xilinx_cdma_prep_memcpy(9)

💅 xilinx_cdma_prep_memcpy(9) — the Kernel API Manual, bestie edition 🎀

okay so real talk, this one is from the Kernel API Manual (yes, the actual manpage name, we're official now 💖) and it's genuinely one of the more chill functions in the Xilinx DMA cinematic universe. it does exactly one thing and it does it slayfully: it builds the descriptors for a memcpy transaction. no cap, that's the whole gig ✨

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🌸 NAME 🌸

xilinx_cdma_prep_memcpy — prepare descriptors for a memcpy transaction

like, it's the prep girlie. it gets the descriptor vibes ready so the actual copying can happen later 👑

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✨ SYNOPSIS ✨

struct dma_async_tx_descriptor * xilinx_cdma_prep_memcpy (struct
dma_chan *dchan , dma_addr_t dma_dst , dma_addr_t dma_src , size_t len ,
unsigned long flags );

it's giving "returns a struct dma_async_tx_descriptor *" energy, and it takes five lil arguments. we'll get into each one, don't worry 🫶

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🦋 ARGUMENTS 🦋

okay bestie, let's meet the cast:

• dchan — the DMA channel. main character energy, this is the channel we're operating on 💅
• dma_dst — destination address. where the bytes are going, i.e. the address they're moving to 🎯
• dma_src — source address. where the bytes are coming from, i.e. their origin story 🌱
• len — transfer length. how much we're actually moving, the "size of the vibe" if you will 📏
• flags — transfer ack flags. the acknowledgement flags, kept exactly as they are, no notes 🚩

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🔥 RETURN 🔥

• Async transaction descriptor on success — iconic, we ate 💖
• NULL on failure — which is the sad path, and honestly? we don't talk about her 😭

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👑 SEE ALSO 👑

the whole Xilinx DMA extended universe, fr fr. like we are not alone here:

• Kernel file ./drivers/dma/xilinx/xilinx_dma.c
• struct xilinx_vdma_desc_hw(9)
• struct xilinx_axidma_desc_hw(9)
• struct xilinx_aximcdma_desc_hw(9)
• struct xilinx_cdma_desc_hw(9)
• struct xilinx_vdma_tx_segment(9)
• struct xilinx_axidma_tx_segment(9)
• struct xilinx_aximcdma_tx_segment(9)
• struct xilinx_cdma_tx_segment(9)
• struct xilinx_dma_tx_descriptor(9)
• struct xilinx_dma_chan(9)
• enum xdma_ip_type(9)
• struct xilinx_dma_device(9)
• vdma_desc_write_64(9)
• xilinx_dma_get_metadata_ptr(9)
• xilinx_vdma_alloc_tx_segment(9)
• xilinx_cdma_alloc_tx_segment(9)
• xilinx_axidma_alloc_tx_segment(9)
• xilinx_aximcdma_alloc_tx_segment(9)
• xilinx_dma_free_tx_segment(9)
• xilinx_mcdma_free_tx_segment(9)
• xilinx_cdma_free_tx_segment(9)
• xilinx_vdma_free_tx_segment(9)
• xilinx_dma_alloc_tx_descriptor(9)
• xilinx_dma_free_tx_descriptor(9)
• xilinx_dma_free_desc_list(9)
• xilinx_dma_free_descriptors(9)
• xilinx_dma_free_chan_resources(9)
• xilinx_dma_get_residue(9)
• xilinx_dma_chan_handle_cyclic(9)
• xilinx_dma_chan_desc_cleanup(9)
• xilinx_dma_do_tasklet(9)
• xilinx_dma_alloc_chan_resources(9)
• xilinx_dma_calc_copysize(9)
• xilinx_dma_tx_status(9)
• xilinx_dma_stop_transfer(9)
• xilinx_cdma_stop_transfer(9)
• xilinx_dma_start(9)
• xilinx_vdma_start_transfer(9)
• xilinx_cdma_start_transfer(9)
• xilinx_dma_start_transfer(9)
• xilinx_mcdma_start_transfer(9)
• xilinx_dma_issue_pending(9)
• xilinx_dma_device_config(9)
• xilinx_dma_complete_descriptor(9)
• xilinx_dma_reset(9)
• xilinx_dma_chan_reset(9)
• xilinx_mcdma_irq_handler(9)
• xilinx_dma_irq_handler(9)
• append_desc_queue(9)
• xilinx_dma_tx_submit(9)
• xilinx_vdma_dma_prep_interleaved(9)
• xilinx_dma_prep_peripheral_dma_vec(9)
• xilinx_dma_prep_slave_sg(9)
• xilinx_dma_prep_dma_cyclic(9)
• xilinx_mcdma_prep_slave_sg(9)
• xilinx_dma_terminate_all(9)
• xilinx_vdma_channel_set_config(9)
• xilinx_dma_chan_remove(9)
• xilinx_dma_chan_probe(9)
• xilinx_dma_child_probe(9)
• of_dma_xilinx_xlate(9)
• xilinx_dma_probe(9)
• xilinx_dma_remove(9)

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lowkey a whole friend group 💀 every single one of them is in this manpage too, so like… go read them, iykyk 🧚

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and that's the page bestie 🌈 that was xilinx_cdma_prep_memcpy(9), coming to you from ./drivers/dma/xilinx, dated October 2026, in the Kernel API Manual — mwah, go prep some memcpy descriptors, ily, bye 💜🎀