[PATCH net-next v3 0/5] Adding PHY-Tunables and downshift support

[PATCH net-next v3 0/5] Adding PHY-Tunables and downshift support

[Allan W. Nielsen]

Hi All,

This follow fixes the comments provided on the v2 series.

Following is the list of changes.
- Spelling in "net: phy: Add downshift get/set support in Microsemi PHYs driver"

Ethtool patches will follow shortly.

Old cover letters included below.

Please review.

Best regards
Allan and Raju


Raju Lakkaraju (5):
  ethtool: (uapi) Add ETHTOOL_PHY_GTUNABLE and ETHTOOL_PHY_STUNABLE
  ethtool: Implements ETHTOOL_PHY_GTUNABLE/ETHTOOL_PHY_STUNABLE
  ethtool: (uapi) Add ETHTOOL_PHY_DOWNSHIFT to PHY tunables
  ethtool: Core impl for ETHTOOL_PHY_DOWNSHIFT tunable
  net: phy: Add downshift get/set support in Microsemi PHYs driver

 drivers/net/phy/mscc.c       | 100 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/phy.h          |   7 +++
 include/uapi/linux/ethtool.h |  18 +++++++-
 net/core/ethtool.c           |  93 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 217 insertions(+), 1 deletion(-)

> From 5ca4dac36f45e097b93ae4cfdf35a8922e5d975e Mon Sep 17 00:00:00 2001
> prom: "Allan W. Nielsen" <allan.nielsen@microsemi.com>
> Date: Mon, 14 Nov 2016 10:04:07 +0100
> Subject: [PATCH net-next v2 0/5] Adding PHY-Tunables and downshift support
> 
> Hi,
> 
> This is a follow-up on the patch series posted at Fri, 4 Nov 2016 10:55:25
> +0100 (old cover letter included below).
> 
> The following is changed/added/addressed:
> - Support for __ethtool_get_strings()/phy_tunables is added
> - Using DOWNSHIFT_DEV_DISABLE define instead of '0' when disabling
> - If downshifting clould not be eanbled with the requested count, then a
>   trace message with a hist is printed.
> - Using ERANGE as requested by Andrew.
> - Andrew suggested to use ENOSUPP when a tunable is not implemented We kept
>   the EINVAL because ENOSUPP does not exists, and the existing MAC-level
>   tunable is also using EINVAL in the same scenario.
> - Andrew suggested that the driver should accept a count of 1 and "just"
>   round it up to 2 (the nearest allowed value). We discussed it a bit (Raju
>   and I) and preferred to return EINVAL when a configuration value could
>   not be accommodated. People which wants "help" to choose a supported
>   value should be using the DOWNSHIFT_DEV_DEFAULT_COUNT value.
> - (ethtool) Syntax is changed from "--set-phy-tunable downshift on|off|%d"
>   to "--set-phy-tunable [downshift on|off [count N]]" - as requested by
>   Andrew.
> 
> Ethtool patches will follow shortly.
>
> Old cover letter:
> > From 1a318266822f5d74c58b5219ebbdf5a6a5f567dc Mon Sep 17 00:00:00 2001
> > From: "Allan W. Nielsen" <allan.nielsen@microsemi.com>
> > Date: Fri, 4 Nov 2016 10:55:25 +0100
> > Subject: [PATCH net-next 0/5] Adding PHY-Tunables and downshift support
> > 
> > Hi All,
> > 
> > This series add support for PHY tunables, and uses this facility to configure
> > downshifting. The downshifting mechanism is implemented for MSCC phys.
> > 
> > This series tries to address the comments provided back in mid October when this
> > feature was posted along with fast-link-failure. Fast-link-failure has been
> > separated out, but we would like to pick continue on that if/when we agree on
> > how the phy-tunables and downshifting should be done.
> > 
> > The proposed generic interface is similar to ETHTOOL_GTUNABLE/ETHTOOL_STUNABLE,
> > it uses the same type (ethtool_tunable/tunable_type_id) but a new enum
> > (phy_tunable_id) is added to reflect the PHY tunable.
> > 
> > The implementation just call the newly added function pointers in
> > get_tunable/set_tunable phy_device structure.
> > 
> > To configure downshifting, the ethtool_tunable structure is used. 'id' must be
> > set to 'ETHTOOL_PHY_DOWNSHIFT', 'type_id' must be set to 'ETHTOOL_TUNABLE_U8'
> > and 'data' value configure the amount of downshift re-tries.
> > 
> > If configured to DOWNSHIFT_DEV_DISABLE, then downshift is disabled
> > If configured to DOWNSHIFT_DEV_DEFAULT_COUNT, then it is up to the device to
> > choose a device-specific re-try count.
> > 
> > Patches to implement this in ethtool will follow in a few minutes.

