linux/arch/ia64/kernel/ivt.S

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/*
* arch/ia64/kernel/ivt.S
*
* Copyright (C) 1998-2001, 2003, 2005 Hewlett-Packard Co
* Stephane Eranian <eranian@hpl.hp.com>
* David Mosberger <davidm@hpl.hp.com>
* Copyright (C) 2000, 2002-2003 Intel Co
* Asit Mallick <asit.k.mallick@intel.com>
* Suresh Siddha <suresh.b.siddha@intel.com>
* Kenneth Chen <kenneth.w.chen@intel.com>
* Fenghua Yu <fenghua.yu@intel.com>
*
* 00/08/23 Asit Mallick <asit.k.mallick@intel.com> TLB handling for SMP
* 00/12/20 David Mosberger-Tang <davidm@hpl.hp.com> DTLB/ITLB handler now uses virtual PT.
*/
/*
* This file defines the interruption vector table used by the CPU.
* It does not include one entry per possible cause of interruption.
*
* The first 20 entries of the table contain 64 bundles each while the
* remaining 48 entries contain only 16 bundles each.
*
* The 64 bundles are used to allow inlining the whole handler for critical
* interruptions like TLB misses.
*
* For each entry, the comment is as follows:
*
* // 0x1c00 Entry 7 (size 64 bundles) Data Key Miss (12,51)
* entry offset ----/ / / / /
* entry number ---------/ / / /
* size of the entry -------------/ / /
* vector name -------------------------------------/ /
* interruptions triggering this vector ----------------------/
*
* The table is 32KB in size and must be aligned on 32KB boundary.
* (The CPU ignores the 15 lower bits of the address)
*
* Table is based upon EAS2.6 (Oct 1999)
*/
#include <asm/asmmacro.h>
#include <asm/break.h>
#include <asm/ia32.h>
#include <asm/kregs.h>
#include <asm/asm-offsets.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
#include <asm/system.h>
#include <asm/thread_info.h>
#include <asm/unistd.h>
#include <asm/errno.h>
#if 1
# define PSR_DEFAULT_BITS psr.ac
#else
# define PSR_DEFAULT_BITS 0
#endif
#if 0
/*
* This lets you track the last eight faults that occurred on the CPU. Make sure ar.k2 isn't
* needed for something else before enabling this...
*/
# define DBG_FAULT(i) mov r16=ar.k2;; shl r16=r16,8;; add r16=(i),r16;;mov ar.k2=r16
#else
# define DBG_FAULT(i)
#endif
#include "minstate.h"
#define FAULT(n) \
mov r31=pr; \
mov r19=n;; /* prepare to save predicates */ \
br.sptk.many dispatch_to_fault_handler
.section .text.ivt,"ax"
.align 32768 // align on 32KB boundary
.global ia64_ivt
ia64_ivt:
/////////////////////////////////////////////////////////////////////////////////////////
// 0x0000 Entry 0 (size 64 bundles) VHPT Translation (8,20,47)
ENTRY(vhpt_miss)
DBG_FAULT(0)
/*
* The VHPT vector is invoked when the TLB entry for the virtual page table
* is missing. This happens only as a result of a previous
* (the "original") TLB miss, which may either be caused by an instruction
* fetch or a data access (or non-access).
*
* What we do here is normal TLB miss handing for the _original_ miss,
* followed by inserting the TLB entry for the virtual page table page
* that the VHPT walker was attempting to access. The latter gets
* inserted as long as page table entry above pte level have valid
* mappings for the faulting address. The TLB entry for the original
* miss gets inserted only if the pte entry indicates that the page is
* present.
*
* do_page_fault gets invoked in the following cases:
* - the faulting virtual address uses unimplemented address bits
* - the faulting virtual address has no valid page table mapping
*/
mov r16=cr.ifa // get address that caused the TLB miss
#ifdef CONFIG_HUGETLB_PAGE
movl r18=PAGE_SHIFT
mov r25=cr.itir
#endif
;;
rsm psr.dt // use physical addressing for data
mov r31=pr // save the predicate registers
mov r19=IA64_KR(PT_BASE) // get page table base address
shl r21=r16,3 // shift bit 60 into sign bit
shr.u r17=r16,61 // get the region number into r17
;;
shr.u r22=r21,3
#ifdef CONFIG_HUGETLB_PAGE
extr.u r26=r25,2,6
;;
cmp.ne p8,p0=r18,r26
sub r27=r26,r18
;;
(p8) dep r25=r18,r25,2,6
(p8) shr r22=r22,r27
#endif
;;
cmp.eq p6,p7=5,r17 // is IFA pointing into to region 5?
shr.u r18=r22,PGDIR_SHIFT // get bottom portion of pgd index bit
;;
(p7) dep r17=r17,r19,(PAGE_SHIFT-3),3 // put region number bits in place
srlz.d
LOAD_PHYSICAL(p6, r19, swapper_pg_dir) // region 5 is rooted at swapper_pg_dir
.pred.rel "mutex", p6, p7
(p6) shr.u r21=r21,PGDIR_SHIFT+PAGE_SHIFT
(p7) shr.u r21=r21,PGDIR_SHIFT+PAGE_SHIFT-3
;;
(p6) dep r17=r18,r19,3,(PAGE_SHIFT-3) // r17=pgd_offset for region 5
(p7) dep r17=r18,r17,3,(PAGE_SHIFT-6) // r17=pgd_offset for region[0-4]
cmp.eq p7,p6=0,r21 // unused address bits all zeroes?
#ifdef CONFIG_PGTABLE_4
shr.u r28=r22,PUD_SHIFT // shift pud index into position
#else
shr.u r18=r22,PMD_SHIFT // shift pmd index into position
#endif
;;
ld8 r17=[r17] // get *pgd (may be 0)
;;
(p7) cmp.eq p6,p7=r17,r0 // was pgd_present(*pgd) == NULL?
#ifdef CONFIG_PGTABLE_4
dep r28=r28,r17,3,(PAGE_SHIFT-3) // r28=pud_offset(pgd,addr)
;;
shr.u r18=r22,PMD_SHIFT // shift pmd index into position
(p7) ld8 r29=[r28] // get *pud (may be 0)
;;
(p7) cmp.eq.or.andcm p6,p7=r29,r0 // was pud_present(*pud) == NULL?
dep r17=r18,r29,3,(PAGE_SHIFT-3) // r17=pmd_offset(pud,addr)
#else
dep r17=r18,r17,3,(PAGE_SHIFT-3) // r17=pmd_offset(pgd,addr)
#endif
;;
(p7) ld8 r20=[r17] // get *pmd (may be 0)
shr.u r19=r22,PAGE_SHIFT // shift pte index into position
;;
(p7) cmp.eq.or.andcm p6,p7=r20,r0 // was pmd_present(*pmd) == NULL?
dep r21=r19,r20,3,(PAGE_SHIFT-3) // r21=pte_offset(pmd,addr)
;;
(p7) ld8 r18=[r21] // read *pte
mov r19=cr.isr // cr.isr bit 32 tells us if this is an insn miss
;;
(p7) tbit.z p6,p7=r18,_PAGE_P_BIT // page present bit cleared?
mov r22=cr.iha // get the VHPT address that caused the TLB miss
;; // avoid RAW on p7
(p7) tbit.nz.unc p10,p11=r19,32 // is it an instruction TLB miss?
dep r23=0,r20,0,PAGE_SHIFT // clear low bits to get page address
;;
(p10) itc.i r18 // insert the instruction TLB entry
(p11) itc.d r18 // insert the data TLB entry
(p6) br.cond.spnt.many page_fault // handle bad address/page not present (page fault)
mov cr.ifa=r22
#ifdef CONFIG_HUGETLB_PAGE
(p8) mov cr.itir=r25 // change to default page-size for VHPT
#endif
/*
* Now compute and insert the TLB entry for the virtual page table. We never
* execute in a page table page so there is no need to set the exception deferral
* bit.
