net/sfc/base: add description of the PS packets layout

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>

diff --git a/drivers/net/sfc/base/ef10_rx.c b/drivers/net/sfc/base/ef10_rx.c
index 53ea054..69ebc2d 100644 (file)
--- a/drivers/net/sfc/base/ef10_rx.c
+++ b/drivers/net/sfc/base/ef10_rx.c
@@ -804,6 +804,16 @@ ef10_rx_qpush_ps_credits(
        rxq_state->eers_rx_packed_stream_credits = 0;
 }
 
+/*
+ * In accordance with SF-112241-TC the received data has the following layout:
+ *  - 8 byte pseudo-header which consist of:
+ *    - 4 byte little-endian timestamp
+ *    - 2 byte little-endian captured length in bytes
+ *    - 2 byte little-endian original packet length in bytes
+ *  - captured packet bytes
+ *  - optional padding to align to 64 bytes boundary
+ *  - 64 bytes scratch space for the host software
+ */
        __checkReturn   uint8_t *
 ef10_rx_qps_packet_info(
        __in            efx_rxq_t *erp,