net/mlx5: Introduce vhca state event notifier

vhca state events indicates change in the state of the vhca that may
occur due to a SF allocation, deallocation or enabling/disabling the
SF HCA.

Introduce vhca state event handler which will be used by SF devlink
port manager and SF hardware id allocator in subsequent patches
to act on the event.

This enables single entity to subscribe, query and rearm the event
for a function.

Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Vu Pham <vuhuong@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

1 files changed, 189 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/vhca_event.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/vhca_event.c
new file mode 100644
index 000000000000..af2f2dd9db25
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/vhca_event.c
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2020 Mellanox Technologies Ltd */
+
+#include <linux/mlx5/driver.h>
+#include "mlx5_ifc_vhca_event.h"
+#include "mlx5_core.h"
+#include "vhca_event.h"
+#include "ecpf.h"
+
+struct mlx5_vhca_state_notifier {
+	struct mlx5_core_dev *dev;
+	struct mlx5_nb nb;
+	struct blocking_notifier_head n_head;
+};
+
+struct mlx5_vhca_event_work {
+	struct work_struct work;
+	struct mlx5_vhca_state_notifier *notifier;
+	struct mlx5_vhca_state_event event;
+};
+
+int mlx5_cmd_query_vhca_state(struct mlx5_core_dev *dev, u16 function_id,
+			      bool ecpu, u32 *out, u32 outlen)
+{
+	u32 in[MLX5_ST_SZ_DW(query_vhca_state_in)] = {};
+
+	MLX5_SET(query_vhca_state_in, in, opcode, MLX5_CMD_OP_QUERY_VHCA_STATE);
+	MLX5_SET(query_vhca_state_in, in, function_id, function_id);
+	MLX5_SET(query_vhca_state_in, in, embedded_cpu_function, ecpu);
+
+	return mlx5_cmd_exec(dev, in, sizeof(in), out, outlen);
+}
+
+static int mlx5_cmd_modify_vhca_state(struct mlx5_core_dev *dev, u16 function_id,
+				      bool ecpu, u32 *in, u32 inlen)
+{
+	u32 out[MLX5_ST_SZ_DW(modify_vhca_state_out)] = {};
+
+	MLX5_SET(modify_vhca_state_in, in, opcode, MLX5_CMD_OP_MODIFY_VHCA_STATE);
+	MLX5_SET(modify_vhca_state_in, in, function_id, function_id);
+	MLX5_SET(modify_vhca_state_in, in, embedded_cpu_function, ecpu);
+
+	return mlx5_cmd_exec(dev, in, inlen, out, sizeof(out));
+}
+
+int mlx5_modify_vhca_sw_id(struct mlx5_core_dev *dev, u16 function_id, bool ecpu, u32 sw_fn_id)
+{
+	u32 out[MLX5_ST_SZ_DW(modify_vhca_state_out)] = {};
+	u32 in[MLX5_ST_SZ_DW(modify_vhca_state_in)] = {};
+
+	MLX5_SET(modify_vhca_state_in, in, opcode, MLX5_CMD_OP_MODIFY_VHCA_STATE);
+	MLX5_SET(modify_vhca_state_in, in, function_id, function_id);
+	MLX5_SET(modify_vhca_state_in, in, embedded_cpu_function, ecpu);
+	MLX5_SET(modify_vhca_state_in, in, vhca_state_field_select.sw_function_id, 1);
+	MLX5_SET(modify_vhca_state_in, in, vhca_state_context.sw_function_id, sw_fn_id);
+
+	return mlx5_cmd_exec_inout(dev, modify_vhca_state, in, out);
+}
+
+int mlx5_vhca_event_arm(struct mlx5_core_dev *dev, u16 function_id, bool ecpu)
+{
+	u32 in[MLX5_ST_SZ_DW(modify_vhca_state_in)] = {};
+
+	MLX5_SET(modify_vhca_state_in, in, vhca_state_context.arm_change_event, 1);
+	MLX5_SET(modify_vhca_state_in, in, vhca_state_field_select.arm_change_event, 1);
+
+	return mlx5_cmd_modify_vhca_state(dev, function_id, ecpu, in, sizeof(in));
+}
+
+static void
+mlx5_vhca_event_notify(struct mlx5_core_dev *dev, struct mlx5_vhca_state_event *event)
+{
+	u32 out[MLX5_ST_SZ_DW(query_vhca_state_out)] = {};
+	int err;
+
+	err = mlx5_cmd_query_vhca_state(dev, event->function_id, event->ecpu, out, sizeof(out));
