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linux / linux / kernel / git / torvalds / linux / 96f86ff08332d88defd35c330fc6dae219b9e264 / . / arch / parisc / kernel / entry.S
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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* 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)
*/
#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/cache.h> /* for L1_CACHE_SHIFT */
#include <asm/assembly.h> /* for LDREG/STREG defines */
#include <asm/signal.h>
#include <asm/unistd.h>
#include <asm/ldcw.h>
#include <asm/traps.h>
#include <asm/thread_info.h>
#include <asm/alternative.h>
#include <linux/linkage.h>
#include <linux/pgtable.h>
#ifdef CONFIG_64BIT
.level 2.0w
#else
.level 2.0
#endif
/* Get aligned page_table_lock address for this mm from cr28/tr4 */
.macro get_ptl reg
mfctl %cr28,\reg
.endm
/* 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
/*
* The "get_stack" macros are responsible for determining the
* kernel stack value.
*
* 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. Load the stack
* pointer from the task structure.
*
* 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.
*/
.macro get_stack_use_cr30
/* we save the registers in the task struct */
copy %r30, %r17
mfctl %cr30, %r1
tophys %r1,%r9 /* task_struct */
LDREG TASK_STACK(%r9),%r30
ldo PT_SZ_ALGN(%r30),%r30
mtsp %r0,%sr7 /* clear sr7 after kernel stack was set! */
mtsp %r16,%sr3
ldo TASK_REGS(%r9),%r9
STREG %r17,PT_GR30(%r9)
STREG %r29,PT_GR29(%r9)
STREG %r26,PT_GR26(%r9)
STREG %r16,PT_SR7(%r9)
copy %r9,%r29
.endm
.macro get_stack_use_r30
/* we put a struct pt_regs on the stack and save the registers there */
tophys %r30,%r9
copy %r30,%r1
ldo PT_SZ_ALGN(%r30),%r30
STREG %r1,PT_GR30(%r9)
STREG %r29,PT_GR29(%r9)
STREG %r26,PT_GR26(%r9)
STREG %r16,PT_SR7(%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 0 /* 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 occurred */
spc = r24 /* space for which the trap occurred */
#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)
*/
.macro naitlb_11 code
mfctl %isr,spc
b naitlb_miss_11
mfctl %ior,va
.align 32
.endm
#endif
/*
* naitlb miss interruption handler (parisc 2.0)
*/
.macro naitlb_20 code
mfctl %isr,spc
#ifdef CONFIG_64BIT
b naitlb_miss_20w
#else
b naitlb_miss_20
#endif
mfctl %ior,va
.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
/* 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
/* check against %r0 which is same value as LINUX_GATEWAY_SPACE */
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 CONFIG_PGTABLE_LEVELS == 3
extru_safe \va,31-ASM_PMD_SHIFT,ASM_BITS_PER_PMD,\index
#else
extru_safe \va,31-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
#endif
dep %r0,31,PAGE_SHIFT,\pmd /* clear offset */
#if CONFIG_PGTABLE_LEVELS < 3
copy %r0,\pte
#endif
ldw,s \index(\pmd),\pmd
bb,>=,n \pmd,_PxD_PRESENT_BIT,\fault
dep %r0,31,PxD_FLAG_SHIFT,\pmd /* clear flags */
SHLREG \pmd,PxD_VALUE_SHIFT,\pmd
extru_safe \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 /* pmd is now pte */
.endm
/* Look up PTE in a 3-Level scheme. */
.macro L3_ptep pgd,pte,index,va,fault
#if CONFIG_PGTABLE_LEVELS == 3
copy %r0,\pte
extrd,u \va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
ldw,s \index(\pgd),\pgd
bb,>=,n \pgd,_PxD_PRESENT_BIT,\fault
shld \pgd,PxD_VALUE_SHIFT,\pgd
#endif
L2_ptep \pgd,\pte,\index,\va,\fault
.endm
/* Acquire page_table_lock and check page is present. */
.macro ptl_lock spc,ptp,pte,tmp,tmp1,fault
#ifdef CONFIG_TLB_PTLOCK
98: cmpib,COND(=),n 0,\spc,2f
get_ptl \tmp
1: LDCW 0(\tmp),\tmp1
cmpib,COND(=) 0,\tmp1,1b
nop
LDREG 0(\ptp),\pte
bb,<,n \pte,_PAGE_PRESENT_BIT,3f
b \fault
stw \spc,0(\tmp)
99: ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
#endif
2: LDREG 0(\ptp),\pte
bb,>=,n \pte,_PAGE_PRESENT_BIT,\fault
3:
.endm
/* Release page_table_lock without reloading lock address.
Note that the values in the register spc are limited to
NR_SPACE_IDS (262144). Thus, the stw instruction always
stores a nonzero value even when register spc is 64 bits.
