#define EDMA_CHANS 64
#endif /* CONFIG_ARCH_DAVINCI_DA8XX */
-/* Max of 16 segments per channel to conserve PaRAM slots */
-#define MAX_NR_SG 16
+/*
+ * Max of 20 segments per channel to conserve PaRAM slots
+ * Also note that MAX_NR_SG should be atleast the no.of periods
+ * that are required for ASoC, otherwise DMA prep calls will
+ * fail. Today davinci-pcm is the only user of this driver and
+ * requires atleast 17 slots, so we setup the default to 20.
+ */
+#define MAX_NR_SG 20
#define EDMA_MAX_SLOTS MAX_NR_SG
#define EDMA_DESCRIPTORS 16
struct edma_desc {
struct virt_dma_desc vdesc;
struct list_head node;
+ int cyclic;
int absync;
int pset_nr;
int processed;
* then setup a link to the dummy slot, this results in all future
* events being absorbed and that's OK because we're done
*/
- if (edesc->processed == edesc->pset_nr)
- edma_link(echan->slot[nslots-1], echan->ecc->dummy_slot);
+ if (edesc->processed == edesc->pset_nr) {
+ if (edesc->cyclic)
+ edma_link(echan->slot[nslots-1], echan->slot[1]);
+ else
+ edma_link(echan->slot[nslots-1],
+ echan->ecc->dummy_slot);
+ }
edma_resume(echan->ch_num);
return ret;
}
+/*
+ * A PaRAM set configuration abstraction used by other modes
+ * @chan: Channel who's PaRAM set we're configuring
+ * @pset: PaRAM set to initialize and setup.
+ * @src_addr: Source address of the DMA
+ * @dst_addr: Destination address of the DMA
+ * @burst: In units of dev_width, how much to send
+ * @dev_width: How much is the dev_width
+ * @dma_length: Total length of the DMA transfer
+ * @direction: Direction of the transfer
+ */
+static int edma_config_pset(struct dma_chan *chan, struct edmacc_param *pset,
+ dma_addr_t src_addr, dma_addr_t dst_addr, u32 burst,
+ enum dma_slave_buswidth dev_width, unsigned int dma_length,
+ enum dma_transfer_direction direction)
+{
+ struct edma_chan *echan = to_edma_chan(chan);
+ struct device *dev = chan->device->dev;
+ int acnt, bcnt, ccnt, cidx;
+ int src_bidx, dst_bidx, src_cidx, dst_cidx;
+ int absync;
+
+ acnt = dev_width;
+ /*
+ * If the maxburst is equal to the fifo width, use
+ * A-synced transfers. This allows for large contiguous
+ * buffer transfers using only one PaRAM set.
+ */
+ if (burst == 1) {
+ /*
+ * For the A-sync case, bcnt and ccnt are the remainder
+ * and quotient respectively of the division of:
+ * (dma_length / acnt) by (SZ_64K -1). This is so
+ * that in case bcnt over flows, we have ccnt to use.
+ * Note: In A-sync tranfer only, bcntrld is used, but it
+ * only applies for sg_dma_len(sg) >= SZ_64K.
+ * In this case, the best way adopted is- bccnt for the
+ * first frame will be the remainder below. Then for
+ * every successive frame, bcnt will be SZ_64K-1. This
+ * is assured as bcntrld = 0xffff in end of function.
+ */
+ absync = false;
+ ccnt = dma_length / acnt / (SZ_64K - 1);
+ bcnt = dma_length / acnt - ccnt * (SZ_64K - 1);
+ /*
+ * If bcnt is non-zero, we have a remainder and hence an
+ * extra frame to transfer, so increment ccnt.
+ */
+ if (bcnt)
+ ccnt++;
+ else
+ bcnt = SZ_64K - 1;
+ cidx = acnt;
+ } else {
+ /*
+ * If maxburst is greater than the fifo address_width,
+ * use AB-synced transfers where A count is the fifo
+ * address_width and B count is the maxburst. In this
+ * case, we are limited to transfers of C count frames
+ * of (address_width * maxburst) where C count is limited
+ * to SZ_64K-1. This places an upper bound on the length
+ * of an SG segment that can be handled.
