1/* 2 * Copyright 2011 Tilera Corporation. All Rights Reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation, version 2. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 11 * NON INFRINGEMENT. See the GNU General Public License for 12 * more details. 13 * 14 * Linux interrupt vectors. 15 */ 16 17#include <linux/linkage.h> 18#include <linux/errno.h> 19#include <linux/unistd.h> 20#include <linux/init.h> 21#include <asm/ptrace.h> 22#include <asm/thread_info.h> 23#include <asm/irqflags.h> 24#include <asm/asm-offsets.h> 25#include <asm/types.h> 26#include <asm/traps.h> 27#include <asm/signal.h> 28#include <hv/hypervisor.h> 29#include <arch/abi.h> 30#include <arch/interrupts.h> 31#include <arch/spr_def.h> 32 33#define PTREGS_PTR(reg, ptreg) addli reg, sp, C_ABI_SAVE_AREA_SIZE + (ptreg) 34 35#define PTREGS_OFFSET_SYSCALL PTREGS_OFFSET_REG(TREG_SYSCALL_NR) 36 37#if CONFIG_KERNEL_PL == 1 || CONFIG_KERNEL_PL == 2 38/* 39 * Set "result" non-zero if ex1 holds the PL of the kernel 40 * (with or without ICS being set). Note this works only 41 * because we never find the PL at level 3. 42 */ 43# define IS_KERNEL_EX1(result, ex1) andi result, ex1, CONFIG_KERNEL_PL 44#else 45# error Recode IS_KERNEL_EX1 for CONFIG_KERNEL_PL 46#endif 47 48 .macro push_reg reg, ptr=sp, delta=-8 49 { 50 st \ptr, \reg 51 addli \ptr, \ptr, \delta 52 } 53 .endm 54 55 .macro pop_reg reg, ptr=sp, delta=8 56 { 57 ld \reg, \ptr 58 addli \ptr, \ptr, \delta 59 } 60 .endm 61 62 .macro pop_reg_zero reg, zreg, ptr=sp, delta=8 63 { 64 move \zreg, zero 65 ld \reg, \ptr 66 addi \ptr, \ptr, \delta 67 } 68 .endm 69 70 .macro push_extra_callee_saves reg 71 PTREGS_PTR(\reg, PTREGS_OFFSET_REG(51)) 72 push_reg r51, \reg 73 push_reg r50, \reg 74 push_reg r49, \reg 75 push_reg r48, \reg 76 push_reg r47, \reg 77 push_reg r46, \reg 78 push_reg r45, \reg 79 push_reg r44, \reg 80 push_reg r43, \reg 81 push_reg r42, \reg 82 push_reg r41, \reg 83 push_reg r40, \reg 84 push_reg r39, \reg 85 push_reg r38, \reg 86 push_reg r37, \reg 87 push_reg r36, \reg 88 push_reg r35, \reg 89 push_reg r34, \reg, PTREGS_OFFSET_BASE - PTREGS_OFFSET_REG(34) 90 .endm 91 92 .macro panic str 93 .pushsection .rodata, "a" 941: 95 .asciz "\str" 96 .popsection 97 { 98 moveli r0, hw2_last(1b) 99 } 100 { 101 shl16insli r0, r0, hw1(1b) 102 } 103 { 104 shl16insli r0, r0, hw0(1b) 105 jal panic 106 } 107 .endm 108 109 /* 110 * Unalign data exception fast handling: In order to handle 111 * unaligned data access, a fast JIT version is generated and stored 112 * in a specific area in user space. We first need to do a quick poke 113 * to see if the JIT is available. We use certain bits in the fault 114 * PC (3 to 9 is used for 16KB page size) as index to address the JIT 115 * code area. The first 64bit word is the fault PC, and the 2nd one is 116 * the fault bundle itself. If these 2 words both match, then we 117 * directly "iret" to JIT code. If not, a slow path is invoked to 118 * generate new JIT code. Note: the current JIT code WILL be 119 * overwritten if it existed. So, ideally we can handle 128 unalign 120 * fixups via JIT. For lookup efficiency and to effectively support 121 * tight loops with multiple unaligned reference, a simple 122 * direct-mapped cache is used. 123 * 124 * SPR_EX_CONTEXT_K_0 is modified to return to JIT code. 125 * SPR_EX_CONTEXT_K_1 has ICS set. 126 * SPR_EX_CONTEXT_0_0 is setup to user program's next PC. 127 * SPR_EX_CONTEXT_0_1 = 0. 128 */ 129 .macro int_hand_unalign_fast vecnum, vecname 130 .org (\vecnum << 8) 131intvec_\vecname: 132 /* Put r3 in SPR_SYSTEM_SAVE_K_1. */ 133 mtspr SPR_SYSTEM_SAVE_K_1, r3 134 135 mfspr r3, SPR_EX_CONTEXT_K_1 136 /* 137 * Examine if exception comes from user without ICS set. 138 * If not, just go directly to the slow path. 139 */ 140 bnez r3, hand_unalign_slow_nonuser 141 142 mfspr r3, SPR_SYSTEM_SAVE_K_0 143 144 /* Get &thread_info->unalign_jit_tmp[0] in r3. */ 145 bfexts r3, r3, 0, CPU_SHIFT-1 146 mm r3, zero, LOG2_THREAD_SIZE, 63 147 addli r3, r3, THREAD_INFO_UNALIGN_JIT_TMP_OFFSET 148 149 /* 150 * Save r0, r1, r2 into thread_info array r3 points to 151 * from low to high memory in order. 152 */ 153 st_add r3, r0, 8 154 st_add r3, r1, 8 155 { 156 st_add r3, r2, 8 157 andi r2, sp, 7 158 } 159 160 /* Save stored r3 value so we can revert it on a page fault. */ 161 mfspr r1, SPR_SYSTEM_SAVE_K_1 162 st r3, r1 163 164 { 165 /* Generate a SIGBUS if sp is not 8-byte aligned. */ 166 bnez r2, hand_unalign_slow_badsp 167 } 168 169 /* 170 * Get the thread_info in r0; load r1 with pc. Set the low bit of sp 171 * as an indicator to the page fault code in case we fault. 172 */ 173 { 174 ori sp, sp, 1 175 mfspr r1, SPR_EX_CONTEXT_K_0 176 } 177 178 /* Add the jit_info offset in thread_info; extract r1 [3:9] into r2. */ 179 { 180 addli r0, r3, THREAD_INFO_UNALIGN_JIT_BASE_OFFSET - \ 181 (THREAD_INFO_UNALIGN_JIT_TMP_OFFSET + (3 * 8)) 182 bfextu r2, r1, 3, (2 + PAGE_SHIFT - UNALIGN_JIT_SHIFT) 183 } 184 185 /* Load the jit_info; multiply r2 by 128. */ 186 { 187 ld r0, r0 188 shli r2, r2, UNALIGN_JIT_SHIFT 189 } 190 191 /* 192 * If r0 is NULL, the JIT page is not mapped, so go to slow path; 193 * add offset r2 to r0 at the same time. 194 */ 195 { 196 beqz r0, hand_unalign_slow 197 add r2, r0, r2 198 } 199 200 /* 201 * We are loading from userspace (both the JIT info PC and 202 * instruction word, and the instruction word we executed) 203 * and since either could fault while holding the interrupt 204 * critical section, we must tag this region and check it in 205 * do_page_fault() to handle it properly. 206 */ 207ENTRY(__start_unalign_asm_code) 208 209 /* Load first word of JIT in r0 and increment r2 by 8. */ 210 ld_add r0, r2, 8 211 212 /* 213 * Compare the PC with the 1st word in JIT; load the fault bundle 214 * into r1. 