powerpc/spufs: remove class_0_dsisr from spu exception handling

According to the CBEA, the SPU dsisr is not updated for class 0
exceptions.

spu_stopped() is testing the dsisr that was passed to it from the class
0 exception handler, so we return a false positive here.

This patch cleans up the interrupt handler and erroneous tests in
spu_stopped. It also removes the fields from the csa since it is not
needed to process class 0 events.

Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

arch/powerpc/platforms/cell/spu_base.c

@@ -324,14 +324,12 @@ spu_irq_class_0(int irq, void *data)
 	stat = spu_int_stat_get(spu, 0) & mask;
 
 	spu->class_0_pending |= stat;
-	spu->class_0_dsisr = spu_mfc_dsisr_get(spu);
 	spu->class_0_dar = spu_mfc_dar_get(spu);
 	spin_unlock(&spu->register_lock);
 
 	spu->stop_callback(spu, 0);
 
 	spu->class_0_pending = 0;
-	spu->class_0_dsisr = 0;
 	spu->class_0_dar = 0;
 
 	spu_int_stat_clear(spu, 0, stat);

arch/powerpc/platforms/cell/spufs/run.c

@@ -27,7 +27,6 @@ void spufs_stop_callback(struct spu *spu, int irq)
 		switch(irq) {
 		case 0 :
 			ctx->csa.class_0_pending = spu->class_0_pending;
-			ctx->csa.class_0_dsisr = spu->class_0_dsisr;
 			ctx->csa.class_0_dar = spu->class_0_dar;
 			break;
 		case 1 :
@@ -69,10 +68,6 @@ top:
 	if (test_bit(SPU_SCHED_NOTIFY_ACTIVE, &ctx->sched_flags))
 		return 1;
 
-	dsisr = ctx->csa.class_0_dsisr;
-	if (dsisr & (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED))
-		return 1;
-
 	dsisr = ctx->csa.class_1_dsisr;
 	if (dsisr & (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED))
 		return 1;

arch/powerpc/xmon/xmon.c

@@ -2844,7 +2844,6 @@ static void dump_spu_fields(struct spu *spu)
 	DUMP_FIELD(spu, "0x%lx", flags);
 	DUMP_FIELD(spu, "%d", class_0_pending);
 	DUMP_FIELD(spu, "0x%lx", class_0_dar);
-	DUMP_FIELD(spu, "0x%lx", class_0_dsisr);
 	DUMP_FIELD(spu, "0x%lx", class_1_dar);
 	DUMP_FIELD(spu, "0x%lx", class_1_dsisr);
 	DUMP_FIELD(spu, "0x%lx", irqs[0]);

include/asm-powerpc/spu.h

@@ -131,7 +131,6 @@ struct spu {
 	u64 flags;
 	u64 class_0_pending;
 	u64 class_0_dar;
-	u64 class_0_dsisr;
 	u64 class_1_dar;
 	u64 class_1_dsisr;
 	size_t ls_size;

include/asm-powerpc/spu_csa.h

@@ -254,7 +254,7 @@ struct spu_state {
 	u64 spu_chnldata_RW[32];
 	u32 spu_mailbox_data[4];
 	u32 pu_mailbox_data[1];
-	u64 class_0_dar, class_0_dsisr, class_0_pending;
+	u64 class_0_dar, class_0_pending;
 	u64 class_1_dar, class_1_dsisr;
 	unsigned long suspend_time;
 	spinlock_t register_lock;