[PATCH net-next v4 3/8] net: dsa: motorcomm: Identify port type at runtime

[David Yang <mmyangfl@gmail.com>]

The yt921x_port_is_internal/external() macros hardcoded the port layout:
they treat ports 8 and 9 as external on every chip and count the dummy
ports as internal.

Identify the actual port capabilities using chip info and track
configuration of external ports (although only SerDes is supported now).
This is a hardening and cleanup step ahead of the SerDes PCS support, no
behavior changes intended.

Signed-off-by: David Yang <mmyangfl@gmail.com>
---
 drivers/net/dsa/motorcomm/chip.c | 40 +++++++++++++++++++++++---------
 drivers/net/dsa/motorcomm/chip.h | 11 +++++----
 2 files changed, 35 insertions(+), 16 deletions(-)

diff --git a/drivers/net/dsa/motorcomm/chip.c b/drivers/net/dsa/motorcomm/chip.c
index 54881856b796..ea4b29882b5c 100644
--- a/drivers/net/dsa/motorcomm/chip.c
+++ b/drivers/net/dsa/motorcomm/chip.c
@@ -3738,6 +3738,7 @@ yt921x_dsa_port_set_apptrust(struct dsa_switch *ds, int port, const u8 *sel,
 
 static int yt921x_port_down(struct yt921x_priv *priv, int port)
 {
+	const struct yt921x_info *info = priv->info;
 	u32 mask;
 	int res;
 
@@ -3746,12 +3747,13 @@ static int yt921x_port_down(struct yt921x_priv *priv, int port)
 	if (res)
 		return res;
 
-	if (yt921x_port_is_external(port)) {
+	if (BIT(port) & info->serdes_mask) {
 		mask = YT921X_SERDES_LINK;
 		res = yt921x_reg_clear_bits(priv, YT921X_SERDESn(port), mask);
 		if (res)
 			return res;
-
+	}
+	if (BIT(port) & info->xmii_mask) {
 		mask = YT921X_XMII_LINK;
 		res = yt921x_reg_clear_bits(priv, YT921X_XMIIn(port), mask);
 		if (res)
@@ -3766,6 +3768,8 @@ yt921x_port_up(struct yt921x_priv *priv, int port, unsigned int mode,
 	       phy_interface_t interface, int speed, int duplex,
 	       bool tx_pause, bool rx_pause)
 {
+	const struct yt921x_info *info = priv->info;
+	struct yt921x_port *pp = &priv->ports[port];
 	u32 mask;
 	u32 ctrl;
 	int res;
@@ -3800,7 +3804,10 @@ yt921x_port_up(struct yt921x_priv *priv, int port, unsigned int mode,
 	if (res)
 		return res;
 
-	if (yt921x_port_is_external(port)) {
+	if (!(BIT(port) & (info->serdes_mask | info->xmii_mask)))
+		return 0;
+
+	if (pp->serdes) {
 		mask = YT921X_SERDES_SPEED_M;
 		switch (speed) {
 		case SPEED_10:
@@ -3836,7 +3843,7 @@ yt921x_port_up(struct yt921x_priv *priv, int port, unsigned int mode,
 					     mask, ctrl);
 		if (res)
 			return res;
-
+	} else {
 		mask = YT921X_XMII_LINK;
 		res = yt921x_reg_set_bits(priv, YT921X_XMIIn(port), mask);
 		if (res)
@@ -3876,17 +3883,16 @@ static int
 yt921x_port_config(struct yt921x_priv *priv, int port, unsigned int mode,
 		   phy_interface_t interface)
 {
+	const struct yt921x_info *info = priv->info;
+	struct yt921x_port *pp = &priv->ports[port];
 	struct device *dev = to_device(priv);
 	u32 mask;
 	u32 ctrl;
 	int res;
 
-	if (!yt921x_port_is_external(port)) {
-		if (interface != PHY_INTERFACE_MODE_INTERNAL) {
-			dev_err(dev, "Wrong mode %d on port %d\n",
-				interface, port);
-			return -EINVAL;
-		}
+	if (BIT(port) & info->internal_mask) {
+		if (interface != PHY_INTERFACE_MODE_INTERNAL)
+			goto err;
 		return 0;
 	}
 
@@ -3896,6 +3902,9 @@ yt921x_port_config(struct yt921x_priv *priv, int port, unsigned int mode,
 	case PHY_INTERFACE_MODE_100BASEX:
 	case PHY_INTERFACE_MODE_1000BASEX:
 	case PHY_INTERFACE_MODE_2500BASEX:
+		if (!(BIT(port) & info->serdes_mask))
+			goto err;
+
 		mask = YT921X_SERDES_CTRL_PORTn(port);
 		res = yt921x_reg_set_bits(priv, YT921X_SERDES_CTRL, mask);
 		if (res)
@@ -3906,6 +3915,11 @@ yt921x_port_config(struct yt921x_priv *priv, int port, unsigned int mode,
 		if (res)
 			return res;
 
+		/* The order is quite arbitrary - we can't return to a safe
+		 * state on IO errors.
+		 */
+		pp->serdes = true;
+
 		mask = YT921X_SERDES_MODE_M;
 		switch (interface) {
 		case PHY_INTERFACE_MODE_SGMII:
@@ -3931,10 +3945,14 @@ yt921x_port_config(struct yt921x_priv *priv, int port, unsigned int mode,
 		break;
 	/* add XMII support here */
 	default:
-		return -EINVAL;
+		goto err;
 	}
 
 	return 0;
+
+err:
+	dev_err(dev, "Wrong mode %d on port %d\n", interface, port);
+	return -EINVAL;
 }
 
 static void
diff --git a/drivers/net/dsa/motorcomm/chip.h b/drivers/net/dsa/motorcomm/chip.h
index 83e76cefbccd..fd552f7dced4 100644
--- a/drivers/net/dsa/motorcomm/chip.h
+++ b/drivers/net/dsa/motorcomm/chip.h
@@ -858,9 +858,6 @@ enum yt921x_fdb_entry_status {
 
 #define YT921X_NAME	"yt921x"
 
-#define yt921x_port_is_internal(port) ((port) < 8)
-#define yt921x_port_is_external(port) ((port) == 8 || (port) == 9)
-
 struct yt921x_mib {
 	u64 rx_broadcast;
 	u64 rx_pause;
@@ -936,8 +933,12 @@ struct yt921x_acl_blk {
 struct yt921x_port {
 	unsigned char index;
 
-	bool hairpin;
-	bool isolated;
+	/* SerDes in use */
+	bool serdes:1;
+	/* BR_HAIRPIN_MODE */
+	bool hairpin:1;
+	/* BR_ISOLATED */
+	bool isolated:1;
 
 	struct delayed_work mib_read;
 	struct yt921x_mib mib;
-- 
2.53.0