2024-04-16 12:39:14

by Kamil Horák - 2N

[permalink] [raw]
Subject: [PATCH] net: phy: bcm54811: add support for BroadR-Reach mode

Enable the BroadR-Reach link modes for BCM54811 PHY by Broadcom.
This allows for two-wire Ethernet at 10 or 100MBit using BroadR-Reach
mode and also for other BroadR-Reach modes using more than one pair.

Signed-off-by: Kamil Horák - 2N <[email protected]>
---
drivers/net/phy/broadcom.c | 432 ++++++++++++++++++++++++++++++++++-
drivers/net/phy/phy-core.c | 13 +-
include/linux/brcmphy.h | 91 +++++++-
include/uapi/linux/ethtool.h | 13 +-
net/ethtool/common.c | 31 +++
net/ethtool/ioctl.c | 1 +
net/ipv4/tcp.c | 2 +-
7 files changed, 567 insertions(+), 16 deletions(-)

diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
index 370e4ed45098..aeb49b566aca 100644
--- a/drivers/net/phy/broadcom.c
+++ b/drivers/net/phy/broadcom.c
@@ -553,18 +553,46 @@ 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 bcm54811_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) ?
+ ETHTOOL_PHY_BRR_MODE_ON : ETHTOOL_PHY_BRR_MODE_OFF;
+
+ return 0;
+}
+
+static int bcm54811_set_brrmode(struct phy_device *phydev, u8 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;

+ /* 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;
+
err = bcm54xx_config_init(phydev);

/* Enable CLK125 MUX on LED4 if ref clock is enabled. */
@@ -576,16 +604,151 @@ static int bcm54811_config_init(struct phy_device *phydev)
return err;
}

- return err;
+ /* Configure BroadR-Reach function. */
+ return bcm54811_set_brrmode(phydev, ETHTOOL_PHY_BRR_MODE_OFF);
+}
+
+static 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:
+ break;
+ 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);
+}
+
+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
+ *
+ * A small helper function that translates linkmode advertisement
+ * settings to phy autonegotiation advertisements for the
+ * MII_BCM54XX_LREANAA register.
+ */
+static inline u32 bcm_linkmode_adv_to_mii_adv_t(unsigned long *advertising)
+{
+ u32 result = 0;
+
+ if (linkmode_test_bit(ETHTOOL_LINK_MODE_1BR10_BIT, advertising))
+ result |= LREANAA_10_1PAIR;
+ if (linkmode_test_bit(ETHTOOL_LINK_MODE_2BR10_BIT, advertising))
+ result |= LREANAA_10_2PAIR;
+ if (linkmode_test_bit(ETHTOOL_LINK_MODE_1BR100_BIT, advertising))
+ result |= LREANAA_100_1PAIR;
+ if (linkmode_test_bit(ETHTOOL_LINK_MODE_2BR100_BIT, advertising))
+ result |= LREANAA_100_2PAIR;
+ if (linkmode_test_bit(ETHTOOL_LINK_MODE_4BR100_BIT, advertising))
+ result |= LREANAA_100_4PAIR;
+ 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;
+}
+
+/**
+ * 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.
+ */
+static 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 > 0 ? 1 : 0;
+}
+
+static 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) /* error */
+ return err;
+ else if (err)
+ changed = true;
+
+ return genphy_check_and_restart_aneg(phydev, changed);
}

static int bcm5481_config_aneg(struct phy_device *phydev)
{
struct device_node *np = phydev->mdio.dev.of_node;
int ret;
+ u8 brr_mode;

/* Aneg firstly. */
- ret = genphy_config_aneg(phydev);
+ ret = bcm54811_get_brrmode(phydev, &brr_mode);
+ if (ret)
+ return ret;
+
+ if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON)
+ ret = bcm_config_aneg(phydev, false);
+ else
+ ret = genphy_config_aneg(phydev);

/* Then we can set up the delay. */
bcm54xx_config_clock_delay(phydev);
@@ -1062,6 +1225,253 @@ static void bcm54xx_link_change_notify(struct phy_device *phydev)
bcm_phy_write_exp(phydev, MII_BCM54XX_EXP_EXP08, ret);
}

