sdma_init(9)

💅 sdma_init(9) — Kernel API Manual

okay so bestie, welcome to sdma_init(9), straight out of the Kernel API Manual ✨ this is the little function that gets called when a device gets probed, and trust me, it's doing more than it looks like 👑

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🌸 NAME

sdma_init — called when device probed 🫶

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⭐ SYNOPSIS

int sdma_init (struct hfi1_devdata *dd , u8 port );

like, that's the whole signature, no cap 💅

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🎀 ARGUMENTS

• dd — an hfi1_devdata, iykyk 🦋
• port — the port number, and rn it's currently only zero (yes, really, just zero, that's the whole vibe 🙈)

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✨ DESCRIPTION

So what does it actually do? It initializes each sde and its csrs 💖 that's it, that's the job, and it slays at it.

Also key detail: interrupts are not required to be enabled for this to work — so you don't have to have your interrupt situation figured out first, it's giving low-maintenance icon behavior 🌈

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🔥 RETURN

• 0 — success, we ate 👑
• -errno — failure, and it hands you back the negative errno so you know what went wrong 😭

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🦋 SEE ALSO

the kernel file lives at ./drivers/infiniband/hw/hfi1/sdma.c 📁 and honestly the whole sdma friend group shows up here:

• sdma_state_name(9)
• sdma_get_descq_cnt(9)
• sdma_engine_get_vl(9)
• sdma_select_engine_vl(9)
• sdma_select_engine_sc(9)
• sdma_seqfile_dump_cpu_list(9)
• sdma_map_init(9)
• sdma_clean(9)
• sdma_all_running(9)
• sdma_start(9)
• sdma_exit(9)
• __sdma_txclean(9)
• sdma_engine_error(9)
• sdma_seqfile_dump_sde(9)
• sdma_send_txreq(9)
• sdma_send_txlist(9)
• sdma_ahg_alloc(9)
• sdma_ahg_free(9)
• _sdma_engine_progress_schedule(9)

like, the whole squad fr fr 💜

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ngl if you're reading this at 3am while debugging a probe path, you're doing amazing, drink some water 🍓

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and that's the tea bestie 🧚 this lil page came from ./drivers/infiniband/hw/hfi1, dated October 2026 — mwah, periodt 💅💖