3 files changed, 19 insertions, 9 deletions

diff --git a/arch/powerpc/platforms/cell/spu_base.c b/arch/powerpc/platforms/cell/spu_base.c
index b9ae675640d0..70c660121ec4 100644
--- a/arch/powerpc/platforms/cell/spu_base.c
+++ b/arch/powerpc/platforms/cell/spu_base.c
@@ -141,6 +141,10 @@ static void spu_restart_dma(struct spu *spu)
 
         if (!test_bit(SPU_CONTEXT_SWITCH_PENDING, &spu->flags))
                 out_be64(&priv2->mfc_control_RW, MFC_CNTL_RESTART_DMA_COMMAND);
+        else {
+                set_bit(SPU_CONTEXT_FAULT_PENDING, &spu->flags);
+                mb();
+        }
 }
 
 static inline void spu_load_slb(struct spu *spu, int slbe, struct spu_slb *slb)
diff --git a/arch/powerpc/platforms/cell/spufs/switch.c b/arch/powerpc/platforms/cell/spufs/switch.c
index 47c658051fcb..3df9a36eb2f5 100644
--- a/arch/powerpc/platforms/cell/spufs/switch.c
+++ b/arch/powerpc/platforms/cell/spufs/switch.c
@@ -139,6 +139,7 @@ static inline void disable_interrupts(struct spu_state *csa, struct spu *spu)
          * via a simple load.
          */
         set_bit(SPU_CONTEXT_SWITCH_PENDING, &spu->flags);
+        clear_bit(SPU_CONTEXT_FAULT_PENDING, &spu->flags);
         synchronize_irq(spu->irqs[0]);
         synchronize_irq(spu->irqs[1]);
         synchronize_irq(spu->irqs[2]);
@@ -739,10 +740,14 @@ static inline void set_switch_active(struct spu_state *csa, struct spu *spu)
         /* Save, Step 48:
          * Restore, Step 23.
          *     Change the software context switch pending flag
-         *     to context switch active.
+         *     to context switch active.  This implementation does
+         *     not uses a switch active flag.
          *
-         *     This implementation does not uses a switch active flag.
+         * Now that we have saved the mfc in the csa, we can add in the
+         * restart command if an exception occurred.
          */
+        if (test_bit(SPU_CONTEXT_FAULT_PENDING, &spu->flags))
+                csa->priv2.mfc_control_RW |= MFC_CNTL_RESTART_DMA_COMMAND;
         clear_bit(SPU_CONTEXT_SWITCH_PENDING, &spu->flags);
         mb();
 }
@@ -1742,15 +1747,15 @@ static inline void restore_mfc_cntl(struct spu_state *csa, struct spu *spu)
          */
         out_be64(&priv2->mfc_control_RW, csa->priv2.mfc_control_RW);
         eieio();
+
         /*
-         * FIXME: this is to restart a DMA that we were processing
-         *        before the save. better remember the fault information
-         *        in the csa instead.
+         * The queue is put back into the same state that was evident prior to
+         * the context switch. The suspend flag is added to the saved state in
+         * the csa, if the operational state was suspending or suspended. In
+         * this case, the code that suspended the mfc is responsible for
+         * continuing it. Note that SPE faults do not change the operational
+         * state of the spu.
          */
-        if ((csa->priv2.mfc_control_RW & MFC_CNTL_SUSPEND_DMA_QUEUE_MASK)) {
-                out_be64(&priv2->mfc_control_RW, MFC_CNTL_RESTART_DMA_COMMAND);
-                eieio();
-        }
 }
 
 static inline void enable_user_access(struct spu_state *csa, struct spu *spu)
diff --git a/include/asm-powerpc/spu.h b/include/asm-powerpc/spu.h
index 882aa953968a..6abead6e681a 100644
--- a/include/asm-powerpc/spu.h
+++ b/include/asm-powerpc/spu.h
@@ -100,6 +100,7 @@
 
 /* Flag indicating progress during context switch. */
 #define SPU_CONTEXT_SWITCH_PENDING      0UL
+#define SPU_CONTEXT_FAULT_PENDING       1UL
 
 struct spu_context;
 struct spu_runqueue;