+static int bcm54811_read_abilities(struct phy_device *phydev)
+{
+ int val, err;
+ int i;
+ static const int modes_array[] = {ETHTOOL_LINK_MODE_1BR100_BIT,
+ ETHTOOL_LINK_MODE_4BR100_BIT,
+ ETHTOOL_LINK_MODE_2BR100_BIT,
+ ETHTOOL_LINK_MODE_2BR10_BIT,
+ ETHTOOL_LINK_MODE_1BR10_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};
+
+ u8 brr_mode;
+
+ for (i = 0; i < ARRAY_SIZE(modes_array); i++)
+ linkmode_clear_bit(modes_array[i], phydev->supported);
+
+ err = bcm54811_get_brrmode(phydev, &brr_mode);
+
+ if (!err) {
+ if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON) {
+ 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_1BR100_BIT,
+ phydev->supported,
+ val & LRESR_100_1PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_4BR100_BIT,
+ phydev->supported,
+ val & LRESR_100_4PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_2BR100_BIT,
+ phydev->supported,
+ val & LRESR_100_2PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_2BR10_BIT,
+ phydev->supported,
+ val & LRESR_10_2PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_1BR10_BIT,
+ phydev->supported,
+ val & LRESR_10_1PAIR);
+ } else {
+ return genphy_read_abilities(phydev);
+ }
+ }
+
+ return err;
+}
+
+static int bcm54811_get_tunable(struct phy_device *phydev,
+ struct ethtool_tunable *tuna, void *data)
+{
+ switch (tuna->id) {
+ case ETHTOOL_PHY_BRR_MODE:
+ return bcm54811_get_brrmode(phydev, data);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int bcm54811_set_tunable(struct phy_device *phydev,
+ struct ethtool_tunable *tuna, const void *data)
+{
+ int res;
+
+ switch (tuna->id) {
+ case ETHTOOL_PHY_BRR_MODE:
+ res = bcm54811_set_brrmode(phydev, *(const u8 *)data);
+ if (res >= 0)
+ res = bcm54811_read_abilities(phydev);
+ break;
+ default:
+ res = -EOPNOTSUPP;
+ }
+
+ return res;
+}
+
+static int bcm_read_master_slave(struct phy_device *phydev)
+{
+ int cfg, 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 int br_bits[] = { ETHTOOL_LINK_MODE_Autoneg_BIT,
+ ETHTOOL_LINK_MODE_Pause_BIT,
+ ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+ ETHTOOL_LINK_MODE_1BR10_BIT,
+ ETHTOOL_LINK_MODE_2BR10_BIT,
+ ETHTOOL_LINK_MODE_1BR100_BIT,
+ ETHTOOL_LINK_MODE_2BR100_BIT,
+ ETHTOOL_LINK_MODE_4BR100_BIT };
+ for (i = 0; i < ARRAY_SIZE(br_bits); i++)
+ linkmode_clear_bit(br_bits[i], phydev->lp_advertising);
+
+ return 0;
+ }
+
+ /* Long-Distance-Signalling 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_1BR100_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_100_1PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_4BR100_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_100_4PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_2BR100_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_100_2PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_2BR10_BIT,
+ phydev->lp_advertising, lrelpa & LRELPA_10_2PAIR);
+ linkmode_mod_bit(ETHTOOL_LINK_MODE_1BR10_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;
+}
+
+static int bcm54811_read_status(struct phy_device *phydev)
+{
+ int err;
+ u8 brr_mode;
+
+ err = bcm54811_get_brrmode(phydev, &brr_mode);
+
+ if (!err) {
+ if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON) {
+ /* 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
+ * genphy_update_link() functions equally on IEEE and LRE
+ * register set
+ */
+
+ err = genphy_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,
@@ -1215,6 +1625,10 @@ static struct phy_driver broadcom_drivers[] = {
.config_aneg = bcm5481_config_aneg,
.config_intr = bcm_phy_config_intr,
.handle_interrupt = bcm_phy_handle_interrupt,
+ .read_status = bcm54811_read_status,
+ .get_tunable = bcm54811_get_tunable,
+ .set_tunable = bcm54811_set_tunable,
+ .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 15f349e5995a..e43baa69ac07 100644
--- a/drivers/net/phy/phy-core.c
+++ b/drivers/net/phy/phy-core.c
@@ -13,10 +13,9 @@
*/
const char *phy_speed_to_str(int speed)
{
- BUILD_BUG_ON_MSG(__ETHTOOL_LINK_MODE_MASK_NBITS != 102,
- "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");
+ BUILD_BUG_ON_MSG(__ETHTOOL_LINK_MODE_MASK_NBITS != 107,
+ "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"
+ );

