summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r--arch/powerpc/kernel/asm-offsets.c2
-rw-r--r--arch/powerpc/kernel/dbell.c2
-rw-r--r--arch/powerpc/kernel/entry_64.S153
-rw-r--r--arch/powerpc/kernel/exceptions-64e.S221
-rw-r--r--arch/powerpc/kernel/exceptions-64s.S150
-rw-r--r--arch/powerpc/kernel/head_64.S24
-rw-r--r--arch/powerpc/kernel/idle.c6
-rw-r--r--arch/powerpc/kernel/idle_book3e.S25
-rw-r--r--arch/powerpc/kernel/idle_power4.S24
-rw-r--r--arch/powerpc/kernel/idle_power7.S23
-rw-r--r--arch/powerpc/kernel/irq.c204
-rw-r--r--arch/powerpc/kernel/process.c3
-rw-r--r--arch/powerpc/kernel/time.c8
13 files changed, 551 insertions, 294 deletions
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 04caee7d9bc1..cdd0d264415f 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -147,7 +147,7 @@ int main(void)
DEFINE(PACAKBASE, offsetof(struct paca_struct, kernelbase));
DEFINE(PACAKMSR, offsetof(struct paca_struct, kernel_msr));
DEFINE(PACASOFTIRQEN, offsetof(struct paca_struct, soft_enabled));
- DEFINE(PACAHARDIRQEN, offsetof(struct paca_struct, hard_enabled));
+ DEFINE(PACAIRQHAPPENED, offsetof(struct paca_struct, irq_happened));
DEFINE(PACACONTEXTID, offsetof(struct paca_struct, context.id));
#ifdef CONFIG_PPC_MM_SLICES
DEFINE(PACALOWSLICESPSIZE, offsetof(struct paca_struct,
diff --git a/arch/powerpc/kernel/dbell.c b/arch/powerpc/kernel/dbell.c
index 2cc451aaaca7..5b25c8060fd6 100644
--- a/arch/powerpc/kernel/dbell.c
+++ b/arch/powerpc/kernel/dbell.c
@@ -37,6 +37,8 @@ void doorbell_exception(struct pt_regs *regs)
irq_enter();
+ may_hard_irq_enable();
+
smp_ipi_demux();
irq_exit();
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index c513beb78b3b..f8a7a1a1a9f4 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -32,6 +32,7 @@
#include <asm/ptrace.h>
#include <asm/irqflags.h>
#include <asm/ftrace.h>
+#include <asm/hw_irq.h>
/*
* System calls.
@@ -583,18 +584,72 @@ _GLOBAL(ret_from_except_lite)
bne do_work
#endif /* !CONFIG_PREEMPT */
+ .globl fast_exc_return_irq
+fast_exc_return_irq:
restore:
+ /*
+ * This is the main kernel exit path, we first check if we
+ * have to change our interrupt state.
+ */
ld r5,SOFTE(r1)
- TRACE_AND_RESTORE_IRQ(r5);
+ lbz r6,PACASOFTIRQEN(r13)
+ cmpwi cr1,r5,0
+ cmpw cr0,r5,r6
+ beq cr0,4f
+
+ /* We do, handle disable first, which is easy */
+ bne cr1,3f;
+ li r0,0
+ stb r0,PACASOFTIRQEN(r13);
+ TRACE_DISABLE_INTS
+ b 4f
- /* extract EE bit and use it to restore paca->hard_enabled */
- ld r3,_MSR(r1)
- rldicl r4,r3,49,63 /* r0 = (r3 >> 15) & 1 */
- stb r4,PACAHARDIRQEN(r13)
+3: /*
+ * We are about to soft-enable interrupts (we are hard disabled
+ * at this point). We check if there's anything that needs to
+ * be replayed first.
+ */
+ lbz r0,PACAIRQHAPPENED(r13)
+ cmpwi cr0,r0,0
+ bne- restore_check_irq_replay
+
+ /*
+ * Get here when nothing happened while soft-disabled, just
+ * soft-enable and move-on. We will hard-enable as a side
+ * effect of rfi
+ */
+restore_no_replay:
+ TRACE_ENABLE_INTS
+ li r0,1
+ stb r0,PACASOFTIRQEN(r13);
+ /*
+ * Final return path. BookE is handled in a different file
+ */
+4:
#ifdef CONFIG_PPC_BOOK3E
b .exception_return_book3e
#else
+ /*
+ * Clear the reservation. If we know the CPU tracks the address of
+ * the reservation then we can potentially save some cycles and use
+ * a larx. On POWER6 and POWER7 this is significantly faster.
+ */
+BEGIN_FTR_SECTION
+ stdcx. r0,0,r1 /* to clear the reservation */
+FTR_SECTION_ELSE
+ ldarx r4,0,r1
+ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
+
+ /*
+ * Some code path such as load_up_fpu or altivec return directly
+ * here. They run entirely hard disabled and do not alter the
+ * interrupt state. They also don't use lwarx/stwcx. and thus
+ * are known not to leave dangling reservations.
+ */
+ .globl fast_exception_return
+fast_exception_return:
+ ld r3,_MSR(r1)
ld r4,_CTR(r1)
ld r0,_LINK(r1)
mtctr r4
@@ -608,17 +663,6 @@ restore:
beq- unrecov_restore
/*
- * Clear the reservation. If we know the CPU tracks the address of
- * the reservation then we can potentially save some cycles and use
- * a larx. On POWER6 and POWER7 this is significantly faster.
- */
-BEGIN_FTR_SECTION
- stdcx. r0,0,r1 /* to clear the reservation */
-FTR_SECTION_ELSE
- ldarx r4,0,r1
-ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
-
- /*
* Clear RI before restoring r13. If we are returning to
* userspace and we take an exception after restoring r13,
* we end up corrupting the userspace r13 value.
@@ -629,7 +673,8 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
/*
* r13 is our per cpu area, only restore it if we are returning to
- * userspace
+ * userspace the value stored in the stack frame may belong to
+ * another CPU.
*/
andi. r0,r3,MSR_PR
beq 1f
@@ -654,6 +699,55 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
#endif /* CONFIG_PPC_BOOK3E */
+ /*
+ * Something did happen, check if a re-emit is needed
+ * (this also clears paca->irq_happened)
+ */
+restore_check_irq_replay:
+ /* XXX: We could implement a fast path here where we check
+ * for irq_happened being just 0x01, in which case we can
+ * clear it and return. That means that we would potentially
+ * miss a decrementer having wrapped all the way around.
+ *
+ * Still, this might be useful for things like hash_page
+ */
+ bl .__check_irq_replay
+ cmpwi cr0,r3,0
+ beq restore_no_replay
+
+ /*
+ * We need to re-emit an interrupt. We do so by re-using our
+ * existing exception frame. We first change the trap value,
+ * but we need to ensure we preserve the low nibble of it
+ */
+ ld r4,_TRAP(r1)
+ clrldi r4,r4,60
+ or r4,r4,r3
+ std r4,_TRAP(r1)
+
+ /*
+ * Then find the right handler and call it. Interrupts are
+ * still soft-disabled and we keep them that way.
