# HG changeset patch
# User awilliam@xxxxxxxxxxx
# Node ID fa584e5d17b65f39ef46b15952c650c0226e59cf
# Parent 7c79d49033c67e734c73423738c71671a1bb93da
[IA64] initial cleanup of ivt.S
This patch reflects a patch I recently posted to the linux-ia64
mailing list to do essentially the same thing for ivt.S in upstream
source.
I've reformatted the contents of the Xen version of ivt.S so that
they are now readable on 80-column displays, in accordance with
Linux coding standards. This is really just a first pass at
cleaning up this code.
In all of this patch, I only changed one line of assembly; there
was a 'mov r31=pr;' in entry 23 (daccess_rights) that I changed
to 'mov r31=pr;;' which is most likely what was meant. No other
instructions were changed. Hopefully, I didn't harm any other
white space formatting.
Signed-off-by: Al Stone <ahs3@xxxxxxxxx>
---
xen/arch/ia64/xen/ivt.S | 1035 ++++++++++++++++++++++++++----------------------
1 files changed, 563 insertions(+), 472 deletions(-)
diff -r 7c79d49033c6 -r fa584e5d17b6 xen/arch/ia64/xen/ivt.S
--- a/xen/arch/ia64/xen/ivt.S Mon Aug 14 13:20:40 2006 -0600
+++ b/xen/arch/ia64/xen/ivt.S Mon Aug 14 13:30:17 2006 -0600
@@ -15,7 +15,8 @@
* Fenghua Yu <fenghua.yu@xxxxxxxxx>
*
* 00/08/23 Asit Mallick <asit.k.mallick@xxxxxxxxx> TLB handling for SMP
- * 00/12/20 David Mosberger-Tang <davidm@xxxxxxxxxx> DTLB/ITLB handler now
uses virtual PT.
+ * 00/12/20 David Mosberger-Tang <davidm@xxxxxxxxxx> DTLB/ITLB handler now
+ * uses virtual PT.
*/
/*
* This file defines the interruption vector table used by the CPU.
@@ -69,10 +70,14 @@
#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...
+ * 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
+# 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
@@ -80,18 +85,18 @@
#define MINSTATE_VIRT /* needed by minstate.h */
#include "minstate.h"
-#define FAULT(n)
\
- mov r19=n; /* prepare to save predicates */
\
- mov r31=pr;
\
+#define FAULT(n) \
+ mov r19=n; /* prepare to save predicates */ \
+ mov r31=pr; \
br.sptk.many dispatch_to_fault_handler
-#define FAULT_OR_REFLECT(n)
\
- mov r20=cr.ipsr;
\
- mov r19=n; /* prepare to save predicates */
\
- mov r31=pr;;
\
- extr.u r20=r20,IA64_PSR_CPL0_BIT,2;;
\
- cmp.ne p6,p0=r0,r20; /* cpl != 0?*/
\
-(p6) br.dptk.many dispatch_reflection;
\
+#define FAULT_OR_REFLECT(n) \
+ mov r20=cr.ipsr; \
+ mov r19=n; /* prepare to save predicates */ \
+ mov r31=pr;; \
+ extr.u r20=r20,IA64_PSR_CPL0_BIT,2;; \
+ cmp.ne p6,p0=r0,r20; /* cpl != 0?*/ \
+(p6) br.dptk.many dispatch_reflection; \
br.sptk.few dispatch_to_fault_handler
.section .text.ivt,"ax"
@@ -99,7 +104,7 @@
.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)
@@ -107,33 +112,34 @@ ENTRY(vhpt_miss)
FAULT(0)
#else
/*
- * 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).
+ * 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 both L1 and L2 have valid mappings for the faulting address.
- * The TLB entry for the original miss gets inserted only if
- * the L3 entry indicates that the page is present.
+ * 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 both L1 and L2 have valid
+ * mappings for the faulting address. The TLB entry for the
+ * original miss gets inserted only if the L3 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 L1, L2, or L3 mapping
*/
- mov r16=cr.ifa // get address that caused the
TLB miss
+ 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
+ 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 r22=r21,3
#ifdef CONFIG_HUGETLB_PAGE
@@ -146,56 +152,68 @@ ENTRY(vhpt_miss)
(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 bits 33-63 of the
faulting address
- ;;
-(p7) dep r17=r17,r19,(PAGE_SHIFT-3),3 // put region number bits in
place
+ cmp.eq p6,p7=5,r17 // is IFA pointing into to region 5?
+ shr.u r18=r22,PGDIR_SHIFT // get bits 33-63 of faulting address
+ ;;
+(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
+ 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=PTA + IFA(33,42)*8
-(p7) dep r17=r18,r17,3,(PAGE_SHIFT-6) // r17=PTA + (((IFA(61,63) <<
7) | IFA(33,39))*8)
- cmp.eq p7,p6=0,r21 // unused address bits all
zeroes?
+(p7) dep r17=r18,r17,3,(PAGE_SHIFT-6) // r17=PTA +
+ // (((IFA(61,63) << 7) |
+ // IFA(33,39))*8)
+ cmp.eq p7,p6=0,r21 // unused address bits all zero?
shr.u r18=r22,PMD_SHIFT // shift L2 index into position
;;
ld8 r17=[r17] // fetch the L1 entry (may be 0)
;;
(p7) cmp.eq p6,p7=r17,r0 // was L1 entry NULL?
- dep r17=r18,r17,3,(PAGE_SHIFT-3) // compute address of L2 page
table entry
+ dep r17=r18,r17,3,(PAGE_SHIFT-3) // compute address of L2 page
+ // table entry
;;
(p7) ld8 r20=[r17] // fetch the L2 entry (may be 0)
shr.u r19=r22,PAGE_SHIFT // shift L3 index into position
;;
(p7) cmp.eq.or.andcm p6,p7=r20,r0 // was L2 entry NULL?