switch (speed) {
case SPEED_10:
@@ -258,6 +257,9 @@ static const struct phy_setting settings[] = {
PHY_SETTING( 100, HALF, 100baseT_Half ),
PHY_SETTING( 100, HALF, 100baseFX_Half ),
PHY_SETTING( 100, FULL, 100baseFX_Full ),
+ PHY_SETTING( 100, FULL, 4BR100 ),
+ PHY_SETTING( 100, FULL, 2BR100 ),
+ PHY_SETTING( 100, FULL, 1BR100 ),
/* 10M */
PHY_SETTING( 10, FULL, 10baseT_Full ),
PHY_SETTING( 10, HALF, 10baseT_Half ),
@@ -265,6 +267,9 @@ 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, 2BR10 ),
+ PHY_SETTING( 10, FULL, 1BR10 ),
+
};
#undef PHY_SETTING

diff --git a/include/linux/brcmphy.h b/include/linux/brcmphy.h
index 1394ba302367..9c0b78c1b6fb 100644
--- a/include/linux/brcmphy.h
+++ b/include/linux/brcmphy.h
@@ -270,16 +270,105 @@
#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_ERCAP 0x0001 /* Ext-reg capability */
+#define LRESR_JCD 0x0002 /* Jabber detected */
+#define LRESR_LSTATUS 0x0004 /* Link status */
+#define LRESR_LDSABILITY 0x0008 /* Can do LDS */
+#define LRESR_8023 0x0010 /* Has IEEE 802.3 Support */
+#define LRESR_LDSCOMPLETE 0x0020 /* LDS Auto-negotiation complete */
+#define LRESR_MFPS 0x0040 /* Can suppress Management Frames Preamble */
+#define LRESR_RESV 0x0080 /* Unused... */
+#define LRESR_ESTATEN 0x0100 /* Extended Status in R15 */
+#define LRESR_10_1PAIR 0x0200 /* Can do 10Mbps 1 Pair */
+#define LRESR_10_2PAIR 0x0400 /* Can do 10Mbps 2 Pairs */
+#define LRESR_100_2PAIR 0x0800 /* Can do 100Mbps 2 Pairs */
+#define LRESR_100_4PAIR 0x1000 /* Can do 100Mbps 4 Pairs */
+#define LRESR_100_1PAIR 0x2000 /* Can do 100Mbps 1 Pair */
+
+/* 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_4PAIRS 0x2000 /* 4 Pairs Connection */
+#define LDSE_2PAIRS 0x1000 /* 2 Pairs Connection */
+#define LDSE_1PAIR 0x0000 /* 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)
#define BCM54810_EXP_BROADREACH_LRE_MISC_CTL_EN (1 << 0)
#define BCM54810_SHD_CLK_CTL 0x3
#define BCM54810_SHD_CLK_CTL_GTXCLK_EN (1 << 9)
+#define BCM54810_SHD_SCR3_TRDDAPD 0x0100
+
+/* 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)
+#define BCM54612E_LED4_CLK125OUT_EN BIT(1)


/* Wake-on-LAN registers */
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 95c2f09f0d0a..b7389204e715 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -289,11 +289,18 @@ struct ethtool_tunable {
#define ETHTOOL_PHY_EDPD_NO_TX 0xfffe
#define ETHTOOL_PHY_EDPD_DISABLE 0

