1/*
   2 * Copyright 2010 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/init.h>
  20#include <linux/unistd.h>
  21#include <asm/ptrace.h>
  22#include <asm/thread_info.h>
  23#include <asm/irqflags.h>
  24#include <asm/atomic_32.h>
  25#include <asm/asm-offsets.h>
  26#include <hv/hypervisor.h>
  27#include <arch/abi.h>
  28#include <arch/interrupts.h>
  29#include <arch/spr_def.h>
  30
  31#ifdef CONFIG_PREEMPT
  32# error "No support for kernel preemption currently"
  33#endif
  34
  35#define PTREGS_PTR(reg, ptreg) addli reg, sp, C_ABI_SAVE_AREA_SIZE + (ptreg)
  36
  37#define PTREGS_OFFSET_SYSCALL PTREGS_OFFSET_REG(TREG_SYSCALL_NR)
  38
  39#if !CHIP_HAS_WH64()
  40	/* By making this an empty macro, we can use wh64 in the code. */
  41	.macro  wh64 reg
  42	.endm
  43#endif
  44
  45	.macro  push_reg reg, ptr=sp, delta=-4
  46	{
  47	 sw     \ptr, \reg
  48	 addli  \ptr, \ptr, \delta
  49	}
  50	.endm
  51
  52	.macro  pop_reg reg, ptr=sp, delta=4
  53	{
  54	 lw     \reg, \ptr
  55	 addli  \ptr, \ptr, \delta
  56	}
  57	.endm
  58
  59	.macro  pop_reg_zero reg, zreg, ptr=sp, delta=4
  60	{
  61	 move   \zreg, zero
  62	 lw     \reg, \ptr
  63	 addi   \ptr, \ptr, \delta
  64	}
  65	.endm
  66
  67	.macro  push_extra_callee_saves reg
  68	PTREGS_PTR(\reg, PTREGS_OFFSET_REG(51))
  69	push_reg r51, \reg
  70	push_reg r50, \reg
  71	push_reg r49, \reg
  72	push_reg r48, \reg
  73	push_reg r47, \reg
  74	push_reg r46, \reg
  75	push_reg r45, \reg
  76	push_reg r44, \reg
  77	push_reg r43, \reg
  78	push_reg r42, \reg
  79	push_reg r41, \reg
  80	push_reg r40, \reg
  81	push_reg r39, \reg
  82	push_reg r38, \reg
  83	push_reg r37, \reg
  84	push_reg r36, \reg
  85	push_reg r35, \reg
  86	push_reg r34, \reg, PTREGS_OFFSET_BASE - PTREGS_OFFSET_REG(34)
  87	.endm
  88
  89	.macro  panic str
  90	.pushsection .rodata, "a"
  911:
  92	.asciz  "\str"
  93	.popsection
  94	{
  95	 moveli r0, lo16(1b)
  96	}
  97	{
  98	 auli   r0, r0, ha16(1b)
  99	 jal    panic
 100	}
 101	.endm
 102
 103#ifdef __COLLECT_LINKER_FEEDBACK__
 104	.pushsection .text.intvec_feedback,"ax"
 105intvec_feedback:
 106	.popsection
 107#endif
 108
 109	/*
 110	 * Default interrupt handler.
 111	 *
 112	 * vecnum is where we'll put this code.
 113	 * c_routine is the C routine we'll call.
 114	 *
 115	 * The C routine is passed two arguments:
 116	 * - A pointer to the pt_regs state.
 117	 * - The interrupt vector number.
 118	 *
 119	 * The "processing" argument specifies the code for processing
 120	 * the interrupt. Defaults to "handle_interrupt".
 121	 */
 122	.macro  int_hand vecnum, vecname, c_routine, processing=handle_interrupt
 123	.org    (\vecnum << 8)
 124intvec_\vecname:
 125	.ifc    \vecnum, INT_SWINT_1
 126	blz     TREG_SYSCALL_NR_NAME, sys_cmpxchg
 127	.endif
 128
 129	/* Temporarily save a register so we have somewhere to work. */
 130
 131	mtspr   SPR_SYSTEM_SAVE_K_1, r0
 132	mfspr   r0, SPR_EX_CONTEXT_K_1
 133
 134	/* The cmpxchg code clears sp to force us to reset it here on fault. */
 135	{
 136	 bz     sp, 2f
 137	 andi   r0, r0, SPR_EX_CONTEXT_1_1__PL_MASK  /* mask off ICS */
 138	}
 139
 140	.ifc    \vecnum, INT_DOUBLE_FAULT
 141	/*
 142	 * For double-faults from user-space, fall through to the normal
 143	 * register save and stack setup path.  Otherwise, it's the
 144	 * hypervisor giving us one last chance to dump diagnostics, and we
 145	 * branch to the kernel_double_fault routine to do so.
 146	 */
 147	bz      r0, 1f
 148	j       _kernel_double_fault
 1491:
 150	.else
 151	/*
 152	 * If we're coming from user-space, then set sp to the top of
 153	 * the kernel stack.  Otherwise, assume sp is already valid.
 154	 */
 155	{
 156	 bnz    r0, 0f
 157	 move   r0, sp
 158	}
 159	.endif
 160
 161	.ifc    \c_routine, do_page_fault
 162	/*
 163	 * The page_fault handler may be downcalled directly by the
 164	 * hypervisor even when Linux is running and has ICS set.
 165	 *
 166	 * In this case the contents of EX_CONTEXT_K_1 reflect the
 167	 * previous fault and can't be relied on to choose whether or
 168	 * not to reinitialize the stack pointer.  So we add a test
 169	 * to see whether SYSTEM_SAVE_K_2 has the high bit set,
 170	 * and if so we don't reinitialize sp, since we must be coming
 171	 * from Linux.  (In fact the precise case is !(val & ~1),
 172	 * but any Linux PC has to have the high bit set.)
 173	 *
 174	 * Note that the hypervisor *always* sets SYSTEM_SAVE_K_2 for
 175	 * any path that turns into a downcall to one of our TLB handlers.
 176	 */
 177	mfspr   r0, SPR_SYSTEM_SAVE_K_2
 178	{
 179	 blz    r0, 0f    /* high bit in S_S_1_2 is for a PC to use */
 180	 move   r0, sp
 181	}
 182	.endif
 183
 1842:
 185	/*
 186	 * SYSTEM_SAVE_K_0 holds the cpu number in the low bits, and
 187	 * the current stack top in the higher bits.  So we recover
 188	 * our stack top by just masking off the low bits, then
 189	 * point sp at the top aligned address on the actual stack page.
 190	 */
 191	mfspr   r0, SPR_SYSTEM_SAVE_K_0
 192	mm      r0, r0, zero, LOG2_THREAD_SIZE, 31
 193
 1940:
 195	/*
 196	 * Align the stack mod 64 so we can properly predict what
 197	 * cache lines we need to write-hint to reduce memory fetch
 198	 * latency as we enter the kernel.  The layout of memory is
 199	 * as follows, with cache line 0 at the lowest VA, and cache
 200	 * line 4 just below the r0 value this "andi" computes.
 201	 * Note that we never write to cache line 4, and we skip
 202	 * cache line 1 for syscalls.
 203	 *
 204	 *    cache line 4: ptregs padding (two words)
 205	 *    cache line 3: r46...lr, pc, ex1, faultnum, orig_r0, flags, pad
 206	 *    cache line 2: r30...r45
 207	 *    cache line 1: r14...r29
 208	 *    cache line 0: 2 x frame, r0..r13
 209	 */
 
 
 