- dep r21=r19,r20,3,(PAGE_SHIFT-3) // compute address of L3 page
table entry
+ dep r21=r19,r20,3,(PAGE_SHIFT-3) // compute address of L3 page
+ // table entry
;;
(p7) ld8 r18=[r21] // read the L3 PTE
- mov r19=cr.isr // cr.isr bit 0 tells us if
this is an insn miss
+ mov r19=cr.isr // cr.isr bit 0 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
+ 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
+(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)
+(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.
+(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
;;
@@ -203,15 +221,15 @@ ENTRY(vhpt_miss)
;;
#ifdef CONFIG_SMP
/*
- * Tell the assemblers dependency-violation checker that the above
"itc" instructions
- * cannot possibly affect the following loads:
+ * Tell the assemblers dependency-violation checker that the above
+ * "itc" instructions cannot possibly affect the following loads:
*/
dv_serialize_data
/*
- * Re-check L2 and L3 pagetable. 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.
+ * Re-check L2 and L3 pagetable. 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.
*/
ld8 r25=[r21] // read L3 PTE again
ld8 r26=[r17] // read L2 entry again
@@ -231,7 +249,7 @@ END(vhpt_miss)
END(vhpt_miss)
.org ia64_ivt+0x400
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x0400 Entry 1 (size 64 bundles) ITLB (21)
ENTRY(itlb_miss)
DBG_FAULT(1)
@@ -266,7 +284,8 @@ ENTRY(itlb_miss)
mov r31=pr // save predicates
.itlb_fault:
mov r17=cr.iha // get virtual address of L3 PTE
- movl r30=1f // load nested fault
continuation point
+ movl r30=1f // load nested fault
+ // continuation point
;;
1: ld8 r18=[r17] // read L3 PTE
;;
@@ -278,13 +297,13 @@ 1: ld8 r18=[r17] // read
L3 PTE
;;
#ifdef CONFIG_SMP
/*
- * Tell the assemblers dependency-violation checker that the above
"itc" instructions
- * cannot possibly affect the following loads:
+ * Tell the assemblers dependency-violation checker that the above
+ * "itc" instructions cannot possibly affect the following loads:
*/
dv_serialize_data
- ld8 r19=[r17] // read L3 PTE again and see if
same
- mov r20=PAGE_SHIFT<<2 // setup page size for purge
+ ld8 r19=[r17] // read L3 PTE again and see if same
+ mov r20=PAGE_SHIFT<<2 // setup page size for purge
;;
cmp.ne p7,p0=r18,r19
;;
@@ -295,26 +314,25 @@ END(itlb_miss)
END(itlb_miss)
.org ia64_ivt+0x0800
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x0800 Entry 2 (size 64 bundles) DTLB (9,48)
ENTRY(dtlb_miss)
DBG_FAULT(2)
#ifdef XEN
- mov r16=cr.ifa // get virtual address
+ mov r16=cr.ifa // get virtual address
mov r31=pr
;;
extr.u r17=r16,59,5
;;
- /* If address belongs to VMM, go to alt tlb handler */
- cmp.eq p6,p0=0x1e,r17
+ cmp.eq p6,p0=0x1e,r17 // if the address belongs to VMM, go
+ // to the alternate tlb handler
(p6) br.cond.spnt late_alt_dtlb_miss
;;
cmp.eq p6,p0=0x1d,r17
(p6) br.cond.spnt late_alt_dtlb_miss
;;
#if VHPT_ENABLED
- // XXX TODO optimization
- mov r30=cr.ipsr
+ mov r30=cr.ipsr // XXX TODO optimization
mov r28=cr.iip
mov r17=cr.isr
;;
@@ -324,15 +342,14 @@ ENTRY(dtlb_miss)
cmp.ne p6, p0 = r0, r18 // cpl == 0?
(p6) br.cond.sptk 2f
- // is speculation bit on?
- tbit.nz p7,p0=r17,IA64_ISR_SP_BIT
+ tbit.nz p7,p0=r17,IA64_ISR_SP_BIT // is speculation bit on?
;;
(p7) br.cond.spnt 2f
- // Is the faulted iip in vmm area?
- // check [59:58] bit
- // 00, 11: guest
- // 01, 10: vmm
+ // Is the faulted iip in the vmm area?
+ // -- check [59:58] bit
+ // -- if 00, 11: guest
+ // -- if 01, 10: vmm
extr.u r19 = r28, 58, 2
;;
cmp.eq p10, p0 = 0x0, r19
@@ -341,17 +358,16 @@ ENTRY(dtlb_miss)
(p11) br.cond.sptk 2f
// Is the faulted address is in the identity mapping area?
- // 0xf000... or 0xe8000...
+ // must be either 0xf000... or 0xe8000...
extr.u r20 = r16, 59, 5
;;
- cmp.eq p12, p0 = 0x1e, r20 // (0xf0 >> 3) = 0x1e
+ cmp.eq p12, p0 = 0x1e, r20 // (0xf0 >> 3) = 0x1e
(p12) br.cond.spnt 1f
- cmp.eq p0, p13 = 0x1d, r20 // (0xe8 >> 3) = 0x1d
+ cmp.eq p0, p13 = 0x1d, r20 // (0xe8 >> 3) = 0x1d
(p13) br.cond.sptk 2f
1:
- // xen identity mappin area.
