RE: [PATCH v1 4/6] net/axgbe: reset PHY Rx when mailbox command timeout

["Namburu, Chandu-babu" <chandu@amd.com>]

[Public]

Acked-by: Chandubabu Namburu <chandu@amd.com>

-----Original Message-----
From: ssebasti@amd.com <ssebasti@amd.com> 
Sent: Monday, January 10, 2022 5:05 PM
To: dev@dpdk.org
Subject: [PATCH v1 4/6] net/axgbe: reset PHY Rx when mailbox command timeout

From: Selwin Sebastian <selwin.sebastian@amd.com>

Sometimes mailbox commands timeout when the RX data path becomes unresponsive. This prevents the submission of new mailbox commands to DXIO. This patch identifies the timeout and resets the RX data path so that the next message can be submitted properly.

Signed-off-by: Selwin Sebastian <selwin.sebastian@amd.com>
---
 drivers/net/axgbe/axgbe_common.h   | 14 ++++++++++++++
 drivers/net/axgbe/axgbe_phy_impl.c | 29 ++++++++++++++++++++++++++++-
 2 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/drivers/net/axgbe/axgbe_common.h b/drivers/net/axgbe/axgbe_common.h
index 5a7ac35b6a..a5431dd998 100644
--- a/drivers/net/axgbe/axgbe_common.h
+++ b/drivers/net/axgbe/axgbe_common.h
@@ -1270,10 +1270,18 @@
 #define MDIO_PMA_10GBR_FECCTRL		0x00ab
 #endif
 
+#ifndef MDIO_PMA_RX_CTRL1
+#define MDIO_PMA_RX_CTRL1		0x8051
+#endif
+
 #ifndef MDIO_PCS_DIG_CTRL
 #define MDIO_PCS_DIG_CTRL		0x8000
 #endif
 
+#ifndef MDIO_PCS_DIGITAL_STAT
+#define MDIO_PCS_DIGITAL_STAT		0x8010
+#endif
+
 #ifndef MDIO_AN_XNP
 #define MDIO_AN_XNP			0x0016
 #endif
@@ -1354,6 +1362,8 @@
 #define AXGBE_KR_TRAINING_ENABLE	BIT(1)
 
 #define AXGBE_PCS_CL37_BP		BIT(12)
+#define XGBE_PCS_PSEQ_STATE_MASK	0x1c
+#define XGBE_PCS_PSEQ_STATE_POWER_GOOD	0x10
 
 #define AXGBE_AN_CL37_INT_CMPLT		BIT(0)
 #define AXGBE_AN_CL37_INT_MASK		0x01
@@ -1401,6 +1411,10 @@ static inline uint32_t high32_value(uint64_t addr)
 #define XGBE_PMA_PLL_CTRL_SET          BIT(15)
 #define XGBE_PMA_PLL_CTRL_CLEAR                0x0000
 
+#define XGBE_PMA_RX_RST_0_MASK         BIT(4)
+#define XGBE_PMA_RX_RST_0_RESET_ON     0x10
+#define XGBE_PMA_RX_RST_0_RESET_OFF    0x00
+
 /*END*/
 
 /* Bit setting and getting macros
diff --git a/drivers/net/axgbe/axgbe_phy_impl.c b/drivers/net/axgbe/axgbe_phy_impl.c
index 0894dbf74b..e52dbb9585 100644
--- a/drivers/net/axgbe/axgbe_phy_impl.c
+++ b/drivers/net/axgbe/axgbe_phy_impl.c
@@ -1196,6 +1196,28 @@ static void axgbe_phy_set_redrv_mode(struct axgbe_port *pdata)
 	axgbe_phy_put_comm_ownership(pdata);
 }
 
+static void axgbe_phy_rx_reset(struct axgbe_port *pdata) {
+	int reg;
+
+	reg = XMDIO_READ_BITS(pdata, MDIO_MMD_PCS, MDIO_PCS_DIGITAL_STAT,
+			      XGBE_PCS_PSEQ_STATE_MASK);
+	if (reg == XGBE_PCS_PSEQ_STATE_POWER_GOOD) {
+		/* Mailbox command timed out, reset of RX block is required.
+		 * This can be done by asseting the reset bit and wait for
+		 * its compeletion.
+		 */
+		XMDIO_WRITE_BITS(pdata, MDIO_MMD_PMAPMD, MDIO_PMA_RX_CTRL1,
+				 XGBE_PMA_RX_RST_0_MASK, XGBE_PMA_RX_RST_0_RESET_ON);
+		rte_delay_us(20);
+		XMDIO_WRITE_BITS(pdata, MDIO_MMD_PMAPMD, MDIO_PMA_RX_CTRL1,
+				 XGBE_PMA_RX_RST_0_MASK, XGBE_PMA_RX_RST_0_RESET_OFF);
+		rte_delay_us(45);
+		PMD_DRV_LOG(ERR, "firmware mailbox reset performed\n");
+	}
+}
+
+
 static void axgbe_phy_pll_ctrl(struct axgbe_port *pdata, bool enable)  {
 	XMDIO_WRITE_BITS(pdata, MDIO_MMD_PMAPMD, MDIO_VEND2_PMA_MISC_CTRL0, @@ -1216,8 +1238,10 @@ static void axgbe_phy_perform_ratechange(struct axgbe_port *pdata,
 	axgbe_phy_pll_ctrl(pdata, false);
 
 	/* Log if a previous command did not complete */
-	if (XP_IOREAD_BITS(pdata, XP_DRIVER_INT_RO, STATUS))
+	if (XP_IOREAD_BITS(pdata, XP_DRIVER_INT_RO, STATUS)) {
 		PMD_DRV_LOG(NOTICE, "firmware mailbox not ready for command\n");
+		axgbe_phy_rx_reset(pdata);
+	}
 
 	/* Construct the command */
 	XP_SET_BITS(s0, XP_DRIVER_SCRATCH_0, COMMAND, cmd); @@ -1235,6 +1259,9 @@ static void axgbe_phy_perform_ratechange(struct axgbe_port *pdata,
 			goto reenable_pll;
 		rte_delay_us(1500);
 	}
+	PMD_DRV_LOG(NOTICE, "firmware mailbox command did not complete\n");
+	/* Reset on error */
+	axgbe_phy_rx_reset(pdata);
 
 reenable_pll:
 	 /* Re-enable the PLL control */
--
2.25.1