+/*
+ * BroadR-Reach Mode Control
+ */
+#define ETHTOOL_PHY_BRR_MODE_ON 1
+#define ETHTOOL_PHY_BRR_MODE_OFF 0
+
enum phy_tunable_id {
ETHTOOL_PHY_ID_UNSPEC,
ETHTOOL_PHY_DOWNSHIFT,
ETHTOOL_PHY_FAST_LINK_DOWN,
ETHTOOL_PHY_EDPD,
+ ETHTOOL_PHY_BRR_MODE,
/*
* Add your fresh new phy tunable attribute above and remember to update
* phy_tunable_strings[] in net/ethtool/common.c
@@ -1790,7 +1797,11 @@ 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_1BR10_BIT = 102,
+ ETHTOOL_LINK_MODE_2BR10_BIT = 103,
+ ETHTOOL_LINK_MODE_1BR100_BIT = 104,
+ ETHTOOL_LINK_MODE_2BR100_BIT = 105,
+ ETHTOOL_LINK_MODE_4BR100_BIT = 106,
/* must be last entry */
__ETHTOOL_LINK_MODE_MASK_NBITS
};
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 6b2a360dcdf0..81ad9d2aef1f 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -98,6 +98,7 @@ phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN] = {
[ETHTOOL_PHY_DOWNSHIFT] = "phy-downshift",
[ETHTOOL_PHY_FAST_LINK_DOWN] = "phy-fast-link-down",
[ETHTOOL_PHY_EDPD] = "phy-energy-detect-power-down",
+ [ETHTOOL_PHY_BRR_MODE] = "phy-broadrreach-mode",
};

#define __LINK_MODE_NAME(speed, type, duplex) \
@@ -211,6 +212,11 @@ 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_SPECIAL_MODE_NAME(1BR10, "1BR10"),
+ __DEFINE_SPECIAL_MODE_NAME(2BR10, "2BR10"),
+ __DEFINE_SPECIAL_MODE_NAME(1BR100, "1BR100"),
+ __DEFINE_SPECIAL_MODE_NAME(2BR100, "2BR100"),
+ __DEFINE_SPECIAL_MODE_NAME(4BR100, "4BR100"),
};
static_assert(ARRAY_SIZE(link_mode_names) == __ETHTOOL_LINK_MODE_MASK_NBITS);

@@ -374,6 +380,31 @@ 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),
+ [ETHTOOL_LINK_MODE_1BR10_BIT] = {
+ .speed = SPEED_10,
+ .lanes = 1,
+ .duplex = DUPLEX_FULL,
+ },
+ [ETHTOOL_LINK_MODE_2BR10_BIT] = {
+ .speed = SPEED_10,
+ .lanes = 2,
+ .duplex = DUPLEX_FULL,
+ },
+ [ETHTOOL_LINK_MODE_1BR100_BIT] = {
+ .speed = SPEED_100,
+ .lanes = 1,
+ .duplex = DUPLEX_FULL,
+ },
+ [ETHTOOL_LINK_MODE_2BR100_BIT] = {
+ .speed = SPEED_100,
+ .lanes = 2,
+ .duplex = DUPLEX_FULL,
+ },
+ [ETHTOOL_LINK_MODE_4BR100_BIT] = {
+ .speed = SPEED_100,
+ .lanes = 4,
+ .duplex = DUPLEX_FULL,
+ },
};
static_assert(ARRAY_SIZE(link_mode_params) == __ETHTOOL_LINK_MODE_MASK_NBITS);

diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 5a55270aa86e..9e68c8562fa3 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -2722,6 +2722,7 @@ static int ethtool_phy_tunable_valid(const struct ethtool_tunable *tuna)
switch (tuna->id) {
case ETHTOOL_PHY_DOWNSHIFT:
case ETHTOOL_PHY_FAST_LINK_DOWN:
+ case ETHTOOL_PHY_BRR_MODE:
if (tuna->len != sizeof(u8) ||
tuna->type_id != ETHTOOL_TUNABLE_U8)
return -EINVAL;
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index b07aa71b24ec..98cb5a22a281 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -4673,7 +4673,7 @@ static void __init tcp_struct_check(void)
CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, app_limited);
CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, rcv_wnd);
CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, rx_opt);
- CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);
+// CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);

/* RX read-write hotpath cache lines */
CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, bytes_received);
--
2.39.2



2024-04-16 14:11:48

by Andrew Lunn

[permalink] [raw]
Subject: Re: [PATCH] net: phy: bcm54811: add support for BroadR-Reach mode

> @@ -258,6 +257,9 @@ static const struct phy_setting settings[] = {
> PHY_SETTING( 100, HALF, 100baseT_Half ),
> PHY_SETTING( 100, HALF, 100baseFX_Half ),
> PHY_SETTING( 100, FULL, 100baseFX_Full ),
> + PHY_SETTING( 100, FULL, 4BR100 ),
> + PHY_SETTING( 100, FULL, 2BR100 ),
> + PHY_SETTING( 100, FULL, 1BR100 ),

Please could you explain the name convention. IEEE puts the speed
first, then some letters to indicate the media type, and then a number
for the number of pairs. Why is this not followed here? 100BaseBR4?
100BaseBR2? 100BaseBR1? Are these names part of the BroadR-Reach
standard?

