STRUCT MACHINE_DESC(9)

💖 struct machine_desc(9) 💖

Kernel API Manual bestie — okay so this is the page for struct machine_desc, and it's giving board-specific callback central. These are the board-specific callbacks, called from ARC common code. Each ARC board provides one using MACHINE_START()/MACHINE_END(), so a multi-platform kernel builds with an array of such descriptors. We extend the early DT scan to also match the DT's "compatible" string against the @dt_compat of all such descriptors, and the one with the highest "DT score" is selected as the global @machine_desc. periodt. 🌈

✨ NAME ✨

struct machine_desc — board-specific callbacks, called from ARC common code. Each ARC board provides one using MACHINE_START()/MACHINE_END(), so a multi-platform kernel builds with an array of such descriptors. We extend the early DT scan to also match the DT's "compatible" string against the @dt_compat of all such descriptors, and the one with the highest "DT score" is selected as the global @machine_desc. iykyk, that's the whole vibe. 🦋

🦋 SYNOPSIS 🦋

here's the whole struct, no cap:

       struct machine_desc {
           const char              *name;
           const char              **dt_compat;
           void (*init_early)(void);
           void (*init_per_cpu)(unsigned int);
           void (*init_machine)(void);
           void (*init_late)(void);
        };

🎀 Members 🎀

• name — Board/SoC name. literally the board or SoC's name, slay.
• dt_compat — Array of device tree 'compatible' strings.

⚠️ XXX: although only 1st entry is looked at.

• init_early — Very early callback [called from setup_arch]. early early, bestie.
• init_per_cpu — for each CPU as it is coming up (SMP as well as UP) [(M):init_IRQ, (o):start_kernel_secondary].
• init_machine — arch initcall level callback (e.g. populate static platform devices or parse Devicetree).
• init_late — Late initcall level callback. late but never forgotten.

🔥 SEE ALSO 🔥

• Kernel file ./arch/arc/include/asm/mach_desc.h — go read it, bestie.

mwah 💋 this one was served from ./arch/arc/include/asm, dated October 2026, and it's the struct machine_desc(9) page in the Kernel API Manual — periodt, stay slay, and may your DT score be the highest. 🫶✨