2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (C) 1994 - 1999, 2000, 01, 06 Ralf Baechle
7 * Copyright (C) 1995, 1996 Paul M. Antoine
8 * Copyright (C) 1998 Ulf Carlsson
9 * Copyright (C) 1999 Silicon Graphics, Inc.
10 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
11 * Copyright (C) 2002, 2003, 2004, 2005, 2007 Maciej W. Rozycki
12 * Copyright (C) 2000, 2001, 2012 MIPS Technologies, Inc. All rights reserved.
13 * Copyright (C) 2014, Imagination Technologies Ltd.
15 #include <linux/bitops.h>
16 #include <linux/bug.h>
17 #include <linux/compiler.h>
18 #include <linux/context_tracking.h>
19 #include <linux/cpu_pm.h>
20 #include <linux/kexec.h>
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
25 #include <linux/sched.h>
26 #include <linux/smp.h>
27 #include <linux/spinlock.h>
28 #include <linux/kallsyms.h>
29 #include <linux/bootmem.h>
30 #include <linux/interrupt.h>
31 #include <linux/ptrace.h>
32 #include <linux/kgdb.h>
33 #include <linux/kdebug.h>
34 #include <linux/kprobes.h>
35 #include <linux/notifier.h>
36 #include <linux/kdb.h>
37 #include <linux/irq.h>
38 #include <linux/perf_event.h>
40 #include <asm/bootinfo.h>
41 #include <asm/branch.h>
42 #include <asm/break.h>
45 #include <asm/cpu-type.h>
48 #include <asm/fpu_emulator.h>
50 #include <asm/mips-r2-to-r6-emul.h>
51 #include <asm/mipsregs.h>
52 #include <asm/mipsmtregs.h>
53 #include <asm/module.h>
55 #include <asm/pgtable.h>
56 #include <asm/ptrace.h>
57 #include <asm/sections.h>
58 #include <asm/tlbdebug.h>
59 #include <asm/traps.h>
60 #include <asm/uaccess.h>
61 #include <asm/watch.h>
62 #include <asm/mmu_context.h>
63 #include <asm/types.h>
64 #include <asm/stacktrace.h>
67 extern void check_wait(void);
68 extern asmlinkage void rollback_handle_int(void);
69 extern asmlinkage void handle_int(void);
70 extern u32 handle_tlbl[];
71 extern u32 handle_tlbs[];
72 extern u32 handle_tlbm[];
73 extern asmlinkage void handle_adel(void);
74 extern asmlinkage void handle_ades(void);
75 extern asmlinkage void handle_ibe(void);
76 extern asmlinkage void handle_dbe(void);
77 extern asmlinkage void handle_sys(void);
78 extern asmlinkage void handle_bp(void);
79 extern asmlinkage void handle_ri(void);
80 extern asmlinkage void handle_ri_rdhwr_vivt(void);
81 extern asmlinkage void handle_ri_rdhwr(void);
82 extern asmlinkage void handle_cpu(void);
83 extern asmlinkage void handle_ov(void);
84 extern asmlinkage void handle_tr(void);
85 extern asmlinkage void handle_msa_fpe(void);
86 extern asmlinkage void handle_fpe(void);
87 extern asmlinkage void handle_ftlb(void);
88 extern asmlinkage void handle_msa(void);
89 extern asmlinkage void handle_mdmx(void);
90 extern asmlinkage void handle_watch(void);
91 extern asmlinkage void handle_mt(void);
92 extern asmlinkage void handle_dsp(void);
93 extern asmlinkage void handle_mcheck(void);
94 extern asmlinkage void handle_reserved(void);
95 extern void tlb_do_page_fault_0(void);
97 void (*board_be_init)(void);
98 int (*board_be_handler)(struct pt_regs *regs, int is_fixup);
99 void (*board_nmi_handler_setup)(void);
100 void (*board_ejtag_handler_setup)(void);
101 void (*board_bind_eic_interrupt)(int irq, int regset);
102 void (*board_ebase_setup)(void);
103 void(*board_cache_error_setup)(void);
105 static void show_raw_backtrace(unsigned long reg29)
107 unsigned long *sp = (unsigned long *)(reg29 & ~3);
110 printk("Call Trace:");
111 #ifdef CONFIG_KALLSYMS
114 while (!kstack_end(sp)) {
115 unsigned long __user *p =
116 (unsigned long __user *)(unsigned long)sp++;
117 if (__get_user(addr, p)) {
118 printk(" (Bad stack address)");
121 if (__kernel_text_address(addr))
127 #ifdef CONFIG_KALLSYMS
129 static int __init set_raw_show_trace(char *str)
134 __setup("raw_show_trace", set_raw_show_trace);
137 static void show_backtrace(struct task_struct *task, const struct pt_regs *regs)
139 unsigned long sp = regs->regs[29];
140 unsigned long ra = regs->regs[31];
141 unsigned long pc = regs->cp0_epc;
146 if (raw_show_trace || !__kernel_text_address(pc)) {
147 show_raw_backtrace(sp);
150 printk("Call Trace:\n");
153 pc = unwind_stack(task, &sp, pc, &ra);
159 * This routine abuses get_user()/put_user() to reference pointers
160 * with at least a bit of error checking ...
162 static void show_stacktrace(struct task_struct *task,
163 const struct pt_regs *regs)
165 const int field = 2 * sizeof(unsigned long);
168 unsigned long __user *sp = (unsigned long __user *)regs->regs[29];
172 while ((unsigned long) sp & (PAGE_SIZE - 1)) {
173 if (i && ((i % (64 / field)) == 0))
180 if (__get_user(stackdata, sp++)) {
181 printk(" (Bad stack address)");
185 printk(" %0*lx", field, stackdata);
189 show_backtrace(task, regs);
192 void show_stack(struct task_struct *task, unsigned long *sp)
196 regs.regs[29] = (unsigned long)sp;
200 if (task && task != current) {
201 regs.regs[29] = task->thread.reg29;
203 regs.cp0_epc = task->thread.reg31;
204 #ifdef CONFIG_KGDB_KDB
205 } else if (atomic_read(&kgdb_active) != -1 &&
207 memcpy(®s, kdb_current_regs, sizeof(regs));
208 #endif /* CONFIG_KGDB_KDB */
210 prepare_frametrace(®s);
213 show_stacktrace(task, ®s);
216 static void show_code(unsigned int __user *pc)
219 unsigned short __user *pc16 = NULL;
223 if ((unsigned long)pc & 1)
224 pc16 = (unsigned short __user *)((unsigned long)pc & ~1);
225 for(i = -3 ; i < 6 ; i++) {
227 if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) {
228 printk(" (Bad address in epc)\n");
231 printk("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>'));
235 static void __show_regs(const struct pt_regs *regs)
237 const int field = 2 * sizeof(unsigned long);
238 unsigned int cause = regs->cp0_cause;
241 show_regs_print_info(KERN_DEFAULT);
244 * Saved main processor registers
246 for (i = 0; i < 32; ) {
250 printk(" %0*lx", field, 0UL);
251 else if (i == 26 || i == 27)
252 printk(" %*s", field, "");
254 printk(" %0*lx", field, regs->regs[i]);
261 #ifdef CONFIG_CPU_HAS_SMARTMIPS
262 printk("Acx : %0*lx\n", field, regs->acx);
264 printk("Hi : %0*lx\n", field, regs->hi);
265 printk("Lo : %0*lx\n", field, regs->lo);
268 * Saved cp0 registers
270 printk("epc : %0*lx %pS\n", field, regs->cp0_epc,
271 (void *) regs->cp0_epc);
272 printk(" %s\n", print_tainted());
273 printk("ra : %0*lx %pS\n", field, regs->regs[31],
274 (void *) regs->regs[31]);
276 printk("Status: %08x ", (uint32_t) regs->cp0_status);
279 if (regs->cp0_status & ST0_KUO)
281 if (regs->cp0_status & ST0_IEO)
283 if (regs->cp0_status & ST0_KUP)
285 if (regs->cp0_status & ST0_IEP)
287 if (regs->cp0_status & ST0_KUC)
289 if (regs->cp0_status & ST0_IEC)
291 } else if (cpu_has_4kex) {
292 if (regs->cp0_status & ST0_KX)
294 if (regs->cp0_status & ST0_SX)
296 if (regs->cp0_status & ST0_UX)
298 switch (regs->cp0_status & ST0_KSU) {
303 printk("SUPERVISOR ");
312 if (regs->cp0_status & ST0_ERL)
314 if (regs->cp0_status & ST0_EXL)
316 if (regs->cp0_status & ST0_IE)
321 printk("Cause : %08x\n", cause);
323 cause = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
324 if (1 <= cause && cause <= 5)
325 printk("BadVA : %0*lx\n", field, regs->cp0_badvaddr);
327 printk("PrId : %08x (%s)\n", read_c0_prid(),
332 * FIXME: really the generic show_regs should take a const pointer argument.