+ */
+ cmpwi cr0,r3,0x500
+ bne 1f
+ addi r3,r1,STACK_FRAME_OVERHEAD;
+ bl .do_IRQ
+ b .ret_from_except
+1: cmpwi cr0,r3,0x900
+ bne 1f
+ addi r3,r1,STACK_FRAME_OVERHEAD;
+ bl .timer_interrupt
+ b .ret_from_except
+#ifdef CONFIG_PPC_BOOK3E
+1: cmpwi cr0,r3,0x280
+ bne 1f
+ addi r3,r1,STACK_FRAME_OVERHEAD;
+ bl .doorbell_exception
+ b .ret_from_except
+#endif /* CONFIG_PPC_BOOK3E */
+1: b .ret_from_except /* What else to do here ? */
+
do_work:
#ifdef CONFIG_PREEMPT
andi. r0,r3,MSR_PR /* Returning to user mode? */
@@ -666,18 +760,11 @@ do_work:
crandc eq,cr1*4+eq,eq
bne restore
- /* Here we are preempting the current task.
- *
- * Ensure interrupts are soft-disabled. We also properly mark
- * the PACA to reflect the fact that they are hard-disabled
- * and trace the change
+ /*
+ * Here we are preempting the current task. We want to make
+ * sure we are soft-disabled first
*/
- li r0,0
- stb r0,PACASOFTIRQEN(r13)
- stb r0,PACAHARDIRQEN(r13)
- TRACE_DISABLE_INTS
-
- /* Call the scheduler with soft IRQs off */
+ SOFT_DISABLE_INTS(r3,r4)
1: bl .preempt_schedule_irq
/* Hard-disable interrupts again (and update PACA) */
@@ -687,8 +774,8 @@ do_work:
ld r10,PACAKMSR(r13) /* Get kernel MSR without EE */
mtmsrd r10,1
#endif /* CONFIG_PPC_BOOK3E */
- li r0,0
- stb r0,PACAHARDIRQEN(r13)
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
/* Re-test flags and eventually loop */
clrrdi r9,r1,THREAD_SHIFT
@@ -710,14 +797,12 @@ user_work:
andi. r0,r4,_TIF_NEED_RESCHED
beq 1f
- li r5,1
- TRACE_AND_RESTORE_IRQ(r5);
+ bl .restore_interrupts
bl .schedule
b .ret_from_except_lite
1: bl .save_nvgprs
- li r5,1
- TRACE_AND_RESTORE_IRQ(r5);
+ bl .restore_interrupts
addi r3,r1,STACK_FRAME_OVERHEAD
bl .do_notify_resume
b .ret_from_except
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index c4c34665c221..7215cc2495df 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -24,6 +24,7 @@
#include <asm/ptrace.h>
#include <asm/ppc-opcode.h>
#include <asm/mmu.h>
+#include <asm/hw_irq.h>
/* XXX This will ultimately add space for a special exception save
* structure used to save things like SRR0/SRR1, SPRGs, MAS, etc...
@@ -77,59 +78,55 @@
#define SPRN_MC_SRR1 SPRN_MCSRR1
#define NORMAL_EXCEPTION_PROLOG(n, addition) \
- EXCEPTION_PROLOG(n, GEN, addition##_GEN)
+ EXCEPTION_PROLOG(n, GEN, addition##_GEN(n))
#define CRIT_EXCEPTION_PROLOG(n, addition) \
- EXCEPTION_PROLOG(n, CRIT, addition##_CRIT)
+ EXCEPTION_PROLOG(n, CRIT, addition##_CRIT(n))
#define DBG_EXCEPTION_PROLOG(n, addition) \
- EXCEPTION_PROLOG(n, DBG, addition##_DBG)
+ EXCEPTION_PROLOG(n, DBG, addition##_DBG(n))
#define MC_EXCEPTION_PROLOG(n, addition) \
- EXCEPTION_PROLOG(n, MC, addition##_MC)
+ EXCEPTION_PROLOG(n, MC, addition##_MC(n))
/* Variants of the "addition" argument for the prolog
*/
-#define PROLOG_ADDITION_NONE_GEN
-#define PROLOG_ADDITION_NONE_CRIT
-#define PROLOG_ADDITION_NONE_DBG
-#define PROLOG_ADDITION_NONE_MC
+#define PROLOG_ADDITION_NONE_GEN(n)
+#define PROLOG_ADDITION_NONE_CRIT(n)
+#define PROLOG_ADDITION_NONE_DBG(n)
+#define PROLOG_ADDITION_NONE_MC(n)
-#define PROLOG_ADDITION_MASKABLE_GEN \
+#define PROLOG_ADDITION_MASKABLE_GEN(n) \
lbz r11,PACASOFTIRQEN(r13); /* are irqs soft-disabled ? */ \
cmpwi cr0,r11,0; /* yes -> go out of line */ \
- beq masked_interrupt_book3e;
+ beq masked_interrupt_book3e_##n
-#define PROLOG_ADDITION_2REGS_GEN \
+#define PROLOG_ADDITION_2REGS_GEN(n) \
std r14,PACA_EXGEN+EX_R14(r13); \
std r15,PACA_EXGEN+EX_R15(r13)
-#define PROLOG_ADDITION_1REG_GEN \
+#define PROLOG_ADDITION_1REG_GEN(n) \
std r14,PACA_EXGEN+EX_R14(r13);
-#define PROLOG_ADDITION_2REGS_CRIT \
+#define PROLOG_ADDITION_2REGS_CRIT(n) \
std r14,PACA_EXCRIT+EX_R14(r13); \
std r15,PACA_EXCRIT+EX_R15(r13)
-#define PROLOG_ADDITION_2REGS_DBG \
+#define PROLOG_ADDITION_2REGS_DBG(n) \
std r14,PACA_EXDBG+EX_R14(r13); \
std r15,PACA_EXDBG+EX_R15(r13)
-#define PROLOG_ADDITION_2REGS_MC \
+#define PROLOG_ADDITION_2REGS_MC(n) \
std r14,PACA_EXMC+EX_R14(r13); \
std r15,PACA_EXMC+EX_R15(r13)
-#define PROLOG_ADDITION_DOORBELL_GEN \
- lbz r11,PACASOFTIRQEN(r13); /* are irqs soft-disabled ? */ \
- cmpwi cr0,r11,0; /* yes -> go out of line */ \
- beq masked_doorbell_book3e
-
/* Core exception code for all exceptions except TLB misses.
