net: stmmac: Add Tx HWTS support to XDP ZC

This patch enables transmit hardware timestamp support to XDP zero copy
via XDP Tx metadata framework.

This patchset is tested with tools/testing/selftests/bpf/xdp_hw_metadata
on Intel Tiger Lake platform. Below are the test steps and results.

Command on DUT:
sudo ./xdp_hw_metadata <interface name>
sudo hwstamp_ctl -i <interface name> -t 1 -r 1

Command on Link Partner:
echo -n xdp | nc -u -q1 <destination IPv4 addr> 9091

Result:
xsk_ring_cons__peek: 1
0x55bbbf08b6d0: rx_desc[2]->addr=8c100 addr=8c100 comp_addr=8c100 EoP
No rx_hash err=-95
rx_timestamp:  1677762688429141540 (sec:1677762688.4291)
HW RX-time:   1677762688429141540 (sec:1677762688.4291) delta to User RX-time sec:0.0003 (250.665 usec)
XDP RX-time:   1677762688429375597 (sec:1677762688.4294) delta to User RX-time sec:0.0000 (16.608 usec)
0x55bbbf08b6d0: ping-pong with csum=561c (want f488) csum_start=34 csum_offset=6
0x55bbbf08b6d0: complete tx idx=2 addr=2008
tx_timestamp:  1677762688431127273 (sec:1677762688.4311)
HW TX-complete-time:   1677762688431127273 (sec:1677762688.4311) delta to User TX-complete-time sec:0.0083 (8331.655 usec)
XDP RX-time:   1677762688429375597 (sec:1677762688.4294) delta to User TX-complete-time sec:0.0101 (10083.331 usec)
HW RX-time:   1677762688429141540 (sec:1677762688.4291) delta to HW TX-complete-time sec:0.0020 (1985.733 usec)
0x55bbbf08b6d0: complete rx idx=130 addr=8c100

Signed-off-by: Song Yoong Siang <yoong.siang.song@intel.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20231127190319.1190813-6-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index cd7a9768de5f..686c94c2e8a7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -51,6 +51,7 @@ struct stmmac_tx_info {
 	bool last_segment;
 	bool is_jumbo;
 	enum stmmac_txbuf_type buf_type;
+	struct xsk_tx_metadata_compl xsk_meta;
 };
 
 #define STMMAC_TBS_AVAIL	BIT(0)
@@ -100,6 +101,17 @@ struct stmmac_xdp_buff {
 	struct dma_desc *ndesc;
 };
 
+struct stmmac_metadata_request {
+	struct stmmac_priv *priv;
+	struct dma_desc *tx_desc;
+	bool *set_ic;
+};
+
+struct stmmac_xsk_tx_complete {
+	struct stmmac_priv *priv;
+	struct dma_desc *desc;
+};
+
 struct stmmac_rx_queue {
 	u32 rx_count_frames;
 	u32 queue_index;