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

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

1 files changed, 34 insertions, 22 deletions

diff --git a/arch/sparc64/kernel/irq.c b/arch/sparc64/kernel/irq.c
index 4db4dd576210..26cdf47981c3 100644
--- a/arch/sparc64/kernel/irq.c
+++ b/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();