- movl r24=PAGE_KERNEL
+ movl r24=PAGE_KERNEL // xen identity mapping area.
movl r25=(((1 << IA64_MAX_PHYS_BITS) - 1) & ~0xfff)
;;
shr.u r26=r16,55 // move address bit 59 to bit 4
@@ -361,7 +377,8 @@ 1:
;;
or r25=r25,r24 // insert PTE control bits into r25
;;
- or r25=r25,r26 // set bit 4 (uncached) if the access was to
region 6
+ or r25=r25,r26 // set bit 4 (uncached) if the access was to
+ // region 6
;;
itc.d r25 // insert the TLB entry
mov pr=r31,-1
@@ -388,7 +405,8 @@ 2:
#endif
dtlb_fault:
mov r17=cr.iha // get virtual address of L3 PTE
- movl r30=1f // load nested fault
continuation point
+ movl r30=1f // load nested fault
+ // continuation point
;;
1: ld8 r18=[r17] // read L3 PTE
;;
@@ -400,13 +418,13 @@ 1: ld8 r18=[r17] // read
L3 PTE
;;
#ifdef CONFIG_SMP
/*
- * Tell the assemblers dependency-violation checker that the above
"itc" instructions
- * cannot possibly affect the following loads:
+ * Tell the assemblers dependency-violation checker that the above
+ * "itc" instructions cannot possibly affect the following loads:
*/
dv_serialize_data
- ld8 r19=[r17] // read L3 PTE again and see if
same
- mov r20=PAGE_SHIFT<<2 // setup page size for purge
+ ld8 r19=[r17] // read L3 PTE again and see if same
+ mov r20=PAGE_SHIFT<<2 // setup page size for purge
;;
cmp.ne p7,p0=r18,r19
;;
@@ -417,7 +435,7 @@ END(dtlb_miss)
END(dtlb_miss)
.org ia64_ivt+0x0c00
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x0c00 Entry 3 (size 64 bundles) Alt ITLB (19)
ENTRY(alt_itlb_miss)
DBG_FAULT(3)
@@ -439,14 +457,14 @@ late_alt_itlb_miss:
;;
#endif
#ifdef CONFIG_DISABLE_VHPT
- shr.u r22=r16,61 // get the region number into
r21
- ;;
- cmp.gt p8,p0=6,r22 // user mode
+ 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) mov r29=b0 // save b0
(p8) br.cond.dptk .itlb_fault
#endif
extr.u r23=r21,IA64_PSR_CPL0_BIT,2 // extract psr.cpl
@@ -463,7 +481,8 @@ late_alt_itlb_miss:
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
+ 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
@@ -472,7 +491,7 @@ END(alt_itlb_miss)
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)
@@ -503,13 +522,15 @@ late_alt_dtlb_miss:
tbit.nz p6,p7=r20,IA64_ISR_SP_BIT // is speculation bit on?
#ifdef XEN
shr.u r18=r16,55 // move address bit 59 to bit 4
- and r19=r19,r16 // clear ed, reserved bits, and
PTE control bits
+ and r19=r19,r16 // clear ed, reserved bits, and
+ // PTE control bits
tbit.nz p9,p0=r20,IA64_ISR_NA_BIT // is non-access bit on?
;;
and r18=0x10,r18 // bit 4=address-bit(59)
#else
shr.u r18=r16,57 // move address bit 61 to bit 4
- and r19=r19,r16 // clear ed, reserved bits, and
PTE control bits
+ and r19=r19,r16 // clear ed, reserved bits, and
+ // PTE control bits
tbit.nz p9,p0=r20,IA64_ISR_NA_BIT // is non-access bit on?
;;
andcm r18=0x10,r18 // bit 4=~address-bit(61)
@@ -520,36 +541,41 @@ late_alt_dtlb_miss:
#ifdef XEN
;;
#ifdef CONFIG_VIRTUAL_FRAME_TABLE
- // Test for the address of virtual frame_table
- shr r22=r16,56;;
+ shr r22=r16,56 // Test for the address of virtual frame_table
+ ;;
cmp.eq p8,p0=((VIRT_FRAME_TABLE_ADDR>>56)&0xff)-0x100,r22
(p8) br.cond.sptk frametable_miss ;;
#endif
- // Test for Xen address, if not handle via page_fault
- // note that 0xf000 (cached) and 0xe800 (uncached) addresses
+ // If it is not a Xen address, handle it via page_fault.
+ // Note that 0xf000 (cached) and 0xe800 (uncached) addresses
// should be OK.
- extr.u r22=r16,59,5;;
+ extr.u r22=r16,59,5
+ ;;
cmp.eq p8,p0=0x1e,r22
-(p8) br.cond.spnt 1f;;
+(p8) br.cond.spnt 1f
+ ;;
cmp.ne p8,p0=0x1d,r22
-(p8) br.cond.sptk page_fault ;;
+(p8) br.cond.sptk page_fault
+ ;;
1:
#endif
dep r21=-1,r21,IA64_PSR_ED_BIT,1
or r19=r19,r17 // insert PTE control bits into r19
;;
- or r19=r19,r18 // set bit 4 (uncached) if the access was to
region 6
+ or r19=r19,r18 // set bit 4 (uncached) if the access was to
+ // region 6
(p6) mov cr.ipsr=r21
;;
(p7) itc.d r19 // insert the TLB entry
mov pr=r31,-1
rfi
END(alt_dtlb_miss)
+
#ifdef CONFIG_VIRTUAL_FRAME_TABLE
GLOBAL_ENTRY(frametable_miss)
rsm psr.dt // switch to using physical data addressing
- movl r24=(frametable_pg_dir-PAGE_OFFSET) //
r24=__pa(frametable_pg_dir)
+ movl r24=(frametable_pg_dir-PAGE_OFFSET) // r24=__pa(frametable_pg_dir)
;;
srlz.d
extr.u r17=r16,PGDIR_SHIFT,(PAGE_SHIFT-3)
@@ -583,6 +609,7 @@ GLOBAL_ENTRY(frametable_miss)
mov pr=r31,-1 // restore predicate registers
rfi
END(frametable_miss)
+
ENTRY(frametable_fault)
ssm psr.dt // switch to using virtual data addressing
mov r18=cr.iip
@@ -590,7 +617,8 @@ ENTRY(frametable_fault)
;;
cmp.eq p6,p7=r18,r19 // is faulting addrress ia64_frametable_probe?
mov r8=0 // assumes that 'probe.r' uses r8
- dep r21=-1,r21,IA64_PSR_RI_BIT+1,1 // return to next instrucition in
bundle 2
+ dep r21=-1,r21,IA64_PSR_RI_BIT+1,1 // return to next instruction in
+ // bundle 2
;;
(p6) mov cr.ipsr=r21
mov r19=4 // FAULT(4)
@@ -599,6 +627,7 @@ ENTRY(frametable_fault)
mov pr=r31,-1
rfi
END(frametable_fault)
+
GLOBAL_ENTRY(ia64_frametable_probe)
{
probe.r r8=r32,0 // destination register must be r8
@@ -615,18 +644,19 @@ ENTRY(nested_dtlb_miss)
DBG_FAULT(5)
#ifdef XEN
mov b0=r30
- br.sptk.many b0 // return to continuation point
- ;;
-#else
- /*
- * 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).
