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 \ |
Michal Simek | a4a94db | 2010-06-22 13:15:53 +0200 | [diff] [blame] | 183 | set_ums; \ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 184 | rted r0, 2f; \ |
Michal Simek | a4a94db | 2010-06-22 13:15:53 +0200 | [diff] [blame] | 185 | nop; \ |
| 186 | 2: |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 187 | |
| 188 | /* turn off virtual protected mode save and user mode save*/ |
| 189 | #define VM_OFF \ |
Michal Simek | a4a94db | 2010-06-22 13:15:53 +0200 | [diff] [blame] | 190 | clear_vms_ums; \ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 191 | rted r0, TOPHYS(1f); \ |
Michal Simek | a4a94db | 2010-06-22 13:15:53 +0200 | [diff] [blame] | 192 | nop; \ |
| 193 | 1: |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 194 | |
| 195 | #define SAVE_REGS \ |
| 196 | swi r2, r1, PTO+PT_R2; /* Save SDA */ \ |
Michal Simek | 36f6095 | 2010-06-22 13:27:43 +0200 | [diff] [blame^] | 197 | swi r3, r1, PTO+PT_R3; \ |
| 198 | swi r4, r1, PTO+PT_R4; \ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 199 | swi r5, r1, PTO+PT_R5; \ |
| 200 | swi r6, r1, PTO+PT_R6; \ |
| 201 | swi r7, r1, PTO+PT_R7; \ |
| 202 | swi r8, r1, PTO+PT_R8; \ |
| 203 | swi r9, r1, PTO+PT_R9; \ |
| 204 | swi r10, r1, PTO+PT_R10; \ |
| 205 | swi r11, r1, PTO+PT_R11; /* save clobbered regs after rval */\ |
| 206 | swi r12, r1, PTO+PT_R12; \ |
| 207 | swi r13, r1, PTO+PT_R13; /* Save SDA2 */ \ |
| 208 | swi r14, r1, PTO+PT_PC; /* PC, before IRQ/trap */ \ |
| 209 | swi r15, r1, PTO+PT_R15; /* Save LP */ \ |
| 210 | swi r18, r1, PTO+PT_R18; /* Save asm scratch reg */ \ |
| 211 | swi r19, r1, PTO+PT_R19; \ |
| 212 | swi r20, r1, PTO+PT_R20; \ |
| 213 | swi r21, r1, PTO+PT_R21; \ |
| 214 | swi r22, r1, PTO+PT_R22; \ |
| 215 | swi r23, r1, PTO+PT_R23; \ |
| 216 | swi r24, r1, PTO+PT_R24; \ |
| 217 | swi r25, r1, PTO+PT_R25; \ |
| 218 | swi r26, r1, PTO+PT_R26; \ |
| 219 | swi r27, r1, PTO+PT_R27; \ |
| 220 | swi r28, r1, PTO+PT_R28; \ |
| 221 | swi r29, r1, PTO+PT_R29; \ |
| 222 | swi r30, r1, PTO+PT_R30; \ |
| 223 | swi r31, r1, PTO+PT_R31; /* Save current task reg */ \ |
| 224 | mfs r11, rmsr; /* save MSR */ \ |
| 225 | nop; \ |
| 226 | swi r11, r1, PTO+PT_MSR; |
| 227 | |
| 228 | #define RESTORE_REGS \ |
| 229 | lwi r11, r1, PTO+PT_MSR; \ |
| 230 | mts rmsr , r11; \ |
| 231 | nop; \ |
| 232 | lwi r2, r1, PTO+PT_R2; /* restore SDA */ \ |
Michal Simek | 36f6095 | 2010-06-22 13:27:43 +0200 | [diff] [blame^] | 233 | lwi r3, r1, PTO+PT_R3; \ |
| 234 | lwi r4, r1, PTO+PT_R4; \ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 235 | lwi r5, r1, PTO+PT_R5; \ |
| 236 | lwi r6, r1, PTO+PT_R6; \ |
| 237 | lwi r7, r1, PTO+PT_R7; \ |
| 238 | lwi r8, r1, PTO+PT_R8; \ |
| 239 | lwi r9, r1, PTO+PT_R9; \ |
| 240 | lwi r10, r1, PTO+PT_R10; \ |
| 241 | lwi r11, r1, PTO+PT_R11; /* restore clobbered regs after rval */\ |
| 242 | lwi r12, r1, PTO+PT_R12; \ |
| 243 | lwi r13, r1, PTO+PT_R13; /* restore SDA2 */ \ |
| 244 | lwi r14, r1, PTO+PT_PC; /* RESTORE_LINK PC, before IRQ/trap */\ |
| 245 | lwi r15, r1, PTO+PT_R15; /* restore LP */ \ |
| 246 | lwi r18, r1, PTO+PT_R18; /* restore asm scratch reg */ \ |
| 247 | lwi r19, r1, PTO+PT_R19; \ |
| 248 | lwi r20, r1, PTO+PT_R20; \ |
| 249 | lwi r21, r1, PTO+PT_R21; \ |
| 250 | lwi r22, r1, PTO+PT_R22; \ |
| 251 | lwi r23, r1, PTO+PT_R23; \ |
| 252 | lwi r24, r1, PTO+PT_R24; \ |
| 253 | lwi r25, r1, PTO+PT_R25; \ |
| 254 | lwi r26, r1, PTO+PT_R26; \ |
| 255 | lwi r27, r1, PTO+PT_R27; \ |
| 256 | lwi r28, r1, PTO+PT_R28; \ |
| 257 | lwi r29, r1, PTO+PT_R29; \ |
| 258 | lwi r30, r1, PTO+PT_R30; \ |
| 259 | lwi r31, r1, PTO+PT_R31; /* Restore cur task reg */ |
| 260 | |
| 261 | .text |
| 262 | |
| 263 | /* |
| 264 | * User trap. |
| 265 | * |
| 266 | * System calls are handled here. |
| 267 | * |
| 268 | * Syscall protocol: |
| 269 | * Syscall number in r12, args in r5-r10 |
| 270 | * Return value in r3 |
| 271 | * |
| 272 | * Trap entered via brki instruction, so BIP bit is set, and interrupts |
| 273 | * are masked. This is nice, means we don't have to CLI before state save |
| 274 | */ |
| 275 | C_ENTRY(_user_exception): |
| 276 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 277 | addi r14, r14, 4 /* return address is 4 byte after call */ |
| 278 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ |
| 279 | |
| 280 | lwi r11, r0, TOPHYS(PER_CPU(KM));/* See if already in kernel mode.*/ |
| 281 | beqi r11, 1f; /* Jump ahead if coming from user */ |
| 282 | /* Kernel-mode state save. */ |
| 283 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ |
| 284 | tophys(r1,r11); |
| 285 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ |
| 286 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 287 | |
| 288 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
| 289 | SAVE_REGS |
| 290 | |
| 291 | addi r11, r0, 1; /* Was in kernel-mode. */ |
| 292 | swi r11, r1, PTO+PT_MODE; /* pt_regs -> kernel mode */ |
| 293 | brid 2f; |
| 294 | nop; /* Fill delay slot */ |
| 295 | |
| 296 | /* User-mode state save. */ |
| 297 | 1: |
| 298 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 299 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ |
| 300 | tophys(r1,r1); |
| 301 | lwi r1, r1, TS_THREAD_INFO; /* get stack from task_struct */ |
