[SPARC64]: Access ivector_table[] using physical addresses.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/kernel/entry.S

@@ -429,16 +429,16 @@ do_ivec:
 	stxa		%g0, [%g0] ASI_INTR_RECEIVE
 	membar		#Sync
 
-	sethi		%hi(ivector_table), %g2
+	sethi		%hi(ivector_table_pa), %g2
+	ldx		[%g2 + %lo(ivector_table_pa)], %g2
 	sllx		%g3, 4, %g3
-	or		%g2, %lo(ivector_table), %g2
 	add		%g2, %g3, %g3
 
-	TRAP_LOAD_IRQ_WORK(%g6, %g1)
+	TRAP_LOAD_IRQ_WORK_PA(%g6, %g1)
 
-	ldx		[%g6], %g5		/* g5 = irq_work(cpu) */
-	stx		%g5, [%g3 + 0x00]	/* bucket->irq_chain = g5 */
-	stx		%g3, [%g6]		/* irq_work(cpu) = bucket */
+	ldx		[%g6], %g5
+	stxa		%g5, [%g3] ASI_PHYS_USE_EC
+	stx		%g3, [%g6]
 	wr		%g0, 1 << PIL_DEVICE_IRQ, %set_softint
 	retry
 do_ivec_xcall:

arch/sparc64/kernel/irq.c

@@ -51,15 +51,12 @@
  * To make processing these packets efficient and race free we use
  * an array of irq buckets below.  The interrupt vector handler in
  * entry.S feeds incoming packets into per-cpu pil-indexed lists.
- * The IVEC handler does not need to act atomically, the PIL dispatch
- * code uses CAS to get an atomic snapshot of the list and clear it
- * at the same time.
  *
  * If you make changes to ino_bucket, please update hand coded assembler
  * of the vectored interrupt trap handler(s) in entry.S and sun4v_ivec.S
  */
 struct ino_bucket {
-/*0x00*/unsigned long irq_chain;
+/*0x00*/unsigned long irq_chain_pa;
 
 	/* Virtual interrupt number assigned to this INO.  */
 /*0x08*/unsigned int virt_irq;
@@ -68,20 +65,14 @@ struct ino_bucket {
 
 #define NUM_IVECS	(IMAP_INR + 1)
 struct ino_bucket ivector_table[NUM_IVECS] __attribute__ ((aligned (SMP_CACHE_BYTES)));
+unsigned long ivector_table_pa;
 
 #define __irq_ino(irq) \
         (((struct ino_bucket *)(irq)) - &ivector_table[0])
 #define __bucket(irq) ((struct ino_bucket *)(irq))
 #define __irq(bucket) ((unsigned long)(bucket))
 
-/* This has to be in the main kernel image, it cannot be
- * turned into per-cpu data.  The reason is that the main
- * kernel image is locked into the TLB and this structure
- * is accessed from the vectored interrupt trap handler.  If
- * access to this structure takes a TLB miss it could cause
- * the 5-level sparc v9 trap stack to overflow.
- */
-#define irq_work(__cpu)	&(trap_block[(__cpu)].irq_worklist)
+#define irq_work_pa(__cpu)	&(trap_block[(__cpu)].irq_worklist_pa)
 
 static struct {
 	unsigned long irq;
@@ -689,9 +680,8 @@ void ack_bad_irq(unsigned int virt_irq)
 
 void handler_irq(int irq, struct pt_regs *regs)
 {
-	struct ino_bucket *bucket;
+	unsigned long pstate, bucket_pa;
 	struct pt_regs *old_regs;
-	unsigned long pstate;
 
 	clear_softint(1 << irq);
 
@@ -704,18 +694,30 @@ void handler_irq(int irq, struct pt_regs *regs)
 			     "ldx	[%2], %1\n\t"
 			     "stx	%%g0, [%2]\n\t"
 			     "wrpr	%0, 0x0, %%pstate\n\t"
-			     : "=&r" (pstate), "=&r" (bucket)
-			     : "r" (irq_work(smp_processor_id())),
+			     : "=&r" (pstate), "=&r" (bucket_pa)
+			     : "r" (irq_work_pa(smp_processor_id())),
 			       "i" (PSTATE_IE)
 			     : "memory");
 