We use an ordered store to ensure all prior accesses are
performed prior to releasing the lock. */
.macro ptl_unlock0 spc,tmp
#ifdef CONFIG_TLB_PTLOCK
98: or,COND(=) %r0,\spc,%r0
stw,ma \spc,0(\tmp)
99: ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
#endif
.endm
/* Release page_table_lock. */
.macro ptl_unlock1 spc,tmp
#ifdef CONFIG_TLB_PTLOCK
98: get_ptl \tmp
ptl_unlock0 \spc,\tmp
99: ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
#endif
.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_accessed ptp,pte,tmp,tmp1
ldi _PAGE_ACCESSED,\tmp1
or \tmp1,\pte,\tmp
and,COND(<>) \tmp1,\pte,%r0
STREG \tmp,0(\ptp)
.endm
/* Set the dirty bit (and accessed bit). No need to be
* clever, this is only used from the dirty fault */
.macro update_dirty ptp,pte,tmp
ldi _PAGE_ACCESSED|_PAGE_DIRTY,\tmp
or \tmp,\pte,\pte
STREG \pte,0(\ptp)
.endm
/* We have (depending on the page size):
* - 38 to 52-bit Physical Page Number
* - 12 to 26-bit page offset
*/
/* bitshift difference between a PFN (based on kernel's PAGE_SIZE)
* to a CPU TLB 4k PFN (4k => 12 bits to shift) */
#define PAGE_ADD_SHIFT (PAGE_SHIFT-12)
#define PAGE_ADD_HUGE_SHIFT (REAL_HPAGE_SHIFT-12)
/* Drop prot bits and convert to page addr for iitlbt and idtlbt */
.macro convert_for_tlb_insert20 pte,tmp
#ifdef CONFIG_HUGETLB_PAGE
copy \pte,\tmp
extrd,u \tmp,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
depdi _PAGE_SIZE_ENCODING_DEFAULT,63,\
(63-58)+PAGE_ADD_SHIFT,\pte
extrd,u,*= \tmp,_PAGE_HPAGE_BIT+32,1,%r0
depdi _HUGE_PAGE_SIZE_ENCODING_DEFAULT,63,\
(63-58)+PAGE_ADD_HUGE_SHIFT,\pte
#else /* Huge pages disabled */
extrd,u \pte,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
depdi _PAGE_SIZE_ENCODING_DEFAULT,63,\
(63-58)+PAGE_ADD_SHIFT,\pte
#endif
.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,tmp
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 and _PAGE_WRITE
* 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
depdi 1,12,1,\prot
/* Drop prot bits and convert to page addr for iitlbt and idtlbt */
convert_for_tlb_insert20 \pte \tmp
.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,ASM_PFN_PTE_SHIFT,\pte
SHRREG \pte,(ASM_PFN_PTE_SHIFT-(31-26)),\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 comprised of a pair of 4 MB regions
* aligned to 8 MB. It is used to clear/copy/flush user pages
* using kernel virtual 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,patype
cmpib,COND(<>),n 0,\spc,\fault
ldil L%(TMPALIAS_MAP_START),\tmp
copy \va,\tmp1
depi_safe 0,31,TMPALIAS_SIZE_BITS+1,\tmp1
cmpb,COND(<>),n \tmp,\tmp1,\fault
mfctl %cr19,\tmp /* iir */
/* get the opcode (first six bits) into \tmp */
extrw,u \tmp,5,6,\tmp
/*
* Only setting the T bit prevents data cache movein
* Setting access rights to zero prevents instruction cache movein
*
* Note subtlety here: _PAGE_GATEWAY, _PAGE_EXEC and _PAGE_WRITE go
* to type field and _PAGE_READ goes to top bit of PL1
*/
ldi (_PAGE_REFTRAP|_PAGE_READ|_PAGE_WRITE),\prot
/*
* so if the opcode is one (i.e. this is a memory management
* instruction) nullify the next load so \prot is only T.
* Otherwise this is a normal data operation
*/
cmpiclr,= 0x01,\tmp,%r0
ldi (_PAGE_DIRTY|_PAGE_READ|_PAGE_WRITE),\prot
.ifc \patype,20
depd,z \prot,8,7,\prot
.else
.ifc \patype,11
depw,z \prot,8,7,\prot
.else
.error "undefined PA type to do_alias"
.endif
.endif
/*
* 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,31-TMPALIAS_SIZE_BITS,1,%r0
or,COND(tr) %r23,%r0,\pte
or %r26,%r0,\pte
/* convert phys addr in \pte (from r23 or r26) to tlb insert format */
SHRREG \pte,PAGE_SHIFT+PAGE_ADD_SHIFT-5, \pte
depi_safe _PAGE_SIZE_ENCODING_DEFAULT, 31,5, \pte
.endm
/*
* Fault_vectors are architecturally required to be aligned on a 2K
* boundary
*/
.section .text.hot
.align 2048
ENTRY(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 PARISC_ITLB_TRAP
def 7
def 8
def 9
def 10
def 11
def 12
def 13
def 14
dtlb_20 15
naitlb_20 16
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
END(fault_vector_20)
#ifndef CONFIG_64BIT
.align 2048
ENTRY(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 PARISC_ITLB_TRAP
def 7
def 8
def 9
def 10
def 11
def 12
def 13
def 14
dtlb_11 15
naitlb_11 16
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
END(fault_vector_11)
#endif
/* Fault vector is separately protected and *must* be on its own page */
.align PAGE_SIZE
.import handle_interruption,code
.import do_cpu_irq_mask,code
/*
* Child Returns here
*
* copy_thread moved args into task save area.
