net/mlx5: Manage TC arbiter nodes and implement full support for tc-bw

net/mlx5: Manage TC arbiter nodes and implement full support for tc-bw

Introduce support for managing Traffic Class (TC) arbiter nodes and
associated vports TC nodes within the E-Switch QoS hierarchy. This
patch adds support for the new scheduling node type,
`SCHED_NODE_TYPE_VPORTS_TC_TSAR`, and implements full support for
setting tc-bw on both vports and nodes.

Key changes include:

- Introduced the new scheduling node type,
  `SCHED_NODE_TYPE_VPORTS_TC_TSAR`, for managing vports within the TC
  arbiter node.

- New helper functions for creating and destroying vports TC nodes
  under the TC arbiter.

- Updated the minimum rate normalization function to skip nodes of type
  `SCHED_NODE_TYPE_VPORTS_TC_TSAR`. Vports TC TSARs have bandwidth
  shares configured on them but not minimum rates, so their `min_rate`
  cannot be normalized.

- Implementation of `esw_qos_tc_arbiter_scheduling_setup()` and
  `esw_qos_tc_arbiter_scheduling_teardown()` for initializing and
  cleaning up TC arbiter scheduling elements. These functions now fully
  support tc-bw configuration on TC arbiter nodes.

- Introduced a new helper `esw_qos_calculate_tc_bw_divider()` to
  compute the total TC bandwidth share, which is used as a divider for
  normalizing each TC's share.

- Added `esw_qos_tc_arbiter_get_bw_shares()` and
  `esw_qos_set_tc_arbiter_bw_shares()` to handle the settings of
  bandwidth shares for vports traffic class TSARs.

- `esw_qos_set_tc_arbiter_bw_shares()` normalizes  each TC share based
  on the total and the firmware's maximum allowed TSAR bandwidth share.

- Refactored `mlx5_esw_devlink_rate_node_tc_bw_set()` and
  `mlx5_esw_devlink_rate_leaf_tc_bw_set()` to fully support configuring
  tc-bw on devlink rate nodes and vports, respectively.

- Refactored `mlx5_esw_qos_node_update_parent()` to ensure that tc-bw
  configuration remains compatible with setting a parent on a rate
  node, preserving level hierarchy functionality.

- Refactored `esw_qos_calc_bw_share()` to generalize its input so it
  can be used for both minimum rate and bandwidth share calculations.

Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Link: https://patch.msgid.link/20250629142138.361537-8-mbloch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>