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-rw-r--r--arch/powerpc/include/asm/paca.h7
-rw-r--r--arch/powerpc/kernel/exceptions-64e.S343
-rw-r--r--arch/powerpc/mm/tlb_nohash.c11
3 files changed, 300 insertions, 61 deletions
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 948f01a04cc3..8e956a0b6e85 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -116,8 +116,11 @@ struct paca_struct {
/* Shared by all threads of a core -- points to tcd of first thread */
struct tlb_core_data *tcd_ptr;
- /* We can have up to 3 levels of reentrancy in the TLB miss handler */
- u64 extlb[3][EX_TLB_SIZE / sizeof(u64)];
+ /*
+ * We can have up to 3 levels of reentrancy in the TLB miss handler,
+ * in each of four exception levels (normal, crit, mcheck, debug).
+ */
+ u64 extlb[12][EX_TLB_SIZE / sizeof(u64)];
u64 exmc[8]; /* used for machine checks */
u64 excrit[8]; /* used for crit interrupts */
u64 exdbg[8]; /* used for debug interrupts */
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 2beb5bd0728b..c1bee3ce9d1f 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -34,20 +34,250 @@
* special interrupts from within a non-standard level will probably
* blow you up
*/
-#define SPECIAL_EXC_FRAME_SIZE INT_FRAME_SIZE
+#define SPECIAL_EXC_SRR0 0
+#define SPECIAL_EXC_SRR1 1
+#define SPECIAL_EXC_SPRG_GEN 2
+#define SPECIAL_EXC_SPRG_TLB 3
+#define SPECIAL_EXC_MAS0 4
+#define SPECIAL_EXC_MAS1 5
+#define SPECIAL_EXC_MAS2 6
+#define SPECIAL_EXC_MAS3 7
+#define SPECIAL_EXC_MAS6 8
+#define SPECIAL_EXC_MAS7 9
+#define SPECIAL_EXC_MAS5 10 /* E.HV only */
+#define SPECIAL_EXC_MAS8 11 /* E.HV only */
+#define SPECIAL_EXC_IRQHAPPENED 12
+#define SPECIAL_EXC_DEAR 13
+#define SPECIAL_EXC_ESR 14
+#define SPECIAL_EXC_SOFTE 15
+#define SPECIAL_EXC_CSRR0 16
+#define SPECIAL_EXC_CSRR1 17
+/* must be even to keep 16-byte stack alignment */
+#define SPECIAL_EXC_END 18
+
+#define SPECIAL_EXC_FRAME_SIZE (INT_FRAME_SIZE + SPECIAL_EXC_END * 8)
+#define SPECIAL_EXC_FRAME_OFFS (INT_FRAME_SIZE - 288)
+
+#define SPECIAL_EXC_STORE(reg, name) \
+ std reg, (SPECIAL_EXC_##name * 8 + SPECIAL_EXC_FRAME_OFFS)(r1)
+
+#define SPECIAL_EXC_LOAD(reg, name) \
+ ld reg, (SPECIAL_EXC_##name * 8 + SPECIAL_EXC_FRAME_OFFS)(r1)
+
+special_reg_save:
+ lbz r9,PACAIRQHAPPENED(r13)
+ RECONCILE_IRQ_STATE(r3,r4)
-/* Now we only store something to exception thread info */
-#define EXC_LEVEL_EXCEPTION_PROLOG(type) \
- ld r14,PACAKSAVE(r13); \
- CURRENT_THREAD_INFO(r14, r14); \
- CURRENT_THREAD_INFO(r15, r1); \
- ld r10,TI_FLAGS(r14); \
- std r10,TI_FLAGS(r15); \
- ld r10,TI_PREEMPT(r14); \
- std r10,TI_PREEMPT(r15); \
- ld r10,TI_TASK(r14); \
- std r10,TI_TASK(r15);
+ /*
+ * We only need (or have stack space) to save this stuff if
+ * we interrupted the kernel.
