From 7fc7864a44e4d8eff94fcb403eff5aafa4e48dcc Mon Sep 17 00:00:00 2001
From: Luke Browning <lukebr@linux.vnet.ibm.com>
Date: Mon, 28 Apr 2008 17:35:56 +1000
Subject: [PATCH] --- yaml --- r: 96245 b: refs/heads/master c:
 de1028927ae3487e2e450dacf50fbf32042aee18 h: refs/heads/master i:   96243:
 2d4b16d12da5e5e2167e05e602472028beb947ed v: v3

---
 [refs]                                        |  2 +-
 trunk/arch/powerpc/platforms/cell/spu_base.c  |  4 ++++
 .../powerpc/platforms/cell/spufs/switch.c     | 23 +++++++++++--------
 trunk/include/asm-powerpc/spu.h               |  1 +
 4 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/[refs] b/[refs]
index 5405e28043e3..9f503fbac3b7 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f3d69e0507f84903059d456c5d19f10b2df3ac69
+refs/heads/master: de1028927ae3487e2e450dacf50fbf32042aee18
diff --git a/trunk/arch/powerpc/platforms/cell/spu_base.c b/trunk/arch/powerpc/platforms/cell/spu_base.c
index b9ae675640d0..70c660121ec4 100644
--- a/trunk/arch/powerpc/platforms/cell/spu_base.c
+++ b/trunk/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/trunk/arch/powerpc/platforms/cell/spufs/switch.c b/trunk/arch/powerpc/platforms/cell/spufs/switch.c
index 47c658051fcb..3df9a36eb2f5 100644
--- a/trunk/arch/powerpc/platforms/cell/spufs/switch.c
+++ b/trunk/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/trunk/include/asm-powerpc/spu.h b/trunk/include/asm-powerpc/spu.h
index 882aa953968a..6abead6e681a 100644
--- a/trunk/include/asm-powerpc/spu.h
+++ b/trunk/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;