[PATCH v3 3/5] dmaengine: sun6i: Add cyclic capability
Jean-Francois Moine
moinejf at free.fr
Fri Mar 18 07:18:32 PDT 2016
DMA cyclic transfers are required by audio streaming.
Signed-off-by: Jean-Francois Moine <moinejf at free.fr>
---
drivers/dma/sun6i-dma.c | 129 +++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 122 insertions(+), 7 deletions(-)
diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c
index 9378fda..3f73123 100644
--- a/drivers/dma/sun6i-dma.c
+++ b/drivers/dma/sun6i-dma.c
@@ -147,6 +147,8 @@ struct sun6i_vchan {
struct dma_slave_config cfg;
struct sun6i_pchan *phy;
u8 port;
+ u8 irq_type;
+ bool cyclic;
};
struct sun6i_dma_dev {
@@ -257,6 +259,30 @@ static inline s8 convert_buswidth(enum dma_slave_buswidth addr_width)
return addr_width >> 1;
}
+static size_t sun6i_get_chan_size(struct sun6i_pchan *pchan)
+{
+ struct sun6i_desc *txd = pchan->desc;
+ struct sun6i_dma_lli *lli;
+ size_t bytes;
+ dma_addr_t pos;
+
+ pos = readl(pchan->base + DMA_CHAN_LLI_ADDR);
+ bytes = readl(pchan->base + DMA_CHAN_CUR_CNT);
+
+ if (pos == LLI_LAST_ITEM)
+ return bytes;
+
+ for (lli = txd->v_lli; lli; lli = lli->v_lli_next) {
+ if (lli->p_lli_next == pos) {
+ for (lli = lli->v_lli_next; lli; lli = lli->v_lli_next)
+ bytes += lli->len;
+ break;
+ }
+ }
+
+ return bytes;
+}
+
static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev,
struct sun6i_dma_lli *next,
dma_addr_t next_phy,
@@ -345,8 +371,12 @@ static int sun6i_dma_start_desc(struct sun6i_vchan *vchan)
irq_reg = pchan->idx / DMA_IRQ_CHAN_NR;
irq_offset = pchan->idx % DMA_IRQ_CHAN_NR;
+ vchan->irq_type = vchan->cyclic ? DMA_IRQ_PKG : DMA_IRQ_QUEUE;
+
irq_val = readl(sdev->base + DMA_IRQ_EN(irq_reg));
- irq_val |= DMA_IRQ_QUEUE << (irq_offset * DMA_IRQ_CHAN_WIDTH);
+ irq_val &= ~((DMA_IRQ_HALF | DMA_IRQ_PKG | DMA_IRQ_QUEUE) <<
+ (irq_offset * DMA_IRQ_CHAN_WIDTH));
+ irq_val |= vchan->irq_type << (irq_offset * DMA_IRQ_CHAN_WIDTH);
writel(irq_val, sdev->base + DMA_IRQ_EN(irq_reg));
writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR);
@@ -443,11 +473,12 @@ static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id)
writel(status, sdev->base + DMA_IRQ_STAT(i));
for (j = 0; (j < DMA_IRQ_CHAN_NR) && status; j++) {
- if (status & DMA_IRQ_QUEUE) {
- pchan = sdev->pchans + j;
- vchan = pchan->vchan;
-
- if (vchan) {
+ pchan = sdev->pchans + j;
+ vchan = pchan->vchan;
+ if (vchan && (status & vchan->irq_type)) {
+ if (vchan->cyclic) {
+ vchan_cyclic_callback(&pchan->desc->vd);
+ } else {
spin_lock(&vchan->vc.lock);
vchan_cookie_complete(&pchan->desc->vd);
pchan->done = pchan->desc;
@@ -656,6 +687,78 @@ err_lli_free:
return NULL;
}
+static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic(
+ struct dma_chan *chan,
+ dma_addr_t buf_addr,
+ size_t buf_len,
+ size_t period_len,
+ enum dma_transfer_direction dir,
+ unsigned long flags)
+{
+ struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
+ struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
+ struct dma_slave_config *sconfig = &vchan->cfg;
+ struct sun6i_dma_lli *v_lli, *prev = NULL;
+ struct sun6i_desc *txd;
+ dma_addr_t p_lli;
+ u32 lli_cfg;
+ unsigned int i, periods = buf_len / period_len;