*/
ENTRY(ret_from_kernel_thread)
/* Call schedule_tail first though */
BL schedule_tail, %r2
nop
mfctl %cr30,%r1 /* task_struct */
LDREG TASK_PT_GR25(%r1), %r26
#ifdef CONFIG_64BIT
LDREG TASK_PT_GR27(%r1), %r27
#endif
LDREG TASK_PT_GR26(%r1), %r1
ble 0(%sr7, %r1)
copy %r31, %r2
b finish_child_return
nop
END(ret_from_kernel_thread)
/*
* struct task_struct *_switch_to(struct task_struct *prev,
* struct task_struct *next)
*
* switch kernel stacks and return prev */
ENTRY_CFI(_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
bv %r0(%r2)
mtctl %r25,%cr30
ENTRY(_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
ENDPROC_CFI(_switch_to)
/*
* 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 PAGE_SIZE
ENTRY_CFI(syscall_exit_rfi)
mfctl %cr30,%r16 /* 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 PRIV_USER,31,2,%r19
STREG %r19,PT_IAOQ0(%r16)
LDREG PT_IAOQ1(%r16),%r19
depi PRIV_USER,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 occurred while on the gateway
* page). Note that we may be "trashing" values the user put in
* them, but we don't support 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)
ENTRY(intr_return)
/* check for reschedule */
mfctl %cr30,%r1
LDREG TASK_TI_FLAGS(%r1),%r19 /* sched.h: TIF_NEED_RESCHED */
bb,<,n %r19,31-TIF_NEED_RESCHED,intr_do_resched /* forward */
.import do_notify_resume,code
intr_check_sig:
/* As above */
mfctl %cr30,%r1
LDREG TASK_TI_FLAGS(%r1),%r19
ldi (_TIF_USER_WORK_MASK & ~_TIF_NEED_RESCHED), %r20
and,COND(<>) %r19, %r20, %r0
b,n intr_restore /* skip past if we've nothing to do */
/* 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,COND(=),n LINUX_GATEWAY_SPACE, %r20, intr_restore /* forward */
LDREG PT_IASQ1(%r16), %r20
cmpib,COND(=),n LINUX_GATEWAY_SPACE, %r20, intr_restore /* forward */
copy %r0, %r25 /* long in_syscall = 0 */
#ifdef CONFIG_64BIT
ldo -16(%r30),%r29 /* Reference param save area */
#endif
/* NOTE: We need to enable interrupts if we have to deliver
* signals. We used to do this earlier but it caused kernel
* stack overflows. */
ssm PSW_SM_I, %r0
BL do_notify_resume,%r2
copy %r16, %r26 /* struct pt_regs *regs */
b,n intr_check_sig
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
#ifndef CONFIG_PREEMPTION
# define intr_do_preempt intr_restore
#endif /* !CONFIG_PREEMPTION */
.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_PREEMPTION, otherwise
* we jump back to intr_restore.
*/
LDREG PT_IASQ0(%r16), %r20
cmpib,COND(=) 0, %r20, intr_do_preempt
nop
LDREG PT_IASQ1(%r16), %r20
cmpib,COND(=) 0, %r20, intr_do_preempt
nop
/* NOTE: We need to enable interrupts if we schedule. We used
* to do this earlier but it caused kernel stack overflows. */
ssm PSW_SM_I, %r0
#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_PREEMPTION
.import preempt_schedule_irq,code
intr_do_preempt:
rsm PSW_SM_I, %r0 /* disable interrupts */
/* current_thread_info()->preempt_count */
mfctl %cr30, %r1
ldw 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
/* ssm PSW_SM_I done later in intr_restore */
#ifdef CONFIG_MLONGCALLS
ldil L%intr_restore, %r2
load32 preempt_schedule_irq, %r1
bv %r0(%r1)
ldo R%intr_restore(%r2), %r2
#else
ldil L%intr_restore, %r1
BL preempt_schedule_irq, %r2
ldo R%intr_restore(%r1), %r2
#endif
#endif /* CONFIG_PREEMPTION */
/*
* External interrupts.
