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+/*
+ * Linux/PA-RISC Project (http://www.parisc-linux.org/)
+ *
+ * kernel entry points (interruptions, system call wrappers)
+ * Copyright (C) 1999,2000 Philipp Rumpf
+ * Copyright (C) 1999 SuSE GmbH Nuernberg
+ * Copyright (C) 2000 Hewlett-Packard (John Marvin)
+ * Copyright (C) 1999 Hewlett-Packard (Frank Rowand)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/config.h>
+#include <asm/offsets.h>
+
+/* we have the following possibilities to act on an interruption:
+ * - handle in assembly and use shadowed registers only
+ * - save registers to kernel stack and handle in assembly or C */
+
+
+#include <asm/assembly.h> /* for LDREG/STREG defines */
+#include <asm/pgtable.h>
+#include <asm/psw.h>
+#include <asm/signal.h>
+#include <asm/unistd.h>
+#include <asm/thread_info.h>
+
+#ifdef __LP64__
+#define CMPIB cmpib,*
+#define CMPB cmpb,*
+#define COND(x) *x
+
+ .level 2.0w
+#else
+#define CMPIB cmpib,
+#define CMPB cmpb,
+#define COND(x) x
+
+ .level 2.0
+#endif
+
+ .import pa_dbit_lock,data
+
+ /* space_to_prot macro creates a prot id from a space id */
+
+#if (SPACEID_SHIFT) == 0
+ .macro space_to_prot spc prot
+ depd,z \spc,62,31,\prot
+ .endm
+#else
+ .macro space_to_prot spc prot
+ extrd,u \spc,(64 - (SPACEID_SHIFT)),32,\prot
+ .endm
+#endif
+
+ /* Switch to virtual mapping, trashing only %r1 */
+ .macro virt_map
+ rsm PSW_SM_Q,%r0
+ tovirt_r1 %r29
+ mfsp %sr7, %r1
+ or,= %r0,%r1,%r0 /* Only save sr7 in sr3 if sr7 != 0 */
+ mtsp %r1, %sr3
+ mtsp %r0, %sr4
+ mtsp %r0, %sr5
+ mtsp %r0, %sr6
+ mtsp %r0, %sr7
+ load32 KERNEL_PSW, %r1
+ mtctl %r1, %cr22
+ mtctl %r0, %cr17 /* Clear IIASQ tail */
+ mtctl %r0, %cr17 /* Clear IIASQ head */
+ load32 4f, %r1
+ mtctl %r1, %cr18 /* Set IIAOQ tail */
+ ldo 4(%r1), %r1
+ mtctl %r1, %cr18 /* Set IIAOQ head */
+ rfir
+ nop
+4:
+ .endm
+
+ /*
+ * The "get_stack" macros are responsible for determining the
+ * kernel stack value.
+ *
+ * For Faults:
+ * If sr7 == 0
+ * Already using a kernel stack, so call the
+ * get_stack_use_r30 macro to push a pt_regs structure
+ * on the stack, and store registers there.
+ * else
+ * Need to set up a kernel stack, so call the
+ * get_stack_use_cr30 macro to set up a pointer
+ * to the pt_regs structure contained within the
+ * task pointer pointed to by cr30. Set the stack
+ * pointer to point to the end of the task structure.
+ *
+ * For Interrupts:
+ * If sr7 == 0
+ * Already using a kernel stack, check to see if r30
+ * is already pointing to the per processor interrupt
+ * stack. If it is, call the get_stack_use_r30 macro
+ * to push a pt_regs structure on the stack, and store
+ * registers there. Otherwise, call get_stack_use_cr31
+ * to get a pointer to the base of the interrupt stack
+ * and push a pt_regs structure on that stack.
+ * else
+ * Need to set up a kernel stack, so call the
+ * get_stack_use_cr30 macro to set up a pointer
+ * to the pt_regs structure contained within the
+ * task pointer pointed to by cr30. Set the stack
+ * pointer to point to the end of the task structure.
+ * N.B: We don't use the interrupt stack for the
+ * first interrupt from userland, because signals/
+ * resched's are processed when returning to userland,
+ * and we can sleep in those cases.
+ *
+ * Note that we use shadowed registers for temps until
+ * we can save %r26 and %r29. %r26 is used to preserve
+ * %r8 (a shadowed register) which temporarily contained
+ * either the fault type ("code") or the eirr. We need
+ * to use a non-shadowed register to carry the value over
+ * the rfir in virt_map. We use %r26 since this value winds
+ * up being passed as the argument to either do_cpu_irq_mask
+ * or handle_interruption. %r29 is used to hold a pointer
+ * the register save area, and once again, it needs to
+ * be a non-shadowed register so that it survives the rfir.
+ *
+ * N.B. TASK_SZ_ALGN and PT_SZ_ALGN include space for a stack frame.
+ */
+
+ .macro get_stack_use_cr30
+
+ /* we save the registers in the task struct */
+
+ mfctl %cr30, %r1
+ tophys %r1,%r9
+ LDREG TI_TASK(%r9), %r1 /* thread_info -> task_struct */
+ tophys %r1,%r9
+ ldo TASK_REGS(%r9),%r9
+ STREG %r30, PT_GR30(%r9)
+ STREG %r29,PT_GR29(%r9)
+ STREG %r26,PT_GR26(%r9)
+ copy %r9,%r29
+ mfctl %cr30, %r1
+ ldo THREAD_SZ_ALGN(%r1), %r30
+ .endm
+
+ .macro get_stack_use_r30
+
+ /* we put a struct pt_regs on the stack and save the registers there */
+
+ tophys %r30,%r9
+ STREG %r30,PT_GR30(%r9)
+ ldo PT_SZ_ALGN(%r30),%r30
+ STREG %r29,PT_GR29(%r9)
+ STREG %r26,PT_GR26(%r9)
+ copy %r9,%r29
+ .endm
+
+ .macro rest_stack
+ LDREG PT_GR1(%r29), %r1
+ LDREG PT_GR30(%r29),%r30
+ LDREG PT_GR29(%r29),%r29
+ .endm
+
+ /* default interruption handler
+ * (calls traps.c:handle_interruption) */
+ .macro def code
+ b intr_save
+ ldi \code, %r8
+ .align 32
+ .endm
+
+ /* Interrupt interruption handler
+ * (calls irq.c:do_cpu_irq_mask) */
+ .macro extint code
+ b intr_extint
+ mfsp %sr7,%r16
+ .align 32
+ .endm
+
+ .import os_hpmc, code
+
+ /* HPMC handler */
+ .macro hpmc code
+ nop /* must be a NOP, will be patched later */
+ load32 PA(os_hpmc), %r3
+ bv,n 0(%r3)
+ nop
+ .word 0 /* checksum (will be patched) */
+ .word PA(os_hpmc) /* address of handler */
+ .word 0 /* length of handler */
+ .endm
+
+ /*
+ * Performance Note: Instructions will be moved up into
+ * this part of the code later on, once we are sure
+ * that the tlb miss handlers are close to final form.
+ */
+
+ /* Register definitions for tlb miss handler macros */
+
+ va = r8 /* virtual address for which the trap occured */
+ spc = r24 /* space for which the trap occured */
+
+#ifndef __LP64__
+
+ /*
+ * itlb miss interruption handler (parisc 1.1 - 32 bit)
+ */
+
+ .macro itlb_11 code
+
+ mfctl %pcsq, spc
+ b itlb_miss_11
+ mfctl %pcoq, va
+
+ .align 32
+ .endm
+#endif
+
+ /*
+ * itlb miss interruption handler (parisc 2.0)
+ */
+
+ .macro itlb_20 code
+ mfctl %pcsq, spc
+#ifdef __LP64__
+ b itlb_miss_20w
+#else
+ b itlb_miss_20
+#endif
+ mfctl %pcoq, va
+
+ .align 32
+ .endm
+
+#ifndef __LP64__
+ /*
+ * naitlb miss interruption handler (parisc 1.1 - 32 bit)
+ *
+ * Note: naitlb misses will be treated
+ * as an ordinary itlb miss for now.
+ * However, note that naitlb misses
+ * have the faulting address in the
+ * IOR/ISR.
+ */
+
+ .macro naitlb_11 code
+
+ mfctl %isr,spc
+ b itlb_miss_11
+ mfctl %ior,va
+ /* FIXME: If user causes a naitlb miss, the priv level may not be in
+ * lower bits of va, where the itlb miss handler is expecting them
+ */
+
+ .align 32
+ .endm
+#endif
+
+ /*
+ * naitlb miss interruption handler (parisc 2.0)
+ *
+ * Note: naitlb misses will be treated
+ * as an ordinary itlb miss for now.
+ * However, note that naitlb misses
+ * have the faulting address in the
+ * IOR/ISR.
