The PTP time of the switch is not preserved when uploading a new static
configuration. Work around this hardware oddity by reading its PTP time
before a static config upload, and restoring it afterwards.
Static config changes are expected to occur at runtime even in scenarios
directly related to PTP, i.e. the Time-Aware Scheduler of the switch is
programmed in this way.
Signed-off-by: Vladimir Oltean <olte...@gmail.com>
---
Changes since RFC:
- None.
drivers/net/dsa/sja1105/sja1105_main.c | 32 ++++++++++++-
drivers/net/dsa/sja1105/sja1105_ptp.c | 66 ++++++++++++++++++--------
drivers/net/dsa/sja1105/sja1105_ptp.h | 25 ++++++++++
drivers/net/dsa/sja1105/sja1105_spi.c | 4 --
4 files changed, 101 insertions(+), 26 deletions(-)
diff --git a/drivers/net/dsa/sja1105/sja1105_main.c
b/drivers/net/dsa/sja1105/sja1105_main.c
index f7f03d486499..abb22f0a9884 100644
--- a/drivers/net/dsa/sja1105/sja1105_main.c
+++ b/drivers/net/dsa/sja1105/sja1105_main.c
@@ -1382,8 +1382,13 @@ static void sja1105_bridge_leave(struct dsa_switch *ds,
int port,
*/
static int sja1105_static_config_reload(struct sja1105_private *priv)
{
+ struct ptp_system_timestamp ptp_sts_before;
+ struct ptp_system_timestamp ptp_sts_after;
struct sja1105_mac_config_entry *mac;
int speed_mbps[SJA1105_NUM_PORTS];
+ s64 t1, t2, t3, t4;
+ s64 ptpclkval;
+ s64 t12, t34;
int rc, i;
mac = priv->static_config.tables[BLK_IDX_MAC_CONFIG].entries;
@@ -1398,10 +1403,35 @@ static int sja1105_static_config_reload(struct
sja1105_private *priv)
mac[i].speed = SJA1105_SPEED_AUTO;
}
+ /* No PTP operations can run right now */
+ mutex_lock(&priv->ptp_lock);
+
+ ptpclkval = __sja1105_ptp_gettimex(priv, &ptp_sts_before);
+
/* Reset switch and send updated static configuration */
rc = sja1105_static_config_upload(priv);
if (rc < 0)
- goto out;
+ goto out_unlock_ptp;
+
+ rc = __sja1105_ptp_settime(priv, 0, &ptp_sts_after);
+ if (rc < 0)
+ goto out_unlock_ptp;
+
+ t1 = timespec64_to_ns(&ptp_sts_before.pre_ts);
+ t2 = timespec64_to_ns(&ptp_sts_before.post_ts);
+ t3 = timespec64_to_ns(&ptp_sts_after.pre_ts);
+ t4 = timespec64_to_ns(&ptp_sts_after.post_ts);
+ /* Mid point, corresponds to pre-reset PTPCLKVAL */
+ t12 = t1 + (t2 - t1) / 2;
+ /* Mid point, corresponds to post-reset PTPCLKVAL, aka 0 */
+ t34 = t3 + (t4 - t3) / 2;
+ /* Advance PTPCLKVAL by the time it took since its readout */
+ ptpclkval += (t34 - t12);
+
+ __sja1105_ptp_adjtime(priv, ptpclkval);
+
+out_unlock_ptp:
+ mutex_unlock(&priv->ptp_lock);
/* Configure the CGU (PLLs) for MII and RMII PHYs.
* For these interfaces there is no dynamic configuration
diff --git a/drivers/net/dsa/sja1105/sja1105_ptp.c
b/drivers/net/dsa/sja1105/sja1105_ptp.c
index 04693c702b09..a7722c0944fb 100644
--- a/drivers/net/dsa/sja1105/sja1105_ptp.c
+++ b/drivers/net/dsa/sja1105/sja1105_ptp.c
@@ -215,17 +215,26 @@ int sja1105_ptp_reset(struct sja1105_private *priv)
return rc;
}
+/* Caller must hold priv->ptp_lock */
+u64 __sja1105_ptp_gettimex(struct sja1105_private *priv,
+ struct ptp_system_timestamp *sts)
+{
+ u64 ticks;
+
+ ticks = sja1105_ptpclkval_read(priv, sts);
+
+ return sja1105_ticks_to_ns(ticks);
+}
+
static int sja1105_ptp_gettimex(struct ptp_clock_info *ptp,
struct timespec64 *ts,
struct ptp_system_timestamp *sts)
{
struct sja1105_private *priv = ptp_to_sja1105(ptp);
- u64 ticks;
mutex_lock(&priv->ptp_lock);
- ticks = sja1105_ptpclkval_read(priv, sts);
- *ts = ns_to_timespec64(sja1105_ticks_to_ns(ticks));
+ *ts = ns_to_timespec64(__sja1105_ptp_gettimex(priv, sts));
mutex_unlock(&priv->ptp_lock);
@@ -245,33 +254,42 @@ static int sja1105_ptp_mode_set(struct sja1105_private
*priv,
}
/* Caller must hold priv->ptp_lock */
-static int sja1105_ptpclkval_write(struct sja1105_private *priv, u64 val)
+static int sja1105_ptpclkval_write(struct sja1105_private *priv, u64 val,
+ struct ptp_system_timestamp *ptp_sts)
{