* XXX: Needs to make SPRN_SPRG_GEN depend on exception type
*/
#define EXCEPTION_COMMON(n, excf, ints) \
+exc_##n##_common: \
std r0,GPR0(r1); /* save r0 in stackframe */ \
std r2,GPR2(r1); /* save r2 in stackframe */ \
SAVE_4GPRS(3, r1); /* save r3 - r6 in stackframe */ \
@@ -167,20 +164,21 @@
std r0,RESULT(r1); /* clear regs->result */ \
ints;
-/* Variants for the "ints" argument */
+/* Variants for the "ints" argument. This one does nothing when we want
+ * to keep interrupts in their original state
+ */
#define INTS_KEEP
-#define INTS_DISABLE_SOFT \
- stb r0,PACASOFTIRQEN(r13); /* mark interrupts soft-disabled */ \
- TRACE_DISABLE_INTS;
-#define INTS_DISABLE_HARD \
- stb r0,PACAHARDIRQEN(r13); /* and hard disabled */
-#define INTS_DISABLE_ALL \
- INTS_DISABLE_SOFT \
- INTS_DISABLE_HARD
-
-/* This is called by exceptions that used INTS_KEEP (that is did not clear
- * neither soft nor hard IRQ indicators in the PACA. This will restore MSR:EE
- * to it's previous value
+
+/* This second version is meant for exceptions that don't immediately
+ * hard-enable. We set a bit in paca->irq_happened to ensure that
+ * a subsequent call to arch_local_irq_restore() will properly
+ * hard-enable and avoid the fast-path
+ */
+#define INTS_DISABLE SOFT_DISABLE_INTS(r3,r4)
+
+/* This is called by exceptions that used INTS_KEEP (that did not touch
+ * irq indicators in the PACA). This will restore MSR:EE to it's previous
+ * value
*
* XXX In the long run, we may want to open-code it in order to separate the
* load from the wrtee, thus limiting the latency caused by the dependency
@@ -238,7 +236,7 @@ exc_##n##_bad_stack: \
#define MASKABLE_EXCEPTION(trapnum, label, hdlr, ack) \
START_EXCEPTION(label); \
NORMAL_EXCEPTION_PROLOG(trapnum, PROLOG_ADDITION_MASKABLE) \
- EXCEPTION_COMMON(trapnum, PACA_EXGEN, INTS_DISABLE_ALL) \
+ EXCEPTION_COMMON(trapnum, PACA_EXGEN, INTS_DISABLE) \
ack(r8); \
CHECK_NAPPING(); \
addi r3,r1,STACK_FRAME_OVERHEAD; \
@@ -289,7 +287,7 @@ interrupt_end_book3e:
/* Critical Input Interrupt */
START_EXCEPTION(critical_input);
CRIT_EXCEPTION_PROLOG(0x100, PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON(0x100, PACA_EXCRIT, INTS_DISABLE_ALL)
+// EXCEPTION_COMMON(0x100, PACA_EXCRIT, INTS_DISABLE)
// bl special_reg_save_crit
// CHECK_NAPPING();
// addi r3,r1,STACK_FRAME_OVERHEAD
@@ -300,7 +298,7 @@ interrupt_end_book3e:
/* Machine Check Interrupt */
START_EXCEPTION(machine_check);
CRIT_EXCEPTION_PROLOG(0x200, PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON(0x200, PACA_EXMC, INTS_DISABLE_ALL)
+// EXCEPTION_COMMON(0x200, PACA_EXMC, INTS_DISABLE)
// bl special_reg_save_mc
// addi r3,r1,STACK_FRAME_OVERHEAD
// CHECK_NAPPING();
@@ -313,7 +311,7 @@ interrupt_end_book3e:
NORMAL_EXCEPTION_PROLOG(0x300, PROLOG_ADDITION_2REGS)
mfspr r14,SPRN_DEAR
mfspr r15,SPRN_ESR
- EXCEPTION_COMMON(0x300, PACA_EXGEN, INTS_DISABLE_ALL)
+ EXCEPTION_COMMON(0x300, PACA_EXGEN, INTS_DISABLE)
b storage_fault_common
/* Instruction Storage Interrupt */
@@ -321,7 +319,7 @@ interrupt_end_book3e:
NORMAL_EXCEPTION_PROLOG(0x400, PROLOG_ADDITION_2REGS)
li r15,0
mr r14,r10
- EXCEPTION_COMMON(0x400, PACA_EXGEN, INTS_DISABLE_ALL)
+ EXCEPTION_COMMON(0x400, PACA_EXGEN, INTS_DISABLE)
b storage_fault_common
/* External Input Interrupt */
@@ -339,12 +337,11 @@ interrupt_end_book3e:
START_EXCEPTION(program);
NORMAL_EXCEPTION_PROLOG(0x700, PROLOG_ADDITION_1REG)
mfspr r14,SPRN_ESR
- EXCEPTION_COMMON(0x700, PACA_EXGEN, INTS_DISABLE_SOFT)
+ EXCEPTION_COMMON(0x700, PACA_EXGEN, INTS_DISABLE)
std r14,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
ld r14,PACA_EXGEN+EX_R14(r13)
bl .save_nvgprs
- INTS_RESTORE_HARD
bl .program_check_exception
b .ret_from_except
@@ -358,7 +355,7 @@ interrupt_end_book3e:
beq- 1f
bl .load_up_fpu
b fast_exception_return
-1: INTS_DISABLE_ALL
+1: INTS_DISABLE
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .kernel_fp_unavailable_exception
@@ -373,7 +370,7 @@ interrupt_end_book3e:
/* Watchdog Timer Interrupt */
START_EXCEPTION(watchdog);
CRIT_EXCEPTION_PROLOG(0x9f0, PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON(0x9f0, PACA_EXCRIT, INTS_DISABLE_ALL)
+// EXCEPTION_COMMON(0x9f0, PACA_EXCRIT, INTS_DISABLE)
// bl special_reg_save_crit
// CHECK_NAPPING();
// addi r3,r1,STACK_FRAME_OVERHEAD
@@ -392,7 +389,7 @@ interrupt_end_book3e:
/* Auxiliary Processor Unavailable Interrupt */
START_EXCEPTION(ap_unavailable);
NORMAL_EXCEPTION_PROLOG(0xf20, PROLOG_ADDITION_NONE)
- EXCEPTION_COMMON(0xf20, PACA_EXGEN, INTS_DISABLE_ALL)
+ EXCEPTION_COMMON(0xf20, PACA_EXGEN, INTS_DISABLE)
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .unknown_exception
@@ -450,7 +447,7 @@ interrupt_end_book3e:
mfspr r15,SPRN_SPRG_CRIT_SCRATCH
mtspr SPRN_SPRG_GEN_SCRATCH,r15
mfspr r14,SPRN_DBSR
- EXCEPTION_COMMON(0xd00, PACA_EXCRIT, INTS_DISABLE_ALL)
+ EXCEPTION_COMMON(0xd00, PACA_EXCRIT, INTS_DISABLE)
