Merge branch 'Raw-PHY-TDR-data'

Andrew Lunn says:

====================
Raw PHY TDR data

Some ethernet PHYs allow access to raw TDR data in addition to summary
diagnostics information. Add support for retrieving this data via
netlink ethtool. The basic structure in the core is the same as for
normal phy diagnostics, the PHY driver simply uses different helpers
to fill the netlink message with different data.

There is a graphical tool under development, as well a ethtool(1)
which can dump the data as text and JSON.

A patched ethtool(1) can be found in
https://github.com/lunn/ethtool.git feature/cable-test-v5

Thanks for Chris Healy for lots of testing.

v2:
See the individual patches but:

Pass distances in centimeters, not meters

Allow the PHY to round distances to what it supports and report what
it actually used along with the results.

Make the Marvell PHY use steps a multiple of 0.805 meters, its native
step size.

v3:
Move the TDR configuration into a structure
Add a range check on step
Use NL_SET_ERR_MSG_ATTR() when appropriate
Move TDR configuration into a nest
Document attributes in the request
Unsquash the last two patches
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 284 insertions, 1 deletions

diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index 4bc7febf9248..2c04e3b2b285 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -42,6 +42,7 @@
 #define MII_MARVELL_FIBER_PAGE		0x01
 #define MII_MARVELL_MSCR_PAGE		0x02
 #define MII_MARVELL_LED_PAGE		0x03
+#define MII_MARVELL_VCT5_PAGE		0x05
 #define MII_MARVELL_MISC_TEST_PAGE	0x06
 #define MII_MARVELL_VCT7_PAGE		0x07
 #define MII_MARVELL_WOL_PAGE		0x11
@@ -164,6 +165,60 @@
 #define MII_88E1510_GEN_CTRL_REG_1_MODE_SGMII	0x1	/* SGMII to copper */
 #define MII_88E1510_GEN_CTRL_REG_1_RESET	0x8000	/* Soft reset */
 
+#define MII_VCT5_TX_RX_MDI0_COUPLING	0x10
+#define MII_VCT5_TX_RX_MDI1_COUPLING	0x11
+#define MII_VCT5_TX_RX_MDI2_COUPLING	0x12
+#define MII_VCT5_TX_RX_MDI3_COUPLING	0x13
+#define MII_VCT5_TX_RX_AMPLITUDE_MASK	0x7f00
+#define MII_VCT5_TX_RX_AMPLITUDE_SHIFT	8
+#define MII_VCT5_TX_RX_COUPLING_POSITIVE_REFLECTION	BIT(15)
+
+#define MII_VCT5_CTRL				0x17
+#define MII_VCT5_CTRL_ENABLE				BIT(15)
+#define MII_VCT5_CTRL_COMPLETE				BIT(14)
+#define MII_VCT5_CTRL_TX_SAME_CHANNEL			(0x0 << 11)
+#define MII_VCT5_CTRL_TX0_CHANNEL			(0x4 << 11)
+#define MII_VCT5_CTRL_TX1_CHANNEL			(0x5 << 11)
+#define MII_VCT5_CTRL_TX2_CHANNEL			(0x6 << 11)
+#define MII_VCT5_CTRL_TX3_CHANNEL			(0x7 << 11)
+#define MII_VCT5_CTRL_SAMPLES_2				(0x0 << 8)
+#define MII_VCT5_CTRL_SAMPLES_4				(0x1 << 8)
+#define MII_VCT5_CTRL_SAMPLES_8				(0x2 << 8)
+#define MII_VCT5_CTRL_SAMPLES_16			(0x3 << 8)
+#define MII_VCT5_CTRL_SAMPLES_32			(0x4 << 8)
+#define MII_VCT5_CTRL_SAMPLES_64			(0x5 << 8)
+#define MII_VCT5_CTRL_SAMPLES_128			(0x6 << 8)
+#define MII_VCT5_CTRL_SAMPLES_DEFAULT			(0x6 << 8)
+#define MII_VCT5_CTRL_SAMPLES_256			(0x7 << 8)
+#define MII_VCT5_CTRL_SAMPLES_SHIFT			8
+#define MII_VCT5_CTRL_MODE_MAXIMUM_PEEK			(0x0 << 6)
+#define MII_VCT5_CTRL_MODE_FIRST_LAST_PEEK		(0x1 << 6)
+#define MII_VCT5_CTRL_MODE_OFFSET			(0x2 << 6)
+#define MII_VCT5_CTRL_SAMPLE_POINT			(0x3 << 6)
+#define MII_VCT5_CTRL_PEEK_HYST_DEFAULT			3
+
+#define MII_VCT5_SAMPLE_POINT_DISTANCE		0x18
+#define MII_VCT5_SAMPLE_POINT_DISTANCE_MAX	511
+#define MII_VCT5_TX_PULSE_CTRL			0x1c
+#define MII_VCT5_TX_PULSE_CTRL_DONT_WAIT_LINK_DOWN	BIT(12)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_128nS	(0x0 << 10)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_96nS		(0x1 << 10)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_64nS		(0x2 << 10)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_32nS		(0x3 << 10)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_SHIFT	10
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_AMPLITUDE_1000mV	(0x0 << 8)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_AMPLITUDE_750mV	(0x1 << 8)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_AMPLITUDE_500mV	(0x2 << 8)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_AMPLITUDE_250mV	(0x3 << 8)
+#define MII_VCT5_TX_PULSE_CTRL_PULSE_AMPLITUDE_SHIFT	8
+#define MII_VCT5_TX_PULSE_CTRL_MAX_AMP			BIT(7)
+#define MII_VCT5_TX_PULSE_CTRL_GT_140m_46_86mV		(0x6 << 0)
+
+/* For TDR measurements less than 11 meters, a short pulse should be
+ * used.
+ */
+#define TDR_SHORT_CABLE_LENGTH	11
+
 #define MII_VCT7_PAIR_0_DISTANCE	0x10
 #define MII_VCT7_PAIR_1_DISTANCE	0x11
 #define MII_VCT7_PAIR_2_DISTANCE	0x12
@@ -220,6 +275,11 @@ struct marvell_priv {
 	u64 stats[ARRAY_SIZE(marvell_hw_stats)];
 	char *hwmon_name;
 	struct device *hwmon_dev;
+	bool cable_test_tdr;
+	u32 first;
+	u32 last;
+	u32 step;
+	s8 pair;
 };
 