| 302 | /* calculate kernel stack pointer from task struct 8k */ |
| 303 | addik r1, r1, THREAD_SIZE; |
| 304 | tophys(r1,r1); |
| 305 | |
| 306 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
| 307 | SAVE_REGS |
| 308 | |
| 309 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ |
| 310 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); |
| 311 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ |
| 312 | addi r11, r0, 1; |
| 313 | 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] | 314 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 315 | /* Save away the syscall number. */ |
| 316 | swi r12, r1, PTO+PT_R0; |
| 317 | tovirt(r1,r1) |
| 318 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 319 | /* where the trap should return need -8 to adjust for rtsd r15, 8*/ |
| 320 | /* Jump to the appropriate function for the system call number in r12 |
| 321 | * (r12 is not preserved), or return an error if r12 is not valid. The LP |
| 322 | * register should point to the location where |
| 323 | * 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] | 324 | |
| 325 | # Step into virtual mode. |
| 326 | set_vms; |
| 327 | addik r11, r0, 3f |
| 328 | rtid r11, 0 |
| 329 | nop |
| 330 | 3: |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 331 | lwi r11, CURRENT_TASK, TS_THREAD_INFO /* get thread info */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 332 | lwi r11, r11, TI_FLAGS /* get flags in thread info */ |
| 333 | andi r11, r11, _TIF_WORK_SYSCALL_MASK |
| 334 | beqi r11, 4f |
| 335 | |
| 336 | addik r3, r0, -ENOSYS |
| 337 | swi r3, r1, PTO + PT_R3 |
| 338 | brlid r15, do_syscall_trace_enter |
| 339 | addik r5, r1, PTO + PT_R0 |
| 340 | |
| 341 | # do_syscall_trace_enter returns the new syscall nr. |
| 342 | addk r12, r0, r3 |
| 343 | lwi r5, r1, PTO+PT_R5; |
| 344 | lwi r6, r1, PTO+PT_R6; |
| 345 | lwi r7, r1, PTO+PT_R7; |
| 346 | lwi r8, r1, PTO+PT_R8; |
| 347 | lwi r9, r1, PTO+PT_R9; |
| 348 | lwi r10, r1, PTO+PT_R10; |
| 349 | 4: |
| 350 | /* Jump to the appropriate function for the system call number in r12 |
| 351 | * (r12 is not preserved), or return an error if r12 is not valid. |
| 352 | * The LP register should point to the location where the called function |
| 353 | * should return. [note that MAKE_SYS_CALL uses label 1] */ |
| 354 | /* See if the system call number is valid */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 355 | addi r11, r12, -__NR_syscalls; |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 356 | bgei r11,5f; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 357 | /* Figure out which function to use for this system call. */ |
| 358 | /* Note Microblaze barrel shift is optional, so don't rely on it */ |
| 359 | add r12, r12, r12; /* convert num -> ptr */ |
| 360 | add r12, r12, r12; |
| 361 | |
Michal Simek | 11d5136 | 2009-12-07 08:21:34 +0100 | [diff] [blame] | 362 | #ifdef DEBUG |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 363 | /* Trac syscalls and stored them to r0_ram */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 364 | lwi r3, r12, 0x400 + r0_ram |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 365 | addi r3, r3, 1 |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 366 | swi r3, r12, 0x400 + r0_ram |
Michal Simek | 11d5136 | 2009-12-07 08:21:34 +0100 | [diff] [blame] | 367 | #endif |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 368 | |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 369 | # 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 */ |
| 372 | la r15, r0, ret_from_trap-8 |
| 373 | bra r12 |
| 374 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 375 | /* The syscall number is invalid, return an error. */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 376 | 5: |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 377 | addi r3, r0, -ENOSYS; |
| 378 | rtsd r15,8; /* looks like a normal subroutine return */ |
| 379 | or r0, r0, r0 |
| 380 | |
| 381 | |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 382 | /* Entry point used to return from a syscall/trap */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 383 | /* We re-enable BIP bit before state restore */ |
| 384 | C_ENTRY(ret_from_trap): |
| 385 | set_bip; /* Ints masked for state restore*/ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 386 | swi r3, r1, PTO + PT_R3 |
| 387 | swi r4, r1, PTO + PT_R4 |
| 388 | |
Michal Simek | 36f6095 | 2010-06-22 13:27:43 +0200 | [diff] [blame^] | 389 | lwi r11, r1, PTO+PT_MODE; |
| 390 | /* See if returning to kernel mode, if so, skip resched &c. */ |
| 391 | bnei r11, 2f; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 392 | /* We're returning to user mode, so check for various conditions that |
| 393 | * trigger rescheduling. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 394 | /* FIXME: Restructure all these flag checks. */ |
| 395 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 396 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 397 | andi r11, r11, _TIF_WORK_SYSCALL_MASK |
| 398 | beqi r11, 1f |
| 399 | |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 400 | brlid r15, do_syscall_trace_leave |
| 401 | addik r5, r1, PTO + PT_R0 |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 402 | 1: |
