[PATCH v5 0/3] net: phy: bcm5481x: add support for BroadR-Reach mode

[PATCH v5 0/3] net: phy: bcm5481x: add support for BroadR-Reach mode

[Kamil Horák - 2N]

PATCH 1 - Add the 10baseT1BRR_Full link mode

PATCH 2 - Add the definitions of LRE registers, necessary to use
   BroadR-Reach modes on the BCM5481x PHY

PATCH 3 - Implementation of the BroadR-Reach modes for the Broadcom
   PHYs

Changes in v2:
  - Divided into multiple patches, removed useless link modes

Changes in v3:
  - Fixed uninitialized variable in bcm5481x_config_delay_swap function

Changes in v4:
  - Improved the division of functions between bcm-phy library and broadcom.c
  - Changed the BroadR-Reach / IEEE mode switching to device tree boolean as
    these modes are mutually exclusive and barely could coexist in one hardware
  - Made the link mode selection compatible with current ethtool (i.e. the
    linkmode is selected by choosing speed and master-slave)

Changes in v5:
  - Fixed the operator precedence as reported by the kernel test robot
  - Fixed doc of bcm_linkmode_adv_to_mii_adv_t function

Kamil Horák - 2N (3):
  net: phy: bcm54811: New link mode for BroadR-Reach
  net: phy: bcm54811: Add LRE registers definitions
  net: phy: bcm-phy-lib: Implement BroadR-Reach link modes

 drivers/net/phy/bcm-phy-lib.c | 123 ++++++++++++
 drivers/net/phy/bcm-phy-lib.h |   4 +
 drivers/net/phy/broadcom.c    | 368 ++++++++++++++++++++++++++++++++--
 drivers/net/phy/phy-core.c    |   3 +-
 include/linux/brcmphy.h       |  89 ++++++++
 include/uapi/linux/ethtool.h  |   1 +
 net/ethtool/common.c          |   3 +
 7 files changed, 573 insertions(+), 18 deletions(-)

-- 
2.39.2

[PATCH v5 1/3] net: phy: bcm54811: New link mode for BroadR-Reach

[Kamil Horák - 2N]

Introduce a new link mode necessary for 10 MBit single-pair
connection in BroadR-Reach mode on bcm5481x PHY by Broadcom.
This new link mode, 10baseT1BRR, is known as 1BR10 in the Broadcom
terminology. Another link mode to be used is 1BR100 and it is already
present as 100baseT1, because Broadcom's 1BR100 became 100baseT1
(IEEE 802.3bw).

Signed-off-by: Kamil Horák - 2N <kamilh@axis.com>
---
 drivers/net/phy/phy-core.c   | 1 +
 include/uapi/linux/ethtool.h | 1 +
 net/ethtool/common.c         | 3 +++
 3 files changed, 5 insertions(+)

diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c
index 15f349e5995a..4a1972e94107 100644
--- a/drivers/net/phy/phy-core.c
+++ b/drivers/net/phy/phy-core.c
@@ -265,6 +265,7 @@ static const struct phy_setting settings[] = {
 	PHY_SETTING(     10, FULL,     10baseT1S_Full		),
 	PHY_SETTING(     10, HALF,     10baseT1S_Half		),
 	PHY_SETTING(     10, HALF,     10baseT1S_P2MP_Half	),
+	PHY_SETTING(     10, FULL,     10baseT1BRR_Full		),
 };
 #undef PHY_SETTING
 
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 8733a3117902..76813ca5cb1d 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -1845,6 +1845,7 @@ enum ethtool_link_mode_bit_indices {
 	ETHTOOL_LINK_MODE_10baseT1S_Full_BIT		 = 99,
 	ETHTOOL_LINK_MODE_10baseT1S_Half_BIT		 = 100,
 	ETHTOOL_LINK_MODE_10baseT1S_P2MP_Half_BIT	 = 101,
+	ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT		 = 102,
 
 	/* must be last entry */
 	__ETHTOOL_LINK_MODE_MASK_NBITS
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 6b2a360dcdf0..82ba2ca98d4c 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -211,6 +211,7 @@ const char link_mode_names[][ETH_GSTRING_LEN] = {
 	__DEFINE_LINK_MODE_NAME(10, T1S, Full),
 	__DEFINE_LINK_MODE_NAME(10, T1S, Half),
 	__DEFINE_LINK_MODE_NAME(10, T1S_P2MP, Half),
+	__DEFINE_LINK_MODE_NAME(10, T1BRR, Full),
 };
 static_assert(ARRAY_SIZE(link_mode_names) == __ETHTOOL_LINK_MODE_MASK_NBITS);
 
@@ -251,6 +252,7 @@ static_assert(ARRAY_SIZE(link_mode_names) == __ETHTOOL_LINK_MODE_MASK_NBITS);
 #define __LINK_MODE_LANES_T1S_P2MP	1
 #define __LINK_MODE_LANES_VR8		8
 #define __LINK_MODE_LANES_DR8_2		8
+#define __LINK_MODE_LANES_T1BRR		1
 
