[PATCH] mvneta: implement SGMII-based in-band link state signaling

From: Stas Sergeev
Date: Tue Mar 31 2015 - 09:25:21 EST

Next message: Boaz Harrosh: "[PATCH 3/6] SQUASHME: pmem: Streamline pmem driver"
Previous message: Michael Wang: "Re: [RFC PATCH 06/11] IB/Verbs: Use management helper has_sa() and cap_sa(), for sa-check"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

When MDIO bus is unavailable (common setup for SGMII), the in-band
signaling must be used to correctly track link state.
This patch enables the in-band status delivery for links state changes, namely:
- link up/down
- link speed
- duplex full/half
fixed_phy link_update() callback is used to update status.

Note: SGMII setup is so common that I think it deserves a separate API
rather than the per-driver handling. There is an alternative implementation
that adds such API:
https://lkml.org/lkml/2015/3/27/346

CC: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
CC: Florian Fainelli <f.fainelli@xxxxxxxxx>
CC: netdev@xxxxxxxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx

Signed-off-by: Stas Sergeev <stsp@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/marvell/mvneta.c | 90 +++++++++++++++++++++++++++++----
1 file changed, 79 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 96208f1..13a2aa2 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -100,6 +100,8 @@
#define MVNETA_TXQ_CMD 0x2448
#define MVNETA_TXQ_DISABLE_SHIFT 8
#define MVNETA_TXQ_ENABLE_MASK 0x000000ff
+#define MVNETA_GMAC_CLOCK_DIVIDER 0x24f4
+#define MVNETA_GMAC_1MS_CLOCK_ENABLE BIT(31)
#define MVNETA_ACC_MODE 0x2500
#define MVNETA_CPU_MAP(cpu) (0x2540 + ((cpu) << 2))
#define MVNETA_CPU_RXQ_ACCESS_ALL_MASK 0x000000ff
@@ -122,6 +124,7 @@
#define MVNETA_TX_INTR_MASK_ALL (0xff << 0)
#define MVNETA_RX_INTR_MASK(nr_rxqs) (((1 << nr_rxqs) - 1) << 8)
#define MVNETA_RX_INTR_MASK_ALL (0xff << 8)
+#define MVNETA_MISCINTR_INTR_MASK BIT(31)

#define MVNETA_INTR_OLD_CAUSE 0x25a8
#define MVNETA_INTR_OLD_MASK 0x25ac
@@ -165,6 +168,7 @@
#define MVNETA_GMAC_MAX_RX_SIZE_MASK 0x7ffc
#define MVNETA_GMAC0_PORT_ENABLE BIT(0)
#define MVNETA_GMAC_CTRL_2 0x2c08
+#define MVNETA_GMAC2_INBAND_AN_ENABLE BIT(0)
#define MVNETA_GMAC2_PCS_ENABLE BIT(3)
#define MVNETA_GMAC2_PORT_RGMII BIT(4)
#define MVNETA_GMAC2_PORT_RESET BIT(6)
@@ -180,9 +184,11 @@
#define MVNETA_GMAC_AUTONEG_CONFIG 0x2c0c
#define MVNETA_GMAC_FORCE_LINK_DOWN BIT(0)
#define MVNETA_GMAC_FORCE_LINK_PASS BIT(1)
+#define MVNETA_GMAC_INBAND_AN_ENABLE BIT(2)
#define MVNETA_GMAC_CONFIG_MII_SPEED BIT(5)
#define MVNETA_GMAC_CONFIG_GMII_SPEED BIT(6)
#define MVNETA_GMAC_AN_SPEED_EN BIT(7)
+#define MVNETA_GMAC_AN_FLOW_CTRL_EN BIT(11)
#define MVNETA_GMAC_CONFIG_FULL_DUPLEX BIT(12)
#define MVNETA_GMAC_AN_DUPLEX_EN BIT(13)
#define MVNETA_MIB_COUNTERS_BASE 0x3080
@@ -304,6 +310,7 @@ struct mvneta_port {
unsigned int link;
unsigned int duplex;
unsigned int speed;
+ int use_inband_status:1;
};

/* The mvneta_tx_desc and mvneta_rx_desc structures describe the
@@ -994,6 +1001,20 @@ static void mvneta_defaults_set(struct mvneta_port *pp)
val &= ~MVNETA_PHY_POLLING_ENABLE;
mvreg_write(pp, MVNETA_UNIT_CONTROL, val);