Also, is there any compatibility? Are 100BaseT1 and 1BR100 compatible?

Andrew

2024-04-16 23:49:04

by Florian Fainelli

[permalink] [raw]
Subject: Re: [PATCH] net: phy: bcm54811: add support for BroadR-Reach mode

On 4/16/24 05:38, Kamil Horák - 2N wrote:
> Enable the BroadR-Reach link modes for BCM54811 PHY by Broadcom.
> This allows for two-wire Ethernet at 10 or 100MBit using BroadR-Reach
> mode and also for other BroadR-Reach modes using more than one pair.

In terms of organization, it seems like you could do at least 3 patches:

- one patch that adds the new BroadR-Reach link modes and ethtool plumbing
- one patch that adds all of the register definitions to brcmphy.h which
can be easily skipped
- one patch that updates broadcom.c and bcm-phy-lib.[ch] to implement
BroadR-Reach

I am happy that you introduced an ethtool tunable, rather than key it
off Device Tree or module parameter, so kudos for doing that!

Need to wrap my head a bit as to what to do with the overlapping
register mapping, and whether it would not be simpler to do some sort of
register level remapping of values, rather than provide different
callbacks for read_status, config_aneg, etc.

>
> Signed-off-by: Kamil Horák - 2N <[email protected]>
> ---
> drivers/net/phy/broadcom.c | 432 ++++++++++++++++++++++++++++++++++-
> drivers/net/phy/phy-core.c | 13 +-
> include/linux/brcmphy.h | 91 +++++++-
> include/uapi/linux/ethtool.h | 13 +-
> net/ethtool/common.c | 31 +++
> net/ethtool/ioctl.c | 1 +
> net/ipv4/tcp.c | 2 +-

This file should really not be modified, you must have made this
temporary change to build test your changes, but this is now fixed in
net-next as of a few days ago.

> 7 files changed, 567 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
> index 370e4ed45098..aeb49b566aca 100644
> --- a/drivers/net/phy/broadcom.c
> +++ b/drivers/net/phy/broadcom.c
> @@ -553,18 +553,46 @@ 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 bcm54811_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) ?
> + ETHTOOL_PHY_BRR_MODE_ON : ETHTOOL_PHY_BRR_MODE_OFF;
> +
> + return 0;
> +}
> +
> +static int bcm54811_set_brrmode(struct phy_device *phydev, u8 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;
>
> + /* 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;
> +
> err = bcm54xx_config_init(phydev);
>
> /* Enable CLK125 MUX on LED4 if ref clock is enabled. */
> @@ -576,16 +604,151 @@ static int bcm54811_config_init(struct phy_device *phydev)
> return err;
> }
>
> - return err;
> + /* Configure BroadR-Reach function. */
> + return bcm54811_set_brrmode(phydev, ETHTOOL_PHY_BRR_MODE_OFF);
> +}
> +
> +static int bcm_setup_master_slave(struct phy_device *phydev)

The namespace in this driver is such that we prefix with bcm54xx_ or
bcm<phy number>, this is generic so this could go to bcm-phy-lib.[ch] as
a matter of fact.

> +{
> + 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:
> + break;
> + 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);
> +}
> +
> +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
> + *
> + * A small helper function that translates linkmode advertisement
> + * settings to phy autonegotiation advertisements for the
> + * MII_BCM54XX_LREANAA register.
> + */
> +static inline u32 bcm_linkmode_adv_to_mii_adv_t(unsigned long *advertising)
> +{
> + u32 result = 0;
> +
> + if (linkmode_test_bit(ETHTOOL_LINK_MODE_1BR10_BIT, advertising))
> + result |= LREANAA_10_1PAIR;
> + if (linkmode_test_bit(ETHTOOL_LINK_MODE_2BR10_BIT, advertising))
> + result |= LREANAA_10_2PAIR;
> + if (linkmode_test_bit(ETHTOOL_LINK_MODE_1BR100_BIT, advertising))
> + result |= LREANAA_100_1PAIR;
> + if (linkmode_test_bit(ETHTOOL_LINK_MODE_2BR100_BIT, advertising))
> + result |= LREANAA_100_2PAIR;
> + if (linkmode_test_bit(ETHTOOL_LINK_MODE_4BR100_BIT, advertising))
> + result |= LREANAA_100_4PAIR;
> + 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;
> +}
> +
> +/**
> + * 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.
> + */
> +static 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 > 0 ? 1 : 0;
> +}
> +
> +static 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) /* error */
> + return err;
> + else if (err)
> + changed = true;
> +
> + return genphy_check_and_restart_aneg(phydev, changed);
> }
>
> static int bcm5481_config_aneg(struct phy_device *phydev)
> {