+ */
+ ld r3,_MSR(r1)
+ andi. r3,r3,MSR_PR
+ bnelr
+
+ /* Copy info into temporary exception thread info */
+ ld r11,PACAKSAVE(r13)
+ CURRENT_THREAD_INFO(r11, r11)
+ CURRENT_THREAD_INFO(r12, r1)
+ ld r10,TI_FLAGS(r11)
+ std r10,TI_FLAGS(r12)
+ ld r10,TI_PREEMPT(r11)
+ std r10,TI_PREEMPT(r12)
+ ld r10,TI_TASK(r11)
+ std r10,TI_TASK(r12)
+
+ /*
+ * Advance to the next TLB exception frame for handler
+ * types that don't do it automatically.
+ */
+ LOAD_REG_ADDR(r11,extlb_level_exc)
+ lwz r12,0(r11)
+ mfspr r10,SPRN_SPRG_TLB_EXFRAME
+ add r10,r10,r12
+ mtspr SPRN_SPRG_TLB_EXFRAME,r10
+
+ /*
+ * Save registers needed to allow nesting of certain exceptions
+ * (such as TLB misses) inside special exception levels
+ */
+ mfspr r10,SPRN_SRR0
+ SPECIAL_EXC_STORE(r10,SRR0)
+ mfspr r10,SPRN_SRR1
+ SPECIAL_EXC_STORE(r10,SRR1)
+ mfspr r10,SPRN_SPRG_GEN_SCRATCH
+ SPECIAL_EXC_STORE(r10,SPRG_GEN)
+ mfspr r10,SPRN_SPRG_TLB_SCRATCH
+ SPECIAL_EXC_STORE(r10,SPRG_TLB)
+ mfspr r10,SPRN_MAS0
+ SPECIAL_EXC_STORE(r10,MAS0)
+ mfspr r10,SPRN_MAS1
+ SPECIAL_EXC_STORE(r10,MAS1)
+ mfspr r10,SPRN_MAS2
+ SPECIAL_EXC_STORE(r10,MAS2)
+ mfspr r10,SPRN_MAS3
+ SPECIAL_EXC_STORE(r10,MAS3)
+ mfspr r10,SPRN_MAS6
+ SPECIAL_EXC_STORE(r10,MAS6)
+ mfspr r10,SPRN_MAS7
+ SPECIAL_EXC_STORE(r10,MAS7)
+BEGIN_FTR_SECTION
+ mfspr r10,SPRN_MAS5
+ SPECIAL_EXC_STORE(r10,MAS5)
+ mfspr r10,SPRN_MAS8
+ SPECIAL_EXC_STORE(r10,MAS8)
+
+ /* MAS5/8 could have inappropriate values if we interrupted KVM code */
+ li r10,0
+ mtspr SPRN_MAS5,r10
+ mtspr SPRN_MAS8,r10
+END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
+ SPECIAL_EXC_STORE(r9,IRQHAPPENED)
+
+ mfspr r10,SPRN_DEAR
+ SPECIAL_EXC_STORE(r10,DEAR)
+ mfspr r10,SPRN_ESR
+ SPECIAL_EXC_STORE(r10,ESR)
+
+ lbz r10,PACASOFTIRQEN(r13)
+ SPECIAL_EXC_STORE(r10,SOFTE)
+ ld r10,_NIP(r1)
+ SPECIAL_EXC_STORE(r10,CSRR0)
+ ld r10,_MSR(r1)
+ SPECIAL_EXC_STORE(r10,CSRR1)
+
+ blr
+
+ret_from_level_except:
+ ld r3,_MSR(r1)
+ andi. r3,r3,MSR_PR
+ beq 1f
+ b ret_from_except
+1:
+
+ LOAD_REG_ADDR(r11,extlb_level_exc)
+ lwz r12,0(r11)
+ mfspr r10,SPRN_SPRG_TLB_EXFRAME
+ sub r10,r10,r12
+ mtspr SPRN_SPRG_TLB_EXFRAME,r10
+
+ /*
+ * It's possible that the special level exception interrupted a
+ * TLB miss handler, and inserted the same entry that the
+ * interrupted handler was about to insert. On CPUs without TLB
+ * write conditional, this can result in a duplicate TLB entry.
