[PATCH 00/10] powerpc/booke64: critical and mcheck support

[PATCH 00/10] powerpc/booke64: critical and mcheck support

[Scott Wood]

This patchset adds the state saving required to safely take
critical and machine check exceptions on 64-bit booke, including
TLB misses from inside such exceptions.  Previously, the kernel simply
hung when encountering such an exception.

Scott Wood (8):
  powerpc/booke64: Fix exception numbers
  powerpc/e6500: Make TLB lock recursive
  powerpc/booke64: Use SPRG7 for VDSO
  powerpc/booke64: Use SPRG_TLB_EXFRAME on bolted handlers
  powerpc/booke64: Remove ints from EXCEPTION_COMMON
  powerpc/booke64: Add crit/mc/debug support to EXCEPTION_COMMON
  powerpc/booke64: Critical and machine check exception support
  Revert "powerpc/watchdog: Don't enable interrupt on PPC64 BookE"

Tiejun Chen (2):
  powerpc/book3e: initialize crit/mc/dbg kernel stack pointers
  powerpc/book3e: store crit/mc/dbg exception thread info

 arch/powerpc/include/asm/exception-64e.h    |  15 +-
 arch/powerpc/include/asm/kvm_booke_hv_asm.h |  17 +-
 arch/powerpc/include/asm/mmu-book3e.h       |   9 +-
 arch/powerpc/include/asm/paca.h             |   9 +-
 arch/powerpc/include/asm/reg.h              |  13 +-
 arch/powerpc/kernel/asm-offsets.c           |   2 +-
 arch/powerpc/kernel/exceptions-64e.S        | 435 +++++++++++++++++++++-------
 arch/powerpc/kernel/setup_64.c              |  20 +-
 arch/powerpc/kernel/vdso.c                  |   8 +-
 arch/powerpc/kernel/vdso32/getcpu.S         |   2 +-
 arch/powerpc/kernel/vdso64/getcpu.S         |   2 +-
 arch/powerpc/kvm/book3s_hv_rmhandlers.S     |   4 +-
 arch/powerpc/kvm/book3s_interrupts.S        |   4 +-
 arch/powerpc/kvm/bookehv_interrupts.S       |  24 +-
 arch/powerpc/mm/tlb_low_64e.S               |  63 ++--
 arch/powerpc/mm/tlb_nohash.c                |  11 +
 drivers/watchdog/booke_wdt.c                |   8 -
 17 files changed, 461 insertions(+), 185 deletions(-)

-- 
1.8.3.2

[PATCH 01/10] powerpc/book3e: initialize crit/mc/dbg kernel stack pointers

[Scott Wood]

From: Tiejun Chen <tiejun.chen@windriver.com>

We already allocated critical/machine/debug check exceptions, but
we also should initialize those associated kernel stack pointers
for use by special exceptions in the PACA.

Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
---
 arch/powerpc/kernel/setup_64.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index f5f11a7..da9c42f 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -552,14 +552,20 @@ static void __init irqstack_early_init(void)
 static void __init exc_lvl_early_init(void)
 {
 	unsigned int i;
+	unsigned long sp;
 
 	for_each_possible_cpu(i) {
-		critirq_ctx[i] = (struct thread_info *)
-			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
-		dbgirq_ctx[i] = (struct thread_info *)
-			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
-		mcheckirq_ctx[i] = (struct thread_info *)
-			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
+		sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
+		critirq_ctx[i] = (struct thread_info *)__va(sp);
+		paca[i].crit_kstack = __va(sp + THREAD_SIZE);
+
+		sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
+		dbgirq_ctx[i] = (struct thread_info *)__va(sp);
+		paca[i].dbg_kstack = __va(sp + THREAD_SIZE);
+
+		sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
+		mcheckirq_ctx[i] = (struct thread_info *)__va(sp);
+		paca[i].mc_kstack = __va(sp + THREAD_SIZE);
 	}
 
 	if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
-- 
1.8.3.2

[PATCH 02/10] powerpc/book3e: store crit/mc/dbg exception thread info

[Scott Wood]

From: Tiejun Chen <tiejun.chen@windriver.com>

We need to store thread info to these exception thread info like something
we already did for PPC32.

Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
---
 arch/powerpc/kernel/exceptions-64e.S | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 063b65d..6772512 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -36,6 +36,19 @@
  */
 #define	SPECIAL_EXC_FRAME_SIZE	INT_FRAME_SIZE
 
+/* 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);
+
+
 /* Exception prolog code for all exceptions */
 #define EXCEPTION_PROLOG(n, intnum, type, addition)	    		    \
 	mtspr	SPRN_SPRG_##type##_SCRATCH,r13;	/* get spare registers */   \
@@ -69,19 +82,22 @@
 
 #define CRIT_SET_KSTACK						            \
 	ld	r1,PACA_CRIT_STACK(r13);				    \
-	subi	r1,r1,SPECIAL_EXC_FRAME_SIZE;
+	subi	r1,r1,SPECIAL_EXC_FRAME_SIZE;				    \
+	EXC_LEVEL_EXCEPTION_PROLOG(CRIT);
 #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;
+	subi	r1,r1,SPECIAL_EXC_FRAME_SIZE;				    \
+	EXC_LEVEL_EXCEPTION_PROLOG(DBG);
 #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;
+	subi	r1,r1,SPECIAL_EXC_FRAME_SIZE;				    \
+	EXC_LEVEL_EXCEPTION_PROLOG(MC);
 #define SPRN_MC_SRR0	SPRN_MCSRR0
 #define SPRN_MC_SRR1	SPRN_MCSRR1
 
-- 
1.8.3.2

[PATCH 03/10] powerpc/booke64: Fix exception numbers

[Scott Wood]

altivec_unavailable was commented as 0xf20 but the code uses 0x200.
Note that 0xf20 is also used by ap_unavailable.

altivec_assist was commented as 0x1700 but the code uses 0x220.

critical_input was commented as 0x580 but the code uses 0x100.

machine_check was commented and implemented as 0x200, which conflicts
with altivec_assist (it only builds because MC_EXCEPTION_PROLOG is
commented out).  Changed to the fixed IVOR value of 0x000.

Signed-off-by: Scott Wood <scottwood@freescale.com>
---
 arch/powerpc/kernel/exceptions-64e.S | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 6772512..41380a4 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -299,8 +299,8 @@ exception_marker:
 	.balign	0x1000
 	.globl interrupt_base_book3e
 interrupt_base_book3e:					/* fake trap */
-	EXCEPTION_STUB(0x000, machine_check)		/* 0x0200 */
-	EXCEPTION_STUB(0x020, critical_input)		/* 0x0580 */
+	EXCEPTION_STUB(0x000, machine_check)
+	EXCEPTION_STUB(0x020, critical_input)		/* 0x0100 */
 	EXCEPTION_STUB(0x040, debug_crit)		/* 0x0d00 */
 	EXCEPTION_STUB(0x060, data_storage)		/* 0x0300 */
 	EXCEPTION_STUB(0x080, instruction_storage)	/* 0x0400 */
@@ -315,8 +315,8 @@ interrupt_base_book3e:					/* fake trap */
 	EXCEPTION_STUB(0x1a0, watchdog)			/* 0x09f0 */
 	EXCEPTION_STUB(0x1c0, data_tlb_miss)
 	EXCEPTION_STUB(0x1e0, instruction_tlb_miss)
-	EXCEPTION_STUB(0x200, altivec_unavailable)	/* 0x0f20 */
-	EXCEPTION_STUB(0x220, altivec_assist)		/* 0x1700 */
+	EXCEPTION_STUB(0x200, altivec_unavailable)
+	EXCEPTION_STUB(0x220, altivec_assist)
 	EXCEPTION_STUB(0x260, perfmon)
 	EXCEPTION_STUB(0x280, doorbell)
 	EXCEPTION_STUB(0x2a0, doorbell_crit)
@@ -343,9 +343,9 @@ interrupt_end_book3e:
 
 /* Machine Check Interrupt */
 	START_EXCEPTION(machine_check);
-	MC_EXCEPTION_PROLOG(0x200, BOOKE_INTERRUPT_MACHINE_CHECK,
+	MC_EXCEPTION_PROLOG(0x000, BOOKE_INTERRUPT_MACHINE_CHECK,
 			    PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x200, PACA_EXMC, INTS_DISABLE)
+//	EXCEPTION_COMMON(0x000, PACA_EXMC, INTS_DISABLE)
 //	bl	special_reg_save_mc
 //	addi	r3,r1,STACK_FRAME_OVERHEAD
 //	CHECK_NAPPING();
-- 
1.8.3.2

[PATCH 04/10] powerpc/e6500: Make TLB lock recursive

[Scott Wood]

Once special level interrupts are supported, we may take nested TLB
misses -- so allow the same thread to acquire the lock recursively.

The lock will not be effective against the nested TLB miss handler
trying to write the same entry as the interrupted TLB miss handler, but
that's also a problem on non-threaded CPUs that lack TLB write
conditional.  This will be addressed in the patch that enables crit/mc
support by invalidating the TLB on return from level exceptions.

