diff options
Diffstat (limited to 'arch/xtensa/kernel/align.S')
| -rw-r--r-- | arch/xtensa/kernel/align.S | 128 |
1 files changed, 81 insertions, 47 deletions
diff --git a/arch/xtensa/kernel/align.S b/arch/xtensa/kernel/align.S index d4cef6039a5..890004af03a 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 */ |