Michal Simek | 2357548 | 2009-08-24 13:26:04 +0200 | [diff] [blame] | 403 | /* We're returning to user mode, so check for various conditions that |
| 404 | * trigger rescheduling. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 405 | /* get thread info from current task */ |
| 406 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 407 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 408 | andi r11, r11, _TIF_NEED_RESCHED; |
| 409 | beqi r11, 5f; |
| 410 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 411 | bralid r15, schedule; /* Call scheduler */ |
| 412 | nop; /* delay slot */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 413 | |
| 414 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 415 | 5: /* get thread info from current task*/ |
| 416 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 417 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 418 | andi r11, r11, _TIF_SIGPENDING; |
| 419 | beqi r11, 1f; /* Signals to handle, handle them */ |
| 420 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 421 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 422 | addi r7, r0, 1; /* Arg 3: int in_syscall */ |
| 423 | bralid r15, do_signal; /* Handle any signals */ |
Michal Simek | 841d6e8 | 2010-01-22 14:28:36 +0100 | [diff] [blame] | 424 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 425 | |
| 426 | /* Finally, return to user state. */ |
| 427 | 1: |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 428 | swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 429 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 430 | VM_OFF; |
| 431 | tophys(r1,r1); |
| 432 | RESTORE_REGS; |
| 433 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 434 | lwi r1, r1, PT_R1 - PT_SIZE;/* Restore user stack pointer. */ |
| 435 | bri 6f; |
| 436 | |
| 437 | /* Return to kernel state. */ |
| 438 | 2: VM_OFF; |
| 439 | tophys(r1,r1); |
| 440 | RESTORE_REGS; |
| 441 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 442 | tovirt(r1,r1); |
| 443 | 6: |
| 444 | TRAP_return: /* Make global symbol for debugging */ |
| 445 | rtbd r14, 0; /* Instructions to return from an IRQ */ |
| 446 | nop; |
| 447 | |
| 448 | |
| 449 | /* These syscalls need access to the struct pt_regs on the stack, so we |
| 450 | implement them in assembly (they're basically all wrappers anyway). */ |
| 451 | |
| 452 | C_ENTRY(sys_fork_wrapper): |
| 453 | addi r5, r0, SIGCHLD /* Arg 0: flags */ |
| 454 | lwi r6, r1, PTO+PT_R1 /* Arg 1: child SP (use parent's) */ |
| 455 | la r7, r1, PTO /* Arg 2: parent context */ |
| 456 | add r8. r0, r0 /* Arg 3: (unused) */ |
| 457 | add r9, r0, r0; /* Arg 4: (unused) */ |
| 458 | add r10, r0, r0; /* Arg 5: (unused) */ |
| 459 | brid do_fork /* Do real work (tail-call) */ |
| 460 | nop; |
| 461 | |
| 462 | /* This the initial entry point for a new child thread, with an appropriate |
| 463 | stack in place that makes it look the the child is in the middle of an |
| 464 | syscall. This function is actually `returned to' from switch_thread |
| 465 | (copy_thread makes ret_from_fork the return address in each new thread's |
| 466 | saved context). */ |
| 467 | C_ENTRY(ret_from_fork): |
| 468 | bralid r15, schedule_tail; /* ...which is schedule_tail's arg */ |
| 469 | add r3, r5, r0; /* switch_thread returns the prev task */ |
| 470 | /* ( in the delay slot ) */ |
| 471 | add r3, r0, r0; /* Child's fork call should return 0. */ |
| 472 | brid ret_from_trap; /* Do normal trap return */ |
| 473 | nop; |
| 474 | |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 475 | C_ENTRY(sys_vfork): |
| 476 | brid microblaze_vfork /* Do real work (tail-call) */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 477 | la r5, r1, PTO |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 478 | |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 479 | C_ENTRY(sys_clone): |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 480 | bnei r6, 1f; /* See if child SP arg (arg 1) is 0. */ |
Michal Simek | 570e3e2 | 2010-06-04 13:06:27 +0200 | [diff] [blame] | 481 | lwi r6, r1, PTO + PT_R1; /* If so, use paret's stack ptr */ |
| 482 | 1: add r10, r0, r9; /* Arg 6: (child_tidptr) */ |
| 483 | add r9, r0, r8; /* Arg 5: (parent_tidptr) */ |
| 484 | add r8, r0, r7; /* Arg 4: (stack_size) */ |
| 485 | la r7, r1, PTO; /* Arg 3: pt_regs */ |
| 486 | brid do_fork /* Do real work (tail-call) */ |
| 487 | nop |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 488 | |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 489 | C_ENTRY(sys_execve): |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 490 | la r8, r1, PTO; /* add user context as 4th arg */ |
Arnd Bergmann | e513588 | 2009-06-18 19:55:30 +0200 | [diff] [blame] | 491 | brid microblaze_execve; /* Do real work (tail-call).*/ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 492 | nop; |
| 493 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 494 | C_ENTRY(sys_rt_sigreturn_wrapper): |
| 495 | swi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ |
| 496 | swi r4, r1, PTO+PT_R4; |
| 497 | la r5, r1, PTO; /* add user context as 1st arg */ |
| 498 | brlid r15, sys_rt_sigreturn /* Do real work */ |
| 499 | nop; |
| 500 | lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */ |
| 501 | lwi r4, r1, PTO+PT_R4; |
| 502 | bri ret_from_trap /* fall through will not work here due to align */ |