Signed-off-by: Scott Wood <scottwood@freescale.com>
---
 arch/powerpc/include/asm/mmu-book3e.h |  9 ++++++---
 arch/powerpc/kernel/setup_64.c        |  2 ++
 arch/powerpc/mm/tlb_low_64e.S         | 19 ++++++++++++-------
 3 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/include/asm/mmu-book3e.h b/arch/powerpc/include/asm/mmu-book3e.h
index 89b785d..901dac6 100644
--- a/arch/powerpc/include/asm/mmu-book3e.h
+++ b/arch/powerpc/include/asm/mmu-book3e.h
@@ -287,11 +287,14 @@ extern int mmu_linear_psize;
 extern int mmu_vmemmap_psize;
 
 struct tlb_core_data {
+	/*
+	 * Per-core spinlock for e6500 TLB handlers (no tlbsrx.)
+	 * Must be the first struct element.
+	 */
+	u8 lock;
+
 	/* For software way selection, as on Freescale TLB1 */
 	u8 esel_next, esel_max, esel_first;
-
-	/* Per-core spinlock for e6500 TLB handlers (no tlbsrx.) */
-	u8 lock;
 };
 
 #ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index da9c42f..4933909 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -102,6 +102,8 @@ static void setup_tlb_core_data(void)
 {
 	int cpu;
 
+	BUILD_BUG_ON(offsetof(struct tlb_core_data, lock) != 0);
+
 	for_each_possible_cpu(cpu) {
 		int first = cpu_first_thread_sibling(cpu);
 
diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S
index 6bf5050..1e50249 100644
--- a/arch/powerpc/mm/tlb_low_64e.S
+++ b/arch/powerpc/mm/tlb_low_64e.S
@@ -284,7 +284,7 @@ itlb_miss_fault_bolted:
  * r14 = page table base
  * r13 = PACA
  * r11 = tlb_per_core ptr
- * r10 = crap (free to use)
+ * r10 = cpu number
  */
 tlb_miss_common_e6500:
 	/*
@@ -293,15 +293,18 @@ tlb_miss_common_e6500:
 	 *
 	 * MAS6:IND should be already set based on MAS4
 	 */
-	addi	r10,r11,TCD_LOCK
-1:	lbarx	r15,0,r10
+1:	lbarx	r15,0,r11
+	lhz	r10,PACAPACAINDEX(r13)
 	cmpdi	r15,0
+	cmpdi	cr1,r15,1	/* set cr1.eq = 0 for non-recursive */
 	bne	2f
-	li	r15,1
-	stbcx.	r15,0,r10
+	stbcx.	r10,0,r11
 	bne	1b
+3:
 	.subsection 1
-2:	lbz	r15,0(r10)
+2:	cmpd	cr1,r15,r10	/* recursive lock due to mcheck/crit/etc? */
+	beq	cr1,3b		/* unlock will happen if cr1.eq = 0 */
+	lbz	r15,0(r11)
 	cmpdi	r15,0
 	bne	2b
 	b	1b
@@ -379,9 +382,11 @@ tlb_miss_common_e6500:
 
 tlb_miss_done_e6500:
 	.macro	tlb_unlock_e6500
+	beq	cr1,1f		/* no unlock if lock was recursively grabbed */
 	li	r15,0
 	isync
-	stb	r15,TCD_LOCK(r11)
+	stb	r15,0(r11)
+1:
 	.endm
 
 	tlb_unlock_e6500
-- 
1.8.3.2

[PATCH 05/10] powerpc/booke64: Use SPRG7 for VDSO

[Scott Wood]

Previously SPRG3 was marked for use by both VDSO and critical
interrupts (though critical interrupts were not fully implemented).

In commit 8b64a9dfb091f1eca8b7e58da82f1e7d1d5fe0ad ("powerpc/booke64:
Use SPRG0/3 scratch for bolted TLB miss & crit int"), Mihai Caraman
made an attempt to resolve this conflict by restoring the VDSO value
early in the critical interrupt, but this has some issues:

 - It's incompatible with EXCEPTION_COMMON which restores r13 from the
   by-then-overwritten scratch (this cost me some debugging time).
 - It forces critical exceptions to be a special case handled
   differently from even machine check and debug level exceptions.
 - It didn't occur to me that it was possible to make this work at all
   (by doing a final "ld r13, PACA_EXCRIT+EX_R13(r13)") until after
   I made (most of) this patch. :-)

It might be worth investigating using a load rather than SPRG on return
from all exceptions (except TLB misses where the scratch never leaves
the SPRG) -- it could save a few cycles.  Until then, let's stick with
SPRG for all exceptions.

Since we cannot use SPRG4-7 for scratch without corrupting the state of
a KVM guest, move VDSO to SPRG7 on book3e.  Since neither SPRG4-7 nor
critical interrupts exist on book3s, SPRG3 is still used for VDSO
there.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: kvm-ppc@vger.kernel.org
---
 arch/powerpc/include/asm/exception-64e.h    |  5 ++---
 arch/powerpc/include/asm/kvm_booke_hv_asm.h |  9 +--------
 arch/powerpc/include/asm/paca.h             |  2 +-
 arch/powerpc/include/asm/reg.h              | 13 ++++++++++---
 arch/powerpc/kernel/asm-offsets.c           |  2 +-
 arch/powerpc/kernel/exceptions-64e.S        | 19 ++-----------------
 arch/powerpc/kernel/vdso.c                  |  8 ++++----
 arch/powerpc/kernel/vdso32/getcpu.S         |  2 +-
 arch/powerpc/kernel/vdso64/getcpu.S         |  2 +-
 arch/powerpc/kvm/book3s_hv_rmhandlers.S     |  4 ++--
 arch/powerpc/kvm/book3s_interrupts.S        |  4 ++--
 arch/powerpc/kvm/bookehv_interrupts.S       | 10 ++++++----
 12 files changed, 33 insertions(+), 47 deletions(-)

diff --git a/arch/powerpc/include/asm/exception-64e.h b/arch/powerpc/include/asm/exception-64e.h
index 51fa43e..e73452f 100644
--- a/arch/powerpc/include/asm/exception-64e.h
+++ b/arch/powerpc/include/asm/exception-64e.h
@@ -46,9 +46,8 @@
 #define EX_CR		(1 * 8)
 #define EX_R10		(2 * 8)
 #define EX_R11		(3 * 8)
-#define EX_R13		(4 * 8)
-#define EX_R14		(5 * 8)
-#define EX_R15		(6 * 8)
+#define EX_R14		(4 * 8)
+#define EX_R15		(5 * 8)
 
 /*
  * The TLB miss exception uses different slots.
diff --git a/arch/powerpc/include/asm/kvm_booke_hv_asm.h b/arch/powerpc/include/asm/kvm_booke_hv_asm.h
index 3a79f53..c3e3fd5 100644
--- a/arch/powerpc/include/asm/kvm_booke_hv_asm.h
+++ b/arch/powerpc/include/asm/kvm_booke_hv_asm.h
@@ -36,20 +36,13 @@
  *   *(r8 + GPR11) = saved r11
  *
  * 64-bit host
- * Expected inputs (GEN/GDBELL/DBG/MC exception types):
+ * Expected inputs (GEN/GDBELL/DBG/CRIT/MC exception types):
  *  r10 = saved CR
  *  r13 = PACA_POINTER
  *  *(r13 + PACA_EX##type + EX_R10) = saved r10
  *  *(r13 + PACA_EX##type + EX_R11) = saved r11
  *  SPRN_SPRG_##type##_SCRATCH = saved r13
  *
-  * Expected inputs (CRIT exception type):
- *  r10 = saved CR
- *  r13 = PACA_POINTER
- *  *(r13 + PACA_EX##type + EX_R10) = saved r10
- *  *(r13 + PACA_EX##type + EX_R11) = saved r11
- *  *(r13 + PACA_EX##type + EX_R13) = saved r13
- *
  * Expected inputs (TLB exception type):
  *  r10 = saved CR
  *  r13 = PACA_POINTER
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 9c5dbc3..948f01a 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -146,7 +146,7 @@ struct paca_struct {
 	u8 io_sync;			/* writel() needs spin_unlock sync */
 	u8 irq_work_pending;		/* IRQ_WORK interrupt while soft-disable */
 	u8 nap_state_lost;		/* NV GPR values lost in power7_idle */
-	u64 sprg3;			/* Saved user-visible sprg */
+	u64 sprg_vdso;			/* Saved user-visible sprg */
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	u64 tm_scratch;                 /* TM scratch area for reclaim */
 #endif
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 90c06ec..b9ac329 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -577,9 +577,13 @@
 #define SPRN_SPRG3	0x113	/* Special Purpose Register General 3 */
 #define SPRN_USPRG3	0x103	/* SPRG3 userspace read */
 #define SPRN_SPRG4	0x114	/* Special Purpose Register General 4 */
+#define SPRN_USPRG4	0x104	/* SPRG4 userspace read */
 #define SPRN_SPRG5	0x115	/* Special Purpose Register General 5 */
+#define SPRN_USPRG5	0x105	/* SPRG5 userspace read */
 #define SPRN_SPRG6	0x116	/* Special Purpose Register General 6 */
+#define SPRN_USPRG6	0x106	/* SPRG6 userspace read */
 #define SPRN_SPRG7	0x117	/* Special Purpose Register General 7 */
+#define SPRN_USPRG7	0x107	/* SPRG7 userspace read */
 #define SPRN_SRR0	0x01A	/* Save/Restore Register 0 */
 #define SPRN_SRR1	0x01B	/* Save/Restore Register 1 */
 #define   SRR1_ISI_NOPT		0x40000000 /* ISI: Not found in hash */
@@ -879,11 +883,10 @@
  * 64-bit embedded
  *	- SPRG0 generic exception scratch
  *	- SPRG2 TLB exception stack
- *	- SPRG3 critical exception scratch and
- *        CPU and NUMA node for VDSO getcpu (user visible)
+ *	- SPRG3 critical exception scratch (user visible, sorry!)
  *	- SPRG4 unused (user visible)
  *	- SPRG6 TLB miss scratch (user visible, sorry !)
- *	- SPRG7 critical exception scratch
+ *	- SPRG7 CPU and NUMA node for VDSO getcpu (user visible)
  *	- SPRG8 machine check exception scratch
  *	- SPRG9 debug exception scratch
  *
@@ -940,6 +943,8 @@
 #define SPRN_SPRG_SCRATCH0	SPRN_SPRG2
 #define SPRN_SPRG_HPACA		SPRN_HSPRG0
 #define SPRN_SPRG_HSCRATCH0	SPRN_HSPRG1
+#define SPRN_SPRG_VDSO_READ	SPRN_USPRG3
+#define SPRN_SPRG_VDSO_WRITE	SPRN_SPRG3
 
