dcn32_enough...es_for_subvp(9)

💅 dcn32_enough_pipes_for_subvp — Kernel API Manual ✨

okay so bestie, welcome to the kernel API manual for dcn32_enough_pipes_for_subvp(9) — yes that's the whole name, yes it's a mouthful, no we're not shortening it, it's iconic as is 🎀

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🌸 NAME 🌸

dcn32_enough_pipes_for_subvp — the function whose entire job is checking if there are, quote unquote, "enough" pipes for SubVP. That's it. That's the gig. Lowkey simple, highkey important 💖

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✨ SYNOPSIS ✨

bool dcn32_enough_pipes_for_subvp (struct dc *dc , struct dc_state
*context );

she returns a bool, she takes two pointers, she minds her own business 🦋

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🫶 ARGUMENTS 🫶

• dc — the current dc state. what we've got going on right now, no cap.
• context — the new dc state. the future we're all manifesting ✨

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👑 DESCRIPTION 👑

so the vibe check here is: this function returns true if there are enough free pipes to create the required phantom pipes for any given stream — and to be clear, that's any stream that does not already have a phantom pipe assigned. not me being picky, that's literally the spec 💅

e.g. picture a 2 stream config where the first stream uses one pipe and the second stream uses 2 pipes (i.e. pipe split) — in that case this function will return true, because there is 1 remaining pipe which can be used as the phantom pipe for the non pipe split pipe. literally math, bestie, and she ate 🔥

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⭐ RETURN ⭐

true if there are enough free pipes to assign phantom pipes to at least one stream that does not already have phantom pipes assigned. otherwise false 💀 (no phantom pipe for you, sorry babe)

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🌈 SEE ALSO 🌈

the whole friend group, fr fr — first up the kernel file ./drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c, then:

• dcn32_helper_populate_phantom_dlg_params(9)
• dcn32_set_phantom_stream_timing(9)
• dcn32_get_num_free_pipes(9)
• dcn32_assign_subvp_pipe(9)
• subvp_subvp_schedulable(9)
• subvp_drr_schedulable(9)
• subvp_vblank_schedulable(9)
• subvp_subvp_admissable(9)
• subvp_validate_static_schedulability(9)
• dcn32_allow_subvp_high_refresh_rate(9)
• dcn32_determine_max_vratio_prefetch(9)
• dcn32_assign_fpo_vactive_candidate(9)
• dcn32_find_vactive_pipe(9)

like I said — the whole squad 🧚💜

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ngl if you're here at 3am debugging pipe allocation, you're doing amazing, drink some water 🍓

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and that's a wrap bestie!! this page lives at ./drivers/gpu/drm/amd/display/... and it's dated October 2026, manual name dcn32_enough...es_for_subvp(9) — short and sweet, just like her 😭💖 periodt ✨