dmaengine: xgene-dma: Fix overwritting DMA tx ring
This patch fixes an over flow issue with the TX ring descriptor. Each
descriptor is 32B in size and an operation requires 2 of these
descriptors.
Signed-off-by: Rameshwar Prasad Sahu <rsahu@apm.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/xgene-dma.c b/drivers/dma/xgene-dma.c
index 4c5ddda..8d57b1b 100644
--- a/drivers/dma/xgene-dma.c
+++ b/drivers/dma/xgene-dma.c
@@ -59,7 +59,6 @@
#define XGENE_DMA_RING_MEM_RAM_SHUTDOWN 0xD070
#define XGENE_DMA_RING_BLK_MEM_RDY 0xD074
#define XGENE_DMA_RING_BLK_MEM_RDY_VAL 0xFFFFFFFF
-#define XGENE_DMA_RING_DESC_CNT(v) (((v) & 0x0001FFFE) >> 1)
#define XGENE_DMA_RING_ID_GET(owner, num) (((owner) << 6) | (num))
#define XGENE_DMA_RING_DST_ID(v) ((1 << 10) | (v))
#define XGENE_DMA_RING_CMD_OFFSET 0x2C
@@ -379,14 +378,6 @@
return flyby_type[src_cnt];
}
-static u32 xgene_dma_ring_desc_cnt(struct xgene_dma_ring *ring)
-{
- u32 __iomem *cmd_base = ring->cmd_base;
- u32 ring_state = ioread32(&cmd_base[1]);
-
- return XGENE_DMA_RING_DESC_CNT(ring_state);
-}
-
static void xgene_dma_set_src_buffer(__le64 *ext8, size_t *len,
dma_addr_t *paddr)
{
@@ -659,15 +650,12 @@
dma_pool_free(chan->desc_pool, desc, desc->tx.phys);
}
-static int xgene_chan_xfer_request(struct xgene_dma_ring *ring,
- struct xgene_dma_desc_sw *desc_sw)
+static void xgene_chan_xfer_request(struct xgene_dma_chan *chan,
+ struct xgene_dma_desc_sw *desc_sw)
{
+ struct xgene_dma_ring *ring = &chan->tx_ring;
struct xgene_dma_desc_hw *desc_hw;
- /* Check if can push more descriptor to hw for execution */
- if (xgene_dma_ring_desc_cnt(ring) > (ring->slots - 2))
- return -EBUSY;
-
/* Get hw descriptor from DMA tx ring */
desc_hw = &ring->desc_hw[ring->head];
@@ -694,11 +682,13 @@
memcpy(desc_hw, &desc_sw->desc2, sizeof(*desc_hw));
}
+ /* Increment the pending transaction count */
+ chan->pending += ((desc_sw->flags &
+ XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
+
/* Notify the hw that we have descriptor ready for execution */
iowrite32((desc_sw->flags & XGENE_DMA_FLAG_64B_DESC) ?
2 : 1, ring->cmd);
-
- return 0;
}
/**
@@ -710,7 +700,6 @@
static void xgene_chan_xfer_ld_pending(struct xgene_dma_chan *chan)
{
struct xgene_dma_desc_sw *desc_sw, *_desc_sw;
- int ret;
/*
* If the list of pending descriptors is empty, then we
@@ -735,18 +724,13 @@
if (chan->pending >= chan->max_outstanding)
return;
- ret = xgene_chan_xfer_request(&chan->tx_ring, desc_sw);
- if (ret)
- return;
+ xgene_chan_xfer_request(chan, desc_sw);
/*
* Delete this element from ld pending queue and append it to
* ld running queue
*/
list_move_tail(&desc_sw->node, &chan->ld_running);
-
- /* Increment the pending transaction count */
- chan->pending++;
}
}
@@ -821,7 +805,8 @@
* Decrement the pending transaction count
* as we have processed one
*/
- chan->pending--;
+ chan->pending -= ((desc_sw->flags &
+ XGENE_DMA_FLAG_64B_DESC) ? 2 : 1);
/*
* Delete this node from ld running queue and append it to
@@ -1485,7 +1470,7 @@
tx_ring->id, tx_ring->num, tx_ring->desc_vaddr);
/* Set the max outstanding request possible to this channel */
- chan->max_outstanding = rx_ring->slots;
+ chan->max_outstanding = tx_ring->slots;
return ret;
}