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-rw-r--r--drivers/dma/at_xdmac.c42
-rw-r--r--drivers/dma/fsldma.c2
-rw-r--r--drivers/dma/iop-adma.c8
-rw-r--r--drivers/dma/mv_xor.c4
-rw-r--r--drivers/dma/pxa_dma.c8
-rw-r--r--drivers/dma/qcom_bam_dma.c14
6 files changed, 61 insertions, 17 deletions
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index 64f5d1bdbb48..8e304b1befc5 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -176,6 +176,7 @@
#define AT_XDMAC_MAX_CHAN 0x20
#define AT_XDMAC_MAX_CSIZE 16 /* 16 data */
#define AT_XDMAC_MAX_DWIDTH 8 /* 64 bits */
+#define AT_XDMAC_RESIDUE_MAX_RETRIES 5
#define AT_XDMAC_DMA_BUSWIDTHS\
(BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
@@ -1395,8 +1396,8 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
struct at_xdmac_desc *desc, *_desc;
struct list_head *descs_list;
enum dma_status ret;
- int residue;
- u32 cur_nda, mask, value;
+ int residue, retry;
+ u32 cur_nda, check_nda, cur_ubc, mask, value;
u8 dwidth = 0;
unsigned long flags;
@@ -1433,7 +1434,42 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
cpu_relax();
}
+ /*
+ * When processing the residue, we need to read two registers but we
+ * can't do it in an atomic way. AT_XDMAC_CNDA is used to find where
+ * we stand in the descriptor list and AT_XDMAC_CUBC is used
+ * to know how many data are remaining for the current descriptor.
+ * Since the dma channel is not paused to not loose data, between the
+ * AT_XDMAC_CNDA and AT_XDMAC_CUBC read, we may have change of
+ * descriptor.
+ * For that reason, after reading AT_XDMAC_CUBC, we check if we are
+ * still using the same descriptor by reading a second time
+ * AT_XDMAC_CNDA. If AT_XDMAC_CNDA has changed, it means we have to
+ * read again AT_XDMAC_CUBC.
+ * Memory barriers are used to ensure the read order of the registers.
+ * A max number of retries is set because unlikely it can never ends if
+ * we are transferring a lot of data with small buffers.
+ */
cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
+ rmb();
+ cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
+ for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
+ rmb();
+ check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
+
+ if (likely(cur_nda == check_nda))
+ break;
+
+ cur_nda = check_nda;
+ rmb();
+ cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
+ }
+
+ if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
+ ret = DMA_ERROR;
+ goto spin_unlock;
+ }
+
/*
* Remove size of all microblocks already transferred and the current
* one. Then add the remaining size to transfer of the current
@@ -1446,7 +1482,7 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda)
break;
}
- residue += at_xdmac_chan_read(atchan, AT_XDMAC_CUBC) << dwidth;
+ residue += cur_ubc << dwidth;
dma_set_residue(txstate, residue);
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index 2209f75fdf05..aac85c30c2cf 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -522,6 +522,8 @@ static dma_cookie_t fsldma_run_tx_complete_actions(struct fsldma_chan *chan,
chan_dbg(chan, "LD %p callback\n", desc);
txd->callback(txd->callback_param);
}
+
+ dma_descriptor_unmap(txd);
}
/* Run any dependencies */
diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c
index e4f43125e0fb..f039cfadf17b 100644
--- a/drivers/dma/iop-adma.c
+++ b/drivers/dma/iop-adma.c
@@ -1300,10 +1300,10 @@ static int iop_adma_probe(struct platform_device *pdev)
* note: writecombine gives slightly better performance, but
* requires that we explicitly flush the writes
*/
- adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev,
