2 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
4 * kernel entry points (interruptions, system call wrappers)
5 * Copyright (C) 1999,2000 Philipp Rumpf
6 * Copyright (C) 1999 SuSE GmbH Nuernberg
7 * Copyright (C) 2000 Hewlett-Packard (John Marvin)
8 * Copyright (C) 1999 Hewlett-Packard (Frank Rowand)
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 #include <asm/asm-offsets.h>
27 /* we have the following possibilities to act on an interruption:
28 * - handle in assembly and use shadowed registers only
29 * - save registers to kernel stack and handle in assembly or C */
33 #include <asm/cache.h> /* for L1_CACHE_SHIFT */
34 #include <asm/assembly.h> /* for LDREG/STREG defines */
35 #include <asm/pgtable.h>
36 #include <asm/signal.h>
37 #include <asm/unistd.h>
38 #include <asm/thread_info.h>
40 #include <linux/linkage.h>
48 .import pa_dbit_lock,data
50 /* space_to_prot macro creates a prot id from a space id */
52 #if (SPACEID_SHIFT) == 0
53 .macro space_to_prot spc prot
54 depd,z \spc,62,31,\prot
57 .macro space_to_prot spc prot
58 extrd,u \spc,(64 - (SPACEID_SHIFT)),32,\prot
62 /* Switch to virtual mapping, trashing only %r1 */
65 rsm PSW_SM_I, %r0 /* barrier for "Relied upon Translation */
69 or,= %r0,%r1,%r0 /* Only save sr7 in sr3 if sr7 != 0 */
72 load32 KERNEL_PSW, %r1
74 rsm PSW_SM_QUIET,%r0 /* second "heavy weight" ctl op */
77 mtctl %r0, %cr17 /* Clear IIASQ tail */
78 mtctl %r0, %cr17 /* Clear IIASQ head */
81 mtctl %r1, %cr18 /* Set IIAOQ tail */
83 mtctl %r1, %cr18 /* Set IIAOQ head */
90 * The "get_stack" macros are responsible for determining the
94 * Already using a kernel stack, so call the
95 * get_stack_use_r30 macro to push a pt_regs structure
96 * on the stack, and store registers there.
98 * Need to set up a kernel stack, so call the
99 * get_stack_use_cr30 macro to set up a pointer
100 * to the pt_regs structure contained within the
101 * task pointer pointed to by cr30. Set the stack
102 * pointer to point to the end of the task structure.
104 * Note that we use shadowed registers for temps until
105 * we can save %r26 and %r29. %r26 is used to preserve
106 * %r8 (a shadowed register) which temporarily contained
107 * either the fault type ("code") or the eirr. We need
108 * to use a non-shadowed register to carry the value over
109 * the rfir in virt_map. We use %r26 since this value winds
110 * up being passed as the argument to either do_cpu_irq_mask
111 * or handle_interruption. %r29 is used to hold a pointer
112 * the register save area, and once again, it needs to
113 * be a non-shadowed register so that it survives the rfir.
115 * N.B. TASK_SZ_ALGN and PT_SZ_ALGN include space for a stack frame.
118 .macro get_stack_use_cr30
120 /* we save the registers in the task struct */
124 LDREG TI_TASK(%r9), %r1 /* thread_info -> task_struct */
126 ldo TASK_REGS(%r9),%r9
127 STREG %r30, PT_GR30(%r9)
128 STREG %r29,PT_GR29(%r9)
129 STREG %r26,PT_GR26(%r9)
132 ldo THREAD_SZ_ALGN(%r1), %r30
135 .macro get_stack_use_r30
137 /* we put a struct pt_regs on the stack and save the registers there */
140 STREG %r30,PT_GR30(%r9)
141 ldo PT_SZ_ALGN(%r30),%r30
142 STREG %r29,PT_GR29(%r9)
143 STREG %r26,PT_GR26(%r9)
148 LDREG PT_GR1(%r29), %r1
149 LDREG PT_GR30(%r29),%r30
150 LDREG PT_GR29(%r29),%r29
153 /* default interruption handler
154 * (calls traps.c:handle_interruption) */
161 /* Interrupt interruption handler
162 * (calls irq.c:do_cpu_irq_mask) */
169 .import os_hpmc, code
173 nop /* must be a NOP, will be patched later */
174 load32 PA(os_hpmc), %r3
177 .word 0 /* checksum (will be patched) */
178 .word PA(os_hpmc) /* address of handler */
179 .word 0 /* length of handler */
183 * Performance Note: Instructions will be moved up into
184 * this part of the code later on, once we are sure
185 * that the tlb miss handlers are close to final form.
188 /* Register definitions for tlb miss handler macros */
190 va = r8 /* virtual address for which the trap occured */
191 spc = r24 /* space for which the trap occured */
196 * itlb miss interruption handler (parisc 1.1 - 32 bit)
210 * itlb miss interruption handler (parisc 2.0)
227 * naitlb miss interruption handler (parisc 1.1 - 32 bit)
230 .macro naitlb_11 code
241 * naitlb miss interruption handler (parisc 2.0)
244 .macro naitlb_20 code
259 * dtlb miss interruption handler (parisc 1.1 - 32 bit)
273 * dtlb miss interruption handler (parisc 2.0)
290 /* nadtlb miss interruption handler (parisc 1.1 - 32 bit) */
292 .macro nadtlb_11 code
302 /* nadtlb miss interruption handler (parisc 2.0) */
304 .macro nadtlb_20 code
319 * dirty bit trap interruption handler (parisc 1.1 - 32 bit)
333 * dirty bit trap interruption handler (parisc 2.0)
349 /* In LP64, the space contains part of the upper 32 bits of the
350 * fault. We have to extract this and place it in the va,
351 * zeroing the corresponding bits in the space register */
352 .macro space_adjust spc,va,tmp
354 extrd,u \spc,63,SPACEID_SHIFT,\tmp
355 depd %r0,63,SPACEID_SHIFT,\spc
356 depd \tmp,31,SPACEID_SHIFT,\va
360 .import swapper_pg_dir,code
362 /* Get the pgd. For faults on space zero (kernel space), this
363 * is simply swapper_pg_dir. For user space faults, the
364 * pgd is stored in %cr25 */
365 .macro get_pgd spc,reg
366 ldil L%PA(swapper_pg_dir),\reg
367 ldo R%PA(swapper_pg_dir)(\reg),\reg
368 or,COND(=) %r0,\spc,%r0
373 space_check(spc,tmp,fault)
375 spc - The space we saw the fault with.
376 tmp - The place to store the current space.
377 fault - Function to call on failure.
379 Only allow faults on different spaces from the
380 currently active one if we're the kernel
383 .macro space_check spc,tmp,fault
385 or,COND(<>) %r0,\spc,%r0 /* user may execute gateway page
386 * as kernel, so defeat the space
389 or,COND(=) %r0,\tmp,%r0 /* nullify if executing as kernel */
390 cmpb,COND(<>),n \tmp,\spc,\fault
393 /* Look up a PTE in a 2-Level scheme (faulting at each
394 * level if the entry isn't present
396 * NOTE: we use ldw even for LP64, since the short pointers
397 * can address up to 1TB
399 .macro L2_ptep pmd,pte,index,va,fault
401 extru \va,31-ASM_PMD_SHIFT,ASM_BITS_PER_PMD,\index
403 extru \va,31-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
405 dep %r0,31,PAGE_SHIFT,\pmd /* clear offset */
407 ldw,s \index(\pmd),\pmd
408 bb,>=,n \pmd,_PxD_PRESENT_BIT,\fault
409 dep %r0,31,PxD_FLAG_SHIFT,\pmd /* clear flags */
411 SHLREG %r9,PxD_VALUE_SHIFT,\pmd
412 extru \va,31-PAGE_SHIFT,ASM_BITS_PER_PTE,\index
413 dep %r0,31,PAGE_SHIFT,\pmd /* clear offset */
414 shladd \index,BITS_PER_PTE_ENTRY,\pmd,\pmd
415 LDREG %r0(\pmd),\pte /* pmd is now pte */
416 bb,>=,n \pte,_PAGE_PRESENT_BIT,\fault
419 /* Look up PTE in a 3-Level scheme.