*/
adds r24=__DIRTY_BITS_NO_ED|_PAGE_PL_0|_PAGE_AR_RW,r23
;;
(p7) itc.d r24
;;
#ifdef CONFIG_SMP
/*
* Tell the assemblers dependency-violation checker that the above "itc" instructions
* cannot possibly affect the following loads:
*/
dv_serialize_data
/*
* Re-check pagetable entry. If they changed, we may have received a ptc.g
* between reading the pagetable and the "itc". If so, flush the entry we
* inserted and retry. At this point, we have:
*
* r28 = equivalent of pud_offset(pgd, ifa)
* r17 = equivalent of pmd_offset(pud, ifa)
* r21 = equivalent of pte_offset(pmd, ifa)
*
* r29 = *pud
* r20 = *pmd
* r18 = *pte
*/
ld8 r25=[r21] // read *pte again
ld8 r26=[r17] // read *pmd again
#ifdef CONFIG_PGTABLE_4
ld8 r19=[r28] // read *pud again
#endif
cmp.ne p6,p7=r0,r0
;;
cmp.ne.or.andcm p6,p7=r26,r20 // did *pmd change
#ifdef CONFIG_PGTABLE_4
cmp.ne.or.andcm p6,p7=r19,r29 // did *pud change
#endif
mov r27=PAGE_SHIFT<<2
;;
(p6) ptc.l r22,r27 // purge PTE page translation
(p7) cmp.ne.or.andcm p6,p7=r25,r18 // did *pte change
;;
(p6) ptc.l r16,r27 // purge translation
#endif
mov pr=r31,-1 // restore predicate registers
rfi
END(vhpt_miss)
.org ia64_ivt+0x400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x0400 Entry 1 (size 64 bundles) ITLB (21)
ENTRY(itlb_miss)
DBG_FAULT(1)
/*
* The ITLB handler accesses the PTE via the virtually mapped linear
* page table. If a nested TLB miss occurs, we switch into physical
* mode, walk the page table, and then re-execute the PTE read and
* go on normally after that.
*/
mov r16=cr.ifa // get virtual address
mov r29=b0 // save b0
mov r31=pr // save predicates
.itlb_fault:
mov r17=cr.iha // get virtual address of PTE
movl r30=1f // load nested fault continuation point
;;
1: ld8 r18=[r17] // read *pte
;;
mov b0=r29
tbit.z p6,p0=r18,_PAGE_P_BIT // page present bit cleared?
(p6) br.cond.spnt page_fault
;;
itc.i r18
;;
#ifdef CONFIG_SMP
/*
* Tell the assemblers dependency-violation checker that the above "itc" instructions
* cannot possibly affect the following loads:
*/
dv_serialize_data
ld8 r19=[r17] // read *pte again and see if same
mov r20=PAGE_SHIFT<<2 // setup page size for purge
;;
cmp.ne p7,p0=r18,r19
;;
(p7) ptc.l r16,r20
#endif
mov pr=r31,-1
rfi
END(itlb_miss)
.org ia64_ivt+0x0800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x0800 Entry 2 (size 64 bundles) DTLB (9,48)
ENTRY(dtlb_miss)
DBG_FAULT(2)
/*
* The DTLB handler accesses the PTE via the virtually mapped linear
* page table. If a nested TLB miss occurs, we switch into physical
* mode, walk the page table, and then re-execute the PTE read and
* go on normally after that.
*/
mov r16=cr.ifa // get virtual address
mov r29=b0 // save b0
mov r31=pr // save predicates
dtlb_fault:
mov r17=cr.iha // get virtual address of PTE
movl r30=1f // load nested fault continuation point
;;
1: ld8 r18=[r17] // read *pte
;;
mov b0=r29
tbit.z p6,p0=r18,_PAGE_P_BIT // page present bit cleared?
(p6) br.cond.spnt page_fault
;;
itc.d r18
;;
#ifdef CONFIG_SMP
/*
* Tell the assemblers dependency-violation checker that the above "itc" instructions
* cannot possibly affect the following loads:
*/
dv_serialize_data
ld8 r19=[r17] // read *pte again and see if same
mov r20=PAGE_SHIFT<<2 // setup page size for purge
;;
cmp.ne p7,p0=r18,r19
;;
(p7) ptc.l r16,r20
#endif
mov pr=r31,-1
rfi
END(dtlb_miss)
.org ia64_ivt+0x0c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x0c00 Entry 3 (size 64 bundles) Alt ITLB (19)
ENTRY(alt_itlb_miss)
DBG_FAULT(3)
mov r16=cr.ifa // get address that caused the TLB miss
movl r17=PAGE_KERNEL
mov r21=cr.ipsr
movl r19=(((1 << IA64_MAX_PHYS_BITS) - 1) & ~0xfff)
mov r31=pr
;;
#ifdef CONFIG_DISABLE_VHPT
shr.u r22=r16,61 // get the region number into r21
;;
cmp.gt p8,p0=6,r22 // user mode
;;
(p8) thash r17=r16
;;
(p8) mov cr.iha=r17
(p8) mov r29=b0 // save b0
(p8) br.cond.dptk .itlb_fault
#endif
extr.u r23=r21,IA64_PSR_CPL0_BIT,2 // extract psr.cpl
and r19=r19,r16 // clear ed, reserved bits, and PTE control bits
shr.u r18=r16,57 // move address bit 61 to bit 4
;;
andcm r18=0x10,r18 // bit 4=~address-bit(61)
cmp.ne p8,p0=r0,r23 // psr.cpl != 0?
or r19=r17,r19 // insert PTE control bits into r19
;;
or r19=r19,r18 // set bit 4 (uncached) if the access was to region 6
(p8) br.cond.spnt page_fault
;;
itc.i r19 // insert the TLB entry
mov pr=r31,-1
rfi
END(alt_itlb_miss)
.org ia64_ivt+0x1000
/////////////////////////////////////////////////////////////////////////////////////////
// 0x1000 Entry 4 (size 64 bundles) Alt DTLB (7,46)
ENTRY(alt_dtlb_miss)
DBG_FAULT(4)
mov r16=cr.ifa // get address that caused the TLB miss
movl r17=PAGE_KERNEL
mov r20=cr.isr
movl r19=(((1 << IA64_MAX_PHYS_BITS) - 1) & ~0xfff)
mov r21=cr.ipsr
mov r31=pr
mov r24=PERCPU_ADDR
;;
#ifdef CONFIG_DISABLE_VHPT
shr.u r22=r16,61 // get the region number into r21
;;
cmp.gt p8,p0=6,r22 // access to region 0-5
;;
(p8) thash r17=r16
;;
(p8) mov cr.iha=r17
(p8) mov r29=b0 // save b0
(p8) br.cond.dptk dtlb_fault
#endif
cmp.ge p10,p11=r16,r24 // access to per_cpu_data?
tbit.z p12,p0=r16,61 // access to region 6?
mov r25=PERCPU_PAGE_SHIFT << 2
mov r26=PERCPU_PAGE_SIZE
nop.m 0
nop.b 0
;;
(p10) mov r19=IA64_KR(PER_CPU_DATA)
(p11) and r19=r19,r16 // clear non-ppn fields
extr.u r23=r21,IA64_PSR_CPL0_BIT,2 // extract psr.cpl
and r22=IA64_ISR_CODE_MASK,r20 // get the isr.code field
tbit.nz p6,p7=r20,IA64_ISR_SP_BIT // is speculation bit on?
tbit.nz p9,p0=r20,IA64_ISR_NA_BIT // is non-access bit on?
;;
(p10) sub r19=r19,r26
(p10) mov cr.itir=r25
cmp.ne p8,p0=r0,r23
(p9) cmp.eq.or.andcm p6,p7=IA64_ISR_CODE_LFETCH,r22 // check isr.code field
(p12) dep r17=-1,r17,4,1 // set ma=UC for region 6 addr
(p8) br.cond.spnt page_fault
dep r21=-1,r21,IA64_PSR_ED_BIT,1
;;
or r19=r19,r17 // insert PTE control bits into r19
(p6) mov cr.ipsr=r21
;;
(p7) itc.d r19 // insert the TLB entry
mov pr=r31,-1
rfi
END(alt_dtlb_miss)
.org ia64_ivt+0x1400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x1400 Entry 5 (size 64 bundles) Data nested TLB (6,45)
ENTRY(nested_dtlb_miss)
/*
* In the absence of kernel bugs, we get here when the virtually mapped linear
* page table is accessed non-speculatively (e.g., in the Dirty-bit, Instruction
* Access-bit, or Data Access-bit faults). If the DTLB entry for the virtual page
* table is missing, a nested TLB miss fault is triggered and control is
* transferred to this point. When this happens, we lookup the pte for the
* faulting address by walking the page table in physical mode and return to the
* continuation point passed in register r30 (or call page_fault if the address is
* not mapped).