+ int ret;
+
+ ret = set_config(sdev, sconfig, dir, &lli_cfg);
+ if (ret) {
+ dev_err(chan2dev(chan), "Invalid DMA configuration\n");
+ return NULL;
+ }
+
+ txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
+ if (!txd)
+ return NULL;
+
+ for (i = 0; i < periods; i++){
+ v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
+ if (!v_lli) {
+ dev_err(sdev->slave.dev, "Failed to alloc lli memory\n");
+ goto err_lli_free;
+ }
+
+ v_lli->len = period_len;
+ v_lli->para = NORMAL_WAIT;
+
+ if (dir == DMA_MEM_TO_DEV) {
+ v_lli->src = buf_addr + period_len * i;
+ v_lli->dst = sconfig->dst_addr;
+ v_lli->cfg = lli_cfg |
+ DMA_CHAN_CFG_DST_IO_MODE |
+ DMA_CHAN_CFG_SRC_LINEAR_MODE |
+ DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
+ DMA_CHAN_CFG_DST_DRQ(vchan->port);
+ } else {
+ v_lli->src = sconfig->src_addr;
+ v_lli->dst = buf_addr + period_len * i;
+ v_lli->cfg = lli_cfg |
+ DMA_CHAN_CFG_DST_LINEAR_MODE |
+ DMA_CHAN_CFG_SRC_IO_MODE |
+ DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
+ DMA_CHAN_CFG_SRC_DRQ(vchan->port);
+ }
+
+ prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd);
+ }
+
+ prev->p_lli_next = txd->p_lli; /* cyclic list */
+
+ vchan->cyclic = true;
+
+ return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
+
+err_lli_free:
+ for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
+ dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
+ kfree(txd);
+ return NULL;
+}
+
static int sun6i_dma_config(struct dma_chan *chan,
struct dma_slave_config *config)
{
@@ -725,6 +828,16 @@ static int sun6i_dma_terminate_all(struct dma_chan *chan)
spin_lock_irqsave(&vchan->vc.lock, flags);
+ if (vchan->cyclic) {
+ vchan->cyclic = false;
+ if (pchan && pchan->desc) {
+ struct virt_dma_desc *vd = &pchan->desc->vd;
+ struct virt_dma_chan *vc = &vchan->vc;
+
+ list_add_tail(&vd->node, &vc->desc_completed);
+ }
+ }
+
vchan_get_all_descriptors(&vchan->vc, &head);
if (pchan) {
@@ -772,7 +885,7 @@ static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan,
} else if (!pchan || !pchan->desc) {
bytes = 0;
} else {
- bytes = readl(pchan->base + DMA_CHAN_CUR_CNT);
+ bytes = sun6i_get_chan_size(pchan);
}
spin_unlock_irqrestore(&vchan->vc.lock, flags);
@@ -978,6 +1091,7 @@ static int sun6i_dma_probe(struct platform_device *pdev)
dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask);
dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask);
dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask);
+ dma_cap_set(DMA_CYCLIC, sdc->slave.cap_mask);
INIT_LIST_HEAD(&sdc->slave.channels);
sdc->slave.device_free_chan_resources = sun6i_dma_free_chan_resources;
@@ -985,6 +1099,7 @@ static int sun6i_dma_probe(struct platform_device *pdev)
sdc->slave.device_issue_pending = sun6i_dma_issue_pending;
sdc->slave.device_prep_slave_sg = sun6i_dma_prep_slave_sg;
sdc->slave.device_prep_dma_memcpy = sun6i_dma_prep_dma_memcpy;
+ sdc->slave.device_prep_dma_cyclic = sun6i_dma_prep_dma_cyclic;
sdc->slave.copy_align = DMAENGINE_ALIGN_4_BYTES;
sdc->slave.device_config = sun6i_dma_config;
sdc->slave.device_pause = sun6i_dma_pause;
--
2.7.4
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