std r14,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
mr r4,r14
@@ -465,7 +462,7 @@ kernel_dbg_exc:
/* Debug exception as a debug interrupt*/
START_EXCEPTION(debug_debug);
- DBG_EXCEPTION_PROLOG(0xd00, PROLOG_ADDITION_2REGS)
+ DBG_EXCEPTION_PROLOG(0xd08, PROLOG_ADDITION_2REGS)
/*
* If there is a single step or branch-taken exception in an
@@ -515,7 +512,7 @@ kernel_dbg_exc:
mfspr r15,SPRN_SPRG_DBG_SCRATCH
mtspr SPRN_SPRG_GEN_SCRATCH,r15
mfspr r14,SPRN_DBSR
- EXCEPTION_COMMON(0xd00, PACA_EXDBG, INTS_DISABLE_ALL)
+ EXCEPTION_COMMON(0xd08, PACA_EXDBG, INTS_DISABLE)
std r14,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
mr r4,r14
@@ -525,21 +522,20 @@ kernel_dbg_exc:
bl .DebugException
b .ret_from_except
- MASKABLE_EXCEPTION(0x260, perfmon, .performance_monitor_exception, ACK_NONE)
-
-/* Doorbell interrupt */
- START_EXCEPTION(doorbell)
- NORMAL_EXCEPTION_PROLOG(0x2070, PROLOG_ADDITION_DOORBELL)
- EXCEPTION_COMMON(0x2070, PACA_EXGEN, INTS_DISABLE_ALL)
- CHECK_NAPPING()
+ START_EXCEPTION(perfmon);
+ NORMAL_EXCEPTION_PROLOG(0x260, PROLOG_ADDITION_NONE)
+ EXCEPTION_COMMON(0x260, PACA_EXGEN, INTS_DISABLE)
addi r3,r1,STACK_FRAME_OVERHEAD
- bl .doorbell_exception
+ bl .performance_monitor_exception
b .ret_from_except_lite
+/* Doorbell interrupt */
+ MASKABLE_EXCEPTION(0x280, doorbell, .doorbell_exception, ACK_NONE)
+
/* Doorbell critical Interrupt */
START_EXCEPTION(doorbell_crit);
- CRIT_EXCEPTION_PROLOG(0x2080, PROLOG_ADDITION_NONE)
-// EXCEPTION_COMMON(0x2080, PACA_EXCRIT, INTS_DISABLE_ALL)
+ CRIT_EXCEPTION_PROLOG(0x2a0, PROLOG_ADDITION_NONE)
+// EXCEPTION_COMMON(0x2a0, PACA_EXCRIT, INTS_DISABLE)
// bl special_reg_save_crit
// CHECK_NAPPING();
// addi r3,r1,STACK_FRAME_OVERHEAD
@@ -547,36 +543,114 @@ kernel_dbg_exc:
// b ret_from_crit_except
b .
+/* Guest Doorbell */
MASKABLE_EXCEPTION(0x2c0, guest_doorbell, .unknown_exception, ACK_NONE)
- MASKABLE_EXCEPTION(0x2e0, guest_doorbell_crit, .unknown_exception, ACK_NONE)
- MASKABLE_EXCEPTION(0x310, hypercall, .unknown_exception, ACK_NONE)
- MASKABLE_EXCEPTION(0x320, ehpriv, .unknown_exception, ACK_NONE)
+/* Guest Doorbell critical Interrupt */
+ START_EXCEPTION(guest_doorbell_crit);
+ CRIT_EXCEPTION_PROLOG(0x2e0, PROLOG_ADDITION_NONE)
+// EXCEPTION_COMMON(0x2e0, PACA_EXCRIT, 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 .
+
+/* Hypervisor call */
+ START_EXCEPTION(hypercall);
+ NORMAL_EXCEPTION_PROLOG(0x310, PROLOG_ADDITION_NONE)
+ EXCEPTION_COMMON(0x310, PACA_EXGEN, INTS_KEEP)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .save_nvgprs
+ INTS_RESTORE_HARD
+ bl .unknown_exception
+ b .ret_from_except
+
+/* Embedded Hypervisor priviledged */
+ START_EXCEPTION(ehpriv);
+ NORMAL_EXCEPTION_PROLOG(0x320, PROLOG_ADDITION_NONE)
+ EXCEPTION_COMMON(0x320, PACA_EXGEN, INTS_KEEP)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .save_nvgprs
+ INTS_RESTORE_HARD
+ bl .unknown_exception
+ b .ret_from_except
/*
- * An interrupt came in while soft-disabled; clear EE in SRR1,
- * clear paca->hard_enabled and return.
+ * An interrupt came in while soft-disabled; We mark paca->irq_happened
+ * accordingly and if the interrupt is level sensitive, we hard disable
*/
-masked_doorbell_book3e:
- mtcr r10
- /* Resend the doorbell to fire again when ints enabled */
- mfspr r10,SPRN_PIR
- PPC_MSGSND(r10)
- b masked_interrupt_book3e_common
-masked_interrupt_book3e:
+masked_interrupt_book3e_0x500:
+ /* XXX When adding support for EPR, use PACA_IRQ_EE_EDGE */
+ li r11,PACA_IRQ_EE
+ b masked_interrupt_book3e_full_mask
+
+masked_interrupt_book3e_0x900:
+ ACK_DEC(r11);
+ li r11,PACA_IRQ_DEC
+ b masked_interrupt_book3e_no_mask
+masked_interrupt_book3e_0x980:
+ ACK_FIT(r11);
+ li r11,PACA_IRQ_DEC
+ b masked_interrupt_book3e_no_mask
+masked_interrupt_book3e_0x280:
+masked_interrupt_book3e_0x2c0:
+ li r11,PACA_IRQ_DBELL
+ b masked_interrupt_book3e_no_mask
+
+masked_interrupt_book3e_no_mask:
mtcr r10
-masked_interrupt_book3e_common:
- stb r11,PACAHARDIRQEN(r13)
+ lbz r10,PACAIRQHAPPENED(r13)
+ or r10,r10,r11
+ stb r10,PACAIRQHAPPENED(r13)
+ b 1f
+masked_interrupt_book3e_full_mask:
+ mtcr r10
+ lbz r10,PACAIRQHAPPENED(r13)
+ or r10,r10,r11
+ stb r10,PACAIRQHAPPENED(r13)
mfspr r10,SPRN_SRR1
rldicl r11,r10,48,1 /* clear MSR_EE */
rotldi r10,r11,16
mtspr SPRN_SRR1,r10
- ld r10,PACA_EXGEN+EX_R10(r13); /* restore registers */
+1: ld r10,PACA_EXGEN+EX_R10(r13);
ld r11,PACA_EXGEN+EX_R11(r13);
mfspr r13,SPRN_SPRG_GEN_SCRATCH;
rfi
b .
+/*
+ * Called from arch_local_irq_enable when an interrupt needs
+ * to be resent. r3 contains either 0x500,0x900,0x260 or 0x280
+ * to indicate the kind of interrupt. MSR:EE is already off.
+ * We generate a stackframe like if a real interrupt had happened.
+ *
+ * Note: While MSR:EE is off, we need to make sure that _MSR
+ * in the generated frame has EE set to 1 or the exception
+ * handler will not properly re-enable them.
