* [PATCH net-next 1/2] net: phy: phy-c45: add OATC14 10BASE-T1S PHY cable diagnostic support
2025-11-04 10:20 [PATCH net-next 0/2] net: phy: microchip_t1s: Add support for LAN867x Rev.D0 PHY Parthiban Veerasooran
@ 2025-11-04 10:20 ` Parthiban Veerasooran
2025-11-04 15:46 ` Andrew Lunn
2025-11-04 10:20 ` [PATCH net-next 2/2] net: phy: microchip_t1s:: add cable diagnostic support for LAN867x Rev.D0 Parthiban Veerasooran
1 sibling, 1 reply; 7+ messages in thread
From: Parthiban Veerasooran @ 2025-11-04 10:20 UTC (permalink / raw)
To: Parthiban.Veerasooran, piergiorgio.beruto, andrew, hkallweit1,
linux, davem, edumazet, kuba, pabeni
Cc: netdev, linux-kernel, Parthiban Veerasooran
Add support for Open Alliance TC14 (OATC14) 10BASE-T1S PHYs cable
diagnostic feature.
This patch implements:
- genphy_c45_oatc14_cable_test_start() to initiate a cable test
- genphy_c45_oatc14_cable_test_get_status() to retrieve test results
- Helper function to map PHY cable test status to ethtool result codes
- Function declarations and exports for use by PHY drivers
This enables ethtool to report ok, open, short, and undetectable cable
conditions on OATC14 10Base-T1S PHYs.
Open Alliance TC14 10BASE-T1S Advanced Diagnostic PHY Features
Specification ref:
https://opensig.org/wp-content/uploads/2025/06/OPEN_Alliance_10BASE-T1S_Advanced_PHY_features_for-automotive_Ethernet_V2.1b.pdf
Signed-off-by: Parthiban Veerasooran <parthiban.veerasooran@microchip.com>
---
drivers/net/phy/mdio-open-alliance.h | 36 ++++++++
drivers/net/phy/phy-c45.c | 122 +++++++++++++++++++++++++++
include/linux/phy.h | 3 +
3 files changed, 161 insertions(+)
diff --git a/drivers/net/phy/mdio-open-alliance.h b/drivers/net/phy/mdio-open-alliance.h
index 931e14660d75..db302ff1f39a 100644
--- a/drivers/net/phy/mdio-open-alliance.h
+++ b/drivers/net/phy/mdio-open-alliance.h
@@ -43,4 +43,40 @@
/* Version Identifiers */
#define OATC14_IDM 0x0a00
+/*
+ * Open Alliance TC14 (10BASE-T1S) - Advanced Diagnostic Features Registers
+ *
+ * Refer to the OPEN Alliance documentation:
+ * https://opensig.org/automotive-ethernet-specifications/
+ *
+ * Specification:
+ * "10BASE-T1S Advanced Diagnostic PHY Features"
+ * https://opensig.org/wp-content/uploads/2025/06/OPEN_Alliance_10BASE-T1S_Advanced_PHY_features_for-automotive_Ethernet_V2.1b.pdf
+ */
+/* Advanced Diagnostic Features Capability Register*/
+#define MDIO_OATC14_ADFCAP 0xcc00
+#define OATC14_ADFCAP_HDD_CAPABILITY GENMASK(10, 8)
+
+/* Harness Defect Detection Register */
+#define MDIO_OATC14_HDD 0xcc01
+#define OATC14_HDD_CONTROL BIT(15)
+#define OATC14_HDD_READY BIT(14)
+#define OATC14_HDD_START_CONTROL BIT(13)
+#define OATC14_HDD_VALID BIT(2)
+#define OATC14_HDD_SHORT_OPEN_STATUS GENMASK(1, 0)
+
+/* Bus Short/Open Status:
+ * 0 0 - no fault; everything is ok. (Default)
+ * 0 1 - detected as an open or missing termination(s)
+ * 1 0 - detected as a short or extra termination(s)
+ * 1 1 - fault but fault type not detectable. More details can be available by
+ * vender specific register if supported.