215 */ 216 { 217 cmpeq r0, r0, r1 218 ld r1, r1 219 } 220 221 /* Go to slow path if PC doesn't match. */ 222 beqz r0, hand_unalign_slow 223 224 /* 225 * Load the 2nd word of JIT, which is supposed to be the fault 226 * bundle for a cache hit. Increment r2; after this bundle r2 will 227 * point to the potential start of the JIT code we want to run. 228 */ 229 ld_add r0, r2, 8 230 231 /* No further accesses to userspace are done after this point. */ 232ENTRY(__end_unalign_asm_code) 233 234 /* Compare the real bundle with what is saved in the JIT area. */ 235 { 236 cmpeq r0, r1, r0 237 mtspr SPR_EX_CONTEXT_0_1, zero 238 } 239 240 /* Go to slow path if the fault bundle does not match. */ 241 beqz r0, hand_unalign_slow 242 243 /* 244 * A cache hit is found. 245 * r2 points to start of JIT code (3rd word). 246 * r0 is the fault pc. 247 * r1 is the fault bundle. 248 * Reset the low bit of sp. 249 */ 250 { 251 mfspr r0, SPR_EX_CONTEXT_K_0 252 andi sp, sp, ~1 253 } 254 255 /* Write r2 into EX_CONTEXT_K_0 and increment PC. */ 256 { 257 mtspr SPR_EX_CONTEXT_K_0, r2 258 addi r0, r0, 8 259 } 260 261 /* 262 * Set ICS on kernel EX_CONTEXT_K_1 in order to "iret" to 263 * user with ICS set. This way, if the JIT fixup causes another 264 * unalign exception (which shouldn't be possible) the user 265 * process will be terminated with SIGBUS. Also, our fixup will 266 * run without interleaving with external interrupts. 267 * Each fixup is at most 14 bundles, so it won't hold ICS for long. 268 */ 269 { 270 movei r1, PL_ICS_EX1(USER_PL, 1) 271 mtspr SPR_EX_CONTEXT_0_0, r0 272 } 273 274 { 275 mtspr SPR_EX_CONTEXT_K_1, r1 276 addi r3, r3, -(3 * 8) 277 } 278 279 /* Restore r0..r3. */ 280 ld_add r0, r3, 8 281 ld_add r1, r3, 8 282 ld_add r2, r3, 8 283 ld r3, r3 284 285 iret 286 ENDPROC(intvec_\vecname) 287 .endm 288 289#ifdef __COLLECT_LINKER_FEEDBACK__ 290 .pushsection .text.intvec_feedback,"ax" 291intvec_feedback: 292 .popsection 293#endif 294 295 /* 296 * Default interrupt handler. 297 * 298 * vecnum is where we'll put this code. 299 * c_routine is the C routine we'll call. 300 * 301 * The C routine is passed two arguments: 302 * - A pointer to the pt_regs state. 303 * - The interrupt vector number. 304 * 305 * The "processing" argument specifies the code for processing 306 * the interrupt. Defaults to "handle_interrupt". 307 */ 308 .macro __int_hand vecnum, vecname, c_routine,processing=handle_interrupt 309intvec_\vecname: 310 /* Temporarily save a register so we have somewhere to work. */ 311 312 mtspr SPR_SYSTEM_SAVE_K_1, r0 313 mfspr r0, SPR_EX_CONTEXT_K_1 314 315 /* 316 * The unalign data fastpath code sets the low bit in sp to 317 * force us to reset it here on fault. 318 */ 319 { 320 blbs sp, 2f 321 IS_KERNEL_EX1(r0, r0) 322 } 323 324 .ifc \vecnum, INT_DOUBLE_FAULT 325 /* 326 * For double-faults from user-space, fall through to the normal 327 * register save and stack setup path. Otherwise, it's the 328 * hypervisor giving us one last chance to dump diagnostics, and we 329 * branch to the kernel_double_fault routine to do so. 330 */ 331 beqz r0, 1f 332 j _kernel_double_fault 3331: 334 .else 335 /* 336 * If we're coming from user-space, then set sp to the top of 337 * the kernel stack. Otherwise, assume sp is already valid. 338 */ 339 { 340 bnez r0, 0f 341 move r0, sp 342 } 343 .endif 344 345 .ifc \c_routine, do_page_fault 346 /* 347 * The page_fault handler may be downcalled directly by the 348 * hypervisor even when Linux is running and has ICS set. 349 * 350 * In this case the contents of EX_CONTEXT_K_1 reflect the 351 * previous fault and can't be relied on to choose whether or 352 * not to reinitialize the stack pointer. So we add a test 353 * to see whether SYSTEM_SAVE_K_2 has the high bit set, 354 * and if so we don't reinitialize sp, since we must be coming 355 * from Linux. (In fact the precise case is !(val & ~1), 356 * but any Linux PC has to have the high bit set.) 357 * 358 * Note that the hypervisor *always* sets SYSTEM_SAVE_K_2 for 359 * any path that turns into a downcall to one of our TLB handlers. 360 * 361 * FIXME: if we end up never using this path, perhaps we should 362 * prevent the hypervisor from generating downcalls in this case. 363 * The advantage of getting a downcall is we can panic in Linux. 364 */ 365 mfspr r0, SPR_SYSTEM_SAVE_K_2 366 { 367 bltz r0, 0f /* high bit in S_S_1_2 is for a PC to use */ 368 move r0, sp 369 } 370 .endif 371 3722: 373 /* 374 * SYSTEM_SAVE_K_0 holds the cpu number in the high bits, and 375 * the current stack top in the lower bits. So we recover 376 * our starting stack value by sign-extending the low bits, then 377 * point sp at the top aligned address on the actual stack page. 378 */ 379 mfspr r0, SPR_SYSTEM_SAVE_K_0 380 bfexts r0, r0, 0, CPU_SHIFT-1 381 3820: 383 /* 384 * Align the stack mod 64 so we can properly predict what 385 * cache lines we need to write-hint to reduce memory fetch 386 * latency as we enter the kernel. The layout of memory is 387 * as follows, with cache line 0 at the lowest VA, and cache 388 * line 8 just below the r0 value this "andi" computes. 389 * Note that we never write to cache line 8, and we skip 390 * cache lines 1-3 for syscalls. 