 #define __DEFINE_LINK_MODE_PARAMS(_speed, _type, _duplex)	\
 	[ETHTOOL_LINK_MODE(_speed, _type, _duplex)] = {		\
@@ -374,6 +376,7 @@ const struct link_mode_info link_mode_params[] = {
 	__DEFINE_LINK_MODE_PARAMS(10, T1S, Full),
 	__DEFINE_LINK_MODE_PARAMS(10, T1S, Half),
 	__DEFINE_LINK_MODE_PARAMS(10, T1S_P2MP, Half),
+	__DEFINE_LINK_MODE_PARAMS(10, T1BRR, Full),
 };
 static_assert(ARRAY_SIZE(link_mode_params) == __ETHTOOL_LINK_MODE_MASK_NBITS);
 
-- 
2.39.2

Re: [PATCH v5 1/3] net: phy: bcm54811: New link mode for BroadR-Reach

[Andrew Lunn]

On Wed, Jun 05, 2024 at 11:56:44AM +0200, Kamil Horák - 2N wrote:
> Introduce a new link mode necessary for 10 MBit single-pair
> connection in BroadR-Reach mode on bcm5481x PHY by Broadcom.
> This new link mode, 10baseT1BRR, is known as 1BR10 in the Broadcom
> terminology. Another link mode to be used is 1BR100 and it is already
> present as 100baseT1, because Broadcom's 1BR100 became 100baseT1
> (IEEE 802.3bw).
> 
> Signed-off-by: Kamil Horák - 2N <kamilh@axis.com>

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

    Andrew

[PATCH v5 2/3] net: phy: bcm54811: Add LRE registers definitions

[Kamil Horák - 2N]

Add the definitions of LRE registers for Broadcom BCM5481x PHY

Signed-off-by: Kamil Horák - 2N <kamilh@axis.com>
---
 include/linux/brcmphy.h | 80 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)

diff --git a/include/linux/brcmphy.h b/include/linux/brcmphy.h
index 1394ba302367..1b02e1014583 100644
--- a/include/linux/brcmphy.h
+++ b/include/linux/brcmphy.h
@@ -270,6 +270,86 @@
 #define BCM5482_SSD_SGMII_SLAVE		0x15	/* SGMII Slave Register */
 #define BCM5482_SSD_SGMII_SLAVE_EN	0x0002	/* Slave mode enable */
 #define BCM5482_SSD_SGMII_SLAVE_AD	0x0001	/* Slave auto-detection */
+#define BCM5482_SSD_SGMII_SLAVE_AD	0x0001	/* Slave auto-detection */
+
+/* BroadR-Reach LRE Registers. */
+#define MII_BCM54XX_LRECR		0x00	/* LRE Control Register                    */
+#define MII_BCM54XX_LRESR		0x01	/* LRE Status Register                     */
+#define MII_BCM54XX_LREPHYSID1		0x02	/* LRE PHYS ID 1                           */
+#define MII_BCM54XX_LREPHYSID2		0x03	/* LRE PHYS ID 2                           */
+#define MII_BCM54XX_LREANAA		0x04	/* LDS Auto-Negotiation Advertised Ability */
+#define MII_BCM54XX_LREANAC		0x05	/* LDS Auto-Negotiation Advertised Control */
+#define MII_BCM54XX_LREANPT		0x06	/* LDS Ability Next Page Transmit          */
+#define MII_BCM54XX_LRELPA		0x07	/* LDS Link Partner Ability                */
+#define MII_BCM54XX_LRELPNPM		0x08	/* LDS Link Partner Next Page Message      */
+#define MII_BCM54XX_LRELPNPC		0x09	/* LDS Link Partner Next Page Control      */
+#define MII_BCM54XX_LRELDSE		0x0a	/* LDS Expansion Register                  */
+#define MII_BCM54XX_LREES		0x0f	/* LRE Extended Status                     */
+
+/* LRE control register. */
+#define LRECR_RESET			0x8000	/* Reset to default state      */
+#define LRECR_LOOPBACK			0x4000	/* Internal Loopback           */
+#define LRECR_LDSRES			0x2000	/* Restart LDS Process         */
+#define LRECR_LDSEN			0x1000	/* LDS Enable                  */
+#define LRECR_PDOWN			0x0800	/* Enable low power state      */
+#define LRECR_ISOLATE			0x0400	/* Isolate data paths from MII */
+#define LRECR_SPEED100			0x0200	/* Select 100 Mbps             */
+#define LRECR_SPEED10			0x0000	/* Select 10 Mbps              */
+#define LRECR_4PAIRS			0x0020	/* Select 4 Pairs              */
+#define LRECR_2PAIRS			0x0010	/* Select 2 Pairs              */
+#define LRECR_1PAIR			0x0000	/* Select 1 Pair               */
+#define LRECR_MASTER			0x0008	/* Force Master when LDS disabled */
+#define LRECR_SLAVE			0x0000	/* Force Slave when LDS disabled  */
+
+/* LRE status register. */
+#define LRESR_100_1PAIR			0x2000	/* Can do 100Mbps 1 Pair       */
+#define LRESR_100_4PAIR			0x1000	/* Can do 100Mbps 4 Pairs      */
+#define LRESR_100_2PAIR			0x0800	/* Can do 100Mbps 2 Pairs      */
+#define LRESR_10_2PAIR			0x0400	/* Can do 10Mbps 2 Pairs       */
+#define LRESR_10_1PAIR			0x0200	/* Can do 10Mbps 1 Pair        */
+#define LRESR_ESTATEN			0x0100	/* Extended Status in R15      */
+#define LRESR_RESV			0x0080	/* Unused...                   */
+#define LRESR_MFPS			0x0040	/* Can suppress Management Frames Preamble */
+#define LRESR_LDSCOMPLETE		0x0020	/* LDS Auto-negotiation complete */
+#define LRESR_8023			0x0010	/* Has IEEE 802.3 Support      */
+#define LRESR_LDSABILITY		0x0008	/* LDS auto-negotiation capable */
+#define LRESR_LSTATUS			0x0004	/* Link status                 */
+#define LRESR_JCD			0x0002	/* Jabber detected             */
+#define LRESR_ERCAP			0x0001	/* Ext-reg capability          */
+
+/* LDS Auto-Negotiation Advertised Ability. */
+#define LREANAA_PAUSE_ASYM		0x8000	/* Can pause asymmetrically    */
+#define LREANAA_PAUSE			0x4000	/* Can pause                   */
+#define LREANAA_100_1PAIR		0x0020	/* Can do 100Mbps 1 Pair       */
+#define LREANAA_100_4PAIR		0x0010	/* Can do 100Mbps 4 Pair       */
+#define LREANAA_100_2PAIR		0x0008	/* Can do 100Mbps 2 Pair       */
+#define LREANAA_10_2PAIR		0x0004	/* Can do 10Mbps 2 Pair        */
+#define LREANAA_10_1PAIR		0x0002	/* Can do 10Mbps 1 Pair        */
+
+#define LRE_ADVERTISE_FULL		(LREANAA_100_1PAIR | LREANAA_100_4PAIR | \
+					 LREANAA_100_2PAIR | LREANAA_10_2PAIR | \
+					 LREANAA_10_1PAIR)
+
+#define LRE_ADVERTISE_ALL		LRE_ADVERTISE_FULL
+
+/* LDS Link Partner Ability. */
+#define LRELPA_PAUSE_ASYM		0x8000	/* Supports asymmetric pause   */
+#define LRELPA_PAUSE			0x4000	/* Supports pause capability   */
+#define LRELPA_100_1PAIR		0x0020	/* 100Mbps 1 Pair capable      */
+#define LRELPA_100_4PAIR		0x0010	/* 100Mbps 4 Pair capable      */
+#define LRELPA_100_2PAIR		0x0008	/* 100Mbps 2 Pair capable      */
+#define LRELPA_10_2PAIR			0x0004	/* 10Mbps 2 Pair capable       */
+#define LRELPA_10_1PAIR			0x0002	/* 10Mbps 1 Pair capable       */
+
+/* LDS Expansion register. */
+#define LDSE_DOWNGRADE			0x8000	/* Can do LDS Speed Downgrade  */
+#define LDSE_MASTER			0x4000	/* Master / Slave              */
+#define LDSE_PAIRS_MASK			0x3000	/* Pair Count Mask             */
+#define LDSE_PAIRS_SHIFT		12
+#define LDSE_4PAIRS			(2 << LDSE_PAIRS_SHIFT)	/* 4 Pairs Connection */
+#define LDSE_2PAIRS			(1 << LDSE_PAIRS_SHIFT)	/* 2 Pairs Connection */
+#define LDSE_1PAIR			(0 << LDSE_PAIRS_SHIFT)	/* 1 Pair  Connection */
+#define LDSE_CABLEN_MASK		0x0FFF	/* Cable Length Mask           */
 