 210	andi    r0, r0, -64
 211
 212	/*
 213	 * Push the first four registers on the stack, so that we can set
 214	 * them to vector-unique values before we jump to the common code.
 215	 *
 216	 * Registers are pushed on the stack as a struct pt_regs,
 217	 * with the sp initially just above the struct, and when we're
 218	 * done, sp points to the base of the struct, minus
 219	 * C_ABI_SAVE_AREA_SIZE, so we can directly jal to C code.
 220	 *
 221	 * This routine saves just the first four registers, plus the
 222	 * stack context so we can do proper backtracing right away,
 223	 * and defers to handle_interrupt to save the rest.
 224	 * The backtracer needs pc, ex1, lr, sp, r52, and faultnum.
 225	 */
 226	addli   r0, r0, PTREGS_OFFSET_LR - (PTREGS_SIZE + KSTK_PTREGS_GAP)
 227	wh64    r0    /* cache line 3 */
 228	{
 229	 sw     r0, lr
 230	 addli  r0, r0, PTREGS_OFFSET_SP - PTREGS_OFFSET_LR
 231	}
 232	{
 233	 sw     r0, sp
 234	 addli  sp, r0, PTREGS_OFFSET_REG(52) - PTREGS_OFFSET_SP
 235	}
 236	{
 237	 sw     sp, r52
 238	 addli  sp, sp, PTREGS_OFFSET_REG(1) - PTREGS_OFFSET_REG(52)
 239	}
 240	wh64    sp    /* cache line 0 */
 241	{
 242	 sw     sp, r1
 243	 addli  sp, sp, PTREGS_OFFSET_REG(2) - PTREGS_OFFSET_REG(1)
 244	}
 245	{
 246	 sw     sp, r2
 247	 addli  sp, sp, PTREGS_OFFSET_REG(3) - PTREGS_OFFSET_REG(2)
 248	}
 249	{
 250	 sw     sp, r3
 251	 addli  sp, sp, PTREGS_OFFSET_PC - PTREGS_OFFSET_REG(3)
 252	}
 253	mfspr   r0, SPR_EX_CONTEXT_K_0
 254	.ifc \processing,handle_syscall
 255	/*
 256	 * Bump the saved PC by one bundle so that when we return, we won't
 257	 * execute the same swint instruction again.  We need to do this while
 258	 * we're in the critical section.
 259	 */
 260	addi    r0, r0, 8
 261	.endif
 262	{
 263	 sw     sp, r0
 264	 addli  sp, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_PC
 265	}
 266	mfspr   r0, SPR_EX_CONTEXT_K_1
 267	{
 268	 sw     sp, r0
 269	 addi   sp, sp, PTREGS_OFFSET_FAULTNUM - PTREGS_OFFSET_EX1
 270	/*
 271	 * Use r0 for syscalls so it's a temporary; use r1 for interrupts
 272	 * so that it gets passed through unchanged to the handler routine.
 273	 * Note that the .if conditional confusingly spans bundles.
 274	 */
 275	 .ifc \processing,handle_syscall
 276	 movei  r0, \vecnum
 277	}
 278	{
 279	 sw     sp, r0
 280	 .else
 281	 movei  r1, \vecnum
 282	}
 283	{
 284	 sw     sp, r1
 285	 .endif
 286	 addli  sp, sp, PTREGS_OFFSET_REG(0) - PTREGS_OFFSET_FAULTNUM
 287	}
 288	mfspr   r0, SPR_SYSTEM_SAVE_K_1    /* Original r0 */
 289	{
 290	 sw     sp, r0
 291	 addi   sp, sp, -PTREGS_OFFSET_REG(0) - 4
 292	}
 293	{
 294	 sw     sp, zero        /* write zero into "Next SP" frame pointer */
 295	 addi   sp, sp, -4      /* leave SP pointing at bottom of frame */
 296	}
 297	.ifc \processing,handle_syscall
 298	j       handle_syscall
 299	.else
 300	/*
 301	 * Capture per-interrupt SPR context to registers.
 302	 * We overload the meaning of r3 on this path such that if its bit 31
 303	 * is set, we have to mask all interrupts including NMIs before
 304	 * clearing the interrupt critical section bit.
 305	 * See discussion below at "finish_interrupt_save".
 306	 */
 307	.ifc \c_routine, do_page_fault
 308	mfspr   r2, SPR_SYSTEM_SAVE_K_3   /* address of page fault */
 309	mfspr   r3, SPR_SYSTEM_SAVE_K_2   /* info about page fault */
 310	.else
 311	.ifc \vecnum, INT_DOUBLE_FAULT
 312	{
 313	 mfspr  r2, SPR_SYSTEM_SAVE_K_2   /* double fault info from HV */
 314	 movei  r3, 0
 315	}
 316	.else
 317	.ifc \c_routine, do_trap
 318	{
 319	 mfspr  r2, GPV_REASON
 320	 movei  r3, 0
 321	}
 322	.else
 323	.ifc \c_routine, op_handle_perf_interrupt
 324	{
 325	 mfspr  r2, PERF_COUNT_STS
 326	 movei  r3, -1   /* not used, but set for consistency */
 327	}
 328	.else
 329#if CHIP_HAS_AUX_PERF_COUNTERS()
 330	.ifc \c_routine, op_handle_aux_perf_interrupt
 331	{
 332	 mfspr  r2, AUX_PERF_COUNT_STS
 333	 movei  r3, -1   /* not used, but set for consistency */
 334	}
 335	.else
 336#endif
 337	movei   r3, 0
 338#if CHIP_HAS_AUX_PERF_COUNTERS()
 339	.endif
 340#endif
 341	.endif
 342	.endif
 343	.endif
 344	.endif
 345	/* Put function pointer in r0 */
 346	moveli  r0, lo16(\c_routine)
 347	{
 348	 auli   r0, r0, ha16(\c_routine)
 349	 j       \processing
 350	}
 351	.endif
 352	ENDPROC(intvec_\vecname)
 353
 354#ifdef __COLLECT_LINKER_FEEDBACK__
 355	.pushsection .text.intvec_feedback,"ax"
 356	.org    (\vecnum << 5)
 357	FEEDBACK_ENTER_EXPLICIT(intvec_\vecname, .intrpt1, 1 << 8)
 358	jrp     lr
 359	.popsection
 360#endif
 361
 362	.endm
 363
 364
 365	/*
 366	 * Save the rest of the registers that we didn't save in the actual
 367	 * vector itself.  We can't use r0-r10 inclusive here.
 368	 */
 369	.macro  finish_interrupt_save, function
 370
 371	/* If it's a syscall, save a proper orig_r0, otherwise just zero. */
 372	PTREGS_PTR(r52, PTREGS_OFFSET_ORIG_R0)
 373	{
 374	 .ifc \function,handle_syscall
 375	 sw     r52, r0
 376	 .else
 377	 sw     r52, zero
 378	 .endif
 379	 PTREGS_PTR(r52, PTREGS_OFFSET_TP)
 380	}
 381
 382	/*
 383	 * For ordinary syscalls, we save neither caller- nor callee-
 384	 * save registers, since the syscall invoker doesn't expect the
 385	 * caller-saves to be saved, and the called kernel functions will
 386	 * take care of saving the callee-saves for us.
 387	 *
 388	 * For interrupts we save just the caller-save registers.  Saving
 389	 * them is required (since the "caller" can't save them).  Again,
 390	 * the called kernel functions will restore the callee-save
 391	 * registers for us appropriately.
 392	 *
 393	 * On return, we normally restore nothing special for syscalls,
 394	 * and just the caller-save registers for interrupts.
 395	 *
 396	 * However, there are some important caveats to all this:
 397	 *
 398	 * - We always save a few callee-save registers to give us
 399	 *   some scratchpad registers to carry across function calls.
 400	 *
 401	 * - fork/vfork/etc require us to save all the callee-save
 402	 *   registers, which we do in PTREGS_SYSCALL_ALL_REGS, below.
 403	 *
 404	 * - We always save r0..r5 and r10 for syscalls, since we need
 405	 *   to reload them a bit later for the actual kernel call, and
 406	 *   since we might need them for -ERESTARTNOINTR, etc.
 407	 *
 408	 * - Before invoking a signal handler, we save the unsaved
 409	 *   callee-save registers so they are visible to the
 410	 *   signal handler or any ptracer.
 411	 *
 412	 * - If the unsaved callee-save registers are modified, we set
 413	 *   a bit in pt_regs so we know to reload them from pt_regs
 414	 *   and not just rely on the kernel function unwinding.
 415	 *   (Done for ptrace register writes and SA_SIGINFO handler.)
 416	 */
 417	{
 418	 sw     r52, tp
 419	 PTREGS_PTR(r52, PTREGS_OFFSET_REG(33))
 420	}
 421	wh64    r52    /* cache line 2 */
 422	push_reg r33, r52
 423	push_reg r32, r52
 424	push_reg r31, r52
 425	.ifc \function,handle_syscall
 426	push_reg r30, r52, PTREGS_OFFSET_SYSCALL - PTREGS_OFFSET_REG(30)
 427	push_reg TREG_SYSCALL_NR_NAME, r52, \
 428	  PTREGS_OFFSET_REG(5) - PTREGS_OFFSET_SYSCALL
 429	.else
 430
 431	push_reg r30, r52, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(30)
 432	wh64    r52    /* cache line 1 */
 433	push_reg r29, r52
 434	push_reg r28, r52
 435	push_reg r27, r52
 436	push_reg r26, r52
 437	push_reg r25, r52
 438	push_reg r24, r52
 439	push_reg r23, r52
 440	push_reg r22, r52
 441	push_reg r21, r52
 442	push_reg r20, r52
 443	push_reg r19, r52
 444	push_reg r18, r52
 445	push_reg r17, r52
 446	push_reg r16, r52
 447	push_reg r15, r52
 448	push_reg r14, r52
 449	push_reg r13, r52
 450	push_reg r12, r52
 451	push_reg r11, r52
 452	push_reg r10, r52
 453	push_reg r9, r52
 454	push_reg r8, r52
 455	push_reg r7, r52
 456	push_reg r6, r52
 457
 458	.endif
 459
 460	push_reg r5, r52
 461	sw      r52, r4
 462
 463	/* Load tp with our per-cpu offset. */
 464#ifdef CONFIG_SMP
 465	{
 466	 mfspr  r20, SPR_SYSTEM_SAVE_K_0
 467	 moveli r21, lo16(__per_cpu_offset)
 468	}
 469	{
 470	 auli   r21, r21, ha16(__per_cpu_offset)
 471	 mm     r20, r20, zero, 0, LOG2_THREAD_SIZE-1
 472	}
 473	s2a     r20, r20, r21
 474	lw      tp, r20
 475#else
 476	move    tp, zero
 477#endif
 478
 479	/*
 480	 * If we will be returning to the kernel, we will need to
 481	 * reset the interrupt masks to the state they had before.
 482	 * Set DISABLE_IRQ in flags iff we came from PL1 with irqs disabled.
 483	 * We load flags in r32 here so we can jump to .Lrestore_regs
 484	 * directly after do_page_fault_ics() if necessary.
 485	 */
 486	mfspr   r32, SPR_EX_CONTEXT_K_1
 487	{
 488	 andi   r32, r32, SPR_EX_CONTEXT_1_1__PL_MASK  /* mask off ICS */
 489	 PTREGS_PTR(r21, PTREGS_OFFSET_FLAGS)
 490	}
 491	bzt     r32, 1f       /* zero if from user space */
 492	IRQS_DISABLED(r32)    /* zero if irqs enabled */
 493#if PT_FLAGS_DISABLE_IRQ != 1
 494# error Value of IRQS_DISABLED used to set PT_FLAGS_DISABLE_IRQ; fix