- plat_data->pool_size,
- &adev->dma_desc_pool,
- GFP_KERNEL);
+ adev->dma_desc_pool_virt = dma_alloc_wc(&pdev->dev,
+ plat_data->pool_size,
+ &adev->dma_desc_pool,
+ GFP_KERNEL);
if (!adev->dma_desc_pool_virt) {
ret = -ENOMEM;
goto err_free_adev;
diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index 14091f878f80..3922a5d56806 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -964,8 +964,8 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
* requires that we explicitly flush the writes
*/
mv_chan->dma_desc_pool_virt =
- dma_alloc_writecombine(&pdev->dev, MV_XOR_POOL_SIZE,
- &mv_chan->dma_desc_pool, GFP_KERNEL);
+ dma_alloc_wc(&pdev->dev, MV_XOR_POOL_SIZE, &mv_chan->dma_desc_pool,
+ GFP_KERNEL);
if (!mv_chan->dma_desc_pool_virt)
return ERR_PTR(-ENOMEM);
diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c
index f2a0310ae771..debca824bed6 100644
--- a/drivers/dma/pxa_dma.c
+++ b/drivers/dma/pxa_dma.c
@@ -583,6 +583,8 @@ static void set_updater_desc(struct pxad_desc_sw *sw_desc,
(PXA_DCMD_LENGTH & sizeof(u32));
if (flags & DMA_PREP_INTERRUPT)
updater->dcmd |= PXA_DCMD_ENDIRQEN;
+ if (sw_desc->cyclic)
+ sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
}
static bool is_desc_completed(struct virt_dma_desc *vd)
@@ -673,6 +675,10 @@ static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
dev_dbg(&chan->vc.chan.dev->device,
"%s(): checking txd %p[%x]: completed=%d\n",
__func__, vd, vd->tx.cookie, is_desc_completed(vd));
+ if (to_pxad_sw_desc(vd)->cyclic) {
+ vchan_cyclic_callback(vd);
+ break;
+ }
if (is_desc_completed(vd)) {
list_del(&vd->node);
vchan_cookie_complete(vd);
@@ -1080,7 +1086,7 @@ pxad_prep_dma_cyclic(struct dma_chan *dchan,
return NULL;
pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
- dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH | period_len);
+ dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH & period_len);
dev_dbg(&chan->vc.chan.dev->device,
"%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
__func__, (unsigned long)buf_addr, len, period_len, dir, flags);
diff --git a/drivers/dma/qcom_bam_dma.c b/drivers/dma/qcom_bam_dma.c
index 5a250cdc8376..d34aef7a101b 100644
--- a/drivers/dma/qcom_bam_dma.c
+++ b/drivers/dma/qcom_bam_dma.c
@@ -502,8 +502,8 @@ static int bam_alloc_chan(struct dma_chan *chan)
return 0;
/* allocate FIFO descriptor space, but only if necessary */
- bchan->fifo_virt = dma_alloc_writecombine(bdev->dev, BAM_DESC_FIFO_SIZE,
- &bchan->fifo_phys, GFP_KERNEL);
+ bchan->fifo_virt = dma_alloc_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
+ &bchan->fifo_phys, GFP_KERNEL);
if (!bchan->fifo_virt) {
dev_err(bdev->dev, "Failed to allocate desc fifo\n");
@@ -538,8 +538,8 @@ static void bam_free_chan(struct dma_chan *chan)
bam_reset_channel(bchan);
spin_unlock_irqrestore(&bchan->vc.lock, flags);
- dma_free_writecombine(bdev->dev, BAM_DESC_FIFO_SIZE, bchan->fifo_virt,
- bchan->fifo_phys);
+ dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE, bchan->fifo_virt,
+ bchan->fifo_phys);
bchan->fifo_virt = NULL;
/* mask irq for pipe/channel */
@@ -1231,9 +1231,9 @@ static int bam_dma_remove(struct platform_device *pdev)
bam_dma_terminate_all(&bdev->channels[i].vc.chan);
tasklet_kill(&bdev->channels[i].vc.task);
- dma_free_writecombine(bdev->dev, BAM_DESC_FIFO_SIZE,
- bdev->channels[i].fifo_virt,
- bdev->channels[i].fifo_phys);
+ dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
+ bdev->channels[i].fifo_virt,
+ bdev->channels[i].fifo_phys);
}
tasklet_kill(&bdev->task);
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