+ br.sptk.many b0 // return to the continuation point
+ ;;
+#else
+ /*
+ * 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
@@ -640,47 +670,52 @@ ENTRY(nested_dtlb_miss)
*
* Clobbered: b0, r18, r19, r21, 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
- ;;
- shr.u r17=r16,61 // get the region number into
r17
- ;;
- cmp.eq p6,p7=5,r17 // is faulting address in
region 5?
- shr.u r18=r16,PGDIR_SHIFT // get bits 33-63 of faulting
address
- ;;
-(p7) dep r17=r17,r19,(PAGE_SHIFT-3),3 // put region number bits in
place
+ 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
+ ;;
+ shr.u r17=r16,61 // get the region number into r17
+ ;;
+ cmp.eq p6,p7=5,r17 // is faulting address in region 5?
+ shr.u r18=r16,PGDIR_SHIFT // get bits 33-63 of faulting address
+ ;;
+(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
+ 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=PTA + IFA(33,42)*8
-(p7) dep r17=r18,r17,3,(PAGE_SHIFT-6) // r17=PTA + (((IFA(61,63) <<
7) | IFA(33,39))*8)
- cmp.eq p7,p6=0,r21 // unused address bits all
zeroes?
- shr.u r18=r16,PMD_SHIFT // shift L2 index into position
- ;;
- ld8 r17=[r17] // fetch the L1 entry (may be 0)
- ;;
-(p7) cmp.eq p6,p7=r17,r0 // was L1 entry NULL?
- dep r17=r18,r17,3,(PAGE_SHIFT-3) // compute address of L2 page
table entry
- ;;
-(p7) ld8 r17=[r17] // fetch the L2 entry (may be 0)
- shr.u r19=r16,PAGE_SHIFT // shift L3 index into position
- ;;
-(p7) cmp.eq.or.andcm p6,p7=r17,r0 // was L2 entry NULL?
- dep r17=r19,r17,3,(PAGE_SHIFT-3) // compute address of L3 page
table entry
+(p6) dep r17=r18,r19,3,(PAGE_SHIFT-3) // r17=PTA + IFA(33,42)*8
+(p7) dep r17=r18,r17,3,(PAGE_SHIFT-6) // r17=PTA + (((IFA(61,63) << 7) |
+ // IFA(33,39))*8)
+ cmp.eq p7,p6=0,r21 // unused address bits all zeroes?
+ shr.u r18=r16,PMD_SHIFT // shift L2 index into position
+ ;;
+ ld8 r17=[r17] // fetch the L1 entry (may be 0)
+ ;;
+(p7) cmp.eq p6,p7=r17,r0 // was L1 entry NULL?
+ dep r17=r18,r17,3,(PAGE_SHIFT-3) // compute address of L2 page table
+ // entry
+ ;;
+(p7) ld8 r17=[r17] // fetch the L2 entry (may be 0)
+ shr.u r19=r16,PAGE_SHIFT // shift L3 index into position
+ ;;
+(p7) cmp.eq.or.andcm p6,p7=r17,r0 // was L2 entry NULL?
+ dep r17=r19,r17,3,(PAGE_SHIFT-3) // compute address of L3 page table
+ // entry
(p6) br.cond.spnt page_fault
mov b0=r30
- br.sptk.many b0 // return to continuation point
+ br.sptk.many b0 // return to continuation point
#endif
END(nested_dtlb_miss)
.org ia64_ivt+0x1800
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x1800 Entry 6 (size 64 bundles) Instruction Key Miss (24)
ENTRY(ikey_miss)
DBG_FAULT(6)
@@ -691,8 +726,9 @@ ENTRY(ikey_miss)
#endif
END(ikey_miss)
-
//-----------------------------------------------------------------------------------
- // call do_page_fault (predicates are in r31, psr.dt may be off, r16 is
faulting address)
+ //----------------------------------------------------------------
+ // call do_page_fault (predicates are in r31, psr.dt may be off,
+ // r16 is faulting address)
#ifdef XEN
GLOBAL_ENTRY(page_fault)
#else
@@ -713,24 +749,25 @@ ENTRY(page_fault)
mov out0=cr.ifa
mov out1=cr.isr
#endif
- adds r3=8,r2 // set up second base pointer
+ 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
+ srlz.i // guarantee that interruption
+ // collection 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
+ 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)
@@ -742,32 +779,33 @@ END(dkey_miss)
END(dkey_miss)
.org ia64_ivt+0x2000
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x2000 Entry 8 (size 64 bundles) Dirty-bit (54)
ENTRY(dirty_bit)
DBG_FAULT(8)
#ifdef XEN
mov r20=cr.ipsr
- mov r31=pr;;
- extr.u r20=r20,IA64_PSR_CPL0_BIT,2;;
- mov r19=8 /* prepare to save predicates */
- cmp.eq p6,p0=r0,r20 /* cpl == 0?*/
+ mov r31=pr
+ ;;
+ extr.u r20=r20,IA64_PSR_CPL0_BIT,2
+ ;;
+ mov r19=8 // prepare to save predicates
+ cmp.eq p6,p0=r0,r20 // cpl == 0?
