[PATCH v4 00/13] net: ethernet: ti: cpts: update and fixes

[PATCH v4 00/13] net: ethernet: ti: cpts: update and fixes

[Grygorii Strashko]

It is preparation series intended to clean up and optimize TI CPTS driver to
facilitate further integration with other TI's SoCs like Keystone 2.

Changes in v4:
- fixed build error in patch
  "net: ethernet: ti: cpts: clean up event list if event pool is empty"
- rebased on top of net-next
 
Changes in v3:
- patches reordered: fixes and small updates moved first
- added comments in code about cpts->cc_mult
- conversation range (maxsec) limited to 10sec

Changes in v2:
- patch "net: ethernet: ti: cpts: rework initialization/deinitialization"
  was split on 4 patches
- applied comments from Richard Cochran
- dropped patch
  "net: ethernet: ti: cpts: add return value to tx and rx timestamp funcitons"
- new patches added:
  "net: ethernet: ti: cpts: drop excessive writes to CTRL and INT_EN regs"
  and "clocksource: export the clocks_calc_mult_shift to use by timestamp code"

Links on prev versions:
v3: https://www.spinics.net/lists/devicetree/msg153474.html
v2: http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1282034.html
v1: http://www.spinics.net/lists/linux-omap/msg131925.html

Grygorii Strashko (11):
  net: ethernet: ti: cpts: switch to readl/writel_relaxed()
  net: ethernet: ti: allow cpts to be built separately
  net: ethernet: ti: cpsw: minimize direct access to struct cpts
  net: ethernet: ti: cpts: fix unbalanced clk api usage in cpts_register/unregister
  net: ethernet: ti: cpts: fix registration order
  net: ethernet: ti: cpts: disable cpts when unregistered
  net: ethernet: ti: cpts: drop excessive writes to CTRL and INT_EN regs
  net: ethernet: ti: cpts: rework initialization/deinitialization
  net: ethernet: ti: cpts: move dt props parsing to cpts driver
  net: ethernet: ti: cpts: calc mult and shift from refclk freq
  net: ethernet: ti: cpts: fix overflow check period

Murali Karicheri (1):
  clocksource: export the clocks_calc_mult_shift to use by timestamp code

WingMan Kwok (1):
  net: ethernet: ti: cpts: clean up event list if event pool is empty

 Documentation/devicetree/bindings/net/cpsw.txt |   8 +-
 drivers/net/ethernet/ti/Kconfig                |   2 +-
 drivers/net/ethernet/ti/Makefile               |   3 +-
 drivers/net/ethernet/ti/cpsw.c                 |  84 ++++-----
 drivers/net/ethernet/ti/cpsw.h                 |   2 -
 drivers/net/ethernet/ti/cpts.c                 | 239 +++++++++++++++++++------
 drivers/net/ethernet/ti/cpts.h                 |  80 ++++++++-
 kernel/time/clocksource.c                      |   1 +
 8 files changed, 304 insertions(+), 115 deletions(-)

-- 
2.10.1

[PATCH v4 01/13] net: ethernet: ti: cpts: switch to readl/writel_relaxed()

[Grygorii Strashko]

Switch to readl/writel_relaxed() APIs, because this is recommended
API and the CPTS IP is reused on Keystone 2 SoCs
where LE/BE modes are supported.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
---
 drivers/net/ethernet/ti/cpts.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 85a55b4..a42c449 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -33,8 +33,8 @@
 
 #ifdef CONFIG_TI_CPTS
 
-#define cpts_read32(c, r)	__raw_readl(&c->reg->r)
-#define cpts_write32(c, v, r)	__raw_writel(v, &c->reg->r)
+#define cpts_read32(c, r)	readl_relaxed(&c->reg->r)
+#define cpts_write32(c, v, r)	writel_relaxed(v, &c->reg->r)
 
 static int event_expired(struct cpts_event *event)
 {
-- 
2.10.1

[PATCH v4 02/13] net: ethernet: ti: allow cpts to be built separately

[Grygorii Strashko]

TI CPTS IP is used as part of TI OMAP CPSW driver, but it's also
present as part of NETCP on TI Keystone 2 SoCs. So, It's required
to enable build of CPTS for both this drivers and this can be
achieved by allowing CPTS to be built separately.

Hence, allow cpts to be built separately and convert it to be
a module as both CPSW and NETCP drives can be built as modules.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/Kconfig  |  2 +-
 drivers/net/ethernet/ti/Makefile |  3 ++-
 drivers/net/ethernet/ti/cpsw.c   | 22 +++++++++++++++++-----
 drivers/net/ethernet/ti/cpts.c   | 16 ++++++++--------
 drivers/net/ethernet/ti/cpts.h   | 18 ++++++++++++++----
 5 files changed, 42 insertions(+), 19 deletions(-)

diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
index 9904d74..ff7f518 100644
--- a/drivers/net/ethernet/ti/Kconfig
+++ b/drivers/net/ethernet/ti/Kconfig
@@ -74,7 +74,7 @@ config TI_CPSW
 	  will be called cpsw.
 
 config TI_CPTS
-	bool "TI Common Platform Time Sync (CPTS) Support"
+	tristate "TI Common Platform Time Sync (CPTS) Support"
 	depends on TI_CPSW
 	select PTP_1588_CLOCK
 	---help---
diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
index d420d94..1e7c10b 100644
--- a/drivers/net/ethernet/ti/Makefile
+++ b/drivers/net/ethernet/ti/Makefile
@@ -12,8 +12,9 @@ obj-$(CONFIG_TI_DAVINCI_MDIO) += davinci_mdio.o
 obj-$(CONFIG_TI_DAVINCI_CPDMA) += davinci_cpdma.o
 obj-$(CONFIG_TI_CPSW_PHY_SEL) += cpsw-phy-sel.o
 obj-$(CONFIG_TI_CPSW_ALE) += cpsw_ale.o
+obj-$(CONFIG_TI_CPTS) += cpts.o
 obj-$(CONFIG_TI_CPSW) += ti_cpsw.o
-ti_cpsw-y := cpsw.o cpts.o
+ti_cpsw-y := cpsw.o
 
 obj-$(CONFIG_TI_KEYSTONE_NETCP) += keystone_netcp.o
 keystone_netcp-y := netcp_core.o
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 3f96c57..323174d 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1594,7 +1594,7 @@ static netdev_tx_t cpsw_ndo_start_xmit(struct sk_buff *skb,
 	return NETDEV_TX_BUSY;
 }
 
-#ifdef CONFIG_TI_CPTS
+#if IS_ENABLED(CONFIG_TI_CPTS)
 
 static void cpsw_hwtstamp_v1(struct cpsw_common *cpsw)
 {
@@ -1742,7 +1742,16 @@ static int cpsw_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
 
 	return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ? -EFAULT : 0;
 }
+#else
+static int cpsw_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
+{
+	return -EOPNOTSUPP;
+}
 
+static int cpsw_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
+{
+	return -EOPNOTSUPP;
+}
 #endif /*CONFIG_TI_CPTS*/
 
 static int cpsw_ndo_ioctl(struct net_device *dev, struct ifreq *req, int cmd)
@@ -1755,12 +1764,10 @@ static int cpsw_ndo_ioctl(struct net_device *dev, struct ifreq *req, int cmd)
 		return -EINVAL;
 
 	switch (cmd) {
-#ifdef CONFIG_TI_CPTS
 	case SIOCSHWTSTAMP:
 		return cpsw_hwtstamp_set(dev, req);
 	case SIOCGHWTSTAMP:
 		return cpsw_hwtstamp_get(dev, req);
-#endif
 	}
 
 	if (!cpsw->slaves[slave_no].phy)
@@ -2100,10 +2107,10 @@ static void cpsw_set_msglevel(struct net_device *ndev, u32 value)
 	priv->msg_enable = value;
 }
 
