/* * Copyright (c) 2018, Mellanox Technologies. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "port_buffer.h" int mlx5e_port_query_buffer(struct mlx5e_priv *priv, struct mlx5e_port_buffer *port_buffer) { u16 port_buff_cell_sz = priv->dcbx.port_buff_cell_sz; struct mlx5_core_dev *mdev = priv->mdev; int sz = MLX5_ST_SZ_BYTES(pbmc_reg); u32 total_used = 0; void *buffer; void *out; int err; int i; out = kzalloc(sz, GFP_KERNEL); if (!out) return -ENOMEM; err = mlx5e_port_query_pbmc(mdev, out); if (err) goto out; for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) { buffer = MLX5_ADDR_OF(pbmc_reg, out, buffer[i]); port_buffer->buffer[i].lossy = MLX5_GET(bufferx_reg, buffer, lossy); port_buffer->buffer[i].epsb = MLX5_GET(bufferx_reg, buffer, epsb); port_buffer->buffer[i].size = MLX5_GET(bufferx_reg, buffer, size) * port_buff_cell_sz; port_buffer->buffer[i].xon = MLX5_GET(bufferx_reg, buffer, xon_threshold) * port_buff_cell_sz; port_buffer->buffer[i].xoff = MLX5_GET(bufferx_reg, buffer, xoff_threshold) * port_buff_cell_sz; total_used += port_buffer->buffer[i].size; netdev_dbg(priv->netdev, "buffer %d: size=%d, xon=%d, xoff=%d, epsb=%d, lossy=%d\n", i, port_buffer->buffer[i].size, port_buffer->buffer[i].xon, port_buffer->buffer[i].xoff, port_buffer->buffer[i].epsb, port_buffer->buffer[i].lossy); } port_buffer->internal_buffers_size = 0; for (i = MLX5E_MAX_NETWORK_BUFFER; i < MLX5E_TOTAL_BUFFERS; i++) { buffer = MLX5_ADDR_OF(pbmc_reg, out, buffer[i]); port_buffer->internal_buffers_size += MLX5_GET(bufferx_reg, buffer, size) * port_buff_cell_sz; } port_buffer->port_buffer_size = MLX5_GET(pbmc_reg, out, port_buffer_size) * port_buff_cell_sz; port_buffer->headroom_size = total_used; port_buffer->spare_buffer_size = port_buffer->port_buffer_size - port_buffer->internal_buffers_size - port_buffer->headroom_size; netdev_dbg(priv->netdev, "total buffer size=%u, headroom buffer size=%u, internal buffers size=%u, spare buffer size=%u\n", port_buffer->port_buffer_size, port_buffer->headroom_size, port_buffer->internal_buffers_size, port_buffer->spare_buffer_size); out: kfree(out); return err; } struct mlx5e_buffer_pool { u32 infi_size; u32 size; u32 buff_occupancy; }; static int mlx5e_port_query_pool(struct mlx5_core_dev *mdev, struct mlx5e_buffer_pool *buffer_pool, u32 desc, u8 dir, u8 pool_idx) { u32 out[MLX5_ST_SZ_DW(sbpr_reg)] = {}; int err; err = mlx5e_port_query_sbpr(mdev, desc, dir, pool_idx, out, sizeof(out)); if (err) return err; buffer_pool->size = MLX5_GET(sbpr_reg, out, size); buffer_pool->infi_size = MLX5_GET(sbpr_reg, out, infi_size); buffer_pool->buff_occupancy = MLX5_GET(sbpr_reg, out, buff_occupancy); return err; } enum { MLX5_INGRESS_DIR = 0, MLX5_EGRESS_DIR = 1, }; enum { MLX5_LOSSY_POOL = 0, MLX5_LOSSLESS_POOL = 1, }; /* No limit on usage of shared buffer pool (max_buff=0) */ #define MLX5_SB_POOL_NO_THRESHOLD 0 /* Shared buffer pool usage threshold when calculated * dynamically in alpha units. alpha=13 is equivalent to * HW_alpha of [(1/128) * 2 ^ (alpha-1)] = 32, where HW_alpha * equates to the following portion of the shared buffer pool: * [32 / (1 + n * 32)] While *n* is the number of buffers * that are using