I would create a bcm54811_config_aneg() function here which checks for
the BRR mode.

> struct device_node *np = phydev->mdio.dev.of_node;
> int ret;
> + u8 brr_mode;
>
> /* Aneg firstly. */
> - ret = genphy_config_aneg(phydev);
> + ret = bcm54811_get_brrmode(phydev, &brr_mode);
> + if (ret)
> + return ret;
> +
> + if (brr_mode == ETHTOOL_PHY_BRR_MODE_ON)
> + ret = bcm_config_aneg(phydev, false);
> + else
> + ret = genphy_config_aneg(phydev);
>
> /* Then we can set up the delay. */
> bcm54xx_config_clock_delay(phydev);
> @@ -1062,6 +1225,253 @@ static void bcm54xx_link_change_notify(struct phy_device *phydev)
> bcm_phy_write_exp(phydev, MII_BCM54XX_EXP_EXP08, ret);
> }
>
> +static int bcm54811_read_abilities(struct phy_device *phydev)
> +{
> + int val, err;
> + int i;
> + static const int modes_array[] = {ETHTOOL_LINK_MODE_1BR100_BIT,
> + ETHTOOL_LINK_MODE_4BR100_BIT,
> + ETHTOOL_LINK_MODE_2BR100_BIT,
> + ETHTOOL_LINK_MODE_2BR10_BIT,
> + ETHTOOL_LINK_MODE_1BR10_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};
> +
> + u8 brr_mode;
> +
> + for (i = 0; i < ARRAY_SIZE(modes_array); i++)
> + linkmode_clear_bit(modes_array[i], phydev->supported);
> +
> + err = bcm54811_get_brrmode(phydev, &brr_mode);
> +
> + if (!err) {

Please do an early return so you can reduce the indentation here, and
elsewhere, too.
--
Florian


Attachments:
smime.p7s (4.12 kB)
S/MIME Cryptographic Signature

2024-04-17 02:17:00

by Florian Fainelli

[permalink] [raw]
Subject: Re: [PATCH] net: phy: bcm54811: add support for BroadR-Reach mode

On 4/16/24 07:10, Andrew Lunn wrote:
>> @@ -258,6 +257,9 @@ static const struct phy_setting settings[] = {
>> PHY_SETTING( 100, HALF, 100baseT_Half ),
>> PHY_SETTING( 100, HALF, 100baseFX_Half ),
>> PHY_SETTING( 100, FULL, 100baseFX_Full ),
>> + PHY_SETTING( 100, FULL, 4BR100 ),
>> + PHY_SETTING( 100, FULL, 2BR100 ),
>> + PHY_SETTING( 100, FULL, 1BR100 ),
>
> Please could you explain the name convention. IEEE puts the speed
> first, then some letters to indicate the media type, and then a number
> for the number of pairs. Why is this not followed here? 100BaseBR4?
> 100BaseBR2? 100BaseBR1? Are these names part of the BroadR-Reach
> standard?

The datasheet refers to those mode as 1BR-100 so it seems to make sense
to define them the same way here.

>
> Also, is there any compatibility? Are 100BaseT1 and 1BR100 compatible?