+ */
+enum oatc14_hdd_status {
+ OATC14_HDD_STATUS_CABLE_OK,
+ OATC14_HDD_STATUS_OPEN,
+ OATC14_HDD_STATUS_SHORT,
+ OATC14_HDD_STATUS_NOT_DETECTABLE,
+};
+
#endif /* __MDIO_OPEN_ALLIANCE__ */
diff --git a/drivers/net/phy/phy-c45.c b/drivers/net/phy/phy-c45.c
index 61670be0f095..6030023bf840 100644
--- a/drivers/net/phy/phy-c45.c
+++ b/drivers/net/phy/phy-c45.c
@@ -7,6 +7,7 @@
#include <linux/mdio.h>
#include <linux/mii.h>
#include <linux/phy.h>
+#include <linux/ethtool_netlink.h>
#include "mdio-open-alliance.h"
#include "phylib-internal.h"
@@ -1573,3 +1574,124 @@ int genphy_c45_ethtool_set_eee(struct phy_device *phydev,
return ret;
}
EXPORT_SYMBOL(genphy_c45_ethtool_set_eee);
+
+/**
+ * oatc14_cable_test_get_result_code - Convert hardware cable test status to
+ * ethtool result code.
+ * @status: The hardware-reported cable test status
+ *
+ * This helper function maps the OATC14 HDD cable test status to the
+ * corresponding ethtool cable test result code. It provides a translation
+ * between the device-specific status values and the standardized ethtool
+ * result codes.
+ *
+ * Return:
+ * * ETHTOOL_A_CABLE_RESULT_CODE_OK - Cable is OK
+ * * ETHTOOL_A_CABLE_RESULT_CODE_OPEN - Open circuit detected
+ * * ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT - Short circuit detected
+ * * ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC - Status not detectable or invalid
+ */
+static int oatc14_cable_test_get_result_code(enum oatc14_hdd_status status)
+{
+ switch (status) {
+ case OATC14_HDD_STATUS_CABLE_OK:
+ return ETHTOOL_A_CABLE_RESULT_CODE_OK;
+ case OATC14_HDD_STATUS_OPEN:
+ return ETHTOOL_A_CABLE_RESULT_CODE_OPEN;
+ case OATC14_HDD_STATUS_SHORT:
+ return ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT;
+ case OATC14_HDD_STATUS_NOT_DETECTABLE:
+ default:
+ return ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC;
+ }
+}
+
+/**
+ * genphy_c45_oatc14_cable_test_get_status - Get status of OATC14 10Base-T1S
+ * PHY cable test.
+ * @phydev: pointer to the PHY device structure
+ * @finished: pointer to a boolean set true if the test is complete
+ *
+ * Retrieves the current status of the OATC14 10Base-T1S PHY cable test.
+ * This function reads the OATC14 HDD register to determine whether the test
+ * results are valid and whether the test has finished.
+ *
+ * If the test is complete, the function reports the cable test result via
+ * the ethtool cable test interface using ethnl_cable_test_result(), and then
+ * clears the test control bit in the PHY register to reset the test state.
+ *
+ * Return: 0 on success, or a negative error code on failure (e.g. register
+ * read/write error).
+ */
+int genphy_c45_oatc14_cable_test_get_status(struct phy_device *phydev,
+ bool *finished)
+{
+ int ret;
+ u8 sts;
+
+ *finished = false;
+
+ ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, MDIO_OATC14_HDD);
+ if (ret < 0)
+ return ret;
+
+ if (!(ret & OATC14_HDD_VALID))
+ return 0;
+
+ *finished = true;
+
+ sts = FIELD_GET(OATC14_HDD_SHORT_OPEN_STATUS, ret);
+
+ ret = ethnl_cable_test_result(phydev, ETHTOOL_A_CABLE_PAIR_A,
+ oatc14_cable_test_get_result_code(sts));
+ if (ret)
+ return ret;
+
+ return phy_clear_bits_mmd(phydev, MDIO_MMD_VEND2,
+ MDIO_OATC14_HDD, OATC14_HDD_CONTROL);
+}
+EXPORT_SYMBOL(genphy_c45_oatc14_cable_test_get_status);
+
+/**
+ * genphy_c45_oatc14_cable_test_start - Start a cable test on an OATC14
+ * 10Base-T1S PHY.
+ * @phydev: Pointer to the PHY device structure
+ *
+ * This function initiates a cable diagnostic test on a Clause 45 OATC14
+ * 10Base-T1S capable PHY device. It first reads the PHY’s advanced diagnostic
+ * capability register to check if High Definition Diagnostics (HDD) mode is
+ * supported. If the PHY does not report HDD capability, cable testing is not
+ * supported and the function returns -EOPNOTSUPP.