| 503 | nop; |
| 504 | |
| 505 | /* |
| 506 | * HW EXCEPTION rutine start |
| 507 | */ |
| 508 | |
| 509 | #define SAVE_STATE \ |
| 510 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ \ |
| 511 | set_bip; /*equalize initial state for all possible entries*/\ |
| 512 | clear_eip; \ |
| 513 | enable_irq; \ |
| 514 | set_ee; \ |
| 515 | /* See if already in kernel mode.*/ \ |
| 516 | lwi r11, r0, TOPHYS(PER_CPU(KM)); \ |
| 517 | beqi r11, 1f; /* Jump ahead if coming from user */\ |
| 518 | /* Kernel-mode state save. */ \ |
| 519 | /* Reload kernel stack-ptr. */ \ |
| 520 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ |
| 521 | tophys(r1,r11); \ |
| 522 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ \ |
| 523 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ |
| 524 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 525 | SAVE_REGS \ |
| 526 | /* PC, before IRQ/trap - this is one instruction above */ \ |
| 527 | swi r17, r1, PTO+PT_PC; \ |
| 528 | \ |
| 529 | addi r11, r0, 1; /* Was in kernel-mode. */ \ |
| 530 | swi r11, r1, PTO+PT_MODE; \ |
| 531 | brid 2f; \ |
| 532 | nop; /* Fill delay slot */ \ |
| 533 | 1: /* User-mode state save. */ \ |
| 534 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\ |
| 535 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\ |
| 536 | tophys(r1,r1); \ |
| 537 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ \ |
| 538 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */\ |
| 539 | tophys(r1,r1); \ |
| 540 | \ |
| 541 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 542 | SAVE_REGS \ |
| 543 | /* PC, before IRQ/trap - this is one instruction above FIXME*/ \ |
| 544 | swi r17, r1, PTO+PT_PC; \ |
| 545 | \ |
| 546 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ \ |
| 547 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); \ |
| 548 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ \ |
| 549 | addi r11, r0, 1; \ |
| 550 | 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] | 551 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); \ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 552 | /* Save away the syscall number. */ \ |
| 553 | swi r0, r1, PTO+PT_R0; \ |
| 554 | tovirt(r1,r1) |
| 555 | |
| 556 | C_ENTRY(full_exception_trap): |
| 557 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 558 | /* adjust exception address for privileged instruction |
| 559 | * for finding where is it */ |
| 560 | addik r17, r17, -4 |
| 561 | SAVE_STATE /* Save registers */ |
| 562 | /* FIXME this can be store directly in PT_ESR reg. |
| 563 | * I tested it but there is a fault */ |
| 564 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 565 | la r15, r0, ret_from_exc - 8 |
| 566 | la r5, r1, PTO /* parameter struct pt_regs * regs */ |
| 567 | mfs r6, resr |
| 568 | nop |
| 569 | mfs r7, rfsr; /* save FSR */ |
| 570 | nop |
Michal Simek | 131e4e9 | 2009-09-28 08:50:53 +0200 | [diff] [blame] | 571 | mts rfsr, r0; /* Clear sticky fsr */ |
| 572 | nop |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 573 | la r12, r0, full_exception |
| 574 | set_vms; |
| 575 | rtbd r12, 0; |
| 576 | nop; |
| 577 | |
| 578 | /* |
| 579 | * Unaligned data trap. |
| 580 | * |
| 581 | * Unaligned data trap last on 4k page is handled here. |
| 582 | * |
| 583 | * Trap entered via exception, so EE bit is set, and interrupts |
| 584 | * are masked. This is nice, means we don't have to CLI before state save |
| 585 | * |
| 586 | * The assembler routine is in "arch/microblaze/kernel/hw_exception_handler.S" |
| 587 | */ |
| 588 | C_ENTRY(unaligned_data_trap): |
| 589 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 590 | SAVE_STATE /* Save registers.*/ |
| 591 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 592 | la r15, r0, ret_from_exc-8 |
| 593 | mfs r3, resr /* ESR */ |
| 594 | nop |
| 595 | mfs r4, rear /* EAR */ |
| 596 | nop |
| 597 | la r7, r1, PTO /* parameter struct pt_regs * regs */ |
| 598 | la r12, r0, _unaligned_data_exception |
| 599 | set_vms; |
| 600 | rtbd r12, 0; /* interrupts enabled */ |
| 601 | nop; |
| 602 | |
| 603 | /* |
| 604 | * Page fault traps. |
| 605 | * |
| 606 | * If the real exception handler (from hw_exception_handler.S) didn't find |
| 607 | * the mapping for the process, then we're thrown here to handle such situation. |
| 608 | * |
| 609 | * Trap entered via exceptions, so EE bit is set, and interrupts |
| 610 | * are masked. This is nice, means we don't have to CLI before state save |
| 611 | * |
| 612 | * Build a standard exception frame for TLB Access errors. All TLB exceptions |
| 613 | * will bail out to this point if they can't resolve the lightweight TLB fault. |
| 614 | * |
| 615 | * The C function called is in "arch/microblaze/mm/fault.c", declared as: |
| 616 | * void do_page_fault(struct pt_regs *regs, |
| 617 | * unsigned long address, |
| 618 | * unsigned long error_code) |
| 619 | */ |
| 620 | /* data and intruction trap - which is choose is resolved int fault.c */ |
| 621 | C_ENTRY(page_fault_data_trap): |
| 622 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 623 | SAVE_STATE /* Save registers.*/ |
| 624 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 625 | la r15, r0, ret_from_exc-8 |
| 626 | la r5, r1, PTO /* parameter struct pt_regs * regs */ |