421 * Here we implement a Hybrid L2/L3 scheme: we allocate the
422 * first pmd adjacent to the pgd. This means that we can
423 * subtract a constant offset to get to it. The pmd and pgd
424 * sizes are arranged so that a single pmd covers 4GB (giving
425 * a full LP64 process access to 8TB) so our lookups are
426 * effectively L2 for the first 4GB of the kernel (i.e. for
427 * all ILP32 processes and all the kernel for machines with
428 * under 4GB of memory) */
429 .macro L3_ptep pgd,pte,index,va,fault
430 #if PT_NLEVELS == 3 /* we might have a 2-Level scheme, e.g. with 16kb page size */
431 extrd,u \va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
433 extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
434 ldw,s \index(\pgd),\pgd
435 extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
436 bb,>=,n \pgd,_PxD_PRESENT_BIT,\fault
437 extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
438 shld \pgd,PxD_VALUE_SHIFT,\index
439 extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
441 extrd,u,*<> \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
442 ldo ASM_PGD_PMD_OFFSET(\pgd),\pgd
444 L2_ptep \pgd,\pte,\index,\va,\fault
447 /* Set the _PAGE_ACCESSED bit of the PTE. Be clever and
448 * don't needlessly dirty the cache line if it was already set */
449 .macro update_ptep ptep,pte,tmp,tmp1
450 ldi _PAGE_ACCESSED,\tmp1
452 and,COND(<>) \tmp1,\pte,%r0
456 /* Set the dirty bit (and accessed bit). No need to be
457 * clever, this is only used from the dirty fault */
458 .macro update_dirty ptep,pte,tmp
459 ldi _PAGE_ACCESSED|_PAGE_DIRTY,\tmp
464 /* bitshift difference between a PFN (based on kernel's PAGE_SIZE)
465 * to a CPU TLB 4k PFN (4k => 12 bits to shift) */
466 #define PAGE_ADD_SHIFT (PAGE_SHIFT-12)
468 /* Drop prot bits and convert to page addr for iitlbt and idtlbt */
469 .macro convert_for_tlb_insert20 pte
470 extrd,u \pte,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
471 64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
472 depdi _PAGE_SIZE_ENCODING_DEFAULT,63,\
473 (63-58)+PAGE_ADD_SHIFT,\pte
476 /* Convert the pte and prot to tlb insertion values. How
477 * this happens is quite subtle, read below */
478 .macro make_insert_tlb spc,pte,prot
479 space_to_prot \spc \prot /* create prot id from space */
480 /* The following is the real subtlety. This is depositing
481 * T <-> _PAGE_REFTRAP
483 * B <-> _PAGE_DMB (memory break)
485 * Then incredible subtlety: The access rights are
486 * _PAGE_GATEWAY _PAGE_EXEC _PAGE_READ
487 * See 3-14 of the parisc 2.0 manual
489 * Finally, _PAGE_READ goes in the top bit of PL1 (so we
490 * trigger an access rights trap in user space if the user
491 * tries to read an unreadable page */
494 /* PAGE_USER indicates the page can be read with user privileges,
495 * so deposit X1|11 to PL1|PL2 (remember the upper bit of PL1
496 * contains _PAGE_READ */
497 extrd,u,*= \pte,_PAGE_USER_BIT+32,1,%r0
499 /* If we're a gateway page, drop PL2 back to zero for promotion
500 * to kernel privilege (so we can execute the page as kernel).
501 * Any privilege promotion page always denys read and write */
502 extrd,u,*= \pte,_PAGE_GATEWAY_BIT+32,1,%r0
503 depd %r0,11,2,\prot /* If Gateway, Set PL2 to 0 */
505 /* Enforce uncacheable pages.
506 * This should ONLY be use for MMIO on PA 2.0 machines.
507 * Memory/DMA is cache coherent on all PA2.0 machines we support
508 * (that means T-class is NOT supported) and the memory controllers
509 * on most of those machines only handles cache transactions.
511 extrd,u,*= \pte,_PAGE_NO_CACHE_BIT+32,1,%r0
514 /* Drop prot bits and convert to page addr for iitlbt and idtlbt */
515 convert_for_tlb_insert20 \pte
518 /* Identical macro to make_insert_tlb above, except it
519 * makes the tlb entry for the differently formatted pa11
520 * insertion instructions */
521 .macro make_insert_tlb_11 spc,pte,prot
522 zdep \spc,30,15,\prot
524 extru,= \pte,_PAGE_NO_CACHE_BIT,1,%r0
526 extru,= \pte,_PAGE_USER_BIT,1,%r0
527 depi 7,11,3,\prot /* Set for user space (1 rsvd for read) */
528 extru,= \pte,_PAGE_GATEWAY_BIT,1,%r0
529 depi 0,11,2,\prot /* If Gateway, Set PL2 to 0 */
531 /* Get rid of prot bits and convert to page addr for iitlba */
533 depi 0,31,ASM_PFN_PTE_SHIFT,\pte
534 SHRREG \pte,(ASM_PFN_PTE_SHIFT-(31-26)),\pte
537 /* This is for ILP32 PA2.0 only. The TLB insertion needs
538 * to extend into I/O space if the address is 0xfXXXXXXX
539 * so we extend the f's into the top word of the pte in
541 .macro f_extend pte,tmp
542 extrd,s \pte,42,4,\tmp
544 extrd,s \pte,63,25,\pte
547 /* The alias region is an 8MB aligned 16MB to do clear and
548 * copy user pages at addresses congruent with the user
551 * To use the alias page, you set %r26 up with the to TLB
552 * entry (identifying the physical page) and %r23 up with
553 * the from tlb entry (or nothing if only a to entry---for
554 * clear_user_page_asm) */
555 .macro do_alias spc,tmp,tmp1,va,pte,prot,fault
556 cmpib,COND(<>),n 0,\spc,\fault
557 ldil L%(TMPALIAS_MAP_START),\tmp
558 #if defined(CONFIG_64BIT) && (TMPALIAS_MAP_START >= 0x80000000)
559 /* on LP64, ldi will sign extend into the upper 32 bits,
560 * which is behaviour we don't want */
565 cmpb,COND(<>),n \tmp,\tmp1,\fault
566 mfctl %cr19,\tmp /* iir */
567 /* get the opcode (first six bits) into \tmp */
568 extrw,u \tmp,5,6,\tmp
570 * Only setting the T bit prevents data cache movein
571 * Setting access rights to zero prevents instruction cache movein
573 * Note subtlety here: _PAGE_GATEWAY, _PAGE_EXEC and _PAGE_WRITE go
574 * to type field and _PAGE_READ goes to top bit of PL1
576 ldi (_PAGE_REFTRAP|_PAGE_READ|_PAGE_WRITE),\prot
578 * so if the opcode is one (i.e. this is a memory management
579 * instruction) nullify the next load so \prot is only T.