*/
intr_extint:
cmpib,COND(=),n 0,%r16,1f
get_stack_use_cr30
b,n 2f
1:
get_stack_use_r30
2:
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 */
ENDPROC_CFI(syscall_exit_rfi)
/* Generic interruptions (illegal insn, unaligned, page fault, etc) */
ENTRY_CFI(intr_save) /* for os_hpmc */
mfsp %sr7,%r16
cmpib,COND(=),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 */
cmpib,COND(=),n PARISC_ITLB_TRAP,%r26,skip_save_ior
mfctl %isr, %r16
nop /* serialize mfctl on PA 2.0 to avoid 4 cycle penalty */
mfctl %ior, %r17
#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
/* adjust isr/ior: get high bits from isr and deposit in ior */
space_adjust %r16,%r17,%r1
#endif
STREG %r16, PT_ISR(%r29)
STREG %r17, PT_IOR(%r29)
#if 0 && defined(CONFIG_64BIT)
/* Revisit when we have 64-bit code above 4Gb */
b,n intr_save2
skip_save_ior:
/* We have a itlb miss, and when executing code above 4 Gb on ILP64, we
* need to adjust iasq/iaoq here in the same way we adjusted isr/ior
* above.
*/
extrd,u,* %r8,PSW_W_BIT,1,%r1
cmpib,COND(=),n 1,%r1,intr_save2
LDREG PT_IASQ0(%r29), %r16
LDREG PT_IAOQ0(%r29), %r17
/* adjust iasq/iaoq */
space_adjust %r16,%r17,%r1
STREG %r16, PT_IASQ0(%r29)
STREG %r17, PT_IAOQ0(%r29)
#else
skip_save_ior:
#endif
intr_save2:
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
ENDPROC_CFI(intr_save)
/*
* 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 occurred */
t1 = r9 /* temporary register 1 */
pte = r16 /* pte/phys page # */
prot = r17 /* prot bits */
spc = r24 /* space for which the trap occurred */
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
ptl_lock spc,ptp,pte,t0,t1,dtlb_check_alias_20w
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
idtlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
dtlb_check_alias_20w:
do_alias spc,t0,t1,va,pte,prot,dtlb_fault,20
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_alias_20w
ptl_lock spc,ptp,pte,t0,t1,nadtlb_check_alias_20w
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
idtlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
nadtlb_check_alias_20w:
do_alias spc,t0,t1,va,pte,prot,nadtlb_emulate,20
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
ptl_lock spc,ptp,pte,t0,t1,dtlb_check_alias_11
update_accessed ptp,pte,t0,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 */
ptl_unlock1 spc,t0
rfir
nop
dtlb_check_alias_11:
do_alias spc,t0,t1,va,pte,prot,dtlb_fault,11
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_alias_11
ptl_lock spc,ptp,pte,t0,t1,nadtlb_check_alias_11
update_accessed ptp,pte,t0,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 */
ptl_unlock1 spc,t0
rfir
nop
nadtlb_check_alias_11:
do_alias spc,t0,t1,va,pte,prot,nadtlb_emulate,11
idtlba pte,(va)
idtlbp prot,(va)
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
ptl_lock spc,ptp,pte,t0,t1,dtlb_check_alias_20
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
f_extend pte,t1
idtlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
dtlb_check_alias_20:
do_alias spc,t0,t1,va,pte,prot,dtlb_fault,20
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_alias_20
ptl_lock spc,ptp,pte,t0,t1,nadtlb_check_alias_20
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
f_extend pte,t1
idtlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
nadtlb_check_alias_20:
do_alias spc,t0,t1,va,pte,prot,nadtlb_emulate,20
idtlbt pte,prot
rfir
nop
#endif
nadtlb_emulate:
/*
* Non-access misses can be caused by fdc,fic,pdc,lpa,probe and
* probei instructions. The kernel no longer faults doing flushes.
* Use of lpa and probe instructions is rare. Given the issue
* with shadow registers, we defer everything to the "slow" path.