+ */
+
+ .macro naitlb_20 code
+
+ mfctl %isr,spc
+#ifdef __LP64__
+ b itlb_miss_20w
+#else
+ b itlb_miss_20
+#endif
+ mfctl %ior,va
+ /* FIXME: If user causes a naitlb miss, the priv level may not be in
+ * lower bits of va, where the itlb miss handler is expecting them
+ */
+
+ .align 32
+ .endm
+
+#ifndef __LP64__
+ /*
+ * dtlb miss interruption handler (parisc 1.1 - 32 bit)
+ */
+
+ .macro dtlb_11 code
+
+ mfctl %isr, spc
+ b dtlb_miss_11
+ mfctl %ior, va
+
+ .align 32
+ .endm
+#endif
+
+ /*
+ * dtlb miss interruption handler (parisc 2.0)
+ */
+
+ .macro dtlb_20 code
+
+ mfctl %isr, spc
+#ifdef __LP64__
+ b dtlb_miss_20w
+#else
+ b dtlb_miss_20
+#endif
+ mfctl %ior, va
+
+ .align 32
+ .endm
+
+#ifndef __LP64__
+ /* nadtlb miss interruption handler (parisc 1.1 - 32 bit) */
+
+ .macro nadtlb_11 code
+
+ mfctl %isr,spc
+ b nadtlb_miss_11
+ mfctl %ior,va
+
+ .align 32
+ .endm
+#endif
+
+ /* nadtlb miss interruption handler (parisc 2.0) */
+
+ .macro nadtlb_20 code
+
+ mfctl %isr,spc
+#ifdef __LP64__
+ b nadtlb_miss_20w
+#else
+ b nadtlb_miss_20
+#endif
+ mfctl %ior,va
+
+ .align 32
+ .endm
+
+#ifndef __LP64__
+ /*
+ * dirty bit trap interruption handler (parisc 1.1 - 32 bit)
+ */
+
+ .macro dbit_11 code
+
+ mfctl %isr,spc
+ b dbit_trap_11
+ mfctl %ior,va
+
+ .align 32
+ .endm
+#endif
+
+ /*
+ * dirty bit trap interruption handler (parisc 2.0)
+ */
+
+ .macro dbit_20 code
+
+ mfctl %isr,spc
+#ifdef __LP64__
+ b dbit_trap_20w
+#else
+ b dbit_trap_20
+#endif
+ mfctl %ior,va
+
+ .align 32
+ .endm
+
+ /* The following are simple 32 vs 64 bit instruction
+ * abstractions for the macros */
+ .macro EXTR reg1,start,length,reg2
+#ifdef __LP64__
+ extrd,u \reg1,32+\start,\length,\reg2
+#else
+ extrw,u \reg1,\start,\length,\reg2
+#endif
+ .endm
+
+ .macro DEP reg1,start,length,reg2
+#ifdef __LP64__
+ depd \reg1,32+\start,\length,\reg2
+#else
+ depw \reg1,\start,\length,\reg2
+#endif
+ .endm
+
+ .macro DEPI val,start,length,reg
+#ifdef __LP64__
+ depdi \val,32+\start,\length,\reg
+#else
+ depwi \val,\start,\length,\reg
+#endif
+ .endm
+
+ /* In LP64, the space contains part of the upper 32 bits of the
+ * fault. We have to extract this and place it in the va,
+ * zeroing the corresponding bits in the space register */
+ .macro space_adjust spc,va,tmp
+#ifdef __LP64__
+ extrd,u \spc,63,SPACEID_SHIFT,\tmp
+ depd %r0,63,SPACEID_SHIFT,\spc
+ depd \tmp,31,SPACEID_SHIFT,\va
+#endif
+ .endm
+
+ .import swapper_pg_dir,code
+
+ /* Get the pgd. For faults on space zero (kernel space), this
+ * is simply swapper_pg_dir. For user space faults, the
+ * pgd is stored in %cr25 */
+ .macro get_pgd spc,reg
+ ldil L%PA(swapper_pg_dir),\reg
+ ldo R%PA(swapper_pg_dir)(\reg),\reg
+ or,COND(=) %r0,\spc,%r0
+ mfctl %cr25,\reg
+ .endm
+
+ /*
+ space_check(spc,tmp,fault)
+
+ spc - The space we saw the fault with.
+ tmp - The place to store the current space.
+ fault - Function to call on failure.
+
+ Only allow faults on different spaces from the
+ currently active one if we're the kernel
+
+ */
+ .macro space_check spc,tmp,fault
+ mfsp %sr7,\tmp
+ or,COND(<>) %r0,\spc,%r0 /* user may execute gateway page
+ * as kernel, so defeat the space
+ * check if it is */
+ copy \spc,\tmp
+ or,COND(=) %r0,\tmp,%r0 /* nullify if executing as kernel */
+ cmpb,COND(<>),n \tmp,\spc,\fault
+ .endm
+
+ /* Look up a PTE in a 2-Level scheme (faulting at each
+ * level if the entry isn't present
+ *
+ * NOTE: we use ldw even for LP64, since the short pointers
+ * can address up to 1TB
+ */
+ .macro L2_ptep pmd,pte,index,va,fault
+#if PT_NLEVELS == 3
+ EXTR \va,31-ASM_PMD_SHIFT,ASM_BITS_PER_PMD,\index
+#else
+ EXTR \va,31-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
+#endif
+ DEP %r0,31,PAGE_SHIFT,\pmd /* clear offset */
+ copy %r0,\pte
+ ldw,s \index(\pmd),\pmd
+ bb,>=,n \pmd,_PxD_PRESENT_BIT,\fault
+ DEP %r0,31,PxD_FLAG_SHIFT,\pmd /* clear flags */
+ copy \pmd,%r9
+#ifdef __LP64__
+ shld %r9,PxD_VALUE_SHIFT,\pmd
+#else
+ shlw %r9,PxD_VALUE_SHIFT,\pmd
+#endif
+ EXTR \va,31-PAGE_SHIFT,ASM_BITS_PER_PTE,\index
+ DEP %r0,31,PAGE_SHIFT,\pmd /* clear offset */
+ shladd \index,BITS_PER_PTE_ENTRY,\pmd,\pmd
+ LDREG %r0(\pmd),\pte /* pmd is now pte */
+ bb,>=,n \pte,_PAGE_PRESENT_BIT,\fault
+ .endm
+
+ /* Look up PTE in a 3-Level scheme.
+ *
+ * Here we implement a Hybrid L2/L3 scheme: we allocate the
+ * first pmd adjacent to the pgd. This means that we can
+ * subtract a constant offset to get to it. The pmd and pgd
+ * sizes are arranged so that a single pmd covers 4GB (giving
+ * a full LP64 process access to 8TB) so our lookups are
+ * effectively L2 for the first 4GB of the kernel (i.e. for
+ * all ILP32 processes and all the kernel for machines with
+ * under 4GB of memory) */
+ .macro L3_ptep pgd,pte,index,va,fault
+ extrd,u \va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
+ copy %r0,\pte
+ extrd,u,*= \va,31,32,%r0
+ ldw,s \index(\pgd),\pgd
+ extrd,u,*= \va,31,32,%r0
+ bb,>=,n \pgd,_PxD_PRESENT_BIT,\fault
+ extrd,u,*= \va,31,32,%r0
+ shld \pgd,PxD_VALUE_SHIFT,\index
+ extrd,u,*= \va,31,32,%r0
+ copy \index,\pgd
+ extrd,u,*<> \va,31,32,%r0
+ ldo ASM_PGD_PMD_OFFSET(\pgd),\pgd
+ L2_ptep \pgd,\pte,\index,\va,\fault
+ .endm
+
+ /* Set the _PAGE_ACCESSED bit of the PTE. Be clever and
+ * don't needlessly dirty the cache line if it was already set */
+ .macro update_ptep ptep,pte,tmp,tmp1
+ ldi _PAGE_ACCESSED,\tmp1
+ or \tmp1,\pte,\tmp
+ and,COND(<>) \tmp1,\pte,%r0
+ STREG \tmp,0(\ptep)
+ .endm
+
+ /* Set the dirty bit (and accessed bit). No need to be
+ * clever, this is only used from the dirty fault */
+ .macro update_dirty ptep,pte,tmp
+ ldi _PAGE_ACCESSED|_PAGE_DIRTY,\tmp
+ or \tmp,\pte,\pte
+ STREG \pte,0(\ptep)
+ .endm
+
+ /* Convert the pte and prot to tlb insertion values. How
+ * this happens is quite subtle, read below */
+ .macro make_insert_tlb spc,pte,prot
+ space_to_prot \spc \prot /* create prot id from space */
+ /* The following is the real subtlety. This is depositing
+ * T <-> _PAGE_REFTRAP
+ * D <-> _PAGE_DIRTY
+ * B <-> _PAGE_DMB (memory break)
+ *
+ * Then incredible subtlety: The access rights are
+ * _PAGE_GATEWAY _PAGE_EXEC _PAGE_READ
+ * See 3-14 of the parisc 2.0 manual
+ *
+ * Finally, _PAGE_READ goes in the top bit of PL1 (so we
+ * trigger an access rights trap in user space if the user
+ * tries to read an unreadable page */
+ depd \pte,8,7,\prot
+
+ /* PAGE_USER indicates the page can be read with user privileges,
+ * so deposit X1|11 to PL1|PL2 (remember the upper bit of PL1
+ * contains _PAGE_READ */
+ extrd,u,*= \pte,_PAGE_USER_BIT+32,1,%r0
+ depdi 7,11,3,\prot
+ /* If we're a gateway page, drop PL2 back to zero for promotion
+ * to kernel privilege (so we can execute the page as kernel).
+ * Any privilege promotion page always denys read and write */
+ extrd,u,*= \pte,_PAGE_GATEWAY_BIT+32,1,%r0
+ depd %r0,11,2,\prot /* If Gateway, Set PL2 to 0 */
+
+ /* Get rid of prot bits and convert to page addr for iitlbt */
+
+ depd %r0,63,PAGE_SHIFT,\pte
+ extrd,u \pte,56,32,\pte
+ .endm
+
+ /* Identical macro to make_insert_tlb above, except it
+ * makes the tlb entry for the differently formatted pa11
+ * insertion instructions */
+ .macro make_insert_tlb_11 spc,pte,prot
+ zdep \spc,30,15,\prot
+ dep \pte,8,7,\prot
+ extru,= \pte,_PAGE_NO_CACHE_BIT,1,%r0
+ depi 1,12,1,\prot
+ extru,= \pte,_PAGE_USER_BIT,1,%r0
+ depi 7,11,3,\prot /* Set for user space (1 rsvd for read) */
+ extru,= \pte,_PAGE_GATEWAY_BIT,1,%r0
+ depi 0,11,2,\prot /* If Gateway, Set PL2 to 0 */
+
+ /* Get rid of prot bits and convert to page addr for iitlba */
+
+ depi 0,31,12,\pte
+ extru \pte,24,25,\pte
+
+ .endm
+
+ /* This is for ILP32 PA2.0 only. The TLB insertion needs
+ * to extend into I/O space if the address is 0xfXXXXXXX
+ * so we extend the f's into the top word of the pte in
+ * this case */
+ .macro f_extend pte,tmp
+ extrd,s \pte,42,4,\tmp
+ addi,<> 1,\tmp,%r0
+ extrd,s \pte,63,25,\pte
+ .endm
+
+ /* The alias region is an 8MB aligned 16MB to do clear and
+ * copy user pages at addresses congruent with the user
+ * virtual address.
