net: phy: qcom: Add PHY counter support

Add PHY counter functionality to the shared library. The implementation
is identical for the current QCA807X and QCA808X PHYs.

The PHY counter can be configured to perform CRC checking for both received
and transmitted packets. Additionally, the packet counter can be set to
automatically clear after it is read.

The PHY counter includes 32-bit packet counters for both RX (received) and
TX (transmitted) packets, as well as 16-bit counters for recording CRC
error packets for both RX and TX.

Signed-off-by: Luo Jie <[e-mail]>
Reviewed-by: Andrew Lunn <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/phy/qcom/qcom-phy-lib.c

···
 	return 0;
 }
 EXPORT_SYMBOL_GPL(qca808x_led_reg_blink_set);
+
+/* Enable CRC checking for both received and transmitted frames to ensure
+ * accurate counter recording. The hardware supports a 32-bit counter,
+ * configure the counter to clear after it is read to facilitate the
+ * implementation of a 64-bit software counter
+ */
+int qcom_phy_counter_config(struct phy_device *phydev)
+{
+	return phy_set_bits_mmd(phydev, MDIO_MMD_AN, QCA808X_MMD7_CNT_CTRL,
+				QCA808X_MMD7_CNT_CTRL_CRC_CHECK_EN |
+				QCA808X_MMD7_CNT_CTRL_READ_CLEAR_EN);
+}
+EXPORT_SYMBOL_GPL(qcom_phy_counter_config);
+
+int qcom_phy_update_stats(struct phy_device *phydev,
+			  struct qcom_phy_hw_stats *hw_stats)
+{
+	int ret;
+	u32 cnt;
+
+	/* PHY 32-bit counter for RX packets. */
+	ret = phy_read_mmd(phydev, MDIO_MMD_AN, QCA808X_MMD7_CNT_RX_PKT_15_0);
+	if (ret < 0)
+		return ret;
+
+	cnt = ret;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_AN, QCA808X_MMD7_CNT_RX_PKT_31_16);
+	if (ret < 0)
+		return ret;
+
+	cnt |= ret << 16;
+	hw_stats->rx_pkts += cnt;
+
+	/* PHY 16-bit counter for RX CRC error packets. */
+	ret = phy_read_mmd(phydev, MDIO_MMD_AN, QCA808X_MMD7_CNT_RX_ERR_PKT);
+	if (ret < 0)
+		return ret;
+
+	hw_stats->rx_err_pkts += ret;
+
+	/* PHY 32-bit counter for TX packets. */
+	ret = phy_read_mmd(phydev, MDIO_MMD_AN, QCA808X_MMD7_CNT_TX_PKT_15_0);
+	if (ret < 0)
+		return ret;
+
+	cnt = ret;
+
+	ret = phy_read_mmd(phydev, MDIO_MMD_AN, QCA808X_MMD7_CNT_TX_PKT_31_16);
+	if (ret < 0)
+		return ret;
+
+	cnt |= ret << 16;
+	hw_stats->tx_pkts += cnt;
+
+	/* PHY 16-bit counter for TX CRC error packets. */
+	ret = phy_read_mmd(phydev, MDIO_MMD_AN, QCA808X_MMD7_CNT_TX_ERR_PKT);
+	if (ret < 0)
+		return ret;
+
+	hw_stats->tx_err_pkts += ret;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_phy_update_stats);
+
+void qcom_phy_get_stats(struct ethtool_phy_stats *stats,
+			struct qcom_phy_hw_stats hw_stats)
+{
+	stats->tx_packets = hw_stats.tx_pkts;
+	stats->tx_errors = hw_stats.tx_err_pkts;
+	stats->rx_packets = hw_stats.rx_pkts;
+	stats->rx_errors = hw_stats.rx_err_pkts;
+}
+EXPORT_SYMBOL_GPL(qcom_phy_get_stats);

drivers/net/phy/qcom/qcom.h

···
 #define AT803X_MIN_DOWNSHIFT			2
 #define AT803X_MAX_DOWNSHIFT			9
 
+#define QCA808X_MMD7_CNT_CTRL			0x8029
+#define QCA808X_MMD7_CNT_CTRL_READ_CLEAR_EN	BIT(1)
+#define QCA808X_MMD7_CNT_CTRL_CRC_CHECK_EN	BIT(0)
+
+#define QCA808X_MMD7_CNT_RX_PKT_31_16		0x802a
+#define QCA808X_MMD7_CNT_RX_PKT_15_0		0x802b
+#define QCA808X_MMD7_CNT_RX_ERR_PKT		0x802c
+#define QCA808X_MMD7_CNT_TX_PKT_31_16		0x802d
+#define QCA808X_MMD7_CNT_TX_PKT_15_0		0x802e
+#define QCA808X_MMD7_CNT_TX_ERR_PKT		0x802f
+
 enum stat_access_type {
 	PHY,
 	MMD
···
 struct at803x_ss_mask {
 	u16 speed_mask;
 	u8 speed_shift;
+};
+
+struct qcom_phy_hw_stats {
+	u64 rx_pkts;
+	u64 rx_err_pkts;
+	u64 tx_pkts;
+	u64 tx_err_pkts;
 };
 
 int at803x_debug_reg_read(struct phy_device *phydev, u16 reg);
···
 int qca808x_led_reg_blink_set(struct phy_device *phydev, u16 reg,
 			      unsigned long *delay_on,
 			      unsigned long *delay_off);
+int qcom_phy_counter_config(struct phy_device *phydev);
+int qcom_phy_update_stats(struct phy_device *phydev,
+			  struct qcom_phy_hw_stats *hw_stats);
+void qcom_phy_get_stats(struct ethtool_phy_stats *stats,
+			struct qcom_phy_hw_stats hw_stats);