 /* BCM54810 Registers */
 #define BCM54810_EXP_BROADREACH_LRE_MISC_CTL	(MII_BCM54XX_EXP_SEL_ER + 0x90)
-- 
2.39.2

[PATCH v5 3/3] net: phy: bcm-phy-lib: Implement BroadR-Reach link modes

[Kamil Horák - 2N]

Implement single-pair BroadR-Reach modes on bcm5481x PHY by Broadcom.
Create set of functions alternative to IEEE 802.3 to handle configuration
of these modes on compatible Broadcom PHYs.

Change-Id: I592d261bc0d60aaa78fc1717a315b0b1c1449c81
Signed-off-by: Kamil Horák - 2N <kamilh@axis.com>
---
 drivers/net/phy/bcm-phy-lib.c | 123 ++++++++++++
 drivers/net/phy/bcm-phy-lib.h |   4 +
 drivers/net/phy/broadcom.c    | 368 ++++++++++++++++++++++++++++++++--
 drivers/net/phy/phy-core.c    |   2 +-
 include/linux/brcmphy.h       |   9 +
 5 files changed, 488 insertions(+), 18 deletions(-)

diff --git a/drivers/net/phy/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c
index 876f28fd8256..cc1b5e5a958c 100644
--- a/drivers/net/phy/bcm-phy-lib.c
+++ b/drivers/net/phy/bcm-phy-lib.c
@@ -794,6 +794,47 @@ static int _bcm_phy_cable_test_get_status(struct phy_device *phydev,
 	return ret;
 }
 