391 * 392 * cache line 8: ptregs padding (two words) 393 * cache line 7: sp, lr, pc, ex1, faultnum, orig_r0, flags, cmpexch 394 * cache line 6: r46...r53 (tp) 395 * cache line 5: r38...r45 396 * cache line 4: r30...r37 397 * cache line 3: r22...r29 398 * cache line 2: r14...r21 399 * cache line 1: r6...r13 400 * cache line 0: 2 x frame, r0..r5 401 */ 402#if STACK_TOP_DELTA != 64 403#error STACK_TOP_DELTA must be 64 for assumptions here and in task_pt_regs() 404#endif 405 andi r0, r0, -64 406 407 /* 408 * Push the first four registers on the stack, so that we can set 409 * them to vector-unique values before we jump to the common code. 410 * 411 * Registers are pushed on the stack as a struct pt_regs, 412 * with the sp initially just above the struct, and when we're 413 * done, sp points to the base of the struct, minus 414 * C_ABI_SAVE_AREA_SIZE, so we can directly jal to C code. 415 * 416 * This routine saves just the first four registers, plus the 417 * stack context so we can do proper backtracing right away, 418 * and defers to handle_interrupt to save the rest. 419 * The backtracer needs pc, ex1, lr, sp, r52, and faultnum, 420 * and needs sp set to its final location at the bottom of 421 * the stack frame. 422 */ 423 addli r0, r0, PTREGS_OFFSET_LR - (PTREGS_SIZE + KSTK_PTREGS_GAP) 424 wh64 r0 /* cache line 7 */ 425 { 426 st r0, lr 427 addli r0, r0, PTREGS_OFFSET_SP - PTREGS_OFFSET_LR 428 } 429 { 430 st r0, sp 431 addli sp, r0, PTREGS_OFFSET_REG(52) - PTREGS_OFFSET_SP 432 } 433 wh64 sp /* cache line 6 */ 434 { 435 st sp, r52 436 addli sp, sp, PTREGS_OFFSET_REG(1) - PTREGS_OFFSET_REG(52) 437 } 438 wh64 sp /* cache line 0 */ 439 { 440 st sp, r1 441 addli sp, sp, PTREGS_OFFSET_REG(2) - PTREGS_OFFSET_REG(1) 442 } 443 { 444 st sp, r2 445 addli sp, sp, PTREGS_OFFSET_REG(3) - PTREGS_OFFSET_REG(2) 446 } 447 { 448 st sp, r3 449 addli sp, sp, PTREGS_OFFSET_PC - PTREGS_OFFSET_REG(3) 450 } 451 mfspr r0, SPR_EX_CONTEXT_K_0 452 .ifc \processing,handle_syscall 453 /* 454 * Bump the saved PC by one bundle so that when we return, we won't 455 * execute the same swint instruction again. We need to do this while 456 * we're in the critical section. 457 */ 458 addi r0, r0, 8 459 .endif 460 { 461 st sp, r0 462 addli sp, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_PC 463 } 464 mfspr r0, SPR_EX_CONTEXT_K_1 465 { 466 st sp, r0 467 addi sp, sp, PTREGS_OFFSET_FAULTNUM - PTREGS_OFFSET_EX1 468 /* 469 * Use r0 for syscalls so it's a temporary; use r1 for interrupts 470 * so that it gets passed through unchanged to the handler routine. 471 * Note that the .if conditional confusingly spans bundles. 472 */ 473 .ifc \processing,handle_syscall 474 movei r0, \vecnum 475 } 476 { 477 st sp, r0 478 .else 479 movei r1, \vecnum 480 } 481 { 482 st sp, r1 483 .endif 484 addli sp, sp, PTREGS_OFFSET_REG(0) - PTREGS_OFFSET_FAULTNUM 485 } 486 mfspr r0, SPR_SYSTEM_SAVE_K_1 /* Original r0 */ 487 { 488 st sp, r0 489 addi sp, sp, -PTREGS_OFFSET_REG(0) - 8 490 } 491 { 492 st sp, zero /* write zero into "Next SP" frame pointer */ 493 addi sp, sp, -8 /* leave SP pointing at bottom of frame */ 494 } 495 .ifc \processing,handle_syscall 496 j handle_syscall 497 .else 498 /* Capture per-interrupt SPR context to registers. */ 499 .ifc \c_routine, do_page_fault 500 mfspr r2, SPR_SYSTEM_SAVE_K_3 /* address of page fault */ 501 mfspr r3, SPR_SYSTEM_SAVE_K_2 /* info about page fault */ 502 .else 503 .ifc \vecnum, INT_ILL_TRANS 504 mfspr r2, ILL_VA_PC 505 .else 506 .ifc \vecnum, INT_DOUBLE_FAULT 507 mfspr r2, SPR_SYSTEM_SAVE_K_2 /* double fault info from HV */ 508 .else 509 .ifc \c_routine, do_trap 510 mfspr r2, GPV_REASON 511 .else 512 .ifc \c_routine, handle_perf_interrupt 513 mfspr r2, PERF_COUNT_STS 514 .else 515 .ifc \c_routine, handle_perf_interrupt 516 mfspr r2, AUX_PERF_COUNT_STS 517 .endif 518 .ifc \c_routine, do_nmi 519 mfspr r2, SPR_SYSTEM_SAVE_K_2 /* nmi type */ 520 .else 521 .endif 522 .endif 523 .endif 524 .endif 525 .endif 526 .endif 527 /* Put function pointer in r0 */ 528 moveli r0, hw2_last(\c_routine) 529 shl16insli r0, r0, hw1(\c_routine) 530 { 531 shl16insli r0, r0, hw0(\c_routine) 532 j \processing 533 } 534 .endif 535 ENDPROC(intvec_\vecname) 536 537#ifdef __COLLECT_LINKER_FEEDBACK__ 538 .pushsection .text.intvec_feedback,"ax" 539 .org (\vecnum << 5) 540 FEEDBACK_ENTER_EXPLICIT(intvec_\vecname, .intrpt, 1 << 8) 541 jrp lr 542 .popsection 543#endif 544 545 .endm 546 547 548 /* 549 * Save the rest of the registers that we didn't save in the actual 550 * vector itself. We can't use r0-r10 inclusive here. 551 */ 552 .macro finish_interrupt_save, function 553 554 /* If it's a syscall, save a proper orig_r0, otherwise just zero. */ 555 PTREGS_PTR(r52, PTREGS_OFFSET_ORIG_R0) 556 { 557 .ifc \function,handle_syscall 558 st r52, r0 559 .else 560 st r52, zero 561 .endif 562 PTREGS_PTR(r52, PTREGS_OFFSET_TP) 563 } 564 st r52, tp 565 { 566 mfspr tp, CMPEXCH_VALUE 567 PTREGS_PTR(r52, PTREGS_OFFSET_CMPEXCH) 568 } 569 570 /* 571 * For ordinary syscalls, we save neither caller- nor callee- 572 * save registers, since the syscall invoker doesn't expect the 573 * caller-saves to be saved, and the called kernel functions will 574 * take care of saving the callee-saves for us. 575 * 576 * For interrupts we save just the caller-save registers. Saving 577 * them is required (since the "caller" can't save them). Again, 578 * the called kernel functions will restore the callee-save 579 * registers for us appropriately. 580 * 581 * On return, we normally restore nothing special for syscalls, 582 * and just the caller-save registers for interrupts. 583 * 584 * However, there are some important caveats to all this: 585 * 586 * - We always save a few callee-save registers to give us 587 * some scratchpad registers to carry across function calls. 588 * 589 * - fork/vfork/etc require us to save all the callee-save 590 * registers, which we do in PTREGS_SYSCALL_ALL_REGS, below. 591 * 592 * - We always save r0..r5 and r10 for syscalls, since we need 593 * to reload them a bit later for the actual kernel call, and 594 * since we might need them for -ERESTARTNOINTR, etc. 595 * 596 * - Before invoking a signal handler, we save the unsaved 597 * callee-save registers so they are visible to the 598 * signal handler or any ptracer. 