+ *
+ * To use the alias page, you set %r26 up with the to TLB
+ * entry (identifying the physical page) and %r23 up with
+ * the from tlb entry (or nothing if only a to entry---for
+ * clear_user_page_asm) */
+ .macro do_alias spc,tmp,tmp1,va,pte,prot,fault
+ cmpib,COND(<>),n 0,\spc,\fault
+ ldil L%(TMPALIAS_MAP_START),\tmp
+#if defined(__LP64__) && (TMPALIAS_MAP_START >= 0x80000000)
+ /* on LP64, ldi will sign extend into the upper 32 bits,
+ * which is behaviour we don't want */
+ depdi 0,31,32,\tmp
+#endif
+ copy \va,\tmp1
+ DEPI 0,31,23,\tmp1
+ cmpb,COND(<>),n \tmp,\tmp1,\fault
+ ldi (_PAGE_DIRTY|_PAGE_WRITE|_PAGE_READ),\prot
+ depd,z \prot,8,7,\prot
+ /*
+ * OK, it is in the temp alias region, check whether "from" or "to".
+ * Check "subtle" note in pacache.S re: r23/r26.
+ */
+#ifdef __LP64__
+ extrd,u,*= \va,41,1,%r0
+#else
+ extrw,u,= \va,9,1,%r0
+#endif
+ or,COND(tr) %r23,%r0,\pte
+ or %r26,%r0,\pte
+ .endm
+
+
+ /*
+ * Align fault_vector_20 on 4K boundary so that both
+ * fault_vector_11 and fault_vector_20 are on the
+ * same page. This is only necessary as long as we
+ * write protect the kernel text, which we may stop
+ * doing once we use large page translations to cover
+ * the static part of the kernel address space.
+ */
+
+ .export fault_vector_20
+
+ .text
+
+ .align 4096
+
+fault_vector_20:
+ /* First vector is invalid (0) */
+ .ascii "cows can fly"
+ .byte 0
+ .align 32
+
+ hpmc 1
+ def 2
+ def 3
+ extint 4
+ def 5
+ itlb_20 6
+ def 7
+ def 8
+ def 9
+ def 10
+ def 11
+ def 12
+ def 13
+ def 14
+ dtlb_20 15
+#if 0
+ naitlb_20 16
+#else
+ def 16
+#endif
+ nadtlb_20 17
+ def 18
+ def 19
+ dbit_20 20
+ def 21
+ def 22
+ def 23
+ def 24
+ def 25
+ def 26
+ def 27
+ def 28
+ def 29
+ def 30
+ def 31
+
+#ifndef __LP64__
+
+ .export fault_vector_11
+
+ .align 2048
+
+fault_vector_11:
+ /* First vector is invalid (0) */
+ .ascii "cows can fly"
+ .byte 0
+ .align 32
+
+ hpmc 1
+ def 2
+ def 3
+ extint 4
+ def 5
+ itlb_11 6
+ def 7
+ def 8
+ def 9
+ def 10
+ def 11
+ def 12
+ def 13
+ def 14
+ dtlb_11 15
+#if 0
+ naitlb_11 16
+#else
+ def 16
+#endif
+ nadtlb_11 17
+ def 18
+ def 19
+ dbit_11 20
+ def 21
+ def 22
+ def 23
+ def 24
+ def 25
+ def 26
+ def 27
+ def 28
+ def 29
+ def 30
+ def 31
+
+#endif
+
+ .import handle_interruption,code
+ .import do_cpu_irq_mask,code
+
+ /*
+ * r26 = function to be called
+ * r25 = argument to pass in
+ * r24 = flags for do_fork()
+ *
+ * Kernel threads don't ever return, so they don't need
+ * a true register context. We just save away the arguments
+ * for copy_thread/ret_ to properly set up the child.
+ */
+
+#define CLONE_VM 0x100 /* Must agree with <linux/sched.h> */
+#define CLONE_UNTRACED 0x00800000
+
+ .export __kernel_thread, code
+ .import do_fork
+__kernel_thread:
+ STREG %r2, -RP_OFFSET(%r30)
+
+ copy %r30, %r1
+ ldo PT_SZ_ALGN(%r30),%r30
+#ifdef __LP64__
+ /* Yo, function pointers in wide mode are little structs... -PB */
+ ldd 24(%r26), %r2
+ STREG %r2, PT_GR27(%r1) /* Store childs %dp */
+ ldd 16(%r26), %r26
+
+ STREG %r22, PT_GR22(%r1) /* save r22 (arg5) */
+ copy %r0, %r22 /* user_tid */
+#endif
+ STREG %r26, PT_GR26(%r1) /* Store function & argument for child */
+ STREG %r25, PT_GR25(%r1)
+ ldil L%CLONE_UNTRACED, %r26
+ ldo CLONE_VM(%r26), %r26 /* Force CLONE_VM since only init_mm */
+ or %r26, %r24, %r26 /* will have kernel mappings. */
+ ldi 1, %r25 /* stack_start, signals kernel thread */
+ stw %r0, -52(%r30) /* user_tid */
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+ BL do_fork, %r2
+ copy %r1, %r24 /* pt_regs */
+
+ /* Parent Returns here */
+
+ LDREG -PT_SZ_ALGN-RP_OFFSET(%r30), %r2
+ ldo -PT_SZ_ALGN(%r30), %r30
+ bv %r0(%r2)
+ nop
+
+ /*
+ * Child Returns here
+ *
+ * copy_thread moved args from temp save area set up above
+ * into task save area.
+ */
+
+ .export ret_from_kernel_thread
+ret_from_kernel_thread:
+
+ /* Call schedule_tail first though */
+ BL schedule_tail, %r2
+ nop
+
+ LDREG TI_TASK-THREAD_SZ_ALGN(%r30), %r1
+ LDREG TASK_PT_GR25(%r1), %r26
+#ifdef __LP64__
+ LDREG TASK_PT_GR27(%r1), %r27
+ LDREG TASK_PT_GR22(%r1), %r22
+#endif
+ LDREG TASK_PT_GR26(%r1), %r1
+ ble 0(%sr7, %r1)
+ copy %r31, %r2
+
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+ loadgp /* Thread could have been in a module */
+#endif
+ b sys_exit
+ ldi 0, %r26
+
+ .import sys_execve, code
+ .export __execve, code
+__execve:
+ copy %r2, %r15
+ copy %r30, %r16
+ ldo PT_SZ_ALGN(%r30), %r30
+ STREG %r26, PT_GR26(%r16)
+ STREG %r25, PT_GR25(%r16)
+ STREG %r24, PT_GR24(%r16)
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+ BL sys_execve, %r2
+ copy %r16, %r26
+
+ cmpib,=,n 0,%r28,intr_return /* forward */
+
+ /* yes, this will trap and die. */
+ copy %r15, %r2
+ copy %r16, %r30
+ bv %r0(%r2)
+ nop
+
+ .align 4
+
+ /*
+ * struct task_struct *_switch_to(struct task_struct *prev,
+ * struct task_struct *next)
+ *
+ * switch kernel stacks and return prev */
+ .export _switch_to, code
+_switch_to:
+ STREG %r2, -RP_OFFSET(%r30)
+
+ callee_save
+
+ load32 _switch_to_ret, %r2
+
+ STREG %r2, TASK_PT_KPC(%r26)
+ LDREG TASK_PT_KPC(%r25), %r2
+
+ STREG %r30, TASK_PT_KSP(%r26)
+ LDREG TASK_PT_KSP(%r25), %r30
+ LDREG TASK_THREAD_INFO(%r25), %r25
+ bv %r0(%r2)
+ mtctl %r25,%cr30
+
+_switch_to_ret:
+ mtctl %r0, %cr0 /* Needed for single stepping */
+ callee_rest
+
+ LDREG -RP_OFFSET(%r30), %r2
+ bv %r0(%r2)
+ copy %r26, %r28
+
+ /*
+ * Common rfi return path for interruptions, kernel execve, and
+ * sys_rt_sigreturn (sometimes). The sys_rt_sigreturn syscall will
+ * return via this path if the signal was received when the process
+ * was running; if the process was blocked on a syscall then the
+ * normal syscall_exit path is used. All syscalls for traced
+ * proceses exit via intr_restore.
+ *
+ * XXX If any syscalls that change a processes space id ever exit
+ * this way, then we will need to copy %sr3 in to PT_SR[3..7], and
+ * adjust IASQ[0..1].
+ *
+ * Note that the following code uses a "relied upon translation".
+ * See the parisc ACD for details. The ssm is necessary due to a
+ * PCXT bug.
+ */
+
+ .align 4096
+
+ .export syscall_exit_rfi
+syscall_exit_rfi:
+ mfctl %cr30,%r16
+ LDREG TI_TASK(%r16), %r16 /* thread_info -> task_struct */
+ ldo TASK_REGS(%r16),%r16
+ /* Force iaoq to userspace, as the user has had access to our current
+ * context via sigcontext. Also Filter the PSW for the same reason.