334 void show_regs(struct pt_regs *regs)
336 __show_regs((struct pt_regs *)regs);
339 void show_registers(struct pt_regs *regs)
341 const int field = 2 * sizeof(unsigned long);
342 mm_segment_t old_fs = get_fs();
346 printk("Process %s (pid: %d, threadinfo=%p, task=%p, tls=%0*lx)\n",
347 current->comm, current->pid, current_thread_info(), current,
348 field, current_thread_info()->tp_value);
349 if (cpu_has_userlocal) {
352 tls = read_c0_userlocal();
353 if (tls != current_thread_info()->tp_value)
354 printk("*HwTLS: %0*lx\n", field, tls);
357 if (!user_mode(regs))
358 /* Necessary for getting the correct stack content */
360 show_stacktrace(current, regs);
361 show_code((unsigned int __user *) regs->cp0_epc);
366 static int regs_to_trapnr(struct pt_regs *regs)
368 return (regs->cp0_cause >> 2) & 0x1f;
371 static DEFINE_RAW_SPINLOCK(die_lock);
373 void __noreturn die(const char *str, struct pt_regs *regs)
375 static int die_counter;
380 if (notify_die(DIE_OOPS, str, regs, 0, regs_to_trapnr(regs),
381 SIGSEGV) == NOTIFY_STOP)
385 raw_spin_lock_irq(&die_lock);
388 printk("%s[#%d]:\n", str, ++die_counter);
389 show_registers(regs);
390 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
391 raw_spin_unlock_irq(&die_lock);
396 panic("Fatal exception in interrupt");
399 printk(KERN_EMERG "Fatal exception: panic in 5 seconds");
401 panic("Fatal exception");
404 if (regs && kexec_should_crash(current))
410 extern struct exception_table_entry __start___dbe_table[];
411 extern struct exception_table_entry __stop___dbe_table[];
414 " .section __dbe_table, \"a\"\n"
417 /* Given an address, look for it in the exception tables. */
418 static const struct exception_table_entry *search_dbe_tables(unsigned long addr)
420 const struct exception_table_entry *e;
422 e = search_extable(__start___dbe_table, __stop___dbe_table - 1, addr);
424 e = search_module_dbetables(addr);
428 asmlinkage void do_be(struct pt_regs *regs)
430 const int field = 2 * sizeof(unsigned long);
431 const struct exception_table_entry *fixup = NULL;
432 int data = regs->cp0_cause & 4;
433 int action = MIPS_BE_FATAL;
434 enum ctx_state prev_state;
436 prev_state = exception_enter();
437 /* XXX For now. Fixme, this searches the wrong table ... */
438 if (data && !user_mode(regs))
439 fixup = search_dbe_tables(exception_epc(regs));
442 action = MIPS_BE_FIXUP;
444 if (board_be_handler)
445 action = board_be_handler(regs, fixup != NULL);
448 case MIPS_BE_DISCARD:
452 regs->cp0_epc = fixup->nextinsn;
461 * Assume it would be too dangerous to continue ...
463 printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n",
464 data ? "Data" : "Instruction",
465 field, regs->cp0_epc, field, regs->regs[31]);
466 if (notify_die(DIE_OOPS, "bus error", regs, 0, regs_to_trapnr(regs),
467 SIGBUS) == NOTIFY_STOP)
470 die_if_kernel("Oops", regs);
471 force_sig(SIGBUS, current);
474 exception_exit(prev_state);
478 * ll/sc, rdhwr, sync emulation
481 #define OPCODE 0xfc000000
482 #define BASE 0x03e00000
483 #define RT 0x001f0000
484 #define OFFSET 0x0000ffff
485 #define LL 0xc0000000
486 #define SC 0xe0000000
487 #define SPEC0 0x00000000
488 #define SPEC3 0x7c000000
489 #define RD 0x0000f800
490 #define FUNC 0x0000003f
491 #define SYNC 0x0000000f
492 #define RDHWR 0x0000003b
494 /* microMIPS definitions */
495 #define MM_POOL32A_FUNC 0xfc00ffff
496 #define MM_RDHWR 0x00006b3c
497 #define MM_RS 0x001f0000
498 #define MM_RT 0x03e00000
501 * The ll_bit is cleared by r*_switch.S
505 struct task_struct *ll_task;
507 static inline int simulate_ll(struct pt_regs *regs, unsigned int opcode)
509 unsigned long value, __user *vaddr;
513 * analyse the ll instruction that just caused a ri exception
514 * and put the referenced address to addr.
517 /* sign extend offset */
518 offset = opcode & OFFSET;
522 vaddr = (unsigned long __user *)
523 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
525 if ((unsigned long)vaddr & 3)
527 if (get_user(value, vaddr))
532 if (ll_task == NULL || ll_task == current) {
541 regs->regs[(opcode & RT) >> 16] = value;
546 static inline int simulate_sc(struct pt_regs *regs, unsigned int opcode)
548 unsigned long __user *vaddr;
553 * analyse the sc instruction that just caused a ri exception
554 * and put the referenced address to addr.
557 /* sign extend offset */
558 offset = opcode & OFFSET;
562 vaddr = (unsigned long __user *)
563 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
564 reg = (opcode & RT) >> 16;
566 if ((unsigned long)vaddr & 3)
571 if (ll_bit == 0 || ll_task != current) {
579 if (put_user(regs->regs[reg], vaddr))
588 * ll uses the opcode of lwc0 and sc uses the opcode of swc0. That is both
589 * opcodes are supposed to result in coprocessor unusable exceptions if
590 * executed on ll/sc-less processors. That's the theory. In practice a
591 * few processors such as NEC's VR4100 throw reserved instruction exceptions
592 * instead, so we're doing the emulation thing in both exception handlers.
594 static int simulate_llsc(struct pt_regs *regs, unsigned int opcode)
596 if ((opcode & OPCODE) == LL) {
597 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
599 return simulate_ll(regs, opcode);
601 if ((opcode & OPCODE) == SC) {
602 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
604 return simulate_sc(regs, opcode);
607 return -1; /* Must be something else ... */
611 * Simulate trapping 'rdhwr' instructions to provide user accessible
612 * registers not implemented in hardware.