599 * 600 * - If the unsaved callee-save registers are modified, we set 601 * a bit in pt_regs so we know to reload them from pt_regs 602 * and not just rely on the kernel function unwinding. 603 * (Done for ptrace register writes and SA_SIGINFO handler.) 604 */ 605 { 606 st r52, tp 607 PTREGS_PTR(r52, PTREGS_OFFSET_REG(33)) 608 } 609 wh64 r52 /* cache line 4 */ 610 push_reg r33, r52 611 push_reg r32, r52 612 push_reg r31, r52 613 .ifc \function,handle_syscall 614 push_reg r30, r52, PTREGS_OFFSET_SYSCALL - PTREGS_OFFSET_REG(30) 615 push_reg TREG_SYSCALL_NR_NAME, r52, \ 616 PTREGS_OFFSET_REG(5) - PTREGS_OFFSET_SYSCALL 617 .else 618 619 push_reg r30, r52, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(30) 620 wh64 r52 /* cache line 3 */ 621 push_reg r29, r52 622 push_reg r28, r52 623 push_reg r27, r52 624 push_reg r26, r52 625 push_reg r25, r52 626 push_reg r24, r52 627 push_reg r23, r52 628 push_reg r22, r52 629 wh64 r52 /* cache line 2 */ 630 push_reg r21, r52 631 push_reg r20, r52 632 push_reg r19, r52 633 push_reg r18, r52 634 push_reg r17, r52 635 push_reg r16, r52 636 push_reg r15, r52 637 push_reg r14, r52 638 wh64 r52 /* cache line 1 */ 639 push_reg r13, r52 640 push_reg r12, r52 641 push_reg r11, r52 642 push_reg r10, r52 643 push_reg r9, r52 644 push_reg r8, r52 645 push_reg r7, r52 646 push_reg r6, r52 647 648 .endif 649 650 push_reg r5, r52 651 st r52, r4 652 653 /* 654 * If we will be returning to the kernel, we will need to 655 * reset the interrupt masks to the state they had before. 656 * Set DISABLE_IRQ in flags iff we came from kernel pl with 657 * irqs disabled. 658 */ 659 mfspr r32, SPR_EX_CONTEXT_K_1 660 { 661 IS_KERNEL_EX1(r32, r32) 662 PTREGS_PTR(r21, PTREGS_OFFSET_FLAGS) 663 } 664 beqzt r32, 1f /* zero if from user space */ 665 IRQS_DISABLED(r32) /* zero if irqs enabled */ 666#if PT_FLAGS_DISABLE_IRQ != 1 667# error Value of IRQS_DISABLED used to set PT_FLAGS_DISABLE_IRQ; fix 668#endif 6691: 670 .ifnc \function,handle_syscall 671 /* Record the fact that we saved the caller-save registers above. */ 672 ori r32, r32, PT_FLAGS_CALLER_SAVES 673 .endif 674 st r21, r32 675 676 /* 677 * we've captured enough state to the stack (including in 678 * particular our EX_CONTEXT state) that we can now release 679 * the interrupt critical section and replace it with our 680 * standard "interrupts disabled" mask value. This allows 681 * synchronous interrupts (and profile interrupts) to punch 682 * through from this point onwards. 683 * 684 * It's important that no code before this point touch memory 685 * other than our own stack (to keep the invariant that this 686 * is all that gets touched under ICS), and that no code after 687 * this point reference any interrupt-specific SPR, in particular 688 * the EX_CONTEXT_K_ values. 689 */ 690 .ifc \function,handle_nmi 691 IRQ_DISABLE_ALL(r20) 692 .else 693 IRQ_DISABLE(r20, r21) 694 .endif 695 mtspr INTERRUPT_CRITICAL_SECTION, zero 696 697 /* Load tp with our per-cpu offset. */ 698#ifdef CONFIG_SMP 699 { 700 mfspr r20, SPR_SYSTEM_SAVE_K_0 701 moveli r21, hw2_last(__per_cpu_offset) 702 } 703 { 704 shl16insli r21, r21, hw1(__per_cpu_offset) 705 bfextu r20, r20, CPU_SHIFT, 63 706 } 707 shl16insli r21, r21, hw0(__per_cpu_offset) 708 shl3add r20, r20, r21 709 ld tp, r20 710#else 711 move tp, zero 712#endif 713 714#ifdef __COLLECT_LINKER_FEEDBACK__ 715 /* 716 * Notify the feedback routines that we were in the 717 * appropriate fixed interrupt vector area. Note that we 718 * still have ICS set at this point, so we can't invoke any 719 * atomic operations or we will panic. The feedback 720 * routines internally preserve r0..r10 and r30 up. 721 */ 722 .ifnc \function,handle_syscall 723 shli r20, r1, 5 724 .else 725 moveli r20, INT_SWINT_1 << 5 726 .endif 727 moveli r21, hw2_last(intvec_feedback) 728 shl16insli r21, r21, hw1(intvec_feedback) 729 shl16insli r21, r21, hw0(intvec_feedback) 730 add r20, r20, r21 731 jalr r20 732 733 /* And now notify the feedback routines that we are here. */ 734 FEEDBACK_ENTER(\function) 735#endif 736 737 /* 738 * Prepare the first 256 stack bytes to be rapidly accessible 739 * without having to fetch the background data. 740 */ 741 addi r52, sp, -64 742 { 743 wh64 r52 744 addi r52, r52, -64 745 } 746 { 747 wh64 r52 748 addi r52, r52, -64 749 } 750 { 751 wh64 r52 752 addi r52, r52, -64 753 } 754 wh64 r52 755 756#if defined(CONFIG_TRACE_IRQFLAGS) || defined(CONFIG_CONTEXT_TRACKING) 757 .ifnc \function,handle_nmi 758 /* 759 * We finally have enough state set up to notify the irq 760 * tracing code that irqs were disabled on entry to the handler. 761 * The TRACE_IRQS_OFF call clobbers registers r0-r29. 762 * For syscalls, we already have the register state saved away 763 * on the stack, so we don't bother to do any register saves here, 764 * and later we pop the registers back off the kernel stack. 765 * For interrupt handlers, save r0-r3 in callee-saved registers. 766 */ 767 .ifnc \function,handle_syscall 768 { move r30, r0; move r31, r1 } 769 { move r32, r2; move r33, r3 } 770 .endif 771 TRACE_IRQS_OFF 772#ifdef CONFIG_CONTEXT_TRACKING 773 jal context_tracking_user_exit 774#endif 775 .ifnc \function,handle_syscall 776 { move r0, r30; move r1, r31 } 777 { move r2, r32; move r3, r33 } 778 .endif 779 .endif 780#endif 781 782 .endm 783 784 /* 785 * Redispatch a downcall. 786 */ 787 .macro dc_dispatch vecnum, vecname 788 .org (\vecnum << 8) 789intvec_\vecname: 790 j _hv_downcall_dispatch 791 ENDPROC(intvec_\vecname) 792 .endm 793 794 /* 795 * Common code for most interrupts. The C function we're eventually 796 * going to is in r0, and the faultnum is in r1; the original 797 * values for those registers are on the stack. 