580 * Otherwise this is a normal data operation
582 cmpiclr,= 0x01,\tmp,%r0
583 ldi (_PAGE_DIRTY|_PAGE_READ|_PAGE_WRITE),\prot
584 depd,z \prot,8,7,\prot
586 * OK, it is in the temp alias region, check whether "from" or "to".
587 * Check "subtle" note in pacache.S re: r23/r26.
590 extrd,u,*= \va,41,1,%r0
592 extrw,u,= \va,9,1,%r0
594 or,COND(tr) %r23,%r0,\pte
600 * Align fault_vector_20 on 4K boundary so that both
601 * fault_vector_11 and fault_vector_20 are on the
602 * same page. This is only necessary as long as we
603 * write protect the kernel text, which we may stop
604 * doing once we use large page translations to cover
605 * the static part of the kernel address space.
612 ENTRY(fault_vector_20)
613 /* First vector is invalid (0) */
614 .ascii "cows can fly"
655 ENTRY(fault_vector_11)
656 /* First vector is invalid (0) */
657 .ascii "cows can fly"
696 .import handle_interruption,code
697 .import do_cpu_irq_mask,code
700 * r26 = function to be called
701 * r25 = argument to pass in
702 * r24 = flags for do_fork()
704 * Kernel threads don't ever return, so they don't need
705 * a true register context. We just save away the arguments
706 * for copy_thread/ret_ to properly set up the child.
709 #define CLONE_VM 0x100 /* Must agree with <linux/sched.h> */
710 #define CLONE_UNTRACED 0x00800000
713 ENTRY(__kernel_thread)
714 STREG %r2, -RP_OFFSET(%r30)
717 ldo PT_SZ_ALGN(%r30),%r30
719 /* Yo, function pointers in wide mode are little structs... -PB */
721 STREG %r2, PT_GR27(%r1) /* Store childs %dp */
724 STREG %r22, PT_GR22(%r1) /* save r22 (arg5) */
725 copy %r0, %r22 /* user_tid */
727 STREG %r26, PT_GR26(%r1) /* Store function & argument for child */
728 STREG %r25, PT_GR25(%r1)
729 ldil L%CLONE_UNTRACED, %r26
730 ldo CLONE_VM(%r26), %r26 /* Force CLONE_VM since only init_mm */
731 or %r26, %r24, %r26 /* will have kernel mappings. */
732 ldi 1, %r25 /* stack_start, signals kernel thread */
733 stw %r0, -52(%r30) /* user_tid */
735 ldo -16(%r30),%r29 /* Reference param save area */
738 copy %r1, %r24 /* pt_regs */
740 /* Parent Returns here */
742 LDREG -PT_SZ_ALGN-RP_OFFSET(%r30), %r2
743 ldo -PT_SZ_ALGN(%r30), %r30
746 ENDPROC(__kernel_thread)
751 * copy_thread moved args from temp save area set up above
752 * into task save area.
755 ENTRY(ret_from_kernel_thread)
757 /* Call schedule_tail first though */
758 BL schedule_tail, %r2
761 LDREG TI_TASK-THREAD_SZ_ALGN(%r30), %r1
762 LDREG TASK_PT_GR25(%r1), %r26
764 LDREG TASK_PT_GR27(%r1), %r27
765 LDREG TASK_PT_GR22(%r1), %r22
767 LDREG TASK_PT_GR26(%r1), %r1
772 ldo -16(%r30),%r29 /* Reference param save area */
773 loadgp /* Thread could have been in a module */
782 ENDPROC(ret_from_kernel_thread)
784 .import sys_execve, code
788 ldo PT_SZ_ALGN(%r30), %r30
789 STREG %r26, PT_GR26(%r16)
790 STREG %r25, PT_GR25(%r16)
791 STREG %r24, PT_GR24(%r16)
793 ldo -16(%r30),%r29 /* Reference param save area */
798 cmpib,=,n 0,%r28,intr_return /* forward */
800 /* yes, this will trap and die. */
809 * struct task_struct *_switch_to(struct task_struct *prev,
810 * struct task_struct *next)
812 * switch kernel stacks and return prev */
814 STREG %r2, -RP_OFFSET(%r30)
819 load32 _switch_to_ret, %r2
821 STREG %r2, TASK_PT_KPC(%r26)
822 LDREG TASK_PT_KPC(%r25), %r2
824 STREG %r30, TASK_PT_KSP(%r26)
825 LDREG TASK_PT_KSP(%r25), %r30
826 LDREG TASK_THREAD_INFO(%r25), %r25
831 mtctl %r0, %cr0 /* Needed for single stepping */
835 LDREG -RP_OFFSET(%r30), %r2
841 * Common rfi return path for interruptions, kernel execve, and
842 * sys_rt_sigreturn (sometimes). The sys_rt_sigreturn syscall will
843 * return via this path if the signal was received when the process
844 * was running; if the process was blocked on a syscall then the
845 * normal syscall_exit path is used. All syscalls for traced
846 * proceses exit via intr_restore.
848 * XXX If any syscalls that change a processes space id ever exit
849 * this way, then we will need to copy %sr3 in to PT_SR[3..7], and
856 ENTRY(syscall_exit_rfi)
858 LDREG TI_TASK(%r16), %r16 /* thread_info -> task_struct */
859 ldo TASK_REGS(%r16),%r16
860 /* Force iaoq to userspace, as the user has had access to our current
861 * context via sigcontext. Also Filter the PSW for the same reason.
863 LDREG PT_IAOQ0(%r16),%r19
865 STREG %r19,PT_IAOQ0(%r16)
866 LDREG PT_IAOQ1(%r16),%r19
868 STREG %r19,PT_IAOQ1(%r16)
869 LDREG PT_PSW(%r16),%r19
870 load32 USER_PSW_MASK,%r1
872 load32 USER_PSW_HI_MASK,%r20
875 and %r19,%r1,%r19 /* Mask out bits that user shouldn't play with */
877 or %r19,%r1,%r19 /* Make sure default USER_PSW bits are set */
878 STREG %r19,PT_PSW(%r16)
881 * If we aren't being traced, we never saved space registers
882 * (we don't store them in the sigcontext), so set them
883 * to "proper" values now (otherwise we'll wind up restoring
884 * whatever was last stored in the task structure, which might
885 * be inconsistent if an interrupt occured while on the gateway
886 * page). Note that we may be "trashing" values the user put in
887 * them, but we don't support the user changing them.
890 STREG %r0,PT_SR2(%r16)
892 STREG %r19,PT_SR0(%r16)
893 STREG %r19,PT_SR1(%r16)
894 STREG %r19,PT_SR3(%r16)
895 STREG %r19,PT_SR4(%r16)
896 STREG %r19,PT_SR5(%r16)
897 STREG %r19,PT_SR6(%r16)
898 STREG %r19,PT_SR7(%r16)
901 /* NOTE: Need to enable interrupts incase we schedule. */
906 /* check for reschedule */
908 LDREG TI_FLAGS(%r1),%r19 /* sched.h: TIF_NEED_RESCHED */
909 bb,<,n %r19,31-TIF_NEED_RESCHED,intr_do_resched /* forward */
911 .import do_notify_resume,code
915 LDREG TI_FLAGS(%r1),%r19
916 ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK|_TIF_NOTIFY_RESUME), %r20
917 and,COND(<>) %r19, %r20, %r0
918 b,n intr_restore /* skip past if we've nothing to do */
920 /* This check is critical to having LWS
921 * working. The IASQ is zero on the gateway
922 * page and we cannot deliver any signals until
923 * we get off the gateway page.
