summaryrefslogtreecommitdiff
path: root/net/dsa
diff options
context:
space:
mode:
authorChristian Eggers <ceggers@arri.de>2023-01-10 11:49:24 +0300
committerDavid S. Miller <davem@davemloft.net>2023-01-13 11:40:41 +0300
commit90188fff655d8efad79acdf60c3012ffcbbef716 (patch)
treeba4f788ba0e8de376ca8f9614880c9db4b161435 /net/dsa
parent2955762b372b791a8f4cd862cf0b5fef9c456449 (diff)
downloadlinux-90188fff655d8efad79acdf60c3012ffcbbef716.tar.xz
net: dsa: microchip: ptp: add packet reception timestamping
Rx Timestamping is done through 4 additional bytes in tail tag. Whenever the ptp packet is received, the 4 byte hardware time stamped value is added before 1 byte tail tag. Also, bit 7 in tail tag indicates it as PTP frame. This 4 byte value is extracted from the tail tag and reconstructed to absolute time and assigned to skb hwtstamp. If the packet received in PDelay_Resp, then partial ingress timestamp is subtracted from the correction field. Since user space tools expects to be done in hardware. Signed-off-by: Christian Eggers <ceggers@arri.de> Co-developed-by: Arun Ramadoss <arun.ramadoss@microchip.com> Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/dsa')
-rw-r--r--net/dsa/tag_ksz.c25
1 files changed, 19 insertions, 6 deletions
diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
index 420a12853676..6603eaa234d2 100644
--- a/net/dsa/tag_ksz.c
+++ b/net/dsa/tag_ksz.c
@@ -151,10 +151,11 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
* tag0 : Prioritization (not used now)
* tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
*
- * For Egress (KSZ9477 -> Host), 1 byte is added before FCS.
+ * For Egress (KSZ9477 -> Host), 1/5 bytes is added before FCS.
* ---------------------------------------------------------------------------
- * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
* ---------------------------------------------------------------------------
+ * ts : time stamp (Present only if bit 7 of tag0 is set)
* tag0 : zero-based value represents port
* (eg, 0x00=port1, 0x02=port3, 0x06=port7)
*/
@@ -166,6 +167,15 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
#define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
#define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
+static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag)
+{
+ u8 *tstamp_raw = tag - KSZ_PTP_TAG_LEN;
+ ktime_t tstamp;
+
+ tstamp = ksz_decode_tstamp(get_unaligned_be32(tstamp_raw));
+ KSZ_SKB_CB(skb)->tstamp = tstamp;
+}
+
/* Time stamp tag *needs* to be inserted if PTP is enabled in hardware.
* Regardless of Whether it is a PTP frame or not.
*/
@@ -216,8 +226,10 @@ static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
unsigned int len = KSZ_EGRESS_TAG_LEN;
/* Extra 4-bytes PTP timestamp */
- if (tag[0] & KSZ9477_PTP_TAG_INDICATION)
- len += KSZ9477_PTP_TAG_LEN;
+ if (tag[0] & KSZ9477_PTP_TAG_INDICATION) {
+ ksz_rcv_timestamp(skb, tag);
+ len += KSZ_PTP_TAG_LEN;
+ }
return ksz_common_rcv(skb, dev, port, len);
}
@@ -284,10 +296,11 @@ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME);
* tag0 : represents tag override, lookup and valid
* tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
*
- * For rcv, 1 byte is added before FCS.
+ * For rcv, 1/5 bytes is added before FCS.
* ---------------------------------------------------------------------------
- * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
* ---------------------------------------------------------------------------
+ * ts : time stamp (Present only if bit 7 of tag0 is set)
* tag0 : zero-based value represents port
* (eg, 0x00=port1, 0x02=port3, 0x07=port8)
*/