| 627 | mfs r6, rear /* parameter unsigned long address */ |
| 628 | nop |
| 629 | mfs r7, resr /* parameter unsigned long error_code */ |
| 630 | nop |
| 631 | la r12, r0, do_page_fault |
| 632 | set_vms; |
| 633 | rtbd r12, 0; /* interrupts enabled */ |
| 634 | nop; |
| 635 | |
| 636 | C_ENTRY(page_fault_instr_trap): |
| 637 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */ |
| 638 | SAVE_STATE /* Save registers.*/ |
| 639 | /* where the trap should return need -8 to adjust for rtsd r15, 8 */ |
| 640 | la r15, r0, ret_from_exc-8 |
| 641 | la r5, r1, PTO /* parameter struct pt_regs * regs */ |
| 642 | mfs r6, rear /* parameter unsigned long address */ |
| 643 | nop |
| 644 | ori r7, r0, 0 /* parameter unsigned long error_code */ |
| 645 | la r12, r0, do_page_fault |
| 646 | set_vms; |
| 647 | rtbd r12, 0; /* interrupts enabled */ |
| 648 | nop; |
| 649 | |
| 650 | /* Entry point used to return from an exception. */ |
| 651 | C_ENTRY(ret_from_exc): |
| 652 | set_bip; /* Ints masked for state restore*/ |
| 653 | lwi r11, r1, PTO+PT_MODE; |
| 654 | bnei r11, 2f; /* See if returning to kernel mode, */ |
| 655 | /* ... if so, skip resched &c. */ |
| 656 | |
| 657 | /* We're returning to user mode, so check for various conditions that |
| 658 | trigger rescheduling. */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 659 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 660 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 661 | andi r11, r11, _TIF_NEED_RESCHED; |
| 662 | beqi r11, 5f; |
| 663 | |
| 664 | /* Call the scheduler before returning from a syscall/trap. */ |
| 665 | bralid r15, schedule; /* Call scheduler */ |
| 666 | nop; /* delay slot */ |
| 667 | |
| 668 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 669 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 670 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 671 | andi r11, r11, _TIF_SIGPENDING; |
| 672 | beqi r11, 1f; /* Signals to handle, handle them */ |
| 673 | |
| 674 | /* |
| 675 | * Handle a signal return; Pending signals should be in r18. |
| 676 | * |
| 677 | * Not all registers are saved by the normal trap/interrupt entry |
| 678 | * points (for instance, call-saved registers (because the normal |
| 679 | * C-compiler calling sequence in the kernel makes sure they're |
| 680 | * preserved), and call-clobbered registers in the case of |
| 681 | * traps), but signal handlers may want to examine or change the |
| 682 | * complete register state. Here we save anything not saved by |
| 683 | * the normal entry sequence, so that it may be safely restored |
Michal Simek | 36f6095 | 2010-06-22 13:27:43 +0200 | [diff] [blame^] | 684 | * (in a possibly modified form) after do_signal returns. */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 685 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 686 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
| 687 | bralid r15, do_signal; /* Handle any signals */ |
Michal Simek | 841d6e8 | 2010-01-22 14:28:36 +0100 | [diff] [blame] | 688 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 689 | |
| 690 | /* Finally, return to user state. */ |
| 691 | 1: swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 692 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 693 | VM_OFF; |
| 694 | tophys(r1,r1); |
| 695 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 696 | RESTORE_REGS; |
| 697 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 698 | |
| 699 | lwi r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer. */ |
| 700 | bri 6f; |
| 701 | /* Return to kernel state. */ |
| 702 | 2: VM_OFF; |
| 703 | tophys(r1,r1); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 704 | RESTORE_REGS; |
| 705 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 706 | |
| 707 | tovirt(r1,r1); |
| 708 | 6: |
| 709 | EXC_return: /* Make global symbol for debugging */ |
| 710 | rtbd r14, 0; /* Instructions to return from an IRQ */ |
| 711 | nop; |
| 712 | |
| 713 | /* |
| 714 | * HW EXCEPTION rutine end |
| 715 | */ |
| 716 | |
| 717 | /* |
| 718 | * Hardware maskable interrupts. |
| 719 | * |
| 720 | * The stack-pointer (r1) should have already been saved to the memory |
| 721 | * location PER_CPU(ENTRY_SP). |
| 722 | */ |
| 723 | C_ENTRY(_interrupt): |
| 724 | /* MS: we are in physical address */ |
| 725 | /* Save registers, switch to proper stack, convert SP to virtual.*/ |
| 726 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) |
| 727 | swi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); |
| 728 | /* MS: See if already in kernel mode. */ |
| 729 | lwi r11, r0, TOPHYS(PER_CPU(KM)); |
| 730 | beqi r11, 1f; /* MS: Jump ahead if coming from user */ |
| 731 | |
| 732 | /* Kernel-mode state save. */ |
| 733 | or r11, r1, r0 |
| 734 | tophys(r1,r11); /* MS: I have in r1 physical address where stack is */ |
| 735 | /* MS: Save original SP - position PT_R1 to next stack frame 4 *1 - 152*/ |
| 736 | swi r11, r1, (PT_R1 - PT_SIZE); |
| 737 | /* MS: restore r11 because of saving in SAVE_REGS */ |
| 738 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); |
| 739 | /* save registers */ |
| 740 | /* MS: Make room on the stack -> activation record */ |
| 741 | addik r1, r1, -STATE_SAVE_SIZE; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 742 | SAVE_REGS |
| 743 | /* MS: store mode */ |
