 289 | |
| 290 | /* User-mode state save. */ |
| 291 | 1: |
| 292 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 293 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ |
| 294 | tophys(r1,r1); |
| 295 | lwi r1, r1, TS_THREAD_INFO; /* get stack from task_struct */ |
| 296 | /* calculate kernel stack pointer from task struct 8k */ |
| 297 | addik r1, r1, THREAD_SIZE; |
| 298 | tophys(r1,r1); |
| 299 | |
| 300 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
| 301 | SAVE_REGS |
| 302 | |
| 303 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ |
| 304 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); |
| 305 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ |
| 306 | addi r11, r0, 1; |
| 307 | swi r11, r0, TOPHYS(PER_CPU(KM)); /* Now we're in kernel-mode. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 308 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 309 | /* Save away the syscall number. */ |
| 310 | swi r12, r1, PTO+PT_R0; |
| 311 | tovirt(r1,r1) |
| 312 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 313 | /* where the trap should return need -8 to adjust for rtsd r15, 8*/ |
| 314 | /* Jump to the appropriate function for the system call number in r12 |
| 315 | * (r12 is not preserved), or return an error if r12 is not valid. The LP |
| 316 | * register should point to the location where |
| 317 | * the called function should return. [note that MAKE_SYS_CALL uses label 1] */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 318 | |
| 319 | # Step into virtual mode. |
| 320 | set_vms; |
| 321 | addik r11, r0, 3f |
| 322 | rtid r11, 0 |
| 323 | nop |
| 324 | 3: |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 325 | lwi r11, CURRENT_TASK, TS_THREAD_INFO /* get thread info */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 326 | lwi r11, r11, TI_FLAGS /* get flags in thread info */ |
| 327 | andi r11, r11, _TIF_WORK_SYSCALL_MASK |
| 328 | beqi r11, 4f |
| 329 | |
| 330 | addik r3, r0, -ENOSYS |
| 331 | swi r3, r1, PTO + PT_R3 |
| 332 | brlid r15, do_syscall_trace_enter |
| 333 | addik r5, r1, PTO + PT_R0 |
| 334 | |
| 335 | # do_syscall_trace_enter returns the new syscall nr. |
| 336 | addk r12, r0, r3 |
| 337 | lwi r5, r1, PTO+PT_R5; |
| 338 | lwi r6, r1, PTO+PT_R6; |
| 339 | lwi r7, r1, PTO+PT_R7; |
| 340 | lwi r8, r1, PTO+PT_R8; |
| 341 | lwi r9, r1, PTO+PT_R9; |
| 342 | lwi r10, r1, PTO+PT_R10; |
| 343 | 4: |
| 344 | /* Jump to the appropriate function for the system call number in r12 |
| 345 | * (r12 is not preserved), or return an error if r12 is not valid. |
| 346 | * The LP register should point to the location where the called function |
| 347 | * should return. [note that MAKE_SYS_CALL uses label 1] */ |
| 348 | /* See if the system call number is valid */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 349 | addi r11, r12, -__NR_syscalls; |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 350 | bgei r11,5f; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 351 | /* Figure out which function to use for this system call. */ |
| 352 | /* Note Microblaze barrel shift is optional, so don't rely on it */ |
| 353 | add r12, r12, r12; /* convert num -> ptr */ |
| 354 | add r12, r12, r12; |
| 355 | |
Michal Simek | 11d5136 | 2009-12-07 08:21:34 +0100 | [diff] [blame] | 356 | #ifdef DEBUG |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 357 | /* Trac syscalls and stored them to r0_ram */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 358 | lwi r3, r12, 0x400 + r0_ram |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 359 | addi r3, r3, 1 |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 360 | swi r3, r12, 0x400 + r0_ram |
Michal Simek | 11d5136 | 2009-12-07 08:21:34 +0100 | [diff] [blame] | 361 | #endif |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 362 | |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 363 | # Find and jump into the syscall handler. |
| 364 | lwi r12, r12, sys_call_table |
| 365 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 366 | la r15, r0, ret_from_trap-8 |
| 367 | bra r12 |
| 368 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 369 | /* The syscall number is invalid, return an error. */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 370 | 5: |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 371 | addi r3, r0, -ENOSYS; |
| 372 | rtsd r15,8; /* looks like a normal subroutine return */ |
| 373 | or r0, r0, r0 |
| 374 | |
| 375 | |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 376 | /* Entry point used to return from a syscall/trap */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 377 | /* We re-enable BIP bit before state restore */ |
| 378 | C_ENTRY(ret_from_trap): |
| 379 | set_bip; /* Ints masked for state restore*/ |
