[PATCH net-next v4 5/9] net: dsa: realtek: rtl8365mb: set and get vlan 4k for family D

[Mieczyslaw Nalewaj <namiltd@yahoo.com>]

The hardware structure of 4K VLAN table entries has changed between
silicon families. Family D's CVLAN entry is two 16-bit words rather
than three: there is no third word extending member/untag past bit 7,
and no priority/meter fields at all. The FID field is restricted to a
narrower 2-bit width. The chip itself supports both IVL and SVL, but
this driver always requests IVL for VLAN 4K entries
(rtl8365mb_vlan_4k_port_set() sets ivl_en = true on both families), so
both the IVL_EN (bit 3) and SVLAN_CHK_IVL_SVL (bit 2) controls are
forced to 1 here, as in the vendor RTL8367D code. Setting
SVLAN_CHK_IVL_SVL to 1 enforces strict lookup engine validation for
the selected IVL mode, preventing potential MAC learning leaks across
distinct VLAN boundaries during mixed frame processing. This matches
existing driver behavior and is not a hardware limitation.
vlan4k->ivl_en is still read back from IVL_EN.

Reusing the three-word family C layout unconditionally means the third
word is read from and written back to the register that holds it on
family C, but does not exist as a distinct table word on family D's
die; whatever data happens to be there gets folded into member/untag
bits [10:8] on read, and re-written on every read-modify-write cycle
in rtl8365mb_vlan_4k_port_set(). Give family D its own two-word
pack/unpack instead.

The two-word layout matches the vendor switch API for this chip
family, which writes only 0x0510/0x0511 for a CVLAN entry.

Signed-off-by: Mieczyslaw Nalewaj <namiltd@yahoo.com>
---
 drivers/net/dsa/realtek/rtl8365mb_vlan.c | 173 ++++++++++++++++-------
 1 file changed, 121 insertions(+), 52 deletions(-)

diff --git a/drivers/net/dsa/realtek/rtl8365mb_vlan.c b/drivers/net/dsa/realtek/rtl8365mb_vlan.c
index 8d49ffa..206a001 100644
--- a/drivers/net/dsa/realtek/rtl8365mb_vlan.c
+++ b/drivers/net/dsa/realtek/rtl8365mb_vlan.c
@@ -33,7 +33,9 @@
  * 1. VLAN4k entries can specify whether to use Independent or Shared VLAN
  *    Learning (IVL or SVL respectively). VLAN membership config entries
  *    cannot. This underscores the fact that VLAN membership configs are not
- *    involved in the learning process of the ASIC.
+ *    involved in the learning process of the ASIC. (The driver honors this
+ *    selection on family C only; on family D it always forces IVL, see
+ *    rtl8365mb_vlan_4k_write().)
  *
  * 2. VLAN membership config entries use an "enhanced VLAN ID" (efid), which has
  *    a range 0~8191 compared with the standard 0~4095 range of the VLAN4k
@@ -48,12 +50,16 @@
 
 #include "rtl8365mb_vlan.h"
 #include "rtl8365mb_table.h"
+#include "rtl8365mb.h"
 #include <linux/if_bridge.h>
 #include <linux/lockdep.h>
 #include <linux/regmap.h>
 