 #define GET_PACA(rX)					\
 	BEGIN_FTR_SECTION_NESTED(66);			\
@@ -983,6 +988,8 @@
 #define SPRN_SPRG_TLB_SCRATCH	SPRN_SPRG6
 #define SPRN_SPRG_GEN_SCRATCH	SPRN_SPRG0
 #define SPRN_SPRG_GDBELL_SCRATCH SPRN_SPRG_GEN_SCRATCH
+#define SPRN_SPRG_VDSO_READ	SPRN_USPRG7
+#define SPRN_SPRG_VDSO_WRITE	SPRN_SPRG7
 
 #define SET_PACA(rX)	mtspr	SPRN_SPRG_PACA,rX
 #define GET_PACA(rX)	mfspr	rX,SPRN_SPRG_PACA
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index b5aacf7..dba8140 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -253,7 +253,7 @@ int main(void)
 	DEFINE(PACA_SYSTEM_TIME, offsetof(struct paca_struct, system_time));
 	DEFINE(PACA_TRAP_SAVE, offsetof(struct paca_struct, trap_save));
 	DEFINE(PACA_NAPSTATELOST, offsetof(struct paca_struct, nap_state_lost));
-	DEFINE(PACA_SPRG3, offsetof(struct paca_struct, sprg3));
+	DEFINE(PACA_SPRG_VDSO, offsetof(struct paca_struct, sprg_vdso));
 #endif /* CONFIG_PPC64 */
 
 	/* RTAS */
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 41380a4..89e1133 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -55,7 +55,6 @@
 	mfspr	r13,SPRN_SPRG_PACA;	/* get PACA */			    \
 	std	r10,PACA_EX##type+EX_R10(r13);				    \
 	std	r11,PACA_EX##type+EX_R11(r13);				    \
-	PROLOG_STORE_RESTORE_SCRATCH_##type;				    \
 	mfcr	r10;			/* save CR */			    \
 	mfspr	r11,SPRN_##type##_SRR1;/* what are we coming from */	    \
 	DO_KVM	intnum,SPRN_##type##_SRR1;    /* KVM hook */		    \
@@ -116,20 +115,6 @@
 #define GDBELL_EXCEPTION_PROLOG(n, intnum, addition)			    \
 	EXCEPTION_PROLOG(n, intnum, GDBELL, addition##_GDBELL(n))
 
-/*
- * Store user-visible scratch in PACA exception slots and restore proper value
- */
-#define PROLOG_STORE_RESTORE_SCRATCH_GEN
-#define PROLOG_STORE_RESTORE_SCRATCH_GDBELL
-#define PROLOG_STORE_RESTORE_SCRATCH_DBG
-#define PROLOG_STORE_RESTORE_SCRATCH_MC
-
-#define PROLOG_STORE_RESTORE_SCRATCH_CRIT				    \
-	mfspr	r10,SPRN_SPRG_CRIT_SCRATCH;	/* get r13 */		    \
-	std	r10,PACA_EXCRIT+EX_R13(r13);				    \
-	ld	r11,PACA_SPRG3(r13);					    \
-	mtspr	SPRN_SPRG_CRIT_SCRATCH,r11;
-
 /* Variants of the "addition" argument for the prolog
  */
 #define PROLOG_ADDITION_NONE_GEN(n)
@@ -529,7 +514,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	mtcr	r10
 	ld	r10,PACA_EXCRIT+EX_R10(r13)	/* restore registers */
 	ld	r11,PACA_EXCRIT+EX_R11(r13)
-	ld	r13,PACA_EXCRIT+EX_R13(r13)
+	mfspr	r13,SPRN_SPRG_CRIT_SCRATCH
 	rfci
 
 	/* Normal debug exception */
@@ -542,7 +527,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	/* Now we mash up things to make it look like we are coming on a
 	 * normal exception
 	 */
-	ld	r15,PACA_EXCRIT+EX_R13(r13)
+	mfspr	r15,SPRN_SPRG_CRIT_SCRATCH
 	mtspr	SPRN_SPRG_GEN_SCRATCH,r15
 	mfspr	r14,SPRN_DBSR
 	EXCEPTION_COMMON(0xd00, PACA_EXCRIT, INTS_DISABLE)
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 094e45c..ce74c33 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -715,8 +715,8 @@ int vdso_getcpu_init(void)
 	unsigned long cpu, node, val;
 
 	/*
-	 * SPRG3 contains the CPU in the bottom 16 bits and the NUMA node in
-	 * the next 16 bits. The VDSO uses this to implement getcpu().
+	 * SPRG_VDSO contains the CPU in the bottom 16 bits and the NUMA node
+	 * in the next 16 bits.  The VDSO uses this to implement getcpu().
 	 */
 	cpu = get_cpu();
 	WARN_ON_ONCE(cpu > 0xffff);
@@ -725,8 +725,8 @@ int vdso_getcpu_init(void)
 	WARN_ON_ONCE(node > 0xffff);
 
 	val = (cpu & 0xfff) | ((node & 0xffff) << 16);
-	mtspr(SPRN_SPRG3, val);
-	get_paca()->sprg3 = val;
+	mtspr(SPRN_SPRG_VDSO_WRITE, val);
+	get_paca()->sprg_vdso = val;
 
 	put_cpu();
 
diff --git a/arch/powerpc/kernel/vdso32/getcpu.S b/arch/powerpc/kernel/vdso32/getcpu.S
index 47afd08..23eb9a9 100644
--- a/arch/powerpc/kernel/vdso32/getcpu.S
+++ b/arch/powerpc/kernel/vdso32/getcpu.S
@@ -29,7 +29,7 @@
  */
 V_FUNCTION_BEGIN(__kernel_getcpu)
   .cfi_startproc
-	mfspr	r5,SPRN_USPRG3
+	mfspr	r5,SPRN_SPRG_VDSO_READ
 	cmpdi	cr0,r3,0
 	cmpdi	cr1,r4,0
 	clrlwi  r6,r5,16
diff --git a/arch/powerpc/kernel/vdso64/getcpu.S b/arch/powerpc/kernel/vdso64/getcpu.S
index 47afd08..23eb9a9 100644
--- a/arch/powerpc/kernel/vdso64/getcpu.S
+++ b/arch/powerpc/kernel/vdso64/getcpu.S
@@ -29,7 +29,7 @@
  */
 V_FUNCTION_BEGIN(__kernel_getcpu)
   .cfi_startproc
-	mfspr	r5,SPRN_USPRG3
+	mfspr	r5,SPRN_SPRG_VDSO_READ
 	cmpdi	cr0,r3,0
 	cmpdi	cr1,r4,0
 	clrlwi  r6,r5,16
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index e66d4ec..fbfca57 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -75,8 +75,8 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 
 	/* Restore SPRG3 */
-	ld	r3,PACA_SPRG3(r13)
-	mtspr	SPRN_SPRG3,r3
+	ld	r3,PACA_SPRG_VDSO(r13)
+	mtspr	SPRN_SPRG_VDSO_WRITE,r3
 
 	/* Reload the host's PMU registers */
 	ld	r3, PACALPPACAPTR(r13)	/* is the host using the PMU? */
diff --git a/arch/powerpc/kvm/book3s_interrupts.S b/arch/powerpc/kvm/book3s_interrupts.S
index f779450..3533c99 100644
--- a/arch/powerpc/kvm/book3s_interrupts.S
+++ b/arch/powerpc/kvm/book3s_interrupts.S
@@ -153,8 +153,8 @@ kvm_start_lightweight:
 	 * Reload kernel SPRG3 value.
 	 * No need to save guest value as usermode can't modify SPRG3.
 	 */
-	ld	r3, PACA_SPRG3(r13)
-	mtspr	SPRN_SPRG3, r3
+	ld	r3, PACA_SPRG_VDSO(r13)
+	mtspr	SPRN_SPRG_VDSO_WRITE, r3
 #endif /* CONFIG_PPC_BOOK3S_64 */
 
 	/* R7 = vcpu */
diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S
index e4185f6..99635a3 100644
--- a/arch/powerpc/kvm/bookehv_interrupts.S
+++ b/arch/powerpc/kvm/bookehv_interrupts.S
@@ -229,11 +229,7 @@
 	stw	r10, VCPU_CR(r4)
 	PPC_STL r11, VCPU_GPR(R4)(r4)
 	PPC_STL	r5, VCPU_GPR(R5)(r4)
-	.if \type == EX_CRIT
-	PPC_LL	r5, (\paca_ex + EX_R13)(r13)
-	.else
 	mfspr	r5, \scratch
-	.endif
 	PPC_STL	r6, VCPU_GPR(R6)(r4)
 	PPC_STL	r8, VCPU_GPR(R8)(r4)
 	PPC_STL	r9, VCPU_GPR(R9)(r4)
@@ -435,10 +431,16 @@ _GLOBAL(kvmppc_resume_host)
 	PPC_STL	r5, VCPU_LR(r4)
 	mfspr	r7, SPRN_SPRG5
 	stw	r3, VCPU_VRSAVE(r4)
+#ifdef CONFIG_64BIT
+	PPC_LL	r3, PACA_SPRG_VDSO(r13)
+#endif
 	PPC_STD(r6, VCPU_SHARED_SPRG4, r11)
 	mfspr	r8, SPRN_SPRG6
 	PPC_STD(r7, VCPU_SHARED_SPRG5, r11)
 	mfspr	r9, SPRN_SPRG7
+#ifdef CONFIG_64BIT
+	mtspr	SPRN_SPRG_VDSO_WRITE, r3
+#endif
 	PPC_STD(r8, VCPU_SHARED_SPRG6, r11)
 	mfxer	r3
 	PPC_STD(r9, VCPU_SHARED_SPRG7, r11)
-- 
1.8.3.2

[PATCH 06/10] powerpc/booke64: Use SPRG_TLB_EXFRAME on bolted handlers

[Scott Wood]

While bolted handlers (including e6500) do not need to deal with a TLB
miss recursively causing another TLB miss, nested TLB misses can still
happen with crit/mc/debug exceptions -- so we still need to honor
SPRG_TLB_EXFRAME.