-	while (bucket) {
-		struct ino_bucket *next = __bucket(bucket->irq_chain);
+	while (bucket_pa) {
+		unsigned long next_pa;
+		unsigned int virt_irq;
 
-		bucket->irq_chain = 0UL;
-		__do_IRQ(bucket->virt_irq);
+		__asm__ __volatile__("ldxa	[%2] %4, %0\n\t"
+				     "lduwa	[%3] %4, %1\n\t"
+				     "stxa	%%g0, [%2] %4"
+				     : "=&r" (next_pa), "=&r" (virt_irq)
+				     : "r" (bucket_pa +
+					    offsetof(struct ino_bucket,
+						     irq_chain_pa)),
+				       "r" (bucket_pa +
+					    offsetof(struct ino_bucket,
+						     virt_irq)),
+				       "i" (ASI_PHYS_USE_EC));
 
-		bucket = next;
+		__do_IRQ(virt_irq);
+
+		bucket_pa = next_pa;
 	}
 
 	irq_exit();
@@ -815,7 +817,7 @@ void init_irqwork_curcpu(void)
 {
 	int cpu = hard_smp_processor_id();
 
-	trap_block[cpu].irq_worklist = 0UL;
+	trap_block[cpu].irq_worklist_pa = 0UL;
 }
 
 /* Please be very careful with register_one_mondo() and
@@ -926,6 +928,14 @@ static struct irqaction timer_irq_action = {
 	.name = "timer",
 };
 
+/* XXX Belongs in a common location. XXX */
+static unsigned long kimage_addr_to_ra(void *p)
+{
+	unsigned long val = (unsigned long) p;
+
+	return kern_base + (val - KERNBASE);
+}
+
 /* Only invoked on boot processor. */
 void __init init_IRQ(void)
 {
@@ -933,6 +943,8 @@ void __init init_IRQ(void)
 	kill_prom_timer();
 	memset(&ivector_table[0], 0, sizeof(ivector_table));
 
+	ivector_table_pa = kimage_addr_to_ra(&ivector_table[0]);
+
 	if (tlb_type == hypervisor)
 		sun4v_init_mondo_queues();
 

arch/sparc64/kernel/sun4v_ivec.S

@@ -96,19 +96,17 @@ sun4v_dev_mondo:
 	stxa	%g2, [%g4] ASI_QUEUE
 	membar	#Sync
 
-	/* Get &__irq_work[smp_processor_id()] into %g1.  */
-	TRAP_LOAD_IRQ_WORK(%g1, %g4)
+	TRAP_LOAD_IRQ_WORK_PA(%g1, %g4)
 
-	/* Get &ivector_table[IVEC] into %g4.  */
-	sethi	%hi(ivector_table), %g4
+	/* Get __pa(&ivector_table[IVEC]) into %g4.  */
+	sethi	%hi(ivector_table_pa), %g4
+	ldx	[%g4 + %lo(ivector_table_pa)], %g4
 	sllx	%g3, 4, %g3
-	or	%g4, %lo(ivector_table), %g4
 	add	%g4, %g3, %g4
 
-	/* Insert ivector_table[] entry into __irq_work[] queue.  */
-	ldx	[%g1], %g2		/* g2 = irq_work(cpu) */
-	stx	%g2, [%g4 + 0x00]	/* bucket->irq_chain = g2 */
-	stx	%g4, [%g1]		/* irq_work(cpu) = bucket */
+	ldx	[%g1], %g2
+	stxa	%g2, [%g4] ASI_PHYS_USE_EC
+	stx	%g4, [%g1]
 