 495#endif
 4961:
 497	.ifnc \function,handle_syscall
 498	/* Record the fact that we saved the caller-save registers above. */
 499	ori     r32, r32, PT_FLAGS_CALLER_SAVES
 500	.endif
 501	sw      r21, r32
 502
 503#ifdef __COLLECT_LINKER_FEEDBACK__
 504	/*
 505	 * Notify the feedback routines that we were in the
 506	 * appropriate fixed interrupt vector area.  Note that we
 507	 * still have ICS set at this point, so we can't invoke any
 508	 * atomic operations or we will panic.  The feedback
 509	 * routines internally preserve r0..r10 and r30 up.
 510	 */
 511	.ifnc \function,handle_syscall
 512	shli    r20, r1, 5
 513	.else
 514	moveli  r20, INT_SWINT_1 << 5
 515	.endif
 516	addli   r20, r20, lo16(intvec_feedback)
 517	auli    r20, r20, ha16(intvec_feedback)
 518	jalr    r20
 519
 520	/* And now notify the feedback routines that we are here. */
 521	FEEDBACK_ENTER(\function)
 522#endif
 523
 524	/*
 525	 * we've captured enough state to the stack (including in
 526	 * particular our EX_CONTEXT state) that we can now release
 527	 * the interrupt critical section and replace it with our
 528	 * standard "interrupts disabled" mask value.  This allows
 529	 * synchronous interrupts (and profile interrupts) to punch
 530	 * through from this point onwards.
 531	 *
 532	 * If bit 31 of r3 is set during a non-NMI interrupt, we know we
 533	 * are on the path where the hypervisor has punched through our
 534	 * ICS with a page fault, so we call out to do_page_fault_ics()
 535	 * to figure out what to do with it.  If the fault was in
 536	 * an atomic op, we unlock the atomic lock, adjust the
 537	 * saved register state a little, and return "zero" in r4,
 538	 * falling through into the normal page-fault interrupt code.
 539	 * If the fault was in a kernel-space atomic operation, then
 540	 * do_page_fault_ics() resolves it itself, returns "one" in r4,
 541	 * and as a result goes directly to restoring registers and iret,
 542	 * without trying to adjust the interrupt masks at all.
 543	 * The do_page_fault_ics() API involves passing and returning
 544	 * a five-word struct (in registers) to avoid writing the
 545	 * save and restore code here.
 546	 */
 547	.ifc \function,handle_nmi
 548	IRQ_DISABLE_ALL(r20)
 549	.else
 550	.ifnc \function,handle_syscall
 551	bgezt   r3, 1f
 552	{
 553	 PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
 554	 jal    do_page_fault_ics
 555	}
 556	FEEDBACK_REENTER(\function)
 557	bzt     r4, 1f
 558	j       .Lrestore_regs
 5591:
 560	.endif
 561	IRQ_DISABLE(r20, r21)
 562	.endif
 563	mtspr   INTERRUPT_CRITICAL_SECTION, zero
 564
 565#if CHIP_HAS_WH64()
 566	/*
 567	 * Prepare the first 256 stack bytes to be rapidly accessible
 568	 * without having to fetch the background data.  We don't really
 569	 * know how far to write-hint, but kernel stacks generally
 570	 * aren't that big, and write-hinting here does take some time.
 571	 */
 572	addi    r52, sp, -64
 573	{
 574	 wh64   r52
 575	 addi   r52, r52, -64
 576	}
 577	{
 578	 wh64   r52
 579	 addi   r52, r52, -64
 580	}
 581	{
 582	 wh64   r52
 583	 addi   r52, r52, -64
 584	}
 585	wh64    r52
 586#endif
 587
 588#ifdef CONFIG_TRACE_IRQFLAGS
 589	.ifnc \function,handle_nmi
 590	/*
 591	 * We finally have enough state set up to notify the irq
 592	 * tracing code that irqs were disabled on entry to the handler.
 593	 * The TRACE_IRQS_OFF call clobbers registers r0-r29.
 594	 * For syscalls, we already have the register state saved away
 595	 * on the stack, so we don't bother to do any register saves here,
 596	 * and later we pop the registers back off the kernel stack.
 597	 * For interrupt handlers, save r0-r3 in callee-saved registers.
 598	 */
 599	.ifnc \function,handle_syscall
 600	{ move r30, r0; move r31, r1 }
 601	{ move r32, r2; move r33, r3 }
 602	.endif
 603	TRACE_IRQS_OFF
 604	.ifnc \function,handle_syscall
 605	{ move r0, r30; move r1, r31 }
 606	{ move r2, r32; move r3, r33 }
 607	.endif
 608	.endif
 609#endif
 610
 611	.endm
 612
 613	.macro  check_single_stepping, kind, not_single_stepping
 614	/*
 615	 * Check for single stepping in user-level priv
 616	 *   kind can be "normal", "ill", or "syscall"
 617	 * At end, if fall-thru
 618	 *   r29: thread_info->step_state
 619	 *   r28: &pt_regs->pc
 620	 *   r27: pt_regs->pc
 621	 *   r26: thread_info->step_state->buffer
 622	 */
 623
 624	/* Check for single stepping */
 625	GET_THREAD_INFO(r29)
 626	{
 627	 /* Get pointer to field holding step state */
 628	 addi   r29, r29, THREAD_INFO_STEP_STATE_OFFSET
 629
 630	 /* Get pointer to EX1 in register state */
 631	 PTREGS_PTR(r27, PTREGS_OFFSET_EX1)
 632	}
 633	{
 634	 /* Get pointer to field holding PC */
 635	 PTREGS_PTR(r28, PTREGS_OFFSET_PC)
 636
 637	 /* Load the pointer to the step state */
 638	 lw     r29, r29
 639	}
 640	/* Load EX1 */
 641	lw      r27, r27
 642	{
 643	 /* Points to flags */
 644	 addi   r23, r29, SINGLESTEP_STATE_FLAGS_OFFSET
 645
 646	 /* No single stepping if there is no step state structure */
 647	 bzt    r29, \not_single_stepping
 648	}
 649	{
 650	 /* mask off ICS and any other high bits */
 651	 andi   r27, r27, SPR_EX_CONTEXT_1_1__PL_MASK
 652
 653	 /* Load pointer to single step instruction buffer */
 654	 lw     r26, r29
 655	}
 656	/* Check priv state */
 657	bnz     r27, \not_single_stepping
 658
 659	/* Get flags */
 660	lw      r22, r23
 661	{
 662	 /* Branch if single-step mode not enabled */
 663	 bbnst  r22, \not_single_stepping
 664
 665	 /* Clear enabled flag */
 666	 andi   r22, r22, ~SINGLESTEP_STATE_MASK_IS_ENABLED
 667	}
 668	.ifc \kind,normal
 669	{
 670	 /* Load PC */
 671	 lw     r27, r28
 672
 673	 /* Point to the entry containing the original PC */
 674	 addi   r24, r29, SINGLESTEP_STATE_ORIG_PC_OFFSET
 675	}
 676	{
 677	 /* Disable single stepping flag */
 678	 sw     r23, r22
 679	}
 680	{
 681	 /* Get the original pc */
 682	 lw     r24, r24
 683
 684	 /* See if the PC is at the start of the single step buffer */
 685	 seq    r25, r26, r27
 686	}
 687	/*
 688	 * NOTE: it is really expected that the PC be in the single step buffer
 689	 *       at this point
 690	 */
 691	bzt     r25, \not_single_stepping
 692
 693	/* Restore the original PC */
 694	sw      r28, r24
 695	.else
 696	.ifc \kind,syscall
 697	{
 698	 /* Load PC */
 699	 lw     r27, r28
 700
 701	 /* Point to the entry containing the next PC */
 702	 addi   r24, r29, SINGLESTEP_STATE_NEXT_PC_OFFSET
 703	}
 704	{
 705	 /* Increment the stopped PC by the bundle size */
 706	 addi   r26, r26, 8
 707
 708	 /* Disable single stepping flag */
 709	 sw     r23, r22
 710	}
 711	{
 712	 /* Get the next pc */
 713	 lw     r24, r24
 714
 715	 /*
 716	  * See if the PC is one bundle past the start of the
 717	  * single step buffer
 718	  */
 719	 seq    r25, r26, r27
 720	}
 721	{
 722	 /*
 723	  * NOTE: it is really expected that the PC be in the
 724	  * single step buffer at this point
 725	  */
 726	 bzt    r25, \not_single_stepping
 727	}
 728	/* Set to the next PC */
 729	sw      r28, r24
 730	.else
 731	{
 732	 /* Point to 3rd bundle in buffer */
 733	 addi   r25, r26, 16
 734
 735	 /* Load PC */
 736	 lw      r27, r28
 737	}
 738	{
 739	 /* Disable single stepping flag */
 740	 sw      r23, r22
 741
 742	 /* See if the PC is in the single step buffer */
 743	 slte_u  r24, r26, r27
 744	}
 745	{
 746	 slte_u r25, r27, r25
 747
 748	 /*
 749	  * NOTE: it is really expected that the PC be in the
 750	  * single step buffer at this point
 751	  */
 752	 bzt    r24, \not_single_stepping
 753	}
 754	bzt     r25, \not_single_stepping
 755	.endif
 756	.endif
 757	.endm
 758
 759	/*
 760	 * Redispatch a downcall.
 761	 */
 762	.macro  dc_dispatch vecnum, vecname
 763	.org    (\vecnum << 8)
 764intvec_\vecname:
 765	j       hv_downcall_dispatch
 766	ENDPROC(intvec_\vecname)
 767	.endm
 768
 769	/*
 770	 * Common code for most interrupts.  The C function we're eventually
 771	 * going to is in r0, and the faultnum is in r1; the original
 772	 * values for those registers are on the stack.
 773	 */
 774	.pushsection .text.handle_interrupt,"ax"
 775handle_interrupt:
 776	finish_interrupt_save handle_interrupt
 777
 778	/*
 779	 * Check for if we are single stepping in user level. If so, then
 780	 * we need to restore the PC.
 781	 */
 782
 783	check_single_stepping normal, .Ldispatch_interrupt
 784.Ldispatch_interrupt:
 785
 786	/* Jump to the C routine; it should enable irqs as soon as possible. */
 787	{
 788	 jalr   r0
 789	 PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
 790	}
 791	FEEDBACK_REENTER(handle_interrupt)
 792	{
 793	 movei  r30, 0   /* not an NMI */
 794	 j      interrupt_return
 795	}
 796	STD_ENDPROC(handle_interrupt)
 797
 798/*
 799 * This routine takes a boolean in r30 indicating if this is an NMI.
 800 * If so, we also expect a boolean in r31 indicating whether to
 801 * re-enable the oprofile interrupts.
 