925 * Only do signals if we are returning to user space
927 LDREG PT_IASQ0(%r16), %r20
928 cmpib,COND(=),n 0,%r20,intr_restore /* backward */
929 LDREG PT_IASQ1(%r16), %r20
930 cmpib,COND(=),n 0,%r20,intr_restore /* backward */
932 copy %r0, %r25 /* long in_syscall = 0 */
934 ldo -16(%r30),%r29 /* Reference param save area */
937 BL do_notify_resume,%r2
938 copy %r16, %r26 /* struct pt_regs *regs */
944 ldo PT_FR31(%r29),%r1
948 /* inverse of virt_map */
950 rsm PSW_SM_QUIET,%r0 /* prepare for rfi */
953 /* Restore space id's and special cr's from PT_REGS
954 * structure pointed to by r29
958 /* IMPORTANT: rest_stack restores r29 last (we are using it)!
959 * It also restores r1 and r30.
966 #ifndef CONFIG_PREEMPT
967 # define intr_do_preempt intr_restore
968 #endif /* !CONFIG_PREEMPT */
970 .import schedule,code
972 /* Only call schedule on return to userspace. If we're returning
973 * to kernel space, we may schedule if CONFIG_PREEMPT, otherwise
974 * we jump back to intr_restore.
976 LDREG PT_IASQ0(%r16), %r20
977 cmpib,COND(=) 0, %r20, intr_do_preempt
979 LDREG PT_IASQ1(%r16), %r20
980 cmpib,COND(=) 0, %r20, intr_do_preempt
984 ldo -16(%r30),%r29 /* Reference param save area */
987 ldil L%intr_check_sig, %r2
991 load32 schedule, %r20
994 ldo R%intr_check_sig(%r2), %r2
996 /* preempt the current task on returning to kernel
997 * mode from an interrupt, iff need_resched is set,
998 * and preempt_count is 0. otherwise, we continue on
999 * our merry way back to the current running task.
1001 #ifdef CONFIG_PREEMPT
1002 .import preempt_schedule_irq,code
1004 rsm PSW_SM_I, %r0 /* disable interrupts */
1006 /* current_thread_info()->preempt_count */
1008 LDREG TI_PRE_COUNT(%r1), %r19
1009 cmpib,COND(<>) 0, %r19, intr_restore /* if preempt_count > 0 */
1010 nop /* prev insn branched backwards */
1012 /* check if we interrupted a critical path */
1013 LDREG PT_PSW(%r16), %r20
1014 bb,<,n %r20, 31 - PSW_SM_I, intr_restore
1017 BL preempt_schedule_irq, %r2
1020 b,n intr_restore /* ssm PSW_SM_I done by intr_restore */
1021 #endif /* CONFIG_PREEMPT */
1024 * External interrupts.
1028 cmpib,COND(=),n 0,%r16,1f
1040 ldo PT_FR0(%r29), %r24
1045 copy %r29, %r26 /* arg0 is pt_regs */
1046 copy %r29, %r16 /* save pt_regs */
1048 ldil L%intr_return, %r2
1051 ldo -16(%r30),%r29 /* Reference param save area */
1055 ldo R%intr_return(%r2), %r2 /* return to intr_return, not here */
1056 ENDPROC(syscall_exit_rfi)
1059 /* Generic interruptions (illegal insn, unaligned, page fault, etc) */
1061 ENTRY(intr_save) /* for os_hpmc */
1063 cmpib,COND(=),n 0,%r16,1f
1075 /* If this trap is a itlb miss, skip saving/adjusting isr/ior */
1078 * FIXME: 1) Use a #define for the hardwired "6" below (and in
1080 * 2) Once we start executing code above 4 Gb, we need
1081 * to adjust iasq/iaoq here in the same way we
1082 * adjust isr/ior below.
1085 cmpib,COND(=),n 6,%r26,skip_save_ior
1088 mfctl %cr20, %r16 /* isr */
1089 nop /* serialize mfctl on PA 2.0 to avoid 4 cycle penalty */
1090 mfctl %cr21, %r17 /* ior */
1095 * If the interrupted code was running with W bit off (32 bit),
1096 * clear the b bits (bits 0 & 1) in the ior.
1097 * save_specials left ipsw value in r8 for us to test.
1099 extrd,u,*<> %r8,PSW_W_BIT,1,%r0
1103 * FIXME: This code has hardwired assumptions about the split
1104 * between space bits and offset bits. This will change
1105 * when we allow alternate page sizes.
1108 /* adjust isr/ior. */
1109 extrd,u %r16,63,SPACEID_SHIFT,%r1 /* get high bits from isr for ior */
1110 depd %r1,31,SPACEID_SHIFT,%r17 /* deposit them into ior */
1111 depdi 0,63,SPACEID_SHIFT,%r16 /* clear them from isr */
1113 STREG %r16, PT_ISR(%r29)
1114 STREG %r17, PT_IOR(%r29)
1121 ldo PT_FR0(%r29), %r25
1126 copy %r29, %r25 /* arg1 is pt_regs */
1128 ldo -16(%r30),%r29 /* Reference param save area */
1131 ldil L%intr_check_sig, %r2
1132 copy %r25, %r16 /* save pt_regs */
1134 b handle_interruption
1135 ldo R%intr_check_sig(%r2), %r2
1140 * Note for all tlb miss handlers:
1142 * cr24 contains a pointer to the kernel address space
1145 * cr25 contains a pointer to the current user address
1146 * space page directory.
1148 * sr3 will contain the space id of the user address space
1149 * of the current running thread while that thread is
1150 * running in the kernel.