+static int bcm_setup_forced(struct phy_device *phydev)
+{
+	u16 ctl = 0;
+
+	phydev->pause = 0;
+	phydev->asym_pause = 0;
+
+	if (phydev->speed == SPEED_100)
+		ctl |= LRECR_SPEED100;
+
+	if (phydev->duplex != DUPLEX_FULL)
+		return -EOPNOTSUPP;
+
+	return phy_modify(phydev, MII_BCM54XX_LRECR, LRECR_SPEED100, ctl);
+}
+
+/**
+ * bcm_linkmode_adv_to_mii_adv_t
+ * @advertising: the linkmode advertisement settings
+ * @return: LDS Auto-Negotiation Advertised Ability register value
+ *
+ * A small helper function that translates linkmode advertisement
+ * settings to phy autonegotiation advertisements for the
+ * MII_BCM54XX_LREANAA register of Broadcom PHYs capable of LDS
+ */
+static u32 bcm_linkmode_adv_to_mii_adv_t(unsigned long *advertising)
+{
+	u32 result = 0;
+
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT, advertising))
+		result |= LREANAA_10_1PAIR;
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_100baseT1_Full_BIT, advertising))
+		result |= LREANAA_100_1PAIR;
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT, advertising))
+		result |= LRELPA_PAUSE;
+	if (linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, advertising))
+		result |= LRELPA_PAUSE_ASYM;
+
+	return result;
+}
+
 int bcm_phy_cable_test_start(struct phy_device *phydev)
 {
 	return _bcm_phy_cable_test_start(phydev, false);
@@ -1066,6 +1107,88 @@ int bcm_phy_led_brightness_set(struct phy_device *phydev,
 }
 EXPORT_SYMBOL_GPL(bcm_phy_led_brightness_set);
 
+int bcm_setup_master_slave(struct phy_device *phydev)
+{
+	u16 ctl = 0;
+
+	switch (phydev->master_slave_set) {
+	case MASTER_SLAVE_CFG_MASTER_PREFERRED:
+	case MASTER_SLAVE_CFG_MASTER_FORCE:
+		ctl = LRECR_MASTER;
+		break;
+	case MASTER_SLAVE_CFG_SLAVE_PREFERRED:
+	case MASTER_SLAVE_CFG_SLAVE_FORCE:
+		break;
+	case MASTER_SLAVE_CFG_UNKNOWN:
+	case MASTER_SLAVE_CFG_UNSUPPORTED:
+		return 0;
+	default:
+		phydev_warn(phydev, "Unsupported Master/Slave mode\n");
+		return -EOPNOTSUPP;
+	}
+
+	return phy_modify_changed(phydev, MII_BCM54XX_LRECR, LRECR_MASTER, ctl);
+}
+EXPORT_SYMBOL_GPL(bcm_setup_master_slave);
+
+int bcm_config_aneg(struct phy_device *phydev, bool changed)
+{
+	int err;
+
+	if (genphy_config_eee_advert(phydev))
+		changed = true;
+
+	err = bcm_setup_master_slave(phydev);
+	if (err < 0)
+		return err;
+	else if (err)
+		changed = true;
+
+	if (phydev->autoneg != AUTONEG_ENABLE)
+		return bcm_setup_forced(phydev);
+
+	err = bcm_config_advert(phydev);
+	if (err < 0)
+		return err;
+	else if (err)
+		changed = true;
+
+	return genphy_check_and_restart_aneg(phydev, changed);
+}
+EXPORT_SYMBOL_GPL(bcm_config_aneg);
+
+/**
+ * bcm_config_advert - sanitize and advertise auto-negotiation parameters
+ * @phydev: target phy_device struct
+ *
+ * Description: Writes MII_BCM54XX_LREANAA with the appropriate values,
+ *   after sanitizing the values to make sure we only advertise
+ *   what is supported.  Returns < 0 on error, 0 if the PHY's advertisement
+ *   hasn't changed, and > 0 if it has changed.
+ */
+int bcm_config_advert(struct phy_device *phydev)
+{
+	int err;
+	u32 adv;
+
+	/* Only allow advertising what this PHY supports */
+	linkmode_and(phydev->advertising, phydev->advertising,
+		     phydev->supported);
+
+	adv = bcm_linkmode_adv_to_mii_adv_t(phydev->advertising);
+
+	/* Setup BroadR-Reach mode advertisement */
+	err = phy_modify_changed(phydev, MII_BCM54XX_LREANAA,
+				 LRE_ADVERTISE_ALL | LREANAA_PAUSE |
+				 LREANAA_PAUSE_ASYM, adv);
+
+	if (err < 0)
+		return err;
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(bcm_config_advert);
+
 MODULE_DESCRIPTION("Broadcom PHY Library");
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Broadcom Corporation");
diff --git a/drivers/net/phy/bcm-phy-lib.h b/drivers/net/phy/bcm-phy-lib.h
index b52189e45a84..0f6d06c0b7af 100644
--- a/drivers/net/phy/bcm-phy-lib.h
+++ b/drivers/net/phy/bcm-phy-lib.h
@@ -121,4 +121,8 @@ irqreturn_t bcm_phy_wol_isr(int irq, void *dev_id);
 int bcm_phy_led_brightness_set(struct phy_device *phydev,
 			       u8 index, enum led_brightness value);
 
+int bcm_setup_master_slave(struct phy_device *phydev);
+int bcm_config_aneg(struct phy_device *phydev, bool changed);
+int bcm_config_advert(struct phy_device *phydev);
+
 #endif /* _LINUX_BCM_PHY_LIB_H */
diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
index 370e4ed45098..5eaad9913df6 100644
--- a/drivers/net/phy/broadcom.c
+++ b/drivers/net/phy/broadcom.c
@@ -553,18 +553,98 @@ static int bcm54810_write_mmd(struct phy_device *phydev, int devnum, u16 regnum,
 	return -EOPNOTSUPP;
 }
 
