diff --git a/drivers/rapidio/devices/tsi721.h b/drivers/rapidio/devices/tsi721.h
index 7061ac0ad4287c0d84edb39058ef6abc295e43ce..0305675270ee53ef168c15f5c93db0d06a1df87c 100644
--- a/drivers/rapidio/devices/tsi721.h
+++ b/drivers/rapidio/devices/tsi721.h
@@ -644,6 +644,9 @@ enum tsi721_smsg_int_flag {
#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+#define TSI721_BDMA_BD_RING_SZ 128
+#define TSI721_BDMA_MAX_BCOUNT (TSI721_DMAD_BCOUNT1 + 1)
+
struct tsi721_tx_desc {
struct dma_async_tx_descriptor txd;
struct tsi721_dma_desc *hw_desc;
@@ -652,6 +655,7 @@ struct tsi721_tx_desc {
u64 rio_addr;
/* upper 2-bits of 66-bit RIO address */
u8 rio_addr_u;
+ u32 bcount;
bool interrupt;
struct list_head desc_node;
struct list_head tx_list;
diff --git a/drivers/rapidio/devices/tsi721_dma.c b/drivers/rapidio/devices/tsi721_dma.c
index 91245f5dbe81a7d235f13a2dd2edbe741508d584..9b60b1f3261c1182e2c799e2affaf7e49605015c 100644
--- a/drivers/rapidio/devices/tsi721_dma.c
+++ b/drivers/rapidio/devices/tsi721_dma.c
@@ -304,35 +304,17 @@ struct tsi721_tx_desc *tsi721_desc_get(struct tsi721_bdma_chan *bdma_chan)
}
static int
-tsi721_fill_desc(struct tsi721_bdma_chan *bdma_chan,
- struct tsi721_tx_desc *desc, struct scatterlist *sg,
+tsi721_desc_fill_init(struct tsi721_tx_desc *desc, struct scatterlist *sg,
enum dma_rtype rtype, u32 sys_size)
{
struct tsi721_dma_desc *bd_ptr = desc->hw_desc;
u64 rio_addr;
- if (sg_dma_len(sg) > TSI721_DMAD_BCOUNT1 + 1) {
- dev_err(bdma_chan->dchan.device->dev,
- "SG element is too large\n");
- return -EINVAL;
- }
-
- dev_dbg(bdma_chan->dchan.device->dev,
- "desc: 0x%llx, addr: 0x%llx len: 0x%x\n",
- (u64)desc->txd.phys, (unsigned long long)sg_dma_address(sg),
- sg_dma_len(sg));
-
- dev_dbg(bdma_chan->dchan.device->dev,
- "bd_ptr = %p did=%d raddr=0x%llx\n",
- bd_ptr, desc->destid, desc->rio_addr);
-
/* Initialize DMA descriptor */
bd_ptr->type_id = cpu_to_le32((DTYPE1 << 29) |
(rtype << 19) | desc->destid);
- if (desc->interrupt)
- bd_ptr->type_id |= cpu_to_le32(TSI721_DMAD_IOF);
bd_ptr->bcount = cpu_to_le32(((desc->rio_addr & 0x3) << 30) |
- (sys_size << 26) | sg_dma_len(sg));
+ (sys_size << 26));
rio_addr = (desc->rio_addr >> 2) |
((u64)(desc->rio_addr_u & 0x3) << 62);
bd_ptr->raddr_lo = cpu_to_le32(rio_addr & 0xffffffff);
@@ -346,6 +328,20 @@ tsi721_fill_desc(struct tsi721_bdma_chan *bdma_chan,
return 0;
}
+static int
+tsi721_desc_fill_end(struct tsi721_tx_desc *desc)
+{
+ struct tsi721_dma_desc *bd_ptr = desc->hw_desc;
+
+ /* Update DMA descriptor */
+ if (desc->interrupt)
+ bd_ptr->type_id |= cpu_to_le32(TSI721_DMAD_IOF);
+ bd_ptr->bcount |= cpu_to_le32(desc->bcount & TSI721_DMAD_BCOUNT1);
+
+ return 0;
+}
+
+
static void tsi721_dma_chain_complete(struct tsi721_bdma_chan *bdma_chan,
struct tsi721_tx_desc *desc)
{
@@ -674,6 +670,7 @@ struct dma_async_tx_descriptor *tsi721_prep_rio_sg(struct dma_chan *dchan,
unsigned int i;
u32 sys_size = dma_to_mport(dchan->device)->sys_size;
enum dma_rtype rtype;