1154 * register number allocations. Note that these are all
1155 * in the shadowed registers
1158 t0 = r1 /* temporary register 0 */
1159 va = r8 /* virtual address for which the trap occured */
1160 t1 = r9 /* temporary register 1 */
1161 pte = r16 /* pte/phys page # */
1162 prot = r17 /* prot bits */
1163 spc = r24 /* space for which the trap occured */
1164 ptp = r25 /* page directory/page table pointer */
1169 space_adjust spc,va,t0
1171 space_check spc,t0,dtlb_fault
1173 L3_ptep ptp,pte,t0,va,dtlb_check_alias_20w
1175 update_ptep ptp,pte,t0,t1
1177 make_insert_tlb spc,pte,prot
1184 dtlb_check_alias_20w:
1185 do_alias spc,t0,t1,va,pte,prot,dtlb_fault
1193 space_adjust spc,va,t0
1195 space_check spc,t0,nadtlb_fault
1197 L3_ptep ptp,pte,t0,va,nadtlb_check_alias_20w
1199 update_ptep ptp,pte,t0,t1
1201 make_insert_tlb spc,pte,prot
1208 nadtlb_check_alias_20w:
1209 do_alias spc,t0,t1,va,pte,prot,nadtlb_check_flush_20w
1216 nadtlb_check_flush_20w:
1217 bb,>=,n pte,_PAGE_FLUSH_BIT,nadtlb_emulate
1219 /* Insert a "flush only" translation */
1224 /* Drop prot bits from pte and convert to page addr for idtlbt */
1225 convert_for_tlb_insert20 pte
1237 space_check spc,t0,dtlb_fault
1239 L2_ptep ptp,pte,t0,va,dtlb_check_alias_11
1241 update_ptep ptp,pte,t0,t1
1243 make_insert_tlb_11 spc,pte,prot
1245 mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
1248 idtlba pte,(%sr1,va)
1249 idtlbp prot,(%sr1,va)
1251 mtsp t0, %sr1 /* Restore sr1 */
1256 dtlb_check_alias_11:
1257 do_alias spc,t0,t1,va,pte,prot,dtlb_fault
1268 space_check spc,t0,nadtlb_fault
1270 L2_ptep ptp,pte,t0,va,nadtlb_check_alias_11
1272 update_ptep ptp,pte,t0,t1
1274 make_insert_tlb_11 spc,pte,prot
1277 mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
1280 idtlba pte,(%sr1,va)
1281 idtlbp prot,(%sr1,va)
1283 mtsp t0, %sr1 /* Restore sr1 */
1288 nadtlb_check_alias_11:
1289 do_alias spc,t0,t1,va,pte,prot,nadtlb_check_flush_11
1297 nadtlb_check_flush_11:
1298 bb,>=,n pte,_PAGE_FLUSH_BIT,nadtlb_emulate
1300 /* Insert a "flush only" translation */
1305 /* Get rid of prot bits and convert to page addr for idtlba */
1307 depi 0,31,ASM_PFN_PTE_SHIFT,pte
1308 SHRREG pte,(ASM_PFN_PTE_SHIFT-(31-26)),pte
1310 mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
1313 idtlba pte,(%sr1,va)
1314 idtlbp prot,(%sr1,va)
1316 mtsp t0, %sr1 /* Restore sr1 */
1322 space_adjust spc,va,t0
1324 space_check spc,t0,dtlb_fault
1326 L2_ptep ptp,pte,t0,va,dtlb_check_alias_20
1328 update_ptep ptp,pte,t0,t1
1330 make_insert_tlb spc,pte,prot
1339 dtlb_check_alias_20:
1340 do_alias spc,t0,t1,va,pte,prot,dtlb_fault
1350 space_check spc,t0,nadtlb_fault
1352 L2_ptep ptp,pte,t0,va,nadtlb_check_alias_20
1354 update_ptep ptp,pte,t0,t1
1356 make_insert_tlb spc,pte,prot
1365 nadtlb_check_alias_20:
1366 do_alias spc,t0,t1,va,pte,prot,nadtlb_check_flush_20
1373 nadtlb_check_flush_20:
1374 bb,>=,n pte,_PAGE_FLUSH_BIT,nadtlb_emulate
1376 /* Insert a "flush only" translation */
1381 /* Drop prot bits from pte and convert to page addr for idtlbt */
1382 convert_for_tlb_insert20 pte
1393 * Non access misses can be caused by fdc,fic,pdc,lpa,probe and
1394 * probei instructions. We don't want to fault for these
1395 * instructions (not only does it not make sense, it can cause
1396 * deadlocks, since some flushes are done with the mmap
1397 * semaphore held). If the translation doesn't exist, we can't
1398 * insert a translation, so have to emulate the side effects
1399 * of the instruction. Since we don't insert a translation
1400 * we can get a lot of faults during a flush loop, so it makes
1401 * sense to try to do it here with minimum overhead. We only
1402 * emulate fdc,fic,pdc,probew,prober instructions whose base
1403 * and index registers are not shadowed. We defer everything
1404 * else to the "slow" path.
1407 mfctl %cr19,%r9 /* Get iir */
1409 /* PA 2.0 Arch Ref. Book pg 382 has a good description of the insn bits.
1410 Checks for fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw */
1412 /* Checks for fdc,fdce,pdc,"fic,4f" only */
1415 cmpb,<>,n %r16,%r17,nadtlb_probe_check
1416 bb,>=,n %r9,26,nadtlb_nullify /* m bit not set, just nullify */
1417 BL get_register,%r25
1418 extrw,u %r9,15,5,%r8 /* Get index register # */
1419 cmpib,COND(=),n -1,%r1,nadtlb_fault /* have to use slow path */
1421 BL get_register,%r25
1422 extrw,u %r9,10,5,%r8 /* Get base register # */
1423 cmpib,COND(=),n -1,%r1,nadtlb_fault /* have to use slow path */
1424 BL set_register,%r25
1425 add,l %r1,%r24,%r1 /* doesn't affect c/b bits */
1430 or %r8,%r9,%r8 /* Set PSW_N */
1437 When there is no translation for the probe address then we
1438 must nullify the insn and return zero in the target regsiter.
1439 This will indicate to the calling code that it does not have
1440 write/read privileges to this address.
1442 This should technically work for prober and probew in PA 1.1,
1443 and also probe,r and probe,w in PA 2.0
1445 WARNING: USE ONLY NON-SHADOW REGISTERS WITH PROBE INSN!
1446 THE SLOW-PATH EMULATION HAS NOT BEEN WRITTEN YET.
1452 cmpb,<>,n %r16,%r17,nadtlb_fault /* Must be probe,[rw]*/
1453 BL get_register,%r25 /* Find the target register */
1454 extrw,u %r9,31,5,%r8 /* Get target register */
1455 cmpib,COND(=),n -1,%r1,nadtlb_fault /* have to use slow path */
1456 BL set_register,%r25
1457 copy %r0,%r1 /* Write zero to target register */
1458 b nadtlb_nullify /* Nullify return insn */
1466 * I miss is a little different, since we allow users to fault
1467 * on the gateway page which is in the kernel address space.
1470 space_adjust spc,va,t0
1472 space_check spc,t0,itlb_fault
1474 L3_ptep ptp,pte,t0,va,itlb_fault
1476 update_ptep ptp,pte,t0,t1
1478 make_insert_tlb spc,pte,prot
1488 * I miss is a little different, since we allow users to fault
1489 * on the gateway page which is in the kernel address space.