+#if IS_ENABLED(CONFIG_TI_CPTS)
 static int cpsw_get_ts_info(struct net_device *ndev,
 			    struct ethtool_ts_info *info)
 {
-#ifdef CONFIG_TI_CPTS
 	struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
 
 	info->so_timestamping =
@@ -2120,7 +2127,12 @@ static int cpsw_get_ts_info(struct net_device *ndev,
 	info->rx_filters =
 		(1 << HWTSTAMP_FILTER_NONE) |
 		(1 << HWTSTAMP_FILTER_PTP_V2_EVENT);
+	return 0;
+}
 #else
+static int cpsw_get_ts_info(struct net_device *ndev,
+			    struct ethtool_ts_info *info)
+{
 	info->so_timestamping =
 		SOF_TIMESTAMPING_TX_SOFTWARE |
 		SOF_TIMESTAMPING_RX_SOFTWARE |
@@ -2128,9 +2140,9 @@ static int cpsw_get_ts_info(struct net_device *ndev,
 	info->phc_index = -1;
 	info->tx_types = 0;
 	info->rx_filters = 0;
-#endif
 	return 0;
 }
+#endif
 
 static int cpsw_get_link_ksettings(struct net_device *ndev,
 				   struct ethtool_link_ksettings *ecmd)
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index a42c449..8cb0369 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -31,8 +31,6 @@
 
 #include "cpts.h"
 
-#ifdef CONFIG_TI_CPTS
-
 #define cpts_read32(c, r)	readl_relaxed(&c->reg->r)
 #define cpts_write32(c, v, r)	writel_relaxed(v, &c->reg->r)
 
@@ -334,6 +332,7 @@ void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 	memset(ssh, 0, sizeof(*ssh));
 	ssh->hwtstamp = ns_to_ktime(ns);
 }
+EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
 
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
@@ -349,13 +348,11 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 	ssh.hwtstamp = ns_to_ktime(ns);
 	skb_tstamp_tx(skb, &ssh);
 }
-
-#endif /*CONFIG_TI_CPTS*/
+EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
 
 int cpts_register(struct device *dev, struct cpts *cpts,
 		  u32 mult, u32 shift)
 {
-#ifdef CONFIG_TI_CPTS
 	int err, i;
 	unsigned long flags;
 
@@ -391,18 +388,21 @@ int cpts_register(struct device *dev, struct cpts *cpts,
 	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
 
 	cpts->phc_index = ptp_clock_index(cpts->clock);
-#endif
 	return 0;
 }
+EXPORT_SYMBOL_GPL(cpts_register);
 
 void cpts_unregister(struct cpts *cpts)
 {
-#ifdef CONFIG_TI_CPTS
 	if (cpts->clock) {
 		ptp_clock_unregister(cpts->clock);
 		cancel_delayed_work_sync(&cpts->overflow_work);
 	}
 	if (cpts->refclk)
 		cpts_clk_release(cpts);
-#endif
 }
+EXPORT_SYMBOL_GPL(cpts_unregister);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TI CPTS driver");
+MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index 69a46b9..416ba2c 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -111,7 +111,7 @@ struct cpts {
 	struct cpsw_cpts __iomem *reg;
 	int tx_enable;
 	int rx_enable;
-#ifdef CONFIG_TI_CPTS
+#if IS_ENABLED(CONFIG_TI_CPTS)
 	struct ptp_clock_info info;
 	struct ptp_clock *clock;
 	spinlock_t lock; /* protects time registers */
@@ -127,9 +127,11 @@ struct cpts {
 #endif
 };
 
-#ifdef CONFIG_TI_CPTS
+#if IS_ENABLED(CONFIG_TI_CPTS)
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb);
+int cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift);
+void cpts_unregister(struct cpts *cpts);
 #else
 static inline void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
@@ -137,9 +139,17 @@ static inline void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 static inline void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 }
+
+static inline int
+cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift)
+{
+	return 0;
+}
+
+static inline void cpts_unregister(struct cpts *cpts)
+{
+}
 #endif
 
-int cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift);
-void cpts_unregister(struct cpts *cpts);
 
 #endif
-- 
2.10.1

[PATCH v4 03/13] net: ethernet: ti: cpsw: minimize direct access to struct cpts

[Grygorii Strashko]

This will provide more flexibility in changing CPTS internals and also
required for further changes.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpsw.c | 28 +++++++++++++++-------------
 drivers/net/ethernet/ti/cpts.h | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index 323174d..ec05e20 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1562,7 +1562,7 @@ static netdev_tx_t cpsw_ndo_start_xmit(struct sk_buff *skb,
 	}
 
 	if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP &&
-				cpsw->cpts->tx_enable)
+	    cpts_is_tx_enabled(cpsw->cpts))
 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
 
 	skb_tx_timestamp(skb);
@@ -1601,7 +1601,8 @@ static void cpsw_hwtstamp_v1(struct cpsw_common *cpsw)
 	struct cpsw_slave *slave = &cpsw->slaves[cpsw->data.active_slave];
 	u32 ts_en, seq_id;
 
-	if (!cpsw->cpts->tx_enable && !cpsw->cpts->rx_enable) {
+	if (!cpts_is_tx_enabled(cpsw->cpts) &&
+	    !cpts_is_rx_enabled(cpsw->cpts)) {
 		slave_write(slave, 0, CPSW1_TS_CTL);
 		return;
 	}
@@ -1609,10 +1610,10 @@ static void cpsw_hwtstamp_v1(struct cpsw_common *cpsw)
 	seq_id = (30 << CPSW_V1_SEQ_ID_OFS_SHIFT) | ETH_P_1588;
 	ts_en = EVENT_MSG_BITS << CPSW_V1_MSG_TYPE_OFS;
 
-	if (cpsw->cpts->tx_enable)
+	if (cpts_is_tx_enabled(cpsw->cpts))
 		ts_en |= CPSW_V1_TS_TX_EN;
 
-	if (cpsw->cpts->rx_enable)
+	if (cpts_is_rx_enabled(cpsw->cpts))
 		ts_en |= CPSW_V1_TS_RX_EN;
 
 	slave_write(slave, ts_en, CPSW1_TS_CTL);
@@ -1635,20 +1636,20 @@ static void cpsw_hwtstamp_v2(struct cpsw_priv *priv)
 	case CPSW_VERSION_2:
 		ctrl &= ~CTRL_V2_ALL_TS_MASK;
 
-		if (cpsw->cpts->tx_enable)
+		if (cpts_is_tx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V2_TX_TS_BITS;
 
-		if (cpsw->cpts->rx_enable)
+		if (cpts_is_rx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V2_RX_TS_BITS;
 		break;
 	case CPSW_VERSION_3:
 	default:
 		ctrl &= ~CTRL_V3_ALL_TS_MASK;
 
-		if (cpsw->cpts->tx_enable)
+		if (cpts_is_tx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V3_TX_TS_BITS;
 
-		if (cpsw->cpts->rx_enable)
+		if (cpts_is_rx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V3_RX_TS_BITS;
 		break;
 	}
@@ -1684,7 +1685,7 @@ static int cpsw_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 
 	switch (cfg.rx_filter) {
 	case HWTSTAMP_FILTER_NONE:
-		cpts->rx_enable = 0;
+		cpts_rx_enable(cpts, 0);
 		break;
 	case HWTSTAMP_FILTER_ALL:
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
@@ -1700,14 +1701,14 @@ static int cpsw_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
-		cpts->rx_enable = 1;
+		cpts_rx_enable(cpts, 1);
 		cfg.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
 		break;
 	default:
 		return -ERANGE;
 	}
 