| 380 | lwi r11, r1, PTO+PT_MODE; |
| 381 | /* See if returning to kernel mode, if so, skip resched &c. */ |
| 382 | bnei r11, 2f; |
| 383 | |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 384 | swi r3, r1, PTO + PT_R3 |
| 385 | swi r4, r1, PTO + PT_R4 |
| 386 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 387 | /* We're returning to user mode, so check for various conditions that |
| 388 | * trigger rescheduling. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 389 | /* FIXME: Restructure all these flag checks. */ |
| 390 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 391 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 392 | andi r11, r11, _TIF_WORK_SYSCALL_MASK |
| 393 | beqi r11, 1f |
| 394 | |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 395 | brlid r15, do_syscall_trace_leave |
| 396 | addik r5, r1, PTO + PT_R0 |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 397 | 1: |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 398 | /* We're returning to user mode, so check for various conditions that |
| 399 | * trigger rescheduling. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 400 | /* get thread info from current task */ |
| 401 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 402 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 403 | andi r11, r11, _TIF_NEED_RESCHED; |
| 404 | beqi r11, 5f; |
| 405 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 406 | bralid r15, schedule; /* Call scheduler */ |
| 407 | nop; /* delay slot */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 408 | |
| 409 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 410 | 5: /* get thread info from current task*/ |
| 411 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 412 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 413 | andi r11, r11, _TIF_SIGPENDING; |
| 414 | beqi r11, 1f; /* Signals to handle, handle them */ |
| 415 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 416 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 417 | addi r7, r0, 1; /* Arg 3: int in_syscall */ |
| 418 | bralid r15, do_signal; /* Handle any signals */ |
Michal Simek | 841d6e8 | 2010-01-22 14:28:36 +0100 | [diff] [blame] | 419 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 420 | |
| 421 | /* Finally, return to user state. */ |
| 422 | 1: |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 423 | lwi r3, r1, PTO + PT_R3; /* restore syscall result */ |
| 424 | lwi r4, r1, PTO + PT_R4; |
| 425 | |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 426 | swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 427 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 428 | VM_OFF; |
| 429 | tophys(r1,r1); |
| 430 | RESTORE_REGS; |
| 431 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 432 | lwi r1, r1, PT_R1 - PT_SIZE;/* Restore user stack pointer. */ |
| 433 | bri 6f; |
| 434 | |
| 435 | /* Return to kernel state. */ |
| 436 | 2: VM_OFF; |
| 437 | tophys(r1,r1); |
| 438 | RESTORE_REGS; |
| 439 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 440 | tovirt(r1,r1); |
| 441 | 6: |
| 442 | TRAP_return: /* Make global symbol for debugging */ |
| 443 | rtbd r14, 0; /* Instructions to return from an IRQ */ |
| 444 | nop; |
| 445 | |
| 446 | |
| 447 | /* These syscalls need access to the struct pt_regs on the stack, so we |
| 448 | implement them in assembly (they're basically all wrappers anyway). */ |
| 449 | |
| 450 | C_ENTRY(sys_fork_wrapper): |
| 451 | addi r5, r0, SIGCHLD /* Arg 0: flags */ |
| 452 | lwi r6, r1, PTO+PT_R1 /* Arg 1: child SP (use parent's) */ |
| 453 | la r7, r1, PTO /* Arg 2: parent context */ |
| 454 | add r8. r0, r0 /* Arg 3: (unused) */ |
| 455 | add r9, r0, r0; /* Arg 4: (unused) */ |
| 456 | add r10, r0, r0; /* Arg 5: (unused) */ |
| 457 | brid do_fork /* Do real work (tail-call) */ |
| 458 | nop; |
| 459 | |
| 460 | /* This the initial entry point for a new child thread, with an appropriate |
| 461 | stack in place that makes it look the the child is in the middle of an |
| 462 | syscall. This function is actually `returned to' from switch_thread |
| 463 | (copy_thread makes ret_from_fork the return address in each new thread's |
| 464 | saved context). */ |
| 465 | C_ENTRY(ret_from_fork): |
| 466 | bralid r15, schedule_tail; /* ...which is schedule_tail's arg */ |
| 467 | add r3, r5, r0; /* switch_thread returns the prev task */ |
| 468 | /* ( in the delay slot ) */ |
| 469 | add r3, r0, r0; /* Child's fork call should return 0. */ |
| 470 | brid ret_from_trap; /* Do normal trap return */ |
| 471 | nop; |
| 472 | |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 473 | C_ENTRY(sys_vfork): |
