Commit d3f9b90b authored by Vladimir Oltean's avatar Vladimir Oltean Committed by David S. Miller

net: dsa: sja1105: Build a minimal understanding of meta frames

Meta frames are sent on the CPU port by the switch if RX timestamping is
enabled. They contain a partial timestamp of the previous frame.

They are Ethernet frames with the Ethernet header constructed out of:

- SJA1105_META_DMAC
- SJA1105_META_SMAC
- ETH_P_SJA1105_META

The Ethernet payload will be decoded in a follow-up patch.
Signed-off-by: default avatarVladimir Oltean <olteanv@gmail.com>
Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 47ed985e
...@@ -12,6 +12,7 @@ ...@@ -12,6 +12,7 @@
#include <net/dsa.h> #include <net/dsa.h>
#define ETH_P_SJA1105 ETH_P_DSA_8021Q #define ETH_P_SJA1105 ETH_P_DSA_8021Q
#define ETH_P_SJA1105_META 0x0008
/* IEEE 802.3 Annex 57A: Slow Protocols PDUs (01:80:C2:xx:xx:xx) */ /* IEEE 802.3 Annex 57A: Slow Protocols PDUs (01:80:C2:xx:xx:xx) */
#define SJA1105_LINKLOCAL_FILTER_A 0x0180C2000000ull #define SJA1105_LINKLOCAL_FILTER_A 0x0180C2000000ull
...@@ -20,6 +21,16 @@ ...@@ -20,6 +21,16 @@
#define SJA1105_LINKLOCAL_FILTER_B 0x011B19000000ull #define SJA1105_LINKLOCAL_FILTER_B 0x011B19000000ull
#define SJA1105_LINKLOCAL_FILTER_B_MASK 0xFFFFFF000000ull #define SJA1105_LINKLOCAL_FILTER_B_MASK 0xFFFFFF000000ull
/* Source and Destination MAC of follow-up meta frames.
* Whereas the choice of SMAC only affects the unique identification of the
* switch as sender of meta frames, the DMAC must be an address that is present
* in the DSA master port's multicast MAC filter.
* 01-80-C2-00-00-0E is a good choice for this, as all profiles of IEEE 1588
* over L2 use this address for some purpose already.
*/
#define SJA1105_META_SMAC 0x222222222222ull
#define SJA1105_META_DMAC 0x0180C200000Eull
struct sja1105_port { struct sja1105_port {
struct dsa_port *dp; struct dsa_port *dp;
bool hwts_tx_en; bool hwts_tx_en;
......
...@@ -22,6 +22,21 @@ static inline bool sja1105_is_link_local(const struct sk_buff *skb) ...@@ -22,6 +22,21 @@ static inline bool sja1105_is_link_local(const struct sk_buff *skb)
return false; return false;
} }
static inline bool sja1105_is_meta_frame(const struct sk_buff *skb)
{
const struct ethhdr *hdr = eth_hdr(skb);
u64 smac = ether_addr_to_u64(hdr->h_source);
u64 dmac = ether_addr_to_u64(hdr->h_dest);
if (smac != SJA1105_META_SMAC)
return false;
if (dmac != SJA1105_META_DMAC)
return false;
if (ntohs(hdr->h_proto) != ETH_P_SJA1105_META)
return false;
return true;
}
/* This is the first time the tagger sees the frame on RX. /* This is the first time the tagger sees the frame on RX.
* Figure out if we can decode it, and if we can, annotate skb->cb with how we * Figure out if we can decode it, and if we can, annotate skb->cb with how we
* plan to do that, so we don't need to check again in the rcv function. * plan to do that, so we don't need to check again in the rcv function.
......
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