STRUCT MODE_REQ(9)

🌸 struct mode_req(9) — a.k.a. the Kernel API Manual's cutest little struct 🌸

okay so bestie, gather round, because this is a page from the Kernel API Manual and it's literally just a struct that tells you what an FPU mode needs to do to keep a program happy 💅 no cap, it's small, but it's important.

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✨ NAME ✨

struct mode_req — ABI FPU mode requirements 🫶

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🎀 SYNOPSIS 🎀

struct mode_req {
    bool single;
    bool soft;
    bool fr1;
    bool frdefault;
    bool fre;
 };

that's it, that's the whole vibe. five lil bools and a dream ✨

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💖 Members 💖

• single — the program being loaded needs an FPU, but it's only gonna issue single precision instructions, which means it can run in either FR0 or FR1. lowkey flexible 🌈
• soft — the soft(-float) requirement, meaning the program being loaded has no FPU dependency at all (i.e. it has no FPU instructions). it's giving "unbothered, moisturized, in its lane" 🧚
• fr1 — the program being loaded depends on the FPU being in FR=1 mode. periodt.
• frdefault — the program being loaded depends on the default FPU mode. that is, FR0 for O32 and FR1 for N32/N64. iykyk 🔥
• fre — the program being loaded depends on FPU with FRE=1. this mode is a bridge which uses FR=1 whilst still being able to maintain full compatibility with pre-existing code using the O32 FP32 ABI. she's a connector, she's a diplomat, she's iconic 👑

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🦋 Description 🦋

so like, if you want more info about the FP ABIs, it's literally right here bestie:

https://dmz-portal.mips.com/wiki/MIPS_O32_ABI_-_FR0_and_FR1_Interlinking#10.4.1._Basic_mode_set-up

go read it, it's giving lore 🍓

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⭐ SEE ALSO ⭐

• Kernel file ./arch/mips/kernel/elf.c — go peek, she's right there 🙈

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💀 reminder for the girlies: these are requirement flags, not suggestions. the loader is checking the vibe and it will absolutely notice if you're lying.

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okay that's the whole page, mwah 💜 this little gem lives in ./arch/mips/kernel, dated October 2026, and no I will not stop talking about it. slay, bye bestie! 🎀✨