 static int marvell_read_page(struct phy_device *phydev)
@@ -1690,7 +1750,150 @@ static void marvell_get_stats(struct phy_device *phydev,
 		data[i] = marvell_get_stat(phydev, i);
 }
 
-static int marvell_vct7_cable_test_start(struct phy_device *phydev)
+static int marvell_vct5_wait_complete(struct phy_device *phydev)
+{
+	int i;
+	int val;
+
+	for (i = 0; i < 32; i++) {
+		val = __phy_read(phydev, MII_VCT5_CTRL);
+		if (val < 0)
+			return val;
+
+		if (val & MII_VCT5_CTRL_COMPLETE)
+			return 0;
+	}
+
+	phydev_err(phydev, "Timeout while waiting for cable test to finish\n");
+	return -ETIMEDOUT;
+}
+
+static int marvell_vct5_amplitude(struct phy_device *phydev, int pair)
+{
+	int amplitude;
+	int val;
+	int reg;
+
+	reg = MII_VCT5_TX_RX_MDI0_COUPLING + pair;
+	val = __phy_read(phydev, reg);
+
+	if (val < 0)
+		return 0;
+
+	amplitude = (val & MII_VCT5_TX_RX_AMPLITUDE_MASK) >>
+		MII_VCT5_TX_RX_AMPLITUDE_SHIFT;
+
+	if (!(val & MII_VCT5_TX_RX_COUPLING_POSITIVE_REFLECTION))
+		amplitude = -amplitude;
+
+	return 1000 * amplitude / 128;
+}
+
+static u32 marvell_vct5_distance2cm(int distance)
+{
+	return distance * 805 / 10;
+}
+
+static u32 marvell_vct5_cm2distance(int cm)
+{
+	return cm * 10 / 805;
+}
+
+static int marvell_vct5_amplitude_distance(struct phy_device *phydev,
+					   int distance, int pair)
+{
+	u16 reg;
+	int err;
+	int mV;
+	int i;
+
+	err = __phy_write(phydev, MII_VCT5_SAMPLE_POINT_DISTANCE,
+			  distance);
+	if (err)
+		return err;
+
+	reg = MII_VCT5_CTRL_ENABLE |
+		MII_VCT5_CTRL_TX_SAME_CHANNEL |
+		MII_VCT5_CTRL_SAMPLES_DEFAULT |
+		MII_VCT5_CTRL_SAMPLE_POINT |
+		MII_VCT5_CTRL_PEEK_HYST_DEFAULT;
+	err = __phy_write(phydev, MII_VCT5_CTRL, reg);
+	if (err)
+		return err;
+
+	err = marvell_vct5_wait_complete(phydev);
+	if (err)
+		return err;
+
+	for (i = 0; i < 4; i++) {
+		if (pair != PHY_PAIR_ALL && i != pair)
+			continue;
+
+		mV = marvell_vct5_amplitude(phydev, i);
+		ethnl_cable_test_amplitude(phydev, i, mV);
+	}
+
+	return 0;
+}
+
+static int marvell_vct5_amplitude_graph(struct phy_device *phydev)
+{
+	struct marvell_priv *priv = phydev->priv;
+	int distance;
+	u16 width;
+	int page;
+	int err;
+	u16 reg;
+
+	if (priv->first <= TDR_SHORT_CABLE_LENGTH)
+		width = MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_32nS;
+	else
+		width = MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_128nS;
+
+	reg = MII_VCT5_TX_PULSE_CTRL_GT_140m_46_86mV |