-	cpts->tx_enable = cfg.tx_type == HWTSTAMP_TX_ON;
+	cpts_tx_enable(cpts, cfg.tx_type == HWTSTAMP_TX_ON);
 
 	switch (cpsw->version) {
 	case CPSW_VERSION_1:
@@ -1736,8 +1737,9 @@ static int cpsw_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
 		return -EOPNOTSUPP;
 
 	cfg.flags = 0;
-	cfg.tx_type = cpts->tx_enable ? HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
-	cfg.rx_filter = (cpts->rx_enable ?
+	cfg.tx_type = cpts_is_tx_enabled(cpts) ?
+		      HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
+	cfg.rx_filter = (cpts_is_rx_enabled(cpts) ?
 			 HWTSTAMP_FILTER_PTP_V2_EVENT : HWTSTAMP_FILTER_NONE);
 
 	return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ? -EFAULT : 0;
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index 416ba2c..29a1e80c 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -132,6 +132,27 @@ void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 int cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift);
 void cpts_unregister(struct cpts *cpts);
+
+static inline void cpts_rx_enable(struct cpts *cpts, int enable)
+{
+	cpts->rx_enable = enable;
+}
+
+static inline bool cpts_is_rx_enabled(struct cpts *cpts)
+{
+	return !!cpts->rx_enable;
+}
+
+static inline void cpts_tx_enable(struct cpts *cpts, int enable)
+{
+	cpts->tx_enable = enable;
+}
+
+static inline bool cpts_is_tx_enabled(struct cpts *cpts)
+{
+	return !!cpts->tx_enable;
+}
+
 #else
 static inline void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
@@ -149,6 +170,24 @@ cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift)
 static inline void cpts_unregister(struct cpts *cpts)
 {
 }
+
+static inline void cpts_rx_enable(struct cpts *cpts, int enable)
+{
+}
+
+static inline bool cpts_is_rx_enabled(struct cpts *cpts)
+{
+	return false;
+}
+
+static inline void cpts_tx_enable(struct cpts *cpts, int enable)
+{
+}
+
+static inline bool cpts_is_tx_enabled(struct cpts *cpts)
+{
+	return false;
+}
 #endif
 
 
-- 
2.10.1

[PATCH v4 04/13] net: ethernet: ti: cpts: fix unbalanced clk api usage in cpts_register/unregister

[Grygorii Strashko]

There are two issues with TI CPTS code which are reproducible when TI
CPSW ethX device passes few up/down iterations:
- cpts refclk prepare counter continuously incremented after each
up/down iteration;
- devm_clk_get(dev, "cpts") is called many times.

Hence, fix these issues by using clk_disable_unprepare() in
cpts_clk_release() and skipping devm_clk_get() if cpts refclk has been
acquired already.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
---
 drivers/net/ethernet/ti/cpts.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 8cb0369..61198f1 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -230,18 +230,20 @@ static void cpts_overflow_check(struct work_struct *work)
 
 static void cpts_clk_init(struct device *dev, struct cpts *cpts)
 {
-	cpts->refclk = devm_clk_get(dev, "cpts");
-	if (IS_ERR(cpts->refclk)) {
-		dev_err(dev, "Failed to get cpts refclk\n");
-		cpts->refclk = NULL;
-		return;
+	if (!cpts->refclk) {
+		cpts->refclk = devm_clk_get(dev, "cpts");
+		if (IS_ERR(cpts->refclk)) {
+			dev_err(dev, "Failed to get cpts refclk\n");
+			cpts->refclk = NULL;
+			return;
+		}
 	}
 	clk_prepare_enable(cpts->refclk);
 }
 
 static void cpts_clk_release(struct cpts *cpts)
 {
-	clk_disable(cpts->refclk);
+	clk_disable_unprepare(cpts->refclk);
 }
 
 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
-- 
2.10.1

[PATCH v4 05/13] net: ethernet: ti: cpts: fix registration order

[Grygorii Strashko]

The ptp clock registered before spinlock, which is protecting it, and
before timecounter and cyclecounter initialization in cpts_register().

So, ensure that ptp clock is registered the last, after everything
else is done.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
---
 drivers/net/ethernet/ti/cpts.c | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 61198f1..3dda6d5 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -356,15 +356,8 @@ int cpts_register(struct device *dev, struct cpts *cpts,
 		  u32 mult, u32 shift)
 {
 	int err, i;
-	unsigned long flags;
 
 	cpts->info = cpts_info;
-	cpts->clock = ptp_clock_register(&cpts->info, dev);
-	if (IS_ERR(cpts->clock)) {
-		err = PTR_ERR(cpts->clock);
-		cpts->clock = NULL;
-		return err;
-	}
 	spin_lock_init(&cpts->lock);
 
 	cpts->cc.read = cpts_systim_read;
@@ -382,15 +375,26 @@ int cpts_register(struct device *dev, struct cpts *cpts,
 	cpts_write32(cpts, CPTS_EN, control);
 	cpts_write32(cpts, TS_PEND_EN, int_enable);
 
-	spin_lock_irqsave(&cpts->lock, flags);
 	timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
-	spin_unlock_irqrestore(&cpts->lock, flags);
 
 	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
-	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
 
+	cpts->clock = ptp_clock_register(&cpts->info, dev);
+	if (IS_ERR(cpts->clock)) {
+		err = PTR_ERR(cpts->clock);
+		cpts->clock = NULL;
+		goto err_ptp;
+	}
 	cpts->phc_index = ptp_clock_index(cpts->clock);
+
+	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
+
 	return 0;
+
+err_ptp:
+	if (cpts->refclk)
+		cpts_clk_release(cpts);
+	return err;
 }
 EXPORT_SYMBOL_GPL(cpts_register);
 
-- 
2.10.1

[PATCH v4 06/13] net: ethernet: ti: cpts: disable cpts when unregistered

[Grygorii Strashko]

The cpts now is left enabled after unregistration.
Hence, disable it in cpts_unregister().

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
---
 drivers/net/ethernet/ti/cpts.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 3dda6d5..d3c1ac5 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -404,6 +404,10 @@ void cpts_unregister(struct cpts *cpts)
 		ptp_clock_unregister(cpts->clock);
 		cancel_delayed_work_sync(&cpts->overflow_work);
 	}
+
+	cpts_write32(cpts, 0, int_enable);
+	cpts_write32(cpts, 0, control);
+
 	if (cpts->refclk)
 		cpts_clk_release(cpts);
 }
-- 
2.10.1

[PATCH v4 07/13] net: ethernet: ti: cpts: clean up event list if event pool is empty

[Grygorii Strashko]

From: WingMan Kwok <w-kwok2@ti.com>

When a CPTS user does not exit gracefully by disabling cpts
timestamping and leaving a joined multicast group, the system
continues to receive and timestamps the ptp packets which eventually
occupy all the event list entries.  When this happns, the added code
tries to remove some list entries which are expired.

Signed-off-by: WingMan Kwok <w-kwok2@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpts.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index d3c1ac5..7ab1fa7 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -57,6 +57,26 @@ static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
 	return -1;
 }
 
+static int cpts_purge_events(struct cpts *cpts)
+{
+	struct list_head *this, *next;
+	struct cpts_event *event;
+	int removed = 0;
+
+	list_for_each_safe(this, next, &cpts->events) {
+		event = list_entry(this, struct cpts_event, list);
+		if (event_expired(event)) {
+			list_del_init(&event->list);
+			list_add(&event->list, &cpts->pool);
+			++removed;
+		}
+	}
+
+	if (removed)
+		pr_debug("cpts: event pool cleaned up %d\n", removed);
+	return removed ? 0 : -1;
+}
+
 /*
  * Returns zero if matching event type was found.
  */
@@ -69,10 +89,12 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 	for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
 		if (cpts_fifo_pop(cpts, &hi, &lo))
 			break;
-		if (list_empty(&cpts->pool)) {
-			pr_err("cpts: event pool is empty\n");
+
+		if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
+			pr_err("cpts: event pool empty\n");
 			return -1;
 		}
+
 		event = list_first_entry(&cpts->pool, struct cpts_event, list);
 		event->tmo = jiffies + 2;
 		event->high = hi;
-- 
2.10.1

[PATCH v4 08/13] net: ethernet: ti: cpts: drop excessive writes to CTRL and INT_EN regs

[Grygorii Strashko]

CPTS module and IRQs are always enabled when CPTS is registered,
before starting overflow check work, and disabled during
deregistration, when overflow check work has been canceled already.
So, It doesn't require to (re)enable CPTS module and IRQs in
cpts_overflow_check().