+ */
+ absync = true;
+ bcnt = burst;
+ ccnt = dma_length / (acnt * bcnt);
+ if (ccnt > (SZ_64K - 1)) {
+ dev_err(dev, "Exceeded max SG segment size\n");
+ return -EINVAL;
+ }
+ cidx = acnt * bcnt;
+ }
+
+ if (direction == DMA_MEM_TO_DEV) {
+ src_bidx = acnt;
+ src_cidx = cidx;
+ dst_bidx = 0;
+ dst_cidx = 0;
+ } else if (direction == DMA_DEV_TO_MEM) {
+ src_bidx = 0;
+ src_cidx = 0;
+ dst_bidx = acnt;
+ dst_cidx = cidx;
+ } else {
+ dev_err(dev, "%s: direction not implemented yet\n", __func__);
+ return -EINVAL;
+ }
+
+ pset->opt = EDMA_TCC(EDMA_CHAN_SLOT(echan->ch_num));
+ /* Configure A or AB synchronized transfers */
+ if (absync)
+ pset->opt |= SYNCDIM;
+
+ pset->src = src_addr;
+ pset->dst = dst_addr;
+
+ pset->src_dst_bidx = (dst_bidx << 16) | src_bidx;
+ pset->src_dst_cidx = (dst_cidx << 16) | src_cidx;
+
+ pset->a_b_cnt = bcnt << 16 | acnt;
+ pset->ccnt = ccnt;
+ /*
+ * Only time when (bcntrld) auto reload is required is for
+ * A-sync case, and in this case, a requirement of reload value
+ * of SZ_64K-1 only is assured. 'link' is initially set to NULL
+ * and then later will be populated by edma_execute.
+ */
+ pset->link_bcntrld = 0xffffffff;
+ return absync;
+}
+
static struct dma_async_tx_descriptor *edma_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl,
unsigned int sg_len, enum dma_transfer_direction direction,
struct edma_chan *echan = to_edma_chan(chan);
struct device *dev = chan->device->dev;
struct edma_desc *edesc;
- dma_addr_t dev_addr;
+ dma_addr_t src_addr = 0, dst_addr = 0;
enum dma_slave_buswidth dev_width;
u32 burst;
struct scatterlist *sg;
- int acnt, bcnt, ccnt, src, dst, cidx;
- int src_bidx, dst_bidx, src_cidx, dst_cidx;
- int i, nslots;
+ int i, nslots, ret;
if (unlikely(!echan || !sgl || !sg_len))
return NULL;
if (direction == DMA_DEV_TO_MEM) {
- dev_addr = echan->cfg.src_addr;
+ src_addr = echan->cfg.src_addr;
dev_width = echan->cfg.src_addr_width;
burst = echan->cfg.src_maxburst;
} else if (direction == DMA_MEM_TO_DEV) {
- dev_addr = echan->cfg.dst_addr;
+ dst_addr = echan->cfg.dst_addr;
dev_width = echan->cfg.dst_addr_width;
burst = echan->cfg.dst_maxburst;
} else {
if (echan->slot[i] < 0) {
kfree(edesc);
dev_err(dev, "Failed to allocate slot\n");
- kfree(edesc);
return NULL;
}
}
/* Configure PaRAM sets for each SG */
for_each_sg(sgl, sg, sg_len, i) {
-
- acnt = dev_width;
-
- /*
- * If the maxburst is equal to the fifo width, use
- * A-synced transfers. This allows for large contiguous
- * buffer transfers using only one PaRAM set.
- */
- if (burst == 1) {
- edesc->absync = false;
- ccnt = sg_dma_len(sg) / acnt / (SZ_64K - 1);
- bcnt = sg_dma_len(sg) / acnt - ccnt * (SZ_64K - 1);
- if (bcnt)
- ccnt++;
- else
- bcnt = SZ_64K - 1;
- cidx = acnt;
- /*
- * If maxburst is greater than the fifo address_width,
- * use AB-synced transfers where A count is the fifo
- * address_width and B count is the maxburst. In this
- * case, we are limited to transfers of C count frames
- * of (address_width * maxburst) where C count is limited
- * to SZ_64K-1. This places an upper bound on the length
- * of an SG segment that can be handled.