-- 
2.7.3

[PATCH net-next v3 1/5] ethtool: (uapi) Add ETHTOOL_PHY_GTUNABLE and ETHTOOL_PHY_STUNABLE

[Allan W. Nielsen]

From: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>

Defines a generic API to get/set phy tunables. The API is using the
existing ethtool_tunable/tunable_type_id types which is already being used
for mac level tunables.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Allan W. Nielsen <allan.nielsen@microsemi.com>
---
 include/uapi/linux/ethtool.h | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 8e54723..42f696f 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -248,6 +248,16 @@ struct ethtool_tunable {
 	void	*data[0];
 };
 
+enum phy_tunable_id {
+	ETHTOOL_PHY_ID_UNSPEC,
+
+	/*
+	 * Add your fresh new phy tunable attribute above and remember to update
+	 * phy_tunable_strings[] in net/core/ethtool.c
+	 */
+	__ETHTOOL_PHY_TUNABLE_COUNT,
+};
+
 /**
  * struct ethtool_regs - hardware register dump
  * @cmd: Command number = %ETHTOOL_GREGS
@@ -548,6 +558,7 @@ struct ethtool_pauseparam {
  * @ETH_SS_FEATURES: Device feature names
  * @ETH_SS_RSS_HASH_FUNCS: RSS hush function names
  * @ETH_SS_PHY_STATS: Statistic names, for use with %ETHTOOL_GPHYSTATS
+ * @ETH_SS_PHY_TUNABLES: PHY tunable names
  */
 enum ethtool_stringset {
 	ETH_SS_TEST		= 0,
@@ -558,6 +569,7 @@ enum ethtool_stringset {
 	ETH_SS_RSS_HASH_FUNCS,
 	ETH_SS_TUNABLES,
 	ETH_SS_PHY_STATS,
+	ETH_SS_PHY_TUNABLES,
 };
 
 /**
@@ -1313,7 +1325,8 @@ struct ethtool_per_queue_op {
 
 #define ETHTOOL_GLINKSETTINGS	0x0000004c /* Get ethtool_link_settings */
 #define ETHTOOL_SLINKSETTINGS	0x0000004d /* Set ethtool_link_settings */
-
+#define ETHTOOL_PHY_GTUNABLE	0x0000004e /* Get PHY tunable configuration */
+#define ETHTOOL_PHY_STUNABLE	0x0000004f /* Set PHY tunable configuration */
 
 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET
-- 
2.7.3

[PATCH net-next v3 2/5] ethtool: Implements ETHTOOL_PHY_GTUNABLE/ETHTOOL_PHY_STUNABLE

[Allan W. Nielsen]

From: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>

Adding get_tunable/set_tunable function pointer to the phy_driver
structure, and uses these function pointers to implement the
ETHTOOL_PHY_GTUNABLE/ETHTOOL_PHY_STUNABLE ioctls.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Allan W. Nielsen <allan.nielsen@microsemi.com>
---
 include/linux/phy.h |  7 +++++
 net/core/ethtool.c  | 87 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 94 insertions(+)

diff --git a/include/linux/phy.h b/include/linux/phy.h
index 9880d73..3d35c36 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -611,6 +611,13 @@ struct phy_driver {
 	void (*get_strings)(struct phy_device *dev, u8 *data);
 	void (*get_stats)(struct phy_device *dev,
 			  struct ethtool_stats *stats, u64 *data);
+
+	/* Get and Set PHY tunables */
+	int (*get_tunable)(struct phy_device *dev,
+			   struct ethtool_tunable *tuna, void *data);
+	int (*set_tunable)(struct phy_device *dev,
+			    struct ethtool_tunable *tuna,
+			    const void *data);
 };
 #define to_phy_driver(d) container_of(to_mdio_common_driver(d),		\
 				      struct phy_driver, mdiodrv)
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 9774898..61aebdf 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -119,6 +119,11 @@ tunable_strings[__ETHTOOL_TUNABLE_COUNT][ETH_GSTRING_LEN] = {
 	[ETHTOOL_TX_COPYBREAK]	= "tx-copybreak",
 };
 