 
 
 
 802 */
 803STD_ENTRY(interrupt_return)
 804	/* If we're resuming to kernel space, don't check thread flags. */
 805	{
 806	 bnz    r30, .Lrestore_all  /* NMIs don't special-case user-space */
 807	 PTREGS_PTR(r29, PTREGS_OFFSET_EX1)
 808	}
 809	lw      r29, r29
 810	andi    r29, r29, SPR_EX_CONTEXT_1_1__PL_MASK  /* mask off ICS */
 
 
 
 
 
 
 811	{
 812	 bzt    r29, .Lresume_userspace
 813	 PTREGS_PTR(r29, PTREGS_OFFSET_PC)
 814	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 815
 816	/* If we're resuming to _cpu_idle_nap, bump PC forward by 8. */
 817	{
 818	 lw     r28, r29
 819	 moveli r27, lo16(_cpu_idle_nap)
 820	}
 821	{
 
 822	 auli   r27, r27, ha16(_cpu_idle_nap)
 823	}
 824	{
 825	 seq    r27, r27, r28
 826	}
 827	{
 828	 bbns   r27, .Lrestore_all
 829	 addi   r28, r28, 8
 830	}
 831	sw      r29, r28
 832	j       .Lrestore_all
 833
 834.Lresume_userspace:
 835	FEEDBACK_REENTER(interrupt_return)
 836
 837	/*
 
 
 
 
 
 
 
 
 
 
 
 
 838	 * Disable interrupts so as to make sure we don't
 839	 * miss an interrupt that sets any of the thread flags (like
 840	 * need_resched or sigpending) between sampling and the iret.
 841	 * Routines like schedule() or do_signal() may re-enable
 842	 * interrupts before returning.
 843	 */
 844	IRQ_DISABLE(r20, r21)
 845	TRACE_IRQS_OFF  /* Note: clobbers registers r0-r29 */
 846
 847	/* Get base of stack in r32; note r30/31 are used as arguments here. */
 848	GET_THREAD_INFO(r32)
 849
 850
 851	/* Check to see if there is any work to do before returning to user. */
 852	{
 853	 addi   r29, r32, THREAD_INFO_FLAGS_OFFSET
 854	 moveli r1, lo16(_TIF_ALLWORK_MASK)
 855	}
 856	{
 857	 lw     r29, r29
 858	 auli   r1, r1, ha16(_TIF_ALLWORK_MASK)
 859	}
 860	and     r1, r29, r1
 861	bzt     r1, .Lrestore_all
 862
 863	/*
 864	 * Make sure we have all the registers saved for signal
 865	 * handling or single-step.  Call out to C code to figure out
 866	 * exactly what we need to do for each flag bit, then if
 867	 * necessary, reload the flags and recheck.
 868	 */
 869	push_extra_callee_saves r0
 870	{
 871	 PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
 872	 jal    do_work_pending
 873	}
 874	bnz     r0, .Lresume_userspace
 
 
 
 875
 876	/*
 877	 * In the NMI case we
 878	 * omit the call to single_process_check_nohz, which normally checks
 879	 * to see if we should start or stop the scheduler tick, because
 880	 * we can't call arbitrary Linux code from an NMI context.
 881	 * We always call the homecache TLB deferral code to re-trigger
 882	 * the deferral mechanism.
 883	 *
 884	 * The other chunk of responsibility this code has is to reset the
 885	 * interrupt masks appropriately to reset irqs and NMIs.  We have
 886	 * to call TRACE_IRQS_OFF and TRACE_IRQS_ON to support all the
 887	 * lockdep-type stuff, but we can't set ICS until afterwards, since
 888	 * ICS can only be used in very tight chunks of code to avoid
 889	 * tripping over various assertions that it is off.
 890	 *
 891	 * (There is what looks like a window of vulnerability here since
 892	 * we might take a profile interrupt between the two SPR writes
 893	 * that set the mask, but since we write the low SPR word first,
 894	 * and our interrupt entry code checks the low SPR word, any
 895	 * profile interrupt will actually disable interrupts in both SPRs
 896	 * before returning, which is OK.)
 897	 */
 898.Lrestore_all:
 899	PTREGS_PTR(r0, PTREGS_OFFSET_EX1)
 900	{
 901	 lw     r0, r0
 902	 PTREGS_PTR(r32, PTREGS_OFFSET_FLAGS)
 903	}
 904	{
 905	 andi   r0, r0, SPR_EX_CONTEXT_1_1__PL_MASK
 906	 lw     r32, r32
 907	}
 908	bnz    r0, 1f
 909	j       2f
 910#if PT_FLAGS_DISABLE_IRQ != 1
 911# error Assuming PT_FLAGS_DISABLE_IRQ == 1 so we can use bbnst below
 912#endif
 9131:	bbnst   r32, 2f
 914	IRQ_DISABLE(r20,r21)
 915	TRACE_IRQS_OFF
 916	movei   r0, 1
 917	mtspr   INTERRUPT_CRITICAL_SECTION, r0
 918	bzt     r30, .Lrestore_regs
 919	j       3f
 9202:	TRACE_IRQS_ON
 921	movei   r0, 1
 922	mtspr   INTERRUPT_CRITICAL_SECTION, r0
 923	IRQ_ENABLE(r20, r21)
 924	bzt     r30, .Lrestore_regs
 9253:
 926
 
 
 
 
 
 
 