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
---
 drivers/net/ethernet/ti/cpts.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 7ab1fa7..fe1bb7f 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -243,8 +243,6 @@ static void cpts_overflow_check(struct work_struct *work)
 	struct timespec64 ts;
 	struct cpts *cpts = container_of(work, struct cpts, overflow_work.work);
 
-	cpts_write32(cpts, CPTS_EN, control);
-	cpts_write32(cpts, TS_PEND_EN, int_enable);
 	cpts_ptp_gettime(&cpts->info, &ts);
 	pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
 	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
-- 
2.10.1

[PATCH v4 09/13] net: ethernet: ti: cpts: rework initialization/deinitialization

[Grygorii Strashko]

The current implementation CPTS initialization and deinitialization
(represented by cpts_register/unregister()) does too many static
initialization from .ndo_open(), which is reasonable to do once at probe
time instead, and also require caller to allocate memory for struct cpts,
which is internal for CPTS driver in general.

This patch splits CPTS initialization and deinitialization on two parts:

- static initializtion cpts_create()/cpts_release() which expected to be
executed when parent driver is probed/removed;

- dynamic part cpts_register/unregister() which expected to be executed
when network device is opened/closed.

As result, current code of CPTS parent driver - CPSW - will be simplified
(and it also will allow simplify adding support for Keystone 2 devices in
the future), plus more initialization errors will be catched earlier. In
addition, this change allows to clean up cpts.h for the case when CPTS is
disabled.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpsw.c |  24 +++++-----
 drivers/net/ethernet/ti/cpts.c | 102 ++++++++++++++++++++++++-----------------
 drivers/net/ethernet/ti/cpts.h |  26 +++++++++--
 3 files changed, 95 insertions(+), 57 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index ec05e20..deb008a 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -1486,9 +1486,7 @@ static int cpsw_ndo_open(struct net_device *ndev)
 		if (ret < 0)
 			goto err_cleanup;
 
-		if (cpts_register(cpsw->dev, cpsw->cpts,
-				  cpsw->data.cpts_clock_mult,
-				  cpsw->data.cpts_clock_shift))
+		if (cpts_register(cpsw->cpts))
 			dev_err(priv->dev, "error registering cpts device\n");
 
 	}
@@ -2796,6 +2794,7 @@ static int cpsw_probe(struct platform_device *pdev)
 	struct cpdma_params		dma_params;
 	struct cpsw_ale_params		ale_params;
 	void __iomem			*ss_regs;
+	void __iomem			*cpts_regs;
 	struct resource			*res, *ss_res;
 	const struct of_device_id	*of_id;
 	struct gpio_descs		*mode;
@@ -2823,12 +2822,6 @@ static int cpsw_probe(struct platform_device *pdev)
 	priv->dev  = &ndev->dev;
 	priv->msg_enable = netif_msg_init(debug_level, CPSW_DEBUG);
 	cpsw->rx_packet_max = max(rx_packet_max, 128);
-	cpsw->cpts = devm_kzalloc(&pdev->dev, sizeof(struct cpts), GFP_KERNEL);
-	if (!cpsw->cpts) {
-		dev_err(&pdev->dev, "error allocating cpts\n");
-		ret = -ENOMEM;
-		goto clean_ndev_ret;
-	}
 
 	mode = devm_gpiod_get_array_optional(&pdev->dev, "mode", GPIOD_OUT_LOW);
 	if (IS_ERR(mode)) {
@@ -2916,7 +2909,7 @@ static int cpsw_probe(struct platform_device *pdev)
 	switch (cpsw->version) {
 	case CPSW_VERSION_1:
 		cpsw->host_port_regs = ss_regs + CPSW1_HOST_PORT_OFFSET;
-		cpsw->cpts->reg      = ss_regs + CPSW1_CPTS_OFFSET;
+		cpts_regs		= ss_regs + CPSW1_CPTS_OFFSET;
 		cpsw->hw_stats	     = ss_regs + CPSW1_HW_STATS;
 		dma_params.dmaregs   = ss_regs + CPSW1_CPDMA_OFFSET;
 		dma_params.txhdp     = ss_regs + CPSW1_STATERAM_OFFSET;
@@ -2930,7 +2923,7 @@ static int cpsw_probe(struct platform_device *pdev)
 	case CPSW_VERSION_3:
 	case CPSW_VERSION_4:
 		cpsw->host_port_regs = ss_regs + CPSW2_HOST_PORT_OFFSET;
-		cpsw->cpts->reg      = ss_regs + CPSW2_CPTS_OFFSET;
+		cpts_regs		= ss_regs + CPSW2_CPTS_OFFSET;
 		cpsw->hw_stats	     = ss_regs + CPSW2_HW_STATS;
 		dma_params.dmaregs   = ss_regs + CPSW2_CPDMA_OFFSET;
 		dma_params.txhdp     = ss_regs + CPSW2_STATERAM_OFFSET;
@@ -2997,6 +2990,14 @@ static int cpsw_probe(struct platform_device *pdev)
 		goto clean_dma_ret;
 	}
 
+	cpsw->cpts = cpts_create(cpsw->dev, cpts_regs,
+				 cpsw->data.cpts_clock_mult,
+				 cpsw->data.cpts_clock_shift);
+	if (IS_ERR(cpsw->cpts)) {
+		ret = PTR_ERR(cpsw->cpts);
+		goto clean_ale_ret;
+	}
+
 	ndev->irq = platform_get_irq(pdev, 1);
 	if (ndev->irq < 0) {
 		dev_err(priv->dev, "error getting irq resource\n");
@@ -3112,6 +3113,7 @@ static int cpsw_remove(struct platform_device *pdev)
 		unregister_netdev(cpsw->slaves[1].ndev);
 	unregister_netdev(ndev);
 
+	cpts_release(cpsw->cpts);
 	cpsw_ale_destroy(cpsw->ale);
 	cpdma_ctlr_destroy(cpsw->dma);
 	cpsw_remove_dt(pdev);
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index fe1bb7f..9356803 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -248,24 +248,6 @@ static void cpts_overflow_check(struct work_struct *work)
 	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
 }
 
-static void cpts_clk_init(struct device *dev, struct cpts *cpts)
-{
-	if (!cpts->refclk) {
-		cpts->refclk = devm_clk_get(dev, "cpts");
-		if (IS_ERR(cpts->refclk)) {
-			dev_err(dev, "Failed to get cpts refclk\n");
-			cpts->refclk = NULL;
-			return;
-		}
-	}
-	clk_prepare_enable(cpts->refclk);
-}
-
-static void cpts_clk_release(struct cpts *cpts)
-{
-	clk_disable_unprepare(cpts->refclk);
-}
-
 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
 		      u16 ts_seqid, u8 ts_msgtype)
 {
@@ -372,34 +354,27 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 }
 EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
 
-int cpts_register(struct device *dev, struct cpts *cpts,
-		  u32 mult, u32 shift)
+int cpts_register(struct cpts *cpts)
 {
 	int err, i;
 
-	cpts->info = cpts_info;
-	spin_lock_init(&cpts->lock);
-
-	cpts->cc.read = cpts_systim_read;
-	cpts->cc.mask = CLOCKSOURCE_MASK(32);
-	cpts->cc_mult = mult;
-	cpts->cc.mult = mult;
-	cpts->cc.shift = shift;
-
 	INIT_LIST_HEAD(&cpts->events);
 	INIT_LIST_HEAD(&cpts->pool);
 	for (i = 0; i < CPTS_MAX_EVENTS; i++)
 		list_add(&cpts->pool_data[i].list, &cpts->pool);
 
-	cpts_clk_init(dev, cpts);
+	clk_enable(cpts->refclk);
+
 	cpts_write32(cpts, CPTS_EN, control);
 	cpts_write32(cpts, TS_PEND_EN, int_enable);
 
+	/* reinitialize cc.mult to original value as it can be modified
+	 * by cpts_ptp_adjfreq().
+	 */
+	cpts->cc.mult = cpts->cc_mult;
 	timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
 
-	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
-
-	cpts->clock = ptp_clock_register(&cpts->info, dev);
+	cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
 	if (IS_ERR(cpts->clock)) {
 		err = PTR_ERR(cpts->clock);
 		cpts->clock = NULL;
@@ -412,27 +387,72 @@ int cpts_register(struct device *dev, struct cpts *cpts,
 	return 0;
 
 err_ptp:
-	if (cpts->refclk)
-		cpts_clk_release(cpts);
+	clk_disable(cpts->refclk);
 	return err;
 }
 EXPORT_SYMBOL_GPL(cpts_register);
 
 void cpts_unregister(struct cpts *cpts)
 {
-	if (cpts->clock) {
-		ptp_clock_unregister(cpts->clock);
-		cancel_delayed_work_sync(&cpts->overflow_work);
-	}
+	if (WARN_ON(!cpts->clock))
+		return;
+
+	cancel_delayed_work_sync(&cpts->overflow_work);
+
+	ptp_clock_unregister(cpts->clock);
+	cpts->clock = NULL;
 
 	cpts_write32(cpts, 0, int_enable);
 	cpts_write32(cpts, 0, control);
 