(p6) br.sptk.few dispatch_to_fault_handler
- /* If shadow mode is not enabled, reflect the fault. */
+ // If shadow mode is not enabled, reflect the fault.
movl r22=THIS_CPU(cpu_kr)+IA64_KR_CURRENT_OFFSET
;;
ld8 r22=[r22]
;;
add r22=IA64_VCPU_DOMAIN_OFFSET,r22
;;
- /* Read domain. */
+ ld8 r22=[r22] // read domain
+ ;;
+ add r22=IA64_DOMAIN_SHADOW_BITMAP_OFFSET,r22
+ ;;
ld8 r22=[r22]
;;
- add r22=IA64_DOMAIN_SHADOW_BITMAP_OFFSET,r22
- ;;
- ld8 r22=[r22]
- ;;
- cmp.eq p6,p0=r0,r22 /* !shadow_bitmap ?*/
+ cmp.eq p6,p0=r0,r22 // !shadow_bitmap ?
(p6) br.dptk.many dispatch_reflection
SAVE_MIN_WITH_COVER
@@ -779,10 +817,11 @@ ENTRY(dirty_bit)
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
+ 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
@@ -791,65 +830,69 @@ ENTRY(dirty_bit)
br.call.sptk.many b6=ia64_shadow_fault
#else
/*
- * 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
+ * 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
+ 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
+ ;; // 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
;;
cmpxchg8.acq r26=[r17],r25,ar.ccv
mov r24=PAGE_SHIFT<<2
;;
cmp.eq p6,p7=r26,r18
;;
-(p6) itc.d r25 // install updated PTE
- ;;
- /*
- * Tell the assemblers dependency-violation checker that the above
"itc" instructions
- * cannot possibly affect the following loads:
+(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
+ 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 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
+ ;; // 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
#endif
END(dirty_bit)
.org ia64_ivt+0x2400
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x2400 Entry 9 (size 64 bundles) Instruction Access-bit (27)
ENTRY(iaccess_bit)
DBG_FAULT(9)
@@ -862,9 +905,11 @@ ENTRY(iaccess_bit)
br.sptk.many fast_access_reflect;;
#else
// 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
+ 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.
@@ -872,50 +917,50 @@ ENTRY(iaccess_bit)
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
+ 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)
+ 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
+ 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
+ mov ar.ccv=r18 // set compare value for cmpxchg
+ or r25=_PAGE_A,r18 // set the accessed bit
;;
cmpxchg8.acq r26=[r17],r25,ar.ccv
mov r24=PAGE_SHIFT<<2
;;
cmp.eq p6,p7=r26,r18
;;
-(p6) itc.i r25 // install updated PTE
- ;;
- /*
- * Tell the assemblers dependency-violation checker that the above
"itc" instructions
- * cannot possibly affect the following loads:
+(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
+ 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 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
+ 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
@@ -923,7 +968,7 @@ END(iaccess_bit)
END(iaccess_bit)
.org ia64_ivt+0x2800
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x2800 Entry 10 (size 64 bundles) Data Access-bit (15,55)
ENTRY(daccess_bit)
DBG_FAULT(10)
@@ -933,74 +978,80 @@ ENTRY(daccess_bit)
mov r31=pr
mov r19=10
mov r20=0x2800
- br.sptk.many fast_access_reflect;;
+ br.sptk.many fast_access_reflect
+ ;;
#else
// 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 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)
+ mov r29=b0 // save b0 in case of nested fault)
#ifdef CONFIG_SMP
- mov r28=ar.ccv // save ar.ccv
+ 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
+ ;; // avoid RAW on r18
+ mov ar.ccv=r18 // set compare value for cmpxchg
+ or r25=_PAGE_A,r18 // set the dirty bit
;;
cmpxchg8.acq r26=[r17],r25,ar.ccv
mov r24=PAGE_SHIFT<<2
;;
cmp.eq p6,p7=r26,r18
;;
-(p6) itc.d r25 // install updated PTE
- /*
- * Tell the assemblers dependency-violation checker that the above
"itc" instructions
- * cannot possibly affect the following loads:
+(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
+ 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
+ ;; // 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
#endif
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.
+ * 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
+ * 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.
+ * During system call exit, scratch registers (including r15) are
+ * modified/cleared to prevent leaking bits from kernel to user
+ * level.
*/
DBG_FAULT(11)
#ifdef XEN
@@ -1009,13 +1060,17 @@ ENTRY(break_fault)
mov r31=pr
;;
cmp.eq p7,p0=r17,r0
-(p7) br.spnt.few dispatch_break_fault ;;
+(p7) br.spnt.few dispatch_break_fault
+ ;;
#ifdef CRASH_DEBUG
- // panic can occur before domain0 is created.
- // in such case referencing XSI_PSR_IC causes nested_dtlb_miss
- movl r18=CDB_BREAK_NUM ;;
- cmp.eq p7,p0=r17,r18 ;;
-(p7) br.spnt.few dispatch_break_fault ;;
+ // A panic can occur before domain0 is created. In such cases,
+ // referencing XSI_PSR_IC causes nested_dtlb_miss.
+ movl r18=CDB_BREAK_NUM
+ ;;
+ cmp.eq p7,p0=r17,r18
+ ;;
+(p7) br.spnt.few dispatch_break_fault
+ ;;
#endif
movl r18=THIS_CPU(current_psr_ic_addr)
;;
@@ -1026,17 +1081,19 @@ ENTRY(break_fault)
cmp.eq p7,p0=r0,r17 // is this a psuedo-cover?
(p7) br.spnt.many dispatch_privop_fault
;;
- // if vpsr.ic is off, we have a hyperprivop
- // A hyperprivop is hand-coded assembly with psr.ic off
- // which means no calls, no use of r1-r15 and no memory accesses
- // except to pinned addresses!
+ // If vpsr.ic is off, we have a hyperprivop. A hyperprivop is
+ // hand-coded assembly with psr.ic off which means it can make
+ // no calls, cannot use r1-r15, and it can have no memory accesses
+ // unless they are to pinned addresses!
cmp4.eq p7,p0=r0,r19
(p7) br.sptk.many fast_hyperprivop
;;
- movl r22=THIS_CPU(cpu_kr)+IA64_KR_CURRENT_OFFSET;;
+ movl r22=THIS_CPU(cpu_kr)+IA64_KR_CURRENT_OFFSET
+ ;;
ld8 r22 = [r22]
;;
- adds r22=IA64_VCPU_BREAKIMM_OFFSET,r22;;
+ adds r22=IA64_VCPU_BREAKIMM_OFFSET,r22
+ ;;
ld4 r23=[r22];;
cmp4.eq p6,p7=r23,r17 // Xen-reserved breakimm?