 	/* Signal the interrupt by setting (1 << pil) in %softint.  */
 	wr	%g0, 1 << PIL_DEVICE_IRQ, %set_softint

arch/sparc64/kernel/traps.c

@@ -2569,8 +2569,8 @@ void __init trap_init(void)
 	     offsetof(struct trap_per_cpu, tsb_huge)) ||
 	    (TRAP_PER_CPU_TSB_HUGE_TEMP !=
 	     offsetof(struct trap_per_cpu, tsb_huge_temp)) ||
-	    (TRAP_PER_CPU_IRQ_WORKLIST !=
-	     offsetof(struct trap_per_cpu, irq_worklist)) ||
+	    (TRAP_PER_CPU_IRQ_WORKLIST_PA !=
+	     offsetof(struct trap_per_cpu, irq_worklist_pa)) ||
 	    (TRAP_PER_CPU_CPU_MONDO_QMASK !=
 	     offsetof(struct trap_per_cpu, cpu_mondo_qmask)) ||
 	    (TRAP_PER_CPU_DEV_MONDO_QMASK !=

include/asm-sparc64/cpudata.h

@@ -75,7 +75,7 @@ struct trap_per_cpu {
 	unsigned long		tsb_huge_temp;
 
 /* Dcache line 8: IRQ work list, and keep trap_block a power-of-2 in size.  */
-	unsigned long		irq_worklist;
+	unsigned long		irq_worklist_pa;
 	unsigned int		cpu_mondo_qmask;
 	unsigned int		dev_mondo_qmask;
 	unsigned int		resum_qmask;
@@ -127,7 +127,7 @@ extern struct sun4v_2insn_patch_entry __sun4v_2insn_patch,
 #define TRAP_PER_CPU_CPU_LIST_PA	0xc8
 #define TRAP_PER_CPU_TSB_HUGE		0xd0
 #define TRAP_PER_CPU_TSB_HUGE_TEMP	0xd8
-#define TRAP_PER_CPU_IRQ_WORKLIST	0xe0
+#define TRAP_PER_CPU_IRQ_WORKLIST_PA	0xe0
 #define TRAP_PER_CPU_CPU_MONDO_QMASK	0xe8
 #define TRAP_PER_CPU_DEV_MONDO_QMASK	0xec
 #define TRAP_PER_CPU_RESUM_QMASK	0xf0
@@ -183,9 +183,9 @@ extern struct sun4v_2insn_patch_entry __sun4v_2insn_patch,
 	ldx	[DEST + TRAP_PER_CPU_PGD_PADDR], DEST;
 
 /* Clobbers TMP, loads local processor's IRQ work area into DEST.  */
-#define TRAP_LOAD_IRQ_WORK(DEST, TMP)		\
+#define TRAP_LOAD_IRQ_WORK_PA(DEST, TMP)	\
 	TRAP_LOAD_TRAP_BLOCK(DEST, TMP)		\
-	add	DEST, TRAP_PER_CPU_IRQ_WORKLIST, DEST;
+	add	DEST, TRAP_PER_CPU_IRQ_WORKLIST_PA, DEST;
 
 /* Clobbers TMP, loads DEST with current thread info pointer.  */
 #define TRAP_LOAD_THREAD_REG(DEST, TMP)		\
@@ -222,9 +222,9 @@ extern struct sun4v_2insn_patch_entry __sun4v_2insn_patch,
 	ldx	[DEST + TRAP_PER_CPU_PGD_PADDR], DEST;
 
 /* Clobbers TMP, loads local processor's IRQ work area into DEST.  */
-#define TRAP_LOAD_IRQ_WORK(DEST, TMP)		\
+#define TRAP_LOAD_IRQ_WORK_PA(DEST, TMP)	\
 	TRAP_LOAD_TRAP_BLOCK(DEST, TMP)		\
-	add	DEST, TRAP_PER_CPU_IRQ_WORKLIST, DEST;
+	add	DEST, TRAP_PER_CPU_IRQ_WORKLIST_PA, DEST;
 
 #define TRAP_LOAD_THREAD_REG(DEST, TMP)		\
 	TRAP_LOAD_TRAP_BLOCK(DEST, TMP)		\