*
* Input: r16: faulting address
* r29: saved b0
* r30: continuation address
* r31: saved pr
*
* Output: r17: physical address of PTE of faulting address
* r29: saved b0
* r30: continuation address
* r31: saved pr
*
* Clobbered: b0, r18, r19, r21, r22, psr.dt (cleared)
*/
rsm psr.dt // switch to using physical data addressing
mov r19=IA64_KR(PT_BASE) // get the page table base address
shl r21=r16,3 // shift bit 60 into sign bit
mov r18=cr.itir
;;
shr.u r17=r16,61 // get the region number into r17
extr.u r18=r18,2,6 // get the faulting page size
;;
cmp.eq p6,p7=5,r17 // is faulting address in region 5?
add r22=-PAGE_SHIFT,r18 // adjustment for hugetlb address
add r18=PGDIR_SHIFT-PAGE_SHIFT,r18
;;
shr.u r22=r16,r22
shr.u r18=r16,r18
(p7) dep r17=r17,r19,(PAGE_SHIFT-3),3 // put region number bits in place
srlz.d
LOAD_PHYSICAL(p6, r19, swapper_pg_dir) // region 5 is rooted at swapper_pg_dir
.pred.rel "mutex", p6, p7
(p6) shr.u r21=r21,PGDIR_SHIFT+PAGE_SHIFT
(p7) shr.u r21=r21,PGDIR_SHIFT+PAGE_SHIFT-3
;;
(p6) dep r17=r18,r19,3,(PAGE_SHIFT-3) // r17=pgd_offset for region 5
(p7) dep r17=r18,r17,3,(PAGE_SHIFT-6) // r17=pgd_offset for region[0-4]
cmp.eq p7,p6=0,r21 // unused address bits all zeroes?
#ifdef CONFIG_PGTABLE_4
shr.u r18=r22,PUD_SHIFT // shift pud index into position
#else
shr.u r18=r22,PMD_SHIFT // shift pmd index into position
#endif
;;
ld8 r17=[r17] // get *pgd (may be 0)
;;
(p7) cmp.eq p6,p7=r17,r0 // was pgd_present(*pgd) == NULL?
dep r17=r18,r17,3,(PAGE_SHIFT-3) // r17=p[u|m]d_offset(pgd,addr)
;;
#ifdef CONFIG_PGTABLE_4
(p7) ld8 r17=[r17] // get *pud (may be 0)
shr.u r18=r22,PMD_SHIFT // shift pmd index into position
;;
(p7) cmp.eq.or.andcm p6,p7=r17,r0 // was pud_present(*pud) == NULL?
dep r17=r18,r17,3,(PAGE_SHIFT-3) // r17=pmd_offset(pud,addr)
;;
#endif
(p7) ld8 r17=[r17] // get *pmd (may be 0)
shr.u r19=r22,PAGE_SHIFT // shift pte index into position
;;
(p7) cmp.eq.or.andcm p6,p7=r17,r0 // was pmd_present(*pmd) == NULL?
dep r17=r19,r17,3,(PAGE_SHIFT-3) // r17=pte_offset(pmd,addr);
(p6) br.cond.spnt page_fault
mov b0=r30
br.sptk.many b0 // return to continuation point
END(nested_dtlb_miss)
.org ia64_ivt+0x1800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x1800 Entry 6 (size 64 bundles) Instruction Key Miss (24)
ENTRY(ikey_miss)
DBG_FAULT(6)
FAULT(6)
END(ikey_miss)
//-----------------------------------------------------------------------------------
// call do_page_fault (predicates are in r31, psr.dt may be off, r16 is faulting address)
ENTRY(page_fault)
ssm psr.dt
;;
srlz.i
;;
SAVE_MIN_WITH_COVER
alloc r15=ar.pfs,0,0,3,0
mov out0=cr.ifa
mov out1=cr.isr
adds r3=8,r2 // set up second base pointer
;;
ssm psr.ic | PSR_DEFAULT_BITS
;;
srlz.i // guarantee that interruption collectin is on
;;
(p15) ssm psr.i // restore psr.i
movl r14=ia64_leave_kernel
;;
SAVE_REST
mov rp=r14
;;
adds out2=16,r12 // out2 = pointer to pt_regs
br.call.sptk.many b6=ia64_do_page_fault // ignore return address
END(page_fault)
.org ia64_ivt+0x1c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x1c00 Entry 7 (size 64 bundles) Data Key Miss (12,51)
ENTRY(dkey_miss)
DBG_FAULT(7)
FAULT(7)
END(dkey_miss)
.org ia64_ivt+0x2000
/////////////////////////////////////////////////////////////////////////////////////////
// 0x2000 Entry 8 (size 64 bundles) Dirty-bit (54)
ENTRY(dirty_bit)
DBG_FAULT(8)
/*
* What we do here is to simply turn on the dirty bit in the PTE. We need to
* update both the page-table and the TLB entry. To efficiently access the PTE,
* we address it through the virtual page table. Most likely, the TLB entry for
* the relevant virtual page table page is still present in the TLB so we can
* normally do this without additional TLB misses. In case the necessary virtual
* page table TLB entry isn't present, we take a nested TLB miss hit where we look
* up the physical address of the L3 PTE and then continue at label 1 below.
*/
mov r16=cr.ifa // get the address that caused the fault
movl r30=1f // load continuation point in case of nested fault
;;
thash r17=r16 // compute virtual address of L3 PTE
mov r29=b0 // save b0 in case of nested fault
mov r31=pr // save pr
#ifdef CONFIG_SMP
mov r28=ar.ccv // save ar.ccv
;;
1: ld8 r18=[r17]
;; // avoid RAW on r18
mov ar.ccv=r18 // set compare value for cmpxchg
or r25=_PAGE_D|_PAGE_A,r18 // set the dirty and accessed bits
tbit.z p7,p6 = r18,_PAGE_P_BIT // Check present bit
;;
(p6) cmpxchg8.acq r26=[r17],r25,ar.ccv // Only update if page is present
mov r24=PAGE_SHIFT<<2
;;
(p6) cmp.eq p6,p7=r26,r18 // Only compare if page is present
;;
(p6) itc.d r25 // install updated PTE
;;
/*
* Tell the assemblers dependency-violation checker that the above "itc" instructions
* cannot possibly affect the following loads:
*/
dv_serialize_data
ld8 r18=[r17] // read PTE again
;;
cmp.eq p6,p7=r18,r25 // is it same as the newly installed
;;
(p7) ptc.l r16,r24
mov b0=r29 // restore b0
mov ar.ccv=r28
#else
;;
1: ld8 r18=[r17]
;; // avoid RAW on r18
or r18=_PAGE_D|_PAGE_A,r18 // set the dirty and accessed bits
mov b0=r29 // restore b0
;;
st8 [r17]=r18 // store back updated PTE
itc.d r18 // install updated PTE
#endif
mov pr=r31,-1 // restore pr
rfi
END(dirty_bit)
.org ia64_ivt+0x2400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x2400 Entry 9 (size 64 bundles) Instruction Access-bit (27)
ENTRY(iaccess_bit)
DBG_FAULT(9)
// Like Entry 8, except for instruction access
mov r16=cr.ifa // get the address that caused the fault
movl r30=1f // load continuation point in case of nested fault
mov r31=pr // save predicates
#ifdef CONFIG_ITANIUM
/*
* Erratum 10 (IFA may contain incorrect address) has "NoFix" status.
*/
mov r17=cr.ipsr
;;
mov r18=cr.iip
tbit.z p6,p0=r17,IA64_PSR_IS_BIT // IA64 instruction set?