1492 space_adjust spc,va,t0
1494 space_check spc,t0,naitlb_fault
1496 L3_ptep ptp,pte,t0,va,naitlb_check_alias_20w
1498 update_ptep ptp,pte,t0,t1
1500 make_insert_tlb spc,pte,prot
1507 naitlb_check_alias_20w:
1508 do_alias spc,t0,t1,va,pte,prot,naitlb_fault
1520 space_check spc,t0,itlb_fault
1522 L2_ptep ptp,pte,t0,va,itlb_fault
1524 update_ptep ptp,pte,t0,t1
1526 make_insert_tlb_11 spc,pte,prot
1528 mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
1531 iitlba pte,(%sr1,va)
1532 iitlbp prot,(%sr1,va)
1534 mtsp t0, %sr1 /* Restore sr1 */
1542 space_check spc,t0,naitlb_fault
1544 L2_ptep ptp,pte,t0,va,naitlb_check_alias_11
1546 update_ptep ptp,pte,t0,t1
1548 make_insert_tlb_11 spc,pte,prot
1550 mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
1553 iitlba pte,(%sr1,va)
1554 iitlbp prot,(%sr1,va)
1556 mtsp t0, %sr1 /* Restore sr1 */
1561 naitlb_check_alias_11:
1562 do_alias spc,t0,t1,va,pte,prot,itlb_fault
1564 iitlba pte,(%sr0, va)
1565 iitlbp prot,(%sr0, va)
1574 space_check spc,t0,itlb_fault
1576 L2_ptep ptp,pte,t0,va,itlb_fault
1578 update_ptep ptp,pte,t0,t1
1580 make_insert_tlb spc,pte,prot
1592 space_check spc,t0,naitlb_fault
1594 L2_ptep ptp,pte,t0,va,naitlb_check_alias_20
1596 update_ptep ptp,pte,t0,t1
1598 make_insert_tlb spc,pte,prot
1607 naitlb_check_alias_20:
1608 do_alias spc,t0,t1,va,pte,prot,naitlb_fault
1620 space_adjust spc,va,t0
1622 space_check spc,t0,dbit_fault
1624 L3_ptep ptp,pte,t0,va,dbit_fault
1627 cmpib,COND(=),n 0,spc,dbit_nolock_20w
1628 load32 PA(pa_dbit_lock),t0
1632 cmpib,COND(=) 0,t1,dbit_spin_20w
1637 update_dirty ptp,pte,t1
1639 make_insert_tlb spc,pte,prot
1643 cmpib,COND(=),n 0,spc,dbit_nounlock_20w
1658 space_check spc,t0,dbit_fault
1660 L2_ptep ptp,pte,t0,va,dbit_fault
1663 cmpib,COND(=),n 0,spc,dbit_nolock_11
1664 load32 PA(pa_dbit_lock),t0
1668 cmpib,= 0,t1,dbit_spin_11
1673 update_dirty ptp,pte,t1
1675 make_insert_tlb_11 spc,pte,prot
1677 mfsp %sr1,t1 /* Save sr1 so we can use it in tlb inserts */
1680 idtlba pte,(%sr1,va)
1681 idtlbp prot,(%sr1,va)
1683 mtsp t1, %sr1 /* Restore sr1 */
1685 cmpib,COND(=),n 0,spc,dbit_nounlock_11
1698 space_check spc,t0,dbit_fault
1700 L2_ptep ptp,pte,t0,va,dbit_fault
1703 cmpib,COND(=),n 0,spc,dbit_nolock_20
1704 load32 PA(pa_dbit_lock),t0
1708 cmpib,= 0,t1,dbit_spin_20
1713 update_dirty ptp,pte,t1
1715 make_insert_tlb spc,pte,prot
1722 cmpib,COND(=),n 0,spc,dbit_nounlock_20
1733 .import handle_interruption,code
1737 ldi 31,%r8 /* Use an unused code */
1759 /* Register saving semantics for system calls:
1761 %r1 clobbered by system call macro in userspace
1762 %r2 saved in PT_REGS by gateway page
1763 %r3 - %r18 preserved by C code (saved by signal code)
1764 %r19 - %r20 saved in PT_REGS by gateway page
1765 %r21 - %r22 non-standard syscall args
1766 stored in kernel stack by gateway page
1767 %r23 - %r26 arg3-arg0, saved in PT_REGS by gateway page
1768 %r27 - %r30 saved in PT_REGS by gateway page
1769 %r31 syscall return pointer
1772 /* Floating point registers (FIXME: what do we do with these?)
1774 %fr0 - %fr3 status/exception, not preserved
1775 %fr4 - %fr7 arguments
1776 %fr8 - %fr11 not preserved by C code
1777 %fr12 - %fr21 preserved by C code
1778 %fr22 - %fr31 not preserved by C code
1781 .macro reg_save regs
1782 STREG %r3, PT_GR3(\regs)
1783 STREG %r4, PT_GR4(\regs)
1784 STREG %r5, PT_GR5(\regs)
1785 STREG %r6, PT_GR6(\regs)
1786 STREG %r7, PT_GR7(\regs)
1787 STREG %r8, PT_GR8(\regs)
1788 STREG %r9, PT_GR9(\regs)
1789 STREG %r10,PT_GR10(\regs)
1790 STREG %r11,PT_GR11(\regs)
1791 STREG %r12,PT_GR12(\regs)
1792 STREG %r13,PT_GR13(\regs)
1793 STREG %r14,PT_GR14(\regs)
1794 STREG %r15,PT_GR15(\regs)
1795 STREG %r16,PT_GR16(\regs)
1796 STREG %r17,PT_GR17(\regs)
1797 STREG %r18,PT_GR18(\regs)
1800 .macro reg_restore regs
1801 LDREG PT_GR3(\regs), %r3
1802 LDREG PT_GR4(\regs), %r4
1803 LDREG PT_GR5(\regs), %r5
1804 LDREG PT_GR6(\regs), %r6
1805 LDREG PT_GR7(\regs), %r7
1806 LDREG PT_GR8(\regs), %r8
1807 LDREG PT_GR9(\regs), %r9
1808 LDREG PT_GR10(\regs),%r10
1809 LDREG PT_GR11(\regs),%r11
1810 LDREG PT_GR12(\regs),%r12
1811 LDREG PT_GR13(\regs),%r13
1812 LDREG PT_GR14(\regs),%r14
1813 LDREG PT_GR15(\regs),%r15
1814 LDREG PT_GR16(\regs),%r16
1815 LDREG PT_GR17(\regs),%r17
1816 LDREG PT_GR18(\regs),%r18
1819 ENTRY(sys_fork_wrapper)
1820 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
1821 ldo TASK_REGS(%r1),%r1
1824 STREG %r3, PT_CR27(%r1)
1826 STREG %r2,-RP_OFFSET(%r30)
1827 ldo FRAME_SIZE(%r30),%r30
1829 ldo -16(%r30),%r29 /* Reference param save area */
1832 /* These are call-clobbered registers and therefore
1833 also syscall-clobbered (we hope). */
1834 STREG %r2,PT_GR19(%r1) /* save for child */
1835 STREG %r30,PT_GR21(%r1)
1837 LDREG PT_GR30(%r1),%r25
1842 LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2
1844 ldo -FRAME_SIZE(%r30),%r30 /* get the stackframe */
1845 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1846 ldo TASK_REGS(%r1),%r1 /* get pt regs */
1848 LDREG PT_CR27(%r1), %r3
1852 /* strace expects syscall # to be preserved in r20 */
1855 STREG %r20,PT_GR20(%r1)
1856 ENDPROC(sys_fork_wrapper)
1858 /* Set the return value for the child */
1860 BL schedule_tail, %r2
1863 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE-FRAME_SIZE(%r30), %r1
1864 LDREG TASK_PT_GR19(%r1),%r2
1867 ENDPROC(child_return)
1870 ENTRY(sys_clone_wrapper)
1871 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1872 ldo TASK_REGS(%r1),%r1 /* get pt regs */
1875 STREG %r3, PT_CR27(%r1)
1877 STREG %r2,-RP_OFFSET(%r30)
1878 ldo FRAME_SIZE(%r30),%r30
1880 ldo -16(%r30),%r29 /* Reference param save area */
1883 /* WARNING - Clobbers r19 and r21, userspace must save these! */
1884 STREG %r2,PT_GR19(%r1) /* save for child */
1885 STREG %r30,PT_GR21(%r1)
1890 LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2
1891 ENDPROC(sys_clone_wrapper)
1894 ENTRY(sys_vfork_wrapper)
1895 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1896 ldo TASK_REGS(%r1),%r1 /* get pt regs */
1899 STREG %r3, PT_CR27(%r1)
1901 STREG %r2,-RP_OFFSET(%r30)
1902 ldo FRAME_SIZE(%r30),%r30
1904 ldo -16(%r30),%r29 /* Reference param save area */
1907 STREG %r2,PT_GR19(%r1) /* save for child */
1908 STREG %r30,PT_GR21(%r1)
1914 LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2
1915 ENDPROC(sys_vfork_wrapper)
1918 .macro execve_wrapper execve
1919 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1920 ldo TASK_REGS(%r1),%r1 /* get pt regs */
1923 * Do we need to save/restore r3-r18 here?
1924 * I don't think so. why would new thread need old
1925 * threads registers?