+ */
+_GLOBAL(__replay_interrupt)
+ /* We are going to jump to the exception common code which
+ * will retrieve various register values from the PACA which
+ * we don't give a damn about.
+ */
+ mflr r10
+ mfmsr r11
+ mfcr r4
+ mtspr SPRN_SPRG_GEN_SCRATCH,r13;
+ std r1,PACA_EXGEN+EX_R1(r13);
+ stw r4,PACA_EXGEN+EX_CR(r13);
+ ori r11,r11,MSR_EE
+ subi r1,r1,INT_FRAME_SIZE;
+ cmpwi cr0,r3,0x500
+ beq exc_0x500_common
+ cmpwi cr0,r3,0x900
+ beq exc_0x900_common
+ cmpwi cr0,r3,0x280
+ beq exc_0x280_common
+ blr
+
/*
* This is called from 0x300 and 0x400 handlers after the prologs with
@@ -679,6 +753,8 @@ BAD_STACK_TRAMPOLINE(0x000)
BAD_STACK_TRAMPOLINE(0x100)
BAD_STACK_TRAMPOLINE(0x200)
BAD_STACK_TRAMPOLINE(0x260)
+BAD_STACK_TRAMPOLINE(0x280)
+BAD_STACK_TRAMPOLINE(0x2a0)
BAD_STACK_TRAMPOLINE(0x2c0)
BAD_STACK_TRAMPOLINE(0x2e0)
BAD_STACK_TRAMPOLINE(0x300)
@@ -696,11 +772,10 @@ BAD_STACK_TRAMPOLINE(0xa00)
BAD_STACK_TRAMPOLINE(0xb00)
BAD_STACK_TRAMPOLINE(0xc00)
BAD_STACK_TRAMPOLINE(0xd00)
+BAD_STACK_TRAMPOLINE(0xd08)
BAD_STACK_TRAMPOLINE(0xe00)
BAD_STACK_TRAMPOLINE(0xf00)
BAD_STACK_TRAMPOLINE(0xf20)
-BAD_STACK_TRAMPOLINE(0x2070)
-BAD_STACK_TRAMPOLINE(0x2080)
.globl bad_stack_book3e
bad_stack_book3e:
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 02448ea58ad3..2d0868a4e2f0 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -12,6 +12,7 @@
*
*/
+#include <asm/hw_irq.h>
#include <asm/exception-64s.h>
#include <asm/ptrace.h>
@@ -356,34 +357,60 @@ do_stab_bolted_pSeries:
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf40)
/*
- * An interrupt came in while soft-disabled; clear EE in SRR1,
- * clear paca->hard_enabled and return.
+ * An interrupt came in while soft-disabled. We set paca->irq_happened,
+ * then, if it was a decrementer interrupt, we bump the dec to max and
+ * and return, else we hard disable and return. This is called with
+ * r10 containing the value to OR to the paca field.
*/
-masked_interrupt:
- stb r10,PACAHARDIRQEN(r13)
- mtcrf 0x80,r9
- ld r9,PACA_EXGEN+EX_R9(r13)
- mfspr r10,SPRN_SRR1
- rldicl r10,r10,48,1 /* clear MSR_EE */
- rotldi r10,r10,16
- mtspr SPRN_SRR1,r10
- ld r10,PACA_EXGEN+EX_R10(r13)
- GET_SCRATCH0(r13)
- rfid
+#define MASKED_INTERRUPT(_H) \
+masked_##_H##interrupt: \
+ std r11,PACA_EXGEN+EX_R11(r13); \
+ lbz r11,PACAIRQHAPPENED(r13); \
+ or r11,r11,r10; \
+ stb r11,PACAIRQHAPPENED(r13); \
+ andi. r10,r10,PACA_IRQ_DEC; \
+ beq 1f; \
+ lis r10,0x7fff; \
+ ori r10,r10,0xffff; \
+ mtspr SPRN_DEC,r10; \
+ b 2f; \
+1: mfspr r10,SPRN_##_H##SRR1; \
+ rldicl r10,r10,48,1; /* clear MSR_EE */ \
+ rotldi r10,r10,16; \
+ mtspr SPRN_##_H##SRR1,r10; \
+2: mtcrf 0x80,r9; \
+ ld r9,PACA_EXGEN+EX_R9(r13); \
+ ld r10,PACA_EXGEN+EX_R10(r13); \
+ ld r11,PACA_EXGEN+EX_R11(r13); \
+ GET_SCRATCH0(r13); \
+ ##_H##rfid; \
b .
+
+ MASKED_INTERRUPT()
+ MASKED_INTERRUPT(H)
-masked_Hinterrupt:
- stb r10,PACAHARDIRQEN(r13)
- mtcrf 0x80,r9
- ld r9,PACA_EXGEN+EX_R9(r13)
- mfspr r10,SPRN_HSRR1
- rldicl r10,r10,48,1 /* clear MSR_EE */
- rotldi r10,r10,16
- mtspr SPRN_HSRR1,r10
- ld r10,PACA_EXGEN+EX_R10(r13)
- GET_SCRATCH0(r13)
- hrfid
- b .
+/*
+ * Called from arch_local_irq_enable when an interrupt needs
+ * to be resent. r3 contains 0x500 or 0x900 to indicate which
+ * kind of interrupt. MSR:EE is already off. We generate a
+ * stackframe like if a real interrupt had happened.
+ *
+ * Note: While MSR:EE is off, we need to make sure that _MSR
+ * in the generated frame has EE set to 1 or the exception
+ * handler will not properly re-enable them.
+ */
+_GLOBAL(__replay_interrupt)
+ /* We are going to jump to the exception common code which
+ * will retrieve various register values from the PACA which
+ * we don't give a damn about, so we don't bother storing them.
+ */
+ mfmsr r12
+ mflr r11
+ mfcr r9
+ ori r12,r12,MSR_EE
+ andi. r3,r3,0x0800
+ bne decrementer_common
+ b hardware_interrupt_common
#ifdef CONFIG_PPC_PSERIES
/*
@@ -793,7 +820,8 @@ vsx_unavailable_common:
EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
#ifdef CONFIG_VSX
BEGIN_FTR_SECTION
- bne .load_up_vsx
+ beq 1f
+ b .load_up_vsx
1:
END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif
@@ -808,65 +836,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
__end_handlers:
/*
- * Return from an exception with minimal checks.
- * The caller is assumed to have done EXCEPTION_PROLOG_COMMON.
- * If interrupts have been enabled, or anything has been
- * done that might have changed the scheduling status of
- * any task or sent any task a signal, you should use
- * ret_from_except or ret_from_except_lite instead of this.
