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-rw-r--r--arch/openrisc/kernel/entry.S60
1 files changed, 38 insertions, 22 deletions
diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index aac0bde3330c..bc6500860f4d 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -173,6 +173,11 @@ handler: ;\
l.j _ret_from_exception ;\
l.nop
+/* clobbers 'reg' */
+#define CLEAR_LWA_FLAG(reg) \
+ l.movhi reg,hi(lwa_flag) ;\
+ l.ori reg,reg,lo(lwa_flag) ;\
+ l.sw 0(reg),r0
/*
* NOTE: one should never assume that SPR_EPC, SPR_ESR, SPR_EEAR
* contain the same values as when exception we're handling
@@ -193,6 +198,7 @@ EXCEPTION_ENTRY(_tng_kernel_start)
/* ---[ 0x200: BUS exception ]------------------------------------------- */
EXCEPTION_ENTRY(_bus_fault_handler)
+ CLEAR_LWA_FLAG(r3)
/* r4: EA of fault (set by EXCEPTION_HANDLE) */
l.jal do_bus_fault
l.addi r3,r1,0 /* pt_regs */
@@ -202,11 +208,13 @@ EXCEPTION_ENTRY(_bus_fault_handler)
/* ---[ 0x300: Data Page Fault exception ]------------------------------- */
EXCEPTION_ENTRY(_dtlb_miss_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
l.and r5,r5,r0
l.j 1f
l.nop
EXCEPTION_ENTRY(_data_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
/* set up parameters for do_page_fault */
l.ori r5,r0,0x300 // exception vector
1:
@@ -220,7 +228,7 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
* DTLB miss handler in the CONFIG_GUARD_PROTECTED_CORE part
*/
#ifdef CONFIG_OPENRISC_NO_SPR_SR_DSX
- l.lwz r6,PT_PC(r3) // address of an offending insn
+ l.lwz r6,PT_PC(r3) // address of an offending insn
l.lwz r6,0(r6) // instruction that caused pf
l.srli r6,r6,26 // check opcode for jump insn
@@ -236,57 +244,57 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
l.bf 8f
l.sfeqi r6,0x12 // l.jalr
l.bf 8f
-
- l.nop
+ l.nop
l.j 9f
- l.nop
-8:
+ l.nop
- l.lwz r6,PT_PC(r3) // address of an offending insn
+8: // offending insn is in delay slot
+ l.lwz r6,PT_PC(r3) // address of an offending insn
l.addi r6,r6,4
l.lwz r6,0(r6) // instruction that caused pf
l.srli r6,r6,26 // get opcode
-9:
+9: // offending instruction opcode loaded in r6
#else
- l.mfspr r6,r0,SPR_SR // SR
-// l.lwz r6,PT_SR(r3) // ESR
- l.andi r6,r6,SPR_SR_DSX // check for delay slot exception
- l.sfeqi r6,0x1 // exception happened in delay slot
- l.bnf 7f
- l.lwz r6,PT_PC(r3) // address of an offending insn
+ l.lwz r6,PT_SR(r3) // SR
+ l.andi r6,r6,SPR_SR_DSX // check for delay slot exception
+ l.sfne r6,r0 // exception happened in delay slot
+ l.bnf 7f
+ l.lwz r6,PT_PC(r3) // address of an offending insn
- l.addi r6,r6,4 // offending insn is in delay slot
+ l.addi r6,r6,4 // offending insn is in delay slot
7:
l.lwz r6,0(r6) // instruction that caused pf
l.srli r6,r6,26 // check opcode for write access
#endif
- l.sfgeui r6,0x33 // check opcode for write access
+ l.sfgeui r6,0x33 // check opcode for write access
l.bnf 1f
l.sfleui r6,0x37
l.bnf 1f
l.ori r6,r0,0x1 // write access
l.j 2f
- l.nop
+ l.nop
1: l.ori r6,r0,0x0 // !write access
2:
/* call fault.c handler in or32/mm/fault.c */
l.jal do_page_fault
- l.nop
+ l.nop
l.j _ret_from_exception
- l.nop
+ l.nop
/* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
EXCEPTION_ENTRY(_itlb_miss_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
l.and r5,r5,r0
l.j 1f
l.nop
EXCEPTION_ENTRY(_insn_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
/* set up parameters for do_page_fault */
l.ori r5,r0,0x400 // exception vector
1:
@@ -296,14 +304,15 @@ EXCEPTION_ENTRY(_insn_page_fault_handler)
/* call fault.c handler in or32/mm/fault.c */
l.jal do_page_fault
- l.nop
+ l.nop
l.j _ret_from_exception
- l.nop
+ l.nop
/* ---[ 0x500: Timer exception ]----------------------------------------- */
EXCEPTION_ENTRY(_timer_handler)
+ CLEAR_LWA_FLAG(r3)
l.jal timer_interrupt
l.addi r3,r1,0 /* pt_regs */
@@ -313,6 +322,7 @@ EXCEPTION_ENTRY(_timer_handler)
/* ---[ 0x600: Aligment exception ]-------------------------------------- */
EXCEPTION_ENTRY(_alignment_handler)
+ CLEAR_LWA_FLAG(r3)
/* r4: EA of fault (set by EXCEPTION_HANDLE) */
l.jal do_unaligned_access
l.addi r3,r1,0 /* pt_regs */
@@ -509,6 +519,7 @@ EXCEPTION_ENTRY(_external_irq_handler)
// l.sw PT_SR(r1),r4
1:
#endif
+ CLEAR_LWA_FLAG(r3)
l.addi r3,r1,0
l.movhi r8,hi(do_IRQ)
l.ori r8,r8,lo(do_IRQ)
@@ -556,8 +567,12 @@ ENTRY(_sys_call_handler)
* they should be clobbered, otherwise
*/
l.sw PT_GPR3(r1),r3
- /* r4 already saved */
- /* r4 holds the EEAR address of the fault, load the original r4 */
+ /*
+ * r4 already saved
+ * r4 holds the EEAR address of the fault, use it as screatch reg and
+ * then load the original r4
+ */
+ CLEAR_LWA_FLAG(r4)
l.lwz r4,PT_GPR4(r1)
l.sw PT_GPR5(r1),r5
l.sw PT_GPR6(r1),r6
@@ -776,6 +791,7 @@ UNHANDLED_EXCEPTION(_vector_0xd00,0xd00)
/* ---[ 0xe00: Trap exception ]------------------------------------------ */
EXCEPTION_ENTRY(_trap_handler)
+ CLEAR_LWA_FLAG(r3)
/* r4: EA of fault (set by EXCEPTION_HANDLE) */
l.jal do_trap
l.addi r3,r1,0 /* pt_regs */