net: microchip: sparx5: Adding initial tc flower support for VCAP API

This adds initial TC flower filter support to Sparx5 for the IS2 VCAP.

The support consists of the source and destination MAC addresses,
and the trap and pass actions.

This is how you can create a rule that test the functionality:

tc qdisc add dev eth0 clsact
tc filter add dev eth0 ingress chain 8000000 prio 10 handle 10 \
      protocol all flower skip_sw \
      dst_mac 0a:0b:0c:0d:0e:0f \
      src_mac 2:0:0:0:0:1 \
      action trap

The IS2 chains in Sparx5 are assigned like this:

- chain 8000000: IS2 Lookup 0
- chain 8100000: IS2 Lookup 1
- chain 8200000: IS2 Lookup 2
- chain 8300000: IS2 Lookup 3

Signed-off-by: Steen Hegelund <steen.hegelund@microchip.com>
Tested-by: Casper Andersson <casper.casan@gmail.com>
Reviewed-by: Casper Andersson <casper.casan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 371 insertions, 0 deletions

diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api.c b/drivers/net/ethernet/microchip/vcap/vcap_api.c
new file mode 100644
index 000000000000..3eb8aa237c8e
--- /dev/null
+++ b/drivers/net/ethernet/microchip/vcap/vcap_api.c
@@ -0,0 +1,371 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Microchip VCAP API
+ *
+ * Copyright (c) 2022 Microchip Technology Inc. and its subsidiaries.
+ */
+
+#include <linux/types.h>
+
+#include "vcap_api.h"
+#include "vcap_api_client.h"
+
+#define to_intrule(rule) container_of((rule), struct vcap_rule_internal, data)
+
+/* Private VCAP API rule data */
+struct vcap_rule_internal {
+	struct vcap_rule data; /* provided by the client */
+	struct list_head list; /* for insertion in the vcap admin list of rules */
+	struct vcap_admin *admin; /* vcap hw instance */
+	struct net_device *ndev;  /* the interface that the rule applies to */
+	struct vcap_control *vctrl; /* the client control */
+	u32 addr; /* address in the VCAP at insertion */
+};
+
+/* Update the keyset for the rule */
+int vcap_set_rule_set_keyset(struct vcap_rule *rule,
+			     enum vcap_keyfield_set keyset)
+{
+	/* This will be expanded with more information later */
+	rule->keyset = keyset;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vcap_set_rule_set_keyset);
+
+/* Update the actionset for the rule */
+int vcap_set_rule_set_actionset(struct vcap_rule *rule,
+				enum vcap_actionfield_set actionset)
+{
+	/* This will be expanded with more information later */
+	rule->actionset = actionset;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vcap_set_rule_set_actionset);
+
+/* Find a rule with a provided rule id */
+static struct vcap_rule_internal *vcap_lookup_rule(struct vcap_control *vctrl,
+						   u32 id)
+{
+	struct vcap_rule_internal *ri;
+	struct vcap_admin *admin;
+
+	/* Look for the rule id in all vcaps */
+	list_for_each_entry(admin, &vctrl->list, list)
+		list_for_each_entry(ri, &admin->rules, list)
+			if (ri->data.id == id)
+				return ri;
+	return NULL;
+}
+
+/* Find a rule id with a provided cookie */
+int vcap_lookup_rule_by_cookie(struct vcap_control *vctrl, u64 cookie)
+{
+	struct vcap_rule_internal *ri;
+	struct vcap_admin *admin;
+
+	/* Look for the rule id in all vcaps */
+	list_for_each_entry(admin, &vctrl->list, list)
+		list_for_each_entry(ri, &admin->rules, list)
+			if (ri->data.cookie == cookie)
+				return ri->data.id;
+	return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(vcap_lookup_rule_by_cookie);
+
+/* Lookup a vcap instance using chain id */
+struct vcap_admin *vcap_find_admin(struct vcap_control *vctrl, int cid)
+{
+	struct vcap_admin *admin;
+
+	list_for_each_entry(admin, &vctrl->list, list) {
+		if (cid >= admin->first_cid && cid <= admin->last_cid)
+			return admin;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(vcap_find_admin);
+
+/* Validate a rule with respect to available port keys */
+int vcap_val_rule(struct vcap_rule *rule, u16 l3_proto)
+{
+	struct vcap_rule_internal *ri = to_intrule(rule);
+
+	/* This validation will be much expanded later */