+static const char
+phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN] = {
+	[ETHTOOL_ID_UNSPEC]     = "Unspec",
+};
+
 static int ethtool_get_features(struct net_device *dev, void __user *useraddr)
 {
 	struct ethtool_gfeatures cmd = {
@@ -227,6 +232,9 @@ static int __ethtool_get_sset_count(struct net_device *dev, int sset)
 	if (sset == ETH_SS_TUNABLES)
 		return ARRAY_SIZE(tunable_strings);
 
+	if (sset == ETH_SS_PHY_TUNABLES)
+		return ARRAY_SIZE(phy_tunable_strings);
+
 	if (sset == ETH_SS_PHY_STATS) {
 		if (dev->phydev)
 			return phy_get_sset_count(dev->phydev);
@@ -253,6 +261,8 @@ static void __ethtool_get_strings(struct net_device *dev,
 		       sizeof(rss_hash_func_strings));
 	else if (stringset == ETH_SS_TUNABLES)
 		memcpy(data, tunable_strings, sizeof(tunable_strings));
+	else if (stringset == ETH_SS_PHY_TUNABLES)
+		memcpy(data, phy_tunable_strings, sizeof(phy_tunable_strings));
 	else if (stringset == ETH_SS_PHY_STATS) {
 		struct phy_device *phydev = dev->phydev;
 
@@ -2422,6 +2432,76 @@ static int ethtool_set_per_queue(struct net_device *dev, void __user *useraddr)
 	};
 }
 
+static int ethtool_phy_tunable_valid(const struct ethtool_tunable *tuna)
+{
+	switch (tuna->id) {
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int get_phy_tunable(struct net_device *dev, void __user *useraddr)
+{
+	int ret;
+	struct ethtool_tunable tuna;
+	struct phy_device *phydev = dev->phydev;
+	void *data;
+
+	if (!(phydev && phydev->drv && phydev->drv->get_tunable))
+		return -EOPNOTSUPP;
+
+	if (copy_from_user(&tuna, useraddr, sizeof(tuna)))
+		return -EFAULT;
+	ret = ethtool_phy_tunable_valid(&tuna);
+	if (ret)
+		return ret;
+	data = kmalloc(tuna.len, GFP_USER);
+	if (!data)
+		return -ENOMEM;
+	ret = phydev->drv->get_tunable(phydev, &tuna, data);
+	if (ret)
+		goto out;
+	useraddr += sizeof(tuna);
+	ret = -EFAULT;
+	if (copy_to_user(useraddr, data, tuna.len))
+		goto out;
+	ret = 0;
+
+out:
+	kfree(data);
+	return ret;
+}
+
+static int set_phy_tunable(struct net_device *dev, void __user *useraddr)
+{
+	int ret;
+	struct ethtool_tunable tuna;
+	struct phy_device *phydev = dev->phydev;
+	void *data;
+
+	if (!(phydev && phydev->drv && phydev->drv->set_tunable))
+		return -EOPNOTSUPP;
+	if (copy_from_user(&tuna, useraddr, sizeof(tuna)))
+		return -EFAULT;
+	ret = ethtool_phy_tunable_valid(&tuna);
+	if (ret)
+		return ret;
+	data = kmalloc(tuna.len, GFP_USER);
+	if (!data)
+		return -ENOMEM;
+	useraddr += sizeof(tuna);
+	ret = -EFAULT;
+	if (copy_from_user(data, useraddr, tuna.len))
+		goto out;
+	ret = phydev->drv->set_tunable(phydev, &tuna, data);
+
+out:
+	kfree(data);
+	return ret;
+}
+
 /* The main entry point in this file.  Called from net/core/dev_ioctl.c */
 
