[CELL] spufs: Avoid unexpectedly restaring MFC during context save
The current SPU context saving procedure in SPUFS unexpectedly
restarts MFC when halting decrementer, because MFC_CNTL[Dh] is set
without MFC_CNTL[Sm]. This bug causes, for example, saving broken DMA
queues. Here is a patch to fix the problem.
Signed-off-by: Kazunori Asayama <asayama@sm.sony.co.jp>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
diff --git a/arch/powerpc/platforms/cell/spufs/switch.c b/arch/powerpc/platforms/cell/spufs/switch.c
index 9c506ba..827aada 100644
--- a/arch/powerpc/platforms/cell/spufs/switch.c
+++ b/arch/powerpc/platforms/cell/spufs/switch.c
@@ -271,7 +271,8 @@
* Write MFC_CNTL[Dh] set to a '1' to halt
* the decrementer.
*/
- out_be64(&priv2->mfc_control_RW, MFC_CNTL_DECREMENTER_HALTED);
+ out_be64(&priv2->mfc_control_RW,
+ MFC_CNTL_DECREMENTER_HALTED | MFC_CNTL_SUSPEND_MASK);
eieio();
}
diff --git a/include/asm-powerpc/spu.h b/include/asm-powerpc/spu.h
index 42d88a6..a034f03 100644
--- a/include/asm-powerpc/spu.h
+++ b/include/asm-powerpc/spu.h
@@ -411,6 +411,7 @@
#define MFC_CNTL_RESUME_DMA_QUEUE (0ull << 0)
#define MFC_CNTL_SUSPEND_DMA_QUEUE (1ull << 0)
#define MFC_CNTL_SUSPEND_DMA_QUEUE_MASK (1ull << 0)
+#define MFC_CNTL_SUSPEND_MASK (1ull << 4)
#define MFC_CNTL_NORMAL_DMA_QUEUE_OPERATION (0ull << 8)
#define MFC_CNTL_SUSPEND_IN_PROGRESS (1ull << 8)
#define MFC_CNTL_SUSPEND_COMPLETE (3ull << 8)