+ dma_addr_t next_addr = -1;
if (!sgl || !sg_len) {
dev_err(dchan->device->dev, "%s: No SG list\n", __func__);
@@ -704,36 +701,84 @@ struct dma_async_tx_descriptor *tsi721_prep_rio_sg(struct dma_chan *dchan,
for_each_sg(sgl, sg, sg_len, i) {
int err;
- dev_dbg(dchan->device->dev, "%s: sg #%d\n", __func__, i);
+ if (sg_dma_len(sg) > TSI721_BDMA_MAX_BCOUNT) {
+ dev_err(dchan->device->dev,
+ "%s: SG entry %d is too large\n", __func__, i);
+ goto err_desc_put;
+ }
+
+ /*
+ * If this sg entry forms contiguous block with previous one,
+ * try to merge it into existing DMA descriptor
+ */
+ if (desc) {
+ if (next_addr == sg_dma_address(sg) &&
+ desc->bcount + sg_dma_len(sg) <=
+ TSI721_BDMA_MAX_BCOUNT) {
+ /* Adjust byte count of the descriptor */
+ desc->bcount += sg_dma_len(sg);
+ goto entry_done;
+ }
+
+ /*
+ * Finalize this descriptor using total
+ * byte count value.
+ */
+ tsi721_desc_fill_end(desc);
+ dev_dbg(dchan->device->dev, "%s: desc final len: %d\n",
+ __func__, desc->bcount);
+ }
+
+ /*
+ * Obtain and initialize a new descriptor
+ */
desc = tsi721_desc_get(bdma_chan);
if (!desc) {
dev_err(dchan->device->dev,
- "Not enough descriptors available\n");
- goto err_desc_get;
+ "%s: Failed to get new descriptor for SG %d\n",
+ __func__, i);
+ goto err_desc_put;
}
- if (sg_is_last(sg))
- desc->interrupt = (flags & DMA_PREP_INTERRUPT) != 0;
- else
- desc->interrupt = false;
-
desc->destid = rext->destid;
desc->rio_addr = rio_addr;
desc->rio_addr_u = 0;
+ desc->bcount = sg_dma_len(sg);
+
+ dev_dbg(dchan->device->dev,
+ "sg%d desc: 0x%llx, addr: 0x%llx len: %d\n",
+ i, (u64)desc->txd.phys,
+ (unsigned long long)sg_dma_address(sg),
+ sg_dma_len(sg));
+
+ dev_dbg(dchan->device->dev,
+ "bd_ptr = %p did=%d raddr=0x%llx\n",
+ desc->hw_desc, desc->destid, desc->rio_addr);
- err = tsi721_fill_desc(bdma_chan, desc, sg, rtype, sys_size);
+ err = tsi721_desc_fill_init(desc, sg, rtype, sys_size);
if (err) {
dev_err(dchan->device->dev,
"Failed to build desc: %d\n", err);
- goto err_desc_get;
+ goto err_desc_put;
}
- rio_addr += sg_dma_len(sg);
+ next_addr = sg_dma_address(sg);
if (!first)
first = desc;
else
list_add_tail(&desc->desc_node, &first->tx_list);
+
+entry_done:
+ if (sg_is_last(sg)) {
+ desc->interrupt = (flags & DMA_PREP_INTERRUPT) != 0;
+ tsi721_desc_fill_end(desc);
+ dev_dbg(dchan->device->dev, "%s: desc final len: %d\n",
+ __func__, desc->bcount);
+ } else {
+ rio_addr += sg_dma_len(sg);
+ next_addr += sg_dma_len(sg);
+ }
}
first->txd.cookie = -EBUSY;
@@ -741,7 +786,7 @@ struct dma_async_tx_descriptor *tsi721_prep_rio_sg(struct dma_chan *dchan,
return &first->txd;
-err_desc_get:
+err_desc_put:
tsi721_desc_put(bdma_chan, first);
return NULL;
}
@@ -792,7 +837,7 @@ int tsi721_register_dma(struct tsi721_device *priv)
if (i == TSI721_DMACH_MAINT)
continue;
- bdma_chan->bd_num = 64;
+ bdma_chan->bd_num = TSI721_BDMA_BD_RING_SZ;
bdma_chan->regs = priv->regs + TSI721_DMAC_BASE(i);
bdma_chan->dchan.device = &mport->dma;