As far as I could glean, they are supposed to be:

https://www.electronicdesign.com/markets/automotive/article/21806576/whats-the-difference-between-broadr-reach-and-100base-t1

Given that part, it makes me wonder if it would not be less confusing to
map the existing T1 link modes onto what the BCM54811 PHY supports,
Kamil, what do you think?
--
Florian


Attachments:
smime.p7s (4.12 kB)
S/MIME Cryptographic Signature

2024-04-25 12:59:30

by Kamil Horák - 2N

[permalink] [raw]
Subject: Re: [PATCH] net: phy: bcm54811: add support for BroadR-Reach mode


On 4/17/24 01:46, Florian Fainelli wrote:
> On 4/16/24 07:10, Andrew Lunn wrote:
>>> @@ -258,6 +257,9 @@ static const struct phy_setting settings[] = {
>>>       PHY_SETTING(    100, HALF,    100baseT_Half        ),
>>>       PHY_SETTING(    100, HALF,    100baseFX_Half        ),
>>>       PHY_SETTING(    100, FULL,    100baseFX_Full        ),
>>> +    PHY_SETTING(    100, FULL,    4BR100            ),
>>> +    PHY_SETTING(    100, FULL,    2BR100            ),
>>> +    PHY_SETTING(    100, FULL,    1BR100            ),
>>
>> Please could you explain the name convention. IEEE puts the speed
>> first, then some letters to indicate the media type, and then a number
>> for the number of pairs. Why is this not followed here? 100BaseBR4?
>> 100BaseBR2? 100BaseBR1? Are these names part of the BroadR-Reach
>> standard?
>
> The datasheet refers to those mode as 1BR-100 so it seems to make
> sense to define them the same way here.
>
>>
>> Also, is there any compatibility? Are 100BaseT1 and 1BR100 compatible?
>
> As far as I could glean, they are supposed to be:
>
> https://www.electronicdesign.com/markets/automotive/article/21806576/whats-the-difference-between-broadr-reach-and-100base-t1
>
>
> Given that part, it makes me wonder if it would not be less confusing
> to map the existing T1 link modes onto what the BCM54811 PHY supports,
> Kamil, what do you think?
1BR100 is really same as 100BASE-T1, in fact, the Broadcom's
BroadR-Reach 1BR100 became 100BASE-T1 standard (IEEE 802.3bw). However,
there is also 1BR10 to be implemented, which is neither 10BASE-T1S nor
10BASE-T1L.
Thus, there would be 100BASE-T1 and the remaining BRR modes (1BR10,
2BR10, 2BR100, 4BR100), let alone the fact that it is questionable
whether anyone would need the modes with more than one wire pair.
So yes, for 100 MBit alone sure it would be better to make it 100BASE-T1
and it should be interoperable with another device using same link mode
on non-Broadcom PHY.
Note that the BRR modes are always full duplex

Shall we change the 1BR100 to 100BASE-T1 and leave the rest?

Option 1: 1BR10, 2BR10, 1BR100, 2BR100, 4BR100 (= leave as-is)

Option 2: 100BaseT1_Full, 1BR10, 2BR10, 2BR100, 4BR100

Option 3: 100BaseT1_Full, 1BR10 (= leave out the modes that are
practically unusable)

In our application, 2-wire 10 and 100 MBit is used, the rest could be
for someone else or just to map all PHY capabilities.



2024-04-25 15:04:40

by Andrew Lunn

[permalink] [raw]
Subject: Re: [PATCH] net: phy: bcm54811: add support for BroadR-Reach mode

> 1BR100 is really same as 100BASE-T1, in fact, the Broadcom's BroadR-Reach
> 1BR100 became 100BASE-T1 standard (IEEE 802.3bw). However, there is also
> 1BR10 to be implemented, which is neither 10BASE-T1S nor 10BASE-T1L.
> Thus, there would be 100BASE-T1 and the remaining BRR modes (1BR10, 2BR10,
> 2BR100, 4BR100), let alone the fact that it is questionable whether anyone
> would need the modes with more than one wire pair.
> So yes, for 100 MBit alone sure it would be better to make it 100BASE-T1 and
> it should be interoperable with another device using same link mode on
> non-Broadcom PHY.
> Note that the BRR modes are always full duplex
>
> Shall we change the 1BR100 to 100BASE-T1 and leave the rest?
>
> Option 1: 1BR10, 2BR10, 1BR100, 2BR100, 4BR100 (= leave as-is)
>
> Option 2: 100BaseT1_Full, 1BR10, 2BR10, 2BR100, 4BR100
>
> Option 3: 100BaseT1_Full, 1BR10 (= leave out the modes that are practically
> unusable)
>
> In our application, 2-wire 10 and 100 MBit is used, the rest could be for
> someone else or just to map all PHY capabilities.

I would suggest you implement what you actually need. So option 3.

Andrew