Re: [PATCH net-next 1/4] drivers: net: xgene-v2: Add MDIO support

[Iyappan Subramanian]

On Tue, Mar 21, 2017 at 1:35 PM, Andrew Lunn  wrote:
>> @@ -511,9 +512,9 @@ static int xge_close(struct net_device *ndev)
>>  {
>>   struct xge_pdata *pdata = netdev_priv(ndev);
>>
>> - netif_carrier_off(ndev);
>>   netif_stop_queue(ndev);
>>   xge_mac_disable(pdata);
>> + phy_stop(ndev->phydev);
>>
>>   xge_intr_disable(pdata);
>>   xge_free_irq(ndev);
>> @@ -683,9 +684,14 @@ static int xge_probe(struct platform_device *pdev)
>>   if (ret)
>>   goto err;
>>
>> + spin_lock_init(>mdio_lock);
>> +
>
> ...
>
>> +static int xge_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 
>> data)
>> +{
>> + struct xge_pdata *pdata = bus->priv;
>> + u32 done, val = 0;
>> + u8 wait = 10;
>> + int ret = 0;
>> +
>> + spin_lock(>mdio_lock);
>> +
>> + SET_REG_BITS(, PHY_ADDR, phy_id);
>> + SET_REG_BITS(, REG_ADDR, reg);
>> + xge_wr_csr(pdata, MII_MGMT_ADDRESS, val);
>> +
>> + xge_wr_csr(pdata, MII_MGMT_CONTROL, data);
>> + do {
>> + usleep_range(5, 10);
>> + done = xge_rd_csr(pdata, MII_MGMT_INDICATORS);
>> + } while ((done & MII_MGMT_BUSY) && wait--);
>> +
>> + if (done & MII_MGMT_BUSY) {
>> + dev_err(>dev, "MII_MGMT write failed\n");
>> + ret = -ETIMEDOUT;
>> + }
>> +
>> + spin_unlock(>mdio_lock);
>> +
>> + return ret;
>> +}
>> +
>> +static int xge_mdio_read(struct mii_bus *bus, int phy_id, int reg)
>> +{
>> + struct xge_pdata *pdata = bus->priv;
>> + u32 data, done, val = 0;
>> + u8 wait = 10;
>> +
>> + spin_lock(>mdio_lock);
>> +
>
> Hi Iyappan
>
> Please could you explain what this lock is protecting which the
> mii_bus mdio_lock in mdio_bus.c is not protecting?

Hi Keyur,

Please could you explain what this lock is protecting which the
mii_bus mdio_lock in mdio_bus.c is not protecting?

I agree with him.  Actually there is a mutex on mdio_bus.  So the mdio
bus read and write are locked.  we don't need the lock.

Do you agree ?


>
> Thanks
> Andrew

Re: [PATCH net-next 1/4] drivers: net: xgene-v2: Add MDIO support

[Andrew Lunn]

> @@ -511,9 +512,9 @@ static int xge_close(struct net_device *ndev)
>  {
>   struct xge_pdata *pdata = netdev_priv(ndev);
>  
> - netif_carrier_off(ndev);
>   netif_stop_queue(ndev);
>   xge_mac_disable(pdata);
> + phy_stop(ndev->phydev);
>  
>   xge_intr_disable(pdata);
>   xge_free_irq(ndev);
> @@ -683,9 +684,14 @@ static int xge_probe(struct platform_device *pdev)
>   if (ret)
>   goto err;
>  
> + spin_lock_init(>mdio_lock);
> +

...

> +static int xge_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 data)
> +{
> + struct xge_pdata *pdata = bus->priv;
> + u32 done, val = 0;
> + u8 wait = 10;
> + int ret = 0;
> +
> + spin_lock(>mdio_lock);
> +
> + SET_REG_BITS(, PHY_ADDR, phy_id);
> + SET_REG_BITS(, REG_ADDR, reg);
> + xge_wr_csr(pdata, MII_MGMT_ADDRESS, val);
> +
> + xge_wr_csr(pdata, MII_MGMT_CONTROL, data);
> + do {
> + usleep_range(5, 10);
> + done = xge_rd_csr(pdata, MII_MGMT_INDICATORS);
> + } while ((done & MII_MGMT_BUSY) && wait--);
> +
> + if (done & MII_MGMT_BUSY) {
> + dev_err(>dev, "MII_MGMT write failed\n");
> + ret = -ETIMEDOUT;
> + }
> +
> + spin_unlock(>mdio_lock);
> +
> + return ret;
> +}
> +
> +static int xge_mdio_read(struct mii_bus *bus, int phy_id, int reg)
> +{
> + struct xge_pdata *pdata = bus->priv;
> + u32 data, done, val = 0;
> + u8 wait = 10;
> +
> + spin_lock(>mdio_lock);
> +

Hi Iyappan

Please could you explain what this lock is protecting which the
mii_bus mdio_lock in mdio_bus.c is not protecting?

Thanks
Andrew

[PATCH net-next 1/4] drivers: net: xgene-v2: Add MDIO support

[Iyappan Subramanian]

Added phy management support by using phy abstraction layer APIs.