+ */
+ LDREG PT_IAOQ0(%r16),%r19
+ depi 3,31,2,%r19
+ STREG %r19,PT_IAOQ0(%r16)
+ LDREG PT_IAOQ1(%r16),%r19
+ depi 3,31,2,%r19
+ STREG %r19,PT_IAOQ1(%r16)
+ LDREG PT_PSW(%r16),%r19
+ load32 USER_PSW_MASK,%r1
+#ifdef __LP64__
+ load32 USER_PSW_HI_MASK,%r20
+ depd %r20,31,32,%r1
+#endif
+ and %r19,%r1,%r19 /* Mask out bits that user shouldn't play with */
+ load32 USER_PSW,%r1
+ or %r19,%r1,%r19 /* Make sure default USER_PSW bits are set */
+ STREG %r19,PT_PSW(%r16)
+
+ /*
+ * If we aren't being traced, we never saved space registers
+ * (we don't store them in the sigcontext), so set them
+ * to "proper" values now (otherwise we'll wind up restoring
+ * whatever was last stored in the task structure, which might
+ * be inconsistent if an interrupt occured while on the gateway
+ * page) Note that we may be "trashing" values the user put in
+ * them, but we don't support the the user changing them.
+ */
+
+ STREG %r0,PT_SR2(%r16)
+ mfsp %sr3,%r19
+ STREG %r19,PT_SR0(%r16)
+ STREG %r19,PT_SR1(%r16)
+ STREG %r19,PT_SR3(%r16)
+ STREG %r19,PT_SR4(%r16)
+ STREG %r19,PT_SR5(%r16)
+ STREG %r19,PT_SR6(%r16)
+ STREG %r19,PT_SR7(%r16)
+
+intr_return:
+ /* NOTE: Need to enable interrupts incase we schedule. */
+ ssm PSW_SM_I, %r0
+
+ /* Check for software interrupts */
+
+ .import irq_stat,data
+
+ load32 irq_stat,%r19
+#ifdef CONFIG_SMP
+ mfctl %cr30,%r1
+ ldw TI_CPU(%r1),%r1 /* get cpu # - int */
+ /* shift left ____cacheline_aligned (aka L1_CACHE_BYTES) amount
+ ** irq_stat[] is defined using ____cacheline_aligned.
+ */
+#ifdef __LP64__
+ shld %r1, 6, %r20
+#else
+ shlw %r1, 5, %r20
+#endif
+ add %r19,%r20,%r19 /* now have &irq_stat[smp_processor_id()] */
+#endif /* CONFIG_SMP */
+
+ LDREG IRQSTAT_SIRQ_PEND(%r19),%r20 /* hardirq.h: unsigned long */
+ cmpib,<>,n 0,%r20,intr_do_softirq /* forward */
+
+intr_check_resched:
+
+ /* check for reschedule */
+ mfctl %cr30,%r1
+ LDREG TI_FLAGS(%r1),%r19 /* sched.h: TIF_NEED_RESCHED */
+ bb,<,n %r19,31-TIF_NEED_RESCHED,intr_do_resched /* forward */
+
+intr_check_sig:
+ /* As above */
+ mfctl %cr30,%r1
+ LDREG TI_FLAGS(%r1),%r19 /* sched.h: TIF_SIGPENDING */
+ bb,<,n %r19, 31-TIF_SIGPENDING, intr_do_signal /* forward */
+
+intr_restore:
+ copy %r16,%r29
+ ldo PT_FR31(%r29),%r1
+ rest_fp %r1
+ rest_general %r29
+
+ /* Create a "relied upon translation" PA 2.0 Arch. F-5 */
+ ssm 0,%r0
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ tophys_r1 %r29
+ rsm (PSW_SM_Q|PSW_SM_P|PSW_SM_D|PSW_SM_I),%r0
+
+ /* Restore space id's and special cr's from PT_REGS
+ * structure pointed to by r29 */
+ rest_specials %r29
+
+ /* Important: Note that rest_stack restores r29
+ * last (we are using it)! It also restores r1 and r30. */
+ rest_stack
+
+ rfi
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ .import do_softirq,code
+intr_do_softirq:
+ bl do_softirq,%r2
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#else
+ nop
+#endif
+ b intr_check_resched
+ nop
+
+ .import schedule,code
+intr_do_resched:
+ /* Only do reschedule if we are returning to user space */
+ LDREG PT_IASQ0(%r16), %r20
+ CMPIB= 0,%r20,intr_restore /* backward */
+ nop
+ LDREG PT_IASQ1(%r16), %r20
+ CMPIB= 0,%r20,intr_restore /* backward */
+ nop
+
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+
+ ldil L%intr_check_sig, %r2
+ b schedule
+ ldo R%intr_check_sig(%r2), %r2
+
+
+ .import do_signal,code
+intr_do_signal:
+ /*
+ This check is critical to having LWS
+ working. The IASQ is zero on the gateway
+ page and we cannot deliver any signals until
+ we get off the gateway page.
+
+ Only do signals if we are returning to user space
+ */
+ LDREG PT_IASQ0(%r16), %r20
+ CMPIB= 0,%r20,intr_restore /* backward */
+ nop
+ LDREG PT_IASQ1(%r16), %r20
+ CMPIB= 0,%r20,intr_restore /* backward */
+ nop
+
+ copy %r0, %r24 /* unsigned long in_syscall */
+ copy %r16, %r25 /* struct pt_regs *regs */
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+
+ BL do_signal,%r2
+ copy %r0, %r26 /* sigset_t *oldset = NULL */
+
+ b intr_check_sig
+ nop
+
+ /*
+ * External interrupts.
+ */
+
+intr_extint:
+ CMPIB=,n 0,%r16,1f
+ get_stack_use_cr30
+ b,n 3f
+
+1:
+#if 0 /* Interrupt Stack support not working yet! */
+ mfctl %cr31,%r1
+ copy %r30,%r17
+ /* FIXME! depi below has hardcoded idea of interrupt stack size (32k)*/
+#ifdef __LP64__
+ depdi 0,63,15,%r17
+#else
+ depi 0,31,15,%r17
+#endif
+ CMPB=,n %r1,%r17,2f
+ get_stack_use_cr31
+ b,n 3f
+#endif
+2:
+ get_stack_use_r30
+
+3:
+ save_specials %r29
+ virt_map
+ save_general %r29
+
+ ldo PT_FR0(%r29), %r24
+ save_fp %r24
+
+ loadgp
+
+ copy %r29, %r26 /* arg0 is pt_regs */
+ copy %r29, %r16 /* save pt_regs */
+
+ ldil L%intr_return, %r2
+
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+
+ b do_cpu_irq_mask
+ ldo R%intr_return(%r2), %r2 /* return to intr_return, not here */
+
+
+ /* Generic interruptions (illegal insn, unaligned, page fault, etc) */
+
+ .export intr_save, code /* for os_hpmc */
+
+intr_save:
+ mfsp %sr7,%r16
+ CMPIB=,n 0,%r16,1f
+ get_stack_use_cr30
+ b 2f
+ copy %r8,%r26
+
+1:
+ get_stack_use_r30
+ copy %r8,%r26
+
+2:
+ save_specials %r29
+
+ /* If this trap is a itlb miss, skip saving/adjusting isr/ior */
+
+ /*
+ * FIXME: 1) Use a #define for the hardwired "6" below (and in
+ * traps.c.
+ * 2) Once we start executing code above 4 Gb, we need
+ * to adjust iasq/iaoq here in the same way we
+ * adjust isr/ior below.
+ */
+
+ CMPIB=,n 6,%r26,skip_save_ior
+
+ /* save_specials left ipsw value in r8 for us to test */
+
+ mfctl %cr20, %r16 /* isr */
+ mfctl %cr21, %r17 /* ior */
+
+#ifdef __LP64__
+ /*
+ * If the interrupted code was running with W bit off (32 bit),
+ * clear the b bits (bits 0 & 1) in the ior.
+ */
+ extrd,u,*<> %r8,PSW_W_BIT,1,%r0
+ depdi 0,1,2,%r17
+
+ /*
+ * FIXME: This code has hardwired assumptions about the split
+ * between space bits and offset bits. This will change
+ * when we allow alternate page sizes.
+ */
+
+ /* adjust isr/ior. */
+
+ extrd,u %r16,63,7,%r1 /* get high bits from isr for ior */
+ depd %r1,31,7,%r17 /* deposit them into ior */
+ depdi 0,63,7,%r16 /* clear them from isr */
+#endif
+ STREG %r16, PT_ISR(%r29)
+ STREG %r17, PT_IOR(%r29)
+
+
+skip_save_ior:
+ virt_map
+ save_general %r29
+
+ ldo PT_FR0(%r29), %r25
+ save_fp %r25
+
+ loadgp
+
+ copy %r29, %r25 /* arg1 is pt_regs */
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+
+ ldil L%intr_check_sig, %r2
+ copy %r25, %r16 /* save pt_regs */
+
+ b handle_interruption
+ ldo R%intr_check_sig(%r2), %r2
+
+
+ /*
+ * Note for all tlb miss handlers:
+ *
+ * cr24 contains a pointer to the kernel address space
+ * page directory.
+ *
+ * cr25 contains a pointer to the current user address
+ * space page directory.
+ *
+ * sr3 will contain the space id of the user address space
+ * of the current running thread while that thread is
+ * running in the kernel.
