SETUP_PC_GUCRC(9)

👑 SETUP_PC_GUCRC

okay so this is a section 9 kernel API page, bestie — it's literally the ABI cheat-sheet for the SETUP_PC_GUCRC H2G action, and it's giving "tiny page, all the tea." We're talking bit layouts here, so grab a snack 🍓 because precision is the whole vibe.

🎀 the first dword, bits 31:0

This is what the message looks like when you lay it out field by field 💅

• bit 0 — ORIGIN = GUC_HXG_ORIGIN_HOST_ ✨
• bits 30:28 — TYPE = GUC_HXG_TYPE_FAST_REQUEST_ 🔥
• bits 27:16 — DATA0 = MBZ — yes bestie, the must-be-zero slot, leave it alone 🫶
• bits 15:0 — ACTION = GUC_ACTION_HOST2GUC_SETUP_PC_GUCRC = 0x3004 👑

Not me stressing that 0x3004 is the exact action value — no cap, copy it character for character. 😭

🌈 dword 1, bits 31:0 — the MODE moment

• word 1, bits 31:0 — MODE = GUCRC_HOST_CONTROL(0), GUCRC_FIRMWARE_CONTROL(1) 🦋

so like, MODE takes one of those two values and that's the entire second dword, periodt. Two options, zero drama 🧚

✨ SEE ALSO ✨

• Kernel file ./drivers/gpu/drm/xe/abi/guc_actions_slpc_abi.h 📁
• SLPC SHARED DATA STRUCTURE(9)
• SLPC H2G MESSAGE FORMAT(9)

go read those if you want the full lore, iykyk 💜

and that's the page!! 🫶 it came out of ./drivers/gpu/drm/xe/abi, dated October 2026, and honestly? iconic. slay, go build your messages correctly bestie 💖🎀