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googlers / maze / linux / 66337dab951a9da0873bb1d7dbf36fb668417274 / . / arch / parisc / kernel / entry.S
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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 <asm/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/psw.h>
#include <asm/assembly.h> /* for LDREG/STREG defines */
#include <asm/pgtable.h>
#include <asm/signal.h>
#include <asm/unistd.h>
#include <asm/thread_info.h>
#ifdef CONFIG_64BIT
#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
/* pcxt_ssm_bug */
rsm PSW_SM_I, %r0 /* barrier for "Relied upon Translation */
mtsp %r0, %sr4
mtsp %r0, %sr5
mfsp %sr7, %r1
or,= %r0,%r1,%r0 /* Only save sr7 in sr3 if sr7 != 0 */
mtsp %r1, %sr3
tovirt_r1 %r29
load32 KERNEL_PSW, %r1
rsm PSW_SM_QUIET,%r0 /* second "heavy weight" ctl op */
mtsp %r0, %sr6
mtsp %r0, %sr7
mtctl %r0, %cr17 /* Clear IIASQ tail */
mtctl %r0, %cr17 /* Clear IIASQ head */
mtctl %r1, %ipsw
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 CONFIG_64BIT
/*
* 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 CONFIG_64BIT
b itlb_miss_20w
#else
b itlb_miss_20
#endif
mfctl %pcoq, va
.align 32
.endm
#ifndef CONFIG_64BIT
/*
* 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 CONFIG_64BIT
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 CONFIG_64BIT
/*
* 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 CONFIG_64BIT
b dtlb_miss_20w
#else
b dtlb_miss_20
#endif
mfctl %ior, va
.align 32
.endm
#ifndef CONFIG_64BIT
/* 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 CONFIG_64BIT
b nadtlb_miss_20w
#else
b nadtlb_miss_20
#endif
mfctl %ior,va
.align 32
.endm
#ifndef CONFIG_64BIT
/*
* 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 CONFIG_64BIT
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 CONFIG_64BIT
extrd,u \reg1,32+\start,\length,\reg2
#else
extrw,u \reg1,\start,\length,\reg2
#endif
.endm
.macro DEP reg1,start,length,reg2
#ifdef CONFIG_64BIT
depd \reg1,32+\start,\length,\reg2
#else
depw \reg1,\start,\length,\reg2
#endif
.endm
.macro DEPI val,start,length,reg
#ifdef CONFIG_64BIT
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 CONFIG_64BIT
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 CONFIG_64BIT
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
#if PT_NLEVELS == 3 /* we might have a 2-Level scheme, e.g. with 16kb page size */
extrd,u \va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
copy %r0,\pte
extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
ldw,s \index(\pgd),\pgd
extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
bb,>=,n \pgd,_PxD_PRESENT_BIT,\fault
extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
shld \pgd,PxD_VALUE_SHIFT,\index
extrd,u,*= \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
copy \index,\pgd
extrd,u,*<> \va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
ldo ASM_PGD_PMD_OFFSET(\pgd),\pgd
#endif
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 */
/* Enforce uncacheable pages.
* This should ONLY be use for MMIO on PA 2.0 machines.
* Memory/DMA is cache coherent on all PA2.0 machines we support
* (that means T-class is NOT supported) and the memory controllers
* on most of those machines only handles cache transactions.
*/
extrd,u,*= \pte,_PAGE_NO_CACHE_BIT+32,1,%r0
depi 1,12,1,\prot
/* Drop prot bits and convert to page addr for iitlbt and idtlbt */
extrd,u \pte,(63-ASM_PFN_PTE_SHIFT)+(63-58),64-PAGE_SHIFT,\pte
depdi _PAGE_SIZE_ENCODING_DEFAULT,63,63-58,\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 _PAGE_SIZE_ENCODING_DEFAULT,31,ASM_PFN_PTE_SHIFT,\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(CONFIG_64BIT) && (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 CONFIG_64BIT
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 CONFIG_64BIT
.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 CONFIG_64BIT
/* 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 CONFIG_64BIT
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 CONFIG_64BIT
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 CONFIG_64BIT
ldo -16(%r30),%r29 /* Reference param save area */
loadgp /* Thread could have been in a module */
#endif
#ifndef CONFIG_64BIT
b sys_exit
#else
load32 sys_exit, %r1
bv %r0(%r1)
#endif
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 CONFIG_64BIT
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_float
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
callee_rest_float
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].