 int dev_ethtool(struct net *net, struct ifreq *ifr)
@@ -2479,6 +2559,7 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_GET_TS_INFO:
 	case ETHTOOL_GEEE:
 	case ETHTOOL_GTUNABLE:
+	case ETHTOOL_PHY_GTUNABLE:
 		break;
 	default:
 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
@@ -2684,6 +2765,12 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_SLINKSETTINGS:
 		rc = ethtool_set_link_ksettings(dev, useraddr);
 		break;
+	case ETHTOOL_PHY_GTUNABLE:
+		rc = get_phy_tunable(dev, useraddr);
+		break;
+	case ETHTOOL_PHY_STUNABLE:
+		rc = set_phy_tunable(dev, useraddr);
+		break;
 	default:
 		rc = -EOPNOTSUPP;
 	}
-- 
2.7.3

[PATCH net-next v3 3/5] ethtool: (uapi) Add ETHTOOL_PHY_DOWNSHIFT to PHY tunables

[Allan W. Nielsen]

From: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>

For operation in cabling environments that are incompatible with
1000BASE-T, PHY device may provide an automatic link speed downshift
operation. When enabled, the device automatically changes its 1000BASE-T
auto-negotiation to the next slower speed after a configured number of
failed attempts at 1000BASE-T.  This feature is useful in setting up in
networks using older cable installations that include only pairs A and B,
and not pairs C and D.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Signed-off-by: Allan W. Nielsen <allan.nielsen@microsemi.com>
---
 include/uapi/linux/ethtool.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 42f696f..f0db778 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -248,9 +248,12 @@ struct ethtool_tunable {
 	void	*data[0];
 };
 
+#define DOWNSHIFT_DEV_DEFAULT_COUNT	0xff
+#define DOWNSHIFT_DEV_DISABLE		0
+
 enum phy_tunable_id {
 	ETHTOOL_PHY_ID_UNSPEC,
-
+	ETHTOOL_PHY_DOWNSHIFT,
 	/*
 	 * Add your fresh new phy tunable attribute above and remember to update
 	 * phy_tunable_strings[] in net/core/ethtool.c
-- 
2.7.3

[PATCH net-next v3 4/5] ethtool: Core impl for ETHTOOL_PHY_DOWNSHIFT tunable

[Allan W. Nielsen]

From: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>

Adding validation support for the ETHTOOL_PHY_DOWNSHIFT. Functional
implementation needs to be done in the individual PHY drivers.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Allan W. Nielsen <allan.nielsen@microsemi.com>
---
 net/core/ethtool.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 61aebdf..e9b45567 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -122,6 +122,7 @@ tunable_strings[__ETHTOOL_TUNABLE_COUNT][ETH_GSTRING_LEN] = {
 static const char
 phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN] = {
 	[ETHTOOL_ID_UNSPEC]     = "Unspec",
+	[ETHTOOL_PHY_DOWNSHIFT]	= "phy-downshift",
 };
 
 static int ethtool_get_features(struct net_device *dev, void __user *useraddr)
@@ -2435,6 +2436,11 @@ static int ethtool_set_per_queue(struct net_device *dev, void __user *useraddr)
 static int ethtool_phy_tunable_valid(const struct ethtool_tunable *tuna)
 {
 	switch (tuna->id) {
+	case ETHTOOL_PHY_DOWNSHIFT:
+		if (tuna->len != sizeof(u8) ||
+		    tuna->type_id != ETHTOOL_TUNABLE_U8)
+			return -EINVAL;
+		break;
 	default:
 		return -EINVAL;
 	}
-- 
2.7.3

[PATCH net-next v3 5/5] net: phy: Add downshift get/set support in Microsemi PHYs driver

[Allan W. Nielsen]

From: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>

Implements the phy tunable function pointers and implement downshift
functionality for MSCC PHYs.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Allan W. Nielsen <allan.nielsen@microsemi.com>
---
 drivers/net/phy/mscc.c | 100 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 100 insertions(+)

diff --git a/drivers/net/phy/mscc.c b/drivers/net/phy/mscc.c
index d0026ab..92018ba 100644
--- a/drivers/net/phy/mscc.c
+++ b/drivers/net/phy/mscc.c
@@ -46,8 +46,15 @@ enum rgmii_rx_clock_delay {
 