const struct sja1105_regs *regs = priv->info->regs;
return sja1105_spi_send_int(priv, SPI_WRITE, regs->ptpclk, &val, 8,
- NULL);
+ ptp_sts);
}
/* Write to PTPCLKVAL while PTPCLKADD is 0 */
-static int sja1105_ptp_settime(struct ptp_clock_info *ptp,
- const struct timespec64 *ts)
+int __sja1105_ptp_settime(struct sja1105_private *priv, u64 ns,
+ struct ptp_system_timestamp *ptp_sts)
{
- u64 ticks = ns_to_sja1105_ticks(timespec64_to_ns(ts));
- struct sja1105_private *priv = ptp_to_sja1105(ptp);
+ u64 ticks = ns_to_sja1105_ticks(ns);
int rc;
- mutex_lock(&priv->ptp_lock);
-
rc = sja1105_ptp_mode_set(priv, PTP_SET_MODE);
if (rc < 0) {
dev_err(priv->ds->dev, "Failed to put PTPCLK in set mode\n");
- goto out;
+ return rc;
}
- rc = sja1105_ptpclkval_write(priv, ticks);
+ return sja1105_ptpclkval_write(priv, ticks, ptp_sts);
+}
+
+static int sja1105_ptp_settime(struct ptp_clock_info *ptp,
+ const struct timespec64 *ts)
+{
+ struct sja1105_private *priv = ptp_to_sja1105(ptp);
+ u64 ns = timespec64_to_ns(ts);
+ int rc;
+
+ mutex_lock(&priv->ptp_lock);
+
+ rc = __sja1105_ptp_settime(priv, ns, NULL);
-out:
mutex_unlock(&priv->ptp_lock);
return rc;
@@ -320,23 +338,29 @@ u64 sja1105_ptpclkval_read(struct sja1105_private *priv,
}
/* Write to PTPCLKVAL while PTPCLKADD is 1 */
-static int sja1105_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+int __sja1105_ptp_adjtime(struct sja1105_private *priv, s64 delta)
{
- struct sja1105_private *priv = ptp_to_sja1105(ptp);
s64 ticks = ns_to_sja1105_ticks(delta);
int rc;
- mutex_lock(&priv->ptp_lock);
-
rc = sja1105_ptp_mode_set(priv, PTP_ADD_MODE);
if (rc < 0) {
dev_err(priv->ds->dev, "Failed to put PTPCLK in add mode\n");
- goto out;
+ return rc;
}
- rc = sja1105_ptpclkval_write(priv, ticks);
+ return sja1105_ptpclkval_write(priv, ticks, NULL);
+}
+
+static int sja1105_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+ struct sja1105_private *priv = ptp_to_sja1105(ptp);
+ int rc;
+
+ mutex_lock(&priv->ptp_lock);
+
+ rc = __sja1105_ptp_adjtime(priv, delta);
-out:
mutex_unlock(&priv->ptp_lock);
return rc;
diff --git a/drivers/net/dsa/sja1105/sja1105_ptp.h
b/drivers/net/dsa/sja1105/sja1105_ptp.h
index 80c33e5e4503..c699611e585d 100644
--- a/drivers/net/dsa/sja1105/sja1105_ptp.h
+++ b/drivers/net/dsa/sja1105/sja1105_ptp.h
@@ -42,6 +42,14 @@ int sja1105_ptp_reset(struct sja1105_private *priv);
u64 sja1105_ptpclkval_read(struct sja1105_private *priv,
struct ptp_system_timestamp *sts);
+u64 __sja1105_ptp_gettimex(struct sja1105_private *priv,
+ struct ptp_system_timestamp *sts);
+
+int __sja1105_ptp_settime(struct sja1105_private *priv, u64 ns,
+ struct ptp_system_timestamp *ptp_sts);
+
+int __sja1105_ptp_adjtime(struct sja1105_private *priv, s64 delta);
+
#else
static inline int sja1105_ptp_clock_register(struct sja1105_private *priv)
@@ -77,6 +85,23 @@ static inline u64 sja1105_ptpclkval_read(struct
sja1105_private *priv,
return 0;
}
+static inline u64 __sja1105_ptp_gettimex(struct sja1105_private *priv,
+ struct ptp_system_timestamp *sts)
+{
+ return 0;
+}
+
+static inline int __sja1105_ptp_settime(struct sja1105_private *priv, u64 ns,
+ struct ptp_system_timestamp *ptp_sts)
+{
+ return 0;
+}
+
+static inline int __sja1105_ptp_adjtime(struct sja1105_private *priv, s64
delta)
+{
+ return 0;
+}
+
#define sja1105et_ptp_cmd NULL
#define sja1105pqrs_ptp_cmd NULL
diff --git a/drivers/net/dsa/sja1105/sja1105_spi.c
b/drivers/net/dsa/sja1105/sja1105_spi.c
index 26985f1209ad..eae9c9baa189 100644
--- a/drivers/net/dsa/sja1105/sja1105_spi.c
+++ b/drivers/net/dsa/sja1105/sja1105_spi.c
@@ -496,10 +496,6 @@ int sja1105_static_config_upload(struct sja1105_private
*priv)
dev_info(dev, "Succeeded after %d tried\n", RETRIES - retries);
}
- rc = sja1105_ptp_reset(priv);
- if (rc < 0)
- dev_err(dev, "Failed to reset PTP clock: %d\n", rc);
-
dev_info(dev, "Reset switch and programmed static config\n");
out:
--
2.17.1