798 */ 799 .pushsection .text.handle_interrupt,"ax" 800handle_interrupt: 801 finish_interrupt_save handle_interrupt 802 803 /* Jump to the C routine; it should enable irqs as soon as possible. */ 804 { 805 jalr r0 806 PTREGS_PTR(r0, PTREGS_OFFSET_BASE) 807 } 808 FEEDBACK_REENTER(handle_interrupt) 809 { 810 movei r30, 0 /* not an NMI */ 811 j interrupt_return 812 } 813 STD_ENDPROC(handle_interrupt) 814 815/* 816 * This routine takes a boolean in r30 indicating if this is an NMI. 817 * If so, we also expect a boolean in r31 indicating whether to 818 * re-enable the oprofile interrupts. 819 * 820 * Note that .Lresume_userspace is jumped to directly in several 821 * places, and we need to make sure r30 is set correctly in those 822 * callers as well. 823 */ 824STD_ENTRY(interrupt_return) 825 /* If we're resuming to kernel space, don't check thread flags. */ 826 { 827 bnez r30, .Lrestore_all /* NMIs don't special-case user-space */ 828 PTREGS_PTR(r29, PTREGS_OFFSET_EX1) 829 } 830 ld r29, r29 831 IS_KERNEL_EX1(r29, r29) 832 { 833 beqzt r29, .Lresume_userspace 834 move r29, sp 835 } 836 837#ifdef CONFIG_PREEMPT 838 /* Returning to kernel space. Check if we need preemption. */ 839 EXTRACT_THREAD_INFO(r29) 840 addli r28, r29, THREAD_INFO_FLAGS_OFFSET 841 { 842 ld r28, r28 843 addli r29, r29, THREAD_INFO_PREEMPT_COUNT_OFFSET 844 } 845 { 846 andi r28, r28, _TIF_NEED_RESCHED 847 ld4s r29, r29 848 } 849 beqzt r28, 1f 850 bnez r29, 1f 851 /* Disable interrupts explicitly for preemption. */ 852 IRQ_DISABLE(r20,r21) 853 TRACE_IRQS_OFF 854 jal preempt_schedule_irq 855 FEEDBACK_REENTER(interrupt_return) 8561: 857#endif 858 859 /* If we're resuming to _cpu_idle_nap, bump PC forward by 8. */ 860 { 861 moveli r27, hw2_last(_cpu_idle_nap) 862 PTREGS_PTR(r29, PTREGS_OFFSET_PC) 863 } 864 { 865 ld r28, r29 866 shl16insli r27, r27, hw1(_cpu_idle_nap) 867 } 868 { 869 shl16insli r27, r27, hw0(_cpu_idle_nap) 870 } 871 { 872 cmpeq r27, r27, r28 873 } 874 { 875 blbc r27, .Lrestore_all 876 addi r28, r28, 8 877 } 878 st r29, r28 879 j .Lrestore_all 880 881.Lresume_userspace: 882 FEEDBACK_REENTER(interrupt_return) 883 884 /* 885 * Disable interrupts so as to make sure we don't 886 * miss an interrupt that sets any of the thread flags (like 887 * need_resched or sigpending) between sampling and the iret. 888 * Routines like schedule() or do_signal() may re-enable 889 * interrupts before returning. 890 */ 891 IRQ_DISABLE(r20, r21) 892 TRACE_IRQS_OFF /* Note: clobbers registers r0-r29 */ 893 894 /* 895 * See if there are any work items (including single-shot items) 896 * to do. If so, save the callee-save registers to pt_regs 897 * and then dispatch to C code. 898 */ 899 move r21, sp 900 EXTRACT_THREAD_INFO(r21) 901 { 902 addi r22, r21, THREAD_INFO_FLAGS_OFFSET 903 moveli r20, hw1_last(_TIF_ALLWORK_MASK) 904 } 905 { 906 ld r22, r22 907 shl16insli r20, r20, hw0(_TIF_ALLWORK_MASK) 908 } 909 and r1, r22, r20 910 { 911 PTREGS_PTR(r0, PTREGS_OFFSET_BASE) 912 beqzt r1, .Lrestore_all 913 } 914 push_extra_callee_saves r0 915 jal prepare_exit_to_usermode 916 917 /* 918 * In the NMI case we 919 * omit the call to single_process_check_nohz, which normally checks 920 * to see if we should start or stop the scheduler tick, because 921 * we can't call arbitrary Linux code from an NMI context. 922 * We always call the homecache TLB deferral code to re-trigger 923 * the deferral mechanism. 924 * 925 * The other chunk of responsibility this code has is to reset the 926 * interrupt masks appropriately to reset irqs and NMIs. We have 927 * to call TRACE_IRQS_OFF and TRACE_IRQS_ON to support all the 928 * lockdep-type stuff, but we can't set ICS until afterwards, since 929 * ICS can only be used in very tight chunks of code to avoid 930 * tripping over various assertions that it is off. 931 */ 932.Lrestore_all: 933 PTREGS_PTR(r0, PTREGS_OFFSET_EX1) 934 { 935 ld r0, r0 936 PTREGS_PTR(r32, PTREGS_OFFSET_FLAGS) 937 } 938 { 939 IS_KERNEL_EX1(r0, r0) 940 ld r32, r32 941 } 942 bnez r0, 1f 943 j 2f 944#if PT_FLAGS_DISABLE_IRQ != 1 945# error Assuming PT_FLAGS_DISABLE_IRQ == 1 so we can use blbct below 946#endif 9471: blbct r32, 2f 948 IRQ_DISABLE(r20,r21) 949 TRACE_IRQS_OFF 950 movei r0, 1 951 mtspr INTERRUPT_CRITICAL_SECTION, r0 952 beqzt r30, .Lrestore_regs 953 j 3f 9542: TRACE_IRQS_ON 955 IRQ_ENABLE_LOAD(r20, r21) 956 movei r0, 1 957 mtspr INTERRUPT_CRITICAL_SECTION, r0 958 IRQ_ENABLE_APPLY(r20, r21) 959 beqzt r30, .Lrestore_regs 9603: 961 962#if INT_PERF_COUNT + 1 != INT_AUX_PERF_COUNT 963# error Bad interrupt assumption 964#endif 965 { 966 movei r0, 3 /* two adjacent bits for the PERF_COUNT mask */ 967 beqz r31, .Lrestore_regs 968 } 969 shli r0, r0, INT_PERF_COUNT 970 mtspr SPR_INTERRUPT_MASK_RESET_K, r0 971 972 /* 973 * We now commit to returning from this interrupt, since we will be 974 * doing things like setting EX_CONTEXT SPRs and unwinding the stack 975 * frame. No calls should be made to any other code after this point. 976 * This code should only be entered with ICS set. 977 * r32 must still be set to ptregs.flags. 978 * We launch loads to each cache line separately first, so we can 979 * get some parallelism out of the memory subsystem. 980 * We start zeroing caller-saved registers throughout, since 981 * that will save some cycles if this turns out to be a syscall. 982 */ 983.Lrestore_regs: 984 985 /* 986 * Rotate so we have one high bit and one low bit to test. 987 * - low bit says whether to restore all the callee-saved registers, 988 * or just r30-r33, and r52 up. 989 * - high bit (i.e. sign bit) says whether to restore all the 990 * caller-saved registers, or just r0. 