 #define MSCC_EXT_PAGE_ACCESS		  31
 #define MSCC_PHY_PAGE_STANDARD		  0x0000 /* Standard registers */
+#define MSCC_PHY_PAGE_EXTENDED		  0x0001 /* Extended registers */
 #define MSCC_PHY_PAGE_EXTENDED_2	  0x0002 /* Extended reg - page 2 */
 
+/* Extended Page 1 Registers */
+#define MSCC_PHY_ACTIPHY_CNTL		  20
+#define DOWNSHIFT_CNTL_MASK		  0x001C
+#define DOWNSHIFT_EN			  0x0010
+#define DOWNSHIFT_CNTL_POS		  2
+
 /* Extended Page 2 Registers */
 #define MSCC_PHY_RGMII_CNTL		  20
 #define RGMII_RX_CLK_DELAY_MASK		  0x0070
@@ -75,6 +82,8 @@ enum rgmii_rx_clock_delay {
 #define MSCC_VDDMAC_2500		  2500
 #define MSCC_VDDMAC_3300		  3300
 
+#define DOWNSHIFT_COUNT_MAX		  5
+
 struct vsc8531_private {
 	int rate_magic;
 };
@@ -101,6 +110,66 @@ static int vsc85xx_phy_page_set(struct phy_device *phydev, u8 page)
 	return rc;
 }
 
+static int vsc85xx_downshift_get(struct phy_device *phydev, u8 *count)
+{
+	int rc;
+	u16 reg_val;
+
+	mutex_lock(&phydev->lock);
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_EXTENDED);
+	if (rc != 0)
+		goto out_unlock;
+
+	reg_val = phy_read(phydev, MSCC_PHY_ACTIPHY_CNTL);
+	reg_val &= DOWNSHIFT_CNTL_MASK;
+	if (!(reg_val & DOWNSHIFT_EN))
+		*count = DOWNSHIFT_DEV_DISABLE;
+	else
+		*count = ((reg_val & ~DOWNSHIFT_EN) >> DOWNSHIFT_CNTL_POS) + 2;
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_STANDARD);
+
+out_unlock:
+	mutex_unlock(&phydev->lock);
+
+	return rc;
+}
+
+static int vsc85xx_downshift_set(struct phy_device *phydev, u8 count)
+{
+	int rc;
+	u16 reg_val;
+
+	if (count == DOWNSHIFT_DEV_DEFAULT_COUNT) {
+		/* Default downshift count 3 (i.e. Bit3:2 = 0b01) */
+		count = ((1 << DOWNSHIFT_CNTL_POS) | DOWNSHIFT_EN);
+	} else if (count > DOWNSHIFT_COUNT_MAX || count == 1) {
+		phydev_err(phydev, "Downshift count should be 2,3,4 or 5\n");
+		return -ERANGE;
+	} else if (count) {
+		/* Downshift count is either 2,3,4 or 5 */
+		count = (((count - 2) << DOWNSHIFT_CNTL_POS) | DOWNSHIFT_EN);
+	}
+
+	mutex_lock(&phydev->lock);
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_EXTENDED);
+	if (rc != 0)
+		goto out_unlock;
+
+	reg_val = phy_read(phydev, MSCC_PHY_ACTIPHY_CNTL);
+	reg_val &= ~(DOWNSHIFT_CNTL_MASK);
+	reg_val |= count;
+	rc = phy_write(phydev, MSCC_PHY_ACTIPHY_CNTL, reg_val);
+	if (rc != 0)
+		goto out_unlock;
+
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_STANDARD);
+
+out_unlock:
+	mutex_unlock(&phydev->lock);
+
+	return rc;
+}
+
 static int vsc85xx_wol_set(struct phy_device *phydev,
 			   struct ethtool_wolinfo *wol)
 {
@@ -329,6 +398,29 @@ static int vsc85xx_default_config(struct phy_device *phydev)
 	return rc;
 }
 
