powerpc/mpc5200: Disable bestcomm prefetching when ATA DMA enabled

When ATA DMA is enabled, bestcomm prefetching does not work.  This
patch adds a function to disable bestcomm prefetch when the ATA
Bestcomm task is initialized.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/powerpc/sysdev/bestcomm/ata.c b/arch/powerpc/sysdev/bestcomm/ata.c
index 1f5258fb38c3..901c9f91e5dd 100644
--- a/arch/powerpc/sysdev/bestcomm/ata.c
+++ b/arch/powerpc/sysdev/bestcomm/ata.c
@@ -61,6 +61,9 @@ bcom_ata_init(int queue_len, int maxbufsize)
         struct bcom_ata_var *var;
         struct bcom_ata_inc *inc;
 
+        /* Prefetch breaks ATA DMA.  Turn it off for ATA DMA */
+        bcom_disable_prefetch();
+
         tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_ata_bd), 0);
         if (!tsk)
                 return NULL;