-	if (cpts->refclk)
-		cpts_clk_release(cpts);
+	clk_disable(cpts->refclk);
 }
 EXPORT_SYMBOL_GPL(cpts_unregister);
 
+struct cpts *cpts_create(struct device *dev, void __iomem *regs,
+			 u32 mult, u32 shift)
+{
+	struct cpts *cpts;
+
+	cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
+	if (!cpts)
+		return ERR_PTR(-ENOMEM);
+
+	cpts->dev = dev;
+	cpts->reg = (struct cpsw_cpts __iomem *)regs;
+	spin_lock_init(&cpts->lock);
+	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
+
+	cpts->refclk = devm_clk_get(dev, "cpts");
+	if (IS_ERR(cpts->refclk)) {
+		dev_err(dev, "Failed to get cpts refclk\n");
+		return ERR_PTR(PTR_ERR(cpts->refclk));
+	}
+
+	clk_prepare(cpts->refclk);
+
+	cpts->cc.read = cpts_systim_read;
+	cpts->cc.mask = CLOCKSOURCE_MASK(32);
+	cpts->cc.shift = shift;
+	cpts->cc_mult = mult;
+	cpts->info = cpts_info;
+
+	return cpts;
+}
+EXPORT_SYMBOL_GPL(cpts_create);
+
+void cpts_release(struct cpts *cpts)
+{
+	if (!cpts)
+		return;
+
+	if (WARN_ON(!cpts->clock))
+		return;
+
+	clk_unprepare(cpts->refclk);
+}
+EXPORT_SYMBOL_GPL(cpts_release);
+
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("TI CPTS driver");
 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index 29a1e80c..e7d857c 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -20,6 +20,8 @@
 #ifndef _TI_CPTS_H_
 #define _TI_CPTS_H_
 
+#if IS_ENABLED(CONFIG_TI_CPTS)
+
 #include <linux/clk.h>
 #include <linux/clkdev.h>
 #include <linux/clocksource.h>
@@ -108,10 +110,10 @@ struct cpts_event {
 };
 
 struct cpts {
+	struct device *dev;
 	struct cpsw_cpts __iomem *reg;
 	int tx_enable;
 	int rx_enable;
-#if IS_ENABLED(CONFIG_TI_CPTS)
 	struct ptp_clock_info info;
 	struct ptp_clock *clock;
 	spinlock_t lock; /* protects time registers */
@@ -124,14 +126,15 @@ struct cpts {
 	struct list_head events;
 	struct list_head pool;
 	struct cpts_event pool_data[CPTS_MAX_EVENTS];
-#endif
 };
 
-#if IS_ENABLED(CONFIG_TI_CPTS)
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb);
-int cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift);
+int cpts_register(struct cpts *cpts);
 void cpts_unregister(struct cpts *cpts);
+struct cpts *cpts_create(struct device *dev, void __iomem *regs,
+			 u32 mult, u32 shift);
+void cpts_release(struct cpts *cpts);
 
 static inline void cpts_rx_enable(struct cpts *cpts, int enable)
 {
@@ -154,6 +157,8 @@ static inline bool cpts_is_tx_enabled(struct cpts *cpts)
 }
 
 #else
+struct cpts;
+
 static inline void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 }
@@ -161,8 +166,19 @@ static inline void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 }
 
+static inline
+struct cpts *cpts_create(struct device *dev, void __iomem *regs,
+			 u32 mult, u32 shift)
+{
+	return NULL;
+}
+
+static inline void cpts_release(struct cpts *cpts)
+{
+}
+
 static inline int
-cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift)
+cpts_register(struct cpts *cpts)
 {
 	return 0;
 }
-- 
2.10.1

[PATCH v4 10/13] net: ethernet: ti: cpts: move dt props parsing to cpts driver

[Grygorii Strashko]

Move DT properties parsing into CPTS driver to simplify CPSW
code and CPTS driver porting on other SoC in the future
(like Keystone 2) - with this change it will not be required
to add the same DT parsing code in Keystone 2 NETCP driver.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/net/ethernet/ti/cpsw.c | 16 +---------------
 drivers/net/ethernet/ti/cpsw.h |  2 --
 drivers/net/ethernet/ti/cpts.c | 32 +++++++++++++++++++++++++++++---
 drivers/net/ethernet/ti/cpts.h |  5 +++--
 4 files changed, 33 insertions(+), 22 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index deb008a..259c717 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -2524,18 +2524,6 @@ static int cpsw_probe_dt(struct cpsw_platform_data *data,
 	}
 	data->active_slave = prop;
 
-	if (of_property_read_u32(node, "cpts_clock_mult", &prop)) {
-		dev_err(&pdev->dev, "Missing cpts_clock_mult property in the DT.\n");
-		return -EINVAL;
-	}
-	data->cpts_clock_mult = prop;
-
-	if (of_property_read_u32(node, "cpts_clock_shift", &prop)) {
-		dev_err(&pdev->dev, "Missing cpts_clock_shift property in the DT.\n");
-		return -EINVAL;
-	}
-	data->cpts_clock_shift = prop;
-
 	data->slave_data = devm_kzalloc(&pdev->dev, data->slaves
 					* sizeof(struct cpsw_slave_data),
 					GFP_KERNEL);
@@ -2990,9 +2978,7 @@ static int cpsw_probe(struct platform_device *pdev)
 		goto clean_dma_ret;
 	}
 
-	cpsw->cpts = cpts_create(cpsw->dev, cpts_regs,
-				 cpsw->data.cpts_clock_mult,
-				 cpsw->data.cpts_clock_shift);
+	cpsw->cpts = cpts_create(cpsw->dev, cpts_regs, cpsw->dev->of_node);
 	if (IS_ERR(cpsw->cpts)) {
 		ret = PTR_ERR(cpsw->cpts);
 		goto clean_ale_ret;
diff --git a/drivers/net/ethernet/ti/cpsw.h b/drivers/net/ethernet/ti/cpsw.h
index 16b54c6..6c3037a 100644
--- a/drivers/net/ethernet/ti/cpsw.h
+++ b/drivers/net/ethernet/ti/cpsw.h
@@ -31,8 +31,6 @@ struct cpsw_platform_data {
 	u32	channels;	/* number of cpdma channels (symmetric) */
 	u32	slaves;		/* number of slave cpgmac ports */
 	u32	active_slave; /* time stamping, ethtool and SIOCGMIIPHY slave */
-	u32	cpts_clock_mult;  /* convert input clock ticks to nanoseconds */
-	u32	cpts_clock_shift; /* convert input clock ticks to nanoseconds */
 	u32	ale_entries;	/* ale table size */
 	u32	bd_ram_size;  /*buffer descriptor ram size */
 	u32	mac_control;	/* Mac control register */
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 9356803..59c09a4 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -409,10 +409,34 @@ void cpts_unregister(struct cpts *cpts)
 }
 EXPORT_SYMBOL_GPL(cpts_unregister);
 
+static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
+{
+	int ret = -EINVAL;
+	u32 prop;
+
+	if (of_property_read_u32(node, "cpts_clock_mult", &prop))
+		goto  of_error;
+	/* save cc.mult original value as it can be modified
+	 * by cpts_ptp_adjfreq().
+	 */
+	cpts->cc_mult = prop;
+
+	if (of_property_read_u32(node, "cpts_clock_shift", &prop))
+		goto  of_error;
+	cpts->cc.shift = prop;
+
+	return 0;
+
+of_error:
+	dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
+	return ret;
+}
+
 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
-			 u32 mult, u32 shift)
+			 struct device_node *node)
 {
 	struct cpts *cpts;
+	int ret;
 
 	cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
 	if (!cpts)
@@ -423,6 +447,10 @@ struct cpts *cpts_create(struct device *dev, void __iomem *regs,
 	spin_lock_init(&cpts->lock);
 	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
 
