[PATCH for-next 4/4] dmaengine: ti: k3-udma: Use the TR counter helper for slave_sg and cyclic

Peter Ujfalusi
2020-01-27T13:20:45Z

Use the generic TR setup function to get the TR counters for both cyclic
and slave_sg transfers.
This way the period_size for cyclic and sg_dma_len() for slave_sg can be
as large as (SZ_64K - 1) * (SZ_64K - 1) and we can handle cases when the
length is >SZ_64K and a prime number.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
drivers/dma/ti/k3-udma.c | 130 ++++++++++++++++++++++++++-------------
1 file changed, 88 insertions(+), 42 deletions(-)

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 9b00013d6f63..1dba47c662c4 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -2079,31 +2079,31 @@ udma_prep_slave_sg_tr(struct udma_chan *uc, struct scatterlist *sgl,
unsigned int sglen, enum dma_transfer_direction dir,
unsigned long tx_flags, void *context)
{
- enum dma_slave_buswidth dev_width;
struct scatterlist *sgent;
struct udma_desc *d;
- size_t tr_size;
struct cppi5_tr_type1_t *tr_req = NULL;
+ u16 tr0_cnt0, tr0_cnt1, tr1_cnt0;
unsigned int i;
- u32 burst;
+ size_t tr_size;
+ int num_tr = 0;
+ int tr_idx = 0;

- if (dir == DMA_DEV_TO_MEM) {
- dev_width = uc->cfg.src_addr_width;
- burst = uc->cfg.src_maxburst;
- } else if (dir == DMA_MEM_TO_DEV) {
- dev_width = uc->cfg.dst_addr_width;
- burst = uc->cfg.dst_maxburst;
- } else {
- dev_err(uc->ud->dev, "%s: bad direction?\n", __func__);
+ if (!is_slave_direction(dir)) {
+ dev_err(uc->ud->dev, "Only slave cyclic is supported\n");
return NULL;
}

- if (!burst)
- burst = 1;
+ /* estimate the number of TRs we will need */
+ for_each_sg(sgl, sgent, sglen, i) {
+ if (sg_dma_len(sgent) < SZ_64K)
+ num_tr++;
+ else
+ num_tr += 2;
+ }

/* Now allocate and setup the descriptor. */
tr_size = sizeof(struct cppi5_tr_type1_t);
- d = udma_alloc_tr_desc(uc, tr_size, sglen, dir);
+ d = udma_alloc_tr_desc(uc, tr_size, num_tr, dir);
if (!d)
return NULL;

@@ -2111,19 +2111,46 @@ udma_prep_slave_sg_tr(struct udma_chan *uc, struct scatterlist *sgl,

tr_req = d->hwdesc[0].tr_req_base;
for_each_sg(sgl, sgent, sglen, i) {
- d->residue += sg_dma_len(sgent);
+ dma_addr_t sg_addr = sg_dma_address(sgent);
+
+ num_tr = udma_get_tr_counters(sg_dma_len(sgent), __ffs(sg_addr),
+ &tr0_cnt0, &tr0_cnt1, &tr1_cnt0);
+ if (num_tr < 0) {
+ dev_err(uc->ud->dev, "size %u is not supported\n",
+ sg_dma_len(sgent));
+ udma_free_hwdesc(uc, d);
+ kfree(d);
+ return NULL;
+ }

cppi5_tr_init(&tr_req[i].flags, CPPI5_TR_TYPE1, false, false,
CPPI5_TR_EVENT_SIZE_COMPLETION, 0);
cppi5_tr_csf_set(&tr_req[i].flags, CPPI5_TR_CSF_SUPR_EVT);

- tr_req[i].addr = sg_dma_address(sgent);
- tr_req[i].icnt0 = burst * dev_width;
- tr_req[i].dim1 = burst * dev_width;
- tr_req[i].icnt1 = sg_dma_len(sgent) / tr_req[i].icnt0;
+ tr_req[tr_idx].addr = sg_addr;
+ tr_req[tr_idx].icnt0 = tr0_cnt0;
+ tr_req[tr_idx].icnt1 = tr0_cnt1;
+ tr_req[tr_idx].dim1 = tr0_cnt0;
+ tr_idx++;
+
+ if (num_tr == 2) {
+ cppi5_tr_init(&tr_req[tr_idx].flags, CPPI5_TR_TYPE1,
+ false, false,
+ CPPI5_TR_EVENT_SIZE_COMPLETION, 0);
+ cppi5_tr_csf_set(&tr_req[tr_idx].flags,
+ CPPI5_TR_CSF_SUPR_EVT);
+
+ tr_req[tr_idx].addr = sg_addr + tr0_cnt1 * tr0_cnt0;
+ tr_req[tr_idx].icnt0 = tr1_cnt0;
+ tr_req[tr_idx].icnt1 = 1;
+ tr_req[tr_idx].dim1 = tr1_cnt0;
+ tr_idx++;
+ }
+
+ d->residue += sg_dma_len(sgent);
}

