xilinx_mcdma_prep_slave_sg(9)

🎀 xilinx_mcdma_prep_slave_sg(9) 🎀

hiii bestie!! welcome to the Kernel API Manual 💖 this one's about xilinx_mcdma_prep_slave_sg, and no cap, it's lowkey the moment before anything actually moves. it's giving "packing the bags before the trip" energy 🧳✨

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🌸 NAME 🌸

xilinx_mcdma_prep_slave_sg — prepare descriptors for a DMA_SLAVE transaction 🦋

like, you're not doing the transfer yet, you're setting up the little descriptor guys that'll do it later. main character prep work fr fr 💅

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✨ SYNOPSIS ✨

struct dma_async_tx_descriptor * xilinx_mcdma_prep_slave_sg (struct
dma_chan *dchan , struct scatterlist *sgl , unsigned int sg_len , enum
dma_transfer_direction direction , unsigned long flags , void *context
);

look at that signature, iconic honestly 🔥 returns a struct dma_async_tx_descriptor *, so keep that in your notes 📝

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💜 ARGUMENTS 💜

okay so here's who's invited to the function call party 🎉

• dchan — the DMA channel 👑 this is your main character, the whole vibe
• sgl — the scatterlist to transfer to/from 🍓 it's the actual guest list of memory
• sg_len — number of entries in scatterlist 🔢 yes bestie, count them
• direction — DMA direction 🧭 which way the data's vibing
• flags — transfer ack flags 🚩 the little acknowledgment stickers
• context — APP words of the descriptor 🌈 extra lil words that ride along

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⭐ RETURN ⭐

Async transaction descriptor on success 💖 and NULL on failure 😭

so yeah, always check for that NULL, bestie. it's not being dramatic, it's being correct 🙈

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👑 SEE ALSO 👑

the whole friend group 🫶 starting with a Kernel file:

• 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_cdma_prep_memcpy(9)
• xilinx_dma_prep_peripheral_dma_vec(9)
• xilinx_dma_prep_slave_sg(9)
• xilinx_dma_prep_dma_cyclic(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)

like I said — the whole group chat 💀 every single one of them, don't leave anyone on read 💌

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and that's the page bestie!! 🧚 go prep those descriptors, you're gonna slay 🫶

later, legend 💜 — this one came from ./drivers/dma/xilinx, dated October 2026, and it's xilinx_mcdma_prep_slave_sg(9) all day ⭐