[PATCH 1/3] dmaengine: Add support for 2D DMA operation

Aatif Mushtaq
2025-02-10T06:43:12Z

Add a new dma engine API to support 2D DMA operations.
The API will be used to get the descriptor for 2D transfer based on
the 16-bit immediate to define the stride length between consecuitive
source address or destination address after every DMA load and
store instruction is processed.

Signed-off-by: Aatif Mushtaq <aatif4.m@samsung.com>
---
include/linux/dmaengine.h | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index b137fdb56093..8a73b2147983 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -833,6 +833,7 @@ struct dma_filter {
* be called after period_len bytes have been transferred.
* @device_prep_interleaved_dma: Transfer expression in a generic way.
* @device_prep_dma_imm_data: DMA's 8 byte immediate data to the dst address
+ * @device_prep_2d_dma_memcpy: prepares a 2D memcpy operation
* @device_caps: May be used to override the generic DMA slave capabilities
* with per-channel specific ones
* @device_config: Pushes a new configuration to a channel, return 0 or an error
@@ -938,6 +939,9 @@ struct dma_device {
struct dma_async_tx_descriptor *(*device_prep_dma_imm_data)(
struct dma_chan *chan, dma_addr_t dst, u64 data,
unsigned long flags);
+ struct dma_async_tx_descriptor *(*device_prep_2d_dma_memcpy)(
+ struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
+ size_t len, u16 src_imm, u16 dest_imm, unsigned long flags);

void (*device_caps)(struct dma_chan *chan, struct dma_slave_caps *caps);
int (*device_config)(struct dma_chan *chan, struct dma_slave_config *config);
@@ -1087,6 +1091,27 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memcpy(
len, flags);
}

+/**
+ * device_prep_2d_dma_memcpy() - Prepare a DMA 2D memcpy descriptor.
+ * @chan: The channel to be used for this descriptor
+ * @dest: Address of the destination data for a DMA channel
+ * @src: Address of the source data for a DMA channel
+ * @len: The total size of data
+ * @src_imm: The immediate value to be added to the src address register
+ * @dest_imm: The immediate value to be added to the dst address register
+ * @flags: DMA engine flags
+ */
+static inline struct dma_async_tx_descriptor *device_prep_2d_dma_memcpy(
+ struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
+ size_t len, u16 src_imm, u16 dest_imm, unsigned long flags)
+{
+ if (!chan || !chan->device || !chan->device->device_prep_2d_dma_memcpy)
+ return NULL;
+
+ return chan->device->device_prep_2d_dma_memcpy(chan, dest, src, len,
+ src_imm, dest_imm, flags);
+}
+
static inline bool dmaengine_is_metadata_mode_supported(struct dma_chan *chan,
enum dma_desc_metadata_mode mode)
{
--
2.17.1