-static int bcm54811_config_init(struct phy_device *phydev)
+static int bcm5481x_get_brrmode(struct phy_device *phydev, u8 *data)
 {
-	int err, reg;
+	int reg;
 
-	/* Disable BroadR-Reach function. */
 	reg = bcm_phy_read_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL);
-	reg &= ~BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN;
-	err = bcm_phy_write_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL,
-				reg);
-	if (err < 0)
+
+	*data = (reg & BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN) ? 1 : 0;
+
+	return 0;
+}
+
+static int bcm54811_read_abilities(struct phy_device *phydev)
+{
+	int val, err;
+	int i;
+	u8 brr_mode;
+	static const int modes_array[] = { ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
+					   ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT,
+					   ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
+					   ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
+					   ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
+					   ETHTOOL_LINK_MODE_100baseT_Full_BIT,
+					   ETHTOOL_LINK_MODE_100baseT_Half_BIT,
+					   ETHTOOL_LINK_MODE_10baseT_Full_BIT,
+					   ETHTOOL_LINK_MODE_10baseT_Half_BIT };
+
+	for (i = 0; i < ARRAY_SIZE(modes_array); i++)
+		linkmode_clear_bit(modes_array[i], phydev->supported);
+
+	err = bcm5481x_get_brrmode(phydev, &brr_mode);
+	if (err)
+		return err;
+
+	if (brr_mode) {
+		linkmode_set_bit_array(phy_basic_ports_array,
+				       ARRAY_SIZE(phy_basic_ports_array),
+				       phydev->supported);
+
+		val = phy_read(phydev, MII_BCM54XX_LRESR);
+		if (val < 0)
+			return val;
+
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_Autoneg_BIT,
+				 phydev->supported, 1);
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
+				 phydev->supported,
+				 val & LRESR_100_1PAIR);
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT,
+				 phydev->supported,
+				 val & LRESR_10_1PAIR);
+	} else {
+		return genphy_read_abilities(phydev);
+	}
+
+	return 0;
+}
+
+static int bcm5481x_set_brrmode(struct phy_device *phydev, bool on)
+{
+	int reg;
+	int err;
+
+	reg = bcm_phy_read_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL);
+
+	if (on)
+		reg |= BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN;
+	else
+		reg &= ~BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN;
+
+	err = bcm_phy_write_exp(phydev, BCM54810_EXP_BROADREACH_LRE_MISC_CTL, reg);
+	if (err)
+		return err;
+
+	/* Update the abilities based on the current brr on/off setting */
+	err = bcm54811_read_abilities(phydev);
+	if (err)
 		return err;
 
+	/* Ensure LRE or IEEE register set is accessed according to the brr on/off,
+	 *  thus set the override
+	 */
+	return bcm_phy_write_exp(phydev, BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL,
+		BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL_EN |
+		(on ? 0 : BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL_OVERRIDE_VAL));
+}
+
+static int bcm54811_config_init(struct phy_device *phydev)
+{
+	int err, reg;
+	bool brr = false;
+	struct device_node *np = phydev->mdio.dev.of_node;
+
 	err = bcm54xx_config_init(phydev);
 
 	/* Enable CLK125 MUX on LED4 if ref clock is enabled. */
@@ -576,29 +656,79 @@ static int bcm54811_config_init(struct phy_device *phydev)
 			return err;
 	}
 
-	return err;
+	/* Configure BroadR-Reach function. */
+	brr = of_property_read_bool(np, "brr-mode");
+
+	/* With BCM54811, BroadR-Reach implies no autoneg */
+	if (brr)
+		phydev->autoneg = 0;
+
+	return bcm5481x_set_brrmode(phydev, brr);
 }
 
-static int bcm5481_config_aneg(struct phy_device *phydev)
+static int bcm5481x_config_delay_swap(struct phy_device *phydev)
 {
 	struct device_node *np = phydev->mdio.dev.of_node;
-	int ret;
 
-	/* Aneg firstly. */
-	ret = genphy_config_aneg(phydev);
-
-	/* Then we can set up the delay. */
+	/* Set up the delay. */
 	bcm54xx_config_clock_delay(phydev);
 
 	if (of_property_read_bool(np, "enet-phy-lane-swap")) {
 		/* Lane Swap - Undocumented register...magic! */
-		ret = bcm_phy_write_exp(phydev, MII_BCM54XX_EXP_SEL_ER + 0x9,
+		int ret = bcm_phy_write_exp(phydev, MII_BCM54XX_EXP_SEL_ER + 0x9,
 					0x11B);
 		if (ret < 0)
 			return ret;
 	}
 