+static int vsc85xx_get_tunable(struct phy_device *phydev,
+			       struct ethtool_tunable *tuna, void *data)
+{
+	switch (tuna->id) {
+	case ETHTOOL_PHY_DOWNSHIFT:
+		return vsc85xx_downshift_get(phydev, (u8 *)data);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int vsc85xx_set_tunable(struct phy_device *phydev,
+			       struct ethtool_tunable *tuna,
+			       const void *data)
+{
+	switch (tuna->id) {
+	case ETHTOOL_PHY_DOWNSHIFT:
+		return vsc85xx_downshift_set(phydev, *(u8 *)data);
+	default:
+		return -EINVAL;
+	}
+}
+
 static int vsc85xx_config_init(struct phy_device *phydev)
 {
 	int rc;
@@ -418,6 +510,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 },
 {
 	.phy_id		= PHY_ID_VSC8531,
@@ -437,6 +531,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 },
 {
 	.phy_id		= PHY_ID_VSC8540,
@@ -456,6 +552,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 },
 {
 	.phy_id		= PHY_ID_VSC8541,
@@ -475,6 +573,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 }
 
 };
-- 
2.7.3

Re: [PATCH net-next v3 3/5] ethtool: (uapi) Add ETHTOOL_PHY_DOWNSHIFT to PHY tunables

[Andrew Lunn]

On Tue, Nov 15, 2016 at 11:20:02AM +0100, Allan W. Nielsen wrote:
> From: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
> 
> For operation in cabling environments that are incompatible with
> 1000BASE-T, PHY device may provide an automatic link speed downshift
> operation. When enabled, the device automatically changes its 1000BASE-T
> auto-negotiation to the next slower speed after a configured number of
> failed attempts at 1000BASE-T.  This feature is useful in setting up in
> networks using older cable installations that include only pairs A and B,
> and not pairs C and D.
> 
> Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
> Signed-off-by: Allan W. Nielsen <allan.nielsen@microsemi.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew

Re: [PATCH net-next v3 0/5] Adding PHY-Tunables and downshift support

[David Miller]

From: "Allan W. Nielsen" <allan.nielsen@microsemi.com>
Date: Tue, 15 Nov 2016 11:19:59 +0100

> Old cover letters included below.

Please do not form your cover letter by quoting older and older
cover letters.

Always write a clean, single, cover letter with a changelog of
changed between each and every version leading up to the
current one.

Thank you.

[PATCH net-next v3 5/5] net: phy: Add downshift get/set support in Microsemi PHYs driver

[Allan W. Nielsen]

From: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>

Implements the phy tunable function pointers and implement downshift
functionality for MSCC PHYs.

Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microsemi.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Allan W. Nielsen <allan.nielsen@microsemi.com>
---
 drivers/net/phy/mscc.c | 100 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 100 insertions(+)

diff --git a/drivers/net/phy/mscc.c b/drivers/net/phy/mscc.c
index d0026ab..92018ba 100644
--- a/drivers/net/phy/mscc.c
+++ b/drivers/net/phy/mscc.c
@@ -46,8 +46,15 @@ enum rgmii_rx_clock_delay {
 
 #define MSCC_EXT_PAGE_ACCESS		  31
 #define MSCC_PHY_PAGE_STANDARD		  0x0000 /* Standard registers */
+#define MSCC_PHY_PAGE_EXTENDED		  0x0001 /* Extended registers */
 #define MSCC_PHY_PAGE_EXTENDED_2	  0x0002 /* Extended reg - page 2 */
 
+/* Extended Page 1 Registers */
+#define MSCC_PHY_ACTIPHY_CNTL		  20
+#define DOWNSHIFT_CNTL_MASK		  0x001C
+#define DOWNSHIFT_EN			  0x0010
+#define DOWNSHIFT_CNTL_POS		  2
+
 /* Extended Page 2 Registers */
 #define MSCC_PHY_RGMII_CNTL		  20
 #define RGMII_RX_CLK_DELAY_MASK		  0x0070
@@ -75,6 +82,8 @@ enum rgmii_rx_clock_delay {
 #define MSCC_VDDMAC_2500		  2500
 #define MSCC_VDDMAC_3300		  3300
 