- */
-fast_exc_return_irq: /* restores irq state too */
- ld r3,SOFTE(r1)
- TRACE_AND_RESTORE_IRQ(r3);
- ld r12,_MSR(r1)
- rldicl r4,r12,49,63 /* get MSR_EE to LSB */
- stb r4,PACAHARDIRQEN(r13) /* restore paca->hard_enabled */
- b 1f
-
- .globl fast_exception_return
-fast_exception_return:
- ld r12,_MSR(r1)
-1: ld r11,_NIP(r1)
- andi. r3,r12,MSR_RI /* check if RI is set */
- beq- unrecov_fer
-
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING
- andi. r3,r12,MSR_PR
- beq 2f
- ACCOUNT_CPU_USER_EXIT(r3, r4)
-2:
-#endif
-
- ld r3,_CCR(r1)
- ld r4,_LINK(r1)
- ld r5,_CTR(r1)
- ld r6,_XER(r1)
- mtcr r3
- mtlr r4
- mtctr r5
- mtxer r6
- REST_GPR(0, r1)
- REST_8GPRS(2, r1)
-
- ld r10,PACAKMSR(r13)
- clrrdi r10,r10,2 /* clear RI */
- mtmsrd r10,1
-
- mtspr SPRN_SRR1,r12
- mtspr SPRN_SRR0,r11
- REST_4GPRS(10, r1)
- ld r1,GPR1(r1)
- rfid
- b . /* prevent speculative execution */
-
-unrecov_fer:
- bl .save_nvgprs
-1: addi r3,r1,STACK_FRAME_OVERHEAD
- bl .unrecoverable_exception
- b 1b
-
-
-/*
* Hash table stuff
*/
.align 7
@@ -905,19 +874,16 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_SLB)
* r4 contains the required access permissions
* r5 contains the trap number
*
- * at return r3 = 0 for success
+ * at return r3 = 0 for success, 1 for page fault, negative for error
*/
bl .hash_page /* build HPTE if possible */
cmpdi r3,0 /* see if hash_page succeeded */
- /*
- * Here we have interrupts hard-disabled, so it is sufficient
- * to restore paca->{soft,hard}_enable and get out.
- */
+ /* Success */
beq fast_exc_return_irq /* Return from exception on success */
- /* For a hash failure, we don't bother re-enabling interrupts */
- ble- 13f
+ /* Error */
+ blt- 13f
/* Here we have a page fault that hash_page can't handle. */
handle_page_fault:
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 40759fbfb171..58bddee8e1e8 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -38,6 +38,7 @@
#include <asm/irqflags.h>
#include <asm/kvm_book3s_asm.h>
#include <asm/ptrace.h>
+#include <asm/hw_irq.h>
/* The physical memory is laid out such that the secondary processor
* spin code sits at 0x0000...0x00ff. On server, the vectors follow
@@ -550,7 +551,8 @@ _GLOBAL(pmac_secondary_start)
*/
li r0,0
stb r0,PACASOFTIRQEN(r13)
- stb r0,PACAHARDIRQEN(r13)
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
/* Create a temp kernel stack for use before relocation is on. */
ld r1,PACAEMERGSP(r13)
@@ -601,9 +603,12 @@ __secondary_start:
li r7,0
mtlr r7
- /* Mark interrupts both hard and soft disabled */
- stb r7,PACAHARDIRQEN(r13)
+ /* Mark interrupts soft and hard disabled (they might be enabled
+ * in the PACA when doing hotplug)
+ */
stb r7,PACASOFTIRQEN(r13)
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
/* enable MMU and jump to start_secondary */
LOAD_REG_ADDR(r3, .start_secondary_prolog)
@@ -750,13 +755,18 @@ _INIT_GLOBAL(start_here_common)
/* Load the TOC (virtual address) */
ld r2,PACATOC(r13)
+ /* Do more system initializations in virtual mode */
bl .setup_system
- /* Load up the kernel context */
-5: li r5,0
- stb r5,PACASOFTIRQEN(r13) /* Soft Disabled */
- stb r5,PACAHARDIRQEN(r13) /* Hard Disabled on others */
+ /* Mark interrupts soft and hard disabled (they might be enabled
+ * in the PACA when doing hotplug)
+ */
+ li r0,0
+ stb r0,PACASOFTIRQEN(r13)
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
+ /* Generic kernel entry */
bl .start_kernel
/* Not reached */
diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c
index 0a48bf5db6c8..8f7a2b62863d 100644
--- a/arch/powerpc/kernel/idle.c
+++ b/arch/powerpc/kernel/idle.c
@@ -84,7 +84,11 @@ void cpu_idle(void)
start_critical_timings();
- local_irq_enable();
+ /* Some power_save functions return with
+ * interrupts enabled, some don't.
+ */
+ if (irqs_disabled())
+ local_irq_enable();
set_thread_flag(TIF_POLLING_NRFLAG);
} else {
diff --git a/arch/powerpc/kernel/idle_book3e.S b/arch/powerpc/kernel/idle_book3e.S
index 16c002d6bdf1..ff007b59448d 100644
--- a/arch/powerpc/kernel/idle_book3e.S
+++ b/arch/powerpc/kernel/idle_book3e.S
@@ -29,43 +29,30 @@ _GLOBAL(book3e_idle)
wrteei 0
/* Now check if an interrupt came in while we were soft disabled
- * since we may otherwise lose it (doorbells etc...). We know
- * that since PACAHARDIRQEN will have been cleared in that case.
+ * since we may otherwise lose it (doorbells etc...).
*/
- lbz r3,PACAHARDIRQEN(r13)
+ lbz r3,PACAIRQHAPPENED(r13)
cmpwi cr0,r3,0
- beqlr
+ bnelr
- /* Now we are going to mark ourselves as soft and hard enables in
+ /* Now we are going to mark ourselves as soft and hard enabled in
* order to be able to take interrupts while asleep. We inform lockdep
* of that. We don't actually turn interrupts on just yet tho.