 927
 928	/*
 929	 * We now commit to returning from this interrupt, since we will be
 930	 * doing things like setting EX_CONTEXT SPRs and unwinding the stack
 931	 * frame.  No calls should be made to any other code after this point.
 932	 * This code should only be entered with ICS set.
 933	 * r32 must still be set to ptregs.flags.
 934	 * We launch loads to each cache line separately first, so we can
 935	 * get some parallelism out of the memory subsystem.
 936	 * We start zeroing caller-saved registers throughout, since
 937	 * that will save some cycles if this turns out to be a syscall.
 938	 */
 939.Lrestore_regs:
 940	FEEDBACK_REENTER(interrupt_return)   /* called from elsewhere */
 941
 942	/*
 943	 * Rotate so we have one high bit and one low bit to test.
 944	 * - low bit says whether to restore all the callee-saved registers,
 945	 *   or just r30-r33, and r52 up.
 946	 * - high bit (i.e. sign bit) says whether to restore all the
 947	 *   caller-saved registers, or just r0.
 948	 */
 949#if PT_FLAGS_CALLER_SAVES != 2 || PT_FLAGS_RESTORE_REGS != 4
 950# error Rotate trick does not work :-)
 951#endif
 952	{
 953	 rli    r20, r32, 30
 954	 PTREGS_PTR(sp, PTREGS_OFFSET_REG(0))
 955	}
 956
 957	/*
 958	 * Load cache lines 0, 2, and 3 in that order, then use
 959	 * the last loaded value, which makes it likely that the other
 960	 * cache lines have also loaded, at which point we should be
 961	 * able to safely read all the remaining words on those cache
 962	 * lines without waiting for the memory subsystem.
 963	 */
 964	pop_reg_zero r0, r28, sp, PTREGS_OFFSET_REG(30) - PTREGS_OFFSET_REG(0)
 965	pop_reg_zero r30, r2, sp, PTREGS_OFFSET_PC - PTREGS_OFFSET_REG(30)
 966	pop_reg_zero r21, r3, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_PC
 967	pop_reg_zero lr, r4, sp, PTREGS_OFFSET_REG(52) - PTREGS_OFFSET_EX1
 968	{
 969	 mtspr  SPR_EX_CONTEXT_K_0, r21
 970	 move   r5, zero
 971	}
 972	{
 973	 mtspr  SPR_EX_CONTEXT_K_1, lr
 974	 andi   lr, lr, SPR_EX_CONTEXT_1_1__PL_MASK  /* mask off ICS */
 975	}
 976
 977	/* Restore callee-saveds that we actually use. */
 978	pop_reg_zero r52, r6, sp, PTREGS_OFFSET_REG(31) - PTREGS_OFFSET_REG(52)
 979	pop_reg_zero r31, r7
 980	pop_reg_zero r32, r8
 981	pop_reg_zero r33, r9, sp, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(33)
 982
 983	/*
 984	 * If we modified other callee-saveds, restore them now.
 985	 * This is rare, but could be via ptrace or signal handler.
 986	 */
 987	{
 988	 move   r10, zero
 989	 bbs    r20, .Lrestore_callees
 990	}
 991.Lcontinue_restore_regs:
 992
 993	/* Check if we're returning from a syscall. */
 994	{
 995	 move   r11, zero
 996	 blzt   r20, 1f  /* no, so go restore callee-save registers */
 997	}
 998
 999	/*
1000	 * Check if we're returning to userspace.
1001	 * Note that if we're not, we don't worry about zeroing everything.
1002	 */
1003	{
1004	 addli  sp, sp, PTREGS_OFFSET_LR - PTREGS_OFFSET_REG(29)
1005	 bnz    lr, .Lkernel_return
1006	}
1007
1008	/*
1009	 * On return from syscall, we've restored r0 from pt_regs, but we
1010	 * clear the remainder of the caller-saved registers.  We could
1011	 * restore the syscall arguments, but there's not much point,
1012	 * and it ensures user programs aren't trying to use the
1013	 * caller-saves if we clear them, as well as avoiding leaking
1014	 * kernel pointers into userspace.
1015	 */
1016	pop_reg_zero lr, r12, sp, PTREGS_OFFSET_TP - PTREGS_OFFSET_LR
1017	pop_reg_zero tp, r13, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_TP
1018	{
1019	 lw     sp, sp
1020	 move   r14, zero
1021	 move   r15, zero
1022	}
1023	{ move r16, zero; move r17, zero }
1024	{ move r18, zero; move r19, zero }
1025	{ move r20, zero; move r21, zero }
1026	{ move r22, zero; move r23, zero }
1027	{ move r24, zero; move r25, zero }
1028	{ move r26, zero; move r27, zero }
1029
1030	/* Set r1 to errno if we are returning an error, otherwise zero. */
1031	{
1032	 moveli r29, 4096
1033	 sub    r1, zero, r0
1034	}
1035	slt_u   r29, r1, r29
1036	{
1037	 mnz    r1, r29, r1
1038	 move   r29, zero
1039	}
1040	iret
1041
1042	/*
1043	 * Not a syscall, so restore caller-saved registers.
1044	 * First kick off a load for cache line 1, which we're touching
1045	 * for the first time here.
1046	 */
1047	.align 64
10481:	pop_reg r29, sp, PTREGS_OFFSET_REG(1) - PTREGS_OFFSET_REG(29)
1049	pop_reg r1
1050	pop_reg r2
1051	pop_reg r3
1052	pop_reg r4
1053	pop_reg r5
1054	pop_reg r6
1055	pop_reg r7
1056	pop_reg r8
1057	pop_reg r9
1058	pop_reg r10
1059	pop_reg r11
1060	pop_reg r12
1061	pop_reg r13
1062	pop_reg r14
1063	pop_reg r15
1064	pop_reg r16
1065	pop_reg r17
1066	pop_reg r18
1067	pop_reg r19
1068	pop_reg r20
1069	pop_reg r21
1070	pop_reg r22
1071	pop_reg r23
1072	pop_reg r24
1073	pop_reg r25
1074	pop_reg r26
1075	pop_reg r27
1076	pop_reg r28, sp, PTREGS_OFFSET_LR - PTREGS_OFFSET_REG(28)
1077	/* r29 already restored above */
1078	bnz     lr, .Lkernel_return
1079	pop_reg lr, sp, PTREGS_OFFSET_TP - PTREGS_OFFSET_LR
1080	pop_reg tp, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_TP
1081	lw      sp, sp
1082	iret
1083
1084	/*
1085	 * We can't restore tp when in kernel mode, since a thread might
1086	 * have migrated from another cpu and brought a stale tp value.
1087	 */
1088.Lkernel_return:
1089	pop_reg lr, sp, PTREGS_OFFSET_SP - PTREGS_OFFSET_LR
1090	lw      sp, sp
1091	iret
1092
1093	/* Restore callee-saved registers from r34 to r51. */
1094.Lrestore_callees:
1095	addli  sp, sp, PTREGS_OFFSET_REG(34) - PTREGS_OFFSET_REG(29)
1096	pop_reg r34
1097	pop_reg r35
1098	pop_reg r36
1099	pop_reg r37
1100	pop_reg r38
1101	pop_reg r39
1102	pop_reg r40
1103	pop_reg r41
1104	pop_reg r42
1105	pop_reg r43
1106	pop_reg r44
1107	pop_reg r45
1108	pop_reg r46
1109	pop_reg r47
1110	pop_reg r48
1111	pop_reg r49
1112	pop_reg r50
1113	pop_reg r51, sp, PTREGS_OFFSET_REG(29) - PTREGS_OFFSET_REG(51)
1114	j .Lcontinue_restore_regs
1115	STD_ENDPROC(interrupt_return)
1116
1117	/*
1118	 * Some interrupts don't check for single stepping
1119	 */
1120	.pushsection .text.handle_interrupt_no_single_step,"ax"
1121handle_interrupt_no_single_step:
1122	finish_interrupt_save handle_interrupt_no_single_step
1123	{
1124	 jalr   r0
1125	 PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
1126	}
1127	FEEDBACK_REENTER(handle_interrupt_no_single_step)
1128	{
1129	 movei  r30, 0   /* not an NMI */
1130	 j      interrupt_return
1131	}
1132	STD_ENDPROC(handle_interrupt_no_single_step)
1133
1134	/*
1135	 * "NMI" interrupts mask ALL interrupts before calling the
1136	 * handler, and don't check thread flags, etc., on the way
1137	 * back out.  In general, the only things we do here for NMIs
1138	 * are the register save/restore, fixing the PC if we were
1139	 * doing single step, and the dataplane kernel-TLB management.
1140	 * We don't (for example) deal with start/stop of the sched tick.
1141	 */
1142	.pushsection .text.handle_nmi,"ax"
1143handle_nmi:
1144	finish_interrupt_save handle_nmi
1145	check_single_stepping normal, .Ldispatch_nmi
1146.Ldispatch_nmi:
1147	{
1148	 jalr   r0
1149	 PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
1150	}
1151	FEEDBACK_REENTER(handle_nmi)
 
 
 
 
1152	j       interrupt_return
1153	STD_ENDPROC(handle_nmi)
1154
1155	/*
1156	 * Parallel code for syscalls to handle_interrupt.
1157	 */
1158	.pushsection .text.handle_syscall,"ax"
1159handle_syscall:
1160	finish_interrupt_save handle_syscall
1161
1162	/*
1163	 * Check for if we are single stepping in user level. If so, then
1164	 * we need to restore the PC.
1165	 */
1166	check_single_stepping syscall, .Ldispatch_syscall
1167.Ldispatch_syscall:
1168
1169	/* Enable irqs. */
1170	TRACE_IRQS_ON
1171	IRQ_ENABLE(r20, r21)
1172
1173	/* Bump the counter for syscalls made on this tile. */
1174	moveli  r20, lo16(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET)
1175	auli    r20, r20, ha16(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET)
1176	add     r20, r20, tp
1177	lw      r21, r20
1178	addi    r21, r21, 1
1179	sw      r20, r21
 
 
 
1180
1181	/* Trace syscalls, if requested. */
1182	GET_THREAD_INFO(r31)
1183	addi	r31, r31, THREAD_INFO_FLAGS_OFFSET
1184	lw	r30, r31
1185	andi    r30, r30, _TIF_SYSCALL_TRACE
1186	bzt	r30, .Lrestore_syscall_regs
1187	jal	do_syscall_trace
 
 
 
1188	FEEDBACK_REENTER(handle_syscall)
1189
1190	/*
1191	 * We always reload our registers from the stack at this
1192	 * point.  They might be valid, if we didn't build with
1193	 * TRACE_IRQFLAGS, and this isn't a dataplane tile, and we're not
1194	 * doing syscall tracing, but there are enough cases now that it
1195	 * seems simplest just to do the reload unconditionally.
1196	 */
1197.Lrestore_syscall_regs:
1198	PTREGS_PTR(r11, PTREGS_OFFSET_REG(0))
1199	pop_reg r0, r11
1200	pop_reg r1, r11
1201	pop_reg r2, r11
1202	pop_reg r3, r11
1203	pop_reg r4, r11
1204	pop_reg r5, r11, PTREGS_OFFSET_SYSCALL - PTREGS_OFFSET_REG(5)
1205	pop_reg TREG_SYSCALL_NR_NAME, r11
1206
1207	/* Ensure that the syscall number is within the legal range. */
1208	moveli  r21, __NR_syscalls
1209	{
1210	 slt_u  r21, TREG_SYSCALL_NR_NAME, r21
1211	 moveli r20, lo16(sys_call_table)
1212	}
1213	{
1214	 bbns   r21, .Linvalid_syscall
1215	 auli   r20, r20, ha16(sys_call_table)
1216	}
1217	s2a     r20, TREG_SYSCALL_NR_NAME, r20
1218	lw      r20, r20
1219
1220	/* Jump to syscall handler. */
1221	jalr    r20
1222.Lhandle_syscall_link: /* value of "lr" after "jalr r20" above */
1223
1224	/*
1225	 * Write our r0 onto the stack so it gets restored instead
1226	 * of whatever the user had there before.
1227	 */
1228	PTREGS_PTR(r29, PTREGS_OFFSET_REG(0))
1229	sw      r29, r0
1230
1231.Lsyscall_sigreturn_skip:
1232	FEEDBACK_REENTER(handle_syscall)
1233
1234	/* Do syscall trace again, if requested. */
1235	lw	r30, r31
1236	andi    r30, r30, _TIF_SYSCALL_TRACE
1237	bzt     r30, 1f
1238	jal	do_syscall_trace
 
 
 
1239	FEEDBACK_REENTER(handle_syscall)
12401:	j       .Lresume_userspace   /* jump into middle of interrupt_return */
 
 
 