| 474 | brid microblaze_vfork /* Do real work (tail-call) */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 475 | la r5, r1, PTO |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 476 | |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 477 | C_ENTRY(sys_clone): |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 478 | bnei r6, 1f; /* See if child SP arg (arg 1) is 0. */ |
Michal Simek | 570e3e2 | 2010-06-04 13:06:27 +0200 | [diff] [blame] | 479 | lwi r6, r1, PTO + PT_R1; /* If so, use paret's stack ptr */ |
| 480 | 1: add r10, r0, r9; /* Arg 6: (child_tidptr) */ |
| 481 | add r9, r0, r8; /* Arg 5: (parent_tidptr) */ |
| 482 | add r8, r0, r7; /* Arg 4: (stack_size) */ |
| 483 | la r7, r1, PTO; /* Arg 3: pt_regs */ |
| 484 | brid do_fork /* Do real work (tail-call) */ |
| 485 | nop |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 486 | |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 487 | C_ENTRY(sys_execve): |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 488 | la r8, r1, PTO; /* add user context as 4th arg */ |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 489 | brid microblaze_execve; /* Do real work (tail-call).*/ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 490 | nop; |
| 491 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 492 | C_ENTRY(sys_rt_sigreturn_wrapper): |
| 493 | swi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ |
| 494 | swi r4, r1, PTO+PT_R4; |
| 495 | la r5, r1, PTO; /* add user context as 1st arg */ |
| 496 | brlid r15, sys_rt_sigreturn /* Do real work */ |
| 497 | nop; |
| 498 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ |
| 499 | lwi r4, r1, PTO+PT_R4; |
| 500 | bri ret_from_trap /* fall through will not work here due to align */ |
| 501 | nop; |
| 502 | |
| 503 | /* |
| 504 | * HW EXCEPTION rutine start |
| 505 | */ |
| 506 | |
| 507 | #define SAVE_STATE \ |
| 508 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ \ |
| 509 | set_bip; /*equalize initial state for all possible entries*/\ |
| 510 | clear_eip; \ |
| 511 | enable_irq; \ |
| 512 | set_ee; \ |
| 513 | /* See if already in kernel mode.*/ \ |
| 514 | lwi r11, r0, TOPHYS(PER_CPU(KM)); \ |
| 515 | beqi r11, 1f; /* Jump ahead if coming from user */\ |
| 516 | /* Kernel-mode state save. */ \ |
| 517 | /* Reload kernel stack-ptr. */ \ |
| 518 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ |
| 519 | tophys(r1,r11); \ |
| 520 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ \ |
| 521 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ |
| 522 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ |
| 523 | /* store return registers separately because \ |
| 524 | * this macros is use for others exceptions */ \ |
| 525 | swi r3, r1, PTO + PT_R3; \ |
| 526 | swi r4, r1, PTO + PT_R4; \ |
| 527 | SAVE_REGS \ |
| 528 | /* PC, before IRQ/trap - this is one instruction above */ \ |
| 529 | swi r17, r1, PTO+PT_PC; \ |
| 530 | \ |
| 531 | addi r11, r0, 1; /* Was in kernel-mode. */ \ |
| 532 | swi r11, r1, PTO+PT_MODE; \ |
| 533 | brid 2f; \ |
| 534 | nop; /* Fill delay slot */ \ |
| 535 | 1: /* User-mode state save. */ \ |
| 536 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ |
| 537 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\ |
| 538 | tophys(r1,r1); \ |
| 539 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ \ |
| 540 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */\ |
| 541 | tophys(r1,r1); \ |
| 542 | \ |
| 543 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ |
| 544 | /* store return registers separately because this macros \ |
| 545 | * is use for others exceptions */ \ |
| 546 | swi r3, r1, PTO + PT_R3; \ |
| 547 | swi r4, r1, PTO + PT_R4; \ |
| 548 | SAVE_REGS \ |
| 549 | /* PC, before IRQ/trap - this is one instruction above FIXME*/ \ |
| 550 | swi r17, r1, PTO+PT_PC; \ |
| 551 | \ |
| 552 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ \ |
| 553 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ |
| 554 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ \ |
| 555 | addi r11, r0, 1; \ |
| 556 | swi r11, r0, TOPHYS(PER_CPU(KM)); /* Now we're in kernel-mode.*/\ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 557 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); \ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 558 | /* Save away the syscall number. */ \ |
| 559 | swi r0, r1, PTO+PT_R0; \ |
| 560 | tovirt(r1,r1) |
| 561 | |
| 562 | C_ENTRY(full_exception_trap): |
| 563 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 564 | /* adjust exception address for privileged instruction |
| 565 | * for finding where is it */ |
| 566 | addik r17, r17, -4 |
| 567 | SAVE_STATE /* Save registers */ |
| 568 | /* FIXME this can be store directly in PT_ESR reg. |
| 569 | * I tested it but there is a fault */ |
| 570 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 571 | la r15, r0, ret_from_exc - 8 |