+ */
+
+ /*
+ * register number allocations. Note that these are all
+ * in the shadowed registers
+ */
+
+ t0 = r1 /* temporary register 0 */
+ va = r8 /* virtual address for which the trap occured */
+ t1 = r9 /* temporary register 1 */
+ pte = r16 /* pte/phys page # */
+ prot = r17 /* prot bits */
+ spc = r24 /* space for which the trap occured */
+ ptp = r25 /* page directory/page table pointer */
+
+#ifdef __LP64__
+
+dtlb_miss_20w:
+ space_adjust spc,va,t0
+ get_pgd spc,ptp
+ space_check spc,t0,dtlb_fault
+
+ L3_ptep ptp,pte,t0,va,dtlb_check_alias_20w
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb spc,pte,prot
+
+ idtlbt pte,prot
+
+ rfir
+ nop
+
+dtlb_check_alias_20w:
+ do_alias spc,t0,t1,va,pte,prot,dtlb_fault
+
+ idtlbt pte,prot
+
+ rfir
+ nop
+
+nadtlb_miss_20w:
+ space_adjust spc,va,t0
+ get_pgd spc,ptp
+ space_check spc,t0,nadtlb_fault
+
+ L3_ptep ptp,pte,t0,va,nadtlb_check_flush_20w
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb spc,pte,prot
+
+ idtlbt pte,prot
+
+ rfir
+ nop
+
+nadtlb_check_flush_20w:
+ bb,>=,n pte,_PAGE_FLUSH_BIT,nadtlb_emulate
+
+ /* Insert a "flush only" translation */
+
+ depdi,z 7,7,3,prot
+ depdi 1,10,1,prot
+
+ /* Get rid of prot bits and convert to page addr for idtlbt */
+
+ depdi 0,63,12,pte
+ extrd,u pte,56,52,pte
+ idtlbt pte,prot
+
+ rfir
+ nop
+
+#else
+
+dtlb_miss_11:
+ get_pgd spc,ptp
+
+ space_check spc,t0,dtlb_fault
+
+ L2_ptep ptp,pte,t0,va,dtlb_check_alias_11
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb_11 spc,pte,prot
+
+ mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
+ mtsp spc,%sr1
+
+ idtlba pte,(%sr1,va)
+ idtlbp prot,(%sr1,va)
+
+ mtsp t0, %sr1 /* Restore sr1 */
+
+ rfir
+ nop
+
+dtlb_check_alias_11:
+
+ /* Check to see if fault is in the temporary alias region */
+
+ cmpib,<>,n 0,spc,dtlb_fault /* forward */
+ ldil L%(TMPALIAS_MAP_START),t0
+ copy va,t1
+ depwi 0,31,23,t1
+ cmpb,<>,n t0,t1,dtlb_fault /* forward */
+ ldi (_PAGE_DIRTY|_PAGE_WRITE|_PAGE_READ),prot
+ depw,z prot,8,7,prot
+
+ /*
+ * OK, it is in the temp alias region, check whether "from" or "to".
+ * Check "subtle" note in pacache.S re: r23/r26.
+ */
+
+ extrw,u,= va,9,1,r0
+ or,tr %r23,%r0,pte /* If "from" use "from" page */
+ or %r26,%r0,pte /* else "to", use "to" page */
+
+ idtlba pte,(va)
+ idtlbp prot,(va)
+
+ rfir
+ nop
+
+nadtlb_miss_11:
+ get_pgd spc,ptp
+
+ space_check spc,t0,nadtlb_fault
+
+ L2_ptep ptp,pte,t0,va,nadtlb_check_flush_11
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb_11 spc,pte,prot
+
+
+ mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
+ mtsp spc,%sr1
+
+ idtlba pte,(%sr1,va)
+ idtlbp prot,(%sr1,va)
+
+ mtsp t0, %sr1 /* Restore sr1 */
+
+ rfir
+ nop
+
+nadtlb_check_flush_11:
+ bb,>=,n pte,_PAGE_FLUSH_BIT,nadtlb_emulate
+
+ /* Insert a "flush only" translation */
+
+ zdepi 7,7,3,prot
+ depi 1,10,1,prot
+
+ /* Get rid of prot bits and convert to page addr for idtlba */
+
+ depi 0,31,12,pte
+ extru pte,24,25,pte
+
+ mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
+ mtsp spc,%sr1
+
+ idtlba pte,(%sr1,va)
+ idtlbp prot,(%sr1,va)
+
+ mtsp t0, %sr1 /* Restore sr1 */
+
+ rfir
+ nop
+
+dtlb_miss_20:
+ space_adjust spc,va,t0
+ get_pgd spc,ptp
+ space_check spc,t0,dtlb_fault
+
+ L2_ptep ptp,pte,t0,va,dtlb_check_alias_20
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb spc,pte,prot
+
+ f_extend pte,t0
+
+ idtlbt pte,prot
+
+ rfir
+ nop
+
+dtlb_check_alias_20:
+ do_alias spc,t0,t1,va,pte,prot,dtlb_fault
+
+ idtlbt pte,prot
+
+ rfir
+ nop
+
+nadtlb_miss_20:
+ get_pgd spc,ptp
+
+ space_check spc,t0,nadtlb_fault
+
+ L2_ptep ptp,pte,t0,va,nadtlb_check_flush_20
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb spc,pte,prot
+
+ f_extend pte,t0
+
+ idtlbt pte,prot
+
+ rfir
+ nop
+
+nadtlb_check_flush_20:
+ bb,>=,n pte,_PAGE_FLUSH_BIT,nadtlb_emulate
+
+ /* Insert a "flush only" translation */
+
+ depdi,z 7,7,3,prot
+ depdi 1,10,1,prot
+
+ /* Get rid of prot bits and convert to page addr for idtlbt */
+
+ depdi 0,63,12,pte
+ extrd,u pte,56,32,pte
+ idtlbt pte,prot
+
+ rfir
+ nop
+#endif
+
+nadtlb_emulate:
+
+ /*
+ * Non access misses can be caused by fdc,fic,pdc,lpa,probe and
+ * probei instructions. We don't want to fault for these
+ * instructions (not only does it not make sense, it can cause
+ * deadlocks, since some flushes are done with the mmap
+ * semaphore held). If the translation doesn't exist, we can't
+ * insert a translation, so have to emulate the side effects
+ * of the instruction. Since we don't insert a translation
+ * we can get a lot of faults during a flush loop, so it makes
+ * sense to try to do it here with minimum overhead. We only
+ * emulate fdc,fic,pdc,probew,prober instructions whose base
+ * and index registers are not shadowed. We defer everything
+ * else to the "slow" path.
+ */
+
+ mfctl %cr19,%r9 /* Get iir */
+
+ /* PA 2.0 Arch Ref. Book pg 382 has a good description of the insn bits.
+ Checks for fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw */
+
+ /* Checks for fdc,fdce,pdc,"fic,4f" only */
+ ldi 0x280,%r16
+ and %r9,%r16,%r17
+ cmpb,<>,n %r16,%r17,nadtlb_probe_check
+ bb,>=,n %r9,26,nadtlb_nullify /* m bit not set, just nullify */
+ BL get_register,%r25
+ extrw,u %r9,15,5,%r8 /* Get index register # */
+ CMPIB=,n -1,%r1,nadtlb_fault /* have to use slow path */
+ copy %r1,%r24
+ BL get_register,%r25
+ extrw,u %r9,10,5,%r8 /* Get base register # */
+ CMPIB=,n -1,%r1,nadtlb_fault /* have to use slow path */
+ BL set_register,%r25
+ add,l %r1,%r24,%r1 /* doesn't affect c/b bits */
+
+nadtlb_nullify:
+ mfctl %cr22,%r8 /* Get ipsw */
+ ldil L%PSW_N,%r9
+ or %r8,%r9,%r8 /* Set PSW_N */
+ mtctl %r8,%cr22
+
+ rfir
+ nop
+
+ /*
+ When there is no translation for the probe address then we
+ must nullify the insn and return zero in the target regsiter.
+ This will indicate to the calling code that it does not have
+ write/read privileges to this address.
+
+ This should technically work for prober and probew in PA 1.1,
+ and also probe,r and probe,w in PA 2.0
+
+ WARNING: USE ONLY NON-SHADOW REGISTERS WITH PROBE INSN!
+ THE SLOW-PATH EMULATION HAS NOT BEEN WRITTEN YET.
+
+ */
+nadtlb_probe_check:
+ ldi 0x80,%r16
+ and %r9,%r16,%r17
+ cmpb,<>,n %r16,%r17,nadtlb_fault /* Must be probe,[rw]*/
+ BL get_register,%r25 /* Find the target register */
+ extrw,u %r9,31,5,%r8 /* Get target register */
+ CMPIB=,n -1,%r1,nadtlb_fault /* have to use slow path */
+ BL set_register,%r25
+ copy %r0,%r1 /* Write zero to target register */
+ b nadtlb_nullify /* Nullify return insn */
+ nop
+
+
+#ifdef __LP64__
+itlb_miss_20w:
+
+ /*
+ * I miss is a little different, since we allow users to fault
+ * on the gateway page which is in the kernel address space.
