STRUCT VDEC_AP_IPI_DEC_START(9)

🌸 struct vdec_ap_ipi_dec_start(9) 🌸

okay so bestie, this is a page from the Kernel API Manual and it's literally all about one lil struct, and honestly? she's kind of a big deal. 💅

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✨ NAME ✨

struct vdec_ap_ipi_dec_start — the struct that exists for AP_IPIMSG_DEC_START. that's it. that's her whole job. iconic behavior honestly 🎀

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🦋 SYNOPSIS 🦋

struct vdec_ap_ipi_dec_start {
    uint32_t msg_id;
    union {
      uint32_t vpu_inst_addr;
      uint32_t inst_id;
    };
    uint32_t data[3];
    u32 codec_type;
 };

like, look at her. struct goals fr fr ✨

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💖 Members 💖

• msg_id — this one's set to AP_IPIMSG_DEC_START. no notes, that's just what she is 🫶
• {unnamed_union} — it's anonymous. she has no name. mysterious. main character energy lowkey 🌈
• vpu_inst_addr — the VPU decoder instance address. ⚠️ only used if the ABI version is < 2, so mind your versions bestie
• inst_id — the instance ID. this one's the other half of the union — used if the ABI version is >= 2 🔥
• data — header info, and it changes depending on the codec, so pay attention:
  • H264 decoder: [0]:buf_sz [1]:nal_start
  • VP8 decoder: [0]:width/height
  • VP9 decoder: [0]:profile, [1][2] width/height

yeah she's doing a lot of work in three little slots, we love a multitasker 💜

• codec_type — the codec fourcc. short, sweet, slay 🍓

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🧚 SEE ALSO 🧚

• Kernel file ./drivers/media/platform/mediatek/vcodec/decoder/vdec_ipi_msg.h
• struct vdec_ap_ipi_cmd(9)
• struct vdec_vpu_ipi_ack(9)
• struct vdec_ap_ipi_init(9)
• struct vdec_vpu_ipi_init_ack(9)
• struct vdec_ap_ipi_get_param(9)
• struct vdec_vpu_ipi_get_param_ack(9)

like the whole friend group, go read them too 💖✨

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ngl this page came from the kernel source around ./drivers/media/platform/media... and it's dated October 2026 — so yeah, future-dated lore 👑. go off bestie, you now fully understand struct vdec_ap_ipi_dec_start. periodt. 💅🎀