[PATCH net-next 0/8] net: macb: Add XDP support and page pool integration

[Paolo Valerio <pvalerio@redhat.com>]

Tested on Raspberry Pi 5.
All the changes are intended for gem only.

The series consists of two main changes:

- Migration from netdev_alloc_skb() to page pool allocation model,
  enabling skb recycling.
  This also adds support for multi-descriptor frame reception,
  removing the previous single-descriptor approach and avoiding
  potentially large contiguous allocations for e.g. jumbo frames
  with CONFIG_PAGE_SIZE_4KB.

- XDP support: Initial XDP implementation supporting major
  verdicts (XDP_PASS, XDP_DROP, XDP_REDIRECT, XDP_TX) along with
  the ndo_xdp_xmit function for packet redirection.

The driver now advertises NETDEV_XDP_ACT_BASIC, NETDEV_XDP_ACT_REDIRECT,
NETDEV_XDP_ACT_NDO_XMIT capabilities.

Previous versions
=================
  - RFC v1: https://lore.kernel.org/netdev/20251119135330.551835-1-pvalerio@redhat.com/
  - RFC v2: https://lore.kernel.org/netdev/20251220235135.1078587-1-pvalerio@redhat.com/

RFC v2 -> v1
============
  - Removed bp->macbgem_ops.mog_init_rings(bp) call from macb_open()
  - Fixed includes (remove unneeded, moved one from header to macb_main.c)
  - Reverse xmas tree ordering (gem_rx, gem_rx_refill)
  - print_hex_dump_debug() instead of print_hex_dump()
  - Replaced rx frame length check with MACB_BIT(RX_EOF) for data_len
    calculation
  - Removed NET_IP_ALIGN handling in rx buffer size calculation
  - Updated debug format string to include rx_headroom and total size
  - Changed types to unsigned int in helper functions and variable
  - Removed unneeded line break

RFC v1 -> RFC v2
================
  - Squashed 1/6 and 2/6
  - Reworked rx_buffer_size computation. It no longer takes into
    accounts extra room.
  - A bunch of renaming (rx_offset => rx_headroom, removed MACB_MAX_PAD,
    MACB_PP_HEADROOM => XDP_PACKET_HEADROOM, data => ptr, xdp_q => xdp_rxq,
    macb_xdp() => gem_xdp(), macb_xdp_xmit() => gem_xdp_xmit())
  - Deduplicated buffer size computation in gem_xdp_valid_mtu()
    and gem_xdp_setup()
  - gem_xdp_setup() no longer close()/open()
  - Renaming from rx_skbuff to rx_buff is now got split in a separate commit
  - Open-coded gem_page_pool_get_buff()
  - Added missing rx_buff re-initialization in the error path during rx
  - Page pool creation failure now fails the device open
  - Moved xdp buff preparation inside gem_xdp_run()
  - Added missing rcu_access_pointer()
  - Turned return value in -EOPNOTSUPP for macb_xdp() on failure
  - moved tx_skb to tx_buff renaming to a separate commit
  - Removed some unneeded code and set MACB_TYPE_SKB for lp->rm9200_txq[desc].type as well
  - Replaced !!addr with a dedicated bool in macb_xdp_submit_frame()


Paolo Valerio (7):
  net: macb: rename rx_skbuff into rx_buff
  cadence: macb: Add page pool support handle multi-descriptor frame rx
  cadence: macb: use the current queue number for stats
  cadence: macb: add XDP support for gem
  cadence: macb: make macb_tx_skb generic
  cadence: macb: make tx path skb agnostic
  cadence: macb: introduce xmit support

Théo Lebrun (1):
  net: macb: move Rx buffers alloc from link up to open

 drivers/net/ethernet/cadence/Kconfig     |   1 +
 drivers/net/ethernet/cadence/macb.h      |  40 +-
 drivers/net/ethernet/cadence/macb_main.c | 827 +++++++++++++++++------
 3 files changed, 659 insertions(+), 209 deletions(-)

-- 
2.52.0