+ * Wipe all non-bolted entries to be safe.
+ *
+ * Note that this doesn't protect against any TLB misses
+ * we may take accessing the stack from here to the end of
+ * the special level exception. It's not clear how we can
+ * reasonably protect against that, but only CPUs with
+ * neither TLB write conditional nor bolted kernel memory
+ * are affected. Do any such CPUs even exist?
+ */
+ PPC_TLBILX_ALL(0,R0)
+
+ REST_NVGPRS(r1)
+
+ SPECIAL_EXC_LOAD(r10,SRR0)
+ mtspr SPRN_SRR0,r10
+ SPECIAL_EXC_LOAD(r10,SRR1)
+ mtspr SPRN_SRR1,r10
+ SPECIAL_EXC_LOAD(r10,SPRG_GEN)
+ mtspr SPRN_SPRG_GEN_SCRATCH,r10
+ SPECIAL_EXC_LOAD(r10,SPRG_TLB)
+ mtspr SPRN_SPRG_TLB_SCRATCH,r10
+ SPECIAL_EXC_LOAD(r10,MAS0)
+ mtspr SPRN_MAS0,r10
+ SPECIAL_EXC_LOAD(r10,MAS1)
+ mtspr SPRN_MAS1,r10
+ SPECIAL_EXC_LOAD(r10,MAS2)
+ mtspr SPRN_MAS2,r10
+ SPECIAL_EXC_LOAD(r10,MAS3)
+ mtspr SPRN_MAS3,r10
+ SPECIAL_EXC_LOAD(r10,MAS6)
+ mtspr SPRN_MAS6,r10
+ SPECIAL_EXC_LOAD(r10,MAS7)
+ mtspr SPRN_MAS7,r10
+BEGIN_FTR_SECTION
+ SPECIAL_EXC_LOAD(r10,MAS5)
+ mtspr SPRN_MAS5,r10
+ SPECIAL_EXC_LOAD(r10,MAS8)
+ mtspr SPRN_MAS8,r10
+END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
+
+ lbz r6,PACASOFTIRQEN(r13)
+ ld r5,SOFTE(r1)
+
+ /* Interrupts had better not already be enabled... */
+ twnei r6,0
+
+ cmpwi cr0,r5,0
+ beq 1f
+ TRACE_ENABLE_INTS
+ stb r5,PACASOFTIRQEN(r13)
+1:
+ /*
+ * Restore PACAIRQHAPPENED rather than setting it based on
+ * the return MSR[EE], since we could have interrupted
+ * __check_irq_replay() or other inconsistent transitory
+ * states that must remain that way.
+ */
+ SPECIAL_EXC_LOAD(r10,IRQHAPPENED)
+ stb r10,PACAIRQHAPPENED(r13)
+
+ SPECIAL_EXC_LOAD(r10,DEAR)
+ mtspr SPRN_DEAR,r10
+ SPECIAL_EXC_LOAD(r10,ESR)
+ mtspr SPRN_ESR,r10
+
+ stdcx. r0,0,r1 /* to clear the reservation */
+
+ REST_4GPRS(2, r1)
+ REST_4GPRS(6, r1)
+
+ ld r10,_CTR(r1)
+ ld r11,_XER(r1)
+ mtctr r10
+ mtxer r11
+
+ blr
+
+.macro ret_from_level srr0 srr1 paca_ex scratch
+ bl ret_from_level_except
+
+ ld r10,_LINK(r1)
+ ld r11,_CCR(r1)
+ ld r0,GPR13(r1)
+ mtlr r10
+ mtcr r11
+
+ ld r10,GPR10(r1)
+ ld r11,GPR11(r1)
+ ld r12,GPR12(r1)
+ mtspr \scratch,r0
+
+ std r10,\paca_ex+EX_R10(r13);
+ std r11,\paca_ex+EX_R11(r13);
+ ld r10,_NIP(r1)
+ ld r11,_MSR(r1)
+ ld r0,GPR0(r1)
+ ld r1,GPR1(r1)
+ mtspr \srr0,r10
+ mtspr \srr1,r11
+ ld r10,\paca_ex+EX_R10(r13)
+ ld r11,\paca_ex+EX_R11(r13)
+ mfspr r13,\scratch
+.endm
+
+ret_from_crit_except:
+ ret_from_level SPRN_CSRR0 SPRN_CSRR1 PACA_EXCRIT SPRN_SPRG_CRIT_SCRATCH
