Re: [PATCH] lan743x: Added fixed link support

Andrew Lunn
2020-05-21T14:04:32Z

On Wed, May 20, 2020 at 07:10:06PM +0200, Roelof Berg wrote:

Hi Roelof

Here is how i would do this. I don't like this MII bus snooping. It is
a microchip propriety's thing, which is not well understood. It adds
no value over just doing what every other MAC driver does in the
link_change callback, which lots of people understand.

I also removed all OF handing from within the callback. And i unified
fixed-link and normal PHY.

This is compile tested only, so is probably broken...

Andrew

diff --git a/drivers/net/ethernet/microchip/lan743x_ethtool.c b/drivers/net/ethernet/microchip/lan743x_ethtool.c
index 3a0b289d9771..c533d06fbe3a 100644
--- a/drivers/net/ethernet/microchip/lan743x_ethtool.c
+++ b/drivers/net/ethernet/microchip/lan743x_ethtool.c
@@ -2,11 +2,11 @@
/* Copyright (C) 2018 Microchip Technology Inc. */

#include <linux/netdevice.h>
-#include "lan743x_main.h"
-#include "lan743x_ethtool.h"
#include <linux/net_tstamp.h>
#include <linux/pci.h>
#include <linux/phy.h>
+#include "lan743x_main.h"
+#include "lan743x_ethtool.h"

/* eeprom */
#define LAN743X_EEPROM_MAGIC (0x74A5)
diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index a43140f7b5eb..5aaa0ac96970 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -8,7 +8,10 @@
#include <linux/crc32.h>
#include <linux/microchipphy.h>
#include <linux/net_tstamp.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
#include <linux/phy.h>
+#include <linux/phy_fixed.h>
#include <linux/rtnetlink.h>
#include <linux/iopoll.h>
#include <linux/crc16.h>
@@ -798,9 +801,9 @@ static int lan743x_mac_init(struct lan743x_adapter *adapter)

netdev = adapter->netdev;

- /* setup auto duplex, and speed detection */
+ /* disable auto duplex, and speed detection. Phylib does that */
data = lan743x_csr_read(adapter, MAC_CR);
- data |= MAC_CR_ADD_ | MAC_CR_ASD_;
+ data &= ~(MAC_CR_ADD_ | MAC_CR_ASD_);
data |= MAC_CR_CNTR_RST_;
lan743x_csr_write(adapter, MAC_CR, data);

@@ -946,6 +949,7 @@ static void lan743x_phy_link_status_change(struct net_device *netdev)
{
struct lan743x_adapter *adapter = netdev_priv(netdev);
struct phy_device *phydev = netdev->phydev;
+ u32 data;

phy_print_status(phydev);
if (phydev->state == PHY_RUNNING) {
@@ -953,6 +957,39 @@ static void lan743x_phy_link_status_change(struct net_device *netdev)
int remote_advertisement = 0;
int local_advertisement = 0;

+ data = lan743x_csr_read(adapter, MAC_CR);
+
+ /* set interface mode */
+ if (phy_interface_mode_is_rgmii(adapter->phy_mode))
+ /* RGMII */
+ data &= ~MAC_CR_MII_EN_;
+ else
+ /* GMII */
+ data |= MAC_CR_MII_EN_;
+
+ /* set fixed duplex mode */
+ if (phydev->duplex)
+ data |= MAC_CR_DPX_;
+ else
+ data &= ~MAC_CR_DPX_;
+
+ /* set fixed bus speed */
+ switch (phydev->speed) {
+ case SPEED_10:
+ data &= ~MAC_CR_CFG_H_;
+ data &= ~MAC_CR_CFG_L_;
+ break;
+ case SPEED_100:
+ data &= ~MAC_CR_CFG_H_;
+ data |= MAC_CR_CFG_L_;
+ break;
+ case SPEED_1000:
+ data |= MAC_CR_CFG_H_;
+ data |= MAC_CR_CFG_L_;
+ break;
+ }
+ lan743x_csr_write(adapter, MAC_CR, data);
+
memset(&ksettings, 0, sizeof(ksettings));
phy_ethtool_get_link_ksettings(netdev, &ksettings);
local_advertisement =
@@ -974,26 +1011,53 @@ static void lan743x_phy_close(struct lan743x_adapter *adapter)

