fsl_rio_rx_handler(9)

💖 fsl_rio_rx_handler(9) 💖

okay so bestie, we're in the Kernel API Manual today and the star of the show is fsl_rio_rx_handler — literally the MPC85xx inbound message interrupt handler. yes it's a mouthful, no we're not scared of it 💅

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✨ SYNOPSIS ✨

irqreturn_t fsl_rio_rx_handler (int irq , void *dev_instance );

like, that's the whole vibe check right there 🫶

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🎀 ARGUMENTS 🎀

• irq — the Linux interrupt number, your classic little "which interrupt is this" int 🦋
• dev_instance — a pointer to interrupt-specific data, aka the lil payload that comes along for the ride ✨

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🌸 DESCRIPTION 🌸

okay so here's what she does: she handles inbound message interrupts. that's the main character job 👑

and then, the way that she does it — she executes a registered inbound mailbox event handler, and then she acks the interrupt occurrence. that's it, that's the whole bit. execute the handler, ack the interrupt, no cap 🔥

it's giving "small function, big responsibilities" fr fr 💀

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💜 SEE ALSO 💜

• the kernel file ./arch/powerpc/sysdev/fsl_rmu.c — that's her home, that's where she lives 🏠
• fsl_rio_tx_handler(9)
• fsl_rio_dbell_handler(9)
• fsl_rio_port_write_handler(9)
• fsl_rio_pw_enable(9)
• fsl_rio_port_write_init(9)
• fsl_rio_doorbell_send(9)
• fsl_add_outb_message(9)
• fsl_open_outb_mbox(9)
• fsl_close_outb_mbox(9)
• fsl_open_inb_mbox(9)
• fsl_close_inb_mbox(9)
• fsl_add_inb_buffer(9)
• fsl_get_inb_message(9)
• fsl_rio_doorbell_init(9)

like, the whole friend group 🫶 go read all of them, iykyk ⭐

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ngl bestie, if you're poking at RapidIO mailbox stuff on MPC85xx, this is your girl. read the whole squad above before you start ✨

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and that's a wrap, babe 🎀 this page lives in ./arch/powerpc/sysdev and the version/date situation is October 2026 — mwah, go ack some interrupts, ily 💜🌈