+ *
+ * For PHYs that support HDD, the function sets the appropriate control bits in
+ * the OATC14_HDD register to enable and start the cable diagnostic test.
+ *
+ * Return:
+ * * 0 on success
+ * * -EOPNOTSUPP if the PHY does not support HDD capability
+ * * A negative error code on I/O or register access failures
+ */
+int genphy_c45_oatc14_cable_test_start(struct phy_device *phydev)
+{
+ int ret;
+
+ ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, MDIO_OATC14_ADFCAP);
+ if (ret < 0)
+ return ret;
+
+ if (!(ret & OATC14_ADFCAP_HDD_CAPABILITY))
+ return -EOPNOTSUPP;
+
+ ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, MDIO_OATC14_HDD,
+ OATC14_HDD_CONTROL);
+ if (ret)
+ return ret;
+
+ ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, MDIO_OATC14_HDD);
+ if (ret < 0)
+ return ret;
+
+ return phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, MDIO_OATC14_HDD,
+ OATC14_HDD_START_CONTROL);
+}
+EXPORT_SYMBOL(genphy_c45_oatc14_cable_test_start);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index e3474f03cbc1..36457879c677 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -2251,6 +2251,9 @@ int genphy_c45_ethtool_get_eee(struct phy_device *phydev,
int genphy_c45_ethtool_set_eee(struct phy_device *phydev,
struct ethtool_keee *data);
int genphy_c45_an_config_eee_aneg(struct phy_device *phydev);
+int genphy_c45_oatc14_cable_test_start(struct phy_device *phydev);
+int genphy_c45_oatc14_cable_test_get_status(struct phy_device *phydev,
+ bool *finished);
/* The gen10g_* functions are the old Clause 45 stub */
int gen10g_config_aneg(struct phy_device *phydev);
--
2.34.1
^ permalink raw reply [flat|nested] 7+ messages in thread* [PATCH net-next 2/2] net: phy: microchip_t1s:: add cable diagnostic support for LAN867x Rev.D0
2025-11-04 10:20 [PATCH net-next 0/2] net: phy: microchip_t1s: Add support for LAN867x Rev.D0 PHY Parthiban Veerasooran
2025-11-04 10:20 ` [PATCH net-next 1/2] net: phy: phy-c45: add OATC14 10BASE-T1S PHY cable diagnostic support Parthiban Veerasooran
@ 2025-11-04 10:20 ` Parthiban Veerasooran
2025-11-04 15:48 ` Andrew Lunn
1 sibling, 1 reply; 7+ messages in thread
From: Parthiban Veerasooran @ 2025-11-04 10:20 UTC (permalink / raw)
To: Parthiban.Veerasooran, piergiorgio.beruto, andrew, hkallweit1,
linux, davem, edumazet, kuba, pabeni
Cc: netdev, linux-kernel, Parthiban Veerasooran
Enable Open Alliance TC14 (OATC14) 10Base-T1S cable diagnostic feature
for Microchip LAN867x Rev.D0 PHY by implementing `cable_test_start` and
`cable_test_get_status` using the generic C45 functions. This allows the
`ethtool` utility to perform cable diagnostic tests directly on the PHY,
improving network troubleshooting and maintenance.
Signed-off-by: Parthiban Veerasooran <parthiban.veerasooran@microchip.com>
---
drivers/net/phy/microchip_t1s.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/phy/microchip_t1s.c b/drivers/net/phy/microchip_t1s.c
index bce5cf087b19..dd3de712c9d4 100644
--- a/drivers/net/phy/microchip_t1s.c
+++ b/drivers/net/phy/microchip_t1s.c
@@ -573,6 +573,9 @@ static struct phy_driver microchip_t1s_driver[] = {
.get_plca_cfg = genphy_c45_plca_get_cfg,
.set_plca_cfg = lan86xx_plca_set_cfg,
.get_plca_status = genphy_c45_plca_get_status,
+ .cable_test_start = genphy_c45_oatc14_cable_test_start,
+ .cable_test_get_status =
+ genphy_c45_oatc14_cable_test_get_status,
},
{
PHY_ID_MATCH_EXACT(PHY_ID_LAN865X_REVB),
--
2.34.1
^ permalink raw reply [flat|nested] 7+ messages in thread