| 572 | la r5, r1, PTO /* parameter struct pt_regs * regs */ |
| 573 | mfs r6, resr |
| 574 | nop |
| 575 | mfs r7, rfsr; /* save FSR */ |
| 576 | nop |
Michal Simek | 131e4e9 | 2009-09-28 08:50:53 +0200 | [diff] [blame] | 577 | mts rfsr, r0; /* Clear sticky fsr */ |
| 578 | nop |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 579 | la r12, r0, full_exception |
| 580 | set_vms; |
| 581 | rtbd r12, 0; |
| 582 | nop; |
| 583 | |
| 584 | /* |
| 585 | * Unaligned data trap. |
| 586 | * |
| 587 | * Unaligned data trap last on 4k page is handled here. |
| 588 | * |
| 589 | * Trap entered via exception, so EE bit is set, and interrupts |
| 590 | * are masked. This is nice, means we don't have to CLI before state save |
| 591 | * |
| 592 | * The assembler routine is in "arch/microblaze/kernel/hw_exception_handler.S" |
| 593 | */ |
| 594 | C_ENTRY(unaligned_data_trap): |
| 595 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 596 | SAVE_STATE /* Save registers.*/ |
| 597 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 598 | la r15, r0, ret_from_exc-8 |
| 599 | mfs r3, resr /* ESR */ |
| 600 | nop |
| 601 | mfs r4, rear /* EAR */ |
| 602 | nop |
| 603 | la r7, r1, PTO /* parameter struct pt_regs * regs */ |
| 604 | la r12, r0, _unaligned_data_exception |
| 605 | set_vms; |
| 606 | rtbd r12, 0; /* interrupts enabled */ |
| 607 | nop; |
| 608 | |
| 609 | /* |
| 610 | * Page fault traps. |
| 611 | * |
| 612 | * If the real exception handler (from hw_exception_handler.S) didn't find |
| 613 | * the mapping for the process, then we're thrown here to handle such situation. |
| 614 | * |
| 615 | * Trap entered via exceptions, so EE bit is set, and interrupts |
| 616 | * are masked. This is nice, means we don't have to CLI before state save |
| 617 | * |
| 618 | * Build a standard exception frame for TLB Access errors. All TLB exceptions |
| 619 | * will bail out to this point if they can't resolve the lightweight TLB fault. |
| 620 | * |
| 621 | * The C function called is in "arch/microblaze/mm/fault.c", declared as: |
| 622 | * void do_page_fault(struct pt_regs *regs, |
| 623 | * unsigned long address, |
| 624 | * unsigned long error_code) |
| 625 | */ |
| 626 | /* data and intruction trap - which is choose is resolved int fault.c */ |
| 627 | C_ENTRY(page_fault_data_trap): |
| 628 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 629 | SAVE_STATE /* Save registers.*/ |
| 630 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 631 | la r15, r0, ret_from_exc-8 |
| 632 | la r5, r1, PTO /* parameter struct pt_regs * regs */ |
| 633 | mfs r6, rear /* parameter unsigned long address */ |
| 634 | nop |
| 635 | mfs r7, resr /* parameter unsigned long error_code */ |
| 636 | nop |
| 637 | la r12, r0, do_page_fault |
| 638 | set_vms; |
| 639 | rtbd r12, 0; /* interrupts enabled */ |
| 640 | nop; |
| 641 | |
| 642 | C_ENTRY(page_fault_instr_trap): |
| 643 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 644 | SAVE_STATE /* Save registers.*/ |
| 645 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 646 | la r15, r0, ret_from_exc-8 |
| 647 | la r5, r1, PTO /* parameter struct pt_regs * regs */ |
| 648 | mfs r6, rear /* parameter unsigned long address */ |
| 649 | nop |
| 650 | ori r7, r0, 0 /* parameter unsigned long error_code */ |
| 651 | la r12, r0, do_page_fault |
| 652 | set_vms; |
| 653 | rtbd r12, 0; /* interrupts enabled */ |
| 654 | nop; |
| 655 | |
| 656 | /* Entry point used to return from an exception. */ |
| 657 | C_ENTRY(ret_from_exc): |
| 658 | set_bip; /* Ints masked for state restore*/ |
| 659 | lwi r11, r1, PTO+PT_MODE; |
| 660 | bnei r11, 2f; /* See if returning to kernel mode, */ |
| 661 | /* ... if so, skip resched &c. */ |
| 662 | |
| 663 | /* We're returning to user mode, so check for various conditions that |
| 664 | trigger rescheduling. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 665 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 666 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 667 | andi r11, r11, _TIF_NEED_RESCHED; |
| 668 | beqi r11, 5f; |
| 669 | |
| 670 | /* Call the scheduler before returning from a syscall/trap. */ |
| 671 | bralid r15, schedule; /* Call scheduler */ |
| 672 | nop; /* delay slot */ |
| 673 | |
| 674 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 675 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 676 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 677 | andi r11, r11, _TIF_SIGPENDING; |
| 678 | beqi r11, 1f; /* Signals to handle, handle them */ |
| 679 | |
| 680 | /* |
| 681 | * Handle a signal return; Pending signals should be in r18. |
| 682 | * |
| 683 | * Not all registers are saved by the normal trap/interrupt entry |