(p6) br.spnt.many dispatch_break_fault
@@ -1056,78 +1113,86 @@ ENTRY(break_fault)
mov r26=ar.pfs
mov r28=cr.iip
#ifndef XEN
- mov r31=pr // prepare to save predicates
+ mov r31=pr // prepare to save predicates
#endif
mov r20=r1
;;
adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16
- cmp.eq p0,p7=r18,r17 // is this a system call? (p7
<- false, if so)
+ cmp.eq p0,p7=r18,r17 // is this a system call?
+ // (p7 <- false, if so)
(p7) br.cond.spnt non_syscall
;;
- ld1 r17=[r16] // load
current->thread.on_ustack flag
- st1 [r16]=r0 // clear
current->thread.on_ustack flag
- add r1=-IA64_TASK_THREAD_ON_USTACK_OFFSET,r16 // set r1 for
MINSTATE_START_SAVE_MIN_VIRT
+ ld1 r17=[r16] // load current->thread.on_ustack flag
+ st1 [r16]=r0 // clear current->thread.on_ustack flag
+ add r1=-IA64_TASK_THREAD_ON_USTACK_OFFSET,r16
+ // set r1 for
+ // MINSTATE_START_SAVE_MIN_VIRT
;;
invala
/* adjust return address so we skip over the break instruction: */
- extr.u r8=r29,41,2 // extract ei field from cr.ipsr
- ;;
- cmp.eq p6,p7=2,r8 // isr.ei==2?
- mov r2=r1 // setup r2 for
ia64_syscall_setup
- ;;
-(p6) mov r8=0 // clear ei to 0
-(p6) adds r28=16,r28 // switch cr.iip to next bundle
cr.ipsr.ei wrapped
-(p7) adds r8=1,r8 // increment ei to next slot
- ;;
- cmp.eq pKStk,pUStk=r0,r17 // are we in kernel mode
already?
- dep r29=r8,r29,41,2 // insert new ei into cr.ipsr
+ extr.u r8=r29,41,2 // extract ei field from cr.ipsr
+ ;;
+ cmp.eq p6,p7=2,r8 // isr.ei==2?
+ mov r2=r1 // setup r2 for ia64_syscall_setup
+ ;;
+(p6) mov r8=0 // clear ei to 0
+(p6) adds r28=16,r28 // switch cr.iip to next bundle
+ // cr.ipsr.ei wrapped
+(p7) adds r8=1,r8 // increment ei to next slot
+ ;;
+ cmp.eq pKStk,pUStk=r0,r17 // are we in kernel mode already?
+ dep r29=r8,r29,41,2 // insert new ei into cr.ipsr
;;
// switch from user to kernel RBS:
MINSTATE_START_SAVE_MIN_VIRT
br.call.sptk.many b7=ia64_syscall_setup
;;
- MINSTATE_END_SAVE_MIN_VIRT // switch to bank 1
+ MINSTATE_END_SAVE_MIN_VIRT // switch to bank 1
ssm psr.ic | PSR_DEFAULT_BITS
;;
- srlz.i // guarantee that interruption
collection is on
+ srlz.i // guarantee that interruption
+ // collection is on
mov r3=NR_syscalls - 1
;;
-(p15) ssm psr.i // restore psr.i
+(p15) ssm psr.i // restore psr.i
// p10==true means out registers are more than 8 or r15's Nat is true
(p10) br.cond.spnt.many ia64_ret_from_syscall
;;
movl r16=sys_call_table
- adds r15=-1024,r15 // r15 contains the syscall
number---subtract 1024
+ adds r15=-1024,r15 // r15 contains the syscall number --
+ // subtract 1024 from it
movl r2=ia64_ret_from_syscall
;;
- shladd r20=r15,3,r16 // r20 = sys_call_table +
8*(syscall-1024)
- cmp.leu p6,p7=r15,r3 // (syscall > 0 && syscall <
1024 + NR_syscalls) ?
- mov rp=r2 // set the real return addr
- ;;
-(p6) ld8 r20=[r20] // load address of syscall
entry point
+ shladd r20=r15,3,r16 // r20 = sys_call_table +
+ // 8*(syscall-1024)
+ cmp.leu p6,p7=r15,r3 // (syscall > 0 && syscall < 1024 +
+ // NR_syscalls) ?
+ mov rp=r2 // set the real return addr
+ ;;
+(p6) ld8 r20=[r20] // load address of syscall entry point
(p7) movl r20=sys_ni_syscall
add r2=TI_FLAGS+IA64_TASK_SIZE,r13
;;
- ld4 r2=[r2] // r2 =
current_thread_info()->flags
- ;;
- and r2=_TIF_SYSCALL_TRACEAUDIT,r2 // mask trace or audit
+ ld4 r2=[r2] // r2 = current_thread_info()->flags
+ ;;
+ and r2=_TIF_SYSCALL_TRACEAUDIT,r2 // mask trace or audit
;;
cmp.eq p8,p0=r2,r0
mov b6=r20
;;
-(p8) br.call.sptk.many b6=b6 // ignore this return addr
+(p8) br.call.sptk.many b6=b6 // ignore this return addr
br.cond.sptk ia64_trace_syscall
// NOT REACHED
#endif
END(break_fault)
.org ia64_ivt+0x3000
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x3000 Entry 12 (size 64 bundles) External Interrupt (4)
ENTRY(interrupt)
DBG_FAULT(12)
@@ -1138,11 +1203,16 @@ ENTRY(interrupt)
// FIXME: this is a hack... use cpuinfo.ksoftirqd because its
// not used anywhere else and we need a place to stash ivr and
// there's no registers available unused by SAVE_MIN/REST
- movl r29=THIS_CPU(cpu_info)+IA64_CPUINFO_KSOFTIRQD_OFFSET;;
- st8 [r29]=r30;;
- movl r28=slow_interrupt;;
- mov r29=rp;;
- mov rp=r28;;
+ movl r29=THIS_CPU(cpu_info)+IA64_CPUINFO_KSOFTIRQD_OFFSET
+ ;;
+ st8 [r29]=r30
+ ;;
+ movl r28=slow_interrupt
+ ;;
+ mov r29=rp
+ ;;
+ mov rp=r28
+ ;;
br.cond.sptk.many fast_tick_reflect
;;
slow_interrupt:
@@ -1175,16 +1245,16 @@ END(interrupt)
END(interrupt)
.org ia64_ivt+0x3400
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x3400 Entry 13 (size 64 bundles) Reserved
DBG_FAULT(13)
FAULT(13)
#ifdef XEN
- // 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...