+	if (err)
+		return;
+
+	event->sw_function_id = MLX5_GET(query_vhca_state_out, out,
+					 vhca_state_context.sw_function_id);
+	event->new_vhca_state = MLX5_GET(query_vhca_state_out, out,
+					 vhca_state_context.vhca_state);
+
+	mlx5_vhca_event_arm(dev, event->function_id, event->ecpu);
+
+	blocking_notifier_call_chain(&dev->priv.vhca_state_notifier->n_head, 0, event);
+}
+
+static void mlx5_vhca_state_work_handler(struct work_struct *_work)
+{
+	struct mlx5_vhca_event_work *work = container_of(_work, struct mlx5_vhca_event_work, work);
+	struct mlx5_vhca_state_notifier *notifier = work->notifier;
+	struct mlx5_core_dev *dev = notifier->dev;
+
+	mlx5_vhca_event_notify(dev, &work->event);
+}
+
+static int
+mlx5_vhca_state_change_notifier(struct notifier_block *nb, unsigned long type, void *data)
+{
+	struct mlx5_vhca_state_notifier *notifier =
+				mlx5_nb_cof(nb, struct mlx5_vhca_state_notifier, nb);
+	struct mlx5_vhca_event_work *work;
+	struct mlx5_eqe *eqe = data;
+
+	work = kzalloc(sizeof(*work), GFP_ATOMIC);
+	if (!work)
+		return NOTIFY_DONE;
+	INIT_WORK(&work->work, &mlx5_vhca_state_work_handler);
+	work->notifier = notifier;
+	work->event.function_id = be16_to_cpu(eqe->data.vhca_state.function_id);
+	work->event.ecpu = be16_to_cpu(eqe->data.vhca_state.ec_function);
+	mlx5_events_work_enqueue(notifier->dev, &work->work);
+	return NOTIFY_OK;
+}
+
+void mlx5_vhca_state_cap_handle(struct mlx5_core_dev *dev, void *set_hca_cap)
+{
+	if (!mlx5_vhca_event_supported(dev))
+		return;
+
+	MLX5_SET(cmd_hca_cap, set_hca_cap, vhca_state, 1);
+	MLX5_SET(cmd_hca_cap, set_hca_cap, event_on_vhca_state_allocated, 1);
+	MLX5_SET(cmd_hca_cap, set_hca_cap, event_on_vhca_state_active, 1);
+	MLX5_SET(cmd_hca_cap, set_hca_cap, event_on_vhca_state_in_use, 1);
+	MLX5_SET(cmd_hca_cap, set_hca_cap, event_on_vhca_state_teardown_request, 1);
+}
+
+int mlx5_vhca_event_init(struct mlx5_core_dev *dev)
+{
+	struct mlx5_vhca_state_notifier *notifier;
+
+	if (!mlx5_vhca_event_supported(dev))
+		return 0;
+
+	notifier = kzalloc(sizeof(*notifier), GFP_KERNEL);
+	if (!notifier)
+		return -ENOMEM;
+
+	dev->priv.vhca_state_notifier = notifier;
+	notifier->dev = dev;
+	BLOCKING_INIT_NOTIFIER_HEAD(&notifier->n_head);
+	MLX5_NB_INIT(&notifier->nb, mlx5_vhca_state_change_notifier, VHCA_STATE_CHANGE);
+	return 0;
+}
+
+void mlx5_vhca_event_cleanup(struct mlx5_core_dev *dev)
+{
+	if (!mlx5_vhca_event_supported(dev))
+		return;
+
+	kfree(dev->priv.vhca_state_notifier);
+	dev->priv.vhca_state_notifier = NULL;
+}
+
+void mlx5_vhca_event_start(struct mlx5_core_dev *dev)
+{
+	struct mlx5_vhca_state_notifier *notifier;
+
+	if (!dev->priv.vhca_state_notifier)
+		return;
+
+	notifier = dev->priv.vhca_state_notifier;
+	mlx5_eq_notifier_register(dev, &notifier->nb);
+}
+
+void mlx5_vhca_event_stop(struct mlx5_core_dev *dev)
+{
+	struct mlx5_vhca_state_notifier *notifier;
+
+	if (!dev->priv.vhca_state_notifier)
+		return;
+
+	notifier = dev->priv.vhca_state_notifier;
+	mlx5_eq_notifier_unregister(dev, &notifier->nb);
+}
+
+int mlx5_vhca_event_notifier_register(struct mlx5_core_dev *dev, struct notifier_block *nb)
+{
+	if (!dev->priv.vhca_state_notifier)
+		return -EOPNOTSUPP;
+	return blocking_notifier_chain_register(&dev->priv.vhca_state_notifier->n_head, nb);
+}
+
+void mlx5_vhca_event_notifier_unregister(struct mlx5_core_dev *dev, struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&dev->priv.vhca_state_notifier->n_head, nb);
+}