We don't need to spend time modifying it in the TLB miss fastpath,
though -- the special level exception will handle that.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: kvm-ppc@vger.kernel.org
---
 arch/powerpc/include/asm/exception-64e.h    | 10 -------
 arch/powerpc/include/asm/kvm_booke_hv_asm.h |  8 ++++--
 arch/powerpc/kvm/bookehv_interrupts.S       | 14 +++++++--
 arch/powerpc/mm/tlb_low_64e.S               | 44 ++++++++++++++++++-----------
 4 files changed, 45 insertions(+), 31 deletions(-)

diff --git a/arch/powerpc/include/asm/exception-64e.h b/arch/powerpc/include/asm/exception-64e.h
index e73452f..a563d9af 100644
--- a/arch/powerpc/include/asm/exception-64e.h
+++ b/arch/powerpc/include/asm/exception-64e.h
@@ -172,16 +172,6 @@ exc_##label##_book3e:
 	ld	r9,EX_TLB_R9(r12);					    \
 	ld	r8,EX_TLB_R8(r12);					    \
 	mtlr	r16;
-#define TLB_MISS_PROLOG_STATS_BOLTED						    \
-	mflr	r10;							    \
-	std	r8,PACA_EXTLB+EX_TLB_R8(r13);				    \
-	std	r9,PACA_EXTLB+EX_TLB_R9(r13);				    \
-	std	r10,PACA_EXTLB+EX_TLB_LR(r13);
-#define TLB_MISS_RESTORE_STATS_BOLTED					            \
-	ld	r16,PACA_EXTLB+EX_TLB_LR(r13);				    \
-	ld	r9,PACA_EXTLB+EX_TLB_R9(r13);				    \
-	ld	r8,PACA_EXTLB+EX_TLB_R8(r13);				    \
-	mtlr	r16;
 #define TLB_MISS_STATS_D(name)						    \
 	addi	r9,r13,MMSTAT_DSTATS+name;				    \
 	bl	.tlb_stat_inc;
diff --git a/arch/powerpc/include/asm/kvm_booke_hv_asm.h b/arch/powerpc/include/asm/kvm_booke_hv_asm.h
index c3e3fd5..e5f048b 100644
--- a/arch/powerpc/include/asm/kvm_booke_hv_asm.h
+++ b/arch/powerpc/include/asm/kvm_booke_hv_asm.h
@@ -45,10 +45,12 @@
  *
  * Expected inputs (TLB exception type):
  *  r10 = saved CR
+ *  r12 = extlb pointer
  *  r13 = PACA_POINTER
- *  *(r13 + PACA_EX##type + EX_TLB_R10) = saved r10
- *  *(r13 + PACA_EX##type + EX_TLB_R11) = saved r11
- *  SPRN_SPRG_GEN_SCRATCH = saved r13
+ *  *(r12 + EX_TLB_R10) = saved r10
+ *  *(r12 + EX_TLB_R11) = saved r11
+ *  *(r12 + EX_TLB_R13) = saved r13
+ *  SPRN_SPRG_GEN_SCRATCH = saved r12
  *
  * Only the bolted version of TLB miss exception handlers is supported now.
  */
diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S
index 99635a3..890e338 100644
--- a/arch/powerpc/kvm/bookehv_interrupts.S
+++ b/arch/powerpc/kvm/bookehv_interrupts.S
@@ -229,13 +229,20 @@
 	stw	r10, VCPU_CR(r4)
 	PPC_STL r11, VCPU_GPR(R4)(r4)
 	PPC_STL	r5, VCPU_GPR(R5)(r4)
-	mfspr	r5, \scratch
 	PPC_STL	r6, VCPU_GPR(R6)(r4)
 	PPC_STL	r8, VCPU_GPR(R8)(r4)
 	PPC_STL	r9, VCPU_GPR(R9)(r4)
-	PPC_STL r5, VCPU_GPR(R13)(r4)
+	.if \type == EX_TLB
+	PPC_LL	r5, EX_TLB_R13(r12)
+	PPC_LL	r6, EX_TLB_R10(r12)
+	PPC_LL	r8, EX_TLB_R11(r12)
+	mfspr	r12, \scratch
+	.else
+	mfspr	r5, \scratch
 	PPC_LL	r6, (\paca_ex + \ex_r10)(r13)
 	PPC_LL	r8, (\paca_ex + \ex_r11)(r13)
+	.endif
+	PPC_STL r5, VCPU_GPR(R13)(r4)
 	PPC_STL r3, VCPU_GPR(R3)(r4)
 	PPC_STL r7, VCPU_GPR(R7)(r4)
 	PPC_STL r12, VCPU_GPR(R12)(r4)
@@ -444,6 +451,9 @@ _GLOBAL(kvmppc_resume_host)
 	PPC_STD(r8, VCPU_SHARED_SPRG6, r11)
 	mfxer	r3
 	PPC_STD(r9, VCPU_SHARED_SPRG7, r11)
+#ifdef CONFIG_64BIT
+	mtspr	SPRN_SPRG_VDSO_WRITE, r3
+#endif
 
 	/* save guest MAS registers and restore host mas4 & mas6 */
 	mfspr	r5, SPRN_MAS0
diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S
index 1e50249..356e8b4 100644
--- a/arch/powerpc/mm/tlb_low_64e.S
+++ b/arch/powerpc/mm/tlb_low_64e.S
@@ -39,37 +39,49 @@
  *                                                                    *
  **********************************************************************/
 
+/*
+ * Note that, unlike non-bolted handlers, TLB_EXFRAME is not
+ * modified by the TLB miss handlers themselves, since the TLB miss
+ * handler code will not itself cause a recursive TLB miss.
+ *
+ * TLB_EXFRAME will be modified when crit/mc/debug exceptions are
+ * entered/exited.
+ */
 .macro tlb_prolog_bolted intnum addr
-	mtspr	SPRN_SPRG_GEN_SCRATCH,r13
+	mtspr	SPRN_SPRG_GEN_SCRATCH,r12
+	mfspr	r12,SPRN_SPRG_TLB_EXFRAME
+	std	r13,EX_TLB_R13(r12)
+	std	r10,EX_TLB_R10(r12)
 	mfspr	r13,SPRN_SPRG_PACA
-	std	r10,PACA_EXTLB+EX_TLB_R10(r13)
+
 	mfcr	r10
-	std	r11,PACA_EXTLB+EX_TLB_R11(r13)
+	std	r11,EX_TLB_R11(r12)
 #ifdef CONFIG_KVM_BOOKE_HV
 BEGIN_FTR_SECTION
 	mfspr	r11, SPRN_SRR1
 END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 #endif
 	DO_KVM	\intnum, SPRN_SRR1
-	std	r16,PACA_EXTLB+EX_TLB_R16(r13)
+	std	r16,EX_TLB_R16(r12)
 	mfspr	r16,\addr		/* get faulting address */
-	std	r14,PACA_EXTLB+EX_TLB_R14(r13)
+	std	r14,EX_TLB_R14(r12)
 	ld	r14,PACAPGD(r13)
-	std	r15,PACA_EXTLB+EX_TLB_R15(r13)
-	std	r10,PACA_EXTLB+EX_TLB_CR(r13)
-	TLB_MISS_PROLOG_STATS_BOLTED
+	std	r15,EX_TLB_R15(r12)
+	std	r10,EX_TLB_CR(r12)
+	TLB_MISS_PROLOG_STATS
 .endm
 
 .macro tlb_epilog_bolted
-	ld	r14,PACA_EXTLB+EX_TLB_CR(r13)
-	ld	r10,PACA_EXTLB+EX_TLB_R10(r13)
-	ld	r11,PACA_EXTLB+EX_TLB_R11(r13)
+	ld	r14,EX_TLB_CR(r12)
+	ld	r10,EX_TLB_R10(r12)
+	ld	r11,EX_TLB_R11(r12)
+	ld	r13,EX_TLB_R13(r12)
 	mtcr	r14
-	ld	r14,PACA_EXTLB+EX_TLB_R14(r13)
-	ld	r15,PACA_EXTLB+EX_TLB_R15(r13)
-	TLB_MISS_RESTORE_STATS_BOLTED
-	ld	r16,PACA_EXTLB+EX_TLB_R16(r13)
-	mfspr	r13,SPRN_SPRG_GEN_SCRATCH
+	ld	r14,EX_TLB_R14(r12)
+	ld	r15,EX_TLB_R15(r12)
+	TLB_MISS_RESTORE_STATS
+	ld	r16,EX_TLB_R16(r12)
+	mfspr	r12,SPRN_SPRG_GEN_SCRATCH
 .endm
 
 /* Data TLB miss */
-- 
1.8.3.2

[PATCH 07/10] powerpc/booke64: Remove ints from EXCEPTION_COMMON

[Scott Wood]

The ints parameter was used to optionally insert RECONCILE_IRQ_STATE
into EXCEPTION_COMMON.  However, since it came at the end of
EXCEPTION_COMMON, there was no real benefit for it to be there as
opposed to being called separately by the caller of EXCEPTION_COMMON.

The ints parameter was causing some hassle when trying to add an extra
macro layer.  Besides avoiding that, moving "ints" to the caller makes
the code simpler by:
 - avoiding the asymmetry where INTS_RESTORE_HARD is called separately
by the individual exception, but INTS_DISABLE was not
 - removing the no-op INTS_KEEP
 - not having an unnecessary macro parameter

It also turned out to be necessary to delay the INTS_DISABLE
in the case of special level exceptions until after we saved the
old value of PACAIRQHAPPENED.