-	return ret;
+	return 0;
+}
+
+static int bcm5481_config_aneg(struct phy_device *phydev)
+{
+	int ret;
+	u8 brr_mode;
+
+	/* Aneg firstly. */
+	ret = bcm5481x_get_brrmode(phydev, &brr_mode);
+	if (ret)
+		return ret;
+
+	if (brr_mode)
+		ret = bcm_config_aneg(phydev, false);
+	else
+		ret = genphy_config_aneg(phydev);
+
+	if (ret)
+		return ret;
+
+	/* Then we can set up the delay and swap. */
+	return bcm5481x_config_delay_swap(phydev);
+}
+
+static int bcm54811_config_aneg(struct phy_device *phydev)
+{
+	int ret;
+	u8 brr_mode;
+
+	/* Aneg firstly. */
+	ret = bcm5481x_get_brrmode(phydev, &brr_mode);
+	if (ret)
+		return ret;
+
+	if (brr_mode) {
+		/* BCM54811 is only capable of autonegotiation in IEEE mode */
+		phydev->autoneg = 0;
+		ret = bcm_config_aneg(phydev, false);
+	} else {
+		ret = genphy_config_aneg(phydev);
+	}
+
+	if (ret)
+		return ret;
+
+	/* Then we can set up the delay and swap. */
+	return bcm5481x_config_delay_swap(phydev);
 }
 
 struct bcm54616s_phy_priv {
@@ -1062,6 +1192,208 @@ static void bcm54xx_link_change_notify(struct phy_device *phydev)
 	bcm_phy_write_exp(phydev, MII_BCM54XX_EXP_EXP08, ret);
 }
 
+static int bcm_read_master_slave(struct phy_device *phydev)
+{
+	int cfg = MASTER_SLAVE_CFG_UNKNOWN, state;
+	int val;
+
+	/* In BroadR-Reach mode we are always capable of master-slave
+	 *  and there is no preferred master or slave configuration
+	 */
+	phydev->master_slave_get = MASTER_SLAVE_CFG_UNKNOWN;
+	phydev->master_slave_state = MASTER_SLAVE_STATE_UNKNOWN;
+
+	val = phy_read(phydev, MII_BCM54XX_LRECR);
+	if (val < 0)
+		return val;
+
+	if ((val & LRECR_LDSEN) == 0) {
+		if (val & LRECR_MASTER)
+			cfg = MASTER_SLAVE_CFG_MASTER_FORCE;
+		else
+			cfg = MASTER_SLAVE_CFG_SLAVE_FORCE;
+	}
+
+	val = phy_read(phydev, MII_BCM54XX_LRELDSE);
+	if (val < 0)
+		return val;
+
+	if (val & LDSE_MASTER)
+		state = MASTER_SLAVE_STATE_MASTER;
+	else
+		state = MASTER_SLAVE_STATE_SLAVE;
+
+	phydev->master_slave_get = cfg;
+	phydev->master_slave_state = state;
+
+	return 0;
+}
+
+/* Read LDS Link Partner Ability in BroadR-Reach mode */
+static int bcm_read_lpa(struct phy_device *phydev)
+{
+	int i, lrelpa;
+
+	if (phydev->autoneg != AUTONEG_ENABLE) {
+		if (!phydev->autoneg_complete) {
+			/* aneg not yet done, reset all relevant bits */
+			static const int br_bits[] = { ETHTOOL_LINK_MODE_Autoneg_BIT,
+						       ETHTOOL_LINK_MODE_Pause_BIT,
+						       ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+						       ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT,
+						       ETHTOOL_LINK_MODE_100baseT1_Full_BIT };
+			for (i = 0; i < ARRAY_SIZE(br_bits); i++)
+				linkmode_clear_bit(br_bits[i], phydev->lp_advertising);
+
+			return 0;
+		}
+
+		/* Long-Distance Signaling Link Partner Ability */
+		lrelpa = phy_read(phydev, MII_BCM54XX_LRELPA);
+		if (lrelpa < 0)
+			return lrelpa;
+
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+				 phydev->lp_advertising, lrelpa & LRELPA_PAUSE_ASYM);
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+				 phydev->lp_advertising, lrelpa & LRELPA_PAUSE);
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
+				 phydev->lp_advertising, lrelpa & LRELPA_100_1PAIR);
+		linkmode_mod_bit(ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT,
+				 phydev->lp_advertising, lrelpa & LRELPA_10_1PAIR);
+	} else {
+		linkmode_zero(phydev->lp_advertising);
+	}
+
+	return 0;
+}
+
+static int bcm_read_status_fixed(struct phy_device *phydev)
+{
+	int lrecr = phy_read(phydev, MII_BCM54XX_LRECR);
+
+	if (lrecr < 0)
+		return lrecr;
+
+	phydev->duplex = DUPLEX_FULL;
+
+	if (lrecr & LRECR_SPEED100)
+		phydev->speed = SPEED_100;
+	else
+		phydev->speed = SPEED_10;
+
+	return 0;
+}
+
+/**
+ * lre_update_link - update link status in @phydev
+ * @phydev: target phy_device struct
+ *
+ * Description: Update the value in phydev->link to reflect the
+ *   current link value.  In order to do this, we need to read
+ *   the status register twice, keeping the second value.