| 744 | addi r11, r0, 1; /* MS: Was in kernel-mode. */ |
| 745 | swi r11, r1, PTO + PT_MODE; /* MS: and save it */ |
| 746 | brid 2f; |
| 747 | nop; /* MS: Fill delay slot */ |
| 748 | |
| 749 | 1: |
| 750 | /* User-mode state save. */ |
| 751 | /* MS: restore r11 -> FIXME move before SAVE_REG */ |
| 752 | lwi r11, r0, TOPHYS(PER_CPU(R11_SAVE)); |
| 753 | /* MS: get the saved current */ |
| 754 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
| 755 | tophys(r1,r1); |
| 756 | lwi r1, r1, TS_THREAD_INFO; |
| 757 | addik r1, r1, THREAD_SIZE; |
| 758 | tophys(r1,r1); |
| 759 | /* save registers */ |
| 760 | addik r1, r1, -STATE_SAVE_SIZE; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 761 | SAVE_REGS |
| 762 | /* calculate mode */ |
| 763 | swi r0, r1, PTO + PT_MODE; |
| 764 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); |
| 765 | swi r11, r1, PTO+PT_R1; |
| 766 | /* setup kernel mode to KM */ |
| 767 | addi r11, r0, 1; |
| 768 | swi r11, r0, TOPHYS(PER_CPU(KM)); |
| 769 | |
| 770 | 2: |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 771 | lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 772 | swi r0, r1, PTO + PT_R0; |
| 773 | tovirt(r1,r1) |
| 774 | la r5, r1, PTO; |
| 775 | set_vms; |
| 776 | la r11, r0, do_IRQ; |
| 777 | la r15, r0, irq_call; |
| 778 | irq_call:rtbd r11, 0; |
| 779 | nop; |
| 780 | |
| 781 | /* MS: we are in virtual mode */ |
| 782 | ret_from_irq: |
| 783 | lwi r11, r1, PTO + PT_MODE; |
| 784 | bnei r11, 2f; |
| 785 | |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 786 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 787 | lwi r11, r11, TI_FLAGS; /* MS: get flags from thread info */ |
| 788 | andi r11, r11, _TIF_NEED_RESCHED; |
| 789 | beqi r11, 5f |
| 790 | bralid r15, schedule; |
| 791 | nop; /* delay slot */ |
| 792 | |
| 793 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 794 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* MS: get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 795 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 796 | andi r11, r11, _TIF_SIGPENDING; |
| 797 | beqid r11, no_intr_resched |
| 798 | /* Handle a signal return; Pending signals should be in r18. */ |
| 799 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
| 800 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
| 801 | bralid r15, do_signal; /* Handle any signals */ |
| 802 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
| 803 | |
| 804 | /* Finally, return to user state. */ |
| 805 | no_intr_resched: |
| 806 | /* Disable interrupts, we are now committed to the state restore */ |
| 807 | disable_irq |
| 808 | swi r0, r0, PER_CPU(KM); /* MS: Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 809 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 810 | VM_OFF; |
| 811 | tophys(r1,r1); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 812 | RESTORE_REGS |
| 813 | addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */ |
| 814 | lwi r1, r1, PT_R1 - PT_SIZE; |
| 815 | bri 6f; |
| 816 | /* MS: Return to kernel state. */ |
Michal Simek | 7775379 | 2010-01-12 09:55:10 +0100 | [diff] [blame] | 817 | 2: |
| 818 | #ifdef CONFIG_PREEMPT |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 819 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; |
Michal Simek | 7775379 | 2010-01-12 09:55:10 +0100 | [diff] [blame] | 820 | /* MS: get preempt_count from thread info */ |
| 821 | lwi r5, r11, TI_PREEMPT_COUNT; |
| 822 | bgti r5, restore; |
| 823 | |
| 824 | lwi r5, r11, TI_FLAGS; /* get flags in thread info */ |
| 825 | andi r5, r5, _TIF_NEED_RESCHED; |
| 826 | beqi r5, restore /* if zero jump over */ |
| 827 | |
| 828 | preempt: |
| 829 | /* interrupts are off that's why I am calling preempt_chedule_irq */ |
| 830 | bralid r15, preempt_schedule_irq |
| 831 | nop |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 832 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | 7775379 | 2010-01-12 09:55:10 +0100 | [diff] [blame] | 833 | lwi r5, r11, TI_FLAGS; /* get flags in thread info */ |
| 834 | andi r5, r5, _TIF_NEED_RESCHED; |
| 835 | bnei r5, preempt /* if non zero jump to resched */ |
| 836 | restore: |
| 837 | #endif |
| 838 | VM_OFF /* MS: turn off MMU */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 839 | tophys(r1,r1) |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 840 | RESTORE_REGS |
| 841 | addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */ |
| 842 | tovirt(r1,r1); |
| 843 | 6: |
| 844 | IRQ_return: /* MS: Make global symbol for debugging */ |
| 845 | rtid r14, 0 |
| 846 | nop |
| 847 | |
| 848 | /* |
| 849 | * `Debug' trap |
| 850 | * We enter dbtrap in "BIP" (breakpoint) mode. |
| 851 | * So we exit the breakpoint mode with an 'rtbd' and proceed with the |
| 852 | * original dbtrap. |
| 853 | * however, wait to save state first |
| 854 | */ |
| 855 | C_ENTRY(_debug_exception): |
| 856 | /* BIP bit is set on entry, no interrupts can occur */ |
| 857 | swi r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) |
| 858 | |
| 859 | swi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */ |
| 860 | set_bip; /*equalize initial state for all possible entries*/ |
| 861 | clear_eip; |
| 862 | enable_irq; |
| 863 | lwi r11, r0, TOPHYS(PER_CPU(KM));/* See if already in kernel mode.*/ |