Signed-off-by: Scott Wood <scottwood@freescale.com>
---
 arch/powerpc/kernel/exceptions-64e.S | 82 ++++++++++++++++++++----------------
 1 file changed, 46 insertions(+), 36 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 89e1133..0204c39 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -151,7 +151,7 @@
 /* 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)					    \
+#define EXCEPTION_COMMON(n, excf)					    \
 exc_##n##_common:							    \
 	std	r0,GPR0(r1);		/* save r0 in stackframe */	    \
 	std	r2,GPR2(r1);		/* save r2 in stackframe */	    \
@@ -188,24 +188,20 @@ exc_##n##_common:							    \
 	std	r11,SOFTE(r1);		/* and save it to stackframe */     \
 	std	r12,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame */	    \
 	std	r3,_TRAP(r1);		/* set trap number		*/  \
-	std	r0,RESULT(r1);		/* clear regs->result */	    \
-	ints;
+	std	r0,RESULT(r1);		/* clear regs->result */
 
-/* Variants for the "ints" argument. This one does nothing when we want
- * to keep interrupts in their original state
- */
-#define INTS_KEEP
-
-/* 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, and then reconcile irq state.
+/*
+ * This 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, and then reconcile irq state.
  */
 #define INTS_DISABLE	RECONCILE_IRQ_STATE(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
+/*
+ * This is called by exceptions that don't use INTS_DISABLE (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
@@ -263,7 +259,8 @@ exc_##n##_bad_stack:							    \
 #define MASKABLE_EXCEPTION(trapnum, intnum, label, hdlr, ack)		\
 	START_EXCEPTION(label);						\
 	NORMAL_EXCEPTION_PROLOG(trapnum, intnum, PROLOG_ADDITION_MASKABLE)\
-	EXCEPTION_COMMON(trapnum, PACA_EXGEN, INTS_DISABLE)		\
+	EXCEPTION_COMMON(trapnum, PACA_EXGEN)				\
+	INTS_DISABLE;							\
 	ack(r8);							\
 	CHECK_NAPPING();						\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;				\
@@ -318,7 +315,8 @@ interrupt_end_book3e:
 	START_EXCEPTION(critical_input);
 	CRIT_EXCEPTION_PROLOG(0x100, BOOKE_INTERRUPT_CRITICAL,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x100, PACA_EXCRIT, INTS_DISABLE)
+//	EXCEPTION_COMMON(0x100, PACA_EXCRIT)
+//	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
 //	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -330,7 +328,8 @@ interrupt_end_book3e:
 	START_EXCEPTION(machine_check);
 	MC_EXCEPTION_PROLOG(0x000, BOOKE_INTERRUPT_MACHINE_CHECK,
 			    PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x000, PACA_EXMC, INTS_DISABLE)
+//	EXCEPTION_COMMON(0x000, PACA_EXMC)
+//	INTS_DISABLE
 //	bl	special_reg_save_mc
 //	addi	r3,r1,STACK_FRAME_OVERHEAD
 //	CHECK_NAPPING();
@@ -344,7 +343,8 @@ interrupt_end_book3e:
 				PROLOG_ADDITION_2REGS)
 	mfspr	r14,SPRN_DEAR
 	mfspr	r15,SPRN_ESR
-	EXCEPTION_COMMON(0x300, PACA_EXGEN, INTS_DISABLE)
+	EXCEPTION_COMMON(0x300, PACA_EXGEN)
+	INTS_DISABLE
 	b	storage_fault_common
 
 /* Instruction Storage Interrupt */
@@ -353,7 +353,8 @@ interrupt_end_book3e:
 				PROLOG_ADDITION_2REGS)
 	li	r15,0
 	mr	r14,r10
-	EXCEPTION_COMMON(0x400, PACA_EXGEN, INTS_DISABLE)
+	EXCEPTION_COMMON(0x400, PACA_EXGEN)
+	INTS_DISABLE
 	b	storage_fault_common
 
 /* External Input Interrupt */
@@ -366,7 +367,7 @@ interrupt_end_book3e:
 				PROLOG_ADDITION_2REGS)
 	mfspr	r14,SPRN_DEAR
 	mfspr	r15,SPRN_ESR
-	EXCEPTION_COMMON(0x600, PACA_EXGEN, INTS_KEEP)
+	EXCEPTION_COMMON(0x600, PACA_EXGEN)
 	b	alignment_more	/* no room, go out of line */
 
 /* Program Interrupt */
@@ -374,7 +375,8 @@ interrupt_end_book3e:
 	NORMAL_EXCEPTION_PROLOG(0x700, BOOKE_INTERRUPT_PROGRAM,
 				PROLOG_ADDITION_1REG)
 	mfspr	r14,SPRN_ESR
-	EXCEPTION_COMMON(0x700, PACA_EXGEN, INTS_DISABLE)
+	EXCEPTION_COMMON(0x700, PACA_EXGEN)
+	INTS_DISABLE
 	std	r14,_DSISR(r1)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	ld	r14,PACA_EXGEN+EX_R14(r13)
@@ -387,7 +389,7 @@ interrupt_end_book3e:
 	NORMAL_EXCEPTION_PROLOG(0x800, BOOKE_INTERRUPT_FP_UNAVAIL,
 				PROLOG_ADDITION_NONE)
 	/* we can probably do a shorter exception entry for that one... */
-	EXCEPTION_COMMON(0x800, PACA_EXGEN, INTS_KEEP)
+	EXCEPTION_COMMON(0x800, PACA_EXGEN)
 	ld	r12,_MSR(r1)
 	andi.	r0,r12,MSR_PR;
 	beq-	1f
@@ -404,7 +406,7 @@ interrupt_end_book3e:
 	NORMAL_EXCEPTION_PROLOG(0x200, BOOKE_INTERRUPT_SPE_ALTIVEC_UNAVAIL,
 				PROLOG_ADDITION_NONE)
 	/* we can probably do a shorter exception entry for that one... */
-	EXCEPTION_COMMON(0x200, PACA_EXGEN, INTS_KEEP)
+	EXCEPTION_COMMON(0x200, PACA_EXGEN)
 #ifdef CONFIG_ALTIVEC
 BEGIN_FTR_SECTION
 	ld	r12,_MSR(r1)
@@ -426,7 +428,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	NORMAL_EXCEPTION_PROLOG(0x220,
 				BOOKE_INTERRUPT_SPE_FP_DATA_ALTIVEC_ASSIST,
 				PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x220, PACA_EXGEN, INTS_DISABLE)
+	EXCEPTION_COMMON(0x220, PACA_EXGEN)
+	INTS_DISABLE
 	bl	.save_nvgprs
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 #ifdef CONFIG_ALTIVEC
@@ -451,7 +454,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	START_EXCEPTION(watchdog);
 	CRIT_EXCEPTION_PROLOG(0x9f0, BOOKE_INTERRUPT_WATCHDOG,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x9f0, PACA_EXCRIT, INTS_DISABLE)
+//	EXCEPTION_COMMON(0x9f0, PACA_EXCRIT)
+//	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
 //	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -471,7 +475,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	START_EXCEPTION(ap_unavailable);
 	NORMAL_EXCEPTION_PROLOG(0xf20, BOOKE_INTERRUPT_AP_UNAVAIL,
 				PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0xf20, PACA_EXGEN, INTS_DISABLE)
+	EXCEPTION_COMMON(0xf20, PACA_EXGEN)
+	INTS_DISABLE
 	bl	.save_nvgprs
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.unknown_exception
@@ -530,7 +535,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	mfspr	r15,SPRN_SPRG_CRIT_SCRATCH
 	mtspr	SPRN_SPRG_GEN_SCRATCH,r15
 	mfspr	r14,SPRN_DBSR
-	EXCEPTION_COMMON(0xd00, PACA_EXCRIT, INTS_DISABLE)
+	EXCEPTION_COMMON(0xd00, PACA_EXCRIT)
+	INTS_DISABLE
 	std	r14,_DSISR(r1)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	mr	r4,r14
@@ -596,7 +602,8 @@ kernel_dbg_exc:
 	mfspr	r15,SPRN_SPRG_DBG_SCRATCH
 	mtspr	SPRN_SPRG_GEN_SCRATCH,r15
 	mfspr	r14,SPRN_DBSR
-	EXCEPTION_COMMON(0xd08, PACA_EXDBG, INTS_DISABLE)
+	EXCEPTION_COMMON(0xd08, PACA_EXDBG)
+	INTS_DISABLE
 	std	r14,_DSISR(r1)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	mr	r4,r14
@@ -609,7 +616,8 @@ kernel_dbg_exc:
 	START_EXCEPTION(perfmon);
 	NORMAL_EXCEPTION_PROLOG(0x260, BOOKE_INTERRUPT_PERFORMANCE_MONITOR,
 				PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x260, PACA_EXGEN, INTS_DISABLE)
+	EXCEPTION_COMMON(0x260, PACA_EXGEN)
+	INTS_DISABLE
 	CHECK_NAPPING()
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.performance_monitor_exception
@@ -623,7 +631,8 @@ kernel_dbg_exc:
 	START_EXCEPTION(doorbell_crit);
 	CRIT_EXCEPTION_PROLOG(0x2a0, BOOKE_INTERRUPT_DOORBELL_CRITICAL,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x2a0, PACA_EXCRIT, INTS_DISABLE)
+//	EXCEPTION_COMMON(0x2a0, PACA_EXCRIT)
+//	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
 //	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -638,7 +647,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(guest_doorbell);
 	GDBELL_EXCEPTION_PROLOG(0x2c0, BOOKE_INTERRUPT_GUEST_DBELL,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x2c0, PACA_EXGEN, INTS_KEEP)
+	EXCEPTION_COMMON(0x2c0, PACA_EXGEN)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
@@ -649,7 +658,8 @@ kernel_dbg_exc:
 	START_EXCEPTION(guest_doorbell_crit);
 	CRIT_EXCEPTION_PROLOG(0x2e0, BOOKE_INTERRUPT_GUEST_DBELL_CRIT,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x2e0, PACA_EXCRIT, INTS_DISABLE)
+//	EXCEPTION_COMMON(0x2e0, PACA_EXCRIT)
+//	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
 //	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -661,7 +671,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(hypercall);
 	NORMAL_EXCEPTION_PROLOG(0x310, BOOKE_INTERRUPT_HV_SYSCALL,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x310, PACA_EXGEN, INTS_KEEP)
+	EXCEPTION_COMMON(0x310, PACA_EXGEN)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
@@ -672,7 +682,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(ehpriv);
 	NORMAL_EXCEPTION_PROLOG(0x320, BOOKE_INTERRUPT_HV_PRIV,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x320, PACA_EXGEN, INTS_KEEP)
+	EXCEPTION_COMMON(0x320, PACA_EXGEN)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
@@ -683,7 +693,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(lrat_error);
 	NORMAL_EXCEPTION_PROLOG(0x340, BOOKE_INTERRUPT_LRAT_ERROR,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x340, PACA_EXGEN, INTS_KEEP)
+	EXCEPTION_COMMON(0x340, PACA_EXGEN)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
-- 
1.8.3.2

[PATCH 08/10] powerpc/booke64: Add crit/mc/debug support to EXCEPTION_COMMON

[Scott Wood]

Use the proper scratch SPRG and PACA region.  Introduce level-specific
macros to simplify usage and avoid needing to do a bunch of token
pasting throughout EXCEPTION_COMMON().