;;
(p6) mov r16=r18 // if so, use cr.iip instead of cr.ifa
#endif /* CONFIG_ITANIUM */
;;
thash r17=r16 // compute virtual address of L3 PTE
mov r29=b0 // save b0 in case of nested fault)
#ifdef CONFIG_SMP
mov r28=ar.ccv // save ar.ccv
;;
1: ld8 r18=[r17]
;;
mov ar.ccv=r18 // set compare value for cmpxchg
or r25=_PAGE_A,r18 // set the accessed bit
tbit.z p7,p6 = r18,_PAGE_P_BIT // Check present bit
;;
(p6) cmpxchg8.acq r26=[r17],r25,ar.ccv // Only if page present
mov r24=PAGE_SHIFT<<2
;;
(p6) cmp.eq p6,p7=r26,r18 // Only if page present
;;
(p6) itc.i r25 // install updated PTE
;;
/*
* Tell the assemblers dependency-violation checker that the above "itc" instructions
* cannot possibly affect the following loads:
*/
dv_serialize_data
ld8 r18=[r17] // read PTE again
;;
cmp.eq p6,p7=r18,r25 // is it same as the newly installed
;;
(p7) ptc.l r16,r24
mov b0=r29 // restore b0
mov ar.ccv=r28
#else /* !CONFIG_SMP */
;;
1: ld8 r18=[r17]
;;
or r18=_PAGE_A,r18 // set the accessed bit
mov b0=r29 // restore b0
;;
st8 [r17]=r18 // store back updated PTE
itc.i r18 // install updated PTE
#endif /* !CONFIG_SMP */
mov pr=r31,-1
rfi
END(iaccess_bit)
.org ia64_ivt+0x2800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x2800 Entry 10 (size 64 bundles) Data Access-bit (15,55)
ENTRY(daccess_bit)
DBG_FAULT(10)
// Like Entry 8, except for data access
mov r16=cr.ifa // get the address that caused the fault
movl r30=1f // load continuation point in case of nested fault
;;
thash r17=r16 // compute virtual address of L3 PTE
mov r31=pr
mov r29=b0 // save b0 in case of nested fault)
#ifdef CONFIG_SMP
mov r28=ar.ccv // save ar.ccv
;;
1: ld8 r18=[r17]
;; // avoid RAW on r18
mov ar.ccv=r18 // set compare value for cmpxchg
or r25=_PAGE_A,r18 // set the dirty bit
tbit.z p7,p6 = r18,_PAGE_P_BIT // Check present bit
;;
(p6) cmpxchg8.acq r26=[r17],r25,ar.ccv // Only if page is present
mov r24=PAGE_SHIFT<<2
;;
(p6) cmp.eq p6,p7=r26,r18 // Only if page is present
;;
(p6) itc.d r25 // install updated PTE
/*
* Tell the assemblers dependency-violation checker that the above "itc" instructions
* cannot possibly affect the following loads:
*/
dv_serialize_data
;;
ld8 r18=[r17] // read PTE again
;;
cmp.eq p6,p7=r18,r25 // is it same as the newly installed
;;
(p7) ptc.l r16,r24
mov ar.ccv=r28
#else
;;
1: ld8 r18=[r17]
;; // avoid RAW on r18
or r18=_PAGE_A,r18 // set the accessed bit
;;
st8 [r17]=r18 // store back updated PTE
itc.d r18 // install updated PTE
#endif
mov b0=r29 // restore b0
mov pr=r31,-1
rfi
END(daccess_bit)
.org ia64_ivt+0x2c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x2c00 Entry 11 (size 64 bundles) Break instruction (33)
ENTRY(break_fault)
/*
* The streamlined system call entry/exit paths only save/restore the initial part
* of pt_regs. This implies that the callers of system-calls must adhere to the
* normal procedure calling conventions.
*
* Registers to be saved & restored:
* CR registers: cr.ipsr, cr.iip, cr.ifs
* AR registers: ar.unat, ar.pfs, ar.rsc, ar.rnat, ar.bspstore, ar.fpsr
* others: pr, b0, b6, loadrs, r1, r11, r12, r13, r15
* Registers to be restored only:
* r8-r11: output value from the system call.
*
* During system call exit, scratch registers (including r15) are modified/cleared
* to prevent leaking bits from kernel to user level.
*/
DBG_FAULT(11)
mov.m r16=IA64_KR(CURRENT) // M2 r16 <- current task (12 cyc)
mov r29=cr.ipsr // M2 (12 cyc)
mov r31=pr // I0 (2 cyc)
mov r17=cr.iim // M2 (2 cyc)
mov.m r27=ar.rsc // M2 (12 cyc)
mov r18=__IA64_BREAK_SYSCALL // A
mov.m ar.rsc=0 // M2
mov.m r21=ar.fpsr // M2 (12 cyc)
mov r19=b6 // I0 (2 cyc)
;;
mov.m r23=ar.bspstore // M2 (12 cyc)
mov.m r24=ar.rnat // M2 (5 cyc)
mov.i r26=ar.pfs // I0 (2 cyc)
invala // M0|1
nop.m 0 // M
mov r20=r1 // A save r1
nop.m 0
movl r30=sys_call_table // X
mov r28=cr.iip // M2 (2 cyc)
cmp.eq p0,p7=r18,r17 // I0 is this a system call?
(p7) br.cond.spnt non_syscall // B no ->
//
// From this point on, we are definitely on the syscall-path
// and we can use (non-banked) scratch registers.
//
///////////////////////////////////////////////////////////////////////
mov r1=r16 // A move task-pointer to "addl"-addressable reg
mov r2=r16 // A setup r2 for ia64_syscall_setup
add r9=TI_FLAGS+IA64_TASK_SIZE,r16 // A r9 = &current_thread_info()->flags
adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16
adds r15=-1024,r15 // A subtract 1024 from syscall number
mov r3=NR_syscalls - 1
;;
ld1.bias r17=[r16] // M0|1 r17 = current->thread.on_ustack flag
ld4 r9=[r9] // M0|1 r9 = current_thread_info()->flags
extr.u r8=r29,41,2 // I0 extract ei field from cr.ipsr
shladd r30=r15,3,r30 // A r30 = sys_call_table + 8*(syscall-1024)
addl r22=IA64_RBS_OFFSET,r1 // A compute base of RBS
cmp.leu p6,p7=r15,r3 // A syscall number in range?
;;
lfetch.fault.excl.nt1 [r22] // M0|1 prefetch RBS
(p6) ld8 r30=[r30] // M0|1 load address of syscall entry point
tnat.nz.or p7,p0=r15 // I0 is syscall nr a NaT?
mov.m ar.bspstore=r22 // M2 switch to kernel RBS
cmp.eq p8,p9=2,r8 // A isr.ei==2?
;;
(p8) mov r8=0 // A clear ei to 0
(p7) movl r30=sys_ni_syscall // X
(p8) adds r28=16,r28 // A switch cr.iip to next bundle
(p9) adds r8=1,r8 // A increment ei to next slot
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
;;
mov b6=r30 // I0 setup syscall handler branch reg early
#else
nop.i 0
;;
#endif
mov.m r25=ar.unat // M2 (5 cyc)
dep r29=r8,r29,41,2 // I0 insert new ei into cr.ipsr
adds r15=1024,r15 // A restore original syscall number
//
// If any of the above loads miss in L1D, we'll stall here until
// the data arrives.
//
///////////////////////////////////////////////////////////////////////
st1 [r16]=r0 // M2|3 clear current->thread.on_ustack flag
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
mov.m r30=ar.itc // M get cycle for accounting
#else
mov b6=r30 // I0 setup syscall handler branch reg early
#endif
cmp.eq pKStk,pUStk=r0,r17 // A were we on kernel stacks already?
and r9=_TIF_SYSCALL_TRACEAUDIT,r9 // A mask trace or audit
mov r18=ar.bsp // M2 (12 cyc)
(pKStk) br.cond.spnt .break_fixup // B we're already in kernel-mode -- fix up RBS
;;
.back_from_break_fixup:
(pUStk) addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r1 // A compute base of memory stack
cmp.eq p14,p0=r9,r0 // A are syscalls being traced/audited?
br.call.sptk.many b7=ia64_syscall_setup // B
1:
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
// mov.m r30=ar.itc is called in advance, and r13 is current
add r16=TI_AC_STAMP+IA64_TASK_SIZE,r13 // A
add r17=TI_AC_LEAVE+IA64_TASK_SIZE,r13 // A
(pKStk) br.cond.spnt .skip_accounting // B unlikely skip
;;
ld8 r18=[r16],TI_AC_STIME-TI_AC_STAMP // M get last stamp
ld8 r19=[r17],TI_AC_UTIME-TI_AC_LEAVE // M time at leave
;;
ld8 r20=[r16],TI_AC_STAMP-TI_AC_STIME // M cumulated stime
ld8 r21=[r17] // M cumulated utime
sub r22=r19,r18 // A stime before leave
;;
st8 [r16]=r30,TI_AC_STIME-TI_AC_STAMP // M update stamp
sub r18=r30,r19 // A elapsed time in user
;;
add r20=r20,r22 // A sum stime
add r21=r21,r18 // A sum utime
;;
st8 [r16]=r20 // M update stime
st8 [r17]=r21 // M update utime
;;
.skip_accounting:
#endif
mov ar.rsc=0x3 // M2 set eager mode, pl 0, LE, loadrs=0
nop 0
bsw.1 // B (6 cyc) regs are saved, switch to bank 1
;;
ssm psr.ic | PSR_DEFAULT_BITS // M2 now it's safe to re-enable intr.-collection
movl r3=ia64_ret_from_syscall // X
;;
srlz.i // M0 ensure interruption collection is on
mov rp=r3 // I0 set the real return addr
(p10) br.cond.spnt.many ia64_ret_from_syscall // B return if bad call-frame or r15 is a NaT
(p15) ssm psr.i // M2 restore psr.i
(p14) br.call.sptk.many b6=b6 // B invoke syscall-handker (ignore return addr)
br.cond.spnt.many ia64_trace_syscall // B do syscall-tracing thingamagic
// NOT REACHED
///////////////////////////////////////////////////////////////////////
// On entry, we optimistically assumed that we're coming from user-space.