the shared buffer pool. */ #define MLX5_SB_POOL_THRESHOLD 13 /* Shared buffer class management parameters */ struct mlx5_sbcm_params { u8 pool_idx; u8 max_buff; u8 infi_size; }; static const struct mlx5_sbcm_params sbcm_default = { .pool_idx = MLX5_LOSSY_POOL, .max_buff = MLX5_SB_POOL_NO_THRESHOLD, .infi_size = 0, }; static const struct mlx5_sbcm_params sbcm_lossy = { .pool_idx = MLX5_LOSSY_POOL, .max_buff = MLX5_SB_POOL_NO_THRESHOLD, .infi_size = 1, }; static const struct mlx5_sbcm_params sbcm_lossless = { .pool_idx = MLX5_LOSSLESS_POOL, .max_buff = MLX5_SB_POOL_THRESHOLD, .infi_size = 0, }; static const struct mlx5_sbcm_params sbcm_lossless_no_threshold = { .pool_idx = MLX5_LOSSLESS_POOL, .max_buff = MLX5_SB_POOL_NO_THRESHOLD, .infi_size = 1, }; /** * select_sbcm_params() - selects the shared buffer pool configuration * * @buffer: port buffer to retrieve params of * @lossless_buff_count: number of lossless buffers in total * * The selection is based on the following rules: * 1. If buffer size is 0, no shared buffer pool is used. * 2. If buffer is lossy, use lossy shared buffer pool. * 3. If there are more than 1 lossless buffers, use lossless shared buffer pool * with threshold. * 4. If there is only 1 lossless buffer, use lossless shared buffer pool * without threshold. * * @return const struct mlx5_sbcm_params* selected values */ static const struct mlx5_sbcm_params * select_sbcm_params(struct mlx5e_bufferx_reg *buffer, u8 lossless_buff_count) { if (buffer->size == 0) return &sbcm_default; if (buffer->lossy) return &sbcm_lossy; if (lossless_buff_count > 1) return &sbcm_lossless; return &sbcm_lossless_no_threshold; } static int port_update_pool_cfg(struct mlx5_core_dev *mdev, struct mlx5e_port_buffer *port_buffer) { const struct mlx5_sbcm_params *p; u8 lossless_buff_count = 0; int err; int i; if (!MLX5_CAP_GEN(mdev, sbcam_reg)) return 0; for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) lossless_buff_count += ((port_buffer->buffer[i].size) && (!(port_buffer->buffer[i].lossy))); for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) { p = select_sbcm_params(&port_buffer->buffer[i], lossless_buff_count); err = mlx5e_port_set_sbcm(mdev, 0, i, MLX5_INGRESS_DIR, p->infi_size, p->max_buff, p->pool_idx); if (err) return err; } return 0; } static int port_update_shared_buffer(struct mlx5_core_dev *mdev, u32 current_headroom_size, u32 new_headroom_size) { struct mlx5e_buffer_pool lossless_ipool; struct mlx5e_buffer_pool lossy_epool; u32 lossless_ipool_size; u32 shared_buffer_size; u32 total_buffer_size; u32 lossy_epool_size; int err; if (!MLX5_CAP_GEN(mdev, sbcam_reg)) return 0; err = mlx5e_port_query_pool(mdev, &lossy_epool, 0, MLX5_EGRESS_DIR, MLX5_LOSSY_POOL); if (err) return err; err = mlx5e_port_query_pool(mdev, &lossless_ipool, 0, MLX5_INGRESS_DIR, MLX5_LOSSLESS_POOL); if (err) return err; total_buffer_size = current_headroom_size + lossy_epool.size + lossless_ipool.size; shared_buffer_size = total_buffer_size - new_headroom_size; if (shared_buffer_size < 4) { pr_err("Requested port buffer is too large, not enough space left for shared buffer\n"); return -EINVAL; } /* Total shared buffer size is split in a ratio of 