614 static int simulate_rdhwr(struct pt_regs *regs, int rd, int rt)
616 struct thread_info *ti = task_thread_info(current);
618 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
621 case 0: /* CPU number */
622 regs->regs[rt] = smp_processor_id();
624 case 1: /* SYNCI length */
625 regs->regs[rt] = min(current_cpu_data.dcache.linesz,
626 current_cpu_data.icache.linesz);
628 case 2: /* Read count register */
629 regs->regs[rt] = read_c0_count();
631 case 3: /* Count register resolution */
632 switch (current_cpu_type()) {
642 regs->regs[rt] = ti->tp_value;
649 static int simulate_rdhwr_normal(struct pt_regs *regs, unsigned int opcode)
651 if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) {
652 int rd = (opcode & RD) >> 11;
653 int rt = (opcode & RT) >> 16;
655 simulate_rdhwr(regs, rd, rt);
663 static int simulate_rdhwr_mm(struct pt_regs *regs, unsigned short opcode)
665 if ((opcode & MM_POOL32A_FUNC) == MM_RDHWR) {
666 int rd = (opcode & MM_RS) >> 16;
667 int rt = (opcode & MM_RT) >> 21;
668 simulate_rdhwr(regs, rd, rt);
676 static int simulate_sync(struct pt_regs *regs, unsigned int opcode)
678 if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC) {
679 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
684 return -1; /* Must be something else ... */
687 asmlinkage void do_ov(struct pt_regs *regs)
689 enum ctx_state prev_state;
692 prev_state = exception_enter();
693 die_if_kernel("Integer overflow", regs);
695 info.si_code = FPE_INTOVF;
696 info.si_signo = SIGFPE;
698 info.si_addr = (void __user *) regs->cp0_epc;
699 force_sig_info(SIGFPE, &info, current);
700 exception_exit(prev_state);
703 int process_fpemu_return(int sig, void __user *fault_addr)
705 if (sig == SIGSEGV || sig == SIGBUS) {
706 struct siginfo si = {0};
707 si.si_addr = fault_addr;
709 if (sig == SIGSEGV) {
710 down_read(¤t->mm->mmap_sem);
711 if (find_vma(current->mm, (unsigned long)fault_addr))
712 si.si_code = SEGV_ACCERR;
714 si.si_code = SEGV_MAPERR;
715 up_read(¤t->mm->mmap_sem);
717 si.si_code = BUS_ADRERR;
719 force_sig_info(sig, &si, current);
722 force_sig(sig, current);
729 static int simulate_fp(struct pt_regs *regs, unsigned int opcode,
730 unsigned long old_epc, unsigned long old_ra)
732 union mips_instruction inst = { .word = opcode };
733 void __user *fault_addr = NULL;
736 /* If it's obviously not an FP instruction, skip it */
737 switch (inst.i_format.opcode) {
751 * do_ri skipped over the instruction via compute_return_epc, undo
752 * that for the FPU emulator.
754 regs->cp0_epc = old_epc;
755 regs->regs[31] = old_ra;
757 /* Save the FP context to struct thread_struct */
760 /* Run the emulator */
761 sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
765 * We can't allow the emulated instruction to leave any of
766 * the cause bits set in $fcr31.
768 current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
770 /* If something went wrong, signal */
771 process_fpemu_return(sig, fault_addr);
773 /* Restore the hardware register state */
780 * XXX Delayed fp exceptions when doing a lazy ctx switch XXX
782 asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
784 enum ctx_state prev_state;
785 siginfo_t info = {0};
787 prev_state = exception_enter();
788 if (notify_die(DIE_FP, "FP exception", regs, 0, regs_to_trapnr(regs),
789 SIGFPE) == NOTIFY_STOP)
791 die_if_kernel("FP exception in kernel code", regs);
793 if (fcr31 & FPU_CSR_UNI_X) {
795 void __user *fault_addr = NULL;
798 * Unimplemented operation exception. If we've got the full
799 * software emulator on-board, let's use it...
801 * Force FPU to dump state into task/thread context. We're
802 * moving a lot of data here for what is probably a single
803 * instruction, but the alternative is to pre-decode the FP
804 * register operands before invoking the emulator, which seems
805 * a bit extreme for what should be an infrequent event.
807 /* Ensure 'resume' not overwrite saved fp context again. */
810 /* Run the emulator */
811 sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
815 * We can't allow the emulated instruction to leave any of
816 * the cause bits set in $fcr31.
818 current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
820 /* Restore the hardware register state */
821 own_fpu(1); /* Using the FPU again. */
823 /* If something went wrong, signal */
824 process_fpemu_return(sig, fault_addr);
830 * Inexact can happen together with Overflow or Underflow.
831 * Respect the mask to deliver the correct exception.
833 fcr31 &= (fcr31 & FPU_CSR_ALL_E) <<
834 (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E));
835 if (fcr31 & FPU_CSR_INV_X)
836 info.si_code = FPE_FLTINV;
837 else if (fcr31 & FPU_CSR_DIV_X)
838 info.si_code = FPE_FLTDIV;
839 else if (fcr31 & FPU_CSR_OVF_X)
840 info.si_code = FPE_FLTOVF;
841 else if (fcr31 & FPU_CSR_UDF_X)
842 info.si_code = FPE_FLTUND;
843 else if (fcr31 & FPU_CSR_INE_X)
844 info.si_code = FPE_FLTRES;
846 info.si_code = __SI_FAULT;
847 info.si_signo = SIGFPE;
849 info.si_addr = (void __user *) regs->cp0_epc;
850 force_sig_info(SIGFPE, &info, current);
853 exception_exit(prev_state);
856 void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
862 #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
863 if (kgdb_ll_trap(DIE_TRAP, str, regs, code, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
865 #endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
867 if (notify_die(DIE_TRAP, str, regs, code, regs_to_trapnr(regs),
868 SIGTRAP) == NOTIFY_STOP)
872 * A short test says that IRIX 5.3 sends SIGTRAP for all trap
873 * insns, even for trap and break codes that indicate arithmetic
874 * failures. Weird ...
875 * But should we continue the brokenness??? --macro
880 scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
881 die_if_kernel(b, regs);
882 if (code == BRK_DIVZERO)
883 info.si_code = FPE_INTDIV;
885 info.si_code = FPE_INTOVF;
886 info.si_signo = SIGFPE;
888 info.si_addr = (void __user *) regs->cp0_epc;
889 force_sig_info(SIGFPE, &info, current);
892 die_if_kernel("Kernel bug detected", regs);
893 force_sig(SIGTRAP, current);
897 * This breakpoint code is used by the FPU emulator to retake
898 * control of the CPU after executing the instruction from the
899 * delay slot of an emulated branch.
901 * Terminate if exception was recognized as a delay slot return
902 * otherwise handle as normal.
904 if (do_dsemulret(regs))
907 die_if_kernel("Math emu break/trap", regs);
908 force_sig(SIGTRAP, current);
911 scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
912 die_if_kernel(b, regs);
913 force_sig(SIGTRAP, current);
917 asmlinkage void do_bp(struct pt_regs *regs)
919 unsigned long epc = msk_isa16_mode(exception_epc(regs));
920 unsigned int opcode, bcode;
921 enum ctx_state prev_state;
925 if (!user_mode(regs))
928 prev_state = exception_enter();
929 if (get_isa16_mode(regs->cp0_epc)) {
932 if (__get_user(instr[0], (u16 __user *)epc))
935 if (!cpu_has_mmips) {
937 bcode = (instr[0] >> 5) & 0x3f;
938 } else if (mm_insn_16bit(instr[0])) {
939 /* 16-bit microMIPS BREAK */
940 bcode = instr[0] & 0xf;
942 /* 32-bit microMIPS BREAK */
943 if (__get_user(instr[1], (u16 __user *)(epc + 2)))
945 opcode = (instr[0] << 16) | instr[1];
946 bcode = (opcode >> 6) & ((1 << 20) - 1);
949 if (__get_user(opcode, (unsigned int __user *)epc))
951 bcode = (opcode >> 6) & ((1 << 20) - 1);
955 * There is the ancient bug in the MIPS assemblers that the break
956 * code starts left to bit 16 instead to bit 6 in the opcode.
957 * Gas is bug-compatible, but not always, grrr...
