[Patch net-next v14 07/13] net: dsa: microchip: lan937x: add phy read and write support

From: Arun Ramadoss
Date: Thu Jun 30 2022 - 06:23:02 EST


This patch add support for the writing and reading of the phy registers.
LAN937x uses the Vphy indirect addressing method for accessing the phys.

Signed-off-by: Arun Ramadoss <arun.ramadoss@xxxxxxxxxxxxx>
---
drivers/net/dsa/microchip/ksz_common.c | 2 +
drivers/net/dsa/microchip/lan937x.h | 2 +
drivers/net/dsa/microchip/lan937x_main.c | 116 +++++++++++++++++++++++
drivers/net/dsa/microchip/lan937x_reg.h | 36 +++++++
4 files changed, 156 insertions(+)

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 07b6f34a437e..67bb4bff4d9b 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -207,6 +207,8 @@ static const struct ksz_dev_ops lan937x_dev_ops = {
.get_port_addr = ksz9477_get_port_addr,
.cfg_port_member = ksz9477_cfg_port_member,
.port_setup = lan937x_port_setup,
+ .r_phy = lan937x_r_phy,
+ .w_phy = lan937x_w_phy,
.r_mib_cnt = ksz9477_r_mib_cnt,
.r_mib_pkt = ksz9477_r_mib_pkt,
.r_mib_stat64 = ksz_r_mib_stats64,
diff --git a/drivers/net/dsa/microchip/lan937x.h b/drivers/net/dsa/microchip/lan937x.h
index 534f5a7a1129..370203406a05 100644
--- a/drivers/net/dsa/microchip/lan937x.h
+++ b/drivers/net/dsa/microchip/lan937x.h
@@ -12,4 +12,6 @@ void lan937x_port_setup(struct ksz_device *dev, int port, bool cpu_port);
void lan937x_config_cpu_port(struct dsa_switch *ds);
int lan937x_switch_init(struct ksz_device *dev);
void lan937x_switch_exit(struct ksz_device *dev);
+void lan937x_r_phy(struct ksz_device *dev, u16 addr, u16 reg, u16 *data);
+void lan937x_w_phy(struct ksz_device *dev, u16 addr, u16 reg, u16 val);
#endif
diff --git a/drivers/net/dsa/microchip/lan937x_main.c b/drivers/net/dsa/microchip/lan937x_main.c
index e167a0c1ff85..5a2e14fe3cf3 100644
--- a/drivers/net/dsa/microchip/lan937x_main.c
+++ b/drivers/net/dsa/microchip/lan937x_main.c
@@ -28,6 +28,114 @@ static int lan937x_port_cfg(struct ksz_device *dev, int port, int offset,
bits, set ? bits : 0);
}

+static int lan937x_enable_spi_indirect_access(struct ksz_device *dev)
+{
+ u16 data16;
+ int ret;
+
+ /* Enable Phy access through SPI */
+ ret = lan937x_cfg(dev, REG_GLOBAL_CTRL_0, SW_PHY_REG_BLOCK, false);
+ if (ret < 0)
+ return ret;
+
+ ret = ksz_read16(dev, REG_VPHY_SPECIAL_CTRL__2, &data16);
+ if (ret < 0)
+ return ret;
+
+ /* Allow SPI access */
+ data16 |= VPHY_SPI_INDIRECT_ENABLE;
+
+ return ksz_write16(dev, REG_VPHY_SPECIAL_CTRL__2, data16);
+}
+
+static int lan937x_vphy_ind_addr_wr(struct ksz_device *dev, int addr, int reg)
+{
+ u16 addr_base = REG_PORT_T1_PHY_CTRL_BASE;
+ u16 temp;
+
+ /* get register address based on the logical port */
+ temp = PORT_CTRL_ADDR(addr, (addr_base + (reg << 2)));
+
+ return ksz_write16(dev, REG_VPHY_IND_ADDR__2, temp);
+}
+
+static int lan937x_internal_phy_write(struct ksz_device *dev, int addr, int reg,
+ u16 val)
+{
+ unsigned int value;
+ int ret;
+
+ /* Check for internal phy port */
+ if (!dev->info->internal_phy[addr])
+ return -EOPNOTSUPP;
+
+ ret = lan937x_vphy_ind_addr_wr(dev, addr, reg);
+ if (ret < 0)
+ return ret;
+
+ /* Write the data to be written to the VPHY reg */
+ ret = ksz_write16(dev, REG_VPHY_IND_DATA__2, val);
+ if (ret < 0)
+ return ret;
+
+ /* Write the Write En and Busy bit */
+ ret = ksz_write16(dev, REG_VPHY_IND_CTRL__2,
+ (VPHY_IND_WRITE | VPHY_IND_BUSY));
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read_poll_timeout(dev->regmap[1], REG_VPHY_IND_CTRL__2,
+ value, !(value & VPHY_IND_BUSY), 10,
+ 1000);
+ if (ret < 0) {
+ dev_err(dev->dev, "Failed to write phy register\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int lan937x_internal_phy_read(struct ksz_device *dev, int addr, int reg,
+ u16 *val)
+{
+ unsigned int value;
+ int ret;
+
+ /* Check for internal phy port, return 0xffff for non-existent phy */
+ if (!dev->info->internal_phy[addr])
+ return 0xffff;
+
+ ret = lan937x_vphy_ind_addr_wr(dev, addr, reg);
+ if (ret < 0)
+ return ret;
+
+ /* Write Read and Busy bit to start the transaction */
+ ret = ksz_write16(dev, REG_VPHY_IND_CTRL__2, VPHY_IND_BUSY);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read_poll_timeout(dev->regmap[1], REG_VPHY_IND_CTRL__2,
+ value, !(value & VPHY_IND_BUSY), 10,
+ 1000);
+ if (ret < 0) {
+ dev_err(dev->dev, "Failed to read phy register\n");
+ return ret;
+ }
+
+ /* Read the VPHY register which has the PHY data */
+ return ksz_read16(dev, REG_VPHY_IND_DATA__2, val);
+}
+
+void lan937x_r_phy(struct ksz_device *dev, u16 addr, u16 reg, u16 *data)
+{
+ lan937x_internal_phy_read(dev, addr, reg, data);
+}
+
+void lan937x_w_phy(struct ksz_device *dev, u16 addr, u16 reg, u16 val)
+{
+ lan937x_internal_phy_write(dev, addr, reg, val);
+}
+
int lan937x_reset_switch(struct ksz_device *dev)
{
u32 data32;
@@ -111,6 +219,14 @@ void lan937x_config_cpu_port(struct dsa_switch *ds)
int lan937x_setup(struct dsa_switch *ds)
{
struct ksz_device *dev = ds->priv;
+ int ret;
+
+ /* enable Indirect Access from SPI to the VPHY registers */
+ ret = lan937x_enable_spi_indirect_access(dev);
+ if (ret < 0) {
+ dev_err(dev->dev, "failed to enable spi indirect access");
+ return ret;
+ }

