STRUCT PANTHOR_FW_CS_IFACE(9)

💅 NAME 💅

struct panthor_fw_cs_iface — the firmware command stream slot interface, bestie. It's from the Kernel API Manual and it's literally the little control panel for one command stream slot ✨

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🦋 SYNOPSIS 🦋

struct panthor_fw_cs_iface {
    spinlock_t lock;
    struct panthor_fw_cs_control_iface *control;
    struct panthor_fw_cs_input_iface *input;
    const struct panthor_fw_cs_output_iface *output;
 };

okay so it's four fields, that's the whole vibe, no cap 🎀

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🌸 Members 🌸

🔒 lock

The lock that protects access to the panthor_fw_cs_input_iface::req field. Yes queen, protect that field 👑

Why does it exist? Because we need to update the req field concurrently from the interrupt handler and from the scheduler logic. Two places, one field, so... lock. iykyk 💅

TODO: ideally we'd want to use a cmpxchg to update the req, but FW interface sections are mapped uncached/write-combined right now, and using cmpxchg on such mappings leads to SError faults. 💀 So nope. Revisit when we have 'SHARED' GPU mappings hooked up, bestie.

🎛️ control

The command stream slot control interface. It's how we expose command stream slot properties.

This interface is read-only — look, don't touch, periodt 🙈

📥 input

The command stream slot input interface. This one's for host updates/events — the host is the main character here ✨

📤 output

The command stream slot output interface. This is for FW (firmware) updates/events.

This interface is read-only too — output named but you only get to read it, the irony is not lost on us 😭

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🔥 SEE ALSO 🔥

• the kernel file ./drivers/gpu/drm/panthor/panthor_fw.h
• struct panthor_fw_csg_iface(9)
• struct panthor_fw_global_iface(9)
• panthor_fw_toggle_reqs(9)
• panthor_fw_update_reqs(9)

go read those too, they're all in the same friend group fr fr 🫶

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okay that's the whole page, you ate that 💖 this lil slice of kernel API lives at ./drivers/gpu/drm/panthor, dated October 2026, and it's filed under struct panthor_fw_cs_iface(9) — mwah, slay, bye 🎀🌈⭐