+ */
+
+ space_adjust spc,va,t0
+ get_pgd spc,ptp
+ space_check spc,t0,itlb_fault
+
+ L3_ptep ptp,pte,t0,va,itlb_fault
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb spc,pte,prot
+
+ iitlbt pte,prot
+
+ rfir
+ nop
+
+#else
+
+itlb_miss_11:
+ get_pgd spc,ptp
+
+ space_check spc,t0,itlb_fault
+
+ L2_ptep ptp,pte,t0,va,itlb_fault
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb_11 spc,pte,prot
+
+ mfsp %sr1,t0 /* Save sr1 so we can use it in tlb inserts */
+ mtsp spc,%sr1
+
+ iitlba pte,(%sr1,va)
+ iitlbp prot,(%sr1,va)
+
+ mtsp t0, %sr1 /* Restore sr1 */
+
+ rfir
+ nop
+
+itlb_miss_20:
+ get_pgd spc,ptp
+
+ space_check spc,t0,itlb_fault
+
+ L2_ptep ptp,pte,t0,va,itlb_fault
+
+ update_ptep ptp,pte,t0,t1
+
+ make_insert_tlb spc,pte,prot
+
+ f_extend pte,t0
+
+ iitlbt pte,prot
+
+ rfir
+ nop
+
+#endif
+
+#ifdef __LP64__
+
+dbit_trap_20w:
+ space_adjust spc,va,t0
+ get_pgd spc,ptp
+ space_check spc,t0,dbit_fault
+
+ L3_ptep ptp,pte,t0,va,dbit_fault
+
+#ifdef CONFIG_SMP
+ CMPIB=,n 0,spc,dbit_nolock_20w
+ load32 PA(pa_dbit_lock),t0
+
+dbit_spin_20w:
+ ldcw 0(t0),t1
+ cmpib,= 0,t1,dbit_spin_20w
+ nop
+
+dbit_nolock_20w:
+#endif
+ update_dirty ptp,pte,t1
+
+ make_insert_tlb spc,pte,prot
+
+ idtlbt pte,prot
+#ifdef CONFIG_SMP
+ CMPIB=,n 0,spc,dbit_nounlock_20w
+ ldi 1,t1
+ stw t1,0(t0)
+
+dbit_nounlock_20w:
+#endif
+
+ rfir
+ nop
+#else
+
+dbit_trap_11:
+
+ get_pgd spc,ptp
+
+ space_check spc,t0,dbit_fault
+
+ L2_ptep ptp,pte,t0,va,dbit_fault
+
+#ifdef CONFIG_SMP
+ CMPIB=,n 0,spc,dbit_nolock_11
+ load32 PA(pa_dbit_lock),t0
+
+dbit_spin_11:
+ ldcw 0(t0),t1
+ cmpib,= 0,t1,dbit_spin_11
+ nop
+
+dbit_nolock_11:
+#endif
+ update_dirty ptp,pte,t1
+
+ make_insert_tlb_11 spc,pte,prot
+
+ mfsp %sr1,t1 /* Save sr1 so we can use it in tlb inserts */
+ mtsp spc,%sr1
+
+ idtlba pte,(%sr1,va)
+ idtlbp prot,(%sr1,va)
+
+ mtsp t1, %sr1 /* Restore sr1 */
+#ifdef CONFIG_SMP
+ CMPIB=,n 0,spc,dbit_nounlock_11
+ ldi 1,t1
+ stw t1,0(t0)
+
+dbit_nounlock_11:
+#endif
+
+ rfir
+ nop
+
+dbit_trap_20:
+ get_pgd spc,ptp
+
+ space_check spc,t0,dbit_fault
+
+ L2_ptep ptp,pte,t0,va,dbit_fault
+
+#ifdef CONFIG_SMP
+ CMPIB=,n 0,spc,dbit_nolock_20
+ load32 PA(pa_dbit_lock),t0
+
+dbit_spin_20:
+ ldcw 0(t0),t1
+ cmpib,= 0,t1,dbit_spin_20
+ nop
+
+dbit_nolock_20:
+#endif
+ update_dirty ptp,pte,t1
+
+ make_insert_tlb spc,pte,prot
+
+ f_extend pte,t1
+
+ idtlbt pte,prot
+
+#ifdef CONFIG_SMP
+ CMPIB=,n 0,spc,dbit_nounlock_20
+ ldi 1,t1
+ stw t1,0(t0)
+
+dbit_nounlock_20:
+#endif
+
+ rfir
+ nop
+#endif
+
+ .import handle_interruption,code
+
+kernel_bad_space:
+ b intr_save
+ ldi 31,%r8 /* Use an unused code */
+
+dbit_fault:
+ b intr_save
+ ldi 20,%r8
+
+itlb_fault:
+ b intr_save
+ ldi 6,%r8
+
+nadtlb_fault:
+ b intr_save
+ ldi 17,%r8
+
+dtlb_fault:
+ b intr_save
+ ldi 15,%r8
+
+ /* Register saving semantics for system calls:
+
+ %r1 clobbered by system call macro in userspace
+ %r2 saved in PT_REGS by gateway page
+ %r3 - %r18 preserved by C code (saved by signal code)
+ %r19 - %r20 saved in PT_REGS by gateway page
+ %r21 - %r22 non-standard syscall args
+ stored in kernel stack by gateway page
+ %r23 - %r26 arg3-arg0, saved in PT_REGS by gateway page
+ %r27 - %r30 saved in PT_REGS by gateway page
+ %r31 syscall return pointer
+ */
+
+ /* Floating point registers (FIXME: what do we do with these?)
+
+ %fr0 - %fr3 status/exception, not preserved
+ %fr4 - %fr7 arguments
+ %fr8 - %fr11 not preserved by C code
+ %fr12 - %fr21 preserved by C code
+ %fr22 - %fr31 not preserved by C code
+ */
+
+ .macro reg_save regs
+ STREG %r3, PT_GR3(\regs)
+ STREG %r4, PT_GR4(\regs)
+ STREG %r5, PT_GR5(\regs)
+ STREG %r6, PT_GR6(\regs)
+ STREG %r7, PT_GR7(\regs)
+ STREG %r8, PT_GR8(\regs)
+ STREG %r9, PT_GR9(\regs)
+ STREG %r10,PT_GR10(\regs)
+ STREG %r11,PT_GR11(\regs)
+ STREG %r12,PT_GR12(\regs)
+ STREG %r13,PT_GR13(\regs)
+ STREG %r14,PT_GR14(\regs)
+ STREG %r15,PT_GR15(\regs)
+ STREG %r16,PT_GR16(\regs)
+ STREG %r17,PT_GR17(\regs)
+ STREG %r18,PT_GR18(\regs)
+ .endm
+
+ .macro reg_restore regs
+ LDREG PT_GR3(\regs), %r3
+ LDREG PT_GR4(\regs), %r4
+ LDREG PT_GR5(\regs), %r5
+ LDREG PT_GR6(\regs), %r6
+ LDREG PT_GR7(\regs), %r7
+ LDREG PT_GR8(\regs), %r8
+ LDREG PT_GR9(\regs), %r9
+ LDREG PT_GR10(\regs),%r10
+ LDREG PT_GR11(\regs),%r11
+ LDREG PT_GR12(\regs),%r12
+ LDREG PT_GR13(\regs),%r13
+ LDREG PT_GR14(\regs),%r14
+ LDREG PT_GR15(\regs),%r15
+ LDREG PT_GR16(\regs),%r16
+ LDREG PT_GR17(\regs),%r17
+ LDREG PT_GR18(\regs),%r18
+ .endm
+
+ .export sys_fork_wrapper
+ .export child_return
+sys_fork_wrapper:
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
+ ldo TASK_REGS(%r1),%r1
+ reg_save %r1
+ mfctl %cr27, %r3
+ STREG %r3, PT_CR27(%r1)
+
+ STREG %r2,-RP_OFFSET(%r30)
+ ldo FRAME_SIZE(%r30),%r30
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+
+ /* These are call-clobbered registers and therefore
+ also syscall-clobbered (we hope). */
+ STREG %r2,PT_GR19(%r1) /* save for child */
+ STREG %r30,PT_GR21(%r1)
+
+ LDREG PT_GR30(%r1),%r25
+ copy %r1,%r24
+ BL sys_clone,%r2
+ ldi SIGCHLD,%r26
+
+ LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2
+wrapper_exit:
+ ldo -FRAME_SIZE(%r30),%r30 /* get the stackframe */
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1),%r1 /* get pt regs */
+
+ LDREG PT_CR27(%r1), %r3
+ mtctl %r3, %cr27
+ reg_restore %r1
+
+ /* strace expects syscall # to be preserved in r20 */
+ ldi __NR_fork,%r20
+ bv %r0(%r2)
+ STREG %r20,PT_GR20(%r1)
+
+ /* Set the return value for the child */
+child_return:
+ BL schedule_tail, %r2
+ nop
+
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE-FRAME_SIZE(%r30), %r1
+ LDREG TASK_PT_GR19(%r1),%r2
+ b wrapper_exit
+ copy %r0,%r28
+
+
+ .export sys_clone_wrapper
+sys_clone_wrapper:
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1),%r1 /* get pt regs */
+ reg_save %r1
+ mfctl %cr27, %r3
+ STREG %r3, PT_CR27(%r1)
+
+ STREG %r2,-RP_OFFSET(%r30)
+ ldo FRAME_SIZE(%r30),%r30
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+
+ STREG %r2,PT_GR19(%r1) /* save for child */
+ STREG %r30,PT_GR21(%r1)
+ BL sys_clone,%r2
+ copy %r1,%r24
+
+ b wrapper_exit
+ LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2
+
+ .export sys_vfork_wrapper
+sys_vfork_wrapper:
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1),%r1 /* get pt regs */
+ reg_save %r1
+ mfctl %cr27, %r3
+ STREG %r3, PT_CR27(%r1)
+
+ STREG %r2,-RP_OFFSET(%r30)
+ ldo FRAME_SIZE(%r30),%r30
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+
+ STREG %r2,PT_GR19(%r1) /* save for child */
+ STREG %r30,PT_GR21(%r1)
+
+ BL sys_vfork,%r2
+ copy %r1,%r26
+
+ b wrapper_exit
+ LDREG -RP_OFFSET-FRAME_SIZE(%r30),%r2
+
+
+ .macro execve_wrapper execve
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1),%r1 /* get pt regs */
+
+ /*
+ * Do we need to save/restore r3-r18 here?
+ * I don't think so. why would new thread need old
+ * threads registers?