/* The VLAN aware is a global setting. Mixed vlan
* filterings are not supported.
diff --git a/drivers/net/dsa/microchip/lan937x_reg.h b/drivers/net/dsa/microchip/lan937x_reg.h
index 5e27b2bd2d86..7a0fa2595950 100644
--- a/drivers/net/dsa/microchip/lan937x_reg.h
+++ b/drivers/net/dsa/microchip/lan937x_reg.h
@@ -8,6 +8,12 @@
#define PORT_CTRL_ADDR(port, addr) ((addr) | (((port) + 1) << 12))

/* 0 - Operation */
+#define REG_GLOBAL_CTRL_0 0x0007
+
+#define SW_PHY_REG_BLOCK BIT(7)
+#define SW_FAST_MODE BIT(3)
+#define SW_FAST_MODE_OVERRIDE BIT(2)
+
#define REG_SW_INT_STATUS__4 0x0010
#define REG_SW_INT_MASK__4 0x0014

@@ -82,6 +88,33 @@
#define ALU_V_USE_FID BIT(30)
#define ALU_V_PORT_MAP 0xFF

+/* 7 - VPhy */
+#define REG_VPHY_IND_ADDR__2 0x075C
+#define REG_VPHY_IND_DATA__2 0x0760
+
+#define REG_VPHY_IND_CTRL__2 0x0768
+
+#define VPHY_IND_WRITE BIT(1)
+#define VPHY_IND_BUSY BIT(0)
+
+#define REG_VPHY_SPECIAL_CTRL__2 0x077C
+#define VPHY_SMI_INDIRECT_ENABLE BIT(15)
+#define VPHY_SW_LOOPBACK BIT(14)
+#define VPHY_MDIO_INTERNAL_ENABLE BIT(13)
+#define VPHY_SPI_INDIRECT_ENABLE BIT(12)
+#define VPHY_PORT_MODE_M 0x3
+#define VPHY_PORT_MODE_S 8
+#define VPHY_MODE_RGMII 0
+#define VPHY_MODE_MII_PHY 1
+#define VPHY_MODE_SGMII 2
+#define VPHY_MODE_RMII_PHY 3
+#define VPHY_SW_COLLISION_TEST BIT(7)
+#define VPHY_SPEED_DUPLEX_STAT_M 0x7
+#define VPHY_SPEED_DUPLEX_STAT_S 2
+#define VPHY_SPEED_1000 BIT(4)
+#define VPHY_SPEED_100 BIT(3)
+#define VPHY_FULL_DUPLEX BIT(2)
+
/* Port Registers */

/* 0 - Operation */
@@ -94,6 +127,9 @@
#define PORT_TAIL_TAG_ENABLE BIT(2)
#define PORT_QUEUE_SPLIT_ENABLE 0x3

+/* 1 - Phy */
+#define REG_PORT_T1_PHY_CTRL_BASE 0x0100
+
/* 3 - xMII */
#define REG_PORT_XMII_CTRL_0 0x0300
#define PORT_SGMII_SEL BIT(7)
--
2.36.1