+	if (!ri->admin) {
+		ri->data.exterr = VCAP_ERR_NO_ADMIN;
+		return -EINVAL;
+	}
+	if (!ri->ndev) {
+		ri->data.exterr = VCAP_ERR_NO_NETDEV;
+		return -EINVAL;
+	}
+	if (ri->data.keyset == VCAP_KFS_NO_VALUE) {
+		ri->data.exterr = VCAP_ERR_NO_KEYSET_MATCH;
+		return -EINVAL;
+	}
+	if (ri->data.actionset == VCAP_AFS_NO_VALUE) {
+		ri->data.exterr = VCAP_ERR_NO_ACTIONSET_MATCH;
+		return -EINVAL;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vcap_val_rule);
+
+/* Assign a unique rule id and autogenerate one if id == 0 */
+static u32 vcap_set_rule_id(struct vcap_rule_internal *ri)
+{
+	u32 next_id;
+
+	if (ri->data.id != 0)
+		return ri->data.id;
+
+	next_id = ri->vctrl->rule_id + 1;
+
+	for (next_id = ri->vctrl->rule_id + 1; next_id < ~0; ++next_id) {
+		if (!vcap_lookup_rule(ri->vctrl, next_id)) {
+			ri->data.id = next_id;
+			ri->vctrl->rule_id = next_id;
+			break;
+		}
+	}
+	return ri->data.id;
+}
+
+/* Encode and write a validated rule to the VCAP */
+int vcap_add_rule(struct vcap_rule *rule)
+{
+	/* This will later handling the encode and writing of the rule */
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vcap_add_rule);
+
+/* Allocate a new rule with the provided arguments */
+struct vcap_rule *vcap_alloc_rule(struct vcap_control *vctrl,
+				  struct net_device *ndev, int vcap_chain_id,
+				  enum vcap_user user, u16 priority,
+				  u32 id)
+{
+	struct vcap_rule_internal *ri;
+	struct vcap_admin *admin;
+
+	if (!ndev)
+		return ERR_PTR(-ENODEV);
+	/* Get the VCAP instance */
+	admin = vcap_find_admin(vctrl, vcap_chain_id);
+	if (!admin)
+		return ERR_PTR(-ENOENT);
+	/* Create a container for the rule and return it */
+	ri = kzalloc(sizeof(*ri), GFP_KERNEL);
+	if (!ri)
+		return ERR_PTR(-ENOMEM);
+	ri->data.vcap_chain_id = vcap_chain_id;
+	ri->data.user = user;
+	ri->data.priority = priority;
+	ri->data.id = id;
+	ri->data.keyset = VCAP_KFS_NO_VALUE;
+	ri->data.actionset = VCAP_AFS_NO_VALUE;
+	INIT_LIST_HEAD(&ri->list);
+	INIT_LIST_HEAD(&ri->data.keyfields);
+	INIT_LIST_HEAD(&ri->data.actionfields);
+	ri->ndev = ndev;
+	ri->admin = admin; /* refer to the vcap instance */
+	ri->vctrl = vctrl; /* refer to the client */
+	if (vcap_set_rule_id(ri) == 0)
+		goto out_free;
+	return (struct vcap_rule *)ri;
+
+out_free:
+	kfree(ri);
+	return ERR_PTR(-EINVAL);
+}
+EXPORT_SYMBOL_GPL(vcap_alloc_rule);
+
+/* Free mem of a rule owned by client after the rule as been added to the VCAP */
+void vcap_free_rule(struct vcap_rule *rule)
+{
+	struct vcap_rule_internal *ri = to_intrule(rule);
+	struct vcap_client_actionfield *caf, *next_caf;
+	struct vcap_client_keyfield *ckf, *next_ckf;
+
+	/* Deallocate the list of keys and actions */
+	list_for_each_entry_safe(ckf, next_ckf, &ri->data.keyfields, ctrl.list) {
+		list_del(&ckf->ctrl.list);
+		kfree(ckf);
+	}
+	list_for_each_entry_safe(caf, next_caf, &ri->data.actionfields, ctrl.list) {
+		list_del(&caf->ctrl.list);
+		kfree(caf);
+	}
+	/* Deallocate the rule */
+	kfree(rule);
+}
+EXPORT_SYMBOL_GPL(vcap_free_rule);
+
+/* Delete rule in a VCAP instance */
+int vcap_del_rule(struct vcap_control *vctrl, struct net_device *ndev, u32 id)
+{
+	struct vcap_rule_internal *ri, *elem;
+	struct vcap_admin *admin;
+
+	/* This will later also handle rule moving */
+	if (!ndev)
+		return -ENODEV;
+	/* Look for the rule id in all vcaps */
+	ri = vcap_lookup_rule(vctrl, id);
+	if (!ri)
+		return -EINVAL;
+	admin = ri->admin;
+	list_del(&ri->list);
+	if (list_empty(&admin->rules)) {
+		admin->last_used_addr = admin->last_valid_addr;
+	} else {
+		/* update the address range end marker from the last rule in the list */
+		elem = list_last_entry(&admin->rules, struct vcap_rule_internal, list);
+		admin->last_used_addr = elem->addr;
+	}
+	kfree(ri);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vcap_del_rule);
+
+static void vcap_copy_from_client_keyfield(struct vcap_rule *rule,
+					   struct vcap_client_keyfield *field,
+					   struct vcap_client_keyfield_data *data)
+{
