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-rw-r--r--arch/xtensa/kernel/align.S128
1 files changed, 81 insertions, 47 deletions
diff --git a/arch/xtensa/kernel/align.S b/arch/xtensa/kernel/align.S
index d4cef6039a5c..890004af03a9 100644
--- a/arch/xtensa/kernel/align.S
+++ b/arch/xtensa/kernel/align.S
@@ -8,6 +8,7 @@
* this archive for more details.
*
* Copyright (C) 2001 - 2005 Tensilica, Inc.
+ * Copyright (C) 2014 Cadence Design Systems Inc.
*
* Rewritten by Chris Zankel <chris@zankel.net>
*
@@ -174,6 +175,10 @@ ENTRY(fast_unaligned)
s32i a0, a2, PT_AREG2
s32i a3, a2, PT_AREG3
+ rsr a3, excsave1
+ movi a4, fast_unaligned_fixup
+ s32i a4, a3, EXC_TABLE_FIXUP
+
/* Keep value of SAR in a0 */
rsr a0, sar
@@ -225,10 +230,6 @@ ENTRY(fast_unaligned)
addx8 a5, a6, a5
jx a5 # jump into table
- /* Invalid instruction, CRITICAL! */
-.Linvalid_instruction_load:
- j .Linvalid_instruction
-
/* Load: Load memory address. */
.Lload: movi a3, ~3
@@ -272,18 +273,6 @@ ENTRY(fast_unaligned)
/* Set target register. */
1:
-
-#if XCHAL_HAVE_LOOPS
- rsr a5, lend # check if we reached LEND
- bne a7, a5, 1f
- rsr a5, lcount # and LCOUNT != 0
- beqz a5, 1f
- addi a5, a5, -1 # decrement LCOUNT and set
- rsr a7, lbeg # set PC to LBEGIN
- wsr a5, lcount
-#endif
-
-1: wsr a7, epc1 # skip load instruction
extui a4, a4, INSN_T, 4 # extract target register
movi a5, .Lload_table
addx8 a4, a4, a5
@@ -326,6 +315,35 @@ ENTRY(fast_unaligned)
mov a3, a14 ; _j 1f; .align 8
mov a3, a15 ; _j 1f; .align 8
+ /* We cannot handle this exception. */
+
+ .extern _kernel_exception
+.Linvalid_instruction_load:
+.Linvalid_instruction_store:
+
+ movi a4, 0
+ rsr a3, excsave1
+ s32i a4, a3, EXC_TABLE_FIXUP
+
+ /* Restore a4...a8 and SAR, set SP, and jump to default exception. */
+
+ l32i a8, a2, PT_AREG8
+ l32i a7, a2, PT_AREG7
+ l32i a6, a2, PT_AREG6
+ l32i a5, a2, PT_AREG5
+ l32i a4, a2, PT_AREG4
+ wsr a0, sar
+ mov a1, a2
+
+ rsr a0, ps
+ bbsi.l a0, PS_UM_BIT, 2f # jump if user mode
+
+ movi a0, _kernel_exception
+ jx a0
+
+2: movi a0, _user_exception
+ jx a0
+
1: # a7: instruction pointer, a4: instruction, a3: value
movi a6, 0 # mask: ffffffff:00000000
@@ -353,17 +371,6 @@ ENTRY(fast_unaligned)
/* Get memory address */
1:
-#if XCHAL_HAVE_LOOPS
- rsr a4, lend # check if we reached LEND
- bne a7, a4, 1f
- rsr a4, lcount # and LCOUNT != 0
- beqz a4, 1f
- addi a4, a4, -1 # decrement LCOUNT and set
- rsr a7, lbeg # set PC to LBEGIN
- wsr a4, lcount
-#endif
-
-1: wsr a7, epc1 # skip store instruction
movi a4, ~3
and a4, a4, a8 # align memory address
@@ -375,25 +382,25 @@ ENTRY(fast_unaligned)
#endif