+ // 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 move
+ // the following code to a more suitable spot...
GLOBAL_ENTRY(dispatch_break_fault)
SAVE_MIN_WITH_COVER
@@ -1198,32 +1268,32 @@ dispatch_break_fault_post_save:
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
+ 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_break
- br.call.sptk.many b6=ia64_handle_break
+// br.sptk.many ia64_prepare_handle_break // TODO: why commented out?
+ br.call.sptk.many b6=ia64_handle_break
END(dispatch_break_fault)
#endif
.org ia64_ivt+0x3800
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x3800 Entry 14 (size 64 bundles) Reserved
DBG_FAULT(14)
FAULT(14)
#ifndef XEN
/*
- * 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...
+ * 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 move
+ * 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
@@ -1271,11 +1341,11 @@ GLOBAL_ENTRY(ia64_syscall_setup)
# error This code assumes that b6 is the first field in pt_regs.
#endif
#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 [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
@@ -1312,18 +1382,20 @@ GLOBAL_ENTRY(ia64_syscall_setup)
tnat.nz p11,p0=in3
;;
(p10) mov in2=-1
- tnat.nz p12,p0=in4 // [I0]
+ 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"
+ 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"
+ 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
;;
@@ -1336,32 +1408,34 @@ GLOBAL_ENTRY(ia64_syscall_setup)
tnat.nz p14,p0=in6
cmp.lt p10,p9=r11,r8 // frame size can't be more than local+8
;;
- stf8 [r16]=f1 // ensure pt_regs.r8 != 0 (see
handle_syscall_error)
+ stf8 [r16]=f1 // ensure pt_regs.r8 != 0
+ // (see handle_syscall_error)
(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
+ 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
+ mov r13=r2 // establish `current'
+ movl r1=__gp // establish kernel global pointer
;;
(p14) mov in6=-1
(p8) mov in7=-1
nop.i 0
- cmp.eq pSys,pNonSys=r0,r0 // set pSys=1, pNonSys=0
+ 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
+ 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)
#endif /* XEN */
.org ia64_ivt+0x3c00
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x3c00 Entry 15 (size 64 bundles) Reserved
DBG_FAULT(15)
FAULT(15)
@@ -1370,11 +1444,12 @@ END(ia64_syscall_setup)
/*
* 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.
+ * 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)
SAVE_MIN_WITH_COVER
@@ -1408,21 +1483,22 @@ END(dispatch_illegal_op_fault)
#endif
.org ia64_ivt+0x4000
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x4000 Entry 16 (size 64 bundles) Reserved
DBG_FAULT(16)
FAULT(16)
#ifdef XEN
- // 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...
+ // 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 move
+ // the following code to a more suitable spot...
ENTRY(dispatch_privop_fault)
SAVE_MIN_WITH_COVER
;;
- alloc r14=ar.pfs,0,0,4,0 // now it's safe (must be first
in insn group!)
+ alloc r14=ar.pfs,0,0,4,0 // now it's safe (must be first in
+ // insn group!)
mov out0=cr.ifa
adds out1=16,sp
mov out2=cr.isr // FIXME: pity to make this slow access twice
@@ -1430,23 +1506,24 @@ ENTRY(dispatch_privop_fault)
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
+ 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_privop
- br.call.sptk.many b6=ia64_handle_privop
+// br.sptk.many ia64_prepare_handle_privop // TODO: why commented out?
+ br.call.sptk.many b6=ia64_handle_privop
END(dispatch_privop_fault)
#endif
.org ia64_ivt+0x4400
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x4400 Entry 17 (size 64 bundles) Reserved
DBG_FAULT(17)
FAULT(17)
@@ -1455,77 +1532,80 @@ ENTRY(non_syscall)
ENTRY(non_syscall)
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...
+ // 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 move
+ // 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
+ 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
+ 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
+ br.call.sptk.many b6=ia64_bad_break // avoid WAW on CFM and
+ // ignore return addr
END(non_syscall)
#endif
.org ia64_ivt+0x4800
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x4800 Entry 18 (size 64 bundles) Reserved
DBG_FAULT(18)
FAULT(18)
#ifndef XEN
/*
- * 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...
+ * 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 move
+ * 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!)
+ 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
+ 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
- br.call.sptk.many b6=ia64_handle_unaligned
+// br.sptk.many ia64_prepare_handle_unaligned // TODO: why commented out?
+ br.call.sptk.many b6=ia64_handle_unaligned
END(dispatch_unaligned_handler)
#endif
.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...
+ * 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 move
+ * the following code to a more suitable spot...
*/
GLOBAL_ENTRY(dispatch_to_fault_handler)
@@ -1545,10 +1625,12 @@ GLOBAL_ENTRY(dispatch_to_fault_handler)
;;
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
+ 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
@@ -1562,7 +1644,7 @@ END(dispatch_to_fault_handler)
//
.org ia64_ivt+0x5000
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x5000 Entry 20 (size 16 bundles) Page Not Present (10,22,49)
ENTRY(page_not_present)
DBG_FAULT(20)
@@ -1572,8 +1654,9 @@ ENTRY(page_not_present)
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.