+ *   This is a genphy_update_link modified to work on LRE registers
+ *   of BroadR-Reach PHY
+ */
+static int lre_update_link(struct phy_device *phydev)
+{
+	int status = 0, lrecr;
+
+	lrecr = phy_read(phydev, MII_BCM54XX_LRECR);
+	if (lrecr < 0)
+		return lrecr;
+
+	/* Autoneg is being started, therefore disregard BMSR value and
+	 * report link as down.
+	 */
+	if (lrecr & BMCR_ANRESTART)
+		goto done;
+
+	/* The link state is latched low so that momentary link
+	 * drops can be detected. Do not double-read the status
+	 * in polling mode to detect such short link drops except
+	 * the link was already down.
+	 */
+	if (!phy_polling_mode(phydev) || !phydev->link) {
+		status = phy_read(phydev, MII_BCM54XX_LRESR);
+		if (status < 0)
+			return status;
+		else if (status & LRESR_LSTATUS)
+			goto done;
+	}
+
+	/* Read link and autonegotiation status */
+	status = phy_read(phydev, MII_BCM54XX_LRESR);
+	if (status < 0)
+		return status;
+done:
+	phydev->link = status & LRESR_LSTATUS ? 1 : 0;
+	phydev->autoneg_complete = status & LRESR_LDSCOMPLETE ? 1 : 0;
+
+	/* Consider the case that autoneg was started and "aneg complete"
+	 * bit has been reset, but "link up" bit not yet.
+	 */
+	if (phydev->autoneg == AUTONEG_ENABLE && !phydev->autoneg_complete)
+		phydev->link = 0;
+
+	return 0;
+}
+
+static int bcm54811_read_status(struct phy_device *phydev)
+{
+	int err;
+	u8 brr_mode;
+
+	err = bcm5481x_get_brrmode(phydev, &brr_mode);
+
+	if (err)
+		return err;
+
+	if (brr_mode) {
+		/* Get the status in BroadRReach mode just like genphy_read_status
+		 *   does in normal mode
+		 */
+
+		int err, old_link = phydev->link;
+
+		/* Update the link, but return if there was an error */
+
+		err = lre_update_link(phydev);
+		if (err)
+			return err;
+
+		/* why bother the PHY if nothing can have changed */
+		if (phydev->autoneg == AUTONEG_ENABLE && old_link && phydev->link)
+			return 0;
+
+		phydev->speed = SPEED_UNKNOWN;
+		phydev->duplex = DUPLEX_UNKNOWN;
+		phydev->pause = 0;
+		phydev->asym_pause = 0;
+
+		err = bcm_read_master_slave(phydev);
+		if (err < 0)
+			return err;
+
+		/* Read LDS Link Partner Ability */
+		err = bcm_read_lpa(phydev);
+		if (err < 0)
+			return err;
+
+		if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete) {
+			phy_resolve_aneg_linkmode(phydev);
+		} else if (phydev->autoneg == AUTONEG_DISABLE) {
+			err = bcm_read_status_fixed(phydev);
+			if (err < 0)
+				return err;
+		}
+	} else {
+		err = genphy_read_status(phydev);
+	}
+
+	return err;
+}
+
 static struct phy_driver broadcom_drivers[] = {
 {
 	.phy_id		= PHY_ID_BCM5411,
@@ -1212,9 +1544,11 @@ static struct phy_driver broadcom_drivers[] = {
 	.get_stats	= bcm54xx_get_stats,
 	.probe		= bcm54xx_phy_probe,
 	.config_init    = bcm54811_config_init,
-	.config_aneg    = bcm5481_config_aneg,
+	.config_aneg    = bcm54811_config_aneg,
 	.config_intr    = bcm_phy_config_intr,
 	.handle_interrupt = bcm_phy_handle_interrupt,
+	.read_status	= bcm54811_read_status,
+	.get_features	= bcm54811_read_abilities,
 	.suspend	= bcm54xx_suspend,
 	.resume		= bcm54xx_resume,
 	.link_change_notify	= bcm54xx_link_change_notify,
diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c
index 4a1972e94107..3e683a890a46 100644
--- a/drivers/net/phy/phy-core.c
+++ b/drivers/net/phy/phy-core.c
@@ -13,7 +13,7 @@
  */
 const char *phy_speed_to_str(int speed)
 {
-	BUILD_BUG_ON_MSG(__ETHTOOL_LINK_MODE_MASK_NBITS != 102,
+	BUILD_BUG_ON_MSG(__ETHTOOL_LINK_MODE_MASK_NBITS != 103,
 		"Enum ethtool_link_mode_bit_indices and phylib are out of sync. "
 		"If a speed or mode has been added please update phy_speed_to_str "
 		"and the PHY settings array.\n");
diff --git a/include/linux/brcmphy.h b/include/linux/brcmphy.h
index 1b02e1014583..ae39c33e4086 100644
--- a/include/linux/brcmphy.h
+++ b/include/linux/brcmphy.h
@@ -357,6 +357,15 @@
 #define BCM54810_SHD_CLK_CTL			0x3
 #define BCM54810_SHD_CLK_CTL_GTXCLK_EN		(1 << 9)
 