// For the rare cases where a system-call is done from within the kernel,
// we fix things up at this point:
.break_fixup:
add r1=-IA64_PT_REGS_SIZE,sp // A allocate space for pt_regs structure
mov ar.rnat=r24 // M2 restore kernel's AR.RNAT
;;
mov ar.bspstore=r23 // M2 restore kernel's AR.BSPSTORE
br.cond.sptk .back_from_break_fixup
END(break_fault)
.org ia64_ivt+0x3000
/////////////////////////////////////////////////////////////////////////////////////////
// 0x3000 Entry 12 (size 64 bundles) External Interrupt (4)
ENTRY(interrupt)
DBG_FAULT(12)
mov r31=pr // prepare to save predicates
;;
SAVE_MIN_WITH_COVER // uses r31; defines r2 and r3
ssm psr.ic | PSR_DEFAULT_BITS
;;
adds r3=8,r2 // set up second base pointer for SAVE_REST
srlz.i // ensure everybody knows psr.ic is back on
;;
SAVE_REST
;;
[IA64] MCA recovery: kernel context recovery table Memory errors encountered by user applications may surface when the CPU is running in kernel context. The current code will not attempt recovery if the MCA surfaces in kernel context (privilage mode 0). This patch adds a check for cases where the user initiated the load that surfaces in kernel interrupt code. An example is a user process lauching a load from memory and the data in memory had bad ECC. Before the bad data gets to the CPU register, and interrupt comes in. The code jumps to the IVT interrupt entry point and begins execution in kernel context. The process of saving the user registers (SAVE_REST) causes the bad data to be loaded into a CPU register, triggering the MCA. The MCA surfaces in kernel context, even though the load was initiated from user context. As suggested by David and Tony, this patch uses an exception table like approach, puting the tagged recovery addresses in a searchable table. One difference from the exception table is that MCAs do not surface in precise places (such as with a TLB miss), so instead of tagging specific instructions, address ranges are registers. A single macro is used to do the tagging, with the input parameter being the label of the starting address and the macro being the ending address. This limits clutter in the code. This patch only tags one spot, the interrupt ivt entry. Testing showed that spot to be a "heavy hitter" with MCAs surfacing while saving user registers. Other spots can be added as needed by adding a single macro. Signed-off-by: Russ Anderson (rja@sgi.com) Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-24 17:49:52 +00:00
MCA_RECOVER_RANGE(interrupt)
alloc r14=ar.pfs,0,0,2,0 // must be first in an insn group
mov out0=cr.ivr // pass cr.ivr as first arg
add out1=16,sp // pass pointer to pt_regs as second arg
;;
srlz.d // make sure we see the effect of cr.ivr
movl r14=ia64_leave_kernel
;;
mov rp=r14
br.call.sptk.many b6=ia64_handle_irq
END(interrupt)
.org ia64_ivt+0x3400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x3400 Entry 13 (size 64 bundles) Reserved
DBG_FAULT(13)
FAULT(13)
.org ia64_ivt+0x3800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x3800 Entry 14 (size 64 bundles) Reserved
DBG_FAULT(14)
FAULT(14)
/*
* There is no particular reason for this code to be here, other than that
* there happens to be space here that would go unused otherwise. If this
* fault ever gets "unreserved", simply moved the following code to a more
* suitable spot...
*
* ia64_syscall_setup() is a separate subroutine so that it can
* allocate stacked registers so it can safely demine any
* potential NaT values from the input registers.
*
* On entry:
* - executing on bank 0 or bank 1 register set (doesn't matter)
* - r1: stack pointer
* - r2: current task pointer
* - r3: preserved
* - r11: original contents (saved ar.pfs to be saved)
* - r12: original contents (sp to be saved)
* - r13: original contents (tp to be saved)
* - r15: original contents (syscall # to be saved)
* - r18: saved bsp (after switching to kernel stack)
* - r19: saved b6
* - r20: saved r1 (gp)
* - r21: saved ar.fpsr
* - r22: kernel's register backing store base (krbs_base)
* - r23: saved ar.bspstore
* - r24: saved ar.rnat
* - r25: saved ar.unat
* - r26: saved ar.pfs
* - r27: saved ar.rsc
* - r28: saved cr.iip
* - r29: saved cr.ipsr
* - r30: ar.itc for accounting (don't touch)
* - r31: saved pr
* - b0: original contents (to be saved)
* On exit:
* - p10: TRUE if syscall is invoked with more than 8 out
* registers or r15's Nat is true
* - r1: kernel's gp
* - r3: preserved (same as on entry)
* - r8: -EINVAL if p10 is true
* - r12: points to kernel stack
* - r13: points to current task
* - r14: preserved (same as on entry)
* - p13: preserved
* - p15: TRUE if interrupts need to be re-enabled
* - ar.fpsr: set to kernel settings
* - b6: preserved (same as on entry)
*/
GLOBAL_ENTRY(ia64_syscall_setup)