*/
#ifdef CONFIG_TRACE_IRQFLAGS
stdu r1,-128(r1)
bl .trace_hardirqs_on
+ addi r1,r1,128
#endif
li r0,1
stb r0,PACASOFTIRQEN(r13)
- stb r0,PACAHARDIRQEN(r13)
/* Interrupts will make use return to LR, so get something we want
* in there
*/
bl 1f
- /* Hard disable interrupts again */
- wrteei 0
-
- /* Mark them off again in the PACA as well */
- li r0,0
- stb r0,PACASOFTIRQEN(r13)
- stb r0,PACAHARDIRQEN(r13)
-
- /* Tell lockdep about it */
-#ifdef CONFIG_TRACE_IRQFLAGS
- bl .trace_hardirqs_off
- addi r1,r1,128
-#endif
+ /* And return (interrupts are on) */
ld r0,16(r1)
mtlr r0
blr
diff --git a/arch/powerpc/kernel/idle_power4.S b/arch/powerpc/kernel/idle_power4.S
index ba3195478600..d8cdba4c28b2 100644
--- a/arch/powerpc/kernel/idle_power4.S
+++ b/arch/powerpc/kernel/idle_power4.S
@@ -14,6 +14,7 @@
#include <asm/thread_info.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
+#include <asm/irqflags.h>
#undef DEBUG
@@ -29,14 +30,31 @@ END_FTR_SECTION_IFCLR(CPU_FTR_CAN_NAP)
cmpwi 0,r4,0
beqlr
- /* Go to NAP now */
+ /* Hard disable interrupts */
mfmsr r7
rldicl r0,r7,48,1
rotldi r0,r0,16
- mtmsrd r0,1 /* hard-disable interrupts */
+ mtmsrd r0,1
+
+ /* Check if something happened while soft-disabled */
+ lbz r0,PACAIRQHAPPENED(r13)
+ cmpwi cr0,r0,0
+ bnelr
+
+ /* Soft-enable interrupts */
+#ifdef CONFIG_TRACE_IRQFLAGS
+ mflr r0
+ std r0,16(r1)
+ stdu r1,-128(r1)
+ bl .trace_hardirqs_on
+ addi r1,r1,128
+ ld r0,16(r1)
+ mtlr r0
+#endif /* CONFIG_TRACE_IRQFLAGS */
+
+ TRACE_ENABLE_INTS
li r0,1
stb r0,PACASOFTIRQEN(r13) /* we'll hard-enable shortly */
- stb r0,PACAHARDIRQEN(r13)
BEGIN_FTR_SECTION
DSSALL
sync
diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/idle_power7.S
index fcdff198da4b..0cdc9a392839 100644
--- a/arch/powerpc/kernel/idle_power7.S
+++ b/arch/powerpc/kernel/idle_power7.S
@@ -1,5 +1,5 @@
/*
- * This file contains the power_save function for 970-family CPUs.
+ * This file contains the power_save function for Power7 CPUs.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -15,6 +15,7 @@
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/ppc-opcode.h>
+#include <asm/hw_irq.h>
#undef DEBUG
@@ -51,9 +52,25 @@ _GLOBAL(power7_idle)
rldicl r9,r9,48,1
rotldi r9,r9,16
mtmsrd r9,1 /* hard-disable interrupts */
+
+ /* Check if something happened while soft-disabled */
+ lbz r0,PACAIRQHAPPENED(r13)
+ cmpwi cr0,r0,0
+ beq 1f
+ addi r1,r1,INT_FRAME_SIZE
+ ld r0,16(r1)
+ mtlr r0
+ blr
+
+1: /* We mark irqs hard disabled as this is the state we'll
+ * be in when returning and we need to tell arch_local_irq_restore()
+ * about it
+ */
+ li r0,PACA_IRQ_HARD_DIS
+ stb r0,PACAIRQHAPPENED(r13)
+
+ /* We haven't lost state ... yet */
li r0,0
- stb r0,PACASOFTIRQEN(r13) /* we'll hard-enable shortly */
- stb r0,PACAHARDIRQEN(r13)
stb r0,PACA_NAPSTATELOST(r13)
/* Continue saving state */
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 9b6e80668cfb..eb804e15b29b 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -95,14 +95,14 @@ extern int tau_interrupts(int);
int distribute_irqs = 1;
-static inline notrace unsigned long get_hard_enabled(void)
+static inline notrace unsigned long get_irq_happened(void)
{
- unsigned long enabled;
+ unsigned long happened;
__asm__ __volatile__("lbz %0,%1(13)"
- : "=r" (enabled) : "i" (offsetof(struct paca_struct, hard_enabled)));
+ : "=r" (happened) : "i" (offsetof(struct paca_struct, irq_happened)));
- return enabled;
+ return happened;
}
static inline notrace void set_soft_enabled(unsigned long enable)
@@ -111,88 +111,167 @@ static inline notrace void set_soft_enabled(unsigned long enable)
: : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
}
-static inline notrace void decrementer_check_overflow(void)
+static inline notrace int decrementer_check_overflow(void)
{
- u64 now = get_tb_or_rtc();
- u64 *next_tb;
-
- preempt_disable();
- next_tb = &__get_cpu_var(decrementers_next_tb);
-
+ u64 now = get_tb_or_rtc();
+ u64 *next_tb = &__get_cpu_var(decrementers_next_tb);
+
if (now >= *next_tb)
set_dec(1);
- preempt_enable();
+ return now >= *next_tb;
}
-notrace void arch_local_irq_restore(unsigned long en)
+/* This is called whenever we are re-enabling interrupts
+ * and returns either 0 (nothing to do) or 500/900 if there's
+ * either an EE or a DEC to generate.
+ *
+ * This is called in two contexts: From arch_local_irq_restore()
+ * before soft-enabling interrupts, and from the exception exit
+ * path when returning from an interrupt from a soft-disabled to
+ * a soft enabled context. In both case we have interrupts hard
+ * disabled.
+ *
+ * We take care of only clearing the bits we handled in the
+ * PACA irq_happened field since we can only re-emit one at a
+ * time and we don't want to "lose" one.
+ */
+notrace unsigned int __check_irq_replay(void)
{
/*
- * get_paca()->soft_enabled = en;
- * Is it ever valid to use local_irq_restore(0) when soft_enabled is 1?
- * That was allowed before, and in such a case we do need to take care
- * that gcc will set soft_enabled directly via r13, not choose to use
- * an intermediate register, lest we're preempted to a different cpu.
+ * We use local_paca rather than get_paca() to avoid all
+ * the debug_smp_processor_id() business in this low level
+ * function
*/
- set_soft_enabled(en);
- if (!en)
- return;
+ unsigned char happened = local_paca->irq_happened;
-#ifdef CONFIG_PPC_STD_MMU_64
- if (firmware_has_feature(FW_FEATURE_ISERIES)) {
- /*
- * Do we need to disable preemption here? Not really: in the
- * unlikely event that we're preempted to a different cpu in
- * between getting r13, loading its lppaca_ptr, and loading
- * its any_int, we might call iseries_handle_interrupts without
- * an interrupt pending on the new cpu, but that's no disaster,
- * is it? And the business of preempting us off the old cpu
- * would itself involve a local_irq_restore which handles the
- * interrupt to that cpu.
- *
- * But use "local_paca->lppaca_ptr" instead of "get_lppaca()"
- * to avoid any preemption checking added into get_paca().
- */
- if (local_paca->lppaca_ptr->int_dword.any_int)
- iseries_handle_interrupts();
+ /* Clear bit 0 which we wouldn't clear otherwise */
+ local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS;
+
+ /*
+ * Force the delivery of pending soft-disabled interrupts on PS3.
+ * Any HV call will have this side effect.
+ */
+ if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
+ u64 tmp, tmp2;
+ lv1_get_version_info(&tmp, &tmp2);
}
-#endif /* CONFIG_PPC_STD_MMU_64 */
/*
- * if (get_paca()->hard_enabled) return;
- * But again we need to take care that gcc gets hard_enabled directly
- * via r13, not choose to use an intermediate register, lest we're
- * preempted to a different cpu in between the two instructions.