| 864 | beqi r11, 1f; /* Jump ahead if coming from user */ |
| 865 | /* Kernel-mode state save. */ |
| 866 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/ |
| 867 | tophys(r1,r11); |
| 868 | swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ |
| 869 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 870 | |
| 871 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 872 | SAVE_REGS; |
| 873 | |
| 874 | addi r11, r0, 1; /* Was in kernel-mode. */ |
| 875 | swi r11, r1, PTO + PT_MODE; |
| 876 | brid 2f; |
| 877 | nop; /* Fill delay slot */ |
| 878 | 1: /* User-mode state save. */ |
| 879 | lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */ |
| 880 | lwi r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */ |
| 881 | tophys(r1,r1); |
| 882 | lwi r1, r1, TS_THREAD_INFO; /* get the thread info */ |
| 883 | addik r1, r1, THREAD_SIZE; /* calculate kernel stack pointer */ |
| 884 | tophys(r1,r1); |
| 885 | |
| 886 | addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 887 | SAVE_REGS; |
| 888 | |
| 889 | swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */ |
| 890 | lwi r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); |
| 891 | swi r11, r1, PTO+PT_R1; /* Store user SP. */ |
| 892 | addi r11, r0, 1; |
| 893 | 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] | 894 | 2: lwi CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 895 | /* Save away the syscall number. */ |
| 896 | swi r0, r1, PTO+PT_R0; |
| 897 | tovirt(r1,r1) |
| 898 | |
| 899 | addi r5, r0, SIGTRAP /* send the trap signal */ |
| 900 | add r6, r0, CURRENT_TASK; /* Get current task ptr into r11 */ |
| 901 | addk r7, r0, r0 /* 3rd param zero */ |
| 902 | |
| 903 | set_vms; |
| 904 | la r11, r0, send_sig; |
| 905 | la r15, r0, dbtrap_call; |
| 906 | dbtrap_call: rtbd r11, 0; |
| 907 | nop; |
| 908 | |
| 909 | set_bip; /* Ints masked for state restore*/ |
| 910 | lwi r11, r1, PTO+PT_MODE; |
| 911 | bnei r11, 2f; |
| 912 | |
| 913 | /* Get current task ptr into r11 */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 914 | lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 915 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 916 | andi r11, r11, _TIF_NEED_RESCHED; |
| 917 | beqi r11, 5f; |
| 918 | |
| 919 | /* Call the scheduler before returning from a syscall/trap. */ |
| 920 | |
| 921 | bralid r15, schedule; /* Call scheduler */ |
| 922 | nop; /* delay slot */ |
| 923 | /* XXX Is PT_DTRACE handling needed here? */ |
| 924 | /* XXX m68knommu also checks TASK_STATE & TASK_COUNTER here. */ |
| 925 | |
| 926 | /* Maybe handle a signal */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 927 | 5: lwi r11, CURRENT_TASK, TS_THREAD_INFO; /* get thread info */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 928 | lwi r11, r11, TI_FLAGS; /* get flags in thread info */ |
| 929 | andi r11, r11, _TIF_SIGPENDING; |
| 930 | beqi r11, 1f; /* Signals to handle, handle them */ |
| 931 | |
| 932 | /* Handle a signal return; Pending signals should be in r18. */ |
| 933 | /* Not all registers are saved by the normal trap/interrupt entry |
| 934 | points (for instance, call-saved registers (because the normal |
| 935 | C-compiler calling sequence in the kernel makes sure they're |
| 936 | preserved), and call-clobbered registers in the case of |
| 937 | traps), but signal handlers may want to examine or change the |
| 938 | complete register state. Here we save anything not saved by |
| 939 | the normal entry sequence, so that it may be safely restored |
| 940 | (in a possibly modified form) after do_signal returns. */ |
| 941 | |
| 942 | la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 943 | addi r7, r0, 0; /* Arg 3: int in_syscall */ |
| 944 | bralid r15, do_signal; /* Handle any signals */ |
Michal Simek | 841d6e8 | 2010-01-22 14:28:36 +0100 | [diff] [blame] | 945 | add r6, r0, r0; /* Arg 2: sigset_t *oldset */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 946 | |
| 947 | |
| 948 | /* Finally, return to user state. */ |
| 949 | 1: swi r0, r0, PER_CPU(KM); /* Now officially in user state. */ |
Michal Simek | 8633beb | 2010-02-22 13:24:43 +0100 | [diff] [blame] | 950 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */ |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 951 | VM_OFF; |
| 952 | tophys(r1,r1); |
| 953 | |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 954 | RESTORE_REGS |
| 955 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 956 | |
| 957 | |
| 958 | lwi r1, r1, PT_R1 - PT_SIZE; |
| 959 | /* Restore user stack pointer. */ |
| 960 | bri 6f; |
| 961 | |
| 962 | /* Return to kernel state. */ |
| 963 | 2: VM_OFF; |
| 964 | tophys(r1,r1); |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 965 | RESTORE_REGS |
| 966 | addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */ |
| 967 | |
| 968 | tovirt(r1,r1); |
| 969 | 6: |
| 970 | DBTRAP_return: /* Make global symbol for debugging */ |
| 971 | rtbd r14, 0; /* Instructions to return from an IRQ */ |
| 972 | nop; |
| 973 | |
| 974 | |
| 975 | |
| 976 | ENTRY(_switch_to) |
| 977 | /* prepare return value */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 978 | addk r3, r0, CURRENT_TASK |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 979 | |
| 980 | /* save registers in cpu_context */ |
| 981 | /* use r11 and r12, volatile registers, as temp register */ |