1241
1242.Linvalid_syscall:
1243	/* Report an invalid syscall back to the user program */
1244	{
1245	 PTREGS_PTR(r29, PTREGS_OFFSET_REG(0))
1246	 movei  r28, -ENOSYS
1247	}
1248	sw      r29, r28
1249	j       .Lresume_userspace   /* jump into middle of interrupt_return */
 
 
 
1250	STD_ENDPROC(handle_syscall)
1251
1252	/* Return the address for oprofile to suppress in backtraces. */
1253STD_ENTRY_SECTION(handle_syscall_link_address, .text.handle_syscall)
1254	lnk     r0
1255	{
1256	 addli  r0, r0, .Lhandle_syscall_link - .
1257	 jrp    lr
1258	}
1259	STD_ENDPROC(handle_syscall_link_address)
1260
1261STD_ENTRY(ret_from_fork)
1262	jal     sim_notify_fork
1263	jal     schedule_tail
1264	FEEDBACK_REENTER(ret_from_fork)
1265	j       .Lresume_userspace   /* jump into middle of interrupt_return */
 
 
 
1266	STD_ENDPROC(ret_from_fork)
1267
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1268	/*
1269	 * Code for ill interrupt.
1270	 */
1271	.pushsection .text.handle_ill,"ax"
1272handle_ill:
1273	finish_interrupt_save handle_ill
1274
1275	/*
1276	 * Check for if we are single stepping in user level. If so, then
1277	 * we need to restore the PC.
1278	 */
1279	check_single_stepping ill, .Ldispatch_normal_ill
1280
1281	{
1282	 /* See if the PC is the 1st bundle in the buffer */
1283	 seq    r25, r27, r26
1284
1285	 /* Point to the 2nd bundle in the buffer */
1286	 addi   r26, r26, 8
1287	}
1288	{
1289	 /* Point to the original pc */
1290	 addi   r24, r29, SINGLESTEP_STATE_ORIG_PC_OFFSET
1291
1292	 /* Branch if the PC is the 1st bundle in the buffer */
1293	 bnz    r25, 3f
1294	}
1295	{
1296	 /* See if the PC is the 2nd bundle of the buffer */
1297	 seq    r25, r27, r26
1298
1299	 /* Set PC to next instruction */
1300	 addi   r24, r29, SINGLESTEP_STATE_NEXT_PC_OFFSET
1301	}
1302	{
1303	 /* Point to flags */
1304	 addi   r25, r29, SINGLESTEP_STATE_FLAGS_OFFSET
1305
1306	 /* Branch if PC is in the second bundle */
1307	 bz     r25, 2f
1308	}
1309	/* Load flags */
1310	lw      r25, r25
1311	{
1312	 /*
1313	  * Get the offset for the register to restore
1314	  * Note: the lower bound is 2, so we have implicit scaling by 4.
1315	  *  No multiplication of the register number by the size of a register
1316	  *  is needed.
1317	  */
1318	 mm     r27, r25, zero, SINGLESTEP_STATE_TARGET_LB, \
1319		SINGLESTEP_STATE_TARGET_UB
1320
1321	 /* Mask Rewrite_LR */
1322	 andi   r25, r25, SINGLESTEP_STATE_MASK_UPDATE
1323	}
1324	{
1325	 addi   r29, r29, SINGLESTEP_STATE_UPDATE_VALUE_OFFSET
1326
1327	 /* Don't rewrite temp register */
1328	 bz     r25, 3f
1329	}
1330	{
1331	 /* Get the temp value */
1332	 lw     r29, r29
1333
1334	 /* Point to where the register is stored */
1335	 add    r27, r27, sp
1336	}
1337
1338	/* Add in the C ABI save area size to the register offset */
1339	addi    r27, r27, C_ABI_SAVE_AREA_SIZE
1340
1341	/* Restore the user's register with the temp value */
1342	sw      r27, r29
1343	j       3f
1344
13452:
1346	/* Must be in the third bundle */
1347	addi    r24, r29, SINGLESTEP_STATE_BRANCH_NEXT_PC_OFFSET
1348
13493:
1350	/* set PC and continue */
1351	lw      r26, r24
1352	sw      r28, r26
 
 
 
1353
1354	/*
1355	 * Clear TIF_SINGLESTEP to prevent recursion if we execute an ill.
1356	 * The normal non-arch flow redundantly clears TIF_SINGLESTEP, but we
1357	 * need to clear it here and can't really impose on all other arches.
1358	 * So what's another write between friends?
1359	 */
1360	GET_THREAD_INFO(r0)
1361
1362	addi    r1, r0, THREAD_INFO_FLAGS_OFFSET
1363	{
1364	 lw     r2, r1
1365	 addi   r0, r0, THREAD_INFO_TASK_OFFSET  /* currently a no-op */
1366	}
1367	andi    r2, r2, ~_TIF_SINGLESTEP
1368	sw      r1, r2
1369
1370	/* Issue a sigtrap */
1371	{
1372	 lw     r0, r0          /* indirect thru thread_info to get task_info*/
1373	 addi   r1, sp, C_ABI_SAVE_AREA_SIZE  /* put ptregs pointer into r1 */
1374	 move   r2, zero        /* load error code into r2 */
1375	}
1376
1377	jal     send_sigtrap    /* issue a SIGTRAP */
1378	FEEDBACK_REENTER(handle_ill)
1379	j       .Lresume_userspace   /* jump into middle of interrupt_return */
 
 
 