+ * We may have missed a decrementer interrupt. We check the
+ * decrementer itself rather than the paca irq_happened field
+ * in case we also had a rollover while hard disabled
+ */
+ local_paca->irq_happened &= ~PACA_IRQ_DEC;
+ if (decrementer_check_overflow())
+ return 0x900;
+
+ /* Finally check if an external interrupt happened */
+ local_paca->irq_happened &= ~PACA_IRQ_EE;
+ if (happened & PACA_IRQ_EE)
+ return 0x500;
+
+#ifdef CONFIG_PPC_BOOK3E
+ /* Finally check if an EPR external interrupt happened
+ * this bit is typically set if we need to handle another
+ * "edge" interrupt from within the MPIC "EPR" handler
+ */
+ local_paca->irq_happened &= ~PACA_IRQ_EE_EDGE;
+ if (happened & PACA_IRQ_EE_EDGE)
+ return 0x500;
+
+ local_paca->irq_happened &= ~PACA_IRQ_DBELL;
+ if (happened & PACA_IRQ_DBELL)
+ return 0x280;
+#endif /* CONFIG_PPC_BOOK3E */
+
+ /* There should be nothing left ! */
+ BUG_ON(local_paca->irq_happened != 0);
+
+ return 0;
+}
+
+notrace void arch_local_irq_restore(unsigned long en)
+{
+ unsigned char irq_happened;
+ unsigned int replay;
+
+ /* Write the new soft-enabled value */
+ set_soft_enabled(en);
+ if (!en)
+ return;
+ /*
+ * From this point onward, we can take interrupts, preempt,
+ * etc... unless we got hard-disabled. We check if an event
+ * happened. If none happened, we know we can just return.
+ *
+ * We may have preempted before the check below, in which case
+ * we are checking the "new" CPU instead of the old one. This
+ * is only a problem if an event happened on the "old" CPU.
+ *
+ * External interrupt events on non-iseries will have caused
+ * interrupts to be hard-disabled, so there is no problem, we
+ * cannot have preempted.
+ *
+ * That leaves us with EEs on iSeries or decrementer interrupts,
+ * which I decided to safely ignore. The preemption would have
+ * itself been the result of an interrupt, upon which return we
+ * will have checked for pending events on the old CPU.
*/
- if (get_hard_enabled())
+ irq_happened = get_irq_happened();
+ if (!irq_happened)
return;
/*
- * Need to hard-enable interrupts here. Since currently disabled,
- * no need to take further asm precautions against preemption; but
- * use local_paca instead of get_paca() to avoid preemption checking.
+ * We need to hard disable to get a trusted value from
+ * __check_irq_replay(). We also need to soft-disable
+ * again to avoid warnings in there due to the use of
+ * per-cpu variables.
+ *
+ * We know that if the value in irq_happened is exactly 0x01
+ * then we are already hard disabled (there are other less
+ * common cases that we'll ignore for now), so we skip the
+ * (expensive) mtmsrd.
*/
- local_paca->hard_enabled = en;
+ if (unlikely(irq_happened != PACA_IRQ_HARD_DIS))
+ __hard_irq_disable();
+ set_soft_enabled(0);
/*
- * Trigger the decrementer if we have a pending event. Some processors
- * only trigger on edge transitions of the sign bit. We might also
- * have disabled interrupts long enough that the decrementer wrapped
- * to positive.
+ * Check if anything needs to be re-emitted. We haven't
+ * soft-enabled yet to avoid warnings in decrementer_check_overflow
+ * accessing per-cpu variables
*/
- decrementer_check_overflow();
+ replay = __check_irq_replay();
+
+ /* We can soft-enable now */
+ set_soft_enabled(1);
/*
- * Force the delivery of pending soft-disabled interrupts on PS3.
- * Any HV call will have this side effect.
+ * And replay if we have to. This will return with interrupts
+ * hard-enabled.
*/
- if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
- u64 tmp, tmp2;
- lv1_get_version_info(&tmp, &tmp2);
+ if (replay) {
+ __replay_interrupt(replay);
+ return;
}
+ /* Finally, let's ensure we are hard enabled */
__hard_irq_enable();
}
EXPORT_SYMBOL(arch_local_irq_restore);
+
+/*
+ * This is specifically called by assembly code to re-enable interrupts
+ * if they are currently disabled. This is typically called before
+ * schedule() or do_signal() when returning to userspace. We do it
+ * in C to avoid the burden of dealing with lockdep etc...
+ */
+void restore_interrupts(void)
+{
+ if (irqs_disabled())
+ local_irq_enable();
+}
+
#endif /* CONFIG_PPC64 */
int arch_show_interrupts(struct seq_file *p, int prec)
@@ -360,8 +439,17 @@ void do_IRQ(struct pt_regs *regs)
check_stack_overflow();
+ /*
+ * Query the platform PIC for the interrupt & ack it.
+ *
+ * This will typically lower the interrupt line to the CPU
+ */
irq = ppc_md.get_irq();
+ /* We can hard enable interrupts now */
+ may_hard_irq_enable();
+
+ /* And finally process it */
if (irq != NO_IRQ && irq != NO_IRQ_IGNORE)
handle_one_irq(irq);
else if (irq != NO_IRQ_IGNORE)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index bf80a1d5f8fe..e40707032ac3 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -647,6 +647,9 @@ void show_regs(struct pt_regs * regs)
printk("MSR: "REG" ", regs->msr);
printbits(regs->msr, msr_bits);
printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer);
+#ifdef CONFIG_PPC64
+ printk("SOFTE: %ld\n", regs->softe);
+#endif
trap = TRAP(regs);
if ((regs->trap != 0xc00) && cpu_has_feature(CPU_FTR_CFAR))
printk("CFAR: "REG"\n", regs->orig_gpr3);
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 567dd7c3ac2a..f81c81b92f0e 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -259,7 +259,6 @@ void accumulate_stolen_time(void)
u64 sst, ust;
u8 save_soft_enabled = local_paca->soft_enabled;
- u8 save_hard_enabled = local_paca->hard_enabled;
/* We are called early in the exception entry, before
* soft/hard_enabled are sync'ed to the expected state
@@ -268,7 +267,6 @@ void accumulate_stolen_time(void)
* complain
*/
local_paca->soft_enabled = 0;
- local_paca->hard_enabled = 0;
sst = scan_dispatch_log(local_paca->starttime_user);
ust = scan_dispatch_log(local_paca->starttime);
@@ -277,7 +275,6 @@ void accumulate_stolen_time(void)
local_paca->stolen_time += ust + sst;
local_paca->soft_enabled = save_soft_enabled;
- local_paca->hard_enabled = save_hard_enabled;
}
static inline u64 calculate_stolen_time(u64 stop_tb)
@@ -580,6 +577,11 @@ void timer_interrupt(struct pt_regs * regs)
if (!cpu_online(smp_processor_id()))
return;
+ /* Conditionally hard-enable interrupts now that the DEC has been
+ * bumped to its maximum value
+ */
+ may_hard_irq_enable();
+
trace_timer_interrupt_entry(regs);
__get_cpu_var(irq_stat).timer_irqs++;
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-24 20:41:36 +0000