#if PT(B6) != 0
# error This code assumes that b6 is the first field in pt_regs.
#endif
st8 [r1]=r19 // save b6
add r16=PT(CR_IPSR),r1 // initialize first base pointer
add r17=PT(R11),r1 // initialize second base pointer
;;
alloc r19=ar.pfs,8,0,0,0 // ensure in0-in7 are writable
st8 [r16]=r29,PT(AR_PFS)-PT(CR_IPSR) // save cr.ipsr
tnat.nz p8,p0=in0
st8.spill [r17]=r11,PT(CR_IIP)-PT(R11) // save r11
tnat.nz p9,p0=in1
(pKStk) mov r18=r0 // make sure r18 isn't NaT
;;
st8 [r16]=r26,PT(CR_IFS)-PT(AR_PFS) // save ar.pfs
st8 [r17]=r28,PT(AR_UNAT)-PT(CR_IIP) // save cr.iip
mov r28=b0 // save b0 (2 cyc)
;;
st8 [r17]=r25,PT(AR_RSC)-PT(AR_UNAT) // save ar.unat
dep r19=0,r19,38,26 // clear all bits but 0..37 [I0]
(p8) mov in0=-1
;;
st8 [r16]=r19,PT(AR_RNAT)-PT(CR_IFS) // store ar.pfs.pfm in cr.ifs
extr.u r11=r19,7,7 // I0 // get sol of ar.pfs
and r8=0x7f,r19 // A // get sof of ar.pfs
st8 [r17]=r27,PT(AR_BSPSTORE)-PT(AR_RSC)// save ar.rsc
tbit.nz p15,p0=r29,IA64_PSR_I_BIT // I0
(p9) mov in1=-1
;;
(pUStk) sub r18=r18,r22 // r18=RSE.ndirty*8
tnat.nz p10,p0=in2
add r11=8,r11
;;
(pKStk) adds r16=PT(PR)-PT(AR_RNAT),r16 // skip over ar_rnat field
(pKStk) adds r17=PT(B0)-PT(AR_BSPSTORE),r17 // skip over ar_bspstore field
tnat.nz p11,p0=in3
;;
(p10) mov in2=-1
tnat.nz p12,p0=in4 // [I0]
(p11) mov in3=-1
;;
(pUStk) st8 [r16]=r24,PT(PR)-PT(AR_RNAT) // save ar.rnat
(pUStk) st8 [r17]=r23,PT(B0)-PT(AR_BSPSTORE) // save ar.bspstore
shl r18=r18,16 // compute ar.rsc to be used for "loadrs"
;;
st8 [r16]=r31,PT(LOADRS)-PT(PR) // save predicates
st8 [r17]=r28,PT(R1)-PT(B0) // save b0
tnat.nz p13,p0=in5 // [I0]
;;
st8 [r16]=r18,PT(R12)-PT(LOADRS) // save ar.rsc value for "loadrs"
st8.spill [r17]=r20,PT(R13)-PT(R1) // save original r1
(p12) mov in4=-1
;;
.mem.offset 0,0; st8.spill [r16]=r12,PT(AR_FPSR)-PT(R12) // save r12
.mem.offset 8,0; st8.spill [r17]=r13,PT(R15)-PT(R13) // save r13
(p13) mov in5=-1
;;
st8 [r16]=r21,PT(R8)-PT(AR_FPSR) // save ar.fpsr
tnat.nz p13,p0=in6
cmp.lt p10,p9=r11,r8 // frame size can't be more than local+8
;;
mov r8=1
(p9) tnat.nz p10,p0=r15
adds r12=-16,r1 // switch to kernel memory stack (with 16 bytes of scratch)
st8.spill [r17]=r15 // save r15
tnat.nz p8,p0=in7
nop.i 0
mov r13=r2 // establish `current'
movl r1=__gp // establish kernel global pointer
;;
st8 [r16]=r8 // ensure pt_regs.r8 != 0 (see handle_syscall_error)
(p13) mov in6=-1
(p8) mov in7=-1
cmp.eq pSys,pNonSys=r0,r0 // set pSys=1, pNonSys=0
movl r17=FPSR_DEFAULT
;;
mov.m ar.fpsr=r17 // set ar.fpsr to kernel default value
(p10) mov r8=-EINVAL
br.ret.sptk.many b7
END(ia64_syscall_setup)
.org ia64_ivt+0x3c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x3c00 Entry 15 (size 64 bundles) Reserved
DBG_FAULT(15)
FAULT(15)
.org ia64_ivt+0x4000
/////////////////////////////////////////////////////////////////////////////////////////
// 0x4000 Entry 16 (size 64 bundles) Reserved
DBG_FAULT(16)
FAULT(16)
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
/*
* There is no particular reason for this code to be here, other than
* that there happens to be space here that would go unused otherwise.
* If this fault ever gets "unreserved", simply moved the following
* code to a more suitable spot...
*
* account_sys_enter is called from SAVE_MIN* macros if accounting is
* enabled and if the macro is entered from user mode.
*/
ENTRY(account_sys_enter)
// mov.m r20=ar.itc is called in advance, and r13 is current
add r16=TI_AC_STAMP+IA64_TASK_SIZE,r13
add r17=TI_AC_LEAVE+IA64_TASK_SIZE,r13
;;
ld8 r18=[r16],TI_AC_STIME-TI_AC_STAMP // time at last check in kernel
ld8 r19=[r17],TI_AC_UTIME-TI_AC_LEAVE // time at left from kernel
;;
ld8 r23=[r16],TI_AC_STAMP-TI_AC_STIME // cumulated stime
ld8 r21=[r17] // cumulated utime
sub r22=r19,r18 // stime before leave kernel
;;
st8 [r16]=r20,TI_AC_STIME-TI_AC_STAMP // update stamp
sub r18=r20,r19 // elapsed time in user mode
;;
add r23=r23,r22 // sum stime
add r21=r21,r18 // sum utime
;;
st8 [r16]=r23 // update stime
st8 [r17]=r21 // update utime
;;
br.ret.sptk.many rp
END(account_sys_enter)
#endif
.org ia64_ivt+0x4400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x4400 Entry 17 (size 64 bundles) Reserved
DBG_FAULT(17)
FAULT(17)
ENTRY(non_syscall)
mov ar.rsc=r27 // restore ar.rsc before SAVE_MIN_WITH_COVER
;;
SAVE_MIN_WITH_COVER
// There is no particular reason for this code to be here, other than that
// there happens to be space here that would go unused otherwise. If this
// fault ever gets "unreserved", simply moved the following code to a more
// suitable spot...
alloc r14=ar.pfs,0,0,2,0
mov out0=cr.iim
add out1=16,sp
adds r3=8,r2 // set up second base pointer for SAVE_REST
ssm psr.ic | PSR_DEFAULT_BITS
;;
srlz.i // guarantee that interruption collection is on
;;
(p15) ssm psr.i // restore psr.i
movl r15=ia64_leave_kernel
;;
SAVE_REST
mov rp=r15
;;
br.call.sptk.many b6=ia64_bad_break // avoid WAW on CFM and ignore return addr
END(non_syscall)
.org ia64_ivt+0x4800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x4800 Entry 18 (size 64 bundles) Reserved
DBG_FAULT(18)
FAULT(18)
/*
* There is no particular reason for this code to be here, other than that
* there happens to be space here that would go unused otherwise. If this
* fault ever gets "unreserved", simply moved the following code to a more
* suitable spot...
*/
ENTRY(dispatch_unaligned_handler)
SAVE_MIN_WITH_COVER
;;
alloc r14=ar.pfs,0,0,2,0 // now it's safe (must be first in insn group!)
mov out0=cr.ifa
adds out1=16,sp
ssm psr.ic | PSR_DEFAULT_BITS
;;
srlz.i // guarantee that interruption collection is on
;;
(p15) ssm psr.i // restore psr.i
adds r3=8,r2 // set up second base pointer
;;
SAVE_REST
movl r14=ia64_leave_kernel
;;
mov rp=r14
br.sptk.many ia64_prepare_handle_unaligned
END(dispatch_unaligned_handler)
.org ia64_ivt+0x4c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x4c00 Entry 19 (size 64 bundles) Reserved
DBG_FAULT(19)
FAULT(19)
/*
* There is no particular reason for this code to be here, other than that
* there happens to be space here that would go unused otherwise. If this
* fault ever gets "unreserved", simply moved the following code to a more
* suitable spot...
*/
ENTRY(dispatch_to_fault_handler)
/*
* Input:
* psr.ic: off
* r19: fault vector number (e.g., 24 for General Exception)
* r31: contains saved predicates (pr)
*/
SAVE_MIN_WITH_COVER_R19
alloc r14=ar.pfs,0,0,5,0
mov out0=r15
mov out1=cr.isr
mov out2=cr.ifa
mov out3=cr.iim
mov out4=cr.itir
;;
ssm psr.ic | PSR_DEFAULT_BITS
;;
srlz.i // guarantee that interruption collection is on
;;
(p15) ssm psr.i // restore psr.i
adds r3=8,r2 // set up second base pointer for SAVE_REST
;;
SAVE_REST
movl r14=ia64_leave_kernel
;;
mov rp=r14
br.call.sptk.many b6=ia64_fault
END(dispatch_to_fault_handler)
//
// --- End of long entries, Beginning of short entries
//
.org ia64_ivt+0x5000
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5000 Entry 20 (size 16 bundles) Page Not Present (10,22,49)
ENTRY(page_not_present)
DBG_FAULT(20)
mov r16=cr.ifa
rsm psr.dt
/*
* The Linux page fault handler doesn't expect non-present pages to be in
* the TLB. Flush the existing entry now, so we meet that expectation.