*/
b,n nadtlb_fault
#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
ptl_lock spc,ptp,pte,t0,t1,itlb_fault
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
iitlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
naitlb_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,naitlb_fault
L3_ptep ptp,pte,t0,va,naitlb_check_alias_20w
ptl_lock spc,ptp,pte,t0,t1,naitlb_check_alias_20w
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
iitlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
naitlb_check_alias_20w:
do_alias spc,t0,t1,va,pte,prot,naitlb_fault,20
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
ptl_lock spc,ptp,pte,t0,t1,itlb_fault
update_accessed ptp,pte,t0,t1
make_insert_tlb_11 spc,pte,prot
mfsp %sr1,t1 /* Save sr1 so we can use it in tlb inserts */
mtsp spc,%sr1
iitlba pte,(%sr1,va)
iitlbp prot,(%sr1,va)
mtsp t1, %sr1 /* Restore sr1 */
ptl_unlock1 spc,t0
rfir
nop
naitlb_miss_11:
get_pgd spc,ptp
space_check spc,t0,naitlb_fault
L2_ptep ptp,pte,t0,va,naitlb_check_alias_11
ptl_lock spc,ptp,pte,t0,t1,naitlb_check_alias_11
update_accessed ptp,pte,t0,t1
make_insert_tlb_11 spc,pte,prot
mfsp %sr1,t1 /* Save sr1 so we can use it in tlb inserts */
mtsp spc,%sr1
iitlba pte,(%sr1,va)
iitlbp prot,(%sr1,va)
mtsp t1, %sr1 /* Restore sr1 */
ptl_unlock1 spc,t0
rfir
nop
naitlb_check_alias_11:
do_alias spc,t0,t1,va,pte,prot,itlb_fault,11
iitlba pte,(%sr0, va)
iitlbp prot,(%sr0, va)
rfir
nop
itlb_miss_20:
get_pgd spc,ptp
space_check spc,t0,itlb_fault
L2_ptep ptp,pte,t0,va,itlb_fault
ptl_lock spc,ptp,pte,t0,t1,itlb_fault
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
f_extend pte,t1
iitlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
naitlb_miss_20:
get_pgd spc,ptp
space_check spc,t0,naitlb_fault
L2_ptep ptp,pte,t0,va,naitlb_check_alias_20
ptl_lock spc,ptp,pte,t0,t1,naitlb_check_alias_20
update_accessed ptp,pte,t0,t1
make_insert_tlb spc,pte,prot,t1
f_extend pte,t1
iitlbt pte,prot
ptl_unlock1 spc,t0
rfir
nop
naitlb_check_alias_20:
do_alias spc,t0,t1,va,pte,prot,naitlb_fault,20
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
ptl_lock spc,ptp,pte,t0,t1,dbit_fault
update_dirty ptp,pte,t1
make_insert_tlb spc,pte,prot,t1
idtlbt pte,prot
ptl_unlock0 spc,t0
rfir
nop
#else
dbit_trap_11:
get_pgd spc,ptp
space_check spc,t0,dbit_fault
L2_ptep ptp,pte,t0,va,dbit_fault
ptl_lock spc,ptp,pte,t0,t1,dbit_fault
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 */
ptl_unlock0 spc,t0
rfir
nop
dbit_trap_20:
get_pgd spc,ptp
space_check spc,t0,dbit_fault
L2_ptep ptp,pte,t0,va,dbit_fault
ptl_lock spc,ptp,pte,t0,t1,dbit_fault
update_dirty ptp,pte,t1
make_insert_tlb spc,pte,prot,t1
f_extend pte,t1
idtlbt pte,prot
ptl_unlock0 spc,t0
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 PARISC_ITLB_TRAP,%r8
nadtlb_fault:
b intr_save
ldi 17,%r8
naitlb_fault:
b intr_save
ldi 16,%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
.macro fork_like name
ENTRY_CFI(sys_\name\()_wrapper)
mfctl %cr30,%r1
ldo TASK_REGS(%r1),%r1
reg_save %r1
mfctl %cr27, %r28
ldil L%sys_\name, %r31
be R%sys_\name(%sr4,%r31)
STREG %r28, PT_CR27(%r1)
ENDPROC_CFI(sys_\name\()_wrapper)
.endm
fork_like clone
fork_like clone3
fork_like fork
fork_like vfork
/* Set the return value for the child */
ENTRY(child_return)
BL schedule_tail, %r2
nop
finish_child_return:
mfctl %cr30,%r1
ldo TASK_REGS(%r1),%r1 /* get pt regs */
LDREG PT_CR27(%r1), %r3
mtctl %r3, %cr27
reg_restore %r1
b syscall_exit
copy %r0,%r28
END(child_return)
ENTRY_CFI(sys_rt_sigreturn_wrapper)
mfctl %cr30,%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. */
mfctl %cr30,%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 */
ENDPROC_CFI(sys_rt_sigreturn_wrapper)
ENTRY(syscall_exit)
/* 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
STREG %r28,TASK_PT_GR28(%r1)
/* 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_resched:
/* check for reschedule */
mfctl %cr30,%r19
LDREG TASK_TI_FLAGS(%r19),%r19 /* long */
bb,<,n %r19, 31-TIF_NEED_RESCHED, syscall_do_resched /* forward */
.import do_signal,code
syscall_check_sig:
mfctl %cr30,%r19
LDREG TASK_TI_FLAGS(%r19),%r19
ldi (_TIF_USER_WORK_MASK & ~_TIF_NEED_RESCHED), %r26
and,COND(<>) %r19, %r26, %r0
b,n syscall_restore /* skip past if we've nothing to do */
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.