| 982 | /* give start of cpu_context for previous process */ |
| 983 | addik r11, r5, TI_CPU_CONTEXT |
| 984 | swi r1, r11, CC_R1 |
| 985 | swi r2, r11, CC_R2 |
| 986 | /* skip volatile registers. |
| 987 | * they are saved on stack when we jumped to _switch_to() */ |
| 988 | /* dedicated registers */ |
| 989 | swi r13, r11, CC_R13 |
| 990 | swi r14, r11, CC_R14 |
| 991 | swi r15, r11, CC_R15 |
| 992 | swi r16, r11, CC_R16 |
| 993 | swi r17, r11, CC_R17 |
| 994 | swi r18, r11, CC_R18 |
| 995 | /* save non-volatile registers */ |
| 996 | swi r19, r11, CC_R19 |
| 997 | swi r20, r11, CC_R20 |
| 998 | swi r21, r11, CC_R21 |
| 999 | swi r22, r11, CC_R22 |
| 1000 | swi r23, r11, CC_R23 |
| 1001 | swi r24, r11, CC_R24 |
| 1002 | swi r25, r11, CC_R25 |
| 1003 | swi r26, r11, CC_R26 |
| 1004 | swi r27, r11, CC_R27 |
| 1005 | swi r28, r11, CC_R28 |
| 1006 | swi r29, r11, CC_R29 |
| 1007 | swi r30, r11, CC_R30 |
| 1008 | /* special purpose registers */ |
| 1009 | mfs r12, rmsr |
| 1010 | nop |
| 1011 | swi r12, r11, CC_MSR |
| 1012 | mfs r12, rear |
| 1013 | nop |
| 1014 | swi r12, r11, CC_EAR |
| 1015 | mfs r12, resr |
| 1016 | nop |
| 1017 | swi r12, r11, CC_ESR |
| 1018 | mfs r12, rfsr |
| 1019 | nop |
| 1020 | swi r12, r11, CC_FSR |
| 1021 | |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 1022 | /* update r31, the current-give me pointer to task which will be next */ |
| 1023 | lwi CURRENT_TASK, r6, TI_TASK |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 1024 | /* stored it to current_save too */ |
Michal Simek | b1d70c6 | 2010-01-22 10:24:06 +0100 | [diff] [blame] | 1025 | swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE) |
Michal Simek | ca54502 | 2009-05-26 16:30:21 +0200 | [diff] [blame] | 1026 | |
| 1027 | /* get new process' cpu context and restore */ |
| 1028 | /* give me start where start context of next task */ |
| 1029 | addik r11, r6, TI_CPU_CONTEXT |
| 1030 | |
| 1031 | /* non-volatile registers */ |
| 1032 | lwi r30, r11, CC_R30 |
| 1033 | lwi r29, r11, CC_R29 |
| 1034 | lwi r28, r11, CC_R28 |
| 1035 | lwi r27, r11, CC_R27 |
| 1036 | lwi r26, r11, CC_R26 |
| 1037 | lwi r25, r11, CC_R25 |
| 1038 | lwi r24, r11, CC_R24 |
| 1039 | lwi r23, r11, CC_R23 |
| 1040 | lwi r22, r11, CC_R22 |
| 1041 | lwi r21, r11, CC_R21 |
| 1042 | lwi r20, r11, CC_R20 |
| 1043 | lwi r19, r11, CC_R19 |
| 1044 | /* dedicated registers */ |
| 1045 | lwi r18, r11, CC_R18 |
| 1046 | lwi r17, r11, CC_R17 |
| 1047 | lwi r16, r11, CC_R16 |
| 1048 | lwi r15, r11, CC_R15 |
| 1049 | lwi r14, r11, CC_R14 |
| 1050 | lwi r13, r11, CC_R13 |
| 1051 | /* skip volatile registers */ |
| 1052 | lwi r2, r11, CC_R2 |
| 1053 | lwi r1, r11, CC_R1 |
| 1054 | |
| 1055 | /* special purpose registers */ |
| 1056 | lwi r12, r11, CC_FSR |
| 1057 | mts rfsr, r12 |
| 1058 | nop |
| 1059 | lwi r12, r11, CC_MSR |
| 1060 | mts rmsr, r12 |
| 1061 | nop |
| 1062 | |
| 1063 | rtsd r15, 8 |
| 1064 | nop |
| 1065 | |
| 1066 | ENTRY(_reset) |
| 1067 | brai 0x70; /* Jump back to FS-boot */ |
| 1068 | |
| 1069 | ENTRY(_break) |
| 1070 | mfs r5, rmsr |
| 1071 | nop |
| 1072 | swi r5, r0, 0x250 + TOPHYS(r0_ram) |
| 1073 | mfs r5, resr |
| 1074 | nop |
| 1075 | swi r5, r0, 0x254 + TOPHYS(r0_ram) |
| 1076 | bri 0 |
| 1077 | |
| 1078 | /* These are compiled and loaded into high memory, then |
| 1079 | * copied into place in mach_early_setup */ |
| 1080 | .section .init.ivt, "ax" |
| 1081 | .org 0x0 |
| 1082 | /* this is very important - here is the reset vector */ |
| 1083 | /* in current MMU branch you don't care what is here - it is |
| 1084 | * used from bootloader site - but this is correct for FS-BOOT */ |
| 1085 | brai 0x70 |
| 1086 | nop |
| 1087 | brai TOPHYS(_user_exception); /* syscall handler */ |
| 1088 | brai TOPHYS(_interrupt); /* Interrupt handler */ |
| 1089 | brai TOPHYS(_break); /* nmi trap handler */ |
| 1090 | brai TOPHYS(_hw_exception_handler); /* HW exception handler */ |
| 1091 | |
| 1092 | .org 0x60 |
| 1093 | brai TOPHYS(_debug_exception); /* debug trap handler*/ |
| 1094 | |
| 1095 | .section .rodata,"a" |
| 1096 | #include "syscall_table.S" |
| 1097 | |
| 1098 | syscall_table_size=(.-sys_call_table) |
| 1099 | |
Steven J. Magnani | ce3266c | 2010-04-27 12:37:54 -0500 | [diff] [blame] | 1100 | type_SYSCALL: |
| 1101 | .ascii "SYSCALL\0" |
| 1102 | type_IRQ: |
| 1103 | .ascii "IRQ\0" |
| 1104 | type_IRQ_PREEMPT: |
| 1105 | .ascii "IRQ (PREEMPTED)\0" |
| 1106 | type_SYSCALL_PREEMPT: |
| 1107 | .ascii " SYSCALL (PREEMPTED)\0" |
| 1108 | |
| 1109 | /* |
| 1110 | * Trap decoding for stack unwinder |
| 1111 | * Tuples are (start addr, end addr, string) |
| 1112 | * If return address lies on [start addr, end addr], |
| 1113 | * unwinder displays 'string' |
| 1114 | */ |
| 1115 | |
| 1116 | .align 4 |
| 1117 | .global microblaze_trap_handlers |
| 1118 | microblaze_trap_handlers: |
| 1119 | /* Exact matches come first */ |
| 1120 | .word ret_from_trap; .word ret_from_trap ; .word type_SYSCALL |
| 1121 | .word ret_from_irq ; .word ret_from_irq ; .word type_IRQ |
| 1122 | /* Fuzzy matches go here */ |
| 1123 | .word ret_from_irq ; .word no_intr_resched ; .word type_IRQ_PREEMPT |
| 1124 | .word ret_from_trap; .word TRAP_return ; .word type_SYSCALL_PREEMPT |
| 1125 | /* End of table */ |
| 1126 | .word 0 ; .word 0 ; .word 0 |