Now that EXCEPTION_COMMON_DBG() is properly using the debug scratch
register, there's no more need for the caller to move the value to the
GEN scratch first.

Signed-off-by: Scott Wood <scottwood@freescale.com>
---
 arch/powerpc/kernel/exceptions-64e.S | 63 +++++++++++++++++++-----------------
 1 file changed, 33 insertions(+), 30 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 0204c39..2beb5bd 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -148,10 +148,8 @@
 	std	r15,PACA_EXMC+EX_R15(r13)
 
 
-/* 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)					    \
+/* Core exception code for all exceptions except TLB misses. */
+#define EXCEPTION_COMMON_LVL(n, scratch, excf)				    \
 exc_##n##_common:							    \
 	std	r0,GPR0(r1);		/* save r0 in stackframe */	    \
 	std	r2,GPR2(r1);		/* save r2 in stackframe */	    \
@@ -164,7 +162,7 @@ exc_##n##_common:							    \
 	ACCOUNT_CPU_USER_ENTRY(r10,r11);/* accounting (uses cr0+eq) */	    \
 2:	ld	r3,excf+EX_R10(r13);	/* get back r10 */		    \
 	ld	r4,excf+EX_R11(r13);	/* get back r11 */		    \
-	mfspr	r5,SPRN_SPRG_GEN_SCRATCH;/* get back r13 */		    \
+	mfspr	r5,scratch;		/* get back r13 */		    \
 	std	r12,GPR12(r1);		/* save r12 in stackframe */	    \
 	ld	r2,PACATOC(r13);	/* get kernel TOC into r2 */	    \
 	mflr	r6;			/* save LR in stackframe */	    \
@@ -190,6 +188,15 @@ exc_##n##_common:							    \
 	std	r3,_TRAP(r1);		/* set trap number		*/  \
 	std	r0,RESULT(r1);		/* clear regs->result */
 
+#define EXCEPTION_COMMON(n) \
+	EXCEPTION_COMMON_LVL(n, SPRN_SPRG_GEN_SCRATCH, PACA_EXGEN)
+#define EXCEPTION_COMMON_CRIT(n) \
+	EXCEPTION_COMMON_LVL(n, SPRN_SPRG_CRIT_SCRATCH, PACA_EXCRIT)
+#define EXCEPTION_COMMON_MC(n) \
+	EXCEPTION_COMMON_LVL(n, SPRN_SPRG_MC_SCRATCH, PACA_EXMC)
+#define EXCEPTION_COMMON_DBG(n) \
+	EXCEPTION_COMMON_LVL(n, SPRN_SPRG_DBG_SCRATCH, PACA_EXDBG)
+
 /*
  * This 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
@@ -259,7 +266,7 @@ exc_##n##_bad_stack:							    \
 #define MASKABLE_EXCEPTION(trapnum, intnum, label, hdlr, ack)		\
 	START_EXCEPTION(label);						\
 	NORMAL_EXCEPTION_PROLOG(trapnum, intnum, PROLOG_ADDITION_MASKABLE)\
-	EXCEPTION_COMMON(trapnum, PACA_EXGEN)				\
+	EXCEPTION_COMMON(trapnum)					\
 	INTS_DISABLE;							\
 	ack(r8);							\
 	CHECK_NAPPING();						\
@@ -315,7 +322,7 @@ interrupt_end_book3e:
 	START_EXCEPTION(critical_input);
 	CRIT_EXCEPTION_PROLOG(0x100, BOOKE_INTERRUPT_CRITICAL,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x100, PACA_EXCRIT)
+//	EXCEPTION_COMMON_CRIT(0x100)
 //	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
@@ -328,7 +335,7 @@ interrupt_end_book3e:
 	START_EXCEPTION(machine_check);
 	MC_EXCEPTION_PROLOG(0x000, BOOKE_INTERRUPT_MACHINE_CHECK,
 			    PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x000, PACA_EXMC)
+//	EXCEPTION_COMMON_MC(0x000)
 //	INTS_DISABLE
 //	bl	special_reg_save_mc
 //	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -343,7 +350,7 @@ interrupt_end_book3e:
 				PROLOG_ADDITION_2REGS)
 	mfspr	r14,SPRN_DEAR
 	mfspr	r15,SPRN_ESR
-	EXCEPTION_COMMON(0x300, PACA_EXGEN)
+	EXCEPTION_COMMON(0x300)
 	INTS_DISABLE
 	b	storage_fault_common
 
@@ -353,7 +360,7 @@ interrupt_end_book3e:
 				PROLOG_ADDITION_2REGS)
 	li	r15,0
 	mr	r14,r10
-	EXCEPTION_COMMON(0x400, PACA_EXGEN)
+	EXCEPTION_COMMON(0x400)
 	INTS_DISABLE
 	b	storage_fault_common
 
@@ -367,7 +374,7 @@ interrupt_end_book3e:
 				PROLOG_ADDITION_2REGS)
 	mfspr	r14,SPRN_DEAR
 	mfspr	r15,SPRN_ESR
-	EXCEPTION_COMMON(0x600, PACA_EXGEN)
+	EXCEPTION_COMMON(0x600)
 	b	alignment_more	/* no room, go out of line */
 
 /* Program Interrupt */
@@ -375,7 +382,7 @@ interrupt_end_book3e:
 	NORMAL_EXCEPTION_PROLOG(0x700, BOOKE_INTERRUPT_PROGRAM,
 				PROLOG_ADDITION_1REG)
 	mfspr	r14,SPRN_ESR
-	EXCEPTION_COMMON(0x700, PACA_EXGEN)
+	EXCEPTION_COMMON(0x700)
 	INTS_DISABLE
 	std	r14,_DSISR(r1)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -389,7 +396,7 @@ interrupt_end_book3e:
 	NORMAL_EXCEPTION_PROLOG(0x800, BOOKE_INTERRUPT_FP_UNAVAIL,
 				PROLOG_ADDITION_NONE)
 	/* we can probably do a shorter exception entry for that one... */
-	EXCEPTION_COMMON(0x800, PACA_EXGEN)
+	EXCEPTION_COMMON(0x800)
 	ld	r12,_MSR(r1)
 	andi.	r0,r12,MSR_PR;
 	beq-	1f
@@ -406,7 +413,7 @@ interrupt_end_book3e:
 	NORMAL_EXCEPTION_PROLOG(0x200, BOOKE_INTERRUPT_SPE_ALTIVEC_UNAVAIL,
 				PROLOG_ADDITION_NONE)
 	/* we can probably do a shorter exception entry for that one... */
-	EXCEPTION_COMMON(0x200, PACA_EXGEN)
+	EXCEPTION_COMMON(0x200)
 #ifdef CONFIG_ALTIVEC
 BEGIN_FTR_SECTION
 	ld	r12,_MSR(r1)
@@ -428,7 +435,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	NORMAL_EXCEPTION_PROLOG(0x220,
 				BOOKE_INTERRUPT_SPE_FP_DATA_ALTIVEC_ASSIST,
 				PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x220, PACA_EXGEN)
+	EXCEPTION_COMMON(0x220)
 	INTS_DISABLE
 	bl	.save_nvgprs
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -454,7 +461,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	START_EXCEPTION(watchdog);
 	CRIT_EXCEPTION_PROLOG(0x9f0, BOOKE_INTERRUPT_WATCHDOG,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x9f0, PACA_EXCRIT)
+//	EXCEPTION_COMMON_CRIT(0x9f0)
 //	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
@@ -475,7 +482,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	START_EXCEPTION(ap_unavailable);
 	NORMAL_EXCEPTION_PROLOG(0xf20, BOOKE_INTERRUPT_AP_UNAVAIL,
 				PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0xf20, PACA_EXGEN)
+	EXCEPTION_COMMON(0xf20)
 	INTS_DISABLE
 	bl	.save_nvgprs
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -532,10 +539,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 	/* Now we mash up things to make it look like we are coming on a
 	 * normal exception
 	 */
-	mfspr	r15,SPRN_SPRG_CRIT_SCRATCH
-	mtspr	SPRN_SPRG_GEN_SCRATCH,r15
 	mfspr	r14,SPRN_DBSR
-	EXCEPTION_COMMON(0xd00, PACA_EXCRIT)
+	EXCEPTION_COMMON_CRIT(0xd00)
 	INTS_DISABLE
 	std	r14,_DSISR(r1)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -599,10 +604,8 @@ kernel_dbg_exc:
 	/* Now we mash up things to make it look like we are coming on a
 	 * normal exception
 	 */
-	mfspr	r15,SPRN_SPRG_DBG_SCRATCH
-	mtspr	SPRN_SPRG_GEN_SCRATCH,r15
 	mfspr	r14,SPRN_DBSR
-	EXCEPTION_COMMON(0xd08, PACA_EXDBG)
+	EXCEPTION_COMMON_DBG(0xd08)
 	INTS_DISABLE
 	std	r14,_DSISR(r1)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -616,7 +619,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(perfmon);
 	NORMAL_EXCEPTION_PROLOG(0x260, BOOKE_INTERRUPT_PERFORMANCE_MONITOR,
 				PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x260, PACA_EXGEN)
+	EXCEPTION_COMMON(0x260)
 	INTS_DISABLE
 	CHECK_NAPPING()
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -631,7 +634,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(doorbell_crit);
 	CRIT_EXCEPTION_PROLOG(0x2a0, BOOKE_INTERRUPT_DOORBELL_CRITICAL,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x2a0, PACA_EXCRIT)
+//	EXCEPTION_COMMON_CRIT(0x2a0)
 //	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
@@ -647,7 +650,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(guest_doorbell);
 	GDBELL_EXCEPTION_PROLOG(0x2c0, BOOKE_INTERRUPT_GUEST_DBELL,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x2c0, PACA_EXGEN)
+	EXCEPTION_COMMON(0x2c0)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
@@ -658,7 +661,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(guest_doorbell_crit);
 	CRIT_EXCEPTION_PROLOG(0x2e0, BOOKE_INTERRUPT_GUEST_DBELL_CRIT,
 			      PROLOG_ADDITION_NONE)
-//	EXCEPTION_COMMON(0x2e0, PACA_EXCRIT)
+//	EXCEPTION_COMMON_CRIT(0x2e0)
 //	INTS_DISABLE
 //	bl	special_reg_save_crit
 //	CHECK_NAPPING();
@@ -671,7 +674,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(hypercall);
 	NORMAL_EXCEPTION_PROLOG(0x310, BOOKE_INTERRUPT_HV_SYSCALL,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x310, PACA_EXGEN)
+	EXCEPTION_COMMON(0x310)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
@@ -682,7 +685,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(ehpriv);
 	NORMAL_EXCEPTION_PROLOG(0x320, BOOKE_INTERRUPT_HV_PRIV,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x320, PACA_EXGEN)
+	EXCEPTION_COMMON(0x320)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
@@ -693,7 +696,7 @@ kernel_dbg_exc:
 	START_EXCEPTION(lrat_error);
 	NORMAL_EXCEPTION_PROLOG(0x340, BOOKE_INTERRUPT_LRAT_ERROR,
 			        PROLOG_ADDITION_NONE)
-	EXCEPTION_COMMON(0x340, PACA_EXGEN)
+	EXCEPTION_COMMON(0x340)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	.save_nvgprs
 	INTS_RESTORE_HARD
-- 
1.8.3.2

