fsldma: use PCI Read Multiple command

[deliverable/linux.git] / drivers / dma / fsldma.c

diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index f18d1bde04397178dfd4a88f263c77546449c381..a1cb25e277b503007dd043e096c913b8b8437cef 100644 (file)
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -12,6 +12,11 @@
  *   also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc.
  *   The support for MPC8349 DMA contorller is also added.
  *
+ * This driver instructs the DMA controller to issue the PCI Read Multiple
+ * command for PCI read operations, instead of using the default PCI Read Line
+ * command. Please be aware that this setting may result in read pre-fetching
+ * on some platforms.
+ *
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
@@ -49,9 +54,10 @@ static void dma_init(struct fsl_dma_chan *fsl_chan)
        case FSL_DMA_IP_83XX:
                /* Set the channel to below modes:
                 * EOTIE - End-of-transfer interrupt enable
+                * PRC_RM - PCI read multiple
                 */
-               DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE,
-                               32);
+               DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE
+                               | FSL_DMA_MR_PRC_RM, 32);
                break;
        }