realtek: dsa: move egress rate handling to SoC config

The RTL838x and RTL839x families use different mechanisms for reading
and configuring the port egress rate.

Add get_egress_rate and set_egress_rate callbacks to rtldsa_config and
use them from debugfs instead of selecting the implementation based on
priv->family_id.

Rename the existing functions to use the rtldsa_838x and rtldsa_839x
prefixes consistently with the other SoC-specific callbacks.

This removes another family_id dependency from the common debugfs
code and keeps the SoC-specific implementation selected through
rtldsa_config.

While we are here do some minor type cleanups:

- Change the value used by port_egress_rate_read() from int to u32
  and remove the negative value check. Both get_egress_rate callbacks
  return u32, so value can never be negative and the check could not
  report an error. The callbacks return 0 for an invalid port instead.
- Change the res size_t variable type to ssize_t. This fixes the dead
  comparison "res < 0".
- Remove the uninitialized read in rtldsa_839x_get_egress_rate()

Assisted-by: ChatGPT (OpenAI GPT-5.6 Sol)
Link: https://github.com/openwrt/openwrt/pull/24918
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>

target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/debugfs.c

@@ -632,17 +632,11 @@ static ssize_t port_egress_rate_read(struct file *filp, char __user *buffer, siz
 	struct rtldsa_port *p = filp->private_data;
 	struct dsa_switch *ds = p->dp->ds;
 	struct rtl838x_switch_priv *priv = ds->priv;
-	int value;
+	u32 value;
 
-	if (priv->family_id == RTL8380_FAMILY_ID)
-		value = rtl838x_get_egress_rate(priv, p->dp->index);
-	else
-		value = rtl839x_get_egress_rate(priv, p->dp->index);
+	value = priv->r->get_egress_rate(priv, p->dp->index);
 
-	if (value < 0)
-		return -EINVAL;
-
-	return rtl838x_common_read(buffer, count, ppos, (u32)value);
+	return rtl838x_common_read(buffer, count, ppos, value);
 }
 
 static ssize_t port_egress_rate_write(struct file *filp, const char __user *buffer,
@@ -652,15 +646,13 @@ static ssize_t port_egress_rate_write(struct file *filp, const char __user *buff
 	struct dsa_switch *ds = p->dp->ds;
 	struct rtl838x_switch_priv *priv = ds->priv;
 	u32 value;
-	size_t res = rtl838x_common_write(buffer, count, ppos, &value);
+	ssize_t res;
 
+	res = rtl838x_common_write(buffer, count, ppos, &value);
 	if (res < 0)
 		return res;
 
-	if (priv->family_id == RTL8380_FAMILY_ID)
-		rtl838x_set_egress_rate(priv, p->dp->index, value);
-	else
-		rtl839x_set_egress_rate(priv, p->dp->index, value);
+	priv->r->set_egress_rate(priv, p->dp->index, value);
 
 	return res;
 }

target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/qos.c

@@ -42,7 +42,7 @@ static void rtl839x_read_out_q_table(int port)
 	rtl839x_exec_tbl2_cmd(cmd);
 }
 
-u32 rtl838x_get_egress_rate(struct rtl838x_switch_priv *priv, int port)
+u32 rtldsa_838x_get_egress_rate(struct rtl838x_switch_priv *priv, int port)
 {
 	if (port > priv->r->cpu_port)
 		return 0;
@@ -51,7 +51,7 @@ u32 rtl838x_get_egress_rate(struct rtl838x_switch_priv *priv, int port)
 }
 
 /* Sets the rate limit, 10MBit/s is equal to a rate value of 625 */
-int rtl838x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate)
+int rtldsa_838x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate)
 {
 	u32 old_rate;
 
@@ -65,11 +65,10 @@ int rtl838x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate
 }
 
 /* Sets the rate limit, 10MBit/s is equal to a rate value of 625 */
-u32 rtl839x_get_egress_rate(struct rtl838x_switch_priv *priv, int port)
+u32 rtldsa_839x_get_egress_rate(struct rtl838x_switch_priv *priv, int port)
 {
 	u32 rate;
 
-	pr_debug("%s: Getting egress rate on port %d to %d\n", __func__, port, rate);
 	if (port >= priv->r->cpu_port)
 		return 0;
 
@@ -82,12 +81,13 @@ u32 rtl839x_get_egress_rate(struct rtl838x_switch_priv *priv, int port)
 	rate |= sw_r32(RTL839X_TBL_ACCESS_DATA_2(8)) >> 20;
 
 	mutex_unlock(&priv->reg_mutex);
+	pr_debug("%s: Getting egress rate on port %d is %d\n", __func__, port, rate);
 
 	return rate;
 }
 
 /* Sets the rate limit, 10MBit/s is equal to a rate value of 625, returns previous rate */
-int rtl839x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate)
+int rtldsa_839x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate)
 {
 	u32 old_rate;
 