[PATCH 09/10] powerpc/booke64: Critical and machine check exception support

[Scott Wood]

Add special state saving for critical and machine check exceptions.

Most of this code could be used to handle debug exceptions taken from
kernel space, but actually doing so is outside the scope of this patch.

The various critical and machine check exceptions now point to their
real handlers, rather than hanging the kernel.

Signed-off-by: Scott Wood <scottwood@freescale.com>
---
 arch/powerpc/include/asm/paca.h      |   7 +-
 arch/powerpc/kernel/exceptions-64e.S | 343 +++++++++++++++++++++++++++++------
 arch/powerpc/mm/tlb_nohash.c         |  11 ++
 3 files changed, 300 insertions(+), 61 deletions(-)

diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 948f01a..8e956a0 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 2beb5bd..c1bee3c 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 b37a58e..ae3d5b7 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);
-- 
1.8.3.2

[PATCH 10/10] Revert "powerpc/watchdog: Don't enable interrupt on PPC64 BookE"

[Scott Wood]

This reverts commit 3978bdb4ed653342b0be66c031bf61b72cc55d60, now that
critical interrupts are properly supported on ppc64 booke.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
---
 drivers/watchdog/booke_wdt.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/drivers/watchdog/booke_wdt.c b/drivers/watchdog/booke_wdt.c
index f1b8d55..a8dbceb3 100644
--- a/drivers/watchdog/booke_wdt.c
+++ b/drivers/watchdog/booke_wdt.c
@@ -138,14 +138,6 @@ static void __booke_wdt_enable(void *data)
 	val &= ~WDTP_MASK;
 	val |= (TCR_WIE|TCR_WRC(WRC_CHIP)|WDTP(booke_wdt_period));
 
-#ifdef CONFIG_PPC_BOOK3E_64
-	/*
-	 * Crit ints are currently broken on PPC64 Book-E, so
-	 * just disable them for now.
-	 */
-	val &= ~TCR_WIE;
-#endif
-
 	mtspr(SPRN_TCR, val);
 }
 
-- 
1.8.3.2

Re: [PATCH 06/10] powerpc/booke64: Use SPRG_TLB_EXFRAME on bolted handlers

[Scott Wood]

On Thu, 2014-03-13 at 19:00 -0500, Scott Wood wrote:
> @@ -444,6 +451,9 @@ _GLOBAL(kvmppc_resume_host)
>  	PPC_STD(r8, VCPU_SHARED_SPRG6, r11)
>  	mfxer	r3
>  	PPC_STD(r9, VCPU_SHARED_SPRG7, r11)
> +#ifdef CONFIG_64BIT
> +	mtspr	SPRN_SPRG_VDSO_WRITE, r3
> +#endif

Oops, this hunk was a patch shuffling accident.  v2 coming.

-Scott

Re: [PATCH 10/10] Revert "powerpc/watchdog: Don't enable interrupt on PPC64 BookE"

[Wim Van Sebroeck]

Hi Scott,

> This reverts commit 3978bdb4ed653342b0be66c031bf61b72cc55d60, now that
> critical interrupts are properly supported on ppc64 booke.
> 
> Signed-off-by: Scott Wood <scottwood@freescale.com>
> Cc: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
> Cc: Wim Van Sebroeck <wim@iguana.be>
> ---
>  drivers/watchdog/booke_wdt.c | 8 --------
>  1 file changed, 8 deletions(-)
> 
> diff --git a/drivers/watchdog/booke_wdt.c b/drivers/watchdog/booke_wdt.c
> index f1b8d55..a8dbceb3 100644
> --- a/drivers/watchdog/booke_wdt.c
> +++ b/drivers/watchdog/booke_wdt.c
> @@ -138,14 +138,6 @@ static void __booke_wdt_enable(void *data)
>  	val &= ~WDTP_MASK;
>  	val |= (TCR_WIE|TCR_WRC(WRC_CHIP)|WDTP(booke_wdt_period));
>  
> -#ifdef CONFIG_PPC_BOOK3E_64
> -	/*
> -	 * Crit ints are currently broken on PPC64 Book-E, so
> -	 * just disable them for now.
> -	 */
> -	val &= ~TCR_WIE;
> -#endif
> -
>  	mtspr(SPRN_TCR, val);
>  }
>  

Patch has been added to linux-watchdog-next.

Kind regards,
Wim.

Re: [PATCH 10/10] Revert "powerpc/watchdog: Don't enable interrupt on PPC64 BookE"

[Scott Wood]

On Sat, 2014-03-15 at 20:51 +0100, Wim Van Sebroeck wrote:
> Hi Scott,
> 
> > This reverts commit 3978bdb4ed653342b0be66c031bf61b72cc55d60, now that
> > critical interrupts are properly supported on ppc64 booke.
> > 
> > Signed-off-by: Scott Wood <scottwood@freescale.com>
> > Cc: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
> > Cc: Wim Van Sebroeck <wim@iguana.be>
> > ---
> >  drivers/watchdog/booke_wdt.c | 8 --------
> >  1 file changed, 8 deletions(-)
> > 
> > diff --git a/drivers/watchdog/booke_wdt.c b/drivers/watchdog/booke_wdt.c
> > index f1b8d55..a8dbceb3 100644
> > --- a/drivers/watchdog/booke_wdt.c
> > +++ b/drivers/watchdog/booke_wdt.c
> > @@ -138,14 +138,6 @@ static void __booke_wdt_enable(void *data)
> >  	val &= ~WDTP_MASK;
> >  	val |= (TCR_WIE|TCR_WRC(WRC_CHIP)|WDTP(booke_wdt_period));
> >  
> > -#ifdef CONFIG_PPC_BOOK3E_64
> > -	/*
> > -	 * Crit ints are currently broken on PPC64 Book-E, so
> > -	 * just disable them for now.
> > -	 */
> > -	val &= ~TCR_WIE;
> > -#endif
> > -
> >  	mtspr(SPRN_TCR, val);
> >  }
> >  
> 
> Patch has been added to linux-watchdog-next.

Please unapply it.  It is patch 10/10 and depends on the previous parts
of the patchset to make critical interrupts work properly.

-Scott

Re: [PATCH 10/10] Revert "powerpc/watchdog: Don't enable interrupt on PPC64 BookE"

[Wim Van Sebroeck]

Hi Scott,

> On Sat, 2014-03-15 at 20:51 +0100, Wim Van Sebroeck wrote:
> > Hi Scott,
> > 
> > > This reverts commit 3978bdb4ed653342b0be66c031bf61b72cc55d60, now that
> > > critical interrupts are properly supported on ppc64 booke.
> > > 
> > > Signed-off-by: Scott Wood <scottwood@freescale.com>
> > > Cc: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
> > > Cc: Wim Van Sebroeck <wim@iguana.be>
> > > ---
> > >  drivers/watchdog/booke_wdt.c | 8 --------
> > >  1 file changed, 8 deletions(-)
> > > 
> > > diff --git a/drivers/watchdog/booke_wdt.c b/drivers/watchdog/booke_wdt.c
> > > index f1b8d55..a8dbceb3 100644
> > > --- a/drivers/watchdog/booke_wdt.c
> > > +++ b/drivers/watchdog/booke_wdt.c
> > > @@ -138,14 +138,6 @@ static void __booke_wdt_enable(void *data)
> > >  	val &= ~WDTP_MASK;
> > >  	val |= (TCR_WIE|TCR_WRC(WRC_CHIP)|WDTP(booke_wdt_period));
> > >  
> > > -#ifdef CONFIG_PPC_BOOK3E_64
> > > -	/*
> > > -	 * Crit ints are currently broken on PPC64 Book-E, so
> > > -	 * just disable them for now.
> > > -	 */
> > > -	val &= ~TCR_WIE;
> > > -#endif
> > > -
> > >  	mtspr(SPRN_TCR, val);
> > >  }
> > >  
> > 
> > Patch has been added to linux-watchdog-next.
> 
> Please unapply it.  It is patch 10/10 and depends on the previous parts
> of the patchset to make critical interrupts work properly.

Unapplied.

Kind regards,
Wim.