958 * We handle both cases with a simple heuristics. --macro
960 if (bcode >= (1 << 10))
961 bcode = ((bcode & ((1 << 10) - 1)) << 10) | (bcode >> 10);
964 * notify the kprobe handlers, if instruction is likely to
969 if (notify_die(DIE_BREAK, "debug", regs, bcode,
970 regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
974 case BRK_KPROBE_SSTEPBP:
975 if (notify_die(DIE_SSTEPBP, "single_step", regs, bcode,
976 regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
984 do_trap_or_bp(regs, bcode, "Break");
988 exception_exit(prev_state);
992 force_sig(SIGSEGV, current);
996 asmlinkage void do_tr(struct pt_regs *regs)
998 u32 opcode, tcode = 0;
999 enum ctx_state prev_state;
1002 unsigned long epc = msk_isa16_mode(exception_epc(regs));
1005 if (!user_mode(regs))
1008 prev_state = exception_enter();
1009 if (get_isa16_mode(regs->cp0_epc)) {
1010 if (__get_user(instr[0], (u16 __user *)(epc + 0)) ||
1011 __get_user(instr[1], (u16 __user *)(epc + 2)))
1013 opcode = (instr[0] << 16) | instr[1];
1014 /* Immediate versions don't provide a code. */
1015 if (!(opcode & OPCODE))
1016 tcode = (opcode >> 12) & ((1 << 4) - 1);
1018 if (__get_user(opcode, (u32 __user *)epc))
1020 /* Immediate versions don't provide a code. */
1021 if (!(opcode & OPCODE))
1022 tcode = (opcode >> 6) & ((1 << 10) - 1);
1025 do_trap_or_bp(regs, tcode, "Trap");
1029 exception_exit(prev_state);
1033 force_sig(SIGSEGV, current);
1037 asmlinkage void do_ri(struct pt_regs *regs)
1039 unsigned int __user *epc = (unsigned int __user *)exception_epc(regs);
1040 unsigned long old_epc = regs->cp0_epc;
1041 unsigned long old31 = regs->regs[31];
1042 enum ctx_state prev_state;
1043 unsigned int opcode = 0;
1047 * Avoid any kernel code. Just emulate the R2 instruction
1048 * as quickly as possible.
1050 if (mipsr2_emulation && cpu_has_mips_r6 &&
1051 likely(user_mode(regs)) &&
1052 likely(get_user(opcode, epc) >= 0)) {
1053 status = mipsr2_decoder(regs, opcode);
1057 task_thread_info(current)->r2_emul_return = 1;
1062 process_fpemu_return(status,
1063 ¤t->thread.cp0_baduaddr);
1064 task_thread_info(current)->r2_emul_return = 1;
1071 prev_state = exception_enter();
1073 if (notify_die(DIE_RI, "RI Fault", regs, 0, regs_to_trapnr(regs),
1074 SIGILL) == NOTIFY_STOP)
1077 die_if_kernel("Reserved instruction in kernel code", regs);
1079 if (unlikely(compute_return_epc(regs) < 0))
1082 if (get_isa16_mode(regs->cp0_epc)) {
1083 unsigned short mmop[2] = { 0 };
1085 if (unlikely(get_user(mmop[0], epc) < 0))
1087 if (unlikely(get_user(mmop[1], epc) < 0))
1089 opcode = (mmop[0] << 16) | mmop[1];
1092 status = simulate_rdhwr_mm(regs, opcode);
1094 if (unlikely(get_user(opcode, epc) < 0))
1097 if (!cpu_has_llsc && status < 0)
1098 status = simulate_llsc(regs, opcode);
1101 status = simulate_rdhwr_normal(regs, opcode);
1104 status = simulate_sync(regs, opcode);
1107 status = simulate_fp(regs, opcode, old_epc, old31);
1113 if (unlikely(status > 0)) {
1114 regs->cp0_epc = old_epc; /* Undo skip-over. */
1115 regs->regs[31] = old31;
1116 force_sig(status, current);
1120 exception_exit(prev_state);
1124 * MIPS MT processors may have fewer FPU contexts than CPU threads. If we've
1125 * emulated more than some threshold number of instructions, force migration to
1126 * a "CPU" that has FP support.
1128 static void mt_ase_fp_affinity(void)
1130 #ifdef CONFIG_MIPS_MT_FPAFF
1131 if (mt_fpemul_threshold > 0 &&
1132 ((current->thread.emulated_fp++ > mt_fpemul_threshold))) {
1134 * If there's no FPU present, or if the application has already
1135 * restricted the allowed set to exclude any CPUs with FPUs,
1136 * we'll skip the procedure.
1138 if (cpus_intersects(current->cpus_allowed, mt_fpu_cpumask)) {
1141 current->thread.user_cpus_allowed
1142 = current->cpus_allowed;
1143 cpus_and(tmask, current->cpus_allowed,
1145 set_cpus_allowed_ptr(current, &tmask);
1146 set_thread_flag(TIF_FPUBOUND);
1149 #endif /* CONFIG_MIPS_MT_FPAFF */
1153 * No lock; only written during early bootup by CPU 0.
1155 static RAW_NOTIFIER_HEAD(cu2_chain);
1157 int __ref register_cu2_notifier(struct notifier_block *nb)
1159 return raw_notifier_chain_register(&cu2_chain, nb);
1162 int cu2_notifier_call_chain(unsigned long val, void *v)
1164 return raw_notifier_call_chain(&cu2_chain, val, v);
1167 static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
1170 struct pt_regs *regs = data;
1172 die_if_kernel("COP2: Unhandled kernel unaligned access or invalid "
1173 "instruction", regs);
1174 force_sig(SIGILL, current);
1179 static int wait_on_fp_mode_switch(atomic_t *p)
1182 * The FP mode for this task is currently being switched. That may
1183 * involve modifications to the format of this tasks FP context which
1184 * make it unsafe to proceed with execution for the moment. Instead,
1185 * schedule some other task.
1191 static int enable_restore_fp_context(int msa)
1193 int err, was_fpu_owner, prior_msa;
1196 * If an FP mode switch is currently underway, wait for it to
1197 * complete before proceeding.
1199 wait_on_atomic_t(¤t->mm->context.fp_mode_switching,
1200 wait_on_fp_mode_switch, TASK_KILLABLE);
1203 /* First time FP context user. */
1209 set_thread_flag(TIF_USEDMSA);
1210 set_thread_flag(TIF_MSA_CTX_LIVE);
1219 * This task has formerly used the FP context.
1221 * If this thread has no live MSA vector context then we can simply
1222 * restore the scalar FP context. If it has live MSA vector context
1223 * (that is, it has or may have used MSA since last performing a
1224 * function call) then we'll need to restore the vector context. This
1225 * applies even if we're currently only executing a scalar FP
1226 * instruction. This is because if we were to later execute an MSA
1227 * instruction then we'd either have to:
1229 * - Restore the vector context & clobber any registers modified by
1230 * scalar FP instructions between now & then.
1234 * - Not restore the vector context & lose the most significant bits
1235 * of all vector registers.
1237 * Neither of those options is acceptable. We cannot restore the least
1238 * significant bits of the registers now & only restore the most
1239 * significant bits later because the most significant bits of any
1240 * vector registers whose aliased FP register is modified now will have
1241 * been zeroed. We'd have no way to know that when restoring the vector
1242 * context & thus may load an outdated value for the most significant
1243 * bits of a vector register.
1245 if (!msa && !thread_msa_context_live())
1249 * This task is using or has previously used MSA. Thus we require
1250 * that Status.FR == 1.
1253 was_fpu_owner = is_fpu_owner();
1254 err = own_fpu_inatomic(0);
1259 write_msa_csr(current->thread.fpu.msacsr);
1260 set_thread_flag(TIF_USEDMSA);
1263 * If this is the first time that the task is using MSA and it has
1264 * previously used scalar FP in this time slice then we already nave
1265 * FP context which we shouldn't clobber. We do however need to clear
1266 * the upper 64b of each vector register so that this task has no
1267 * opportunity to see data left behind by another.
1269 prior_msa = test_and_set_thread_flag(TIF_MSA_CTX_LIVE);
1270 if (!prior_msa && was_fpu_owner) {
1278 * Restore the least significant 64b of each vector register
1279 * from the existing scalar FP context.
1281 _restore_fp(current);
1284 * The task has not formerly used MSA, so clear the upper 64b
1285 * of each vector register such that it cannot see data left
1286 * behind by another task.
