Re: [PATCH v2 5/7] net: dsa: b53: Add logic for RX timestamping
From: Martin Kaistra
Date: Wed Nov 10 2021 - 03:43:42 EST
Am 09.11.21 um 19:07 schrieb Florian Fainelli:
On 11/9/21 1:50 AM, Martin Kaistra wrote:
Packets received by the tagger with opcode=1 contain the 32-bit timestamp
according to the timebase register. This timestamp is saved in
BRCM_SKB_CB(skb)->meta_tstamp. b53_port_rxtstamp() takes this
and puts the full time information from the timecounter into
shwt->hwtstamp.
Signed-off-by: Martin Kaistra <martin.kaistra@xxxxxxxxxxxxx>
---
drivers/net/dsa/b53/b53_common.c | 1 +
drivers/net/dsa/b53/b53_ptp.c | 28 +++++++++++++++++++++++++
drivers/net/dsa/b53/b53_ptp.h | 10 +++++++++
include/linux/dsa/b53.h | 30 +++++++++++++++++++++++++++
net/dsa/tag_brcm.c | 35 ++++++++++++++++++++++++--------
5 files changed, 95 insertions(+), 9 deletions(-)
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index ed590efbd3bf..a9408f9cd414 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -2300,6 +2300,7 @@ static const struct dsa_switch_ops b53_switch_ops = {
.port_max_mtu = b53_get_max_mtu,
.port_change_mtu = b53_change_mtu,
.get_ts_info = b53_get_ts_info,
+ .port_rxtstamp = b53_port_rxtstamp,
};
struct b53_chip_data {
diff --git a/drivers/net/dsa/b53/b53_ptp.c b/drivers/net/dsa/b53/b53_ptp.c
index 8629c510b1a0..f8dd8d484d93 100644
--- a/drivers/net/dsa/b53/b53_ptp.c
+++ b/drivers/net/dsa/b53/b53_ptp.c
@@ -6,6 +6,8 @@
* Copyright (C) 2021 Linutronix GmbH
*/
+#include <linux/ptp_classify.h>
+
#include "b53_priv.h"
#include "b53_ptp.h"
@@ -106,6 +108,32 @@ static long b53_hwtstamp_work(struct ptp_clock_info *ptp)
return B53_PTP_OVERFLOW_PERIOD;
}
+bool b53_port_rxtstamp(struct dsa_switch *ds, int port, struct sk_buff *skb,
+ unsigned int type)
+{
+ struct b53_device *dev = ds->priv;
+ struct b53_port_hwtstamp *ps = &dev->ports[port].port_hwtstamp;
+ struct skb_shared_hwtstamps *shwt;
+ u64 ns;
I had asked you to store b53_port_hwtstamp into dp->priv, any reason for
not doing that?
I am sorry, I must have misunderstood you. tag_brcm.c ist now accessing
b53_port_hwtstamp via dp->priv (like in the sja1105 driver). It should
also be possible, to store it only in there.