1928 /* %arg0 - %arg3 are already saved for us. */
1930 STREG %r2,-RP_OFFSET(%r30)
1931 ldo FRAME_SIZE(%r30),%r30
1933 ldo -16(%r30),%r29 /* Reference param save area */
1938 ldo -FRAME_SIZE(%r30),%r30
1939 LDREG -RP_OFFSET(%r30),%r2
1941 /* If exec succeeded we need to load the args */
1944 cmpb,>>= %r28,%r1,error_\execve
1953 ENTRY(sys_execve_wrapper)
1954 execve_wrapper sys_execve
1955 ENDPROC(sys_execve_wrapper)
1958 .import sys32_execve
1959 ENTRY(sys32_execve_wrapper)
1960 execve_wrapper sys32_execve
1961 ENDPROC(sys32_execve_wrapper)
1964 ENTRY(sys_rt_sigreturn_wrapper)
1965 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26
1966 ldo TASK_REGS(%r26),%r26 /* get pt regs */
1967 /* Don't save regs, we are going to restore them from sigcontext. */
1968 STREG %r2, -RP_OFFSET(%r30)
1970 ldo FRAME_SIZE(%r30), %r30
1971 BL sys_rt_sigreturn,%r2
1972 ldo -16(%r30),%r29 /* Reference param save area */
1974 BL sys_rt_sigreturn,%r2
1975 ldo FRAME_SIZE(%r30), %r30
1978 ldo -FRAME_SIZE(%r30), %r30
1979 LDREG -RP_OFFSET(%r30), %r2
1981 /* FIXME: I think we need to restore a few more things here. */
1982 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1983 ldo TASK_REGS(%r1),%r1 /* get pt regs */
1986 /* If the signal was received while the process was blocked on a
1987 * syscall, then r2 will take us to syscall_exit; otherwise r2 will
1988 * take us to syscall_exit_rfi and on to intr_return.
1991 LDREG PT_GR28(%r1),%r28 /* reload original r28 for syscall_exit */
1992 ENDPROC(sys_rt_sigreturn_wrapper)
1994 ENTRY(sys_sigaltstack_wrapper)
1995 /* Get the user stack pointer */
1996 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1997 ldo TASK_REGS(%r1),%r24 /* get pt regs */
1998 LDREG TASK_PT_GR30(%r24),%r24
1999 STREG %r2, -RP_OFFSET(%r30)
2001 ldo FRAME_SIZE(%r30), %r30
2002 BL do_sigaltstack,%r2
2003 ldo -16(%r30),%r29 /* Reference param save area */
2005 BL do_sigaltstack,%r2
2006 ldo FRAME_SIZE(%r30), %r30
2009 ldo -FRAME_SIZE(%r30), %r30
2010 LDREG -RP_OFFSET(%r30), %r2
2013 ENDPROC(sys_sigaltstack_wrapper)
2016 ENTRY(sys32_sigaltstack_wrapper)
2017 /* Get the user stack pointer */
2018 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r24
2019 LDREG TASK_PT_GR30(%r24),%r24
2020 STREG %r2, -RP_OFFSET(%r30)
2021 ldo FRAME_SIZE(%r30), %r30
2022 BL do_sigaltstack32,%r2
2023 ldo -16(%r30),%r29 /* Reference param save area */
2025 ldo -FRAME_SIZE(%r30), %r30
2026 LDREG -RP_OFFSET(%r30), %r2
2029 ENDPROC(sys32_sigaltstack_wrapper)
2033 /* NOTE: HP-UX syscalls also come through here
2034 * after hpux_syscall_exit fixes up return
2037 /* NOTE: Not all syscalls exit this way. rt_sigreturn will exit
2038 * via syscall_exit_rfi if the signal was received while the process
2042 /* save return value now */
2045 LDREG TI_TASK(%r1),%r1
2046 STREG %r28,TASK_PT_GR28(%r1)
2049 /* <linux/personality.h> cannot be easily included */
2050 #define PER_HPUX 0x10
2051 ldw TASK_PERSONALITY(%r1),%r19
2053 /* We can't use "CMPIB<> PER_HPUX" since "im5" field is sign extended */
2054 ldo -PER_HPUX(%r19), %r19
2055 cmpib,COND(<>),n 0,%r19,1f
2057 /* Save other hpux returns if personality is PER_HPUX */
2058 STREG %r22,TASK_PT_GR22(%r1)
2059 STREG %r29,TASK_PT_GR29(%r1)
2062 #endif /* CONFIG_HPUX */
2064 /* Seems to me that dp could be wrong here, if the syscall involved
2065 * calling a module, and nothing got round to restoring dp on return.
2069 syscall_check_resched:
2071 /* check for reschedule */
2073 LDREG TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19 /* long */
2074 bb,<,n %r19, 31-TIF_NEED_RESCHED, syscall_do_resched /* forward */
2076 .import do_signal,code
2078 LDREG TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19
2079 ldi (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK), %r26
2080 and,COND(<>) %r19, %r26, %r0
2081 b,n syscall_restore /* skip past if we've nothing to do */
2084 /* Save callee-save registers (for sigcontext).
2085 * FIXME: After this point the process structure should be
2086 * consistent with all the relevant state of the process
2087 * before the syscall. We need to verify this.
2089 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
2090 ldo TASK_REGS(%r1), %r26 /* struct pt_regs *regs */
2094 ldo -16(%r30),%r29 /* Reference param save area */
2097 BL do_notify_resume,%r2
2098 ldi 1, %r25 /* long in_syscall = 1 */
2100 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
2101 ldo TASK_REGS(%r1), %r20 /* reload pt_regs */
2104 b,n syscall_check_sig
2107 LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
2109 /* Are we being ptraced? */
2110 ldw TASK_FLAGS(%r1),%r19
2111 ldi (_TIF_SINGLESTEP|_TIF_BLOCKSTEP),%r2
2112 and,COND(=) %r19,%r2,%r0
2113 b,n syscall_restore_rfi
2115 ldo TASK_PT_FR31(%r1),%r19 /* reload fpregs */
2118 LDREG TASK_PT_SAR(%r1),%r19 /* restore SAR */
2121 LDREG TASK_PT_GR2(%r1),%r2 /* restore user rp */
2122 LDREG TASK_PT_GR19(%r1),%r19
2123 LDREG TASK_PT_GR20(%r1),%r20
2124 LDREG TASK_PT_GR21(%r1),%r21
2125 LDREG TASK_PT_GR22(%r1),%r22
2126 LDREG TASK_PT_GR23(%r1),%r23
2127 LDREG TASK_PT_GR24(%r1),%r24
2128 LDREG TASK_PT_GR25(%r1),%r25
2129 LDREG TASK_PT_GR26(%r1),%r26
2130 LDREG TASK_PT_GR27(%r1),%r27 /* restore user dp */
2131 LDREG TASK_PT_GR28(%r1),%r28 /* syscall return value */
2132 LDREG TASK_PT_GR29(%r1),%r29
2133 LDREG TASK_PT_GR31(%r1),%r31 /* restore syscall rp */
2135 /* NOTE: We use rsm/ssm pair to make this operation atomic */
2136 LDREG TASK_PT_GR30(%r1),%r1 /* Get user sp */
2138 copy %r1,%r30 /* Restore user sp */
2139 mfsp %sr3,%r1 /* Get user space id */
2140 mtsp %r1,%sr7 /* Restore sr7 */
2143 /* Set sr2 to zero for userspace syscalls to work. */
2145 mtsp %r1,%sr4 /* Restore sr4 */
2146 mtsp %r1,%sr5 /* Restore sr5 */
2147 mtsp %r1,%sr6 /* Restore sr6 */
2149 depi 3,31,2,%r31 /* ensure return to user mode. */
2152 /* decide whether to reset the wide mode bit
2154 * For a syscall, the W bit is stored in the lowest bit
2155 * of sp. Extract it and reset W if it is zero */
2156 extrd,u,*<> %r30,63,1,%r1
2158 /* now reset the lowest bit of sp if it was set */
2161 be,n 0(%sr3,%r31) /* return to user space */
2163 /* We have to return via an RFI, so that PSW T and R bits can be set
2165 * This sets up pt_regs so we can return via intr_restore, which is not
2166 * the most efficient way of doing things, but it works.