*
*/
.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 CONFIG_64BIT
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 CONFIG_64BIT
shld %r1, 6, %r20
#else
shlw %r1, 5, %r20
#endif
add %r19,%r20,%r19 /* now have &irq_stat[smp_processor_id()] */
#endif /* CONFIG_SMP */
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
/* inverse of virt_map */
pcxt_ssm_bug
rsm PSW_SM_QUIET,%r0 /* prepare for rfi */
tophys_r1 %r29
/* Restore space id's and special cr's from PT_REGS
* structure pointed to by r29
*/
rest_specials %r29
/* IMPORTANT: 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
#ifndef CONFIG_PREEMPT
# define intr_do_preempt intr_restore
#endif /* !CONFIG_PREEMPT */
.import schedule,code
intr_do_resched:
/* Only call schedule on return to userspace. If we're returning
* to kernel space, we may schedule if CONFIG_PREEMPT, otherwise
* we jump back to intr_restore.
*/
LDREG PT_IASQ0(%r16), %r20
CMPIB= 0, %r20, intr_do_preempt
nop
LDREG PT_IASQ1(%r16), %r20
CMPIB= 0, %r20, intr_do_preempt
nop
#ifdef CONFIG_64BIT
ldo -16(%r30),%r29 /* Reference param save area */
#endif
ldil L%intr_check_sig, %r2
#ifndef CONFIG_64BIT
b schedule
#else
load32 schedule, %r20
bv %r0(%r20)
#endif
ldo R%intr_check_sig(%r2), %r2
/* preempt the current task on returning to kernel
* mode from an interrupt, iff need_resched is set,
* and preempt_count is 0. otherwise, we continue on
* our merry way back to the current running task.
*/
#ifdef CONFIG_PREEMPT
.import preempt_schedule_irq,code
intr_do_preempt:
rsm PSW_SM_I, %r0 /* disable interrupts */
/* current_thread_info()->preempt_count */
mfctl %cr30, %r1
LDREG TI_PRE_COUNT(%r1), %r19
CMPIB<> 0, %r19, intr_restore /* if preempt_count > 0 */
nop /* prev insn branched backwards */
/* check if we interrupted a critical path */
LDREG PT_PSW(%r16), %r20
bb,<,n %r20, 31 - PSW_SM_I, intr_restore
nop
BL preempt_schedule_irq, %r2
nop
b intr_restore /* ssm PSW_SM_I done by intr_restore */
#endif /* CONFIG_PREEMPT */
.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 CONFIG_64BIT
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 CONFIG_64BIT
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 CONFIG_64BIT
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
mfctl %cr20, %r16 /* isr */
nop /* serialize mfctl on PA 2.0 to avoid 4 cycle penalty */
mfctl %cr21, %r17 /* ior */
#ifdef CONFIG_64BIT
/*
* If the interrupted code was running with W bit off (32 bit),
* clear the b bits (bits 0 & 1) in the ior.
* save_specials left ipsw value in r8 for us to test.
*/
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,SPACEID_SHIFT,%r1 /* get high bits from isr for ior */
depd %r1,31,SPACEID_SHIFT,%r17 /* deposit them into ior */
depdi 0,63,SPACEID_SHIFT,%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 CONFIG_64BIT
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 CONFIG_64BIT
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 %ipsw,%r8
ldil L%PSW_N,%r9
or %r8,%r9,%r8 /* Set PSW_N */
mtctl %r8,%ipsw
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 CONFIG_64BIT
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 CONFIG_64BIT
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 CONFIG_64BIT
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 CONFIG_64BIT
ldo -16(%r30),%r29 /* Reference param save area */
#endif
/* WARNING - Clobbers r19 and r21, userspace must save these! */
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 CONFIG_64BIT
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 CONFIG_64BIT
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 CONFIG_64BIT
.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 CONFIG_64BIT
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 CONFIG_64BIT
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 CONFIG_64BIT
.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 CONFIG_64BIT
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 CONFIG_64BIT
shld %r26, 6, %r20
#else
shlw %r26, 5, %r20
#endif
add %r19,%r20,%r19 /* now have &irq_stat[smp_processor_id()] */
#endif /* CONFIG_SMP */
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 CONFIG_64BIT
/* 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 schedule,code
syscall_do_resched:
BL schedule,%r2
#ifdef CONFIG_64BIT
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 CONFIG_64BIT
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