- */
- } else {
- edesc->absync = true;
- bcnt = burst;
- ccnt = sg_dma_len(sg) / (acnt * bcnt);
- if (ccnt > (SZ_64K - 1)) {
- dev_err(dev, "Exceeded max SG segment size\n");
- kfree(edesc);
- return NULL;
- }
- cidx = acnt * bcnt;
+ /* Get address for each SG */
+ if (direction == DMA_DEV_TO_MEM)
+ dst_addr = sg_dma_address(sg);
+ else
+ src_addr = sg_dma_address(sg);
+
+ ret = edma_config_pset(chan, &edesc->pset[i], src_addr,
+ dst_addr, burst, dev_width,
+ sg_dma_len(sg), direction);
+ if (ret < 0) {
+ kfree(edesc);
+ return NULL;
}
- if (direction == DMA_MEM_TO_DEV) {
- src = sg_dma_address(sg);
- dst = dev_addr;
- src_bidx = acnt;
- src_cidx = cidx;
- dst_bidx = 0;
- dst_cidx = 0;
- } else {
- src = dev_addr;
- dst = sg_dma_address(sg);
- src_bidx = 0;
- src_cidx = 0;
- dst_bidx = acnt;
- dst_cidx = cidx;
- }
-
- edesc->pset[i].opt = EDMA_TCC(EDMA_CHAN_SLOT(echan->ch_num));
- /* Configure A or AB synchronized transfers */
- if (edesc->absync)
- edesc->pset[i].opt |= SYNCDIM;
+ edesc->absync = ret;
/* If this is the last in a current SG set of transactions,
enable interrupts so that next set is processed */
/* If this is the last set, enable completion interrupt flag */
if (i == sg_len - 1)
edesc->pset[i].opt |= TCINTEN;
+ }
- edesc->pset[i].src = src;
- edesc->pset[i].dst = dst;
+ return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags);
+}
- edesc->pset[i].src_dst_bidx = (dst_bidx << 16) | src_bidx;
- edesc->pset[i].src_dst_cidx = (dst_cidx << 16) | src_cidx;
+static struct dma_async_tx_descriptor *edma_prep_dma_cyclic(
+ struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
+ size_t period_len, enum dma_transfer_direction direction,
+ unsigned long tx_flags, void *context)
+{
+ struct edma_chan *echan = to_edma_chan(chan);
+ struct device *dev = chan->device->dev;
+ struct edma_desc *edesc;
+ dma_addr_t src_addr, dst_addr;
+ enum dma_slave_buswidth dev_width;
+ u32 burst;
+ int i, ret, nslots;
+
+ if (unlikely(!echan || !buf_len || !period_len))
+ return NULL;
+
+ if (direction == DMA_DEV_TO_MEM) {
+ src_addr = echan->cfg.src_addr;
+ dst_addr = buf_addr;
+ dev_width = echan->cfg.src_addr_width;
+ burst = echan->cfg.src_maxburst;
+ } else if (direction == DMA_MEM_TO_DEV) {
+ src_addr = buf_addr;
+ dst_addr = echan->cfg.dst_addr;
+ dev_width = echan->cfg.dst_addr_width;
+ burst = echan->cfg.dst_maxburst;
+ } else {
+ dev_err(dev, "%s: bad direction?\n", __func__);
+ return NULL;
+ }
+
+ if (dev_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) {
+ dev_err(dev, "Undefined slave buswidth\n");
+ return NULL;
+ }
+
+ if (unlikely(buf_len % period_len)) {
+ dev_err(dev, "Period should be multiple of Buffer length\n");
+ return NULL;
+ }
+
+ nslots = (buf_len / period_len) + 1;
+
+ /*
+ * Cyclic DMA users such as audio cannot tolerate delays introduced
+ * by cases where the number of periods is more than the maximum
+ * number of SGs the EDMA driver can handle at a time. For DMA types
+ * such as Slave SGs, such delays are tolerable and synchronized,
+ * but the synchronization is difficult to achieve with Cyclic and
+ * cannot be guaranteed, so we error out early.