1290 /* We need to restore the vector context. */
1291 restore_msa(current);
1293 /* Restore the scalar FP control & status register */
1295 write_32bit_cp1_register(CP1_STATUS,
1296 current->thread.fpu.fcr31);
1305 asmlinkage void do_cpu(struct pt_regs *regs)
1307 enum ctx_state prev_state;
1308 unsigned int __user *epc;
1309 unsigned long old_epc, old31;
1310 unsigned int opcode;
1313 unsigned long __maybe_unused flags;
1315 prev_state = exception_enter();
1316 cpid = (regs->cp0_cause >> CAUSEB_CE) & 3;
1319 die_if_kernel("do_cpu invoked from kernel context!", regs);
1323 epc = (unsigned int __user *)exception_epc(regs);
1324 old_epc = regs->cp0_epc;
1325 old31 = regs->regs[31];
1329 if (unlikely(compute_return_epc(regs) < 0))
1332 if (get_isa16_mode(regs->cp0_epc)) {
1333 unsigned short mmop[2] = { 0 };
1335 if (unlikely(get_user(mmop[0], epc) < 0))
1337 if (unlikely(get_user(mmop[1], epc) < 0))
1339 opcode = (mmop[0] << 16) | mmop[1];
1342 status = simulate_rdhwr_mm(regs, opcode);
1344 if (unlikely(get_user(opcode, epc) < 0))
1347 if (!cpu_has_llsc && status < 0)
1348 status = simulate_llsc(regs, opcode);
1351 status = simulate_rdhwr_normal(regs, opcode);
1357 if (unlikely(status > 0)) {
1358 regs->cp0_epc = old_epc; /* Undo skip-over. */
1359 regs->regs[31] = old31;
1360 force_sig(status, current);
1367 * The COP3 opcode space and consequently the CP0.Status.CU3
1368 * bit and the CP0.Cause.CE=3 encoding have been removed as
1369 * of the MIPS III ISA. From the MIPS IV and MIPS32r2 ISAs
1370 * up the space has been reused for COP1X instructions, that
1371 * are enabled by the CP0.Status.CU1 bit and consequently
1372 * use the CP0.Cause.CE=1 encoding for Coprocessor Unusable
1373 * exceptions. Some FPU-less processors that implement one
1374 * of these ISAs however use this code erroneously for COP1X
1375 * instructions. Therefore we redirect this trap to the FP
1378 if (raw_cpu_has_fpu || !cpu_has_mips_4_5_64_r2_r6) {
1379 force_sig(SIGILL, current);
1385 err = enable_restore_fp_context(0);
1387 if (!raw_cpu_has_fpu || err) {
1389 void __user *fault_addr = NULL;
1390 sig = fpu_emulator_cop1Handler(regs,
1391 ¤t->thread.fpu,
1395 * We can't allow the emulated instruction to leave
1396 * any of the cause bits set in $fcr31.
1398 current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
1400 if (!process_fpemu_return(sig, fault_addr) && !err)
1401 mt_ase_fp_affinity();
1407 raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs);
1411 exception_exit(prev_state);
1414 asmlinkage void do_msa_fpe(struct pt_regs *regs)
1416 enum ctx_state prev_state;
1418 prev_state = exception_enter();
1419 die_if_kernel("do_msa_fpe invoked from kernel context!", regs);
1420 force_sig(SIGFPE, current);
1421 exception_exit(prev_state);
1424 asmlinkage void do_msa(struct pt_regs *regs)
1426 enum ctx_state prev_state;
1429 prev_state = exception_enter();
1431 if (!cpu_has_msa || test_thread_flag(TIF_32BIT_FPREGS)) {
1432 force_sig(SIGILL, current);
1436 die_if_kernel("do_msa invoked from kernel context!", regs);
1438 err = enable_restore_fp_context(1);
1440 force_sig(SIGILL, current);
1442 exception_exit(prev_state);
1445 asmlinkage void do_mdmx(struct pt_regs *regs)
1447 enum ctx_state prev_state;
1449 prev_state = exception_enter();
1450 force_sig(SIGILL, current);
1451 exception_exit(prev_state);
1455 * Called with interrupts disabled.
1457 asmlinkage void do_watch(struct pt_regs *regs)
1459 enum ctx_state prev_state;
1462 prev_state = exception_enter();
1464 * Clear WP (bit 22) bit of cause register so we don't loop
1467 cause = read_c0_cause();
1468 cause &= ~(1 << 22);
1469 write_c0_cause(cause);
1472 * If the current thread has the watch registers loaded, save
1473 * their values and send SIGTRAP. Otherwise another thread
1474 * left the registers set, clear them and continue.
1476 if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) {
1477 mips_read_watch_registers();
1479 force_sig(SIGTRAP, current);
1481 mips_clear_watch_registers();
1484 exception_exit(prev_state);
1487 asmlinkage void do_mcheck(struct pt_regs *regs)
1489 const int field = 2 * sizeof(unsigned long);
1490 int multi_match = regs->cp0_status & ST0_TS;
1491 enum ctx_state prev_state;
1493 prev_state = exception_enter();
1497 pr_err("Index : %0x\n", read_c0_index());
1498 pr_err("Pagemask: %0x\n", read_c0_pagemask());
1499 pr_err("EntryHi : %0*lx\n", field, read_c0_entryhi());
1500 pr_err("EntryLo0: %0*lx\n", field, read_c0_entrylo0());
1501 pr_err("EntryLo1: %0*lx\n", field, read_c0_entrylo1());
1502 pr_err("Wired : %0x\n", read_c0_wired());
1503 pr_err("Pagegrain: %0x\n", read_c0_pagegrain());
1505 pr_err("PWField : %0*lx\n", field, read_c0_pwfield());
1506 pr_err("PWSize : %0*lx\n", field, read_c0_pwsize());
1507 pr_err("PWCtl : %0x\n", read_c0_pwctl());
1513 show_code((unsigned int __user *) regs->cp0_epc);
1516 * Some chips may have other causes of machine check (e.g. SB1
1519 panic("Caught Machine Check exception - %scaused by multiple "
1520 "matching entries in the TLB.",
1521 (multi_match) ? "" : "not ");
1524 asmlinkage void do_mt(struct pt_regs *regs)
1528 subcode = (read_vpe_c0_vpecontrol() & VPECONTROL_EXCPT)
1529 >> VPECONTROL_EXCPT_SHIFT;
1532 printk(KERN_DEBUG "Thread Underflow\n");
1535 printk(KERN_DEBUG "Thread Overflow\n");
1538 printk(KERN_DEBUG "Invalid YIELD Qualifier\n");
1541 printk(KERN_DEBUG "Gating Storage Exception\n");
1544 printk(KERN_DEBUG "YIELD Scheduler Exception\n");
1547 printk(KERN_DEBUG "Gating Storage Scheduler Exception\n");
1550 printk(KERN_DEBUG "*** UNKNOWN THREAD EXCEPTION %d ***\n",
1554 die_if_kernel("MIPS MT Thread exception in kernel", regs);
1556 force_sig(SIGILL, current);
1560 asmlinkage void do_dsp(struct pt_regs *regs)
1563 panic("Unexpected DSP exception");
1565 force_sig(SIGILL, current);
1568 asmlinkage void do_reserved(struct pt_regs *regs)
1571 * Game over - no way to handle this if it ever occurs. Most probably
1572 * caused by a new unknown cpu type or after another deadly
1573 * hard/software error.
1576 panic("Caught reserved exception %ld - should not happen.",
1577 (regs->cp0_cause & 0x7f) >> 2);
1580 static int __initdata l1parity = 1;
1581 static int __init nol1parity(char *s)
1586 __setup("nol1par", nol1parity);
1587 static int __initdata l2parity = 1;
1588 static int __init nol2parity(char *s)
1593 __setup("nol2par", nol2parity);
1596 * Some MIPS CPUs can enable/disable for cache parity detection, but do
1597 * it different ways.