991 */ 992#if PT_FLAGS_CALLER_SAVES != 2 || PT_FLAGS_RESTORE_REGS != 4 993# error Rotate trick does not work :-) 994#endif 995 { 996 rotli r20, r32, 62 997 PTREGS_PTR(sp, PTREGS_OFFSET_REG(0)) 998 } 999 1000 /* 1001 * Load cache lines 0, 4, 6 and 7, in that order, then use 1002 * the last loaded value, which makes it likely that the other 1003 * cache lines have also loaded, at which point we should be 1004 * able to safely read all the remaining words on those cache 1005 * lines without waiting for the memory subsystem. 1006 */ 1007 pop_reg r0, sp, PTREGS_OFFSET_REG(30) - PTREGS_OFFSET_REG(0) 1008 pop_reg r30, sp, PTREGS_OFFSET_REG(52) - PTREGS_OFFSET_REG(30) 1009 pop_reg_zero r52, r3, sp, PTREGS_OFFSET_CMPEXCH - PTREGS_OFFSET_REG(52) 1010 pop_reg_zero r21, r27, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_CMPEXCH 1011 pop_reg_zero lr, r2, sp, PTREGS_OFFSET_PC - PTREGS_OFFSET_EX1 1012 { 1013 mtspr CMPEXCH_VALUE, r21 1014 move r4, zero 1015 } 1016 pop_reg r21, sp, PTREGS_OFFSET_REG(31) - PTREGS_OFFSET_PC 1017 { 1018 mtspr SPR_EX_CONTEXT_K_1, lr 1019 IS_KERNEL_EX1(lr, lr) 1020 } 1021 { 1022 mtspr SPR_EX_CONTEXT_K_0, r21 1023 move r5, zero 1024 } 1025 1026 /* Restore callee-saveds that we actually use. */ 1027 pop_reg_zero r31, r6 1028 pop_reg_zero r32, r7 1029 pop_reg_zero r33, r8, sp, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(33) 1030 1031 /* 1032 * If we modified other callee-saveds, restore them now. 1033 * This is rare, but could be via ptrace or signal handler. 1034 */ 1035 { 1036 move r9, zero 1037 blbs r20, .Lrestore_callees 1038 } 1039.Lcontinue_restore_regs: 1040 1041 /* Check if we're returning from a syscall. */ 1042 { 1043 move r10, zero 1044 bltzt r20, 1f /* no, so go restore callee-save registers */ 1045 } 1046 1047 /* 1048 * Check if we're returning to userspace. 1049 * Note that if we're not, we don't worry about zeroing everything. 1050 */ 1051 { 1052 addli sp, sp, PTREGS_OFFSET_LR - PTREGS_OFFSET_REG(29) 1053 bnez lr, .Lkernel_return 1054 } 1055 1056 /* 1057 * On return from syscall, we've restored r0 from pt_regs, but we 1058 * clear the remainder of the caller-saved registers. We could 1059 * restore the syscall arguments, but there's not much point, 1060 * and it ensures user programs aren't trying to use the 1061 * caller-saves if we clear them, as well as avoiding leaking 1062 * kernel pointers into userspace. 1063 */ 1064 pop_reg_zero lr, r11, sp, PTREGS_OFFSET_TP - PTREGS_OFFSET_LR 1065 pop_reg_zero tp, r12, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_TP 1066 { 1067 ld sp, sp 1068 move r13, zero 1069 move r14, zero 1070 } 1071 { move r15, zero; move r16, zero } 1072 { move r17, zero; move r18, zero } 1073 { move r19, zero; move r20, zero } 1074 { move r21, zero; move r22, zero } 1075 { move r23, zero; move r24, zero } 1076 { move r25, zero; move r26, zero } 1077 1078 /* Set r1 to errno if we are returning an error, otherwise zero. */ 1079 { 1080 moveli r29, 4096 1081 sub r1, zero, r0 1082 } 1083 { 1084 move r28, zero 1085 cmpltu r29, r1, r29 1086 } 1087 { 1088 mnz r1, r29, r1 1089 move r29, zero 1090 } 1091 iret 1092 1093 /* 1094 * Not a syscall, so restore caller-saved registers. 1095 * First kick off loads for cache lines 1-3, which we're touching 1096 * for the first time here. 1097 */ 1098 .align 64 10991: pop_reg r29, sp, PTREGS_OFFSET_REG(21) - PTREGS_OFFSET_REG(29) 1100 pop_reg r21, sp, PTREGS_OFFSET_REG(13) - PTREGS_OFFSET_REG(21) 1101 pop_reg r13, sp, PTREGS_OFFSET_REG(1) - PTREGS_OFFSET_REG(13) 1102 pop_reg r1 1103 pop_reg r2 1104 pop_reg r3 1105 pop_reg r4 1106 pop_reg r5 1107 pop_reg r6 1108 pop_reg r7 1109 pop_reg r8 1110 pop_reg r9 1111 pop_reg r10 1112 pop_reg r11 1113 pop_reg r12, sp, 16 1114 /* r13 already restored above */ 1115 pop_reg r14 1116 pop_reg r15 1117 pop_reg r16 1118 pop_reg r17 1119 pop_reg r18 1120 pop_reg r19 1121 pop_reg r20, sp, 16 1122 /* r21 already restored above */ 1123 pop_reg r22 1124 pop_reg r23 1125 pop_reg r24 1126 pop_reg r25 1127 pop_reg r26 1128 pop_reg r27 1129 pop_reg r28, sp, PTREGS_OFFSET_LR - PTREGS_OFFSET_REG(28) 1130 /* r29 already restored above */ 1131 bnez lr, .Lkernel_return 1132 pop_reg lr, sp, PTREGS_OFFSET_TP - PTREGS_OFFSET_LR 1133 pop_reg tp, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_TP 1134 ld sp, sp 1135 iret 1136 1137 /* 1138 * We can't restore tp when in kernel mode, since a thread might 1139 * have migrated from another cpu and brought a stale tp value. 1140 */ 1141.Lkernel_return: 1142 pop_reg lr, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_LR 1143 ld sp, sp 1144 iret 1145 1146 /* Restore callee-saved registers from r34 to r51. */ 1147.Lrestore_callees: 1148 addli sp, sp, PTREGS_OFFSET_REG(34) - PTREGS_OFFSET_REG(29) 1149 pop_reg r34 1150 pop_reg r35 1151 pop_reg r36 1152 pop_reg r37 1153 pop_reg r38 1154 pop_reg r39 1155 pop_reg r40 1156 pop_reg r41 1157 pop_reg r42 1158 pop_reg r43 1159 pop_reg r44 1160 pop_reg r45 1161 pop_reg r46 1162 pop_reg r47 1163 pop_reg r48 1164 pop_reg r49 1165 pop_reg r50 1166 pop_reg r51, sp, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(51) 1167 j .Lcontinue_restore_regs 1168 STD_ENDPROC(interrupt_return) 1169 1170 /* 1171 * "NMI" interrupts mask ALL interrupts before calling the 1172 * handler, and don't check thread flags, etc., on the way 1173 * back out. In general, the only things we do here for NMIs 1174 * are register save/restore and dataplane kernel-TLB management. 1175 * We don't (for example) deal with start/stop of the sched tick. 1176 */ 1177 .pushsection .text.handle_nmi,"ax" 1178handle_nmi: 1179 finish_interrupt_save handle_nmi 1180 { 1181 jalr r0 1182 PTREGS_PTR(r0, PTREGS_OFFSET_BASE) 1183 } 1184 FEEDBACK_REENTER(handle_nmi) 1185 { 1186 movei r30, 1 1187 cmpeq r31, r0, zero 1188 } 1189 j interrupt_return 1190 STD_ENDPROC(handle_nmi) 1191 1192 /* 1193 * Parallel code for syscalls to handle_interrupt. 