__ssa8r a8
- __src_b a7, a5, a6 # lo-mask F..F0..0 (BE) 0..0F..F (LE)
+ __src_b a8, a5, a6 # lo-mask F..F0..0 (BE) 0..0F..F (LE)
__src_b a6, a6, a5 # hi-mask 0..0F..F (BE) F..F0..0 (LE)
#ifdef UNALIGNED_USER_EXCEPTION
l32e a5, a4, -8
#else
l32i a5, a4, 0 # load lower address word
#endif
- and a5, a5, a7 # mask
- __sh a7, a3 # shift value
- or a5, a5, a7 # or with original value
+ and a5, a5, a8 # mask
+ __sh a8, a3 # shift value
+ or a5, a5, a8 # or with original value
#ifdef UNALIGNED_USER_EXCEPTION
s32e a5, a4, -8
- l32e a7, a4, -4
+ l32e a8, a4, -4
#else
s32i a5, a4, 0 # store
- l32i a7, a4, 4 # same for upper address word
+ l32i a8, a4, 4 # same for upper address word
#endif
__sl a5, a3
- and a6, a7, a6
+ and a6, a8, a6
or a6, a6, a5
#ifdef UNALIGNED_USER_EXCEPTION
s32e a6, a4, -4
@@ -401,9 +408,27 @@ ENTRY(fast_unaligned)
s32i a6, a4, 4
#endif
- /* Done. restore stack and return */
-
.Lexit:
+#if XCHAL_HAVE_LOOPS
+ rsr a4, lend # check if we reached LEND
+ bne a7, a4, 1f
+ rsr a4, lcount # and LCOUNT != 0
+ beqz a4, 1f
+ addi a4, a4, -1 # decrement LCOUNT and set
+ rsr a7, lbeg # set PC to LBEGIN
+ wsr a4, lcount
+#endif
+
+1: wsr a7, epc1 # skip emulated instruction
+
+ /* Update icount if we're single-stepping in userspace. */
+ rsr a4, icountlevel
+ beqz a4, 1f
+ bgeui a4, LOCKLEVEL + 1, 1f
+ rsr a4, icount
+ addi a4, a4, 1
+ wsr a4, icount
+1:
movi a4, 0
rsr a3, excsave1
s32i a4, a3, EXC_TABLE_FIXUP
@@ -424,31 +449,40 @@ ENTRY(fast_unaligned)
l32i a2, a2, PT_AREG2
rfe
- /* We cannot handle this exception. */
+ENDPROC(fast_unaligned)
- .extern _kernel_exception
-.Linvalid_instruction_store:
-.Linvalid_instruction:
+ENTRY(fast_unaligned_fixup)
- /* Restore a4...a8 and SAR, set SP, and jump to default exception. */
+ l32i a2, a3, EXC_TABLE_DOUBLE_SAVE
+ wsr a3, excsave1
l32i a8, a2, PT_AREG8
l32i a7, a2, PT_AREG7
l32i a6, a2, PT_AREG6
l32i a5, a2, PT_AREG5
l32i a4, a2, PT_AREG4
+ l32i a0, a2, PT_AREG2
+ xsr a0, depc # restore depc and a0
wsr a0, sar
- mov a1, a2
+
+ rsr a0, exccause
+ s32i a0, a2, PT_DEPC # mark as a regular exception
rsr a0, ps
- bbsi.l a2, PS_UM_BIT, 1f # jump if user mode
+ bbsi.l a0, PS_UM_BIT, 1f # jump if user mode
- movi a0, _kernel_exception
+ rsr a0, exccause
+ addx4 a0, a0, a3 # find entry in table
+ l32i a0, a0, EXC_TABLE_FAST_KERNEL # load handler
+ l32i a3, a2, PT_AREG3
jx a0
-
-1: movi a0, _user_exception
+1:
+ rsr a0, exccause
+ addx4 a0, a0, a3 # find entry in table
+ l32i a0, a0, EXC_TABLE_FAST_USER # load handler
+ l32i a3, a2, PT_AREG3
jx a0
-ENDPROC(fast_unaligned)
+ENDPROC(fast_unaligned_fixup)
#endif /* XCHAL_UNALIGNED_LOAD_EXCEPTION || XCHAL_UNALIGNED_STORE_EXCEPTION */