+		MII_VCT5_TX_PULSE_CTRL_DONT_WAIT_LINK_DOWN |
+		MII_VCT5_TX_PULSE_CTRL_MAX_AMP | width;
+
+	err = phy_write_paged(phydev, MII_MARVELL_VCT5_PAGE,
+			      MII_VCT5_TX_PULSE_CTRL, reg);
+	if (err)
+		return err;
+
+	/* Reading the TDR data is very MDIO heavy. We need to optimize
+	 * access to keep the time to a minimum. So lock the bus once,
+	 * and don't release it until complete. We can then avoid having
+	 * to change the page for every access, greatly speeding things
+	 * up.
+	 */
+	page = phy_select_page(phydev, MII_MARVELL_VCT5_PAGE);
+	if (page < 0)
+		return page;
+
+	for (distance = priv->first;
+	     distance <= priv->last;
+	     distance += priv->step) {
+		err = marvell_vct5_amplitude_distance(phydev, distance,
+						      priv->pair);
+		if (err)
+			goto restore_page;
+
+		if (distance > TDR_SHORT_CABLE_LENGTH &&
+		    width == MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_32nS) {
+			width = MII_VCT5_TX_PULSE_CTRL_PULSE_WIDTH_128nS;
+			reg = MII_VCT5_TX_PULSE_CTRL_GT_140m_46_86mV |
+				MII_VCT5_TX_PULSE_CTRL_DONT_WAIT_LINK_DOWN |
+				MII_VCT5_TX_PULSE_CTRL_MAX_AMP | width;
+			err = __phy_write(phydev, MII_VCT5_TX_PULSE_CTRL, reg);
+			if (err)
+				goto restore_page;
+		}
+	}
+
+restore_page:
+	return phy_restore_page(phydev, page, err);
+}
+
+static int marvell_cable_test_start_common(struct phy_device *phydev)
 {
 	int bmcr, bmsr, ret;
 
@@ -1719,12 +1922,81 @@ static int marvell_vct7_cable_test_start(struct phy_device *phydev)
 	if (bmsr & BMSR_LSTATUS)
 		msleep(1500);
 
+	return 0;
+}
+
+static int marvell_vct7_cable_test_start(struct phy_device *phydev)
+{
+	struct marvell_priv *priv = phydev->priv;
+	int ret;
+
+	ret = marvell_cable_test_start_common(phydev);
+	if (ret)
+		return ret;
+
+	priv->cable_test_tdr = false;
+
+	/* Reset the VCT5 API control to defaults, otherwise
+	 * VCT7 does not work correctly.
+	 */
+	ret = phy_write_paged(phydev, MII_MARVELL_VCT5_PAGE,
+			      MII_VCT5_CTRL,
+			      MII_VCT5_CTRL_TX_SAME_CHANNEL |
+			      MII_VCT5_CTRL_SAMPLES_DEFAULT |
+			      MII_VCT5_CTRL_MODE_MAXIMUM_PEEK |
+			      MII_VCT5_CTRL_PEEK_HYST_DEFAULT);
+	if (ret)
+		return ret;
+
+	ret = phy_write_paged(phydev, MII_MARVELL_VCT5_PAGE,
+			      MII_VCT5_SAMPLE_POINT_DISTANCE, 0);
+	if (ret)
+		return ret;
+
 	return phy_write_paged(phydev, MII_MARVELL_VCT7_PAGE,
 			       MII_VCT7_CTRL,
 			       MII_VCT7_CTRL_RUN_NOW |
 			       MII_VCT7_CTRL_CENTIMETERS);
 }
 