phy_stop(netdev->phydev);
phy_disconnect(netdev->phydev);
+ if (of_phy_is_fixed_link(adapter->pdev->dev.of_node))
+ of_phy_deregister_fixed_link(adapter->pdev->dev.of_node);
netdev->phydev = NULL;
}

static int lan743x_phy_open(struct lan743x_adapter *adapter)
{
struct lan743x_phy *phy = &adapter->phy;
+ struct device_node *phynode;
struct phy_device *phydev;
struct net_device *netdev;
int ret = -EIO;

netdev = adapter->netdev;
- phydev = phy_find_first(adapter->mdiobus);
- if (!phydev)
- goto return_error;

- ret = phy_connect_direct(netdev, phydev,
- lan743x_phy_link_status_change,
- PHY_INTERFACE_MODE_GMII);
- if (ret)
- goto return_error;
+ phynode = of_node_get(adapter->pdev->dev.of_node);
+ adapter->phy_mode = PHY_INTERFACE_MODE_GMII;
+
+ if (phynode) {
+ of_get_phy_mode(phynode, &adapter->phy_mode);
+
+ if (of_phy_is_fixed_link(phynode)) {
+ ret = of_phy_register_fixed_link(phynode);
+ if (ret) {
+ netdev_err(netdev,
+ "cannot register fixed PHY\n");
+ of_node_put(phynode);
+ goto return_error;
+ }
+ }
+ phydev = of_phy_connect(netdev, phynode,
+ lan743x_phy_link_status_change, 0,
+ adapter->phy_mode);
+ of_node_put(phynode);
+ if (!phydev)
+ goto return_error;
+ } else {
+ phydev = phy_find_first(adapter->mdiobus);
+ if (!phydev)
+ goto return_error;
+
+ ret = phy_connect_direct(netdev, phydev,
+ lan743x_phy_link_status_change,
+ adapter->phy_mode);
+ if (ret)
+ goto return_error;
+ }

/* MAC doesn't support 1000T Half */
phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h
index 3b02eeae5f45..f769903538e4 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.h
+++ b/drivers/net/ethernet/microchip/lan743x_main.h
@@ -104,10 +104,14 @@
((value << 0) & FCT_FLOW_CTL_ON_THRESHOLD_)

#define MAC_CR (0x100)
+#define MAC_CR_MII_EN_ BIT(19)
#define MAC_CR_EEE_EN_ BIT(17)
#define MAC_CR_ADD_ BIT(12)
#define MAC_CR_ASD_ BIT(11)
#define MAC_CR_CNTR_RST_ BIT(5)
+#define MAC_CR_DPX_ BIT(3)
+#define MAC_CR_CFG_H_ BIT(2)
+#define MAC_CR_CFG_L_ BIT(1)
#define MAC_CR_RST_ BIT(0)

#define MAC_RX (0x104)
@@ -698,6 +702,7 @@ struct lan743x_rx {
struct lan743x_adapter {
struct net_device *netdev;
struct mii_bus *mdiobus;
+ phy_interface_t phy_mode;
int msg_enable;
#ifdef CONFIG_PM
u32 wolopts;
diff --git a/drivers/net/ethernet/microchip/lan743x_ptp.c b/drivers/net/ethernet/microchip/lan743x_ptp.c
index 9399f6a98748..b1df214a6973 100644
--- a/drivers/net/ethernet/microchip/lan743x_ptp.c
+++ b/drivers/net/ethernet/microchip/lan743x_ptp.c
@@ -2,12 +2,12 @@
/* Copyright (C) 2018 Microchip Technology Inc. */

#include <linux/netdevice.h>
-#include "lan743x_main.h"
-
+#include <linux/phy.h>
#include <linux/ptp_clock_kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/net_tstamp.h>
+#include "lan743x_main.h"

#include "lan743x_ptp.h"