+ */
+ if (nslots > MAX_NR_SG)
+ return NULL;
+
+ edesc = kzalloc(sizeof(*edesc) + nslots *
+ sizeof(edesc->pset[0]), GFP_ATOMIC);
+ if (!edesc) {
+ dev_dbg(dev, "Failed to allocate a descriptor\n");
+ return NULL;
+ }
+
+ edesc->cyclic = 1;
+ edesc->pset_nr = nslots;
+
+ dev_dbg(dev, "%s: nslots=%d\n", __func__, nslots);
+ dev_dbg(dev, "%s: period_len=%d\n", __func__, period_len);
+ dev_dbg(dev, "%s: buf_len=%d\n", __func__, buf_len);
+
+ for (i = 0; i < nslots; i++) {
+ /* Allocate a PaRAM slot, if needed */
+ if (echan->slot[i] < 0) {
+ echan->slot[i] =
+ edma_alloc_slot(EDMA_CTLR(echan->ch_num),
+ EDMA_SLOT_ANY);
+ if (echan->slot[i] < 0) {
+ dev_err(dev, "Failed to allocate slot\n");
+ return NULL;
+ }
+ }
+
+ if (i == nslots - 1) {
+ memcpy(&edesc->pset[i], &edesc->pset[0],
+ sizeof(edesc->pset[0]));
+ break;
+ }
+
+ ret = edma_config_pset(chan, &edesc->pset[i], src_addr,
+ dst_addr, burst, dev_width, period_len,
+ direction);
+ if (ret < 0)
+ return NULL;
- edesc->pset[i].a_b_cnt = bcnt << 16 | acnt;
- edesc->pset[i].ccnt = ccnt;
- edesc->pset[i].link_bcntrld = 0xffffffff;
+ if (direction == DMA_DEV_TO_MEM)
+ dst_addr += period_len;
+ else
+ src_addr += period_len;
+ dev_dbg(dev, "%s: Configure period %d of buf:\n", __func__, i);
+ dev_dbg(dev,
+ "\n pset[%d]:\n"
+ " chnum\t%d\n"
+ " slot\t%d\n"
+ " opt\t%08x\n"
+ " src\t%08x\n"
+ " dst\t%08x\n"
+ " abcnt\t%08x\n"
+ " ccnt\t%08x\n"
+ " bidx\t%08x\n"
+ " cidx\t%08x\n"
+ " lkrld\t%08x\n",
+ i, echan->ch_num, echan->slot[i],
+ edesc->pset[i].opt,
+ edesc->pset[i].src,
+ edesc->pset[i].dst,
+ edesc->pset[i].a_b_cnt,
+ edesc->pset[i].ccnt,
+ edesc->pset[i].src_dst_bidx,
+ edesc->pset[i].src_dst_cidx,
+ edesc->pset[i].link_bcntrld);
+
+ edesc->absync = ret;
+
+ /*
+ * Enable interrupts for every period because callback
+ * has to be called for every period.
+ */
+ edesc->pset[i].opt |= TCINTEN;
}
return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags);
unsigned long flags;
struct edmacc_param p;
- /* Pause the channel */
- edma_pause(echan->ch_num);
+ edesc = echan->edesc;
+
+ /* Pause the channel for non-cyclic */
+ if (!edesc || (edesc && !edesc->cyclic))
+ edma_pause(echan->ch_num);
switch (ch_status) {
- case DMA_COMPLETE:
+ case EDMA_DMA_COMPLETE:
spin_lock_irqsave(&echan->vchan.lock, flags);
- edesc = echan->edesc;
if (edesc) {
- if (edesc->processed == edesc->pset_nr) {
+ if (edesc->cyclic) {
+ vchan_cyclic_callback(&edesc->vdesc);
+ } else if (edesc->processed == edesc->pset_nr) {
dev_dbg(dev, "Transfer complete, stopping channel %d\n", ch_num);
edma_stop(echan->ch_num);
vchan_cookie_complete(&edesc->vdesc);
+ edma_execute(echan);
} else {
dev_dbg(dev, "Intermediate transfer complete on channel %d\n", ch_num);
+ edma_execute(echan);
}
-
- edma_execute(echan);
}
spin_unlock_irqrestore(&echan->vchan.lock, flags);
break;
- case DMA_CC_ERROR:
+ case EDMA_DMA_CC_ERROR:
spin_lock_irqsave(&echan->vchan.lock, flags);
edma_read_slot(EDMA_CHAN_SLOT(echan->slot[0]), &p);
unsigned long flags;
ret = dma_cookie_status(chan, cookie, txstate);
- if (ret == DMA_SUCCESS || !txstate)
+ if (ret == DMA_COMPLETE || !txstate)
return ret;
spin_lock_irqsave(&echan->vchan.lock, flags);
struct device *dev)
{
dma->device_prep_slave_sg = edma_prep_slave_sg;
+ dma->device_prep_dma_cyclic = edma_prep_dma_cyclic;
dma->device_alloc_chan_resources = edma_alloc_chan_resources;
dma->device_free_chan_resources = edma_free_chan_resources;
dma->device_issue_pending = edma_issue_pending;
projects / linux-drm-fsl-dcu.git / blobdiff