*/
mfctl %cr30,%r1
ldo TASK_REGS(%r1), %r26 /* struct pt_regs *regs */
reg_save %r26
#ifdef CONFIG_64BIT
ldo -16(%r30),%r29 /* Reference param save area */
#endif
BL do_notify_resume,%r2
ldi 1, %r25 /* long in_syscall = 1 */
mfctl %cr30,%r1
ldo TASK_REGS(%r1), %r20 /* reload pt_regs */
reg_restore %r20
b,n syscall_check_sig
syscall_restore:
mfctl %cr30,%r1
/* Are we being ptraced? */
LDREG TASK_TI_FLAGS(%r1),%r19
ldi _TIF_SINGLESTEP|_TIF_BLOCKSTEP,%r2
and,COND(=) %r19,%r2,%r0
b,n syscall_restore_rfi
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 */
LDREG TASK_PT_GR30(%r1),%r1 /* Get user sp */
rsm PSW_SM_I, %r0
copy %r1,%r30 /* Restore user sp */
mfsp %sr3,%r1 /* Get user 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 PRIV_USER,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 SINGLESTEP_BIT and BLOCKSTEP_BIT are
* set in thread_info.h and converted to PA bitmap
* numbers in asm-offsets.c */
/* if ((%r19.SINGLESTEP_BIT)) { %r20.27=1} */
extru,= %r19,TIF_SINGLESTEP_PA_BIT,1,%r0
depi -1,27,1,%r20 /* R bit */
/* if ((%r19.BLOCKSTEP_BIT)) { %r20.7=1} */
extru,= %r19,TIF_BLOCKSTEP_PA_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)
LDREG TASK_PT_GR31(%r1),%r2
depi PRIV_USER,31,2,%r2 /* ensure return to user mode. */
STREG %r2,TASK_PT_IAOQ0(%r1)
ldo 4(%r2),%r2
STREG %r2,TASK_PT_IAOQ1(%r1)
b intr_restore
copy %r25,%r16
pt_regs_ok:
LDREG TASK_PT_IAOQ0(%r1),%r2
depi PRIV_USER,31,2,%r2 /* ensure return to user mode. */
STREG %r2,TASK_PT_IAOQ0(%r1)
LDREG TASK_PT_IAOQ1(%r1),%r2
depi PRIV_USER,31,2,%r2
STREG %r2,TASK_PT_IAOQ1(%r1)
b intr_restore
copy %r25,%r16
syscall_do_resched:
load32 syscall_check_resched,%r2 /* if resched, we start over again */
load32 schedule,%r19
bv %r0(%r19) /* jumps to schedule() */
#ifdef CONFIG_64BIT
ldo -16(%r30),%r29 /* Reference param save area */
#else
nop
#endif
END(syscall_exit)
#ifdef CONFIG_FUNCTION_TRACER
.import ftrace_function_trampoline,code
.align L1_CACHE_BYTES
ENTRY_CFI(mcount, caller)
_mcount:
.export _mcount,data
/*
* The 64bit mcount() function pointer needs 4 dwords, of which the
* first two are free. We optimize it here and put 2 instructions for
* calling mcount(), and 2 instructions for ftrace_stub(). That way we
* have all on one L1 cacheline.
*/
ldi 0, %arg3
b ftrace_function_trampoline
copy %r3, %arg2 /* caller original %sp */
ftrace_stub:
.globl ftrace_stub
.type ftrace_stub, @function
#ifdef CONFIG_64BIT
bve (%rp)
#else
bv %r0(%rp)
#endif
nop
#ifdef CONFIG_64BIT
.dword mcount
.dword 0 /* code in head.S puts value of global gp here */
#endif
ENDPROC_CFI(mcount)
#ifdef CONFIG_DYNAMIC_FTRACE
#ifdef CONFIG_64BIT
#define FTRACE_FRAME_SIZE (2*FRAME_SIZE)
#else
#define FTRACE_FRAME_SIZE FRAME_SIZE
#endif
ENTRY_CFI(ftrace_caller, caller,frame=FTRACE_FRAME_SIZE,CALLS,SAVE_RP,SAVE_SP)
ftrace_caller:
.global ftrace_caller
STREG %r3, -FTRACE_FRAME_SIZE+1*REG_SZ(%sp)
ldo -FTRACE_FRAME_SIZE(%sp), %r3
STREG %rp, -RP_OFFSET(%r3)
/* Offset 0 is already allocated for %r1 */
STREG %r23, 2*REG_SZ(%r3)