+ */
+
+ /* %arg0 - %arg3 are already saved for us. */
+
+ STREG %r2,-RP_OFFSET(%r30)
+ ldo FRAME_SIZE(%r30),%r30
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+ bl \execve,%r2
+ copy %r1,%arg0
+
+ ldo -FRAME_SIZE(%r30),%r30
+ LDREG -RP_OFFSET(%r30),%r2
+
+ /* If exec succeeded we need to load the args */
+
+ ldo -1024(%r0),%r1
+ cmpb,>>= %r28,%r1,error_\execve
+ copy %r2,%r19
+
+error_\execve:
+ bv %r0(%r19)
+ nop
+ .endm
+
+ .export sys_execve_wrapper
+ .import sys_execve
+
+sys_execve_wrapper:
+ execve_wrapper sys_execve
+
+#ifdef __LP64__
+ .export sys32_execve_wrapper
+ .import sys32_execve
+
+sys32_execve_wrapper:
+ execve_wrapper sys32_execve
+#endif
+
+ .export sys_rt_sigreturn_wrapper
+sys_rt_sigreturn_wrapper:
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26
+ ldo TASK_REGS(%r26),%r26 /* get pt regs */
+ /* Don't save regs, we are going to restore them from sigcontext. */
+ STREG %r2, -RP_OFFSET(%r30)
+#ifdef __LP64__
+ ldo FRAME_SIZE(%r30), %r30
+ BL sys_rt_sigreturn,%r2
+ ldo -16(%r30),%r29 /* Reference param save area */
+#else
+ BL sys_rt_sigreturn,%r2
+ ldo FRAME_SIZE(%r30), %r30
+#endif
+
+ ldo -FRAME_SIZE(%r30), %r30
+ LDREG -RP_OFFSET(%r30), %r2
+
+ /* FIXME: I think we need to restore a few more things here. */
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1),%r1 /* get pt regs */
+ reg_restore %r1
+
+ /* If the signal was received while the process was blocked on a
+ * syscall, then r2 will take us to syscall_exit; otherwise r2 will
+ * take us to syscall_exit_rfi and on to intr_return.
+ */
+ bv %r0(%r2)
+ LDREG PT_GR28(%r1),%r28 /* reload original r28 for syscall_exit */
+
+ .export sys_sigaltstack_wrapper
+sys_sigaltstack_wrapper:
+ /* Get the user stack pointer */
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1),%r24 /* get pt regs */
+ LDREG TASK_PT_GR30(%r24),%r24
+ STREG %r2, -RP_OFFSET(%r30)
+#ifdef __LP64__
+ ldo FRAME_SIZE(%r30), %r30
+ b,l do_sigaltstack,%r2
+ ldo -16(%r30),%r29 /* Reference param save area */
+#else
+ bl do_sigaltstack,%r2
+ ldo FRAME_SIZE(%r30), %r30
+#endif
+
+ ldo -FRAME_SIZE(%r30), %r30
+ LDREG -RP_OFFSET(%r30), %r2
+ bv %r0(%r2)
+ nop
+
+#ifdef __LP64__
+ .export sys32_sigaltstack_wrapper
+sys32_sigaltstack_wrapper:
+ /* Get the user stack pointer */
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r24
+ LDREG TASK_PT_GR30(%r24),%r24
+ STREG %r2, -RP_OFFSET(%r30)
+ ldo FRAME_SIZE(%r30), %r30
+ b,l do_sigaltstack32,%r2
+ ldo -16(%r30),%r29 /* Reference param save area */
+
+ ldo -FRAME_SIZE(%r30), %r30
+ LDREG -RP_OFFSET(%r30), %r2
+ bv %r0(%r2)
+ nop
+#endif
+
+ .export sys_rt_sigsuspend_wrapper
+sys_rt_sigsuspend_wrapper:
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
+ ldo TASK_REGS(%r1),%r24
+ reg_save %r24
+
+ STREG %r2, -RP_OFFSET(%r30)
+#ifdef __LP64__
+ ldo FRAME_SIZE(%r30), %r30
+ b,l sys_rt_sigsuspend,%r2
+ ldo -16(%r30),%r29 /* Reference param save area */
+#else
+ bl sys_rt_sigsuspend,%r2
+ ldo FRAME_SIZE(%r30), %r30
+#endif
+
+ ldo -FRAME_SIZE(%r30), %r30
+ LDREG -RP_OFFSET(%r30), %r2
+
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
+ ldo TASK_REGS(%r1),%r1
+ reg_restore %r1
+
+ bv %r0(%r2)
+ nop
+
+ .export syscall_exit
+syscall_exit:
+
+ /* NOTE: HP-UX syscalls also come through here
+ * after hpux_syscall_exit fixes up return
+ * values. */
+
+ /* NOTE: Not all syscalls exit this way. rt_sigreturn will exit
+ * via syscall_exit_rfi if the signal was received while the process
+ * was running.
+ */
+
+ /* save return value now */
+
+ mfctl %cr30, %r1
+ LDREG TI_TASK(%r1),%r1
+ STREG %r28,TASK_PT_GR28(%r1)
+
+#ifdef CONFIG_HPUX
+
+/* <linux/personality.h> cannot be easily included */
+#define PER_HPUX 0x10
+ LDREG TASK_PERSONALITY(%r1),%r19
+
+ /* We can't use "CMPIB<> PER_HPUX" since "im5" field is sign extended */
+ ldo -PER_HPUX(%r19), %r19
+ CMPIB<>,n 0,%r19,1f
+
+ /* Save other hpux returns if personality is PER_HPUX */
+ STREG %r22,TASK_PT_GR22(%r1)
+ STREG %r29,TASK_PT_GR29(%r1)
+1:
+
+#endif /* CONFIG_HPUX */
+
+ /* Seems to me that dp could be wrong here, if the syscall involved
+ * calling a module, and nothing got round to restoring dp on return.
+ */
+ loadgp
+
+syscall_check_bh:
+
+ /* Check for software interrupts */
+
+ .import irq_stat,data
+
+ load32 irq_stat,%r19
+
+#ifdef CONFIG_SMP
+ /* sched.h: int processor */
+ /* %r26 is used as scratch register to index into irq_stat[] */
+ ldw TI_CPU-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26 /* cpu # */
+
+ /* shift left ____cacheline_aligned (aka L1_CACHE_BYTES) bits */
+#ifdef __LP64__
+ shld %r26, 6, %r20
+#else
+ shlw %r26, 5, %r20
+#endif
+ add %r19,%r20,%r19 /* now have &irq_stat[smp_processor_id()] */
+#endif /* CONFIG_SMP */
+
+ LDREG IRQSTAT_SIRQ_PEND(%r19),%r20 /* hardirq.h: unsigned long */
+ cmpib,<>,n 0,%r20,syscall_do_softirq /* forward */
+
+syscall_check_resched:
+
+ /* check for reschedule */
+
+ LDREG TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19 /* long */
+ bb,<,n %r19, 31-TIF_NEED_RESCHED, syscall_do_resched /* forward */
+
+syscall_check_sig:
+ LDREG TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19 /* get ti flags */
+ bb,<,n %r19, 31-TIF_SIGPENDING, syscall_do_signal /* forward */
+
+syscall_restore:
+ /* Are we being ptraced? */
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+
+ LDREG TASK_PTRACE(%r1), %r19
+ bb,< %r19,31,syscall_restore_rfi
+ nop
+
+ ldo TASK_PT_FR31(%r1),%r19 /* reload fpregs */
+ rest_fp %r19
+
+ LDREG TASK_PT_SAR(%r1),%r19 /* restore SAR */
+ mtsar %r19
+
+ LDREG TASK_PT_GR2(%r1),%r2 /* restore user rp */
+ LDREG TASK_PT_GR19(%r1),%r19
+ LDREG TASK_PT_GR20(%r1),%r20
+ LDREG TASK_PT_GR21(%r1),%r21
+ LDREG TASK_PT_GR22(%r1),%r22
+ LDREG TASK_PT_GR23(%r1),%r23
+ LDREG TASK_PT_GR24(%r1),%r24
+ LDREG TASK_PT_GR25(%r1),%r25
+ LDREG TASK_PT_GR26(%r1),%r26
+ LDREG TASK_PT_GR27(%r1),%r27 /* restore user dp */
+ LDREG TASK_PT_GR28(%r1),%r28 /* syscall return value */
+ LDREG TASK_PT_GR29(%r1),%r29
+ LDREG TASK_PT_GR31(%r1),%r31 /* restore syscall rp */
+
+ /* NOTE: We use rsm/ssm pair to make this operation atomic */
+ rsm PSW_SM_I, %r0
+ LDREG TASK_PT_GR30(%r1),%r30 /* restore user sp */
+ mfsp %sr3,%r1 /* Get users space id */
+ mtsp %r1,%sr7 /* Restore sr7 */
+ ssm PSW_SM_I, %r0
+
+ /* Set sr2 to zero for userspace syscalls to work. */
+ mtsp %r0,%sr2
+ mtsp %r1,%sr4 /* Restore sr4 */
+ mtsp %r1,%sr5 /* Restore sr5 */
+ mtsp %r1,%sr6 /* Restore sr6 */
+
+ depi 3,31,2,%r31 /* ensure return to user mode. */
+
+#ifdef __LP64__
+ /* decide whether to reset the wide mode bit
+ *
+ * For a syscall, the W bit is stored in the lowest bit
+ * of sp. Extract it and reset W if it is zero */
+ extrd,u,*<> %r30,63,1,%r1
+ rsm PSW_SM_W, %r0
+ /* now reset the lowest bit of sp if it was set */
+ xor %r30,%r1,%r30
+#endif
+ be,n 0(%sr3,%r31) /* return to user space */
+
+ /* We have to return via an RFI, so that PSW T and R bits can be set
+ * appropriately.
+ * This sets up pt_regs so we can return via intr_restore, which is not
+ * the most efficient way of doing things, but it works.