-/* CVLAN (i.e. VLAN4k) table entry layout, u16[3] */
+/* CVLAN (i.e. VLAN4k) table entry layout: u16[3] on family C, u16[2] on
+ * family D
+ */
 #define RTL8365MB_CVLAN_ENTRY_SIZE			3 /* 48-bits */
+#define RTL8365MB_D_CVLAN_ENTRY_SIZE			2 /* 32-bits */
 #define RTL8365MB_CVLAN_ENTRY_D0_MBR_MASK		GENMASK(7, 0)
 #define   RTL8365MB_CVLAN_MBR_LO_MASK			GENMASK(7, 0)
 #define RTL8365MB_CVLAN_ENTRY_D0_UNTAG_MASK		GENMASK(15, 8)
@@ -65,6 +71,11 @@
 #define RTL8365MB_CVLAN_ENTRY_D1_METERIDX_MASK		GENMASK(13, 9)
 #define   RTL8365MB_CVLAN_METERIDX_LO_MASK		GENMASK(4, 0)
 #define RTL8365MB_CVLAN_ENTRY_D1_IVL_SVL_MASK		GENMASK(14, 14)
+/* Family D CVLAN entry, word 1 (family D has no word 2) */
+#define RTL8365MB_D_CVLAN_ENTRY_D1_SVLAN_CHK_IVL_SVL_MASK \
+							GENMASK(2, 2)
+#define RTL8365MB_D_CVLAN_ENTRY_D1_IVL_EN_MASK		GENMASK(3, 3)
+#define RTL8365MB_D_CVLAN_ENTRY_D1_FID_MASK		GENMASK(1, 0)
 /* extends RTL8365MB_CVLAN_ENTRY_D0_MBR_MASK */
 #define RTL8365MB_CVLAN_ENTRY_D2_MBR_EXT_MASK		GENMASK(2, 0)
 #define   RTL8365MB_CVLAN_MBR_HI_MASK			GENMASK(10, 8)
@@ -132,7 +143,8 @@
  * @priority: priority classification (unused)
  * @priority_en: enable priority (unused)
  * @policing_en: enable policing (unused)
- * @ivl_en: enable IVL instead of default SVL
+ * @ivl_en: enable IVL instead of default SVL (family D always forces IVL
+ *          on write, see rtl8365mb_vlan_4k_write())
  * @meteridx: metering index (unused)
  *
  * This structure is used to get/set entries in the VLAN4k table. The
@@ -185,13 +197,16 @@ struct rtl8365mb_vlanmc {
 static int rtl8365mb_vlan_4k_read(struct realtek_priv *priv, u16 vid,
 				  struct rtl8365mb_vlan4k *vlan4k)
 {
+	bool is_d = rtl8365mb_get_family(priv) == RTL8365MB_FAMILY_D;
+	size_t entry_size = is_d ? RTL8365MB_D_CVLAN_ENTRY_SIZE :
+				   RTL8365MB_CVLAN_ENTRY_SIZE;
 	u16 data[RTL8365MB_CVLAN_ENTRY_SIZE];
 	int val;
 	int ret;
 
 	ret = rtl8365mb_table_query(priv, RTL8365MB_TABLE_CVLAN,
 				    RTL8365MB_TABLE_OP_READ, &vid, 0, 0,
-				    data, ARRAY_SIZE(data));
+				    data, entry_size);
 	if (ret)
 		return ret;
 
@@ -199,33 +214,61 @@ static int rtl8365mb_vlan_4k_read(struct realtek_priv *priv, u16 vid,
 	memset(vlan4k, 0, sizeof(*vlan4k));
 	vlan4k->vid = vid;
 
+	/* member/untag: d0[7:0]/d0[15:8] on both families. Family C
+	 * extends these into data[2] bits [2:0]/[5:3] for its 9th-11th
+	 * ports; family D's die has only 8 ports and no third table
+	 * word, so data[2] does not exist there and must not be read.
+	 */
 	val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D0_MBR_MASK, data[0]);
 	vlan4k->member = FIELD_PREP(RTL8365MB_CVLAN_MBR_LO_MASK, val);
-	val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D2_MBR_EXT_MASK, data[2]);
-	vlan4k->member |= FIELD_PREP(RTL8365MB_CVLAN_MBR_HI_MASK, val);
+	if (!is_d) {
+		val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D2_MBR_EXT_MASK, data[2]);
+		vlan4k->member |= FIELD_PREP(RTL8365MB_CVLAN_MBR_HI_MASK, val);
+	}
 