+	/* This will be expanded later to handle different vcap memory layouts */
+	memcpy(&field->data, data, sizeof(field->data));
+}
+
+static int vcap_rule_add_key(struct vcap_rule *rule,
+			     enum vcap_key_field key,
+			     enum vcap_field_type ftype,
+			     struct vcap_client_keyfield_data *data)
+{
+	struct vcap_client_keyfield *field;
+
+	/* More validation will be added here later */
+	field = kzalloc(sizeof(*field), GFP_KERNEL);
+	if (!field)
+		return -ENOMEM;
+	field->ctrl.key = key;
+	field->ctrl.type = ftype;
+	vcap_copy_from_client_keyfield(rule, field, data);
+	list_add_tail(&field->ctrl.list, &rule->keyfields);
+	return 0;
+}
+
+/* Add a 48 bit key with value and mask to the rule */
+int vcap_rule_add_key_u48(struct vcap_rule *rule, enum vcap_key_field key,
+			  struct vcap_u48_key *fieldval)
+{
+	struct vcap_client_keyfield_data data;
+
+	memcpy(&data.u48, fieldval, sizeof(data.u48));
+	return vcap_rule_add_key(rule, key, VCAP_FIELD_U48, &data);
+}
+EXPORT_SYMBOL_GPL(vcap_rule_add_key_u48);
+
+static void vcap_copy_from_client_actionfield(struct vcap_rule *rule,
+					      struct vcap_client_actionfield *field,
+					      struct vcap_client_actionfield_data *data)
+{
+	/* This will be expanded later to handle different vcap memory layouts */
+	memcpy(&field->data, data, sizeof(field->data));
+}
+
+static int vcap_rule_add_action(struct vcap_rule *rule,
+				enum vcap_action_field action,
+				enum vcap_field_type ftype,
+				struct vcap_client_actionfield_data *data)
+{
+	struct vcap_client_actionfield *field;
+
+	/* More validation will be added here later */
+	field = kzalloc(sizeof(*field), GFP_KERNEL);
+	if (!field)
+		return -ENOMEM;
+	field->ctrl.action = action;
+	field->ctrl.type = ftype;
+	vcap_copy_from_client_actionfield(rule, field, data);
+	list_add_tail(&field->ctrl.list, &rule->actionfields);
+	return 0;
+}
+
+static void vcap_rule_set_action_bitsize(struct vcap_u1_action *u1,
+					 enum vcap_bit val)
+{
+	switch (val) {
+	case VCAP_BIT_0:
+		u1->value = 0;
+		break;
+	case VCAP_BIT_1:
+		u1->value = 1;
+		break;
+	case VCAP_BIT_ANY:
+		u1->value = 0;
+		break;
+	}
+}
+
+/* Add a bit action with value to the rule */
+int vcap_rule_add_action_bit(struct vcap_rule *rule,
+			     enum vcap_action_field action,
+			     enum vcap_bit val)
+{
+	struct vcap_client_actionfield_data data;
+
+	vcap_rule_set_action_bitsize(&data.u1, val);
+	return vcap_rule_add_action(rule, action, VCAP_FIELD_BIT, &data);
+}
+EXPORT_SYMBOL_GPL(vcap_rule_add_action_bit);
+
+/* Add a 32 bit action field with value to the rule */
+int vcap_rule_add_action_u32(struct vcap_rule *rule,
+			     enum vcap_action_field action,
+			     u32 value)
+{
+	struct vcap_client_actionfield_data data;
+
+	data.u32.value = value;
+	return vcap_rule_add_action(rule, action, VCAP_FIELD_U32, &data);
+}
+EXPORT_SYMBOL_GPL(vcap_rule_add_action_u32);
+
+/* Copy to host byte order */
+void vcap_netbytes_copy(u8 *dst, u8 *src, int count)
+{
+	int idx;
+
+	for (idx = 0; idx < count; ++idx, ++dst)
+		*dst = src[count - idx - 1];
+}
+EXPORT_SYMBOL_GPL(vcap_netbytes_copy);
+
+/* Convert validation error code into tc extact error message */
+void vcap_set_tc_exterr(struct flow_cls_offload *fco, struct vcap_rule *vrule)
+{
+	switch (vrule->exterr) {
+	case VCAP_ERR_NONE:
+		break;
+	case VCAP_ERR_NO_ADMIN:
+		NL_SET_ERR_MSG_MOD(fco->common.extack,
+				   "Missing VCAP instance");
+		break;
+	case VCAP_ERR_NO_NETDEV:
+		NL_SET_ERR_MSG_MOD(fco->common.extack,
+				   "Missing network interface");
+		break;
+	case VCAP_ERR_NO_KEYSET_MATCH:
+		NL_SET_ERR_MSG_MOD(fco->common.extack,
+				   "No keyset matched the filter keys");
+		break;
+	case VCAP_ERR_NO_ACTIONSET_MATCH:
+		NL_SET_ERR_MSG_MOD(fco->common.extack,
+				   "No actionset matched the filter actions");
+		break;
+	case VCAP_ERR_NO_PORT_KEYSET_MATCH:
+		NL_SET_ERR_MSG_MOD(fco->common.extack,
+				   "No port keyset matched the filter keys");
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(vcap_set_tc_exterr);