Merge branch 'amd-xgbe-pfc-and-kr-training-fixes'

Raju Rangoju says:

====================
amd-xgbe: PFC and KR-Training fixes

This patch series fixes the issues in kr-training and pfc

0001 - There is difference in the TX Flow Control registers (TFCR)
between the revisions of the hardware. Update the driver to use the
TFCR based on the reported version of the hardware.

0002 - AN restart triggered during KR training not only aborts the KR
training process but also move the HW to unstable state. Add the
necessary changes to fix kr-taining.
====================

Link: https://lore.kernel.org/r/20230111172852.1875384-1-Raju.Rangoju@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 41 insertions, 8 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
index 3936543a74d8..4030d619e84f 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
@@ -524,19 +524,28 @@ static void xgbe_disable_vxlan(struct xgbe_prv_data *pdata)
 	netif_dbg(pdata, drv, pdata->netdev, "VXLAN acceleration disabled\n");
 }
 
+static unsigned int xgbe_get_fc_queue_count(struct xgbe_prv_data *pdata)
+{
+	unsigned int max_q_count = XGMAC_MAX_FLOW_CONTROL_QUEUES;
+
+	/* From MAC ver 30H the TFCR is per priority, instead of per queue */
+	if (XGMAC_GET_BITS(pdata->hw_feat.version, MAC_VR, SNPSVER) >= 0x30)
+		return max_q_count;
+	else
+		return min_t(unsigned int, pdata->tx_q_count, max_q_count);
+}
+
 static int xgbe_disable_tx_flow_control(struct xgbe_prv_data *pdata)
 {
-	unsigned int max_q_count, q_count;
 	unsigned int reg, reg_val;
-	unsigned int i;
+	unsigned int i, q_count;
 
 	/* Clear MTL flow control */
 	for (i = 0; i < pdata->rx_q_count; i++)
 		XGMAC_MTL_IOWRITE_BITS(pdata, i, MTL_Q_RQOMR, EHFC, 0);
 
 	/* Clear MAC flow control */
-	max_q_count = XGMAC_MAX_FLOW_CONTROL_QUEUES;
-	q_count = min_t(unsigned int, pdata->tx_q_count, max_q_count);
+	q_count = xgbe_get_fc_queue_count(pdata);
 	reg = MAC_Q0TFCR;
 	for (i = 0; i < q_count; i++) {
 		reg_val = XGMAC_IOREAD(pdata, reg);
@@ -553,9 +562,8 @@ static int xgbe_enable_tx_flow_control(struct xgbe_prv_data *pdata)
 {
 	struct ieee_pfc *pfc = pdata->pfc;
 	struct ieee_ets *ets = pdata->ets;
-	unsigned int max_q_count, q_count;
 	unsigned int reg, reg_val;
-	unsigned int i;
+	unsigned int i, q_count;
 
 	/* Set MTL flow control */
 	for (i = 0; i < pdata->rx_q_count; i++) {
@@ -579,8 +587,7 @@ static int xgbe_enable_tx_flow_control(struct xgbe_prv_data *pdata)
 	}
 
 	/* Set MAC flow control */
-	max_q_count = XGMAC_MAX_FLOW_CONTROL_QUEUES;
-	q_count = min_t(unsigned int, pdata->tx_q_count, max_q_count);
+	q_count = xgbe_get_fc_queue_count(pdata);
 	reg = MAC_Q0TFCR;
 	for (i = 0; i < q_count; i++) {
 		reg_val = XGMAC_IOREAD(pdata, reg);
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c b/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
index 0c5c1b155683..43fdd111235a 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
@@ -496,6 +496,7 @@ static enum xgbe_an xgbe_an73_tx_training(struct xgbe_prv_data *pdata,
 	reg |= XGBE_KR_TRAINING_ENABLE;
 	reg |= XGBE_KR_TRAINING_START;
 	XMDIO_WRITE(pdata, MDIO_MMD_PMAPMD, MDIO_PMA_10GBR_PMD_CTRL, reg);
+	pdata->kr_start_time = jiffies;
 
 	netif_dbg(pdata, link, pdata->netdev,
 		  "KR training initiated\n");
@@ -632,6 +633,8 @@ static enum xgbe_an xgbe_an73_incompat_link(struct xgbe_prv_data *pdata)
 
 	xgbe_switch_mode(pdata);
 
+	pdata->an_result = XGBE_AN_READY;
+
 	xgbe_an_restart(pdata);
 
 	return XGBE_AN_INCOMPAT_LINK;
@@ -1275,9 +1278,30 @@ static bool xgbe_phy_aneg_done(struct xgbe_prv_data *pdata)
 static void xgbe_check_link_timeout(struct xgbe_prv_data *pdata)
 {
 	unsigned long link_timeout;
+	unsigned long kr_time;
+	int wait;
 
 	link_timeout = pdata->link_check + (XGBE_LINK_TIMEOUT * HZ);
 	if (time_after(jiffies, link_timeout)) {
+		if ((xgbe_cur_mode(pdata) == XGBE_MODE_KR) &&
+		    pdata->phy.autoneg == AUTONEG_ENABLE) {
+			/* AN restart should not happen while KR training is in progress.
+			 * The while loop ensures no AN restart during KR training,
+			 * waits up to 500ms and AN restart is triggered only if KR
+			 * training is failed.
+			 */
+			wait = XGBE_KR_TRAINING_WAIT_ITER;
+			while (wait--) {
+				kr_time = pdata->kr_start_time +
+					  msecs_to_jiffies(XGBE_AN_MS_TIMEOUT);
+				if (time_after(jiffies, kr_time))
+					break;
+				/* AN restart is not required, if AN result is COMPLETE */
+				if (pdata->an_result == XGBE_AN_COMPLETE)
+					return;
+				usleep_range(10000, 11000);
+			}
+		}
 		netif_dbg(pdata, link, pdata->netdev, "AN link timeout\n");
 		xgbe_phy_config_aneg(pdata);
 	}
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index 71f24cb47935..7a41367c437d 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -290,6 +290,7 @@
 /* Auto-negotiation */
 #define XGBE_AN_MS_TIMEOUT		500
 #define XGBE_LINK_TIMEOUT		5
+#define XGBE_KR_TRAINING_WAIT_ITER	50
 
 #define XGBE_SGMII_AN_LINK_STATUS	BIT(1)
 #define XGBE_SGMII_AN_LINK_SPEED	(BIT(2) | BIT(3))
@@ -1280,6 +1281,7 @@ struct xgbe_prv_data {
 	unsigned int parallel_detect;
 	unsigned int fec_ability;
 	unsigned long an_start;
+	unsigned long kr_start_time;
 	enum xgbe_an_mode an_mode;
 
 	/* I2C support */