STREG %r24, 3*REG_SZ(%r3)
STREG %r25, 4*REG_SZ(%r3)
STREG %r26, 5*REG_SZ(%r3)
STREG %r28, 6*REG_SZ(%r3)
STREG %r29, 7*REG_SZ(%r3)
#ifdef CONFIG_64BIT
STREG %r19, 8*REG_SZ(%r3)
STREG %r20, 9*REG_SZ(%r3)
STREG %r21, 10*REG_SZ(%r3)
STREG %r22, 11*REG_SZ(%r3)
STREG %r27, 12*REG_SZ(%r3)
STREG %r31, 13*REG_SZ(%r3)
loadgp
ldo -16(%sp),%r29
#endif
LDREG 0(%r3), %r25
copy %rp, %r26
ldo -8(%r25), %r25
ldi 0, %r23 /* no pt_regs */
b,l ftrace_function_trampoline, %rp
copy %r3, %r24
LDREG -RP_OFFSET(%r3), %rp
LDREG 2*REG_SZ(%r3), %r23
LDREG 3*REG_SZ(%r3), %r24
LDREG 4*REG_SZ(%r3), %r25
LDREG 5*REG_SZ(%r3), %r26
LDREG 6*REG_SZ(%r3), %r28
LDREG 7*REG_SZ(%r3), %r29
#ifdef CONFIG_64BIT
LDREG 8*REG_SZ(%r3), %r19
LDREG 9*REG_SZ(%r3), %r20
LDREG 10*REG_SZ(%r3), %r21
LDREG 11*REG_SZ(%r3), %r22
LDREG 12*REG_SZ(%r3), %r27
LDREG 13*REG_SZ(%r3), %r31
#endif
LDREG 1*REG_SZ(%r3), %r3
LDREGM -FTRACE_FRAME_SIZE(%sp), %r1
/* Adjust return point to jump back to beginning of traced function */
ldo -4(%r1), %r1
bv,n (%r1)
ENDPROC_CFI(ftrace_caller)
#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS
ENTRY_CFI(ftrace_regs_caller,caller,frame=FTRACE_FRAME_SIZE+PT_SZ_ALGN,
CALLS,SAVE_RP,SAVE_SP)
ftrace_regs_caller:
.global ftrace_regs_caller
ldo -FTRACE_FRAME_SIZE(%sp), %r1
STREG %rp, -RP_OFFSET(%r1)
copy %sp, %r1
ldo PT_SZ_ALGN(%sp), %sp
STREG %rp, PT_GR2(%r1)
STREG %r3, PT_GR3(%r1)
STREG %r4, PT_GR4(%r1)
STREG %r5, PT_GR5(%r1)
STREG %r6, PT_GR6(%r1)
STREG %r7, PT_GR7(%r1)
STREG %r8, PT_GR8(%r1)
STREG %r9, PT_GR9(%r1)
STREG %r10, PT_GR10(%r1)
STREG %r11, PT_GR11(%r1)
STREG %r12, PT_GR12(%r1)
STREG %r13, PT_GR13(%r1)
STREG %r14, PT_GR14(%r1)
STREG %r15, PT_GR15(%r1)
STREG %r16, PT_GR16(%r1)
STREG %r17, PT_GR17(%r1)
STREG %r18, PT_GR18(%r1)
STREG %r19, PT_GR19(%r1)
STREG %r20, PT_GR20(%r1)
STREG %r21, PT_GR21(%r1)
STREG %r22, PT_GR22(%r1)
STREG %r23, PT_GR23(%r1)
STREG %r24, PT_GR24(%r1)
STREG %r25, PT_GR25(%r1)
STREG %r26, PT_GR26(%r1)
STREG %r27, PT_GR27(%r1)
STREG %r28, PT_GR28(%r1)
STREG %r29, PT_GR29(%r1)
STREG %r30, PT_GR30(%r1)
STREG %r31, PT_GR31(%r1)
mfctl %cr11, %r26
STREG %r26, PT_SAR(%r1)
copy %rp, %r26
LDREG -FTRACE_FRAME_SIZE-PT_SZ_ALGN(%sp), %r25
ldo -8(%r25), %r25
ldo -FTRACE_FRAME_SIZE(%r1), %arg2
b,l ftrace_function_trampoline, %rp
copy %r1, %arg3 /* struct pt_regs */
ldo -PT_SZ_ALGN(%sp), %r1
LDREG PT_SAR(%r1), %rp
mtctl %rp, %cr11
LDREG PT_GR2(%r1), %rp
LDREG PT_GR3(%r1), %r3
LDREG PT_GR4(%r1), %r4
LDREG PT_GR5(%r1), %r5
LDREG PT_GR6(%r1), %r6
LDREG PT_GR7(%r1), %r7
LDREG PT_GR8(%r1), %r8
LDREG PT_GR9(%r1), %r9
LDREG PT_GR10(%r1),%r10
LDREG PT_GR11(%r1),%r11
LDREG PT_GR12(%r1),%r12
LDREG PT_GR13(%r1),%r13
LDREG PT_GR14(%r1),%r14
LDREG PT_GR15(%r1),%r15
LDREG PT_GR16(%r1),%r16
LDREG PT_GR17(%r1),%r17
LDREG PT_GR18(%r1),%r18
LDREG PT_GR19(%r1),%r19
LDREG PT_GR20(%r1),%r20
LDREG PT_GR21(%r1),%r21
LDREG PT_GR22(%r1),%r22
LDREG PT_GR23(%r1),%r23
LDREG PT_GR24(%r1),%r24
LDREG PT_GR25(%r1),%r25
LDREG PT_GR26(%r1),%r26
LDREG PT_GR27(%r1),%r27
LDREG PT_GR28(%r1),%r28
