[PATCH] IOAT: ioatdma needs to to play nice in a multi-dma-client world
From: Shannon Nelson <hidden>
Date: 2007-08-23 00:12:50
Now that the DMA engine has a multi-client interface, fix the ioatdma driver to play along. At the same time, remove a couple of unnecessary reads and writes. Signed-off-by: Shannon Nelson <redacted> --- drivers/dma/ioatdma.c | 18 ++++-------------- 1 files changed, 4 insertions(+), 14 deletions(-)
diff --git a/drivers/dma/ioatdma.c b/drivers/dma/ioatdma.c
index 2d1f178..41b18c5 100644
--- a/drivers/dma/ioatdma.c
+++ b/drivers/dma/ioatdma.c@@ -191,17 +191,12 @@ static int ioat_dma_alloc_chan_resources(struct dma_chan *chan) int i; LIST_HEAD(tmp_list); - /* - * In-use bit automatically set by reading chanctrl - * If 0, we got it, if 1, someone else did - */ - chanctrl = readw(ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET); - if (chanctrl & IOAT_CHANCTRL_CHANNEL_IN_USE) - return -EBUSY; + /* have we already been set up? */ + if (!list_empty(&ioat_chan->free_desc)) + return INITIAL_IOAT_DESC_COUNT; /* Setup register to interrupt and write completion status on error */ - chanctrl = IOAT_CHANCTRL_CHANNEL_IN_USE | - IOAT_CHANCTRL_ERR_INT_EN | + chanctrl = IOAT_CHANCTRL_ERR_INT_EN | IOAT_CHANCTRL_ANY_ERR_ABORT_EN | IOAT_CHANCTRL_ERR_COMPLETION_EN; writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
@@ -282,11 +277,6 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan) in_use_descs - 1); ioat_chan->last_completion = ioat_chan->completion_addr = 0; - - /* Tell hw the chan is free */ - chanctrl = readw(ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET); - chanctrl &= ~IOAT_CHANCTRL_CHANNEL_IN_USE; - writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET); } static struct dma_async_tx_descriptor *