2168 syscall_restore_rfi:
2169 ldo -1(%r0),%r2 /* Set recovery cntr to -1 */
2170 mtctl %r2,%cr0 /* for immediate trap */
2171 LDREG TASK_PT_PSW(%r1),%r2 /* Get old PSW */
2172 ldi 0x0b,%r20 /* Create new PSW */
2173 depi -1,13,1,%r20 /* C, Q, D, and I bits */
2175 /* The values of SINGLESTEP_BIT and BLOCKSTEP_BIT are
2176 * set in thread_info.h and converted to PA bitmap
2177 * numbers in asm-offsets.c */
2179 /* if ((%r19.SINGLESTEP_BIT)) { %r20.27=1} */
2180 extru,= %r19,TIF_SINGLESTEP_PA_BIT,1,%r0
2181 depi -1,27,1,%r20 /* R bit */
2183 /* if ((%r19.BLOCKSTEP_BIT)) { %r20.7=1} */
2184 extru,= %r19,TIF_BLOCKSTEP_PA_BIT,1,%r0
2185 depi -1,7,1,%r20 /* T bit */
2187 STREG %r20,TASK_PT_PSW(%r1)
2189 /* Always store space registers, since sr3 can be changed (e.g. fork) */
2192 STREG %r25,TASK_PT_SR3(%r1)
2193 STREG %r25,TASK_PT_SR4(%r1)
2194 STREG %r25,TASK_PT_SR5(%r1)
2195 STREG %r25,TASK_PT_SR6(%r1)
2196 STREG %r25,TASK_PT_SR7(%r1)
2197 STREG %r25,TASK_PT_IASQ0(%r1)
2198 STREG %r25,TASK_PT_IASQ1(%r1)
2201 /* Now if old D bit is clear, it means we didn't save all registers
2202 * on syscall entry, so do that now. This only happens on TRACEME
2203 * calls, or if someone attached to us while we were on a syscall.
2204 * We could make this more efficient by not saving r3-r18, but
2205 * then we wouldn't be able to use the common intr_restore path.
2206 * It is only for traced processes anyway, so performance is not
2209 bb,< %r2,30,pt_regs_ok /* Branch if D set */
2210 ldo TASK_REGS(%r1),%r25
2211 reg_save %r25 /* Save r3 to r18 */
2213 /* Save the current sr */
2215 STREG %r2,TASK_PT_SR0(%r1)
2217 /* Save the scratch sr */
2219 STREG %r2,TASK_PT_SR1(%r1)
2221 /* sr2 should be set to zero for userspace syscalls */
2222 STREG %r0,TASK_PT_SR2(%r1)
2225 LDREG TASK_PT_GR31(%r1),%r2
2226 depi 3,31,2,%r2 /* ensure return to user mode. */
2227 STREG %r2,TASK_PT_IAOQ0(%r1)
2229 STREG %r2,TASK_PT_IAOQ1(%r1)
2234 .import schedule,code
2238 ldo -16(%r30),%r29 /* Reference param save area */
2242 b syscall_check_resched /* if resched, we start over again */
2244 ENDPROC(syscall_exit)
2247 #ifdef CONFIG_FUNCTION_TRACER
2248 .import ftrace_function_trampoline,code
2251 b ftrace_function_trampoline
2255 ENTRY(return_to_handler)
2256 load32 return_trampoline, %rp
2259 b ftrace_return_to_handler
2270 ENDPROC(return_to_handler)
2271 #endif /* CONFIG_FUNCTION_TRACER */
2276 * get_register is used by the non access tlb miss handlers to
2277 * copy the value of the general register specified in r8 into
2278 * r1. This routine can't be used for shadowed registers, since
2279 * the rfir will restore the original value. So, for the shadowed
2280 * registers we put a -1 into r1 to indicate that the register
2281 * should not be used (the register being copied could also have
2282 * a -1 in it, but that is OK, it just means that we will have
2283 * to use the slow path instead).
2287 bv %r0(%r25) /* r0 */
2289 bv %r0(%r25) /* r1 - shadowed */
2291 bv %r0(%r25) /* r2 */
2293 bv %r0(%r25) /* r3 */
2295 bv %r0(%r25) /* r4 */
2297 bv %r0(%r25) /* r5 */
2299 bv %r0(%r25) /* r6 */
2301 bv %r0(%r25) /* r7 */
2303 bv %r0(%r25) /* r8 - shadowed */
2305 bv %r0(%r25) /* r9 - shadowed */
2307 bv %r0(%r25) /* r10 */
2309 bv %r0(%r25) /* r11 */
2311 bv %r0(%r25) /* r12 */
2313 bv %r0(%r25) /* r13 */
2315 bv %r0(%r25) /* r14 */
2317 bv %r0(%r25) /* r15 */
2319 bv %r0(%r25) /* r16 - shadowed */
2321 bv %r0(%r25) /* r17 - shadowed */
2323 bv %r0(%r25) /* r18 */
2325 bv %r0(%r25) /* r19 */
2327 bv %r0(%r25) /* r20 */
2329 bv %r0(%r25) /* r21 */
2331 bv %r0(%r25) /* r22 */
2333 bv %r0(%r25) /* r23 */
2335 bv %r0(%r25) /* r24 - shadowed */
2337 bv %r0(%r25) /* r25 - shadowed */
2339 bv %r0(%r25) /* r26 */
2341 bv %r0(%r25) /* r27 */
2343 bv %r0(%r25) /* r28 */
2345 bv %r0(%r25) /* r29 */
2347 bv %r0(%r25) /* r30 */
2349 bv %r0(%r25) /* r31 */
2355 * set_register is used by the non access tlb miss handlers to
2356 * copy the value of r1 into the general register specified in
2361 bv %r0(%r25) /* r0 (silly, but it is a place holder) */
2363 bv %r0(%r25) /* r1 */
2365 bv %r0(%r25) /* r2 */
2367 bv %r0(%r25) /* r3 */
2369 bv %r0(%r25) /* r4 */
2371 bv %r0(%r25) /* r5 */
2373 bv %r0(%r25) /* r6 */
2375 bv %r0(%r25) /* r7 */
2377 bv %r0(%r25) /* r8 */
2379 bv %r0(%r25) /* r9 */
2381 bv %r0(%r25) /* r10 */
2383 bv %r0(%r25) /* r11 */
2385 bv %r0(%r25) /* r12 */
2387 bv %r0(%r25) /* r13 */
2389 bv %r0(%r25) /* r14 */
2391 bv %r0(%r25) /* r15 */
2393 bv %r0(%r25) /* r16 */
2395 bv %r0(%r25) /* r17 */
2397 bv %r0(%r25) /* r18 */
2399 bv %r0(%r25) /* r19 */
2401 bv %r0(%r25) /* r20 */
2403 bv %r0(%r25) /* r21 */
2405 bv %r0(%r25) /* r22 */
2407 bv %r0(%r25) /* r23 */
2409 bv %r0(%r25) /* r24 */
2411 bv %r0(%r25) /* r25 */
2413 bv %r0(%r25) /* r26 */
2415 bv %r0(%r25) /* r27 */
2417 bv %r0(%r25) /* r28 */
2419 bv %r0(%r25) /* r29 */
2421 bv %r0(%r25) /* r30 */
2423 bv %r0(%r25) /* r31 */