1599 static inline void parity_protection_init(void)
1601 switch (current_cpu_type()) {
1607 case CPU_INTERAPTIV:
1610 case CPU_QEMU_GENERIC:
1612 #define ERRCTL_PE 0x80000000
1613 #define ERRCTL_L2P 0x00800000
1614 unsigned long errctl;
1615 unsigned int l1parity_present, l2parity_present;
1617 errctl = read_c0_ecc();
1618 errctl &= ~(ERRCTL_PE|ERRCTL_L2P);
1620 /* probe L1 parity support */
1621 write_c0_ecc(errctl | ERRCTL_PE);
1622 back_to_back_c0_hazard();
1623 l1parity_present = (read_c0_ecc() & ERRCTL_PE);
1625 /* probe L2 parity support */
1626 write_c0_ecc(errctl|ERRCTL_L2P);
1627 back_to_back_c0_hazard();
1628 l2parity_present = (read_c0_ecc() & ERRCTL_L2P);
1630 if (l1parity_present && l2parity_present) {
1632 errctl |= ERRCTL_PE;
1633 if (l1parity ^ l2parity)
1634 errctl |= ERRCTL_L2P;
1635 } else if (l1parity_present) {
1637 errctl |= ERRCTL_PE;
1638 } else if (l2parity_present) {
1640 errctl |= ERRCTL_L2P;
1642 /* No parity available */
1645 printk(KERN_INFO "Writing ErrCtl register=%08lx\n", errctl);
1647 write_c0_ecc(errctl);
1648 back_to_back_c0_hazard();
1649 errctl = read_c0_ecc();
1650 printk(KERN_INFO "Readback ErrCtl register=%08lx\n", errctl);
1652 if (l1parity_present)
1653 printk(KERN_INFO "Cache parity protection %sabled\n",
1654 (errctl & ERRCTL_PE) ? "en" : "dis");
1656 if (l2parity_present) {
1657 if (l1parity_present && l1parity)
1658 errctl ^= ERRCTL_L2P;
1659 printk(KERN_INFO "L2 cache parity protection %sabled\n",
1660 (errctl & ERRCTL_L2P) ? "en" : "dis");
1668 write_c0_ecc(0x80000000);
1669 back_to_back_c0_hazard();
1670 /* Set the PE bit (bit 31) in the c0_errctl register. */
1671 printk(KERN_INFO "Cache parity protection %sabled\n",
1672 (read_c0_ecc() & 0x80000000) ? "en" : "dis");
1676 /* Clear the DE bit (bit 16) in the c0_status register. */
1677 printk(KERN_INFO "Enable cache parity protection for "
1678 "MIPS 20KC/25KF CPUs.\n");
1679 clear_c0_status(ST0_DE);
1686 asmlinkage void cache_parity_error(void)
1688 const int field = 2 * sizeof(unsigned long);
1689 unsigned int reg_val;
1691 /* For the moment, report the problem and hang. */
1692 printk("Cache error exception:\n");
1693 printk("cp0_errorepc == %0*lx\n", field, read_c0_errorepc());
1694 reg_val = read_c0_cacheerr();
1695 printk("c0_cacheerr == %08x\n", reg_val);
1697 printk("Decoded c0_cacheerr: %s cache fault in %s reference.\n",
1698 reg_val & (1<<30) ? "secondary" : "primary",
1699 reg_val & (1<<31) ? "data" : "insn");
1700 if ((cpu_has_mips_r2_r6) &&
1701 ((current_cpu_data.processor_id & 0xff0000) == PRID_COMP_MIPS)) {
1702 pr_err("Error bits: %s%s%s%s%s%s%s%s\n",
1703 reg_val & (1<<29) ? "ED " : "",
1704 reg_val & (1<<28) ? "ET " : "",
1705 reg_val & (1<<27) ? "ES " : "",
1706 reg_val & (1<<26) ? "EE " : "",
1707 reg_val & (1<<25) ? "EB " : "",
1708 reg_val & (1<<24) ? "EI " : "",
1709 reg_val & (1<<23) ? "E1 " : "",
1710 reg_val & (1<<22) ? "E0 " : "");
1712 pr_err("Error bits: %s%s%s%s%s%s%s\n",
1713 reg_val & (1<<29) ? "ED " : "",
1714 reg_val & (1<<28) ? "ET " : "",
1715 reg_val & (1<<26) ? "EE " : "",
1716 reg_val & (1<<25) ? "EB " : "",
1717 reg_val & (1<<24) ? "EI " : "",
1718 reg_val & (1<<23) ? "E1 " : "",
1719 reg_val & (1<<22) ? "E0 " : "");
1721 printk("IDX: 0x%08x\n", reg_val & ((1<<22)-1));
1723 #if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
1724 if (reg_val & (1<<22))
1725 printk("DErrAddr0: 0x%0*lx\n", field, read_c0_derraddr0());
1727 if (reg_val & (1<<23))
1728 printk("DErrAddr1: 0x%0*lx\n", field, read_c0_derraddr1());
1731 panic("Can't handle the cache error!");
1734 asmlinkage void do_ftlb(void)
1736 const int field = 2 * sizeof(unsigned long);
1737 unsigned int reg_val;
1739 /* For the moment, report the problem and hang. */
1740 if ((cpu_has_mips_r2_r6) &&
1741 ((current_cpu_data.processor_id & 0xff0000) == PRID_COMP_MIPS)) {
1742 pr_err("FTLB error exception, cp0_ecc=0x%08x:\n",
1744 pr_err("cp0_errorepc == %0*lx\n", field, read_c0_errorepc());
1745 reg_val = read_c0_cacheerr();
1746 pr_err("c0_cacheerr == %08x\n", reg_val);
1748 if ((reg_val & 0xc0000000) == 0xc0000000) {
1749 pr_err("Decoded c0_cacheerr: FTLB parity error\n");
1751 pr_err("Decoded c0_cacheerr: %s cache fault in %s reference.\n",
1752 reg_val & (1<<30) ? "secondary" : "primary",
1753 reg_val & (1<<31) ? "data" : "insn");
1756 pr_err("FTLB error exception\n");
1758 /* Just print the cacheerr bits for now */
1759 cache_parity_error();
1763 * SDBBP EJTAG debug exception handler.
1764 * We skip the instruction and return to the next instruction.
1766 void ejtag_exception_handler(struct pt_regs *regs)
1768 const int field = 2 * sizeof(unsigned long);
1769 unsigned long depc, old_epc, old_ra;
1772 printk(KERN_DEBUG "SDBBP EJTAG debug exception - not handled yet, just ignored!\n");
1773 depc = read_c0_depc();
1774 debug = read_c0_debug();
1775 printk(KERN_DEBUG "c0_depc = %0*lx, DEBUG = %08x\n", field, depc, debug);
1776 if (debug & 0x80000000) {
1778 * In branch delay slot.
1779 * We cheat a little bit here and use EPC to calculate the
1780 * debug return address (DEPC). EPC is restored after the
1783 old_epc = regs->cp0_epc;
1784 old_ra = regs->regs[31];
1785 regs->cp0_epc = depc;
1786 compute_return_epc(regs);
1787 depc = regs->cp0_epc;
1788 regs->cp0_epc = old_epc;
1789 regs->regs[31] = old_ra;
1792 write_c0_depc(depc);
1795 printk(KERN_DEBUG "\n\n----- Enable EJTAG single stepping ----\n\n");
1796 write_c0_debug(debug | 0x100);
1801 * NMI exception handler.
1802 * No lock; only written during early bootup by CPU 0.
