pdc_tx_list_sg_add(9)

🌸 pdc_tx_list_sg_add(9) 🌸

okay so bestie, this is the Kernel API Manual entry for pdc_tx_list_sg_add, and it's literally about adding scatterlist buffers into the transmit descriptors for a given SPU. Those scatterlist buffers are the ones carrying the data for a SPU request message. slay. 💅

✨ NAME ✨

pdc_tx_list_sg_add — add the buffers in a scatterlist to the transmit descriptors for a given SPU. The scatterlist buffers contain the data for a SPU request message. 🦋

🎀 SYNOPSIS 🎀

int pdc_tx_list_sg_add (struct pdc_state *pdcs , struct scatterlist *sg
       );

💖 ARGUMENTS 💖

• pdcs — PDC state for the SPU that will process this request.
• sg — Scatterlist whose buffers contain part of the SPU request.

🌈 DESCRIPTION 🌈

okay so here's the vibe: if a scatterlist buffer is larger than PDC_DMA_BUF_MAX, the function writes multiple descriptors for that buffer, and every one of those descriptors is <= PDC_DMA_BUF_MAX byte in length. no cap, it really said "one descriptor per buffer? not always, bestie." ✨

👑 RETURN 👑

It gives you PDC_SUCCESS if successful, and < 0 otherwise. periodt. 💅

🦋 SEE ALSO 🦋

Kernel file: ./drivers/mailbox/bcm-pdc-mailbox.c

• pdc_setup_debugfs(9)
• pdc_build_rxd(9)
• pdc_build_txd(9)
• pdc_receive_one(9)
• pdc_receive(9)
• pdc_tx_list_final(9)
• pdc_rx_list_init(9)
• pdc_rx_list_sg_add(9)
• pdc_irq_handler(9)
• pdc_work_cb(9)
• pdc_ring_init(9)
• pdc_desc_count(9)
• pdc_rings_full(9)
• pdc_last_tx_done(9)
• pdc_send_data(9)
• pdc_hw_init(9)
• pdc_hw_disable(9)
• pdc_rx_buf_pool_create(9)
• pdc_interrupts_init(9)
• pdc_mb_init(9)
• pdc_dt_read(9)
• pdc_probe(9)

okay byeee bestie — signing off from ./drivers/mailbox, dated October 2026 💖✨