+
+ if (type != PTP_CLASS_V2_L2)
+ return false;
+
+ if (!test_bit(B53_HWTSTAMP_ENABLED, &ps->state))
+ return false;
+
+ mutex_lock(&dev->ptp_mutex);
+ ns = timecounter_cyc2time(&dev->tc, BRCM_SKB_CB(skb)->meta_tstamp);
+ mutex_unlock(&dev->ptp_mutex);
+
+ shwt = skb_hwtstamps(skb);
+ memset(shwt, 0, sizeof(*shwt));
+ shwt->hwtstamp = ns_to_ktime(ns);
+
+ return false;
+}
+EXPORT_SYMBOL(b53_port_rxtstamp);
+
int b53_ptp_init(struct b53_device *dev)
{
mutex_init(&dev->ptp_mutex);
diff --git a/drivers/net/dsa/b53/b53_ptp.h b/drivers/net/dsa/b53/b53_ptp.h
index 5cd2fd9621a2..3b3437870c55 100644
--- a/drivers/net/dsa/b53/b53_ptp.h
+++ b/drivers/net/dsa/b53/b53_ptp.h
@@ -9,11 +9,15 @@
#include "b53_priv.h"
+#define SKB_PTP_TYPE(__skb) (*(unsigned int *)((__skb)->cb))
+
#ifdef CONFIG_B53_PTP
int b53_ptp_init(struct b53_device *dev);
void b53_ptp_exit(struct b53_device *dev);
int b53_get_ts_info(struct dsa_switch *ds, int port,
struct ethtool_ts_info *info);
+bool b53_port_rxtstamp(struct dsa_switch *ds, int port, struct sk_buff *skb,
+ unsigned int type);
#else /* !CONFIG_B53_PTP */
static inline int b53_ptp_init(struct b53_device *dev)
@@ -31,5 +35,11 @@ static inline int b53_get_ts_info(struct dsa_switch *ds, int port,
return -EOPNOTSUPP;
}
+static inline bool b53_port_rxtstamp(struct dsa_switch *ds, int port,
+ struct sk_buff *skb, unsigned int type)
+{
+ return false;
+}
+
#endif
#endif
diff --git a/include/linux/dsa/b53.h b/include/linux/dsa/b53.h
index 85aa6d9dc53d..542e5e3040d6 100644
--- a/include/linux/dsa/b53.h
+++ b/include/linux/dsa/b53.h
@@ -46,9 +46,32 @@ struct b53_io_ops {
struct phylink_link_state *state);
};
+/* state flags for b53_port_hwtstamp::state */
+enum {
+ B53_HWTSTAMP_ENABLED,
+ B53_HWTSTAMP_TX_IN_PROGRESS,
+};
+
+struct b53_port_hwtstamp {
+ /* Port index */
+ int port_id;
unsigned int;
+
+ /* Timestamping state */
+ unsigned long state;
+
+ /* Resources for transmit timestamping */
+ unsigned long tx_tstamp_start;
+ struct sk_buff *tx_skb;
+
+ /* Current timestamp configuration */
+ struct hwtstamp_config tstamp_config;
+};
+
struct b53_port {
u16 vlan_ctl_mask;
struct ethtool_eee eee;
+ /* Per-port timestamping resources */
+ struct b53_port_hwtstamp port_hwtstamp;
};
struct b53_vlan {
@@ -112,3 +135,10 @@ struct b53_device {
#define B53_PTP_OVERFLOW_PERIOD (HZ / 2)
struct delayed_work overflow_work;
};
+
+struct brcm_skb_cb {
+ struct sk_buff *clone;
+ u32 meta_tstamp;
+};
+
+#define BRCM_SKB_CB(skb) ((struct brcm_skb_cb *)(skb)->cb)
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 96dbb8ee2fee..d611c1073deb 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -9,6 +9,7 @@
#include <linux/etherdevice.h>
#include <linux/list.h>
#include <linux/slab.h>
+#include <linux/dsa/b53.h>
#include "dsa_priv.h"
@@ -31,7 +32,10 @@
/* 6th byte in the tag */
#define BRCM_LEG_PORT_ID (0xf)
-/* Newer Broadcom tag (4 bytes) */
+/* Newer Broadcom tag (4 bytes)
+ * For egress, when opcode = 0001, additional 4 bytes are used for
+ * the time stamp.
+ */
#define BRCM_TAG_LEN 4
/* Tag is constructed and desconstructed using byte by byte access
@@ -136,19 +140,29 @@ static struct sk_buff *brcm_tag_xmit_ll(struct sk_buff *skb,
*/
static struct sk_buff *brcm_tag_rcv_ll(struct sk_buff *skb,
struct net_device *dev,
- unsigned int offset)
+ unsigned int offset,
+ int *tag_len)
unsigned int tag_len.