*/
mov r17=PAGE_SHIFT<<2
;;
ptc.l r16,r17
;;
mov r31=pr
srlz.d
br.sptk.many page_fault
END(page_not_present)
.org ia64_ivt+0x5100
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5100 Entry 21 (size 16 bundles) Key Permission (13,25,52)
ENTRY(key_permission)
DBG_FAULT(21)
mov r16=cr.ifa
rsm psr.dt
mov r31=pr
;;
srlz.d
br.sptk.many page_fault
END(key_permission)
.org ia64_ivt+0x5200
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5200 Entry 22 (size 16 bundles) Instruction Access Rights (26)
ENTRY(iaccess_rights)
DBG_FAULT(22)
mov r16=cr.ifa
rsm psr.dt
mov r31=pr
;;
srlz.d
br.sptk.many page_fault
END(iaccess_rights)
.org ia64_ivt+0x5300
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5300 Entry 23 (size 16 bundles) Data Access Rights (14,53)
ENTRY(daccess_rights)
DBG_FAULT(23)
mov r16=cr.ifa
rsm psr.dt
mov r31=pr
;;
srlz.d
br.sptk.many page_fault
END(daccess_rights)
.org ia64_ivt+0x5400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5400 Entry 24 (size 16 bundles) General Exception (5,32,34,36,38,39)
ENTRY(general_exception)
DBG_FAULT(24)
mov r16=cr.isr
mov r31=pr
;;
cmp4.eq p6,p0=0,r16
(p6) br.sptk.many dispatch_illegal_op_fault
;;
mov r19=24 // fault number
br.sptk.many dispatch_to_fault_handler
END(general_exception)
.org ia64_ivt+0x5500
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5500 Entry 25 (size 16 bundles) Disabled FP-Register (35)
ENTRY(disabled_fp_reg)
DBG_FAULT(25)
rsm psr.dfh // ensure we can access fph
;;
srlz.d
mov r31=pr
mov r19=25
br.sptk.many dispatch_to_fault_handler
END(disabled_fp_reg)
.org ia64_ivt+0x5600
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5600 Entry 26 (size 16 bundles) Nat Consumption (11,23,37,50)
ENTRY(nat_consumption)
DBG_FAULT(26)
mov r16=cr.ipsr
mov r17=cr.isr
mov r31=pr // save PR
;;
and r18=0xf,r17 // r18 = cr.ipsr.code{3:0}
tbit.z p6,p0=r17,IA64_ISR_NA_BIT
;;
cmp.ne.or p6,p0=IA64_ISR_CODE_LFETCH,r18
dep r16=-1,r16,IA64_PSR_ED_BIT,1
(p6) br.cond.spnt 1f // branch if (cr.ispr.na == 0 || cr.ipsr.code{3:0} != LFETCH)
;;
mov cr.ipsr=r16 // set cr.ipsr.na
mov pr=r31,-1
;;
rfi
1: mov pr=r31,-1
;;
FAULT(26)
END(nat_consumption)
.org ia64_ivt+0x5700
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5700 Entry 27 (size 16 bundles) Speculation (40)
ENTRY(speculation_vector)
DBG_FAULT(27)
/*
* A [f]chk.[as] instruction needs to take the branch to the recovery code but
* this part of the architecture is not implemented in hardware on some CPUs, such
* as Itanium. Thus, in general we need to emulate the behavior. IIM contains
* the relative target (not yet sign extended). So after sign extending it we
* simply add it to IIP. We also need to reset the EI field of the IPSR to zero,
* i.e., the slot to restart into.
*
* cr.imm contains zero_ext(imm21)
*/
mov r18=cr.iim
;;
mov r17=cr.iip
shl r18=r18,43 // put sign bit in position (43=64-21)
;;
mov r16=cr.ipsr
shr r18=r18,39 // sign extend (39=43-4)
;;
add r17=r17,r18 // now add the offset
;;
mov cr.iip=r17
dep r16=0,r16,41,2 // clear EI
;;
mov cr.ipsr=r16
;;
rfi // and go back
END(speculation_vector)
.org ia64_ivt+0x5800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5800 Entry 28 (size 16 bundles) Reserved
DBG_FAULT(28)
FAULT(28)
.org ia64_ivt+0x5900
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5900 Entry 29 (size 16 bundles) Debug (16,28,56)
ENTRY(debug_vector)
DBG_FAULT(29)
FAULT(29)
END(debug_vector)
.org ia64_ivt+0x5a00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5a00 Entry 30 (size 16 bundles) Unaligned Reference (57)
ENTRY(unaligned_access)
DBG_FAULT(30)
mov r31=pr // prepare to save predicates
;;
br.sptk.many dispatch_unaligned_handler
END(unaligned_access)
.org ia64_ivt+0x5b00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5b00 Entry 31 (size 16 bundles) Unsupported Data Reference (57)
ENTRY(unsupported_data_reference)
DBG_FAULT(31)
FAULT(31)
END(unsupported_data_reference)
.org ia64_ivt+0x5c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5c00 Entry 32 (size 16 bundles) Floating-Point Fault (64)
ENTRY(floating_point_fault)
DBG_FAULT(32)
FAULT(32)
END(floating_point_fault)
.org ia64_ivt+0x5d00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5d00 Entry 33 (size 16 bundles) Floating Point Trap (66)
ENTRY(floating_point_trap)
DBG_FAULT(33)
FAULT(33)
END(floating_point_trap)
.org ia64_ivt+0x5e00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5e00 Entry 34 (size 16 bundles) Lower Privilege Transfer Trap (66)
ENTRY(lower_privilege_trap)
DBG_FAULT(34)
FAULT(34)
END(lower_privilege_trap)
.org ia64_ivt+0x5f00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x5f00 Entry 35 (size 16 bundles) Taken Branch Trap (68)
ENTRY(taken_branch_trap)
DBG_FAULT(35)
FAULT(35)
END(taken_branch_trap)
.org ia64_ivt+0x6000
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6000 Entry 36 (size 16 bundles) Single Step Trap (69)
ENTRY(single_step_trap)
DBG_FAULT(36)
FAULT(36)
END(single_step_trap)
.org ia64_ivt+0x6100
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6100 Entry 37 (size 16 bundles) Reserved
DBG_FAULT(37)
FAULT(37)
.org ia64_ivt+0x6200
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6200 Entry 38 (size 16 bundles) Reserved
DBG_FAULT(38)
FAULT(38)
.org ia64_ivt+0x6300
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6300 Entry 39 (size 16 bundles) Reserved
DBG_FAULT(39)
FAULT(39)
.org ia64_ivt+0x6400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6400 Entry 40 (size 16 bundles) Reserved
DBG_FAULT(40)
FAULT(40)
.org ia64_ivt+0x6500
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6500 Entry 41 (size 16 bundles) Reserved
DBG_FAULT(41)
FAULT(41)
.org ia64_ivt+0x6600
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6600 Entry 42 (size 16 bundles) Reserved
DBG_FAULT(42)
FAULT(42)
.org ia64_ivt+0x6700
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6700 Entry 43 (size 16 bundles) Reserved
DBG_FAULT(43)
FAULT(43)
.org ia64_ivt+0x6800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6800 Entry 44 (size 16 bundles) Reserved
DBG_FAULT(44)
FAULT(44)
.org ia64_ivt+0x6900
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6900 Entry 45 (size 16 bundles) IA-32 Exeception (17,18,29,41,42,43,44,58,60,61,62,72,73,75,76,77)
ENTRY(ia32_exception)
DBG_FAULT(45)
FAULT(45)
END(ia32_exception)
.org ia64_ivt+0x6a00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6a00 Entry 46 (size 16 bundles) IA-32 Intercept (30,31,59,70,71)
ENTRY(ia32_intercept)
DBG_FAULT(46)
#ifdef CONFIG_IA32_SUPPORT
mov r31=pr
mov r16=cr.isr
;;
extr.u r17=r16,16,8 // get ISR.code
mov r18=ar.eflag
mov r19=cr.iim // old eflag value
;;
cmp.ne p6,p0=2,r17
(p6) br.cond.spnt 1f // not a system flag fault
xor r16=r18,r19
;;
extr.u r17=r16,18,1 // get the eflags.ac bit
;;
cmp.eq p6,p0=0,r17
(p6) br.cond.spnt 1f // eflags.ac bit didn't change
;;
mov pr=r31,-1 // restore predicate registers
rfi
1:
#endif // CONFIG_IA32_SUPPORT
FAULT(46)
END(ia32_intercept)
.org ia64_ivt+0x6b00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6b00 Entry 47 (size 16 bundles) IA-32 Interrupt (74)
ENTRY(ia32_interrupt)
DBG_FAULT(47)
#ifdef CONFIG_IA32_SUPPORT
mov r31=pr
br.sptk.many dispatch_to_ia32_handler
#else
FAULT(47)
#endif
END(ia32_interrupt)
.org ia64_ivt+0x6c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6c00 Entry 48 (size 16 bundles) Reserved
DBG_FAULT(48)
FAULT(48)