+ * 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
;;
@@ -1586,7 +1669,7 @@ END(page_not_present)
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)
@@ -1603,7 +1686,7 @@ END(key_permission)
END(key_permission)
.org ia64_ivt+0x5200
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x5200 Entry 22 (size 16 bundles) Instruction Access Rights (26)
ENTRY(iaccess_rights)
DBG_FAULT(22)
@@ -1620,17 +1703,19 @@ END(iaccess_rights)
END(iaccess_rights)
.org ia64_ivt+0x5300
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x5300 Entry 23 (size 16 bundles) Data Access Rights (14,53)
ENTRY(daccess_rights)
DBG_FAULT(23)
#ifdef XEN
- mov r31=pr;
+ mov r31=pr
+ ;;
mov r16=cr.isr
mov r17=cr.ifa
mov r19=23
movl r20=0x5300
- br.sptk.many fast_access_reflect;;
+ br.sptk.many fast_access_reflect
+ ;;
#else
mov r16=cr.ifa
rsm psr.dt
@@ -1642,7 +1727,7 @@ END(daccess_rights)
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)
@@ -1662,12 +1747,12 @@ END(general_exception)
END(general_exception)
.org ia64_ivt+0x5500
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x5500 Entry 25 (size 16 bundles) Disabled FP-Register (35)
ENTRY(disabled_fp_reg)
DBG_FAULT(25)
#ifdef XEN
-#if 0
+#if 0 // TODO: can this be removed?
mov r20=pr
movl r16=0x2000000000000000
movl r17=0x2000000000176b60
@@ -1686,7 +1771,7 @@ ENTRY(disabled_fp_reg)
;;
#endif
FAULT_OR_REFLECT(25)
-//floating_panic:
+//floating_panic: // TODO: can this be removed?
// br.sptk.many floating_panic
;;
#endif
@@ -1699,7 +1784,7 @@ END(disabled_fp_reg)
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)
@@ -1711,7 +1796,7 @@ END(nat_consumption)
END(nat_consumption)
.org ia64_ivt+0x5700
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x5700 Entry 27 (size 16 bundles) Speculation (40)
ENTRY(speculation_vector)
DBG_FAULT(27)
@@ -1720,12 +1805,13 @@ ENTRY(speculation_vector)
FAULT_OR_REFLECT(27)
#else
/*
- * 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.
+ * 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)
*/
@@ -1753,13 +1839,13 @@ END(speculation_vector)
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)
@@ -1771,7 +1857,7 @@ END(debug_vector)
END(debug_vector)
.org ia64_ivt+0x5a00
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x5a00 Entry 30 (size 16 bundles) Unaligned Reference (57)
ENTRY(unaligned_access)
DBG_FAULT(30)
@@ -1786,7 +1872,7 @@ END(unaligned_access)
END(unaligned_access)
.org ia64_ivt+0x5b00
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x5b00 Entry 31 (size 16 bundles) Unsupported Data Reference (57)
ENTRY(unsupported_data_reference)
DBG_FAULT(31)
@@ -1798,7 +1884,7 @@ END(unsupported_data_reference)
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)
@@ -1810,7 +1896,7 @@ END(floating_point_fault)
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)
@@ -1822,7 +1908,7 @@ END(floating_point_trap)
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)
@@ -1834,7 +1920,7 @@ END(lower_privilege_trap)
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)
@@ -1846,7 +1932,7 @@ END(taken_branch_trap)
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)
@@ -1858,56 +1944,58 @@ END(single_step_trap)
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)
+//////////////////////////////////////////////////////////////////////////
+// 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)
#ifdef XEN
@@ -1918,7 +2006,7 @@ END(ia32_exception)
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)
@@ -1952,7 +2040,7 @@ END(ia32_intercept)
END(ia32_intercept)
.org ia64_ivt+0x6b00
-/////////////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
// 0x6b00 Entry 47 (size 16 bundles) IA-32 Interrupt (74)
ENTRY(ia32_interrupt)
DBG_FAULT(47)
@@ -1969,121 +2057,121 @@ END(ia32_interrupt)
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)
@@ -2104,21 +2192,22 @@ GLOBAL_ENTRY(dispatch_reflection)
adds out1=16,sp
mov out2=cr.isr
mov out3=cr.iim
-// mov out3=cr.itir
+// mov out3=cr.itir // TODO: why commented out?
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
+ 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_reflection
- br.call.sptk.many b6=ia64_handle_reflection
+// br.sptk.many ia64_prepare_handle_reflection // TODO: why commented out?
+ br.call.sptk.many b6=ia64_handle_reflection
END(dispatch_reflection)
#define SAVE_MIN_COVER_DONE DO_SAVE_MIN(,mov r30=cr.ifs,)
@@ -2134,10 +2223,10 @@ END(dispatch_slow_hyperprivop)
#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...
+ * 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 move
+ * the following code to a more suitable spot...
*/
// IA32 interrupt entry point
@@ -2148,7 +2237,7 @@ ENTRY(dispatch_to_ia32_handler)
mov r14=cr.isr
ssm psr.ic | PSR_DEFAULT_BITS
;;
- srlz.i // guarantee that interruption
collection is on
+ srlz.i // guarantee that interruption collection is on
;;
(p15) ssm psr.i
adds r3=8,r2 // Base pointer for SAVE_REST
@@ -2161,15 +2250,17 @@ ENTRY(dispatch_to_ia32_handler)
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 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
+ st8 [r15]=r8 // save original EAX in r1 (IA32 procs
+ // don't use the GP)
+ ;;
+ alloc r15=ar.pfs,0,0,6,0 // must be first in an insn group
;;
ld4 r8=[r14],8 // r8 == eax (syscall number)
mov r15=IA32_NR_syscalls
@@ -2208,7 +2299,7 @@ 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
+ ;; // avoid WAW on CFM
br.call.sptk.many rp=ia32_bad_interrupt
.ret1: movl r15=ia64_leave_kernel
;;
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