3:1 between * lossy and lossless pools respectively. */ lossy_epool_size = (shared_buffer_size / 4) * 3; lossless_ipool_size = shared_buffer_size / 4; mlx5e_port_set_sbpr(mdev, 0, MLX5_EGRESS_DIR, MLX5_LOSSY_POOL, 0, lossy_epool_size); mlx5e_port_set_sbpr(mdev, 0, MLX5_INGRESS_DIR, MLX5_LOSSLESS_POOL, 0, lossless_ipool_size); return 0; } static int port_set_buffer(struct mlx5e_priv *priv, struct mlx5e_port_buffer *port_buffer) { u16 port_buff_cell_sz = priv->dcbx.port_buff_cell_sz; struct mlx5_core_dev *mdev = priv->mdev; int sz = MLX5_ST_SZ_BYTES(pbmc_reg); u32 new_headroom_size = 0; u32 current_headroom_size; void *in; int err; int i; current_headroom_size = port_buffer->headroom_size; in = kzalloc(sz, GFP_KERNEL); if (!in) return -ENOMEM; err = mlx5e_port_query_pbmc(mdev, in); if (err) goto out; for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) { void *buffer = MLX5_ADDR_OF(pbmc_reg, in, buffer[i]); u64 size = port_buffer->buffer[i].size; u64 xoff = port_buffer->buffer[i].xoff; u64 xon = port_buffer->buffer[i].xon; new_headroom_size += size; do_div(size, port_buff_cell_sz); do_div(xoff, port_buff_cell_sz); do_div(xon, port_buff_cell_sz); MLX5_SET(bufferx_reg, buffer, size, size); MLX5_SET(bufferx_reg, buffer, lossy, port_buffer->buffer[i].lossy); MLX5_SET(bufferx_reg, buffer, xoff_threshold, xoff); MLX5_SET(bufferx_reg, buffer, xon_threshold, xon); } new_headroom_size /= port_buff_cell_sz; current_headroom_size /= port_buff_cell_sz; err = port_update_shared_buffer(priv->mdev, current_headroom_size, new_headroom_size); if (err) goto out; err = port_update_pool_cfg(priv->mdev, port_buffer); if (err) goto out; err = mlx5e_port_set_pbmc(mdev, in); out: kfree(in); return err; } /* xoff = ((301+2.16 * len [m]) * speed [Gbps] + 2.72 MTU [B]) * minimum speed value is 40Gbps */ static u32 calculate_xoff(struct mlx5e_priv *priv, unsigned int mtu) { u32 speed; u32 xoff; int err; err = mlx5e_port_linkspeed(priv->mdev, &speed); if (err) speed = SPEED_40000; speed = max_t(u32, speed, SPEED_40000); xoff = (301 + 216 * priv->dcbx.cable_len / 100) * speed / 1000 + 272 * mtu / 100; netdev_dbg(priv->netdev, "%s: xoff=%d\n", __func__, xoff); return xoff; } static int update_xoff_threshold(struct mlx5e_port_buffer *port_buffer, u32 xoff, unsigned int max_mtu, u16 port_buff_cell_sz) { int i; for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) { if (port_buffer->buffer[i].lossy) { port_buffer->buffer[i].xoff = 0; port_buffer->buffer[i].xon = 0; continue; } if (port_buffer->buffer[i].size < (xoff + max_mtu + port_buff_cell_sz)) { pr_err("buffer_size[%d]=%d is not enough for lossless buffer\n", i, port_buffer->buffer[i].size); return -ENOMEM; } port_buffer->buffer[i].xoff = port_buffer->buffer[i].size - xoff; port_buffer->buffer[i].xon = port_buffer->buffer[i].xoff - max_mtu; } return 0; } /** * update_buffer_lossy - Update buffer configuration based on pfc * @mdev: port function core device * @max_mtu: netdev's max_mtu * @pfc_en: current pfc configuration * @buffer: current prio to buffer mapping * @xoff: xoff value * @port_buff_cell_sz: port buffer cell_size * @port_buffer: port receive buffer configuration * @change: * * Update