| 684 | * points (for instance, call-saved registers (because the normal |
| 685 | * C-compiler calling sequence in the kernel makes sure they're |
| 686 | * preserved), and call-clobbered registers in the case of |
| 687 | * traps), but signal handlers may want to examine or change the |
| 688 | * complete register state. Here we save anything not saved by |
| 689 | * the normal entry sequence, so that it may be safely restored |
| 690 | * (in a possibly modified form) after do_signal returns. |
| 691 | * store return registers separately because this macros is use |
| 692 | * for others exceptions */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 693 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 694 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
| 695 | bralid r15, do_signal; /* Handle any signals */ |
Michal Simek | 841d6e8 | 2010-01-22 14:28:36 +0100 | [diff] [blame] | 696 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 697 | |
| 698 | /* Finally, return to user state. */ |
| 699 | 1: swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 700 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 701 | VM_OFF; |
| 702 | tophys(r1,r1); |
| 703 | |
| 704 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ |
| 705 | lwi r4, r1, PTO+PT_R4; |
| 706 | RESTORE_REGS; |
| 707 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 708 | |
| 709 | lwi r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer. */ |
| 710 | bri 6f; |
| 711 | /* Return to kernel state. */ |
| 712 | 2: VM_OFF; |
| 713 | tophys(r1,r1); |
| 714 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ |
| 715 | lwi r4, r1, PTO+PT_R4; |
| 716 | RESTORE_REGS; |
| 717 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 718 | |
| 719 | tovirt(r1,r1); |
| 720 | 6: |
| 721 | EXC_return: /* Make global symbol for debugging */ |
| 722 | rtbd r14, 0; /* Instructions to return from an IRQ */ |
| 723 | nop; |
| 724 | |
| 725 | /* |
| 726 | * HW EXCEPTION rutine end |
| 727 | */ |
| 728 | |
| 729 | /* |
| 730 | * Hardware maskable interrupts. |
| 731 | * |
| 732 | * The stack-pointer (r1) should have already been saved to the memory |
| 733 | * location PER_CPU(ENTRY_SP). |
| 734 | */ |
| 735 | C_ENTRY(_interrupt): |
| 736 | /* MS: we are in physical address */ |
| 737 | /* Save registers, switch to proper stack, convert SP to virtual.*/ |
| 738 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) |
| 739 | swi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); |
| 740 | /* MS: See if already in kernel mode. */ |
| 741 | lwi r11, r0, TOPHYS(PER_CPU(KM)); |
| 742 | beqi r11, 1f; /* MS: Jump ahead if coming from user */ |
| 743 | |
| 744 | /* Kernel-mode state save. */ |
| 745 | or r11, r1, r0 |
| 746 | tophys(r1,r11); /* MS: I have in r1 physical address where stack is */ |
| 747 | /* MS: Save original SP - position PT_R1 to next stack frame 4 *1 - 152*/ |
| 748 | swi r11, r1, (PT_R1 - PT_SIZE); |
| 749 | /* MS: restore r11 because of saving in SAVE_REGS */ |
| 750 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); |
| 751 | /* save registers */ |
| 752 | /* MS: Make room on the stack -> activation record */ |
| 753 | addik r1, r1, -STATE_SAVE_SIZE; |
| 754 | /* MS: store return registers separately because |
| 755 | * this macros is use for others exceptions */ |
| 756 | swi r3, r1, PTO + PT_R3; |
| 757 | swi r4, r1, PTO + PT_R4; |
| 758 | SAVE_REGS |
| 759 | /* MS: store mode */ |
| 760 | addi r11, r0, 1; /* MS: Was in kernel-mode. */ |
| 761 | swi r11, r1, PTO + PT_MODE; /* MS: and save it */ |
| 762 | brid 2f; |
| 763 | nop; /* MS: Fill delay slot */ |
| 764 | |
| 765 | 1: |
| 766 | /* User-mode state save. */ |
| 767 | /* MS: restore r11 -> FIXME move before SAVE_REG */ |
| 768 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); |
| 769 | /* MS: get the saved current */ |
| 770 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
| 771 | tophys(r1,r1); |
| 772 | lwi r1, r1, TS_THREAD_INFO; |
| 773 | addik r1, r1, THREAD_SIZE; |
| 774 | tophys(r1,r1); |
| 775 | /* save registers */ |
| 776 | addik r1, r1, -STATE_SAVE_SIZE; |
| 777 | swi r3, r1, PTO+PT_R3; |
| 778 | swi r4, r1, PTO+PT_R4; |
| 779 | SAVE_REGS |
| 780 | /* calculate mode */ |
| 781 | swi r0, r1, PTO + PT_MODE; |
| 782 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); |
| 783 | swi r11, r1, PTO+PT_R1; |
| 784 | /* setup kernel mode to KM */ |
| 785 | addi r11, r0, 1; |
| 786 | swi r11, r0, TOPHYS(PER_CPU(KM)); |
| 787 | |
| 788 | 2: |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 789 | lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 790 | swi r0, r1, PTO + PT_R0; |
| 791 | tovirt(r1,r1) |
| 792 | la r5, r1, PTO; |
| 793 | set_vms; |
| 794 | la r11, r0, do_IRQ; |
| 795 | la r15, r0, irq_call; |
| 796 | irq_call:rtbd r11, 0; |