RE: [PATCH 05/10] powerpc/booke64: Use SPRG7 for VDSO

[mihai.caraman]

> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Friday, March 14, 2014 2:01 AM
> To: Benjamin Herrenschmidt
> Cc: linuxppc-dev@lists.ozlabs.org; Kumar Gala; Tiejun Chen; Wood Scott-
> B07421; Caraman Mihai Claudiu-B02008; Anton Blanchard; Paul Mackerras;
> kvm-ppc@vger.kernel.org
> Subject: [PATCH 05/10] powerpc/booke64: Use SPRG7 for VDSO
>=20
> Previously SPRG3 was marked for use by both VDSO and critical
> interrupts (though critical interrupts were not fully implemented).
>=20
> In commit 8b64a9dfb091f1eca8b7e58da82f1e7d1d5fe0ad ("powerpc/booke64:
> Use SPRG0/3 scratch for bolted TLB miss & crit int"), Mihai Caraman
> made an attempt to resolve this conflict by restoring the VDSO value
> early in the critical interrupt, but this has some issues:
>=20

>  - It forces critical exceptions to be a special case handled
>    differently from even machine check and debug level exceptions.

Yes, this was ugly.

> Since we cannot use SPRG4-7 for scratch without corrupting the state of
> a KVM guest, move VDSO to SPRG7 on book3e.

At that time I thought that information exposed through SPRN_USPRG3 is
part of the ABI which can't be changed, and this lead to complicated
gymnastic. But since VSDO's __kernel_getcpu() function hides SPRN_USPRGx
access, I think your unified approach is the right way.

-Mike

[PATCH v2 06/10] powerpc/booke64: Use SPRG_TLB_EXFRAME on bolted handlers

[Scott Wood]

While bolted handlers (including e6500) do not need to deal with a TLB
miss recursively causing another TLB miss, nested TLB misses can still
happen with crit/mc/debug exceptions -- so we still need to honor
SPRG_TLB_EXFRAME.

We don't need to spend time modifying it in the TLB miss fastpath,
though -- the special level exception will handle that.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: kvm-ppc@vger.kernel.org
---
v2: Removed accidental duplicate/misplaced write to SPRG_VDSO,
which had been in a previous version of patch 5/10.

 arch/powerpc/include/asm/exception-64e.h    | 10 -------
 arch/powerpc/include/asm/kvm_booke_hv_asm.h |  8 ++++--
 arch/powerpc/kvm/bookehv_interrupts.S       | 11 ++++++--
 arch/powerpc/mm/tlb_low_64e.S               | 44 ++++++++++++++++++-----------
 4 files changed, 42 insertions(+), 31 deletions(-)

diff --git a/arch/powerpc/include/asm/exception-64e.h b/arch/powerpc/include/asm/exception-64e.h
index e73452f..a563d9af 100644
--- a/arch/powerpc/include/asm/exception-64e.h
+++ b/arch/powerpc/include/asm/exception-64e.h
@@ -172,16 +172,6 @@ exc_##label##_book3e:
 	ld	r9,EX_TLB_R9(r12);					    \
 	ld	r8,EX_TLB_R8(r12);					    \
 	mtlr	r16;
-#define TLB_MISS_PROLOG_STATS_BOLTED						    \
-	mflr	r10;							    \
-	std	r8,PACA_EXTLB+EX_TLB_R8(r13);				    \
-	std	r9,PACA_EXTLB+EX_TLB_R9(r13);				    \
-	std	r10,PACA_EXTLB+EX_TLB_LR(r13);
-#define TLB_MISS_RESTORE_STATS_BOLTED					            \
-	ld	r16,PACA_EXTLB+EX_TLB_LR(r13);				    \
-	ld	r9,PACA_EXTLB+EX_TLB_R9(r13);				    \
-	ld	r8,PACA_EXTLB+EX_TLB_R8(r13);				    \
-	mtlr	r16;
 #define TLB_MISS_STATS_D(name)						    \
 	addi	r9,r13,MMSTAT_DSTATS+name;				    \
 	bl	.tlb_stat_inc;
diff --git a/arch/powerpc/include/asm/kvm_booke_hv_asm.h b/arch/powerpc/include/asm/kvm_booke_hv_asm.h
index c3e3fd5..e5f048b 100644
--- a/arch/powerpc/include/asm/kvm_booke_hv_asm.h
+++ b/arch/powerpc/include/asm/kvm_booke_hv_asm.h
@@ -45,10 +45,12 @@
  *
  * Expected inputs (TLB exception type):
  *  r10 = saved CR
+ *  r12 = extlb pointer
  *  r13 = PACA_POINTER
- *  *(r13 + PACA_EX##type + EX_TLB_R10) = saved r10
- *  *(r13 + PACA_EX##type + EX_TLB_R11) = saved r11
- *  SPRN_SPRG_GEN_SCRATCH = saved r13
+ *  *(r12 + EX_TLB_R10) = saved r10
+ *  *(r12 + EX_TLB_R11) = saved r11
+ *  *(r12 + EX_TLB_R13) = saved r13
+ *  SPRN_SPRG_GEN_SCRATCH = saved r12
  *
  * Only the bolted version of TLB miss exception handlers is supported now.
  */
diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S
index 99635a3..a1712b8 100644
--- a/arch/powerpc/kvm/bookehv_interrupts.S
+++ b/arch/powerpc/kvm/bookehv_interrupts.S
@@ -229,13 +229,20 @@
 	stw	r10, VCPU_CR(r4)
 	PPC_STL r11, VCPU_GPR(R4)(r4)
 	PPC_STL	r5, VCPU_GPR(R5)(r4)
-	mfspr	r5, \scratch
 	PPC_STL	r6, VCPU_GPR(R6)(r4)
 	PPC_STL	r8, VCPU_GPR(R8)(r4)
 	PPC_STL	r9, VCPU_GPR(R9)(r4)
-	PPC_STL r5, VCPU_GPR(R13)(r4)
+	.if \type == EX_TLB
+	PPC_LL	r5, EX_TLB_R13(r12)
+	PPC_LL	r6, EX_TLB_R10(r12)
+	PPC_LL	r8, EX_TLB_R11(r12)
+	mfspr	r12, \scratch
+	.else
+	mfspr	r5, \scratch
 	PPC_LL	r6, (\paca_ex + \ex_r10)(r13)
 	PPC_LL	r8, (\paca_ex + \ex_r11)(r13)
+	.endif
+	PPC_STL r5, VCPU_GPR(R13)(r4)
 	PPC_STL r3, VCPU_GPR(R3)(r4)
 	PPC_STL r7, VCPU_GPR(R7)(r4)
 	PPC_STL r12, VCPU_GPR(R12)(r4)
diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S
index 1e50249..356e8b4 100644
--- a/arch/powerpc/mm/tlb_low_64e.S
+++ b/arch/powerpc/mm/tlb_low_64e.S
@@ -39,37 +39,49 @@
  *                                                                    *
  **********************************************************************/
 
+/*
+ * Note that, unlike non-bolted handlers, TLB_EXFRAME is not
+ * modified by the TLB miss handlers themselves, since the TLB miss
+ * handler code will not itself cause a recursive TLB miss.
+ *
+ * TLB_EXFRAME will be modified when crit/mc/debug exceptions are
+ * entered/exited.
+ */
 .macro tlb_prolog_bolted intnum addr
-	mtspr	SPRN_SPRG_GEN_SCRATCH,r13
+	mtspr	SPRN_SPRG_GEN_SCRATCH,r12
+	mfspr	r12,SPRN_SPRG_TLB_EXFRAME
+	std	r13,EX_TLB_R13(r12)
+	std	r10,EX_TLB_R10(r12)
 	mfspr	r13,SPRN_SPRG_PACA
-	std	r10,PACA_EXTLB+EX_TLB_R10(r13)
+
 	mfcr	r10
-	std	r11,PACA_EXTLB+EX_TLB_R11(r13)
+	std	r11,EX_TLB_R11(r12)
 #ifdef CONFIG_KVM_BOOKE_HV
 BEGIN_FTR_SECTION
 	mfspr	r11, SPRN_SRR1
 END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
 #endif
 	DO_KVM	\intnum, SPRN_SRR1
-	std	r16,PACA_EXTLB+EX_TLB_R16(r13)
+	std	r16,EX_TLB_R16(r12)
 	mfspr	r16,\addr		/* get faulting address */
-	std	r14,PACA_EXTLB+EX_TLB_R14(r13)
+	std	r14,EX_TLB_R14(r12)
 	ld	r14,PACAPGD(r13)
-	std	r15,PACA_EXTLB+EX_TLB_R15(r13)
-	std	r10,PACA_EXTLB+EX_TLB_CR(r13)
-	TLB_MISS_PROLOG_STATS_BOLTED
+	std	r15,EX_TLB_R15(r12)
+	std	r10,EX_TLB_CR(r12)
+	TLB_MISS_PROLOG_STATS
 .endm
 
 .macro tlb_epilog_bolted
-	ld	r14,PACA_EXTLB+EX_TLB_CR(r13)
-	ld	r10,PACA_EXTLB+EX_TLB_R10(r13)
-	ld	r11,PACA_EXTLB+EX_TLB_R11(r13)
+	ld	r14,EX_TLB_CR(r12)
+	ld	r10,EX_TLB_R10(r12)
+	ld	r11,EX_TLB_R11(r12)
+	ld	r13,EX_TLB_R13(r12)
 	mtcr	r14
-	ld	r14,PACA_EXTLB+EX_TLB_R14(r13)
-	ld	r15,PACA_EXTLB+EX_TLB_R15(r13)
-	TLB_MISS_RESTORE_STATS_BOLTED
-	ld	r16,PACA_EXTLB+EX_TLB_R16(r13)
-	mfspr	r13,SPRN_SPRG_GEN_SCRATCH
+	ld	r14,EX_TLB_R14(r12)
+	ld	r15,EX_TLB_R15(r12)
+	TLB_MISS_RESTORE_STATS
+	ld	r16,EX_TLB_R16(r12)
+	mfspr	r12,SPRN_SPRG_GEN_SCRATCH
 .endm
 
 /* Data TLB miss */
-- 
1.8.3.2