+ if (pp->use_inband_status) {
+ val = mvreg_read(pp, MVNETA_GMAC_AUTONEG_CONFIG);
+ val &= ~(MVNETA_GMAC_FORCE_LINK_PASS |
+ MVNETA_GMAC_FORCE_LINK_DOWN |
+ MVNETA_GMAC_AN_FLOW_CTRL_EN);
+ val |= MVNETA_GMAC_INBAND_AN_ENABLE |
+ MVNETA_GMAC_AN_SPEED_EN |
+ MVNETA_GMAC_AN_DUPLEX_EN;
+ mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG, val);
+ val = mvreg_read(pp, MVNETA_GMAC_CLOCK_DIVIDER);
+ val |= MVNETA_GMAC_1MS_CLOCK_ENABLE;
+ mvreg_write(pp, MVNETA_GMAC_CLOCK_DIVIDER, val);
+ }
+
mvneta_set_ucast_table(pp, -1);
mvneta_set_special_mcast_table(pp, -1);
mvneta_set_other_mcast_table(pp, -1);
@@ -2043,6 +2064,23 @@ static irqreturn_t mvneta_isr(int irq, void *dev_id)
return IRQ_HANDLED;
}

+static int mvneta_fixed_link_update(struct net_device *dev,
+ struct fixed_phy_status *status)
+{
+ struct mvneta_port *pp = netdev_priv(dev);
+ u32 gmac_stat = mvreg_read(pp, MVNETA_GMAC_STATUS);
+
+ status->link = !!(gmac_stat & MVNETA_GMAC_LINK_UP);
+ if (gmac_stat & MVNETA_GMAC_SPEED_1000)
+ status->speed = SPEED_1000;
+ else if (gmac_stat & MVNETA_GMAC_SPEED_100)
+ status->speed = SPEED_100;
+ else
+ status->speed = SPEED_10;
+ status->duplex = !!(gmac_stat & MVNETA_GMAC_FULL_DUPLEX);
+ return 0;
+}
+
/* NAPI handler
* Bits 0 - 7 of the causeRxTx register indicate that are transmitted
* packets on the corresponding TXQ (Bit 0 is for TX queue 1).
@@ -2063,8 +2101,12 @@ static int mvneta_poll(struct napi_struct *napi, int budget)
}

/* Read cause register */
- cause_rx_tx = mvreg_read(pp, MVNETA_INTR_NEW_CAUSE) &
- (MVNETA_RX_INTR_MASK(rxq_number) | MVNETA_TX_INTR_MASK(txq_number));
+ cause_rx_tx = mvreg_read(pp, MVNETA_INTR_NEW_CAUSE);
+ if (cause_rx_tx & MVNETA_MISCINTR_INTR_MASK) {
+ /* since phylib uses polling, not much to do here...
+ * Any way to tell phylib to do the poll NOW? */
+ mvreg_write(pp, MVNETA_INTR_MISC_CAUSE, 0);
+ }

/* Release Tx descriptors */
if (cause_rx_tx & MVNETA_TX_INTR_MASK_ALL) {
@@ -2109,7 +2151,9 @@ static int mvneta_poll(struct napi_struct *napi, int budget)
napi_complete(napi);
local_irq_save(flags);
mvreg_write(pp, MVNETA_INTR_NEW_MASK,
- MVNETA_RX_INTR_MASK(rxq_number) | MVNETA_TX_INTR_MASK(txq_number));
+ MVNETA_RX_INTR_MASK(rxq_number) |
+ MVNETA_TX_INTR_MASK(txq_number) |
+ MVNETA_MISCINTR_INTR_MASK);
local_irq_restore(flags);
}

@@ -2373,7 +2417,13 @@ static void mvneta_start_dev(struct mvneta_port *pp)

/* Unmask interrupts */
mvreg_write(pp, MVNETA_INTR_NEW_MASK,
- MVNETA_RX_INTR_MASK(rxq_number) | MVNETA_TX_INTR_MASK(txq_number));
+ MVNETA_RX_INTR_MASK(rxq_number) |
+ MVNETA_TX_INTR_MASK(txq_number) |
+ MVNETA_MISCINTR_INTR_MASK);
+ mvreg_write(pp, MVNETA_INTR_MISC_MASK,
+ MVNETA_CAUSE_PHY_STATUS_CHANGE |
+ MVNETA_CAUSE_LINK_CHANGE |
+ MVNETA_CAUSE_PSC_SYNC_CHANGE);

