Meta frame reception relies on the hardware keeping its promise that it will send no other traffic towards the CPU port between a link-local frame and a meta frame. Otherwise there is no other way to associate the meta frame with the link-local frame it's holding a timestamp of. The receive function is made stateful, and buffers a timestampable frame until its meta frame arrives, then merges the two, drops the meta and releases the link-local frame up the stack.
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| @@ -45,6 +45,13 @@ struct sja1105_tagger_data { · 44 unmodified lines | |||
| 45 | bool hwts_rx_en; | 45 | bool hwts_rx_en; |
| 46 | }; | 46 | }; |
| 47 | 47 | ||
| 48 | struct sja1105_skb_cb { | ||
| 49 | u32 meta_tstamp; | ||
| 50 | }; | ||
| 51 | |||
| 52 | #define SJA1105_SKB_CB(skb) \ | ||
| 53 | ((struct sja1105_skb_cb *)DSA_SKB_CB_PRIV(skb)) | ||
| 54 | |||
| 48 | struct sja1105_port { | 55 | struct sja1105_port { |
| 49 | struct sja1105_tagger_data *data; | 56 | struct sja1105_tagger_data *data; |
| 50 | struct dsa_port *dp; | 57 | struct dsa_port *dp; |