Signed-off-by: Iyappan Subramanian 
---
 drivers/net/ethernet/apm/xgene-v2/Makefile |   2 +-
 drivers/net/ethernet/apm/xgene-v2/mac.c|   2 +-
 drivers/net/ethernet/apm/xgene-v2/mac.h|   1 +
 drivers/net/ethernet/apm/xgene-v2/main.c   |  13 ++-
 drivers/net/ethernet/apm/xgene-v2/main.h   |   5 +
 drivers/net/ethernet/apm/xgene-v2/mdio.c   | 178 +
 6 files changed, 196 insertions(+), 5 deletions(-)
 create mode 100644 drivers/net/ethernet/apm/xgene-v2/mdio.c

diff --git a/drivers/net/ethernet/apm/xgene-v2/Makefile 
b/drivers/net/ethernet/apm/xgene-v2/Makefile
index 735309c..0fa5975 100644
--- a/drivers/net/ethernet/apm/xgene-v2/Makefile
+++ b/drivers/net/ethernet/apm/xgene-v2/Makefile
@@ -2,5 +2,5 @@
 # Makefile for APM X-Gene Ethernet v2 driver
 #
 
-xgene-enet-v2-objs := main.o mac.o enet.o ring.o
+xgene-enet-v2-objs := main.o mac.o enet.o ring.o mdio.o
 obj-$(CONFIG_NET_XGENE_V2) += xgene-enet-v2.o
diff --git a/drivers/net/ethernet/apm/xgene-v2/mac.c 
b/drivers/net/ethernet/apm/xgene-v2/mac.c
index c3189de..ee431e3 100644
--- a/drivers/net/ethernet/apm/xgene-v2/mac.c
+++ b/drivers/net/ethernet/apm/xgene-v2/mac.c
@@ -27,7 +27,7 @@ void xge_mac_reset(struct xge_pdata *pdata)
xge_wr_csr(pdata, MAC_CONFIG_1, 0);
 }
 
-static void xge_mac_set_speed(struct xge_pdata *pdata)
+void xge_mac_set_speed(struct xge_pdata *pdata)
 {
u32 icm0, icm2, ecm0, mc2;
u32 intf_ctrl, rgmii;
diff --git a/drivers/net/ethernet/apm/xgene-v2/mac.h 
b/drivers/net/ethernet/apm/xgene-v2/mac.h
index 0fce6ae..74397c9 100644
--- a/drivers/net/ethernet/apm/xgene-v2/mac.h
+++ b/drivers/net/ethernet/apm/xgene-v2/mac.h
@@ -101,6 +101,7 @@ static inline u32 xgene_get_reg_bits(u32 var, int pos, int 
len)
 struct xge_pdata;
 
 void xge_mac_reset(struct xge_pdata *pdata);
+void xge_mac_set_speed(struct xge_pdata *pdata);
 void xge_mac_enable(struct xge_pdata *pdata);
 void xge_mac_disable(struct xge_pdata *pdata);
 void xge_mac_init(struct xge_pdata *pdata);
diff --git a/drivers/net/ethernet/apm/xgene-v2/main.c 
b/drivers/net/ethernet/apm/xgene-v2/main.c
index ae76977..10d4aff 100644
--- a/drivers/net/ethernet/apm/xgene-v2/main.c
+++ b/drivers/net/ethernet/apm/xgene-v2/main.c
@@ -500,9 +500,10 @@ static int xge_open(struct net_device *ndev)
 
xge_intr_enable(pdata);
xge_wr_csr(pdata, DMARXCTRL, 1);
+
+   phy_start(ndev->phydev);
xge_mac_enable(pdata);
netif_start_queue(ndev);
-   netif_carrier_on(ndev);
 
return 0;
 }
@@ -511,9 +512,9 @@ static int xge_close(struct net_device *ndev)
 {
struct xge_pdata *pdata = netdev_priv(ndev);
 
-   netif_carrier_off(ndev);
netif_stop_queue(ndev);
xge_mac_disable(pdata);
+   phy_stop(ndev->phydev);
 
xge_intr_disable(pdata);
xge_free_irq(ndev);
@@ -683,9 +684,14 @@ static int xge_probe(struct platform_device *pdev)
if (ret)
goto err;
 
+   spin_lock_init(>mdio_lock);
+
+   ret = xge_mdio_config(ndev);
+   if (ret)
+   goto err;
+
netif_napi_add(ndev, >napi, xge_napi, NAPI_POLL_WEIGHT);
 
-   netif_carrier_off(ndev);
ret = register_netdev(ndev);
if (ret) {
netdev_err(ndev, "Failed to register netdev\n");
@@ -713,6 +719,7 @@ static int xge_remove(struct platform_device *pdev)
dev_close(ndev);
rtnl_unlock();
 
+   xge_mdio_remove(ndev);
unregister_netdev(ndev);
free_netdev(ndev);
 
diff --git a/drivers/net/ethernet/apm/xgene-v2/main.h 
b/drivers/net/ethernet/apm/xgene-v2/main.h
index ada7b0e..3e98bb4 100644
--- a/drivers/net/ethernet/apm/xgene-v2/main.h
+++ b/drivers/net/ethernet/apm/xgene-v2/main.h
@@ -65,11 +65,16 @@ struct xge_pdata {
struct xge_desc_ring *rx_ring;
struct platform_device *pdev;
char irq_name[IRQ_ID_SIZE];
+   struct mii_bus *mdio_bus;
struct net_device *ndev;
struct napi_struct napi;
struct xge_stats stats;
+   spinlock_t mdio_lock; /* mdio lock */
int phy_speed;
u8 nbufs;
 };
 
+int xge_mdio_config(struct net_device *ndev);
+void xge_mdio_remove(struct net_device *ndev);
+
 #endif /* __XGENE_ENET_V2_MAIN_H__ */
diff --git a/drivers/net/ethernet/apm/xgene-v2/mdio.c 
b/drivers/net/ethernet/apm/xgene-v2/mdio.c
new file mode 100644
index 000..43f454d
--- /dev/null
+++ b/drivers/net/ethernet/apm/xgene-v2/mdio.c
@@ -0,0 +1,178 @@
+/*
+ * Applied Micro X-Gene SoC Ethernet v2 Driver
+ *
+ * Copyright (c) 2017, Applied Micro Circuits Corporation
+ * Author(s): Iyappan Subramanian 
+ *   Keyur Chudgar 
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of