phy_start(pp->phy_dev);
netif_tx_start_all_queues(pp->dev);
@@ -2523,9 +2573,7 @@ static void mvneta_adjust_link(struct net_device *ndev)
val = mvreg_read(pp, MVNETA_GMAC_AUTONEG_CONFIG);
val &= ~(MVNETA_GMAC_CONFIG_MII_SPEED |
MVNETA_GMAC_CONFIG_GMII_SPEED |
- MVNETA_GMAC_CONFIG_FULL_DUPLEX |
- MVNETA_GMAC_AN_SPEED_EN |
- MVNETA_GMAC_AN_DUPLEX_EN);
+ MVNETA_GMAC_CONFIG_FULL_DUPLEX);

if (phydev->duplex)
val |= MVNETA_GMAC_CONFIG_FULL_DUPLEX;
@@ -2554,12 +2602,24 @@ static void mvneta_adjust_link(struct net_device *ndev)

if (status_change) {
if (phydev->link) {
- u32 val = mvreg_read(pp, MVNETA_GMAC_AUTONEG_CONFIG);
- val |= (MVNETA_GMAC_FORCE_LINK_PASS |
- MVNETA_GMAC_FORCE_LINK_DOWN);
- mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG, val);
+ if (!pp->use_inband_status) {
+ u32 val = mvreg_read(pp,
+ MVNETA_GMAC_AUTONEG_CONFIG);
+ val &= ~MVNETA_GMAC_FORCE_LINK_DOWN;
+ val |= MVNETA_GMAC_FORCE_LINK_PASS;
+ mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG,
+ val);
+ }
mvneta_port_up(pp);
} else {
+ if (!pp->use_inband_status) {
+ u32 val = mvreg_read(pp,
+ MVNETA_GMAC_AUTONEG_CONFIG);
+ val &= ~MVNETA_GMAC_FORCE_LINK_PASS;
+ val |= MVNETA_GMAC_FORCE_LINK_DOWN;
+ mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG,
+ val);
+ }
mvneta_port_down(pp);
}
phy_print_status(phydev);
@@ -2576,6 +2636,7 @@ static int mvneta_mdio_probe(struct mvneta_port *pp)
netdev_err(pp->dev, "could not find the PHY\n");
return -ENODEV;
}
+ fixed_phy_set_link_update(phy_dev, mvneta_fixed_link_update);

phy_dev->supported &= PHY_GBIT_FEATURES;
phy_dev->advertising = phy_dev->supported;
@@ -2590,6 +2651,7 @@ static int mvneta_mdio_probe(struct mvneta_port *pp)

static void mvneta_mdio_remove(struct mvneta_port *pp)
{
+ fixed_phy_set_link_update(pp->phy_dev, NULL);
phy_disconnect(pp->phy_dev);
pp->phy_dev = NULL;
}
@@ -2910,6 +2972,9 @@ static int mvneta_port_power_up(struct mvneta_port *pp, int phy_mode)
return -EINVAL;
}

+ if (pp->use_inband_status)
+ ctrl |= MVNETA_GMAC2_INBAND_AN_ENABLE;
+
/* Cancel Port Reset */
ctrl &= ~MVNETA_GMAC2_PORT_RESET;
mvreg_write(pp, MVNETA_GMAC_CTRL_2, ctrl);
@@ -2934,6 +2999,7 @@ static int mvneta_probe(struct platform_device *pdev)
char hw_mac_addr[ETH_ALEN];
const char *mac_from;
int phy_mode;
+ int fixed_phy = 0;
int err;

/* Our multiqueue support is not complete, so for now, only
@@ -2967,6 +3033,7 @@ static int mvneta_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "cannot register fixed PHY\n");
goto err_free_irq;
}
+ fixed_phy = 1;

/* In the case of a fixed PHY, the DT node associated
* to the PHY is the Ethernet MAC DT node.
@@ -2990,6 +3057,7 @@ static int mvneta_probe(struct platform_device *pdev)
pp = netdev_priv(dev);
pp->phy_node = phy_node;
pp->phy_interface = phy_mode;
+ pp->use_inband_status = (phy_mode == PHY_INTERFACE_MODE_SGMII) && fixed_phy;

pp->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(pp->clk)) {
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Next message: Boaz Harrosh: "[PATCH 3/6] SQUASHME: pmem: Streamline pmem driver"
Previous message: Michael Wang: "Re: [RFC PATCH 06/11] IB/Verbs: Use management helper has_sa() and cap_sa(), for sa-check"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]