+ */
+syscall_restore_rfi:
+ ldo -1(%r0),%r2 /* Set recovery cntr to -1 */
+ mtctl %r2,%cr0 /* for immediate trap */
+ LDREG TASK_PT_PSW(%r1),%r2 /* Get old PSW */
+ ldi 0x0b,%r20 /* Create new PSW */
+ depi -1,13,1,%r20 /* C, Q, D, and I bits */
+
+ /* The values of PA_SINGLESTEP_BIT and PA_BLOCKSTEP_BIT are
+ * set in include/linux/ptrace.h and converted to PA bitmap
+ * numbers in asm-offsets.c */
+
+ /* if ((%r19.PA_SINGLESTEP_BIT)) { %r20.27=1} */
+ extru,= %r19,PA_SINGLESTEP_BIT,1,%r0
+ depi -1,27,1,%r20 /* R bit */
+
+ /* if ((%r19.PA_BLOCKSTEP_BIT)) { %r20.7=1} */
+ extru,= %r19,PA_BLOCKSTEP_BIT,1,%r0
+ depi -1,7,1,%r20 /* T bit */
+
+ STREG %r20,TASK_PT_PSW(%r1)
+
+ /* Always store space registers, since sr3 can be changed (e.g. fork) */
+
+ mfsp %sr3,%r25
+ STREG %r25,TASK_PT_SR3(%r1)
+ STREG %r25,TASK_PT_SR4(%r1)
+ STREG %r25,TASK_PT_SR5(%r1)
+ STREG %r25,TASK_PT_SR6(%r1)
+ STREG %r25,TASK_PT_SR7(%r1)
+ STREG %r25,TASK_PT_IASQ0(%r1)
+ STREG %r25,TASK_PT_IASQ1(%r1)
+
+ /* XXX W bit??? */
+ /* Now if old D bit is clear, it means we didn't save all registers
+ * on syscall entry, so do that now. This only happens on TRACEME
+ * calls, or if someone attached to us while we were on a syscall.
+ * We could make this more efficient by not saving r3-r18, but
+ * then we wouldn't be able to use the common intr_restore path.
+ * It is only for traced processes anyway, so performance is not
+ * an issue.
+ */
+ bb,< %r2,30,pt_regs_ok /* Branch if D set */
+ ldo TASK_REGS(%r1),%r25
+ reg_save %r25 /* Save r3 to r18 */
+
+ /* Save the current sr */
+ mfsp %sr0,%r2
+ STREG %r2,TASK_PT_SR0(%r1)
+
+ /* Save the scratch sr */
+ mfsp %sr1,%r2
+ STREG %r2,TASK_PT_SR1(%r1)
+
+ /* sr2 should be set to zero for userspace syscalls */
+ STREG %r0,TASK_PT_SR2(%r1)
+
+pt_regs_ok:
+ LDREG TASK_PT_GR31(%r1),%r2
+ depi 3,31,2,%r2 /* ensure return to user mode. */
+ STREG %r2,TASK_PT_IAOQ0(%r1)
+ ldo 4(%r2),%r2
+ STREG %r2,TASK_PT_IAOQ1(%r1)
+ copy %r25,%r16
+ b intr_restore
+ nop
+
+ .import do_softirq,code
+syscall_do_softirq:
+ bl do_softirq,%r2
+ nop
+ /* NOTE: We enable I-bit incase we schedule later,
+ * and we might be going back to userspace if we were
+ * traced. */
+ b syscall_check_resched
+ ssm PSW_SM_I, %r0 /* do_softirq returns with I bit off */
+
+ .import schedule,code
+syscall_do_resched:
+ BL schedule,%r2
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#else
+ nop
+#endif
+ b syscall_check_bh /* if resched, we start over again */
+ nop
+
+ .import do_signal,code
+syscall_do_signal:
+ /* Save callee-save registers (for sigcontext).
+ FIXME: After this point the process structure should be
+ consistent with all the relevant state of the process
+ before the syscall. We need to verify this. */
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1), %r25 /* struct pt_regs *regs */
+ reg_save %r25
+
+ ldi 1, %r24 /* unsigned long in_syscall */
+
+#ifdef __LP64__
+ ldo -16(%r30),%r29 /* Reference param save area */
+#endif
+ BL do_signal,%r2
+ copy %r0, %r26 /* sigset_t *oldset = NULL */
+
+ LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
+ ldo TASK_REGS(%r1), %r20 /* reload pt_regs */
+ reg_restore %r20
+
+ b,n syscall_check_sig
+
+ /*
+ * get_register is used by the non access tlb miss handlers to
+ * copy the value of the general register specified in r8 into
+ * r1. This routine can't be used for shadowed registers, since
+ * the rfir will restore the original value. So, for the shadowed
+ * registers we put a -1 into r1 to indicate that the register
+ * should not be used (the register being copied could also have
+ * a -1 in it, but that is OK, it just means that we will have
+ * to use the slow path instead).
+ */
+
+get_register:
+ blr %r8,%r0
+ nop
+ bv %r0(%r25) /* r0 */
+ copy %r0,%r1
+ bv %r0(%r25) /* r1 - shadowed */
+ ldi -1,%r1
+ bv %r0(%r25) /* r2 */
+ copy %r2,%r1
+ bv %r0(%r25) /* r3 */
+ copy %r3,%r1
+ bv %r0(%r25) /* r4 */
+ copy %r4,%r1
+ bv %r0(%r25) /* r5 */
+ copy %r5,%r1
+ bv %r0(%r25) /* r6 */
+ copy %r6,%r1
+ bv %r0(%r25) /* r7 */
+ copy %r7,%r1
+ bv %r0(%r25) /* r8 - shadowed */
+ ldi -1,%r1
+ bv %r0(%r25) /* r9 - shadowed */
+ ldi -1,%r1
+ bv %r0(%r25) /* r10 */
+ copy %r10,%r1
+ bv %r0(%r25) /* r11 */
+ copy %r11,%r1
+ bv %r0(%r25) /* r12 */
+ copy %r12,%r1
+ bv %r0(%r25) /* r13 */
+ copy %r13,%r1
+ bv %r0(%r25) /* r14 */
+ copy %r14,%r1
+ bv %r0(%r25) /* r15 */
+ copy %r15,%r1
+ bv %r0(%r25) /* r16 - shadowed */
+ ldi -1,%r1
+ bv %r0(%r25) /* r17 - shadowed */
+ ldi -1,%r1
+ bv %r0(%r25) /* r18 */
+ copy %r18,%r1
+ bv %r0(%r25) /* r19 */
+ copy %r19,%r1
+ bv %r0(%r25) /* r20 */
+ copy %r20,%r1
+ bv %r0(%r25) /* r21 */
+ copy %r21,%r1
+ bv %r0(%r25) /* r22 */
+ copy %r22,%r1
+ bv %r0(%r25) /* r23 */
+ copy %r23,%r1
+ bv %r0(%r25) /* r24 - shadowed */
+ ldi -1,%r1
+ bv %r0(%r25) /* r25 - shadowed */
+ ldi -1,%r1
+ bv %r0(%r25) /* r26 */
+ copy %r26,%r1
+ bv %r0(%r25) /* r27 */
+ copy %r27,%r1
+ bv %r0(%r25) /* r28 */
+ copy %r28,%r1
+ bv %r0(%r25) /* r29 */
+ copy %r29,%r1
+ bv %r0(%r25) /* r30 */
+ copy %r30,%r1
+ bv %r0(%r25) /* r31 */
+ copy %r31,%r1
+
+ /*
+ * set_register is used by the non access tlb miss handlers to
+ * copy the value of r1 into the general register specified in
+ * r8.
+ */
+
+set_register:
+ blr %r8,%r0
+ nop
+ bv %r0(%r25) /* r0 (silly, but it is a place holder) */
+ copy %r1,%r0
+ bv %r0(%r25) /* r1 */
+ copy %r1,%r1
+ bv %r0(%r25) /* r2 */
+ copy %r1,%r2
+ bv %r0(%r25) /* r3 */
+ copy %r1,%r3
+ bv %r0(%r25) /* r4 */
+ copy %r1,%r4
+ bv %r0(%r25) /* r5 */
+ copy %r1,%r5
+ bv %r0(%r25) /* r6 */
+ copy %r1,%r6
+ bv %r0(%r25) /* r7 */
+ copy %r1,%r7
+ bv %r0(%r25) /* r8 */
+ copy %r1,%r8
+ bv %r0(%r25) /* r9 */
+ copy %r1,%r9
+ bv %r0(%r25) /* r10 */
+ copy %r1,%r10
+ bv %r0(%r25) /* r11 */
+ copy %r1,%r11
+ bv %r0(%r25) /* r12 */
+ copy %r1,%r12
+ bv %r0(%r25) /* r13 */
+ copy %r1,%r13
+ bv %r0(%r25) /* r14 */
+ copy %r1,%r14
+ bv %r0(%r25) /* r15 */
+ copy %r1,%r15
+ bv %r0(%r25) /* r16 */
+ copy %r1,%r16
+ bv %r0(%r25) /* r17 */
+ copy %r1,%r17
+ bv %r0(%r25) /* r18 */
+ copy %r1,%r18
+ bv %r0(%r25) /* r19 */
+ copy %r1,%r19
+ bv %r0(%r25) /* r20 */
+ copy %r1,%r20
+ bv %r0(%r25) /* r21 */
+ copy %r1,%r21
+ bv %r0(%r25) /* r22 */
+ copy %r1,%r22
+ bv %r0(%r25) /* r23 */
+ copy %r1,%r23
+ bv %r0(%r25) /* r24 */
+ copy %r1,%r24
+ bv %r0(%r25) /* r25 */
+ copy %r1,%r25
+ bv %r0(%r25) /* r26 */
+ copy %r1,%r26
+ bv %r0(%r25) /* r27 */
+ copy %r1,%r27
+ bv %r0(%r25) /* r28 */
+ copy %r1,%r28
+ bv %r0(%r25) /* r29 */
+ copy %r1,%r29
+ bv %r0(%r25) /* r30 */
+ copy %r1,%r30
+ bv %r0(%r25) /* r31 */
+ copy %r1,%r31