+ rfci
+
+ret_from_mc_except:
+ ret_from_level SPRN_MCSRR0 SPRN_MCSRR1 PACA_EXMC SPRN_SPRG_MC_SCRATCH
+ rfmci
/* Exception prolog code for all exceptions */
#define EXCEPTION_PROLOG(n, intnum, type, addition) \
@@ -81,22 +311,19 @@
#define CRIT_SET_KSTACK \
ld r1,PACA_CRIT_STACK(r13); \
- subi r1,r1,SPECIAL_EXC_FRAME_SIZE; \
- EXC_LEVEL_EXCEPTION_PROLOG(CRIT);
+ subi r1,r1,SPECIAL_EXC_FRAME_SIZE
#define SPRN_CRIT_SRR0 SPRN_CSRR0
#define SPRN_CRIT_SRR1 SPRN_CSRR1
#define DBG_SET_KSTACK \
ld r1,PACA_DBG_STACK(r13); \
- subi r1,r1,SPECIAL_EXC_FRAME_SIZE; \
- EXC_LEVEL_EXCEPTION_PROLOG(DBG);
+ subi r1,r1,SPECIAL_EXC_FRAME_SIZE
#define SPRN_DBG_SRR0 SPRN_DSRR0
#define SPRN_DBG_SRR1 SPRN_DSRR1
#define MC_SET_KSTACK \
ld r1,PACA_MC_STACK(r13); \
- subi r1,r1,SPECIAL_EXC_FRAME_SIZE; \
- EXC_LEVEL_EXCEPTION_PROLOG(MC);
+ subi r1,r1,SPECIAL_EXC_FRAME_SIZE
#define SPRN_MC_SRR0 SPRN_MCSRR0
#define SPRN_MC_SRR1 SPRN_MCSRR1
@@ -322,27 +549,25 @@ interrupt_end_book3e:
START_EXCEPTION(critical_input);
CRIT_EXCEPTION_PROLOG(0x100, BOOKE_INTERRUPT_CRITICAL,
PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON_CRIT(0x100)
-// INTS_DISABLE
-// bl special_reg_save_crit
-// CHECK_NAPPING();
-// addi r3,r1,STACK_FRAME_OVERHEAD
-// bl .critical_exception
-// b ret_from_crit_except
- b .
+ EXCEPTION_COMMON_CRIT(0x100)
+ bl .save_nvgprs
+ bl special_reg_save
+ CHECK_NAPPING();
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .unknown_exception
+ b ret_from_crit_except
/* Machine Check Interrupt */
START_EXCEPTION(machine_check);
MC_EXCEPTION_PROLOG(0x000, BOOKE_INTERRUPT_MACHINE_CHECK,
PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON_MC(0x000)
-// INTS_DISABLE
-// bl special_reg_save_mc
-// addi r3,r1,STACK_FRAME_OVERHEAD
-// CHECK_NAPPING();
-// bl .machine_check_exception
-// b ret_from_mc_except
- b .
+ EXCEPTION_COMMON_MC(0x000)
+ bl .save_nvgprs
+ bl special_reg_save
+ CHECK_NAPPING();
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .machine_check_exception
+ b ret_from_mc_except
/* Data Storage Interrupt */
START_EXCEPTION(data_storage)
@@ -461,14 +686,17 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
START_EXCEPTION(watchdog);
CRIT_EXCEPTION_PROLOG(0x9f0, BOOKE_INTERRUPT_WATCHDOG,
PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON_CRIT(0x9f0)
-// INTS_DISABLE
-// bl special_reg_save_crit
-// CHECK_NAPPING();
-// addi r3,r1,STACK_FRAME_OVERHEAD
-// bl .unknown_exception
-// b ret_from_crit_except
- b .