@@ -212,7 +212,7 @@ static void rtl839x_set_scheduling_algorithm(struct rtl838x_switch_priv *priv, i
 		sw_w32(0x2, RTL839X_OAM_PORT_ACT_CTRL(port));
 
 		/* Set port egress rate to unlimited */
-		egress_rate = rtl839x_set_egress_rate(priv, port, 0xFFFFF);
+		egress_rate = rtldsa_839x_set_egress_rate(priv, port, 0xFFFFF);
 
 		/* Wait until the egress used page count of that port is 0 */
 		i = 0;
@@ -238,7 +238,7 @@ static void rtl839x_set_scheduling_algorithm(struct rtl838x_switch_priv *priv, i
 		sw_w32(oam_port_state, RTL839X_OAM_PORT_ACT_CTRL(port));
 
 		/* Restore port egress rate */
-		rtl839x_set_egress_rate(priv, port, egress_rate);
+		rtldsa_839x_set_egress_rate(priv, port, egress_rate);
 	}
 
 	mutex_unlock(&priv->reg_mutex);

target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/rtl-otto.h

@@ -1415,6 +1415,8 @@ struct rtldsa_config {
 	void (*packet_cntr_clear)(int counter);
 	void (*set_receive_management_action)(int port, rma_ctrl_t type, action_type_t action);
 	void (*led_init)(struct rtl838x_switch_priv *priv);
+	u32 (*get_egress_rate)(struct rtl838x_switch_priv *priv, int port);
+	int (*set_egress_rate)(struct rtl838x_switch_priv *priv, int port, u32 rate);
 	void (*qos_init)(struct rtl838x_switch_priv *priv);
 	int (*trk_mbr_ctr)(int group);
 	void (*lag_switch_init)(struct rtl838x_switch_priv *priv);
@@ -1628,20 +1630,20 @@ int rtl83xx_setup_tc(struct net_device *dev, enum tc_setup_type type, void *type
 
 /* Port register accessor functions for the RTL839x and RTL931X SoCs */
 void rtl839x_mask_port_reg_be(u64 clear, u64 set, int reg);
-u32 rtl839x_get_egress_rate(struct rtl838x_switch_priv *priv, int port);
+u32 rtldsa_839x_get_egress_rate(struct rtl838x_switch_priv *priv, int port);
 u64 rtl839x_get_port_reg_be(int reg);
 void rtl839x_set_port_reg_be(u64 set, int reg);
 void rtl839x_mask_port_reg_le(u64 clear, u64 set, int reg);
-int rtl839x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate);
+int rtldsa_839x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate);
 void rtl839x_set_port_reg_le(u64 set, int reg);
 u64 rtl839x_get_port_reg_le(int reg);
 
 /* Port register accessor functions for the RTL838x and RTL930X SoCs */
 void rtl838x_mask_port_reg(u64 clear, u64 set, int reg);
 void rtl838x_set_port_reg(u64 set, int reg);
-u32 rtl838x_get_egress_rate(struct rtl838x_switch_priv *priv, int port);
+u32 rtldsa_838x_get_egress_rate(struct rtl838x_switch_priv *priv, int port);
 u64 rtl838x_get_port_reg(int reg);
-int rtl838x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate);
+int rtldsa_838x_set_egress_rate(struct rtl838x_switch_priv *priv, int port, u32 rate);
 
 /* RTL838x-specific */
 u32 rtl838x_hash(struct rtl838x_switch_priv *priv, u64 seed);

target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/rtl838x.c

@@ -1851,6 +1851,8 @@ const struct rtldsa_config rtldsa_838x_cfg = {
 	.packet_cntr_read = rtl838x_packet_cntr_read,
 	.packet_cntr_clear = rtl838x_packet_cntr_clear,
 	.set_receive_management_action = rtl838x_set_receive_management_action,
+	.get_egress_rate = rtldsa_838x_get_egress_rate,
+	.set_egress_rate = rtldsa_838x_set_egress_rate,
 	.qos_init = rtldsa_838x_qos_init,
 	.lag_set_distribution_algorithm = rtldsa_838x_set_distribution_algorithm,
 	.lag_set_port_members = rtldsa_838x_lag_set_port_members,

target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/rtl839x.c

@@ -1734,6 +1734,8 @@ const struct rtldsa_config rtldsa_839x_cfg = {
 	.packet_cntr_read = rtl839x_packet_cntr_read,
 	.packet_cntr_clear = rtl839x_packet_cntr_clear,
 	.set_receive_management_action = rtl839x_set_receive_management_action,
+	.get_egress_rate = rtldsa_839x_get_egress_rate,
+	.set_egress_rate = rtldsa_839x_set_egress_rate,
 	.qos_init = rtldsa_839x_qos_init,
 	.lag_set_distribution_algorithm = rtldsa_839x_set_distribution_algorithm,
 	.lag_set_port_members = rtldsa_839x_lag_set_port_members,