- cppi5_tr_csf_set(&tr_req[i - 1].flags, CPPI5_TR_CSF_EOP);
+ cppi5_tr_csf_set(&tr_req[tr_idx - 1].flags, CPPI5_TR_CSF_EOP);

return d;
}
@@ -2428,47 +2455,66 @@ udma_prep_dma_cyclic_tr(struct udma_chan *uc, dma_addr_t buf_addr,
size_t buf_len, size_t period_len,
enum dma_transfer_direction dir, unsigned long flags)
{
- enum dma_slave_buswidth dev_width;
struct udma_desc *d;
- size_t tr_size;
+ size_t tr_size, period_addr;
struct cppi5_tr_type1_t *tr_req;
- unsigned int i;
unsigned int periods = buf_len / period_len;
- u32 burst;
+ u16 tr0_cnt0, tr0_cnt1, tr1_cnt0;
+ unsigned int i;
+ int num_tr;

- if (dir == DMA_DEV_TO_MEM) {
- dev_width = uc->cfg.src_addr_width;
- burst = uc->cfg.src_maxburst;
- } else if (dir == DMA_MEM_TO_DEV) {
- dev_width = uc->cfg.dst_addr_width;
- burst = uc->cfg.dst_maxburst;
- } else {
- dev_err(uc->ud->dev, "%s: bad direction?\n", __func__);
+ if (!is_slave_direction(dir)) {
+ dev_err(uc->ud->dev, "Only slave cyclic is supported\n");
return NULL;
}

- if (!burst)
- burst = 1;
+ num_tr = udma_get_tr_counters(period_len, __ffs(buf_addr), &tr0_cnt0,
+ &tr0_cnt1, &tr1_cnt0);
+ if (num_tr < 0) {
+ dev_err(uc->ud->dev, "size %zu is not supported\n",
+ period_len);
+ return NULL;
+ }

/* Now allocate and setup the descriptor. */
tr_size = sizeof(struct cppi5_tr_type1_t);
- d = udma_alloc_tr_desc(uc, tr_size, periods, dir);
+ d = udma_alloc_tr_desc(uc, tr_size, periods * num_tr, dir);
if (!d)
return NULL;

tr_req = d->hwdesc[0].tr_req_base;
+ period_addr = buf_addr;
for (i = 0; i < periods; i++) {
- cppi5_tr_init(&tr_req[i].flags, CPPI5_TR_TYPE1, false, false,
- CPPI5_TR_EVENT_SIZE_COMPLETION, 0);
+ int tr_idx = i * num_tr;

- tr_req[i].addr = buf_addr + period_len * i;
- tr_req[i].icnt0 = dev_width;
- tr_req[i].icnt1 = period_len / dev_width;
- tr_req[i].dim1 = dev_width;
+ cppi5_tr_init(&tr_req[tr_idx].flags, CPPI5_TR_TYPE1, false,
+ false, CPPI5_TR_EVENT_SIZE_COMPLETION, 0);
+
+ tr_req[tr_idx].addr = period_addr;
+ tr_req[tr_idx].icnt0 = tr0_cnt0;
+ tr_req[tr_idx].icnt1 = tr0_cnt1;
+ tr_req[tr_idx].dim1 = tr0_cnt0;
+
+ if (num_tr == 2) {
+ cppi5_tr_csf_set(&tr_req[tr_idx].flags,
+ CPPI5_TR_CSF_SUPR_EVT);
+ tr_idx++;
+
+ cppi5_tr_init(&tr_req[tr_idx].flags, CPPI5_TR_TYPE1,
+ false, false,
+ CPPI5_TR_EVENT_SIZE_COMPLETION, 0);
+
+ tr_req[tr_idx].addr = period_addr + tr0_cnt1 * tr0_cnt0;
+ tr_req[tr_idx].icnt0 = tr1_cnt0;
+ tr_req[tr_idx].icnt1 = 1;
+ tr_req[tr_idx].dim1 = tr1_cnt0;
+ }

if (!(flags & DMA_PREP_INTERRUPT))
- cppi5_tr_csf_set(&tr_req[i].flags,
+ cppi5_tr_csf_set(&tr_req[tr_idx].flags,
CPPI5_TR_CSF_SUPR_EVT);
+
+ period_addr += period_len;
}

return d;
--
Peter