+ EXCEPTION_COMMON_CRIT(0x9f0)
+ bl .save_nvgprs
+ bl special_reg_save
+ CHECK_NAPPING();
+ addi r3,r1,STACK_FRAME_OVERHEAD
+#ifdef CONFIG_BOOKE_WDT
+ bl .WatchdogException
+#else
+ bl .unknown_exception
+#endif
+ b ret_from_crit_except
/* System Call Interrupt */
START_EXCEPTION(system_call)
@@ -541,7 +769,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
*/
mfspr r14,SPRN_DBSR
EXCEPTION_COMMON_CRIT(0xd00)
- INTS_DISABLE
std r14,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
mr r4,r14
@@ -634,14 +861,13 @@ kernel_dbg_exc:
START_EXCEPTION(doorbell_crit);
CRIT_EXCEPTION_PROLOG(0x2a0, BOOKE_INTERRUPT_DOORBELL_CRITICAL,
PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON_CRIT(0x2a0)
-// INTS_DISABLE
-// bl special_reg_save_crit
-// CHECK_NAPPING();
-// addi r3,r1,STACK_FRAME_OVERHEAD
-// bl .doorbell_critical_exception
-// b ret_from_crit_except
- b .
+ EXCEPTION_COMMON_CRIT(0x2a0)
+ bl .save_nvgprs
+ bl special_reg_save
+ CHECK_NAPPING();
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .unknown_exception
+ b ret_from_crit_except
/*
* Guest doorbell interrupt
@@ -661,14 +887,13 @@ kernel_dbg_exc:
START_EXCEPTION(guest_doorbell_crit);
CRIT_EXCEPTION_PROLOG(0x2e0, BOOKE_INTERRUPT_GUEST_DBELL_CRIT,
PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON_CRIT(0x2e0)
-// INTS_DISABLE
-// bl special_reg_save_crit
-// CHECK_NAPPING();
-// addi r3,r1,STACK_FRAME_OVERHEAD
-// bl .guest_doorbell_critical_exception
-// b ret_from_crit_except
- b .
+ EXCEPTION_COMMON_CRIT(0x2e0)
+ bl .save_nvgprs
+ bl special_reg_save
+ CHECK_NAPPING();
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .unknown_exception
+ b ret_from_crit_except
/* Hypervisor call */
START_EXCEPTION(hypercall);
diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c
index b37a58e1c92d..ae3d5b799b90 100644
--- a/arch/powerpc/mm/tlb_nohash.c
+++ b/arch/powerpc/mm/tlb_nohash.c
@@ -144,6 +144,15 @@ int mmu_vmemmap_psize; /* Page size used for the virtual mem map */
int book3e_htw_mode; /* HW tablewalk? Value is PPC_HTW_* */
unsigned long linear_map_top; /* Top of linear mapping */
+
+/*
+ * Number of bytes to add to SPRN_SPRG_TLB_EXFRAME on crit/mcheck/debug
+ * exceptions. This is used for bolted and e6500 TLB miss handlers which
+ * do not modify this SPRG in the TLB miss code; for other TLB miss handlers,
+ * this is set to zero.
+ */
+int extlb_level_exc;
+
#endif /* CONFIG_PPC64 */
#ifdef CONFIG_PPC_FSL_BOOK3E
@@ -559,6 +568,7 @@ static void setup_mmu_htw(void)
break;
#ifdef CONFIG_PPC_FSL_BOOK3E
case PPC_HTW_E6500:
+ extlb_level_exc = EX_TLB_SIZE;
patch_exception(0x1c0, exc_data_tlb_miss_e6500_book3e);
patch_exception(0x1e0, exc_instruction_tlb_miss_e6500_book3e);
break;
@@ -652,6 +662,7 @@ static void __early_init_mmu(int boot_cpu)
memblock_enforce_memory_limit(linear_map_top);
if (book3e_htw_mode == PPC_HTW_NONE) {
+ extlb_level_exc = EX_TLB_SIZE;
patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e);
patch_exception(0x1e0,
exc_instruction_tlb_miss_bolted_book3e);