| 797 | nop; |
| 798 | |
| 799 | /* MS: we are in virtual mode */ |
| 800 | ret_from_irq: |
| 801 | lwi r11, r1, PTO + PT_MODE; |
| 802 | bnei r11, 2f; |
| 803 | |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 804 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 805 | lwi r11, r11, TI_FLAGS; /* MS: get flags from thread info */ |
| 806 | andi r11, r11, _TIF_NEED_RESCHED; |
| 807 | beqi r11, 5f |
| 808 | bralid r15, schedule; |
| 809 | nop; /* delay slot */ |
| 810 | |
| 811 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 812 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* MS: get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 813 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 814 | andi r11, r11, _TIF_SIGPENDING; |
| 815 | beqid r11, no_intr_resched |
| 816 | /* Handle a signal return; Pending signals should be in r18. */ |
| 817 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
| 818 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
| 819 | bralid r15, do_signal; /* Handle any signals */ |
| 820 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
| 821 | |
| 822 | /* Finally, return to user state. */ |
| 823 | no_intr_resched: |
| 824 | /* Disable interrupts, we are now committed to the state restore */ |
| 825 | disable_irq |
| 826 | swi r0, r0, PER_CPU(KM); /* MS: Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 827 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 828 | VM_OFF; |
| 829 | tophys(r1,r1); |
| 830 | lwi r3, r1, PTO + PT_R3; /* MS: restore saved r3, r4 registers */ |
| 831 | lwi r4, r1, PTO + PT_R4; |
| 832 | RESTORE_REGS |
| 833 | addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */ |
| 834 | lwi r1, r1, PT_R1 - PT_SIZE; |
| 835 | bri 6f; |
| 836 | /* MS: Return to kernel state. */ |
Michal Simek | 7775379 | 2010-01-12 09:55:10 +0100 | [diff] [blame] | 837 | 2: |
| 838 | #ifdef CONFIG_PREEMPT |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 839 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | 7775379 | 2010-01-12 09:55:10 +0100 | [diff] [blame] | 840 | /* MS: get preempt_count from thread info */ |
| 841 | lwi r5, r11, TI_PREEMPT_COUNT; |
| 842 | bgti r5, restore; |
| 843 | |
| 844 | lwi r5, r11, TI_FLAGS; /* get flags in thread info */ |
| 845 | andi r5, r5, _TIF_NEED_RESCHED; |
| 846 | beqi r5, restore /* if zero jump over */ |
| 847 | |
| 848 | preempt: |
| 849 | /* interrupts are off that's why I am calling preempt_chedule_irq */ |
| 850 | bralid r15, preempt_schedule_irq |
| 851 | nop |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 852 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | 7775379 | 2010-01-12 09:55:10 +0100 | [diff] [blame] | 853 | lwi r5, r11, TI_FLAGS; /* get flags in thread info */ |
| 854 | andi r5, r5, _TIF_NEED_RESCHED; |
| 855 | bnei r5, preempt /* if non zero jump to resched */ |
| 856 | restore: |
| 857 | #endif |
| 858 | VM_OFF /* MS: turn off MMU */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 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 | tovirt(r1,r1); |
| 865 | 6: |
| 866 | IRQ_return: /* MS: Make global symbol for debugging */ |
| 867 | rtid r14, 0 |
| 868 | nop |
| 869 | |
| 870 | /* |
| 871 | * `Debug' trap |
| 872 | * We enter dbtrap in "BIP" (breakpoint) mode. |
| 873 | * So we exit the breakpoint mode with an 'rtbd' and proceed with the |
| 874 | * original dbtrap. |
| 875 | * however, wait to save state first |
| 876 | */ |
| 877 | C_ENTRY(_debug_exception): |
| 878 | /* BIP bit is set on entry, no interrupts can occur */ |
| 879 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) |
| 880 | |
| 881 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ |
| 882 | set_bip; /*equalize initial state for all possible entries*/ |
| 883 | clear_eip; |
| 884 | enable_irq; |
| 885 | lwi r11, r0, TOPHYS(PER_CPU(KM));/* See if already in kernel mode.*/ |
| 886 | beqi r11, 1f; /* Jump ahead if coming from user */ |
| 887 | /* Kernel-mode state save. */ |
| 888 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ |
| 889 | tophys(r1,r11); |
| 890 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ |
| 891 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 892 | |
| 893 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
| 894 | swi r3, r1, PTO + PT_R3; |
| 895 | swi r4, r1, PTO + PT_R4; |
| 896 | SAVE_REGS; |
| 897 | |
| 898 | addi r11, r0, 1; /* Was in kernel-mode. */ |
| 899 | swi r11, r1, PTO + PT_MODE; |
| 900 | brid 2f; |
| 901 | nop; /* Fill delay slot */ |
| 902 | 1: /* User-mode state save. */ |
| 903 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 904 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ |
| 905 | tophys(r1,r1); |
| 906 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ |
