[PATCH] dmaengine: dw-edma: Add simple mode support

From: Devendra K Verma
Date: Wed Feb 19 2025 - 06:09:37 EST


Added the simple or non-linked list DMA mode of transfer.

Signed-off-by: Devendra K Verma <devverma@xxxxxxx>
---
drivers/dma/dw-edma/dw-edma-core.c | 38 +++++++++++++++++
drivers/dma/dw-edma/dw-edma-core.h | 1 +
drivers/dma/dw-edma/dw-hdma-v0-core.c | 59 ++++++++++++++++++++++++++-
3 files changed, 97 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c
index 68236247059d..bd975e6d419a 100644
--- a/drivers/dma/dw-edma/dw-edma-core.c
+++ b/drivers/dma/dw-edma/dw-edma-core.c
@@ -595,6 +595,43 @@ dw_edma_device_prep_interleaved_dma(struct dma_chan *dchan,
return dw_edma_device_transfer(&xfer);
}

+static struct dma_async_tx_descriptor *
+dw_edma_device_prep_dma_memcpy(struct dma_chan *dchan,
+ dma_addr_t dst,
+ dma_addr_t src, size_t len,
+ unsigned long flags)
+{
+ struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);
+ struct dw_edma_chunk *chunk;
+ struct dw_edma_burst *burst;
+ struct dw_edma_desc *desc;
+
+ desc = dw_edma_alloc_desc(chan);
+ if (unlikely(!desc))
+ return NULL;
+
+ chunk = dw_edma_alloc_chunk(desc);
+ if (unlikely(!chunk))
+ goto err_alloc;
+
+ burst = dw_edma_alloc_burst(chunk);
+ if (unlikely(!burst))
+ goto err_alloc;
+
+ burst->sar = src;
+ burst->dar = dst;
+ burst->sz = len;
+ chunk->non_ll_en = true;
+
+ desc->alloc_sz += burst->sz;
+
+ return vchan_tx_prep(&chan->vc, &desc->vd, flags);
+
+err_alloc:
+ dw_edma_free_desc(desc);
+ return NULL;
+}
+
static void dw_edma_done_interrupt(struct dw_edma_chan *chan)
{
struct dw_edma_desc *desc;
@@ -806,6 +843,7 @@ static int dw_edma_channel_setup(struct dw_edma *dw, u32 wr_alloc, u32 rd_alloc)
dma->device_prep_slave_sg = dw_edma_device_prep_slave_sg;
dma->device_prep_dma_cyclic = dw_edma_device_prep_dma_cyclic;
dma->device_prep_interleaved_dma = dw_edma_device_prep_interleaved_dma;
+ dma->device_prep_dma_memcpy = dw_edma_device_prep_dma_memcpy;

dma_set_max_seg_size(dma->dev, U32_MAX);

diff --git a/drivers/dma/dw-edma/dw-edma-core.h b/drivers/dma/dw-edma/dw-edma-core.h
index 71894b9e0b15..b496a1e5e326 100644
--- a/drivers/dma/dw-edma/dw-edma-core.h
+++ b/drivers/dma/dw-edma/dw-edma-core.h
@@ -58,6 +58,7 @@ struct dw_edma_chunk {

u8 cb;
struct dw_edma_region ll_region; /* Linked list */
+ bool non_ll_en;
};

struct dw_edma_desc {
diff --git a/drivers/dma/dw-edma/dw-hdma-v0-core.c b/drivers/dma/dw-edma/dw-hdma-v0-core.c
index e3f8db4fe909..0d5fdab925fd 100644
--- a/drivers/dma/dw-edma/dw-hdma-v0-core.c
+++ b/drivers/dma/dw-edma/dw-hdma-v0-core.c
@@ -225,7 +225,56 @@ static void dw_hdma_v0_sync_ll_data(struct dw_edma_chunk *chunk)
readl(chunk->ll_region.vaddr.io);
}

-static void dw_hdma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
+static void dw_hdma_v0_non_ll_start(struct dw_edma_chunk *chunk)
+{
+ struct dw_edma_chan *chan = chunk->chan;
+ struct dw_edma *dw = chan->dw;
+ struct dw_edma_burst *burst;
+ u64 addr;
+ u32 val;
+
+ burst = list_first_entry(&chunk->burst->list,
+ struct dw_edma_burst, list);
+ if (!burst)
+ return;
+
+ /* Source Address */
+ addr = burst->sar;
+
+ SET_CH_32(dw, chan->dir, chan->id, ch_en, BIT(0));
+
+ SET_CH_32(dw, chan->dir, chan->id, sar.lsb, lower_32_bits(addr));
+ SET_CH_32(dw, chan->dir, chan->id, sar.msb, upper_32_bits(addr));
+
+ /* Destination Address */
+ addr = burst->dar;
+
+ SET_CH_32(dw, chan->dir, chan->id, dar.lsb, lower_32_bits(addr));
+ SET_CH_32(dw, chan->dir, chan->id, dar.msb, upper_32_bits(addr));
+
+ /* Size */
+ SET_CH_32(dw, chan->dir, chan->id, transfer_size, burst->sz);
+
+ /* Interrupts */
+ val = GET_CH_32(dw, chan->dir, chan->id, int_setup) |
+ HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK |
+ HDMA_V0_LOCAL_STOP_INT_EN | HDMA_V0_LOCAL_ABORT_INT_EN;
+
+ if (!(dw->chip->flags & DW_EDMA_CHIP_LOCAL))
+ val |= HDMA_V0_REMOTE_STOP_INT_EN | HDMA_V0_REMOTE_ABORT_INT_EN;
+
+ SET_CH_32(dw, chan->dir, chan->id, int_setup, val);
+
+ /* Channel control */
+ val = GET_CH_32(dw, chan->dir, chan->id, control1);
+ val &= ~HDMA_V0_LINKLIST_EN;
+ SET_CH_32(dw, chan->dir, chan->id, control1, val);
+
+ /* Ring the doorbell */
+ SET_CH_32(dw, chan->dir, chan->id, doorbell, HDMA_V0_DOORBELL_START);
+}
+
+static void dw_hdma_v0_ll_start(struct dw_edma_chunk *chunk, bool first)
{
struct dw_edma_chan *chan = chunk->chan;
struct dw_edma *dw = chan->dw;
@@ -263,6 +312,14 @@ static void dw_hdma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
SET_CH_32(dw, chan->dir, chan->id, doorbell, HDMA_V0_DOORBELL_START);
}

+static void dw_hdma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
+{
+ if (!chunk->non_ll_en)
+ dw_hdma_v0_ll_start(chunk, first);
+ else
+ dw_hdma_v0_non_ll_start(chunk);
+}
+
static void dw_hdma_v0_core_ch_config(struct dw_edma_chan *chan)
{
struct dw_edma *dw = chan->dw;
--
2.43.0