1804 static RAW_NOTIFIER_HEAD(nmi_chain);
1806 int register_nmi_notifier(struct notifier_block *nb)
1808 return raw_notifier_chain_register(&nmi_chain, nb);
1811 void __noreturn nmi_exception_handler(struct pt_regs *regs)
1815 raw_notifier_call_chain(&nmi_chain, 0, regs);
1817 snprintf(str, 100, "CPU%d NMI taken, CP0_EPC=%lx\n",
1818 smp_processor_id(), regs->cp0_epc);
1819 regs->cp0_epc = read_c0_errorepc();
1823 #define VECTORSPACING 0x100 /* for EI/VI mode */
1825 unsigned long ebase;
1826 unsigned long exception_handlers[32];
1827 unsigned long vi_handlers[64];
1829 void __init *set_except_vector(int n, void *addr)
1831 unsigned long handler = (unsigned long) addr;
1832 unsigned long old_handler;
1834 #ifdef CONFIG_CPU_MICROMIPS
1836 * Only the TLB handlers are cache aligned with an even
1837 * address. All other handlers are on an odd address and
1838 * require no modification. Otherwise, MIPS32 mode will
1839 * be entered when handling any TLB exceptions. That
1840 * would be bad...since we must stay in microMIPS mode.
1842 if (!(handler & 0x1))
1845 old_handler = xchg(&exception_handlers[n], handler);
1847 if (n == 0 && cpu_has_divec) {
1848 #ifdef CONFIG_CPU_MICROMIPS
1849 unsigned long jump_mask = ~((1 << 27) - 1);
1851 unsigned long jump_mask = ~((1 << 28) - 1);
1853 u32 *buf = (u32 *)(ebase + 0x200);
1854 unsigned int k0 = 26;
1855 if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) {
1856 uasm_i_j(&buf, handler & ~jump_mask);
1859 UASM_i_LA(&buf, k0, handler);
1860 uasm_i_jr(&buf, k0);
1863 local_flush_icache_range(ebase + 0x200, (unsigned long)buf);
1865 return (void *)old_handler;
1868 static void do_default_vi(void)
1870 show_regs(get_irq_regs());
1871 panic("Caught unexpected vectored interrupt.");
1874 static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
1876 unsigned long handler;
1877 unsigned long old_handler = vi_handlers[n];
1878 int srssets = current_cpu_data.srsets;
1882 BUG_ON(!cpu_has_veic && !cpu_has_vint);
1885 handler = (unsigned long) do_default_vi;
1888 handler = (unsigned long) addr;
1889 vi_handlers[n] = handler;
1891 b = (unsigned char *)(ebase + 0x200 + n*VECTORSPACING);
1894 panic("Shadow register set %d not supported", srs);
1897 if (board_bind_eic_interrupt)
1898 board_bind_eic_interrupt(n, srs);
1899 } else if (cpu_has_vint) {
1900 /* SRSMap is only defined if shadow sets are implemented */
1902 change_c0_srsmap(0xf << n*4, srs << n*4);
1907 * If no shadow set is selected then use the default handler
1908 * that does normal register saving and standard interrupt exit
1910 extern char except_vec_vi, except_vec_vi_lui;
1911 extern char except_vec_vi_ori, except_vec_vi_end;
1912 extern char rollback_except_vec_vi;
1913 char *vec_start = using_rollback_handler() ?
1914 &rollback_except_vec_vi : &except_vec_vi;
1915 #if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN)
1916 const int lui_offset = &except_vec_vi_lui - vec_start + 2;
1917 const int ori_offset = &except_vec_vi_ori - vec_start + 2;
1919 const int lui_offset = &except_vec_vi_lui - vec_start;
1920 const int ori_offset = &except_vec_vi_ori - vec_start;
1922 const int handler_len = &except_vec_vi_end - vec_start;
1924 if (handler_len > VECTORSPACING) {
1926 * Sigh... panicing won't help as the console
1927 * is probably not configured :(
1929 panic("VECTORSPACING too small");
1932 set_handler(((unsigned long)b - ebase), vec_start,
1933 #ifdef CONFIG_CPU_MICROMIPS
1938 h = (u16 *)(b + lui_offset);
1939 *h = (handler >> 16) & 0xffff;
1940 h = (u16 *)(b + ori_offset);
1941 *h = (handler & 0xffff);
1942 local_flush_icache_range((unsigned long)b,
1943 (unsigned long)(b+handler_len));
1947 * In other cases jump directly to the interrupt handler. It
1948 * is the handler's responsibility to save registers if required
1949 * (eg hi/lo) and return from the exception using "eret".
1955 #ifdef CONFIG_CPU_MICROMIPS
1956 insn = 0xd4000000 | (((u32)handler & 0x07ffffff) >> 1);
1958 insn = 0x08000000 | (((u32)handler & 0x0fffffff) >> 2);
1960 h[0] = (insn >> 16) & 0xffff;
1961 h[1] = insn & 0xffff;
1964 local_flush_icache_range((unsigned long)b,
1965 (unsigned long)(b+8));
1968 return (void *)old_handler;
1971 void *set_vi_handler(int n, vi_handler_t addr)
1973 return set_vi_srs_handler(n, addr, 0);
1976 extern void tlb_init(void);
1981 int cp0_compare_irq;
1982 EXPORT_SYMBOL_GPL(cp0_compare_irq);
1983 int cp0_compare_irq_shift;
1986 * Performance counter IRQ or -1 if shared with timer
1988 int cp0_perfcount_irq;
1989 EXPORT_SYMBOL_GPL(cp0_perfcount_irq);
1992 * Fast debug channel IRQ or -1 if not present
1995 EXPORT_SYMBOL_GPL(cp0_fdc_irq);
1999 static int __init ulri_disable(char *s)
2001 pr_info("Disabling ulri\n");
2006 __setup("noulri", ulri_disable);
2008 /* configure STATUS register */
2009 static void configure_status(void)
2012 * Disable coprocessors and select 32-bit or 64-bit addressing
2013 * and the 16/32 or 32/32 FPR register model. Reset the BEV
2014 * flag that some firmware may have left set and the TS bit (for
2015 * IP27). Set XX for ISA IV code to work.
2017 unsigned int status_set = ST0_CU0;
2019 status_set |= ST0_FR|ST0_KX|ST0_SX|ST0_UX;
2021 if (current_cpu_data.isa_level & MIPS_CPU_ISA_IV)
2022 status_set |= ST0_XX;
2024 status_set |= ST0_MX;
2026 change_c0_status(ST0_CU|ST0_MX|ST0_RE|ST0_FR|ST0_BEV|ST0_TS|ST0_KX|ST0_SX|ST0_UX,
2030 /* configure HWRENA register */
2031 static void configure_hwrena(void)
2033 unsigned int hwrena = cpu_hwrena_impl_bits;
2035 if (cpu_has_mips_r2_r6)
2036 hwrena |= 0x0000000f;
2038 if (!noulri && cpu_has_userlocal)
2039 hwrena |= (1 << 29);
2042 write_c0_hwrena(hwrena);
2045 static void configure_exception_vector(void)
2047 if (cpu_has_veic || cpu_has_vint) {
2048 unsigned long sr = set_c0_status(ST0_BEV);
2049 write_c0_ebase(ebase);
2050 write_c0_status(sr);
2051 /* Setting vector spacing enables EI/VI mode */
2052 change_c0_intctl(0x3e0, VECTORSPACING);
2054 if (cpu_has_divec) {
2055 if (cpu_has_mipsmt) {
2056 unsigned int vpflags = dvpe();
2057 set_c0_cause(CAUSEF_IV);
2060 set_c0_cause(CAUSEF_IV);
2064 void per_cpu_trap_init(bool is_boot_cpu)
2066 unsigned int cpu = smp_processor_id();
2071 configure_exception_vector();
2074 * Before R2 both interrupt numbers were fixed to 7, so on R2 only:
2076 * o read IntCtl.IPTI to determine the timer interrupt
2077 * o read IntCtl.IPPCI to determine the performance counter interrupt
2078 * o read IntCtl.IPFDC to determine the fast debug channel interrupt
2080 if (cpu_has_mips_r2_r6) {
2081 cp0_compare_irq_shift = CAUSEB_TI - CAUSEB_IP;
2082 cp0_compare_irq = (read_c0_intctl() >> INTCTLB_IPTI) & 7;
2083 cp0_perfcount_irq = (read_c0_intctl() >> INTCTLB_IPPCI) & 7;
2084 cp0_fdc_irq = (read_c0_intctl() >> INTCTLB_IPFDC) & 7;
2089 cp0_compare_irq = CP0_LEGACY_COMPARE_IRQ;
2090 cp0_compare_irq_shift = CP0_LEGACY_PERFCNT_IRQ;
2091 cp0_perfcount_irq = -1;
2095 if (!cpu_data[cpu].asid_cache)
2096 cpu_data[cpu].asid_cache = ASID_FIRST_VERSION;
2098 atomic_inc(&init_mm.mm_count);
2099 current->active_mm = &init_mm;
2100 BUG_ON(current->mm);
2101 enter_lazy_tlb(&init_mm, current);
2103 /* Boot CPU's cache setup in setup_arch(). */
2107 TLBMISS_HANDLER_SETUP();
2110 /* Install CPU exception handler */
2111 void set_handler(unsigned long offset, void *addr, unsigned long size)
2113 #ifdef CONFIG_CPU_MICROMIPS
2114 memcpy((void *)(ebase + offset), ((unsigned char *)addr - 1), size);
2116 memcpy((void *)(ebase + offset), addr, size);
2118 local_flush_icache_range(ebase + offset, ebase + offset + size);
2121 static char panic_null_cerr[] =
2122 "Trying to set NULL cache error exception handler";
2125 * Install uncached CPU exception handler.