+/* BCM54811 Registers */
+#define BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL	(MII_BCM54XX_EXP_SEL_ER + 0x9A)
+/* Access Control Override Enable */
+#define BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL_EN		BIT(15)
+/* Access Control Override Value */
+#define BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL_OVERRIDE_VAL	BIT(14)
+/* Access Control Value */
+#define BCM54811_EXP_BROADREACH_LRE_OVERLAY_CTL_VAL		BIT(13)
+
 /* BCM54612E Registers */
 #define BCM54612E_EXP_SPARE0		(MII_BCM54XX_EXP_SEL_ETC + 0x34)
 #define BCM54612E_LED4_CLK125OUT_EN	(1 << 1)
-- 
2.39.2

Re: [PATCH v5 3/3] net: phy: bcm-phy-lib: Implement BroadR-Reach link modes

[Andrew Lunn]

On Wed, Jun 05, 2024 at 11:56:46AM +0200, Kamil Horák - 2N wrote:
> Implement single-pair BroadR-Reach modes on bcm5481x PHY by Broadcom.
> Create set of functions alternative to IEEE 802.3 to handle configuration
> of these modes on compatible Broadcom PHYs.
> 
> Change-Id: I592d261bc0d60aaa78fc1717a315b0b1c1449c81
> Signed-off-by: Kamil Horák - 2N <kamilh@axis.com>
> ---
>  drivers/net/phy/bcm-phy-lib.c | 123 ++++++++++++
>  drivers/net/phy/bcm-phy-lib.h |   4 +
>  drivers/net/phy/broadcom.c    | 368 ++++++++++++++++++++++++++++++++--
>  drivers/net/phy/phy-core.c    |   2 +-
>  include/linux/brcmphy.h       |   9 +
>  5 files changed, 488 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/net/phy/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c
> index 876f28fd8256..cc1b5e5a958c 100644
> --- a/drivers/net/phy/bcm-phy-lib.c
> +++ b/drivers/net/phy/bcm-phy-lib.c
> @@ -794,6 +794,47 @@ static int _bcm_phy_cable_test_get_status(struct phy_device *phydev,
>  	return ret;
>  }
>  
> +static int bcm_setup_forced(struct phy_device *phydev)
> +{
> +	u16 ctl = 0;
> +
> +	phydev->pause = 0;
> +	phydev->asym_pause = 0;
> +
> +	if (phydev->speed == SPEED_100)
> +		ctl |= LRECR_SPEED100;
> +
> +	if (phydev->duplex != DUPLEX_FULL)
> +		return -EOPNOTSUPP;
> +
> +	return phy_modify(phydev, MII_BCM54XX_LRECR, LRECR_SPEED100, ctl);

We should consider naming here. I assume this will not work for IEEE
forced mode? So maybe this should have _lre_ or _brr_ in the name to
make it clear what it actually does.

> +}



> +
> +/**
> + * bcm_linkmode_adv_to_mii_adv_t
> + * @advertising: the linkmode advertisement settings
> + * @return: LDS Auto-Negotiation Advertised Ability register value
> + *
> + * A small helper function that translates linkmode advertisement
> + * settings to phy autonegotiation advertisements for the
> + * MII_BCM54XX_LREANAA register of Broadcom PHYs capable of LDS
> + */
> +static u32 bcm_linkmode_adv_to_mii_adv_t(unsigned long *advertising)
> +{
> +	u32 result = 0;

Make here, and maybe lre_advertising?

Please go through all the functions and think about naming.

    Andrew

---
pw-bot: cr

Re: [PATCH v5 3/3] net: phy: bcm-phy-lib: Implement BroadR-Reach link modes

[Simon Horman]

On Wed, Jun 05, 2024 at 11:56:46AM +0200, Kamil Horák - 2N wrote:
> Implement single-pair BroadR-Reach modes on bcm5481x PHY by Broadcom.
> Create set of functions alternative to IEEE 802.3 to handle configuration
> of these modes on compatible Broadcom PHYs.
> 
> Change-Id: I592d261bc0d60aaa78fc1717a315b0b1c1449c81

Hi Kamil,

Please don't include tags for external trackers in upstream commit messages.

> Signed-off-by: Kamil Horák - 2N <kamilh@axis.com>

...

> diff --git a/drivers/net/phy/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c

...

> +/**
> + * bcm_linkmode_adv_to_mii_adv_t

Please include a short description on the line above.

Flagged by kernel-doc -none -Wall

> + * @advertising: the linkmode advertisement settings
> + * @return: LDS Auto-Negotiation Advertised Ability register value
> + *
> + * A small helper function that translates linkmode advertisement
> + * settings to phy autonegotiation advertisements for the
> + * MII_BCM54XX_LREANAA register of Broadcom PHYs capable of LDS
> + */
> +static u32 bcm_linkmode_adv_to_mii_adv_t(unsigned long *advertising)

...

> +/**
> + * bcm_config_advert - sanitize and advertise auto-negotiation parameters
> + * @phydev: target phy_device struct
> + *
> + * Description: Writes MII_BCM54XX_LREANAA with the appropriate values,
> + *   after sanitizing the values to make sure we only advertise
> + *   what is supported.  Returns < 0 on error, 0 if the PHY's advertisement
> + *   hasn't changed, and > 0 if it has changed.
> + */
> +int bcm_config_advert(struct phy_device *phydev)

Please consider including a Return: section in Kernel docs
for functions that return a value. Likewise for lre_update_link.

Also flagged by kernel-doc -none -Wall

...

> diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c

...

> +static int bcm54811_read_abilities(struct phy_device *phydev)
> +{
> +	int val, err;
> +	int i;
> +	u8 brr_mode;
> +	static const int modes_array[] = { ETHTOOL_LINK_MODE_100baseT1_Full_BIT,
> +					   ETHTOOL_LINK_MODE_10baseT1BRR_Full_BIT,
> +					   ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
> +					   ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
> +					   ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
> +					   ETHTOOL_LINK_MODE_100baseT_Full_BIT,
> +					   ETHTOOL_LINK_MODE_100baseT_Half_BIT,
> +					   ETHTOOL_LINK_MODE_10baseT_Full_BIT,
> +					   ETHTOOL_LINK_MODE_10baseT_Half_BIT };

Please consider arranging local variables in reverse xmas tree order -
longest like to shortest.

Edward Cree's tool can be useful here:
https://github.com/ecree-solarflare/xmastree

...