diff mbox series

[v5,net-next,14/15] net: dsa: mv88e6xxx: Export STU as devlink region

Message ID 20220316150857.2442916-15-tobias@waldekranz.com (mailing list archive)
State Accepted
Commit 7dc96039b9676b9360b49d4fd117fa042f7d456f
Delegated to: Netdev Maintainers
Headers show
Series net: bridge: Multiple Spanning Trees | expand

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netdev/tree_selection success Clearly marked for net-next
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netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 125 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Tobias Waldekranz March 16, 2022, 3:08 p.m. UTC
Export the raw STU data in a devlink region so that it can be
inspected from userspace and compared to the current bridge
configuration.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
---
 drivers/net/dsa/mv88e6xxx/chip.h    |  1 +
 drivers/net/dsa/mv88e6xxx/devlink.c | 94 +++++++++++++++++++++++++++++
 2 files changed, 95 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/dsa/mv88e6xxx/chip.h b/drivers/net/dsa/mv88e6xxx/chip.h
index be654be69982..6d4daa24d3e5 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.h
+++ b/drivers/net/dsa/mv88e6xxx/chip.h
@@ -287,6 +287,7 @@  enum mv88e6xxx_region_id {
 	MV88E6XXX_REGION_GLOBAL2,
 	MV88E6XXX_REGION_ATU,
 	MV88E6XXX_REGION_VTU,
+	MV88E6XXX_REGION_STU,
 	MV88E6XXX_REGION_PVT,
 
 	_MV88E6XXX_REGION_MAX,
diff --git a/drivers/net/dsa/mv88e6xxx/devlink.c b/drivers/net/dsa/mv88e6xxx/devlink.c
index 381068395c63..1266eabee086 100644
--- a/drivers/net/dsa/mv88e6xxx/devlink.c
+++ b/drivers/net/dsa/mv88e6xxx/devlink.c
@@ -503,6 +503,85 @@  static int mv88e6xxx_region_vtu_snapshot(struct devlink *dl,
 	return 0;
 }
 
+/**
+ * struct mv88e6xxx_devlink_stu_entry - Devlink STU entry
+ * @sid:   Global1/3:   SID, unknown filters and learning.
+ * @vid:   Global1/6:   Valid bit.
+ * @data:  Global1/7-9: Membership data and priority override.
+ * @resvd: Reserved. In case we forgot something.
+ *
+ * The STU entry format varies between chipset generations. Peridot
+ * and Amethyst packs the STU data into Global1/7-8. Older silicon
+ * spreads the information across all three VTU data registers -
+ * inheriting the layout of even older hardware that had no STU at
+ * all. Since this is a low-level debug interface, copy all data
+ * verbatim and defer parsing to the consumer.
+ */
+struct mv88e6xxx_devlink_stu_entry {
+	u16 sid;
+	u16 vid;
+	u16 data[3];
+	u16 resvd;
+};
+
+static int mv88e6xxx_region_stu_snapshot(struct devlink *dl,
+					 const struct devlink_region_ops *ops,
+					 struct netlink_ext_ack *extack,
+					 u8 **data)
+{
+	struct mv88e6xxx_devlink_stu_entry *table, *entry;
+	struct dsa_switch *ds = dsa_devlink_to_ds(dl);
+	struct mv88e6xxx_chip *chip = ds->priv;
+	struct mv88e6xxx_stu_entry stu;
+	int err;
+
+	table = kcalloc(mv88e6xxx_max_sid(chip) + 1,
+			sizeof(struct mv88e6xxx_devlink_stu_entry),
+			GFP_KERNEL);
+	if (!table)
+		return -ENOMEM;
+
+	entry = table;
+	stu.sid = mv88e6xxx_max_sid(chip);
+	stu.valid = false;
+
+	mv88e6xxx_reg_lock(chip);
+
+	do {
+		err = mv88e6xxx_g1_stu_getnext(chip, &stu);
+		if (err)
+			break;
+
+		if (!stu.valid)
+			break;
+
+		err = err ? : mv88e6xxx_g1_read(chip, MV88E6352_G1_VTU_SID,
+						&entry->sid);
+		err = err ? : mv88e6xxx_g1_read(chip, MV88E6XXX_G1_VTU_VID,
+						&entry->vid);
+		err = err ? : mv88e6xxx_g1_read(chip, MV88E6XXX_G1_VTU_DATA1,
+						&entry->data[0]);
+		err = err ? : mv88e6xxx_g1_read(chip, MV88E6XXX_G1_VTU_DATA2,
+						&entry->data[1]);
+		err = err ? : mv88e6xxx_g1_read(chip, MV88E6XXX_G1_VTU_DATA3,
+						&entry->data[2]);
+		if (err)
+			break;
+
+		entry++;
+	} while (stu.sid < mv88e6xxx_max_sid(chip));
+
+	mv88e6xxx_reg_unlock(chip);
+
+	if (err) {
+		kfree(table);
+		return err;
+	}
+
+	*data = (u8 *)table;
+	return 0;
+}
+
 static int mv88e6xxx_region_pvt_snapshot(struct devlink *dl,
 					 const struct devlink_region_ops *ops,
 					 struct netlink_ext_ack *extack,
@@ -605,6 +684,12 @@  static struct devlink_region_ops mv88e6xxx_region_vtu_ops = {
 	.destructor = kfree,
 };
 
+static struct devlink_region_ops mv88e6xxx_region_stu_ops = {
+	.name = "stu",
+	.snapshot = mv88e6xxx_region_stu_snapshot,
+	.destructor = kfree,
+};
+
 static struct devlink_region_ops mv88e6xxx_region_pvt_ops = {
 	.name = "pvt",
 	.snapshot = mv88e6xxx_region_pvt_snapshot,
@@ -640,6 +725,11 @@  static struct mv88e6xxx_region mv88e6xxx_regions[] = {
 		.ops = &mv88e6xxx_region_vtu_ops
 	  /* calculated at runtime */
 	},
+	[MV88E6XXX_REGION_STU] = {
+		.ops = &mv88e6xxx_region_stu_ops,
+		.cond = mv88e6xxx_has_stu,
+	  /* calculated at runtime */
+	},
 	[MV88E6XXX_REGION_PVT] = {
 		.ops = &mv88e6xxx_region_pvt_ops,
 		.size = MV88E6XXX_MAX_PVT_ENTRIES * sizeof(u16),
@@ -706,6 +796,10 @@  int mv88e6xxx_setup_devlink_regions_global(struct dsa_switch *ds)
 			size = (mv88e6xxx_max_vid(chip) + 1) *
 				sizeof(struct mv88e6xxx_devlink_vtu_entry);
 			break;
+		case MV88E6XXX_REGION_STU:
+			size = (mv88e6xxx_max_sid(chip) + 1) *
+				sizeof(struct mv88e6xxx_devlink_stu_entry);
+			break;
 		}
 
 		region = dsa_devlink_region_create(ds, ops, 1, size);