| 907 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */ |
| 908 | tophys(r1,r1); |
| 909 | |
| 910 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
| 911 | swi r3, r1, PTO + PT_R3; |
| 912 | swi r4, r1, PTO + PT_R4; |
| 913 | SAVE_REGS; |
| 914 | |
| 915 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ |
| 916 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); |
| 917 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ |
| 918 | addi r11, r0, 1; |
| 919 | swi r11, r0, TOPHYS(PER_CPU(KM)); /* Now we're in kernel-mode. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 920 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 921 | /* Save away the syscall number. */ |
| 922 | swi r0, r1, PTO+PT_R0; |
| 923 | tovirt(r1,r1) |
| 924 | |
| 925 | addi r5, r0, SIGTRAP /* send the trap signal */ |
| 926 | add r6, r0, CURRENT_TASK; /* Get current task ptr into r11 */ |
| 927 | addk r7, r0, r0 /* 3rd param zero */ |
| 928 | |
| 929 | set_vms; |
| 930 | la r11, r0, send_sig; |
| 931 | la r15, r0, dbtrap_call; |
| 932 | dbtrap_call: rtbd r11, 0; |
| 933 | nop; |
| 934 | |
| 935 | set_bip; /* Ints masked for state restore*/ |
| 936 | lwi r11, r1, PTO+PT_MODE; |
| 937 | bnei r11, 2f; |
| 938 | |
| 939 | /* Get current task ptr into r11 */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 940 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 941 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 942 | andi r11, r11, _TIF_NEED_RESCHED; |
| 943 | beqi r11, 5f; |
| 944 | |
| 945 | /* Call the scheduler before returning from a syscall/trap. */ |
| 946 | |
| 947 | bralid r15, schedule; /* Call scheduler */ |
| 948 | nop; /* delay slot */ |
| 949 | /* XXX Is PT_DTRACE handling needed here? */ |
| 950 | /* XXX m68knommu also checks TASK_STATE & TASK_COUNTER here. */ |
| 951 | |
| 952 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 953 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 954 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 955 | andi r11, r11, _TIF_SIGPENDING; |
| 956 | beqi r11, 1f; /* Signals to handle, handle them */ |
| 957 | |
| 958 | /* Handle a signal return; Pending signals should be in r18. */ |
| 959 | /* Not all registers are saved by the normal trap/interrupt entry |
| 960 | points (for instance, call-saved registers (because the normal |
| 961 | C-compiler calling sequence in the kernel makes sure they're |
| 962 | preserved), and call-clobbered registers in the case of |
| 963 | traps), but signal handlers may want to examine or change the |
| 964 | complete register state. Here we save anything not saved by |
| 965 | the normal entry sequence, so that it may be safely restored |
| 966 | (in a possibly modified form) after do_signal returns. */ |
| 967 | |
| 968 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 969 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
| 970 | bralid r15, do_signal; /* Handle any signals */ |
Michal Simek | 841d6e8 | 2010-01-22 14:28:36 +0100 | [diff] [blame] | 971 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 972 | |
| 973 | |
| 974 | /* Finally, return to user state. */ |
| 975 | 1: swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 976 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 977 | VM_OFF; |
| 978 | tophys(r1,r1); |
| 979 | |
| 980 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ |
| 981 | lwi r4, r1, PTO+PT_R4; |
| 982 | RESTORE_REGS |
| 983 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 984 | |
| 985 | |
| 986 | lwi r1, r1, PT_R1 - PT_SIZE; |
| 987 | /* Restore user stack pointer. */ |
| 988 | bri 6f; |
| 989 | |
| 990 | /* Return to kernel state. */ |
| 991 | 2: VM_OFF; |
| 992 | tophys(r1,r1); |
| 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 | tovirt(r1,r1); |
| 999 | 6: |
| 1000 | DBTRAP_return: /* Make global symbol for debugging */ |
| 1001 | rtbd r14, 0; /* Instructions to return from an IRQ */ |
| 1002 | nop; |
| 1003 | |
| 1004 | |
| 1005 | |
| 1006 | ENTRY(_switch_to) |
| 1007 | /* prepare return value */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 1008 | addk r3, r0, CURRENT_TASK |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 1009 | |
| 1010 | /* save registers in cpu_context */ |
| 1011 | /* use r11 and r12, volatile registers, as temp register */ |
| 1012 | /* give start of cpu_context for previous process */ |
| 1013 | addik r11, r5, TI_CPU_CONTEXT |
| 1014 | swi r1, r11, CC_R1 |
| 1015 | swi r2, r11, CC_R2 |
| 1016 | /* skip volatile registers. |
| 1017 | * they are saved on stack when we jumped to _switch_to() */ |
| 1018 | /* dedicated registers */ |
| 1019 | swi r13, r11, CC_R13 |
| 1020 | swi r14, r11, CC_R14 |
| 1021 | swi r15, r11, CC_R15 |
| 1022 | swi r16, r11, CC_R16 |
| 1023 | swi r17, r11, CC_R17 |
| 1024 | swi r18, r11, CC_R18 |