1380
1381.Ldispatch_normal_ill:
1382	{
1383	 jalr   r0
1384	 PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
1385	}
1386	FEEDBACK_REENTER(handle_ill)
1387	{
1388	 movei  r30, 0   /* not an NMI */
1389	 j      interrupt_return
1390	}
1391	STD_ENDPROC(handle_ill)
1392
1393/* Various stub interrupt handlers and syscall handlers */
1394
1395STD_ENTRY_LOCAL(_kernel_double_fault)
1396	mfspr   r1, SPR_EX_CONTEXT_K_0
1397	move    r2, lr
1398	move    r3, sp
1399	move    r4, r52
1400	addi    sp, sp, -C_ABI_SAVE_AREA_SIZE
1401	j       kernel_double_fault
1402	STD_ENDPROC(_kernel_double_fault)
1403
1404STD_ENTRY_LOCAL(bad_intr)
1405	mfspr   r2, SPR_EX_CONTEXT_K_0
1406	panic   "Unhandled interrupt %#x: PC %#lx"
1407	STD_ENDPROC(bad_intr)
1408
1409/* Put address of pt_regs in reg and jump. */
1410#define PTREGS_SYSCALL(x, reg)                          \
1411	STD_ENTRY(_##x);                                \
1412	{                                               \
1413	 PTREGS_PTR(reg, PTREGS_OFFSET_BASE);           \
1414	 j      x                                       \
1415	};                                              \
1416	STD_ENDPROC(_##x)
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(sys_execve, r3)
1434PTREGS_SYSCALL(sys_sigaltstack, r2)
1435PTREGS_SYSCALL_SIGRETURN(sys_rt_sigreturn, r0)
1436PTREGS_SYSCALL(sys_cmpxchg_badaddr, r1)
1437
1438/* Save additional callee-saves to pt_regs, put address in r4 and jump. */
1439STD_ENTRY(_sys_clone)
1440	push_extra_callee_saves r4
1441	j       sys_clone
1442	STD_ENDPROC(_sys_clone)
1443
1444/*
1445 * This entrypoint is taken for the cmpxchg and atomic_update fast
1446 * swints.  We may wish to generalize it to other fast swints at some
1447 * point, but for now there are just two very similar ones, which
1448 * makes it faster.
1449 *
1450 * The fast swint code is designed to have a small footprint.  It does
1451 * not save or restore any GPRs, counting on the caller-save registers
1452 * to be available to it on entry.  It does not modify any callee-save
1453 * registers (including "lr").  It does not check what PL it is being
1454 * called at, so you'd better not call it other than at PL0.
1455 * The <atomic.h> wrapper assumes it only clobbers r20-r29, so if
1456 * it ever is necessary to use more registers, be aware.
1457 *
1458 * It does not use the stack, but since it might be re-interrupted by
1459 * a page fault which would assume the stack was valid, it does
1460 * save/restore the stack pointer and zero it out to make sure it gets reset.
1461 * Since we always keep interrupts disabled, the hypervisor won't
1462 * clobber our EX_CONTEXT_K_x registers, so we don't save/restore them
1463 * (other than to advance the PC on return).
1464 *
1465 * We have to manually validate the user vs kernel address range
1466 * (since at PL1 we can read/write both), and for performance reasons
1467 * we don't allow cmpxchg on the fc000000 memory region, since we only
1468 * validate that the user address is below PAGE_OFFSET.
1469 *
1470 * We place it in the __HEAD section to ensure it is relatively
1471 * near to the intvec_SWINT_1 code (reachable by a conditional branch).
1472 *
1473 * Our use of ATOMIC_LOCK_REG here must match do_page_fault_ics().
1474 *
1475 * As we do in lib/atomic_asm_32.S, we bypass a store if the value we
1476 * would store is the same as the value we just loaded.
1477 */
1478	__HEAD
1479	.align 64
1480	/* Align much later jump on the start of a cache line. */
1481#if !ATOMIC_LOCKS_FOUND_VIA_TABLE()
1482	nop
1483#if PAGE_SIZE >= 0x10000
1484	nop
1485#endif
1486#endif
1487ENTRY(sys_cmpxchg)
1488
1489	/*
1490	 * Save "sp" and set it zero for any possible page fault.
1491	 *
1492	 * HACK: We want to both zero sp and check r0's alignment,
1493	 * so we do both at once. If "sp" becomes nonzero we
1494	 * know r0 is unaligned and branch to the error handler that
1495	 * restores sp, so this is OK.
1496	 *
1497	 * ICS is disabled right now so having a garbage but nonzero
1498	 * sp is OK, since we won't execute any faulting instructions
1499	 * when it is nonzero.
1500	 */
1501	{
1502	 move   r27, sp
1503	 andi	sp, r0, 3
1504	}
1505
1506	/*
1507	 * Get the lock address in ATOMIC_LOCK_REG, and also validate that the
1508	 * address is less than PAGE_OFFSET, since that won't trap at PL1.
1509	 * We only use bits less than PAGE_SHIFT to avoid having to worry
1510	 * about aliasing among multiple mappings of the same physical page,
1511	 * and we ignore the low 3 bits so we have one lock that covers
1512	 * both a cmpxchg64() and a cmpxchg() on either its low or high word.
1513	 * NOTE: this must match __atomic_hashed_lock() in lib/atomic_32.c.
1514	 */
1515
1516#if (PAGE_OFFSET & 0xffff) != 0
1517# error Code here assumes PAGE_OFFSET can be loaded with just hi16()
1518#endif
1519
1520#if ATOMIC_LOCKS_FOUND_VIA_TABLE()
1521	{
1522	 /* Check for unaligned input. */
1523	 bnz    sp, .Lcmpxchg_badaddr
1524	 mm     r25, r0, zero, 3, PAGE_SHIFT-1
1525	}
1526	{
1527	 crc32_32 r25, zero, r25
1528	 moveli r21, lo16(atomic_lock_ptr)
1529	}
1530	{
1531	 auli   r21, r21, ha16(atomic_lock_ptr)
1532	 auli   r23, zero, hi16(PAGE_OFFSET)  /* hugepage-aligned */
1533	}
1534	{
1535	 shri	r20, r25, 32 - ATOMIC_HASH_L1_SHIFT
1536	 slt_u  r23, r0, r23
1537	 lw	r26, r0  /* see comment in the "#else" for the "lw r26". */
1538	}
1539	{
1540	 s2a    r21, r20, r21
1541	 bbns   r23, .Lcmpxchg_badaddr
1542	}
1543	{
1544	 lw     r21, r21
1545	 seqi	r23, TREG_SYSCALL_NR_NAME, __NR_FAST_cmpxchg64
1546	 andi	r25, r25, ATOMIC_HASH_L2_SIZE - 1
1547	}
1548	{
1549	 /* Branch away at this point if we're doing a 64-bit cmpxchg. */
1550	 bbs    r23, .Lcmpxchg64
1551	 andi   r23, r0, 7       /* Precompute alignment for cmpxchg64. */
1552	}
1553	{
1554	 s2a	ATOMIC_LOCK_REG_NAME, r25, r21
1555	 j      .Lcmpxchg32_tns   /* see comment in the #else for the jump. */
1556	}
1557
1558#else /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */
1559	{
1560	 /* Check for unaligned input. */
1561	 bnz    sp, .Lcmpxchg_badaddr
1562	 auli   r23, zero, hi16(PAGE_OFFSET)  /* hugepage-aligned */
1563	}
1564	{
1565	 /*
1566	  * Slide bits into position for 'mm'. We want to ignore
1567	  * the low 3 bits of r0, and consider only the next
1568	  * ATOMIC_HASH_SHIFT bits.
1569	  * Because of C pointer arithmetic, we want to compute this:
1570	  *
1571	  * ((char*)atomic_locks +
1572	  *  (((r0 >> 3) & (1 << (ATOMIC_HASH_SIZE - 1))) << 2))
1573	  *
1574	  * Instead of two shifts we just ">> 1", and use 'mm'
1575	  * to ignore the low and high bits we don't want.
1576	  */
1577	 shri	r25, r0, 1
1578
1579	 slt_u  r23, r0, r23
1580
1581	 /*
1582	  * Ensure that the TLB is loaded before we take out the lock.
1583	  * On tilepro, this will start fetching the value all the way
1584	  * into our L1 as well (and if it gets modified before we
1585	  * grab the lock, it will be invalidated from our cache
1586	  * before we reload it).  On tile64, we'll start fetching it
1587	  * into our L1 if we're the home, and if we're not, we'll
1588	  * still at least start fetching it into the home's L2.
1589	  */
1590	 lw	r26, r0
1591	}
1592	{
1593	 auli	r21, zero, ha16(atomic_locks)
1594
1595	 bbns   r23, .Lcmpxchg_badaddr
1596	}
1597#if PAGE_SIZE < 0x10000
1598	/* atomic_locks is page-aligned so for big pages we don't need this. */
1599	addli   r21, r21, lo16(atomic_locks)
1600#endif
1601	{
1602	 /*
1603	  * Insert the hash bits into the page-aligned pointer.
1604	  * ATOMIC_HASH_SHIFT is so big that we don't actually hash
1605	  * the unmasked address bits, as that may cause unnecessary
1606	  * collisions.
1607	  */
1608	 mm	ATOMIC_LOCK_REG_NAME, r25, r21, 2, (ATOMIC_HASH_SHIFT + 2) - 1
1609
1610	 seqi	r23, TREG_SYSCALL_NR_NAME, __NR_FAST_cmpxchg64
1611	}
1612	{
1613	 /* Branch away at this point if we're doing a 64-bit cmpxchg. */
1614	 bbs    r23, .Lcmpxchg64
1615	 andi   r23, r0, 7       /* Precompute alignment for cmpxchg64. */
1616	}
1617	{
1618	 /*
1619	  * We very carefully align the code that actually runs with
1620	  * the lock held (twelve bundles) so that we know it is all in
1621	  * the icache when we start.  This instruction (the jump) is
1622	  * at the start of the first cache line, address zero mod 64;
1623	  * we jump to the very end of the second cache line to get that
1624	  * line loaded in the icache, then fall through to issue the tns
1625	  * in the third cache line, at which point it's all cached.
1626	  * Note that is for performance, not correctness.
1627	  */
1628	 j      .Lcmpxchg32_tns
1629	}
1630
1631#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */
1632
1633/* Symbol for do_page_fault_ics() to use to compare against the PC. */
1634.global __sys_cmpxchg_grab_lock
1635__sys_cmpxchg_grab_lock:
1636
1637	/*
1638	 * Perform the actual cmpxchg or atomic_update.
1639	 */
1640.Ldo_cmpxchg32:
1641	{
1642	 lw     r21, r0
1643	 seqi	r23, TREG_SYSCALL_NR_NAME, __NR_FAST_atomic_update
1644	 move	r24, r2
1645	}
1646	{
1647	 seq    r22, r21, r1     /* See if cmpxchg matches. */
1648	 and	r25, r21, r1     /* If atomic_update, compute (*mem & mask) */
1649	}
1650	{
1651	 or	r22, r22, r23    /* Skip compare branch for atomic_update. */
1652	 add	r25, r25, r2     /* Compute (*mem & mask) + addend. */
1653	}
1654	{
1655	 mvnz	r24, r23, r25    /* Use atomic_update value if appropriate. */
1656	 bbns   r22, .Lcmpxchg32_nostore
1657	}
1658	seq     r22, r24, r21    /* Are we storing the value we loaded? */
1659	bbs     r22, .Lcmpxchg32_nostore
1660	sw      r0, r24
1661
1662	/* The following instruction is the start of the second cache line. */
1663	/* Do slow mtspr here so the following "mf" waits less. */
1664	{
1665	 move   sp, r27
1666	 mtspr  SPR_EX_CONTEXT_K_0, r28
1667	}
1668	mf
1669
1670	{
1671	 move   r0, r21
1672	 sw     ATOMIC_LOCK_REG_NAME, zero
1673	}
1674	iret
1675
1676	/* Duplicated code here in the case where we don't overlap "mf" */
1677.Lcmpxchg32_nostore:
1678	{
1679	 move   r0, r21
1680	 sw     ATOMIC_LOCK_REG_NAME, zero
1681	}
1682	{
1683	 move   sp, r27
1684	 mtspr  SPR_EX_CONTEXT_K_0, r28
1685	}
1686	iret
1687
1688	/*
1689	 * The locking code is the same for 32-bit cmpxchg/atomic_update,
1690	 * and for 64-bit cmpxchg.  We provide it as a macro and put
1691	 * it into both versions.  We can't share the code literally
1692	 * since it depends on having the right branch-back address.
1693	 */
1694	.macro  cmpxchg_lock, bitwidth
1695
1696	/* Lock; if we succeed, jump back up to the read-modify-write. */
1697#ifdef CONFIG_SMP
1698	tns     r21, ATOMIC_LOCK_REG_NAME
1699#else
1700	/*
1701	 * Non-SMP preserves all the lock infrastructure, to keep the
1702	 * code simpler for the interesting (SMP) case.  However, we do
1703	 * one small optimization here and in atomic_asm.S, which is
1704	 * to fake out acquiring the actual lock in the atomic_lock table.
1705	 */
1706	movei	r21, 0
1707#endif
1708
1709	/* Issue the slow SPR here while the tns result is in flight. */
1710	mfspr   r28, SPR_EX_CONTEXT_K_0
1711
1712	{
1713	 addi   r28, r28, 8    /* return to the instruction after the swint1 */
1714	 bzt    r21, .Ldo_cmpxchg\bitwidth
1715	}
1716	/*
1717	 * The preceding instruction is the last thing that must be
1718	 * hot in the icache before we do the "tns" above.
1719	 */
1720
1721#ifdef CONFIG_SMP
1722	/*
1723	 * We failed to acquire the tns lock on our first try.  Now use
1724	 * bounded exponential backoff to retry, like __atomic_spinlock().
1725	 */
1726	{
1727	 moveli r23, 2048       /* maximum backoff time in cycles */
1728	 moveli r25, 32         /* starting backoff time in cycles */
1729	}
17301:	mfspr   r26, CYCLE_LOW  /* get start point for this backoff */
17312:	mfspr   r22, CYCLE_LOW  /* test to see if we've backed off enough */
1732	sub     r22, r22, r26
1733	slt     r22, r22, r25
1734	bbst    r22, 2b
1735	{
1736	 shli   r25, r25, 1     /* double the backoff; retry the tns */
1737	 tns    r21, ATOMIC_LOCK_REG_NAME
1738	}
1739	slt     r26, r23, r25   /* is the proposed backoff too big? */
1740	{
1741	 mvnz   r25, r26, r23
1742	 bzt    r21, .Ldo_cmpxchg\bitwidth
1743	}
1744	j       1b
1745#endif /* CONFIG_SMP */
1746	.endm
1747
1748.Lcmpxchg32_tns:
1749	/*
1750	 * This is the last instruction on the second cache line.
1751	 * The nop here loads the second line, then we fall through
1752	 * to the tns to load the third line before we take the lock.
1753	 */
1754	nop
1755	cmpxchg_lock 32
1756
1757	/*
1758	 * This code is invoked from sys_cmpxchg after most of the
1759	 * preconditions have been checked.  We still need to check
1760	 * that r0 is 8-byte aligned, since if it's not we won't
1761	 * actually be atomic.  However, ATOMIC_LOCK_REG has the atomic
1762	 * lock pointer and r27/r28 have the saved SP/PC.
1763	 * r23 is holding "r0 & 7" so we can test for alignment.
1764	 * The compare value is in r2/r3; the new value is in r4/r5.
1765	 * On return, we must put the old value in r0/r1.
1766	 */
1767	.align 64
1768.Lcmpxchg64:
1769	{
1770#if ATOMIC_LOCKS_FOUND_VIA_TABLE()
1771	 s2a	ATOMIC_LOCK_REG_NAME, r25, r21
1772#endif
1773	 bzt     r23, .Lcmpxchg64_tns
1774	}
1775	j       .Lcmpxchg_badaddr
1776
1777.Ldo_cmpxchg64:
1778	{
1779	 lw     r21, r0
1780	 addi   r25, r0, 4
1781	}
1782	{
1783	 lw     r1, r25
1784	}
1785	seq     r26, r21, r2
1786	{
1787	 bz     r26, .Lcmpxchg64_mismatch
1788	 seq    r26, r1, r3
1789	}
1790	{
1791	 bz     r26, .Lcmpxchg64_mismatch
1792	}
1793	sw      r0, r4
1794	sw      r25, r5
1795
1796	/*
1797	 * The 32-bit path provides optimized "match" and "mismatch"
1798	 * iret paths, but we don't have enough bundles in this cache line
1799	 * to do that, so we just make even the "mismatch" path do an "mf".
1800	 */
1801.Lcmpxchg64_mismatch:
1802	{
1803	 move   sp, r27
1804	 mtspr  SPR_EX_CONTEXT_K_0, r28
1805	}
1806	mf
1807	{
1808	 move   r0, r21
1809	 sw     ATOMIC_LOCK_REG_NAME, zero
1810	}
1811	iret
1812
1813.Lcmpxchg64_tns:
1814	cmpxchg_lock 64
1815
1816
1817	/*
1818	 * Reset sp and revector to sys_cmpxchg_badaddr(), which will
1819	 * just raise the appropriate signal and exit.  Doing it this
1820	 * way means we don't have to duplicate the code in intvec.S's
1821	 * int_hand macro that locates the top of the stack.
1822	 */
1823.Lcmpxchg_badaddr:
1824	{
1825	 moveli TREG_SYSCALL_NR_NAME, __NR_cmpxchg_badaddr
1826	 move   sp, r27
1827	}
1828	j       intvec_SWINT_1
1829	ENDPROC(sys_cmpxchg)
1830	ENTRY(__sys_cmpxchg_end)
1831
1832
1833/* The single-step support may need to read all the registers. */
1834int_unalign:
1835	push_extra_callee_saves r0
1836	j       do_trap
1837
1838/* Include .intrpt1 array of interrupt vectors */
1839	.section ".intrpt1", "ax"
1840
1841#define op_handle_perf_interrupt bad_intr
1842#define op_handle_aux_perf_interrupt bad_intr
 
