amd-xgbe: TX Flow Ctrl Registers are h/w ver dependent

stable inclusion
from stable-v5.10.166
commit a65a8727a2fe606036933222313c775964de6e92
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7TH9O

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a65a8727a2fe606036933222313c775964de6e92

--------------------------------

[ Upstream commit 579923d8 ]

There is difference in the TX Flow Control registers (TFCR) between the
revisions of the hardware. The older revisions of hardware used to have
single register per queue. Whereas, the newer revision of hardware (from
ver 30H onwards) have one register per priority.

Update the driver to use the TFCR based on the reported version of the
hardware.

Fixes: c5aa9e3b ("amd-xgbe: Initial AMD 10GbE platform driver")
Co-developed-by: NAjith Nayak <Ajith.Nayak@amd.com>
Signed-off-by: NAjith Nayak <Ajith.Nayak@amd.com>
Signed-off-by: NRaju Rangoju <Raju.Rangoju@amd.com>
Acked-by: NShyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: Nsanglipeng <sanglipeng1@jd.com>

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);