+	ret = cpts_of_parse(cpts, node);
+	if (ret)
+		return ERR_PTR(ret);
+
 	cpts->refclk = devm_clk_get(dev, "cpts");
 	if (IS_ERR(cpts->refclk)) {
 		dev_err(dev, "Failed to get cpts refclk\n");
@@ -433,8 +461,6 @@ struct cpts *cpts_create(struct device *dev, void __iomem *regs,
 
 	cpts->cc.read = cpts_systim_read;
 	cpts->cc.mask = CLOCKSOURCE_MASK(32);
-	cpts->cc.shift = shift;
-	cpts->cc_mult = mult;
 	cpts->info = cpts_info;
 
 	return cpts;
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index e7d857c..5da23af 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -27,6 +27,7 @@
 #include <linux/clocksource.h>
 #include <linux/device.h>
 #include <linux/list.h>
+#include <linux/of.h>
 #include <linux/ptp_clock_kernel.h>
 #include <linux/skbuff.h>
 #include <linux/timecounter.h>
@@ -133,7 +134,7 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 int cpts_register(struct cpts *cpts);
 void cpts_unregister(struct cpts *cpts);
 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
-			 u32 mult, u32 shift);
+			 struct device_node *node);
 void cpts_release(struct cpts *cpts);
 
 static inline void cpts_rx_enable(struct cpts *cpts, int enable)
@@ -168,7 +169,7 @@ static inline void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 
 static inline
 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
-			 u32 mult, u32 shift)
+			 struct device_node *node)
 {
 	return NULL;
 }
-- 
2.10.1

[PATCH v4 11/13] clocksource: export the clocks_calc_mult_shift to use by timestamp code

[Grygorii Strashko]

From: Murali Karicheri <m-karicheri2@ti.com>

The CPSW CPTS driver is capable of doing timestamping on tx/rx packets and
requires to know mult and shift factors for timestamp conversion from raw
value to nanoseconds (ptp clock). Now these mult and shift factors are
calculated manually and provided through DT, which makes very hard to
support of a lot number of platforms, especially if CPTS refclk is not the
same for some kind of boards and depends on efuse settings (Keystone 2
platforms). Hence, export clocks_calc_mult_shift() to allow drivers like
CPSW CPTS (and other ptp drivesr) to benefit from automaitc calculation of
mult and shift factors.

Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
---
 kernel/time/clocksource.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 7e4fad7..150242c 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -89,6 +89,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec)
 	*mult = tmp;
 	*shift = sft;
 }
+EXPORT_SYMBOL_GPL(clocks_calc_mult_shift);
 
 /*[Clocksource internal variables]---------
  * curr_clocksource:
-- 
2.10.1

[PATCH v4 12/13] net: ethernet: ti: cpts: calc mult and shift from refclk freq

[Grygorii Strashko]

The cyclecounter mult and shift values can be calculated based on the
CPTS rfclk frequency and timekeepnig framework provides required algos
and API's.

Hence, calc mult and shift basing on CPTS rfclk frequency if both
cpts_clock_shift and cpts_clock_mult properties are not provided in DT (the
basis of calculation algorithm is borrowed from
__clocksource_update_freq_scale() commit 7d2f944a2b83 ("clocksource:
Provide a generic mult/shift factor calculation")). After this change
cpts_clock_shift and cpts_clock_mult DT properties will become optional.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 Documentation/devicetree/bindings/net/cpsw.txt |  8 ++--
 drivers/net/ethernet/ti/cpts.c                 | 53 +++++++++++++++++++++++---
 2 files changed, 52 insertions(+), 9 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/cpsw.txt b/Documentation/devicetree/bindings/net/cpsw.txt
index 5ad439f..ebda7c9 100644
--- a/Documentation/devicetree/bindings/net/cpsw.txt
+++ b/Documentation/devicetree/bindings/net/cpsw.txt
@@ -20,8 +20,6 @@ Required properties:
 - slaves		: Specifies number for slaves
 - active_slave		: Specifies the slave to use for time stamping,
 			  ethtool and SIOCGMIIPHY
-- cpts_clock_mult	: Numerator to convert input clock ticks into nanoseconds
-- cpts_clock_shift	: Denominator to convert input clock ticks into nanoseconds
 
 Optional properties:
 - ti,hwmods		: Must be "cpgmac0"
@@ -35,7 +33,11 @@ Optional properties:
 			  For example in dra72x-evm, pcf gpio has to be
 			  driven low so that cpsw slave 0 and phy data
 			  lines are connected via mux.
-
+- cpts_clock_mult	: Numerator to convert input clock ticks into nanoseconds
+- cpts_clock_shift	: Denominator to convert input clock ticks into nanoseconds
+			  Mult and shift will be calculated basing on CPTS
+			  rftclk frequency if both cpts_clock_shift and
+			  cpts_clock_mult properties are not provided.
 
 Slave Properties:
 Required properties:
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 59c09a4..361d13a 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -409,21 +409,60 @@ void cpts_unregister(struct cpts *cpts)
 }
 EXPORT_SYMBOL_GPL(cpts_unregister);
 
+static void cpts_calc_mult_shift(struct cpts *cpts)
+{
+	u64 frac, maxsec, ns;
+	u32 freq, mult, shift;
+
+	freq = clk_get_rate(cpts->refclk);
+
+	/* Calc the maximum number of seconds which we can run before
+	 * wrapping around.
+	 */
+	maxsec = cpts->cc.mask;
+	do_div(maxsec, freq);
+	/* limit conversation rate to 10 sec as higher values will produce
+	 * too small mult factors and so reduce the conversion accuracy
+	 */
+	if (maxsec > 10)
+		maxsec = 10;
+
+	if (cpts->cc_mult || cpts->cc.shift)
+		return;
+
+	clocks_calc_mult_shift(&mult, &shift, freq, NSEC_PER_SEC, maxsec);
+
+	cpts->cc_mult = mult;
+	cpts->cc.mult = mult;
+	cpts->cc.shift = shift;
+
+	frac = 0;
+	ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
+
+	dev_info(cpts->dev,
+		 "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
+		 freq, cpts->cc_mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
+}
+
 static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
 {
 	int ret = -EINVAL;
 	u32 prop;
 
-	if (of_property_read_u32(node, "cpts_clock_mult", &prop))
-		goto  of_error;
 	/* save cc.mult original value as it can be modified
 	 * by cpts_ptp_adjfreq().
 	 */
-	cpts->cc_mult = prop;
+	cpts->cc_mult = 0;
+	if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
+		cpts->cc_mult = prop;
+
+	cpts->cc.shift = 0;
+	if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
+		cpts->cc.shift = prop;
 
-	if (of_property_read_u32(node, "cpts_clock_shift", &prop))
-		goto  of_error;
-	cpts->cc.shift = prop;
+	if ((cpts->cc_mult && !cpts->cc.shift) ||
+	    (!cpts->cc_mult && cpts->cc.shift))
+		goto of_error;
 
 	return 0;
 
@@ -463,6 +502,8 @@ struct cpts *cpts_create(struct device *dev, void __iomem *regs,
 	cpts->cc.mask = CLOCKSOURCE_MASK(32);
 	cpts->info = cpts_info;
 
+	cpts_calc_mult_shift(cpts);
+
 	return cpts;
 }
 EXPORT_SYMBOL_GPL(cpts_create);
-- 
2.10.1

[PATCH v4 13/13] net: ethernet: ti: cpts: fix overflow check period

[Grygorii Strashko]

The CPTS drivers uses 8sec period for overflow checking with
assumption that CPTS retclk will not exceed 500MHz. But that's not
true on some TI platforms (Kesytone 2). As result, it is possible that
CPTS counter will overflow more than once between two readings.