1843
1844#ifndef CONFIG_HARDWALL
1845#define do_hardwall_trap bad_intr
1846#endif
1847
1848	int_hand     INT_ITLB_MISS, ITLB_MISS, \
1849		     do_page_fault, handle_interrupt_no_single_step
1850	int_hand     INT_MEM_ERROR, MEM_ERROR, bad_intr
1851	int_hand     INT_ILL, ILL, do_trap, handle_ill
1852	int_hand     INT_GPV, GPV, do_trap
1853	int_hand     INT_SN_ACCESS, SN_ACCESS, do_trap
1854	int_hand     INT_IDN_ACCESS, IDN_ACCESS, do_trap
1855	int_hand     INT_UDN_ACCESS, UDN_ACCESS, do_trap
1856	int_hand     INT_IDN_REFILL, IDN_REFILL, bad_intr
1857	int_hand     INT_UDN_REFILL, UDN_REFILL, bad_intr
1858	int_hand     INT_IDN_COMPLETE, IDN_COMPLETE, bad_intr
1859	int_hand     INT_UDN_COMPLETE, UDN_COMPLETE, bad_intr
1860	int_hand     INT_SWINT_3, SWINT_3, do_trap
1861	int_hand     INT_SWINT_2, SWINT_2, do_trap
1862	int_hand     INT_SWINT_1, SWINT_1, SYSCALL, handle_syscall
1863	int_hand     INT_SWINT_0, SWINT_0, do_trap
1864	int_hand     INT_UNALIGN_DATA, UNALIGN_DATA, int_unalign
1865	int_hand     INT_DTLB_MISS, DTLB_MISS, do_page_fault
1866	int_hand     INT_DTLB_ACCESS, DTLB_ACCESS, do_page_fault
1867	int_hand     INT_DMATLB_MISS, DMATLB_MISS, do_page_fault
1868	int_hand     INT_DMATLB_ACCESS, DMATLB_ACCESS, do_page_fault
1869	int_hand     INT_SNITLB_MISS, SNITLB_MISS, do_page_fault
1870	int_hand     INT_SN_NOTIFY, SN_NOTIFY, bad_intr
1871	int_hand     INT_SN_FIREWALL, SN_FIREWALL, do_hardwall_trap
1872	int_hand     INT_IDN_FIREWALL, IDN_FIREWALL, bad_intr
1873	int_hand     INT_UDN_FIREWALL, UDN_FIREWALL, do_hardwall_trap
1874	int_hand     INT_TILE_TIMER, TILE_TIMER, do_timer_interrupt
1875	int_hand     INT_IDN_TIMER, IDN_TIMER, bad_intr
1876	int_hand     INT_UDN_TIMER, UDN_TIMER, bad_intr
1877	int_hand     INT_DMA_NOTIFY, DMA_NOTIFY, bad_intr
1878	int_hand     INT_IDN_CA, IDN_CA, bad_intr
1879	int_hand     INT_UDN_CA, UDN_CA, bad_intr
1880	int_hand     INT_IDN_AVAIL, IDN_AVAIL, bad_intr
1881	int_hand     INT_UDN_AVAIL, UDN_AVAIL, bad_intr
1882	int_hand     INT_PERF_COUNT, PERF_COUNT, \
1883		     op_handle_perf_interrupt, handle_nmi
1884	int_hand     INT_INTCTRL_3, INTCTRL_3, bad_intr
1885#if CONFIG_KERNEL_PL == 2
1886	dc_dispatch  INT_INTCTRL_2, INTCTRL_2
1887	int_hand     INT_INTCTRL_1, INTCTRL_1, bad_intr
1888#else
1889	int_hand     INT_INTCTRL_2, INTCTRL_2, bad_intr
1890	dc_dispatch  INT_INTCTRL_1, INTCTRL_1
1891#endif
1892	int_hand     INT_INTCTRL_0, INTCTRL_0, bad_intr
1893	int_hand     INT_MESSAGE_RCV_DWNCL, MESSAGE_RCV_DWNCL, \
1894		     hv_message_intr
1895	int_hand     INT_DEV_INTR_DWNCL, DEV_INTR_DWNCL, \
1896		     tile_dev_intr
1897	int_hand     INT_I_ASID, I_ASID, bad_intr
1898	int_hand     INT_D_ASID, D_ASID, bad_intr
1899	int_hand     INT_DMATLB_MISS_DWNCL, DMATLB_MISS_DWNCL, \
1900		     do_page_fault
1901	int_hand     INT_SNITLB_MISS_DWNCL, SNITLB_MISS_DWNCL, \
1902		     do_page_fault
1903	int_hand     INT_DMATLB_ACCESS_DWNCL, DMATLB_ACCESS_DWNCL, \
1904		     do_page_fault
1905	int_hand     INT_SN_CPL, SN_CPL, bad_intr
1906	int_hand     INT_DOUBLE_FAULT, DOUBLE_FAULT, do_trap
1907#if CHIP_HAS_AUX_PERF_COUNTERS()
1908	int_hand     INT_AUX_PERF_COUNT, AUX_PERF_COUNT, \
1909		     op_handle_aux_perf_interrupt, handle_nmi
1910#endif
1911
1912	/* Synthetic interrupt delivered only by the simulator */
1913	int_hand     INT_BREAKPOINT, BREAKPOINT, do_breakpoint