+#define DOWNSHIFT_COUNT_MAX		  5
+
 struct vsc8531_private {
 	int rate_magic;
 };
@@ -101,6 +110,66 @@ static int vsc85xx_phy_page_set(struct phy_device *phydev, u8 page)
 	return rc;
 }
 
+static int vsc85xx_downshift_get(struct phy_device *phydev, u8 *count)
+{
+	int rc;
+	u16 reg_val;
+
+	mutex_lock(&phydev->lock);
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_EXTENDED);
+	if (rc != 0)
+		goto out_unlock;
+
+	reg_val = phy_read(phydev, MSCC_PHY_ACTIPHY_CNTL);
+	reg_val &= DOWNSHIFT_CNTL_MASK;
+	if (!(reg_val & DOWNSHIFT_EN))
+		*count = DOWNSHIFT_DEV_DISABLE;
+	else
+		*count = ((reg_val & ~DOWNSHIFT_EN) >> DOWNSHIFT_CNTL_POS) + 2;
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_STANDARD);
+
+out_unlock:
+	mutex_unlock(&phydev->lock);
+
+	return rc;
+}
+
+static int vsc85xx_downshift_set(struct phy_device *phydev, u8 count)
+{
+	int rc;
+	u16 reg_val;
+
+	if (count == DOWNSHIFT_DEV_DEFAULT_COUNT) {
+		/* Default downshift count 3 (i.e. Bit3:2 = 0b01) */
+		count = ((1 << DOWNSHIFT_CNTL_POS) | DOWNSHIFT_EN);
+	} else if (count > DOWNSHIFT_COUNT_MAX || count == 1) {
+		phydev_err(phydev, "Downshift count should be 2,3,4 or 5\n");
+		return -ERANGE;
+	} else if (count) {
+		/* Downshift count is either 2,3,4 or 5 */
+		count = (((count - 2) << DOWNSHIFT_CNTL_POS) | DOWNSHIFT_EN);
+	}
+
+	mutex_lock(&phydev->lock);
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_EXTENDED);
+	if (rc != 0)
+		goto out_unlock;
+
+	reg_val = phy_read(phydev, MSCC_PHY_ACTIPHY_CNTL);
+	reg_val &= ~(DOWNSHIFT_CNTL_MASK);
+	reg_val |= count;
+	rc = phy_write(phydev, MSCC_PHY_ACTIPHY_CNTL, reg_val);
+	if (rc != 0)
+		goto out_unlock;
+
+	rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_STANDARD);
+
+out_unlock:
+	mutex_unlock(&phydev->lock);
+
+	return rc;
+}
+
 static int vsc85xx_wol_set(struct phy_device *phydev,
 			   struct ethtool_wolinfo *wol)
 {
@@ -329,6 +398,29 @@ static int vsc85xx_default_config(struct phy_device *phydev)
 	return rc;
 }
 
+static int vsc85xx_get_tunable(struct phy_device *phydev,
+			       struct ethtool_tunable *tuna, void *data)
+{
+	switch (tuna->id) {
+	case ETHTOOL_PHY_DOWNSHIFT:
+		return vsc85xx_downshift_get(phydev, (u8 *)data);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int vsc85xx_set_tunable(struct phy_device *phydev,
+			       struct ethtool_tunable *tuna,
+			       const void *data)
+{
+	switch (tuna->id) {
+	case ETHTOOL_PHY_DOWNSHIFT:
+		return vsc85xx_downshift_set(phydev, *(u8 *)data);
+	default:
+		return -EINVAL;
+	}
+}
+
 static int vsc85xx_config_init(struct phy_device *phydev)
 {
 	int rc;
@@ -418,6 +510,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 },
 {
 	.phy_id		= PHY_ID_VSC8531,
@@ -437,6 +531,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 },
 {
 	.phy_id		= PHY_ID_VSC8540,
@@ -456,6 +552,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 },
 {
 	.phy_id		= PHY_ID_VSC8541,
@@ -475,6 +573,8 @@ static struct phy_driver vsc85xx_driver[] = {
 	.probe		= &vsc85xx_probe,
 	.set_wol	= &vsc85xx_wol_set,
 	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
 }
 
 };
-- 
2.7.3