Hence, fix it by selecting overflow check period dynamically as
max_sec_before_overflow/2, where
 max_sec_before_overflow = max_counter_val / rftclk_freq.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
---
 drivers/net/ethernet/ti/cpts.c | 10 +++++++---
 drivers/net/ethernet/ti/cpts.h |  4 +---
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 361d13a..a60d837 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -245,7 +245,7 @@ static void cpts_overflow_check(struct work_struct *work)
 
 	cpts_ptp_gettime(&cpts->info, &ts);
 	pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
-	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
+	schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
 }
 
 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
@@ -382,8 +382,7 @@ int cpts_register(struct cpts *cpts)
 	}
 	cpts->phc_index = ptp_clock_index(cpts->clock);
 
-	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
-
+	schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
 	return 0;
 
 err_ptp:
@@ -427,6 +426,11 @@ static void cpts_calc_mult_shift(struct cpts *cpts)
 	if (maxsec > 10)
 		maxsec = 10;
 
+	/* Calc overflow check period (maxsec / 2) */
+	cpts->ov_check_period = (HZ * maxsec) / 2;
+	dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
+		 cpts->ov_check_period);
+
 	if (cpts->cc_mult || cpts->cc.shift)
 		return;
 
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index 5da23af..c96eca2 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -97,9 +97,6 @@ enum {
 	CPTS_EV_TX,   /* Ethernet Transmit Event */
 };
 
-/* This covers any input clock up to about 500 MHz. */
-#define CPTS_OVERFLOW_PERIOD (HZ * 8)
-
 #define CPTS_FIFO_DEPTH 16
 #define CPTS_MAX_EVENTS 32
 
@@ -127,6 +124,7 @@ struct cpts {
 	struct list_head events;
 	struct list_head pool;
 	struct cpts_event pool_data[CPTS_MAX_EVENTS];
+	unsigned long ov_check_period;
 };
 
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
-- 
2.10.1

Re: [PATCH v4 09/13] net: ethernet: ti: cpts: rework initialization/deinitialization

[Richard Cochran]

On Mon, Dec 05, 2016 at 02:05:21PM -0600, Grygorii Strashko wrote:
> @@ -372,34 +354,27 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
>  }
>  EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
>  
> -int cpts_register(struct device *dev, struct cpts *cpts,
> -		  u32 mult, u32 shift)
> +int cpts_register(struct cpts *cpts)
>  {
>  	int err, i;
>  
> -	cpts->info = cpts_info;
> -	spin_lock_init(&cpts->lock);
> -
> -	cpts->cc.read = cpts_systim_read;
> -	cpts->cc.mask = CLOCKSOURCE_MASK(32);
> -	cpts->cc_mult = mult;
> -	cpts->cc.mult = mult;
> -	cpts->cc.shift = shift;
> -
>  	INIT_LIST_HEAD(&cpts->events);
>  	INIT_LIST_HEAD(&cpts->pool);
>  	for (i = 0; i < CPTS_MAX_EVENTS; i++)
>  		list_add(&cpts->pool_data[i].list, &cpts->pool);
>  
> -	cpts_clk_init(dev, cpts);
> +	clk_enable(cpts->refclk);
> +
>  	cpts_write32(cpts, CPTS_EN, control);
>  	cpts_write32(cpts, TS_PEND_EN, int_enable);
>  
> +	/* reinitialize cc.mult to original value as it can be modified
> +	 * by cpts_ptp_adjfreq().
> +	 */
> +	cpts->cc.mult = cpts->cc_mult;

This still isn't quite right.  First of all, you shouldn't clobber the
learned cc.mult value in cpts_register().  Presumably, if PTP had been
run on this port before, then the learned frequency is approximately
correct, and it should be left alone.

[ BTW, resetting the timecounter here makes no sense either.  Why
  reset the clock just because the interface goes down?  ]

Secondly, you have made the initialization order of these fields hard
to follow.  With the whole series applied:

probe()
	cpts_create()
		cpts_of_parse()
		{
			/* Set cc_mult but not cc.mult! */
			set cc_mult
			set cc.shift
		}
		cpts_calc_mult_shift()
		{
			/* Set them both. */
			cpts->cc_mult = mult;
			cpts->cc.mult = mult;
			cpts->cc.shift = shift;
		}
/* later on */
cpts_register()
	cpts->cc.mult = cpts->cc_mult;

There is no need for such complexity.  Simply set cc.mult in
cpts_create() _once_, immediately after the call to
cpts_calc_mult_shift().

You can remove the assignment from cpts_calc_mult_shift() and
cpts_register().

Thanks,
Richard

Re: [PATCH v4 09/13] net: ethernet: ti: cpts: rework initialization/deinitialization

[Grygorii Strashko]

On 12/06/2016 07:40 AM, Richard Cochran wrote:
> On Mon, Dec 05, 2016 at 02:05:21PM -0600, Grygorii Strashko wrote:
>> @@ -372,34 +354,27 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
>>  }
>>  EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
>>  
>> -int cpts_register(struct device *dev, struct cpts *cpts,
>> -		  u32 mult, u32 shift)
>> +int cpts_register(struct cpts *cpts)
>>  {
>>  	int err, i;
>>  
>> -	cpts->info = cpts_info;
>> -	spin_lock_init(&cpts->lock);
>> -
>> -	cpts->cc.read = cpts_systim_read;
>> -	cpts->cc.mask = CLOCKSOURCE_MASK(32);
>> -	cpts->cc_mult = mult;
>> -	cpts->cc.mult = mult;
>> -	cpts->cc.shift = shift;
>> -
>>  	INIT_LIST_HEAD(&cpts->events);
>>  	INIT_LIST_HEAD(&cpts->pool);
>>  	for (i = 0; i < CPTS_MAX_EVENTS; i++)
>>  		list_add(&cpts->pool_data[i].list, &cpts->pool);
>>  
>> -	cpts_clk_init(dev, cpts);
>> +	clk_enable(cpts->refclk);
>> +
>>  	cpts_write32(cpts, CPTS_EN, control);
>>  	cpts_write32(cpts, TS_PEND_EN, int_enable);
>>  
>> +	/* reinitialize cc.mult to original value as it can be modified
>> +	 * by cpts_ptp_adjfreq().
>> +	 */
>> +	cpts->cc.mult = cpts->cc_mult;
> 
> This still isn't quite right.  First of all, you shouldn't clobber the
> learned cc.mult value in cpts_register().  Presumably, if PTP had been
> run on this port before, then the learned frequency is approximately
> correct, and it should be left alone.
> 
> [ BTW, resetting the timecounter here makes no sense either.  Why
>   reset the clock just because the interface goes down?  ]
> 

Huh. This is how it works now (even before my changes) - this is just refactoring!
(really new thing is the only cpts_calc_mult_shift()).

Also, this is how cpts is supported now as part of cpsw (and keystone):
configure cpsw (cpts)
- ifup
   cpsw (*soft_reset*, full reconfiguration of cpsw)
  (start cpts) - cpts/ptp active

- ifdown
   if last netdev - shutdown/poweroff cpsw (cpts)

in other words, cpts/ptp is expected to work once and until at least one cpsw netdev is active.

Also there are additional questions such as:
- is there guarantee that cpsw port will be connected to the same network after ifup?
- should there be possibility to reset cc.mult if it's value will be kept from the previous run?

> Secondly, you have made the initialization order of these fields hard
> to follow.  With the whole series applied:
> 
> probe()
> 	cpts_create()
> 		cpts_of_parse()
> 		{
> 			/* Set cc_mult but not cc.mult! */
> 			set cc_mult
> 			set cc.shift
> 		}
> 		cpts_calc_mult_shift()
> 		{
> 			/* Set them both. */
> 			cpts->cc_mult = mult;
> 			cpts->cc.mult = mult; 

^^ this assignment of cpts->cc.mult not required.

> 			cpts->cc.shift = shift;
			

only in case there were not set in DT before
(I have a requirement to support both - DT and cpts_calc_mult_shift and
 that introduces a bit of complexity)

Also, I've tried not to add more fields in struct cpts.

> 		}
> /* later on */
> cpts_register()
> 	cpts->cc.mult = cpts->cc_mult;
> 
> There is no need for such complexity.  Simply set cc.mult in
> cpts_create() _once_, immediately after the call to
> cpts_calc_mult_shift().
> 
> You can remove the assignment from cpts_calc_mult_shift() and
> cpts_register().