1194 */ 1195 .pushsection .text.handle_syscall,"ax" 1196handle_syscall: 1197 finish_interrupt_save handle_syscall 1198 1199 /* Enable irqs. */ 1200 TRACE_IRQS_ON 1201 IRQ_ENABLE(r20, r21) 1202 1203 /* Bump the counter for syscalls made on this tile. */ 1204 moveli r20, hw2_last(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET) 1205 shl16insli r20, r20, hw1(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET) 1206 shl16insli r20, r20, hw0(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET) 1207 add r20, r20, tp 1208 ld4s r21, r20 1209 { 1210 addi r21, r21, 1 1211 move r31, sp 1212 } 1213 { 1214 st4 r20, r21 1215 EXTRACT_THREAD_INFO(r31) 1216 } 1217 1218 /* Trace syscalls, if requested. */ 1219 addi r31, r31, THREAD_INFO_FLAGS_OFFSET 1220 { 1221 ld r30, r31 1222 moveli r32, _TIF_SYSCALL_ENTRY_WORK 1223 } 1224 and r30, r30, r32 1225 { 1226 addi r30, r31, THREAD_INFO_STATUS_OFFSET - THREAD_INFO_FLAGS_OFFSET 1227 beqzt r30, .Lrestore_syscall_regs 1228 } 1229 { 1230 PTREGS_PTR(r0, PTREGS_OFFSET_BASE) 1231 jal do_syscall_trace_enter 1232 } 1233 FEEDBACK_REENTER(handle_syscall) 1234 bltz r0, .Lsyscall_sigreturn_skip 1235 1236 /* 1237 * We always reload our registers from the stack at this 1238 * point. They might be valid, if we didn't build with 1239 * TRACE_IRQFLAGS, and this isn't a dataplane tile, and we're not 1240 * doing syscall tracing, but there are enough cases now that it 1241 * seems simplest just to do the reload unconditionally. 1242 */ 1243.Lrestore_syscall_regs: 1244 { 1245 ld r30, r30 1246 PTREGS_PTR(r11, PTREGS_OFFSET_REG(0)) 1247 } 1248 pop_reg r0, r11 1249 pop_reg r1, r11 1250 pop_reg r2, r11 1251 pop_reg r3, r11 1252 pop_reg r4, r11 1253 pop_reg r5, r11, PTREGS_OFFSET_SYSCALL - PTREGS_OFFSET_REG(5) 1254 { 1255 ld TREG_SYSCALL_NR_NAME, r11 1256 moveli r21, __NR_syscalls 1257 } 1258 1259 /* Ensure that the syscall number is within the legal range. */ 1260 { 1261 moveli r20, hw2(sys_call_table) 1262#ifdef CONFIG_COMPAT 1263 blbs r30, .Lcompat_syscall 1264#endif 1265 } 1266 { 1267 cmpltu r21, TREG_SYSCALL_NR_NAME, r21 1268 shl16insli r20, r20, hw1(sys_call_table) 1269 } 1270 { 1271 blbc r21, .Linvalid_syscall 1272 shl16insli r20, r20, hw0(sys_call_table) 1273 } 1274.Lload_syscall_pointer: 1275 shl3add r20, TREG_SYSCALL_NR_NAME, r20 1276 ld r20, r20 1277 1278 /* Jump to syscall handler. */ 1279 jalr r20 1280.Lhandle_syscall_link: /* value of "lr" after "jalr r20" above */ 1281 1282 /* 1283 * Write our r0 onto the stack so it gets restored instead 1284 * of whatever the user had there before. 1285 * In compat mode, sign-extend r0 before storing it. 1286 */ 1287 { 1288 PTREGS_PTR(r29, PTREGS_OFFSET_REG(0)) 1289 blbct r30, 1f 1290 } 1291 addxi r0, r0, 0 12921: st r29, r0 1293 1294.Lsyscall_sigreturn_skip: 1295 FEEDBACK_REENTER(handle_syscall) 1296 1297 /* Do syscall trace again, if requested. */ 1298 { 1299 ld r30, r31 1300 moveli r32, _TIF_SYSCALL_EXIT_WORK 1301 } 1302 and r0, r30, r32 1303 { 1304 andi r0, r30, _TIF_SINGLESTEP 1305 beqzt r0, 1f 1306 } 1307 { 1308 PTREGS_PTR(r0, PTREGS_OFFSET_BASE) 1309 jal do_syscall_trace_exit 1310 } 1311 FEEDBACK_REENTER(handle_syscall) 1312 andi r0, r30, _TIF_SINGLESTEP 1313 13141: beqzt r0, 2f 1315 1316 /* Single stepping -- notify ptrace. */ 1317 { 1318 movei r0, SIGTRAP 1319 jal ptrace_notify 1320 } 1321 FEEDBACK_REENTER(handle_syscall) 1322 13232: { 1324 movei r30, 0 /* not an NMI */ 1325 j .Lresume_userspace /* jump into middle of interrupt_return */ 1326 } 1327 1328#ifdef CONFIG_COMPAT 1329.Lcompat_syscall: 1330 /* 1331 * Load the base of the compat syscall table in r20, and 1332 * range-check the syscall number (duplicated from 64-bit path). 1333 * Sign-extend all the user's passed arguments to make them consistent. 1334 * Also save the original "r(n)" values away in "r(11+n)" in 1335 * case the syscall table entry wants to validate them. 1336 */ 1337 moveli r20, hw2(compat_sys_call_table) 1338 { 1339 cmpltu r21, TREG_SYSCALL_NR_NAME, r21 1340 shl16insli r20, r20, hw1(compat_sys_call_table) 1341 } 1342 { 1343 blbc r21, .Linvalid_syscall 1344 shl16insli r20, r20, hw0(compat_sys_call_table) 1345 } 1346 { move r11, r0; addxi r0, r0, 0 } 1347 { move r12, r1; addxi r1, r1, 0 } 1348 { move r13, r2; addxi r2, r2, 0 } 1349 { move r14, r3; addxi r3, r3, 0 } 1350 { move r15, r4; addxi r4, r4, 0 } 1351 { move r16, r5; addxi r5, r5, 0 } 1352 j .Lload_syscall_pointer 1353#endif 1354 1355.Linvalid_syscall: 1356 /* Report an invalid syscall back to the user program */ 1357 { 1358 PTREGS_PTR(r29, PTREGS_OFFSET_REG(0)) 1359 movei r28, -ENOSYS 1360 } 1361 st r29, r28 1362 { 1363 movei r30, 0 /* not an NMI */ 1364 j .Lresume_userspace /* jump into middle of interrupt_return */ 1365 } 1366 STD_ENDPROC(handle_syscall) 1367 1368 /* Return the address for oprofile to suppress in backtraces. */ 1369STD_ENTRY_SECTION(handle_syscall_link_address, .text.handle_syscall) 1370 lnk r0 1371 { 1372 addli r0, r0, .Lhandle_syscall_link - . 1373 jrp lr 1374 } 1375 STD_ENDPROC(handle_syscall_link_address) 1376 1377STD_ENTRY(ret_from_fork) 1378 jal sim_notify_fork 1379 jal schedule_tail 1380 FEEDBACK_REENTER(ret_from_fork) 1381 { 1382 movei r30, 0 /* not an NMI */ 1383 j .Lresume_userspace /* jump into middle of interrupt_return */ 1384 } 1385 STD_ENDPROC(ret_from_fork) 1386 1387STD_ENTRY(ret_from_kernel_thread) 1388 jal sim_notify_fork 1389 jal schedule_tail 1390 FEEDBACK_REENTER(ret_from_fork) 1391 { 1392 move r0, r31 1393 jalr r30 1394 } 1395 FEEDBACK_REENTER(ret_from_kernel_thread) 1396 { 1397 movei r30, 0 /* not an NMI */ 1398 j interrupt_return 1399 } 1400 STD_ENDPROC(ret_from_kernel_thread) 1401 1402/* Various stub interrupt handlers and syscall handlers */ 1403 1404STD_ENTRY_LOCAL(_kernel_double_fault) 1405 mfspr r1, SPR_EX_CONTEXT_K_0 1406 move r2, lr 1407 move r3, sp 1408 move r4, r52 1409 addi sp, sp, -C_ABI_SAVE_AREA_SIZE 1410 j kernel_double_fault 1411 STD_ENDPROC(_kernel_double_fault) 1412 1413STD_ENTRY_LOCAL(bad_intr) 1414 mfspr r2, SPR_EX_CONTEXT_K_0 1415 panic "Unhandled interrupt %#x: PC %#lx" 1416 STD_ENDPROC(bad_intr) 1417 1418/* 1419 * Special-case sigreturn to not write r0 to the stack on return. 