[PATCH net-next 25/30] net: dsa: mt7530: properly set MT7531_CPU_PMAP

[arinc9.unal at gmail.com]

From: Arınç ÜNAL <arinc.unal at arinc9.com>

Every bit of the CPU port bitmap for MT7531 and the switch on the MT7988
SoC represents a CPU port to trap frames to. Currently only the bit that
corresponds to the first found CPU port is set on the bitmap. Introduce the
MT7531_CPU_PMAP macro to individually set the bits of the CPU port bitmap.
Set the CPU port bitmap for MT7531 and the switch on the MT7988 SoC on
mt753x_cpu_port_enable() which runs on a loop for each CPU port. Add
comments to explain this.

According to the document MT7531 Reference Manual for Development Board
v1.0, the MT7531_CPU_PMAP bits are unset after reset so no need to clear it
beforehand. Since there's currently no public document for the switch on
the MT7988 SoC, I assume this is also the case for this switch.

Tested-by: Arınç ÜNAL <arinc.unal at arinc9.com>
Signed-off-by: Arınç ÜNAL <arinc.unal at arinc9.com>
---
 drivers/net/dsa/mt7530.c | 15 ++++++++-------
 drivers/net/dsa/mt7530.h |  3 ++-
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 58d8738d94d3..0b513e3628fe 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -963,6 +963,13 @@ mt753x_cpu_port_enable(struct dsa_switch *ds, int port)
 		mt7530_rmw(priv, MT753X_MFC, MT7530_CPU_MASK, MT7530_CPU_EN |
 			   MT7530_CPU_PORT(port));
 
+	/* Add the CPU port to the CPU port bitmap for MT7531 and the switch on
+	 * the MT7988 SoC. Any frames set for trapping to CPU port will be
+	 * trapped to the CPU port the user port is affine to.
+	 */
+	if (priv->id == ID_MT7531 || priv->id == ID_MT7988)
+		mt7530_set(priv, MT7531_CFC, MT7531_CPU_PMAP(BIT(port)));
+
 	/* CPU port gets connected to all user ports of
 	 * the switch.
 	 */
@@ -2315,15 +2322,9 @@ static int
 mt7531_setup_common(struct dsa_switch *ds)
 {
 	struct mt7530_priv *priv = ds->priv;
-	struct dsa_port *cpu_dp;
 	int ret, i;
 
-	/* BPDU to CPU port */
-	dsa_switch_for_each_cpu_port(cpu_dp, ds) {
-		mt7530_rmw(priv, MT7531_CFC, MT7531_CPU_PMAP_MASK,
-			   BIT(cpu_dp->index));
-		break;
-	}
+	/* Trap BPDUs to the CPU port(s) */
 	mt7530_rmw(priv, MT753X_BPC, MT753X_BPDU_PORT_FW_MASK,
 		   MT753X_BPDU_CPU_ONLY);
 
diff --git a/drivers/net/dsa/mt7530.h b/drivers/net/dsa/mt7530.h
index 5ebb942b07ef..fd2a2f726b8a 100644
--- a/drivers/net/dsa/mt7530.h
+++ b/drivers/net/dsa/mt7530.h
@@ -53,7 +53,8 @@ enum mt753x_id {
 #define  MT7531_MIRROR_MASK		(0x7 << 16)
 #define  MT7531_MIRROR_PORT_GET(x)	(((x) >> 16) & 0x7)
 #define  MT7531_MIRROR_PORT_SET(x)	(((x) & 0x7) << 16)
-#define  MT7531_CPU_PMAP_MASK		GENMASK(7, 0)
+#define  MT7531_CPU_PMAP(x)		((x) & 0xff)
+#define  MT7531_CPU_PMAP_MASK		MT7531_CPU_PMAP(~0)
 
 #define MT753X_MIRROR_REG(id)		((((id) == ID_MT7531) || ((id) == ID_MT7988)) ?	\
 					 MT7531_CFC : MT753X_MFC)
-- 
2.39.2