2126 * This is suitable only for the cache error exception which is the only
2127 * exception handler that is being run uncached.
2129 void set_uncached_handler(unsigned long offset, void *addr,
2132 unsigned long uncached_ebase = CKSEG1ADDR(ebase);
2135 panic(panic_null_cerr);
2137 memcpy((void *)(uncached_ebase + offset), addr, size);
2140 static int __initdata rdhwr_noopt;
2141 static int __init set_rdhwr_noopt(char *str)
2147 __setup("rdhwr_noopt", set_rdhwr_noopt);
2149 void __init trap_init(void)
2151 extern char except_vec3_generic;
2152 extern char except_vec4;
2153 extern char except_vec3_r4000;
2158 #if defined(CONFIG_KGDB)
2159 if (kgdb_early_setup)
2160 return; /* Already done */
2163 if (cpu_has_veic || cpu_has_vint) {
2164 unsigned long size = 0x200 + VECTORSPACING*64;
2165 ebase = (unsigned long)
2166 __alloc_bootmem(size, 1 << fls(size), 0);
2168 #ifdef CONFIG_KVM_GUEST
2169 #define KVM_GUEST_KSEG0 0x40000000
2170 ebase = KVM_GUEST_KSEG0;
2174 if (cpu_has_mips_r2_r6)
2175 ebase += (read_c0_ebase() & 0x3ffff000);
2178 if (cpu_has_mmips) {
2179 unsigned int config3 = read_c0_config3();
2181 if (IS_ENABLED(CONFIG_CPU_MICROMIPS))
2182 write_c0_config3(config3 | MIPS_CONF3_ISA_OE);
2184 write_c0_config3(config3 & ~MIPS_CONF3_ISA_OE);
2187 if (board_ebase_setup)
2188 board_ebase_setup();
2189 per_cpu_trap_init(true);
2192 * Copy the generic exception handlers to their final destination.
2193 * This will be overriden later as suitable for a particular
2196 set_handler(0x180, &except_vec3_generic, 0x80);
2199 * Setup default vectors
2201 for (i = 0; i <= 31; i++)
2202 set_except_vector(i, handle_reserved);
2205 * Copy the EJTAG debug exception vector handler code to it's final
2208 if (cpu_has_ejtag && board_ejtag_handler_setup)
2209 board_ejtag_handler_setup();
2212 * Only some CPUs have the watch exceptions.
2215 set_except_vector(23, handle_watch);
2218 * Initialise interrupt handlers
2220 if (cpu_has_veic || cpu_has_vint) {
2221 int nvec = cpu_has_veic ? 64 : 8;
2222 for (i = 0; i < nvec; i++)
2223 set_vi_handler(i, NULL);
2225 else if (cpu_has_divec)
2226 set_handler(0x200, &except_vec4, 0x8);
2229 * Some CPUs can enable/disable for cache parity detection, but does
2230 * it different ways.
2232 parity_protection_init();
2235 * The Data Bus Errors / Instruction Bus Errors are signaled
2236 * by external hardware. Therefore these two exceptions
2237 * may have board specific handlers.
2242 set_except_vector(0, using_rollback_handler() ? rollback_handle_int
2244 set_except_vector(1, handle_tlbm);
2245 set_except_vector(2, handle_tlbl);
2246 set_except_vector(3, handle_tlbs);
2248 set_except_vector(4, handle_adel);
2249 set_except_vector(5, handle_ades);
2251 set_except_vector(6, handle_ibe);
2252 set_except_vector(7, handle_dbe);
2254 set_except_vector(8, handle_sys);
2255 set_except_vector(9, handle_bp);
2256 set_except_vector(10, rdhwr_noopt ? handle_ri :
2257 (cpu_has_vtag_icache ?
2258 handle_ri_rdhwr_vivt : handle_ri_rdhwr));
2259 set_except_vector(11, handle_cpu);
2260 set_except_vector(12, handle_ov);
2261 set_except_vector(13, handle_tr);
2262 set_except_vector(14, handle_msa_fpe);
2264 if (current_cpu_type() == CPU_R6000 ||
2265 current_cpu_type() == CPU_R6000A) {
2267 * The R6000 is the only R-series CPU that features a machine
2268 * check exception (similar to the R4000 cache error) and
2269 * unaligned ldc1/sdc1 exception. The handlers have not been
2270 * written yet. Well, anyway there is no R6000 machine on the
2271 * current list of targets for Linux/MIPS.
2272 * (Duh, crap, there is someone with a triple R6k machine)
2274 //set_except_vector(14, handle_mc);
2275 //set_except_vector(15, handle_ndc);
2279 if (board_nmi_handler_setup)
2280 board_nmi_handler_setup();
2282 if (cpu_has_fpu && !cpu_has_nofpuex)
2283 set_except_vector(15, handle_fpe);
2285 set_except_vector(16, handle_ftlb);
2287 if (cpu_has_rixiex) {
2288 set_except_vector(19, tlb_do_page_fault_0);
2289 set_except_vector(20, tlb_do_page_fault_0);
2292 set_except_vector(21, handle_msa);
2293 set_except_vector(22, handle_mdmx);
2296 set_except_vector(24, handle_mcheck);
2299 set_except_vector(25, handle_mt);
2301 set_except_vector(26, handle_dsp);
2303 if (board_cache_error_setup)
2304 board_cache_error_setup();
2307 /* Special exception: R4[04]00 uses also the divec space. */
2308 set_handler(0x180, &except_vec3_r4000, 0x100);
2309 else if (cpu_has_4kex)
2310 set_handler(0x180, &except_vec3_generic, 0x80);
2312 set_handler(0x080, &except_vec3_generic, 0x80);
2314 local_flush_icache_range(ebase, ebase + 0x400);
2316 sort_extable(__start___dbe_table, __stop___dbe_table);
2318 cu2_notifier(default_cu2_call, 0x80000000); /* Run last */
2321 static int trap_pm_notifier(struct notifier_block *self, unsigned long cmd,
2325 case CPU_PM_ENTER_FAILED:
2329 configure_exception_vector();
2331 /* Restore register with CPU number for TLB handlers */
2332 TLBMISS_HANDLER_RESTORE();
2340 static struct notifier_block trap_pm_notifier_block = {
2341 .notifier_call = trap_pm_notifier,
2344 static int __init trap_pm_init(void)
2346 return cpu_pm_register_notifier(&trap_pm_notifier_block);
2348 arch_initcall(trap_pm_init);