.org ia64_ivt+0x6d00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6d00 Entry 49 (size 16 bundles) Reserved
DBG_FAULT(49)
FAULT(49)
.org ia64_ivt+0x6e00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6e00 Entry 50 (size 16 bundles) Reserved
DBG_FAULT(50)
FAULT(50)
.org ia64_ivt+0x6f00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x6f00 Entry 51 (size 16 bundles) Reserved
DBG_FAULT(51)
FAULT(51)
.org ia64_ivt+0x7000
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7000 Entry 52 (size 16 bundles) Reserved
DBG_FAULT(52)
FAULT(52)
.org ia64_ivt+0x7100
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7100 Entry 53 (size 16 bundles) Reserved
DBG_FAULT(53)
FAULT(53)
.org ia64_ivt+0x7200
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7200 Entry 54 (size 16 bundles) Reserved
DBG_FAULT(54)
FAULT(54)
.org ia64_ivt+0x7300
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7300 Entry 55 (size 16 bundles) Reserved
DBG_FAULT(55)
FAULT(55)
.org ia64_ivt+0x7400
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7400 Entry 56 (size 16 bundles) Reserved
DBG_FAULT(56)
FAULT(56)
.org ia64_ivt+0x7500
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7500 Entry 57 (size 16 bundles) Reserved
DBG_FAULT(57)
FAULT(57)
.org ia64_ivt+0x7600
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7600 Entry 58 (size 16 bundles) Reserved
DBG_FAULT(58)
FAULT(58)
.org ia64_ivt+0x7700
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7700 Entry 59 (size 16 bundles) Reserved
DBG_FAULT(59)
FAULT(59)
.org ia64_ivt+0x7800
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7800 Entry 60 (size 16 bundles) Reserved
DBG_FAULT(60)
FAULT(60)
.org ia64_ivt+0x7900
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7900 Entry 61 (size 16 bundles) Reserved
DBG_FAULT(61)
FAULT(61)
.org ia64_ivt+0x7a00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7a00 Entry 62 (size 16 bundles) Reserved
DBG_FAULT(62)
FAULT(62)
.org ia64_ivt+0x7b00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7b00 Entry 63 (size 16 bundles) Reserved
DBG_FAULT(63)
FAULT(63)
.org ia64_ivt+0x7c00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7c00 Entry 64 (size 16 bundles) Reserved
DBG_FAULT(64)
FAULT(64)
.org ia64_ivt+0x7d00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7d00 Entry 65 (size 16 bundles) Reserved
DBG_FAULT(65)
FAULT(65)
.org ia64_ivt+0x7e00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7e00 Entry 66 (size 16 bundles) Reserved
DBG_FAULT(66)
FAULT(66)
.org ia64_ivt+0x7f00
/////////////////////////////////////////////////////////////////////////////////////////
// 0x7f00 Entry 67 (size 16 bundles) Reserved
DBG_FAULT(67)
FAULT(67)
[IA64] Workaround for RSE issue Problem: An application violating the architectural rules regarding operation dependencies and having specific Register Stack Engine (RSE) state at the time of the violation, may result in an illegal operation fault and invalid RSE state. Such faults may initiate a cascade of repeated illegal operation faults within OS interruption handlers. The specific behavior is OS dependent. Implication: An application causing an illegal operation fault with specific RSE state may result in a series of illegal operation faults and an eventual OS stack overflow condition. Workaround: OS interruption handlers that switch to kernel backing store implement a check for invalid RSE state to avoid the series of illegal operation faults. The core of the workaround is the RSE_WORKAROUND code sequence inserted into each invocation of the SAVE_MIN_WITH_COVER and SAVE_MIN_WITH_COVER_R19 macros. This sequence includes hard-coded constants that depend on the number of stacked physical registers being 96. The rest of this patch consists of code to disable this workaround should this not be the case (with the presumption that if a future Itanium processor increases the number of registers, it would also remove the need for this patch). Move the start of the RBS up to a mod32 boundary to avoid some corner cases. The dispatch_illegal_op_fault code outgrew the spot it was squatting in when built with this patch and CONFIG_VIRT_CPU_ACCOUNTING=y Move it out to the end of the ivt. Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-05-27 20:23:16 +00:00
/*
* Squatting in this space ...
*
* This special case dispatcher for illegal operation faults allows preserved
* registers to be modified through a callback function (asm only) that is handed
* back from the fault handler in r8. Up to three arguments can be passed to the
* callback function by returning an aggregate with the callback as its first
* element, followed by the arguments.
*/
ENTRY(dispatch_illegal_op_fault)
.prologue
.body
SAVE_MIN_WITH_COVER
ssm psr.ic | PSR_DEFAULT_BITS
;;
srlz.i // guarantee that interruption collection is on
;;
(p15) ssm psr.i // restore psr.i
adds r3=8,r2 // set up second base pointer for SAVE_REST
;;
alloc r14=ar.pfs,0,0,1,0 // must be first in insn group
mov out0=ar.ec
;;
SAVE_REST
PT_REGS_UNWIND_INFO(0)
;;
br.call.sptk.many rp=ia64_illegal_op_fault
.ret0: ;;
alloc r14=ar.pfs,0,0,3,0 // must be first in insn group
mov out0=r9
mov out1=r10
mov out2=r11
movl r15=ia64_leave_kernel
;;
mov rp=r15
mov b6=r8
;;
cmp.ne p6,p0=0,r8
(p6) br.call.dpnt.many b6=b6 // call returns to ia64_leave_kernel
br.sptk.many ia64_leave_kernel
END(dispatch_illegal_op_fault)
#ifdef CONFIG_IA32_SUPPORT
/*
* There is no particular reason for this code to be here, other than that
* there happens to be space here that would go unused otherwise. If this
* fault ever gets "unreserved", simply moved the following code to a more
* suitable spot...
*/
// IA32 interrupt entry point
ENTRY(dispatch_to_ia32_handler)
SAVE_MIN
;;
mov r14=cr.isr
ssm psr.ic | PSR_DEFAULT_BITS
;;
srlz.i // guarantee that interruption collection is on
;;
(p15) ssm psr.i
adds r3=8,r2 // Base pointer for SAVE_REST
;;
SAVE_REST
;;
mov r15=0x80
shr r14=r14,16 // Get interrupt number
;;
cmp.ne p6,p0=r14,r15
(p6) br.call.dpnt.many b6=non_ia32_syscall
adds r14=IA64_PT_REGS_R8_OFFSET + 16,sp // 16 byte hole per SW conventions
adds r15=IA64_PT_REGS_R1_OFFSET + 16,sp
;;
cmp.eq pSys,pNonSys=r0,r0 // set pSys=1, pNonSys=0
ld8 r8=[r14] // get r8
;;
st8 [r15]=r8 // save original EAX in r1 (IA32 procs don't use the GP)
;;
alloc r15=ar.pfs,0,0,6,0 // must first in an insn group
;;
ld4 r8=[r14],8 // r8 == eax (syscall number)
mov r15=IA32_NR_syscalls
;;
cmp.ltu.unc p6,p7=r8,r15
ld4 out1=[r14],8 // r9 == ecx
;;
ld4 out2=[r14],8 // r10 == edx
;;
ld4 out0=[r14] // r11 == ebx
adds r14=(IA64_PT_REGS_R13_OFFSET) + 16,sp
;;
ld4 out5=[r14],PT(R14)-PT(R13) // r13 == ebp
;;
ld4 out3=[r14],PT(R15)-PT(R14) // r14 == esi
adds r2=TI_FLAGS+IA64_TASK_SIZE,r13
;;
ld4 out4=[r14] // r15 == edi
movl r16=ia32_syscall_table
;;
(p6) shladd r16=r8,3,r16 // force ni_syscall if not valid syscall number
ld4 r2=[r2] // r2 = current_thread_info()->flags
;;
ld8 r16=[r16]
and r2=_TIF_SYSCALL_TRACEAUDIT,r2 // mask trace or audit
;;
mov b6=r16
movl r15=ia32_ret_from_syscall
cmp.eq p8,p0=r2,r0
;;
mov rp=r15
(p8) br.call.sptk.many b6=b6
br.cond.sptk ia32_trace_syscall
non_ia32_syscall:
alloc r15=ar.pfs,0,0,2,0
mov out0=r14 // interrupt #
add out1=16,sp // pointer to pt_regs
;; // avoid WAW on CFM
br.call.sptk.many rp=ia32_bad_interrupt
.ret1: movl r15=ia64_leave_kernel
;;
mov rp=r15
br.ret.sptk.many rp
END(dispatch_to_ia32_handler)
#endif /* CONFIG_IA32_SUPPORT */