 	val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D0_UNTAG_MASK, data[0]);
 	vlan4k->untag = FIELD_PREP(RTL8365MB_CVLAN_UNTAG_LO_MASK, val);
-	val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D2_UNTAG_EXT_MASK, data[2]);
-	vlan4k->untag |= FIELD_PREP(RTL8365MB_CVLAN_UNTAG_HI_MASK, val);
-
-	vlan4k->fid = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_FID_MASK, data[1]);
-	vlan4k->priority_en =
-		FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_VBPEN_MASK, data[1]);
-	vlan4k->priority =
-		FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_VBPRI_MASK, data[1]);
-	vlan4k->policing_en =
-		FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_ENVLANPOL_MASK, data[1]);
-
-	val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_METERIDX_MASK, data[1]);
-	val = FIELD_PREP(RTL8365MB_CVLAN_METERIDX_LO_MASK, val);
-	vlan4k->meteridx = val;
-	val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D2_METERIDX_EXT_MASK, data[2]);
-	val = FIELD_PREP(RTL8365MB_CVLAN_METERIDX_HI_MASK, val);
-	vlan4k->meteridx |= val;
-
-	vlan4k->ivl_en =
-		FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_IVL_SVL_MASK, data[1]);
+	if (!is_d) {
+		val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D2_UNTAG_EXT_MASK,
+				data[2]);
+		vlan4k->untag |= FIELD_PREP(RTL8365MB_CVLAN_UNTAG_HI_MASK, val);
+	}
+
+	if (is_d) {
+		vlan4k->fid = FIELD_GET(RTL8365MB_D_CVLAN_ENTRY_D1_FID_MASK,
+					data[1]);
+		/* Family D has no priority/meter fields in this entry -
+		 * left zeroed by the memset() above.
+		 */
+		vlan4k->ivl_en =
+			FIELD_GET(RTL8365MB_D_CVLAN_ENTRY_D1_IVL_EN_MASK,
+				  data[1]);
+	} else {
+		vlan4k->fid = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_FID_MASK,
+					data[1]);
+		vlan4k->priority_en =
+			FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_VBPEN_MASK,
+				  data[1]);
+		vlan4k->priority =
+			FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_VBPRI_MASK,
+				  data[1]);
+		vlan4k->policing_en =
+			FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_ENVLANPOL_MASK,
+				  data[1]);
+
+		val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_METERIDX_MASK,
+				data[1]);
+		val = FIELD_PREP(RTL8365MB_CVLAN_METERIDX_LO_MASK, val);
+		vlan4k->meteridx = val;
+		val = FIELD_GET(RTL8365MB_CVLAN_ENTRY_D2_METERIDX_EXT_MASK,
+				data[2]);
+		val = FIELD_PREP(RTL8365MB_CVLAN_METERIDX_HI_MASK, val);
+		vlan4k->meteridx |= val;
+
+		vlan4k->ivl_en =
+			FIELD_GET(RTL8365MB_CVLAN_ENTRY_D1_IVL_SVL_MASK,
+				  data[1]);
+	}
 
 	return 0;
 }
@@ -233,6 +276,9 @@ static int rtl8365mb_vlan_4k_read(struct realtek_priv *priv, u16 vid,
 static int rtl8365mb_vlan_4k_write(struct realtek_priv *priv,
 				   const struct rtl8365mb_vlan4k *vlan4k)
 {
+	bool is_d = rtl8365mb_get_family(priv) == RTL8365MB_FAMILY_D;
+	size_t entry_size = is_d ? RTL8365MB_D_CVLAN_ENTRY_SIZE :
+				   RTL8365MB_CVLAN_ENTRY_SIZE;
 	u16 data[RTL8365MB_CVLAN_ENTRY_SIZE] = { 0 };
 	u16 vid;
 	int val;
@@ -244,36 +290,59 @@ static int rtl8365mb_vlan_4k_write(struct realtek_priv *priv,
 	val = FIELD_GET(RTL8365MB_CVLAN_UNTAG_LO_MASK, vlan4k->untag);
 	data[0] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D0_UNTAG_MASK, val);
 