| 1025 | /* save non-volatile registers */ |
| 1026 | swi r19, r11, CC_R19 |
| 1027 | swi r20, r11, CC_R20 |
| 1028 | swi r21, r11, CC_R21 |
| 1029 | swi r22, r11, CC_R22 |
| 1030 | swi r23, r11, CC_R23 |
| 1031 | swi r24, r11, CC_R24 |
| 1032 | swi r25, r11, CC_R25 |
| 1033 | swi r26, r11, CC_R26 |
| 1034 | swi r27, r11, CC_R27 |
| 1035 | swi r28, r11, CC_R28 |
| 1036 | swi r29, r11, CC_R29 |
| 1037 | swi r30, r11, CC_R30 |
| 1038 | /* special purpose registers */ |
| 1039 | mfs r12, rmsr |
| 1040 | nop |
| 1041 | swi r12, r11, CC_MSR |
| 1042 | mfs r12, rear |
| 1043 | nop |
| 1044 | swi r12, r11, CC_EAR |
| 1045 | mfs r12, resr |
| 1046 | nop |
| 1047 | swi r12, r11, CC_ESR |
| 1048 | mfs r12, rfsr |
| 1049 | nop |
| 1050 | swi r12, r11, CC_FSR |
| 1051 | |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 1052 | /* update r31, the current-give me pointer to task which will be next */ |
| 1053 | lwi CURRENT_TASK, r6, TI_TASK |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 1054 | /* stored it to current_save too */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 1055 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE) |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 1056 | |
| 1057 | /* get new process' cpu context and restore */ |
| 1058 | /* give me start where start context of next task */ |
| 1059 | addik r11, r6, TI_CPU_CONTEXT |
| 1060 | |
| 1061 | /* non-volatile registers */ |
| 1062 | lwi r30, r11, CC_R30 |
| 1063 | lwi r29, r11, CC_R29 |
| 1064 | lwi r28, r11, CC_R28 |
| 1065 | lwi r27, r11, CC_R27 |
| 1066 | lwi r26, r11, CC_R26 |
| 1067 | lwi r25, r11, CC_R25 |
| 1068 | lwi r24, r11, CC_R24 |
| 1069 | lwi r23, r11, CC_R23 |
| 1070 | lwi r22, r11, CC_R22 |
| 1071 | lwi r21, r11, CC_R21 |
| 1072 | lwi r20, r11, CC_R20 |
| 1073 | lwi r19, r11, CC_R19 |
| 1074 | /* dedicated registers */ |
| 1075 | lwi r18, r11, CC_R18 |
| 1076 | lwi r17, r11, CC_R17 |
| 1077 | lwi r16, r11, CC_R16 |
| 1078 | lwi r15, r11, CC_R15 |
| 1079 | lwi r14, r11, CC_R14 |
| 1080 | lwi r13, r11, CC_R13 |
| 1081 | /* skip volatile registers */ |
| 1082 | lwi r2, r11, CC_R2 |
| 1083 | lwi r1, r11, CC_R1 |
| 1084 | |
| 1085 | /* special purpose registers */ |
| 1086 | lwi r12, r11, CC_FSR |
| 1087 | mts rfsr, r12 |
| 1088 | nop |
| 1089 | lwi r12, r11, CC_MSR |
| 1090 | mts rmsr, r12 |
| 1091 | nop |
| 1092 | |
| 1093 | rtsd r15, 8 |
| 1094 | nop |
| 1095 | |
| 1096 | ENTRY(_reset) |
| 1097 | brai 0x70; /* Jump back to FS-boot */ |
| 1098 | |
| 1099 | ENTRY(_break) |
| 1100 | mfs r5, rmsr |
| 1101 | nop |
| 1102 | swi r5, r0, 0x250 + TOPHYS(r0_ram) |
| 1103 | mfs r5, resr |
| 1104 | nop |
| 1105 | swi r5, r0, 0x254 + TOPHYS(r0_ram) |
| 1106 | bri 0 |
| 1107 | |
| 1108 | /* These are compiled and loaded into high memory, then |
| 1109 | * copied into place in mach_early_setup */ |
| 1110 | .section .init.ivt, "ax" |
| 1111 | .org 0x0 |
| 1112 | /* this is very important - here is the reset vector */ |
| 1113 | /* in current MMU branch you don't care what is here - it is |
| 1114 | * used from bootloader site - but this is correct for FS-BOOT */ |
| 1115 | brai 0x70 |
| 1116 | nop |
| 1117 | brai TOPHYS(_user_exception); /* syscall handler */ |
| 1118 | brai TOPHYS(_interrupt); /* Interrupt handler */ |
| 1119 | brai TOPHYS(_break); /* nmi trap handler */ |
| 1120 | brai TOPHYS(_hw_exception_handler); /* HW exception handler */ |
| 1121 | |
| 1122 | .org 0x60 |
| 1123 | brai TOPHYS(_debug_exception); /* debug trap handler*/ |
| 1124 | |
| 1125 | .section .rodata,"a" |
| 1126 | #include "syscall_table.S" |
| 1127 | |
| 1128 | syscall_table_size=(.-sys_call_table) |
| 1129 | |
Steven J. Magnani | ce3266c | 2010-04-27 12:37:54 -0500 | [diff] [blame^] | 1130 | type_SYSCALL: |
| 1131 | .ascii "SYSCALL\0" |
| 1132 | type_IRQ: |
| 1133 | .ascii "IRQ\0" |
| 1134 | type_IRQ_PREEMPT: |
| 1135 | .ascii "IRQ (PREEMPTED)\0" |
| 1136 | type_SYSCALL_PREEMPT: |
| 1137 | .ascii " SYSCALL (PREEMPTED)\0" |
| 1138 | |
| 1139 | /* |
| 1140 | * Trap decoding for stack unwinder |
| 1141 | * Tuples are (start addr, end addr, string) |
| 1142 | * If return address lies on [start addr, end addr], |
| 1143 | * unwinder displays 'string' |
| 1144 | */ |
| 1145 | |
| 1146 | .align 4 |
| 1147 | .global microblaze_trap_handlers |
| 1148 | microblaze_trap_handlers: |
| 1149 | /* Exact matches come first */ |
| 1150 | .word ret_from_trap; .word ret_from_trap ; .word type_SYSCALL |
| 1151 | .word ret_from_irq ; .word ret_from_irq ; .word type_IRQ |
| 1152 | /* Fuzzy matches go here */ |
| 1153 | .word ret_from_irq ; .word no_intr_resched ; .word type_IRQ_PREEMPT |
| 1154 | .word ret_from_trap; .word TRAP_return ; .word type_SYSCALL_PREEMPT |
| 1155 | /* End of table */ |
| 1156 | .word 0 ; .word 0 ; .word 0 |