+static int marvell_vct5_cable_test_tdr_start(struct phy_device *phydev,
+					     const struct phy_tdr_config *cfg)
+{
+	struct marvell_priv *priv = phydev->priv;
+	int ret;
+
+	priv->cable_test_tdr = true;
+	priv->first = marvell_vct5_cm2distance(cfg->first);
+	priv->last = marvell_vct5_cm2distance(cfg->last);
+	priv->step = marvell_vct5_cm2distance(cfg->step);
+	priv->pair = cfg->pair;
+
+	if (priv->first > MII_VCT5_SAMPLE_POINT_DISTANCE_MAX)
+		return -EINVAL;
+
+	if (priv->last > MII_VCT5_SAMPLE_POINT_DISTANCE_MAX)
+		return -EINVAL;
+
+	/* Disable  VCT7 */
+	ret = phy_write_paged(phydev, MII_MARVELL_VCT7_PAGE,
+			      MII_VCT7_CTRL, 0);
+	if (ret)
+		return ret;
+
+	ret = marvell_cable_test_start_common(phydev);
+	if (ret)
+		return ret;
+
+	ret = ethnl_cable_test_pulse(phydev, 1000);
+	if (ret)
+		return ret;
+
+	return ethnl_cable_test_step(phydev,
+				     marvell_vct5_distance2cm(priv->first),
+				     marvell_vct5_distance2cm(priv->last),
+				     marvell_vct5_distance2cm(priv->step));
+}
+
 static int marvell_vct7_distance_to_length(int distance, bool meter)
 {
 	if (meter)
@@ -1828,8 +2100,15 @@ static int marvell_vct7_cable_test_report(struct phy_device *phydev)
 static int marvell_vct7_cable_test_get_status(struct phy_device *phydev,
 					      bool *finished)
 {
+	struct marvell_priv *priv = phydev->priv;
 	int ret;
 
+	if (priv->cable_test_tdr) {
+		ret = marvell_vct5_amplitude_graph(phydev);
+		*finished = true;
+		return ret;
+	}
+
 	*finished = false;
 
 	ret = phy_read_paged(phydev, MII_MARVELL_VCT7_PAGE,
@@ -2563,6 +2842,7 @@ static struct phy_driver marvell_drivers[] = {
 		.get_tunable = m88e1011_get_tunable,
 		.set_tunable = m88e1011_set_tunable,
 		.cable_test_start = marvell_vct7_cable_test_start,
+		.cable_test_tdr_start = marvell_vct5_cable_test_tdr_start,
 		.cable_test_get_status = marvell_vct7_cable_test_get_status,
 	},
 	{
@@ -2588,6 +2868,7 @@ static struct phy_driver marvell_drivers[] = {
 		.get_tunable = m88e1540_get_tunable,
 		.set_tunable = m88e1540_set_tunable,
 		.cable_test_start = marvell_vct7_cable_test_start,
+		.cable_test_tdr_start = marvell_vct5_cable_test_tdr_start,
 		.cable_test_get_status = marvell_vct7_cable_test_get_status,
 	},
 	{
@@ -2613,6 +2894,7 @@ static struct phy_driver marvell_drivers[] = {
 		.get_tunable = m88e1540_get_tunable,
 		.set_tunable = m88e1540_set_tunable,
 		.cable_test_start = marvell_vct7_cable_test_start,
+		.cable_test_tdr_start = marvell_vct5_cable_test_tdr_start,
 		.cable_test_get_status = marvell_vct7_cable_test_get_status,
 	},
 	{
@@ -2658,6 +2940,7 @@ static struct phy_driver marvell_drivers[] = {
 		.get_tunable = m88e1540_get_tunable,
 		.set_tunable = m88e1540_set_tunable,
 		.cable_test_start = marvell_vct7_cable_test_start,
+		.cable_test_tdr_start = marvell_vct5_cable_test_tdr_start,
 		.cable_test_get_status = marvell_vct7_cable_test_get_status,
 	},
 };