Just to clarify: do you propose to get rid of cpts->cc_mult at all?

static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
{
...
	if (ppb < 0) {
		neg_adj = 1;
		ppb = -ppb;
	}
	mult = cpts->cc_mult;
		^^^^^^^^^^^^^^
	adj = mult;
	adj *= ppb;
	diff = div_u64(adj, 1000000000ULL);
...
	cpts->cc.mult = neg_adj ? mult - diff : mult + diff;

Honestly, i'd not prefer to change functional behavior of ptp clock as part of
this series.

-- 
regards,
-grygorii

Re: [PATCH v4 09/13] net: ethernet: ti: cpts: rework initialization/deinitialization

[Richard Cochran]

On Tue, Dec 06, 2016 at 10:45:55AM -0600, Grygorii Strashko wrote:
> On 12/06/2016 07:40 AM, Richard Cochran wrote:
> > [ BTW, resetting the timecounter here makes no sense either.  Why
> >   reset the clock just because the interface goes down?  ]
> > 
> 
> Huh. This is how it works now (even before my changes) - this is just refactoring!
> (really new thing is the only cpts_calc_mult_shift()).

The cpts_register() used to be called from probe(), but this changed
without any review in f280e89ad.  That wasn't your fault, but still...
 
> Also there are additional questions such as:
> - is there guarantee that cpsw port will be connected to the same network after ifup?

The network is not relevant.  PTP time is a global standard, just like
with NTP.  We don't reset the NTP clock with ifup/down, do we?

> - should there be possibility to reset cc.mult if it's value will be kept from the previous run?

cc.mult will change naturally according to the operation of the user
space PTP stack.  There is no need to reset it that I can see.
 
> > Secondly, you have made the initialization order of these fields hard
> > to follow.  With the whole series applied:
> > 
> > probe()
> > 	cpts_create()
> > 		cpts_of_parse()
> > 		{
> > 			/* Set cc_mult but not cc.mult! */
> > 			set cc_mult
> > 			set cc.shift
> > 		}
> > 		cpts_calc_mult_shift()
> > 		{
> > 			/* Set them both. */
> > 			cpts->cc_mult = mult;
> > 			cpts->cc.mult = mult; 
> 
> ^^ this assignment of cpts->cc.mult not required.

You wrote the code, not me.
 
> > 			cpts->cc.shift = shift;
> 			
> 
> only in case there were not set in DT before
> (I have a requirement to support both - DT and cpts_calc_mult_shift and
>  that introduces a bit of complexity)
> 
> Also, I've tried not to add more fields in struct cpts.
> 
> > 		}
> > /* later on */
> > cpts_register()
> > 	cpts->cc.mult = cpts->cc_mult;
> > 
> > There is no need for such complexity.  Simply set cc.mult in
> > cpts_create() _once_, immediately after the call to
> > cpts_calc_mult_shift().
> > 
> > You can remove the assignment from cpts_calc_mult_shift() and
> > cpts_register().
> 
> Just to clarify: do you propose to get rid of cpts->cc_mult at all?

No.  Read what I said before:

   There is no need for such complexity.  Simply set cc.mult in
   cpts_create() _once_, immediately after the call to
   cpts_calc_mult_shift().

> Honestly, i'd not prefer to change functional behavior of ptp clock as part of
> this series.

Fair enough.  The bogus clock reset existed before your series.

But please don't obfuscate simple initialization routines.  The way
you set cc.mult and cc_mult is illogical and convoluted.

Thanks,
Richard

Re: [PATCH v4 09/13] net: ethernet: ti: cpts: rework initialization/deinitialization

[Grygorii Strashko]

Hi Richard,

On 12/06/2016 11:18 AM, Richard Cochran wrote:
> On Tue, Dec 06, 2016 at 10:45:55AM -0600, Grygorii Strashko wrote:
>> On 12/06/2016 07:40 AM, Richard Cochran wrote:
>>> [ BTW, resetting the timecounter here makes no sense either.  Why
>>>   reset the clock just because the interface goes down?  ]
>>>
>>
>> Huh. This is how it works now (even before my changes) - this is just refactoring!
>> (really new thing is the only cpts_calc_mult_shift()).
> 
> The cpts_register() used to be called from probe(), but this changed
> without any review in f280e89ad.  That wasn't your fault, but still...
>  
>> Also there are additional questions such as:
>> - is there guarantee that cpsw port will be connected to the same network after ifup?
> 
> The network is not relevant.  PTP time is a global standard, just like
> with NTP.  We don't reset the NTP clock with ifup/down, do we?

But we do reset whole cpsw :( and that's required to support PM use cases as
suspend/resume.

There are also PM requirement to shutdown cpsw in case all interfaces are down.

More over, there are requirement to minimize cpsw power consumption in case all links are
disconnected (and cpts is special case here).

So, at least resetting of the timecounter still required.



> 
>> - should there be possibility to reset cc.mult if it's value will be kept from the previous run?
> 
> cc.mult will change naturally according to the operation of the user
> space PTP stack.  There is no need to reset it that I can see.
>  
>>> Secondly, you have made the initialization order of these fields hard
>>> to follow.  With the whole series applied:
>>>
>>> probe()
>>> 	cpts_create()
>>> 		cpts_of_parse()
>>> 		{
>>> 			/* Set cc_mult but not cc.mult! */
>>> 			set cc_mult
>>> 			set cc.shift
>>> 		}
>>> 		cpts_calc_mult_shift()
>>> 		{
>>> 			/* Set them both. */
>>> 			cpts->cc_mult = mult;
>>> 			cpts->cc.mult = mult; 
>>
>> ^^ this assignment of cpts->cc.mult not required.
> 
> You wrote the code, not me.

Sry, I meant, thank for catching this.

>  
>>> 			cpts->cc.shift = shift;
>> 			
>>
>> only in case there were not set in DT before
>> (I have a requirement to support both - DT and cpts_calc_mult_shift and
>>  that introduces a bit of complexity)
>>
>> Also, I've tried not to add more fields in struct cpts.
>>
>>> 		}
>>> /* later on */
>>> cpts_register()
>>> 	cpts->cc.mult = cpts->cc_mult;
>>>
>>> There is no need for such complexity.  Simply set cc.mult in
>>> cpts_create() _once_, immediately after the call to
>>> cpts_calc_mult_shift().
>>>
>>> You can remove the assignment from cpts_calc_mult_shift() and
>>> cpts_register().
>>
>> Just to clarify: do you propose to get rid of cpts->cc_mult at all?
> 
> No.  Read what I said before:
> 
>    There is no need for such complexity.  Simply set cc.mult in
>    cpts_create() _once_, immediately after the call to
>    cpts_calc_mult_shift().
> 
>> Honestly, i'd not prefer to change functional behavior of ptp clock as part of
>> this series.
> 
> Fair enough.  The bogus clock reset existed before your series.
> 
> But please don't obfuscate simple initialization routines.  The way
> you set cc.mult and cc_mult is illogical and convoluted.
> 

Ok. I'll try to optimize it following your directions.

Thanks.

-- 
regards,
-grygorii

Re: [PATCH v4 09/13] net: ethernet: ti: cpts: rework initialization/deinitialization

[Richard Cochran]

On Tue, Dec 06, 2016 at 11:49:14AM -0600, Grygorii Strashko wrote:
> But we do reset whole cpsw :( and that's required to support PM use cases as
> suspend/resume.

The code is resetting the clock unconditionally on ifup/down.  That
sucks.  If you reset the clock *only* after resume, that would be ok.
 
> There are also PM requirement to shutdown cpsw in case all interfaces are down.

Well, those requirements are not too smart.  As an end user, I expect
that ifdown/up does not change the time.  There isn't any reason to
reset the clock in this case.

> More over, there are requirement to minimize cpsw power consumption in case all links are
> disconnected (and cpts is special case here).
> 
> So, at least resetting of the timecounter still required.

Only if you follow that poorly conceived PM plan.  Anyhow, I agree
that it isn't the task of your present series to fix that.

> Ok. I'll try to optimize it following your directions.

What I would like to see is: initialize the cyclecounter fields
exactly once.

Thanks,
Richard