LDREG PT_GR29(%r1),%r29
LDREG PT_GR30(%r1),%r30
LDREG PT_GR31(%r1),%r31
ldo -PT_SZ_ALGN(%sp), %sp
LDREGM -FTRACE_FRAME_SIZE(%sp), %r1
/* Adjust return point to jump back to beginning of traced function */
ldo -4(%r1), %r1
bv,n (%r1)
ENDPROC_CFI(ftrace_regs_caller)
#endif
#endif
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
.align 8
ENTRY_CFI(return_to_handler, caller,frame=FRAME_SIZE)
.export parisc_return_to_handler,data
parisc_return_to_handler:
copy %r3,%r1
STREG %r0,-RP_OFFSET(%sp) /* store 0 as %rp */
copy %sp,%r3
STREGM %r1,FRAME_SIZE(%sp)
STREG %ret0,8(%r3)
STREG %ret1,16(%r3)
#ifdef CONFIG_64BIT
loadgp
#endif
/* call ftrace_return_to_handler(0) */
.import ftrace_return_to_handler,code
load32 ftrace_return_to_handler,%ret0
load32 .Lftrace_ret,%r2
#ifdef CONFIG_64BIT
ldo -16(%sp),%ret1 /* Reference param save area */
bve (%ret0)
#else
bv %r0(%ret0)
#endif
ldi 0,%r26
.Lftrace_ret:
copy %ret0,%rp
/* restore original return values */
LDREG 8(%r3),%ret0
LDREG 16(%r3),%ret1
/* return from function */
#ifdef CONFIG_64BIT
bve (%rp)
#else
bv %r0(%rp)
#endif
LDREGM -FRAME_SIZE(%sp),%r3
ENDPROC_CFI(return_to_handler)
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
#endif /* CONFIG_FUNCTION_TRACER */
#ifdef CONFIG_IRQSTACKS
/* void call_on_stack(unsigned long param1, void *func,
unsigned long new_stack) */
ENTRY_CFI(call_on_stack, FRAME=2*FRAME_SIZE,CALLS,SAVE_RP,SAVE_SP)
ENTRY(_call_on_stack)
copy %sp, %r1
/* Regarding the HPPA calling conventions for function pointers,
we assume the PIC register is not changed across call. For
CONFIG_64BIT, the argument pointer is left to point at the
argument region allocated for the call to call_on_stack. */
/* Switch to new stack. We allocate two frames. */
ldo 2*FRAME_SIZE(%arg2), %sp
# ifdef CONFIG_64BIT
/* Save previous stack pointer and return pointer in frame marker */
STREG %rp, -FRAME_SIZE-RP_OFFSET(%sp)
/* Calls always use function descriptor */
LDREG 16(%arg1), %arg1
bve,l (%arg1), %rp
STREG %r1, -FRAME_SIZE-REG_SZ(%sp)
LDREG -FRAME_SIZE-RP_OFFSET(%sp), %rp
bve (%rp)
LDREG -FRAME_SIZE-REG_SZ(%sp), %sp
# else
/* Save previous stack pointer and return pointer in frame marker */
STREG %r1, -FRAME_SIZE-REG_SZ(%sp)
STREG %rp, -FRAME_SIZE-RP_OFFSET(%sp)
/* Calls use function descriptor if PLABEL bit is set */
bb,>=,n %arg1, 30, 1f
depwi 0,31,2, %arg1
LDREG 0(%arg1), %arg1
1:
be,l 0(%sr4,%arg1), %sr0, %r31
copy %r31, %rp
LDREG -FRAME_SIZE-RP_OFFSET(%sp), %rp
bv (%rp)
LDREG -FRAME_SIZE-REG_SZ(%sp), %sp
# endif /* CONFIG_64BIT */
ENDPROC_CFI(call_on_stack)
#endif /* CONFIG_IRQSTACKS */
ENTRY_CFI(get_register)
/*
* 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).
*/
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
ENDPROC_CFI(get_register)
ENTRY_CFI(set_register)
/*
* set_register is used by the non access tlb miss handlers to
* copy the value of r1 into the general register specified in
* r8.
*/
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
ENDPROC_CFI(set_register)