1420 * This is technically more efficient, but it also avoids difficulties 1421 * in the 64-bit OS when handling 32-bit compat code, since we must not 1422 * sign-extend r0 for the sigreturn return-value case. 1423 */ 1424#define PTREGS_SYSCALL_SIGRETURN(x, reg) \ 1425 STD_ENTRY(_##x); \ 1426 addli lr, lr, .Lsyscall_sigreturn_skip - .Lhandle_syscall_link; \ 1427 { \ 1428 PTREGS_PTR(reg, PTREGS_OFFSET_BASE); \ 1429 j x \ 1430 }; \ 1431 STD_ENDPROC(_##x) 1432 1433PTREGS_SYSCALL_SIGRETURN(sys_rt_sigreturn, r0) 1434#ifdef CONFIG_COMPAT 1435PTREGS_SYSCALL_SIGRETURN(compat_sys_rt_sigreturn, r0) 1436#endif 1437 1438/* Save additional callee-saves to pt_regs and jump to standard function. */ 1439STD_ENTRY(_sys_clone) 1440 push_extra_callee_saves r4 1441 j sys_clone 1442 STD_ENDPROC(_sys_clone) 1443 1444 /* 1445 * Recover r3, r2, r1 and r0 here saved by unalign fast vector. 1446 * The vector area limit is 32 bundles, so we handle the reload here. 1447 * r0, r1, r2 are in thread_info from low to high memory in order. 1448 * r3 points to location the original r3 was saved. 1449 * We put this code in the __HEAD section so it can be reached 1450 * via a conditional branch from the fast path. 1451 */ 1452 __HEAD 1453hand_unalign_slow: 1454 andi sp, sp, ~1 1455hand_unalign_slow_badsp: 1456 addi r3, r3, -(3 * 8) 1457 ld_add r0, r3, 8 1458 ld_add r1, r3, 8 1459 ld r2, r3 1460hand_unalign_slow_nonuser: 1461 mfspr r3, SPR_SYSTEM_SAVE_K_1 1462 __int_hand INT_UNALIGN_DATA, UNALIGN_DATA_SLOW, int_unalign 1463 1464/* The unaligned data support needs to read all the registers. */ 1465int_unalign: 1466 push_extra_callee_saves r0 1467 j do_unaligned 1468ENDPROC(hand_unalign_slow) 1469 1470/* Fill the return address stack with nonzero entries. */ 1471STD_ENTRY(fill_ra_stack) 1472 { 1473 move r0, lr 1474 jal 1f 1475 } 14761: jal 2f 14772: jal 3f 14783: jal 4f 14794: jrp r0 1480 STD_ENDPROC(fill_ra_stack) 1481 1482 .macro int_hand vecnum, vecname, c_routine, processing=handle_interrupt 1483 .org (\vecnum << 8) 1484 __int_hand \vecnum, \vecname, \c_routine, \processing 1485 .endm 1486 1487/* Include .intrpt array of interrupt vectors */ 1488 .section ".intrpt", "ax" 1489 .global intrpt_start 1490intrpt_start: 1491 1492#ifndef CONFIG_USE_PMC 1493#define handle_perf_interrupt bad_intr 1494#endif 1495 1496#ifndef CONFIG_HARDWALL 1497#define do_hardwall_trap bad_intr 1498#endif 1499 1500 int_hand INT_MEM_ERROR, MEM_ERROR, do_trap 1501 int_hand INT_SINGLE_STEP_3, SINGLE_STEP_3, bad_intr 1502#if CONFIG_KERNEL_PL == 2 1503 int_hand INT_SINGLE_STEP_2, SINGLE_STEP_2, gx_singlestep_handle 1504 int_hand INT_SINGLE_STEP_1, SINGLE_STEP_1, bad_intr 1505#else 1506 int_hand INT_SINGLE_STEP_2, SINGLE_STEP_2, bad_intr 1507 int_hand INT_SINGLE_STEP_1, SINGLE_STEP_1, gx_singlestep_handle 1508#endif 1509 int_hand INT_SINGLE_STEP_0, SINGLE_STEP_0, bad_intr 1510 int_hand INT_IDN_COMPLETE, IDN_COMPLETE, bad_intr 1511 int_hand INT_UDN_COMPLETE, UDN_COMPLETE, bad_intr 1512 int_hand INT_ITLB_MISS, ITLB_MISS, do_page_fault 1513 int_hand INT_ILL, ILL, do_trap 1514 int_hand INT_GPV, GPV, do_trap 1515 int_hand INT_IDN_ACCESS, IDN_ACCESS, do_trap 1516 int_hand INT_UDN_ACCESS, UDN_ACCESS, do_trap 1517 int_hand INT_SWINT_3, SWINT_3, do_trap 1518 int_hand INT_SWINT_2, SWINT_2, do_trap 1519 int_hand INT_SWINT_1, SWINT_1, SYSCALL, handle_syscall 1520 int_hand INT_SWINT_0, SWINT_0, do_trap 1521 int_hand INT_ILL_TRANS, ILL_TRANS, do_trap 1522 int_hand_unalign_fast INT_UNALIGN_DATA, UNALIGN_DATA 1523 int_hand INT_DTLB_MISS, DTLB_MISS, do_page_fault 1524 int_hand INT_DTLB_ACCESS, DTLB_ACCESS, do_page_fault 1525 int_hand INT_IDN_FIREWALL, IDN_FIREWALL, do_hardwall_trap 1526 int_hand INT_UDN_FIREWALL, UDN_FIREWALL, do_hardwall_trap 1527 int_hand INT_TILE_TIMER, TILE_TIMER, do_timer_interrupt 1528 int_hand INT_IDN_TIMER, IDN_TIMER, bad_intr 1529 int_hand INT_UDN_TIMER, UDN_TIMER, bad_intr 1530 int_hand INT_IDN_AVAIL, IDN_AVAIL, bad_intr 1531 int_hand INT_UDN_AVAIL, UDN_AVAIL, bad_intr 1532 int_hand INT_IPI_3, IPI_3, bad_intr 1533#if CONFIG_KERNEL_PL == 2 1534 int_hand INT_IPI_2, IPI_2, tile_dev_intr 1535 int_hand INT_IPI_1, IPI_1, bad_intr 1536#else 1537 int_hand INT_IPI_2, IPI_2, bad_intr 1538 int_hand INT_IPI_1, IPI_1, tile_dev_intr 1539#endif 1540 int_hand INT_IPI_0, IPI_0, bad_intr 1541 int_hand INT_PERF_COUNT, PERF_COUNT, \ 1542 handle_perf_interrupt, handle_nmi 1543 int_hand INT_AUX_PERF_COUNT, AUX_PERF_COUNT, \ 1544 handle_perf_interrupt, handle_nmi 1545 int_hand INT_INTCTRL_3, INTCTRL_3, bad_intr 1546#if CONFIG_KERNEL_PL == 2 1547 dc_dispatch INT_INTCTRL_2, INTCTRL_2 1548 int_hand INT_INTCTRL_1, INTCTRL_1, bad_intr 1549#else 1550 int_hand INT_INTCTRL_2, INTCTRL_2, bad_intr 1551 dc_dispatch INT_INTCTRL_1, INTCTRL_1 1552#endif 1553 int_hand INT_INTCTRL_0, INTCTRL_0, bad_intr 1554 int_hand INT_MESSAGE_RCV_DWNCL, MESSAGE_RCV_DWNCL, \ 1555 hv_message_intr 1556 int_hand INT_DEV_INTR_DWNCL, DEV_INTR_DWNCL, bad_intr 1557 int_hand INT_I_ASID, I_ASID, bad_intr 1558 int_hand INT_D_ASID, D_ASID, bad_intr 1559 int_hand INT_DOUBLE_FAULT, DOUBLE_FAULT, do_trap 1560 1561 /* Synthetic interrupt delivered only by the simulator */ 1562 int_hand INT_BREAKPOINT, BREAKPOINT, do_breakpoint 1563 /* Synthetic interrupt delivered by hv */ 1564 int_hand INT_NMI_DWNCL, NMI_DWNCL, do_nmi, handle_nmi 1565