-	data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_FID_MASK, vlan4k->fid);
-	data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_VBPEN_MASK,
-			      vlan4k->priority_en);
-	data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_VBPRI_MASK,
-			      vlan4k->priority);
-	data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_ENVLANPOL_MASK,
-			      vlan4k->policing_en);
-
-	/* FIELD_* does not play nice with struct bitfield. */
-	val = vlan4k->meteridx;
-	val = FIELD_GET(RTL8365MB_CVLAN_METERIDX_LO_MASK, val);
-	data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_METERIDX_MASK, val);
-
-	data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_IVL_SVL_MASK,
-			      vlan4k->ivl_en);
-
-	val = FIELD_GET(RTL8365MB_CVLAN_MBR_HI_MASK, vlan4k->member);
-	data[2] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D2_MBR_EXT_MASK, val);
-
-	val = FIELD_GET(RTL8365MB_CVLAN_UNTAG_HI_MASK, vlan4k->untag);
-	data[2] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D2_UNTAG_EXT_MASK, val);
-
-	val = vlan4k->meteridx;
-	val = FIELD_GET(RTL8365MB_CVLAN_METERIDX_HI_MASK, val);
-	data[2] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D2_METERIDX_EXT_MASK, val);
+	if (is_d) {
+		/* The chip supports both IVL and SVL, but the caller (see
+		 * rtl8365mb_vlan_4k_port_set()) never requests SVL, so both
+		 * IVL/SVL selector bits are forced here rather than threaded
+		 * through from vlan4k->ivl_en, which family C does honor.
+		 */
+		data[1] |= FIELD_PREP(RTL8365MB_D_CVLAN_ENTRY_D1_IVL_EN_MASK,
+				      1) |
+			   FIELD_PREP(RTL8365MB_D_CVLAN_ENTRY_D1_SVLAN_CHK_IVL_SVL_MASK,
+				      1);
+		data[1] |= FIELD_PREP(RTL8365MB_D_CVLAN_ENTRY_D1_FID_MASK,
+				      vlan4k->fid);
+		/* No priority/meter/member-untag-extension fields exist in
+		 * family D's 2-word entry - data[1] and data[0] above are
+		 * the whole entry, and data[2] is not part of it at all.
+		 */
+	} else {
+		val = vlan4k->fid;
+		data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_FID_MASK, val);
+		data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_VBPEN_MASK,
+				      vlan4k->priority_en);
+		data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_VBPRI_MASK,
+				      vlan4k->priority);
+		data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_ENVLANPOL_MASK,
+				      vlan4k->policing_en);
+
+		/* FIELD_* does not play nice with struct bitfield. */
+		val = vlan4k->meteridx;
+		val = FIELD_GET(RTL8365MB_CVLAN_METERIDX_LO_MASK, val);
+		data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_METERIDX_MASK,
+				      val);
+
+		data[1] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D1_IVL_SVL_MASK,
+				      vlan4k->ivl_en);
+
+		val = FIELD_GET(RTL8365MB_CVLAN_MBR_HI_MASK, vlan4k->member);
+		data[2] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D2_MBR_EXT_MASK,
+				      val);
+
+		val = FIELD_GET(RTL8365MB_CVLAN_UNTAG_HI_MASK, vlan4k->untag);
+		data[2] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D2_UNTAG_EXT_MASK,
+				      val);
+
+		val = vlan4k->meteridx;
+		val = FIELD_GET(RTL8365MB_CVLAN_METERIDX_HI_MASK, val);
+		data[2] |= FIELD_PREP(RTL8365MB_CVLAN_ENTRY_D2_METERIDX_EXT_MASK,
+				      val);
+	}
 
 	vid = vlan4k->vid;
 	return rtl8365mb_table_query(priv, RTL8365MB_TABLE_CVLAN,
 				     RTL8365MB_TABLE_OP_WRITE, &vid, 0, 0,
-				     data, ARRAY_SIZE(data));
+				     data, entry_size);
 }
 
 static int
-- 
2.53.0