buffer configuration based on pfc configuration and * priority to buffer mapping. * Buffer's lossy bit is changed to: * lossless if there is at least one PFC enabled priority * mapped to this buffer lossy if all priorities mapped to * this buffer are PFC disabled * * @return: 0 if no error, * sets change to true if buffer configuration was modified. */ static int update_buffer_lossy(struct mlx5_core_dev *mdev, unsigned int max_mtu, u8 pfc_en, u8 *buffer, u32 xoff, u16 port_buff_cell_sz, struct mlx5e_port_buffer *port_buffer, bool *change) { bool changed = false; u8 lossy_count; u8 prio_count; u8 lossy; int prio; int err; int i; for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) { prio_count = 0; lossy_count = 0; for (prio = 0; prio < MLX5E_MAX_PRIORITY; prio++) { if (buffer[prio] != i) continue; prio_count++; lossy_count += !(pfc_en & (1 << prio)); } if (lossy_count == prio_count) lossy = 1; else /* lossy_count < prio_count */ lossy = 0; if (lossy != port_buffer->buffer[i].lossy) { port_buffer->buffer[i].lossy = lossy; changed = true; } } if (changed) { err = update_xoff_threshold(port_buffer, xoff, max_mtu, port_buff_cell_sz); if (err) return err; err = port_update_pool_cfg(mdev, port_buffer); if (err) return err; *change = true; } return 0; } static int fill_pfc_en(struct mlx5_core_dev *mdev, u8 *pfc_en) { u32 g_rx_pause, g_tx_pause; int err; err = mlx5_query_port_pause(mdev, &g_rx_pause, &g_tx_pause); if (err) return err; /* If global pause enabled, set all active buffers to lossless. * Otherwise, check PFC setting. */ if (g_rx_pause || g_tx_pause) *pfc_en = 0xff; else err = mlx5_query_port_pfc(mdev, pfc_en, NULL); return err; } #define MINIMUM_MAX_MTU 9216 int mlx5e_port_manual_buffer_config(struct mlx5e_priv *priv, u32 change, unsigned int mtu, struct ieee_pfc *pfc, u32 *buffer_size, u8 *prio2buffer) { u16 port_buff_cell_sz = priv->dcbx.port_buff_cell_sz; struct net_device *netdev = priv->netdev; struct mlx5e_port_buffer port_buffer; u32 xoff = calculate_xoff(priv, mtu); bool update_prio2buffer = false; u8 buffer[MLX5E_MAX_PRIORITY]; bool update_buffer = false; unsigned int max_mtu; u32 total_used = 0; u8 curr_pfc_en; int err; int i; netdev_dbg(netdev, "%s: change=%x\n", __func__, change); max_mtu = max_t(unsigned int, priv->netdev->max_mtu, MINIMUM_MAX_MTU); err = mlx5e_port_query_buffer(priv, &port_buffer); if (err) return err; if (change & MLX5E_PORT_BUFFER_CABLE_LEN) { update_buffer = true; err = update_xoff_threshold(&port_buffer, xoff, max_mtu, port_buff_cell_sz); if (err) return err; } if (change & MLX5E_PORT_BUFFER_PFC) { netdev_dbg(netdev, "%s: requested PFC per priority bitmask: 0x%x\n", __func__, pfc->pfc_en); err = mlx5e_port_query_priority2buffer(priv->mdev, buffer); if (err) return err; err = update_buffer_lossy(priv->mdev, max_mtu, pfc->pfc_en, buffer, xoff, port_buff_cell_sz, &port_buffer, &update_buffer); if (err) return err; } if (change & MLX5E_PORT_BUFFER_PRIO2BUFFER) { update_prio2buffer = true; for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) netdev_dbg(priv->netdev, "%s: requested to map prio[%d] to buffer %d\n", __func__, i, prio2buffer[i]); err = fill_pfc_en(priv->mdev, &curr_pfc_en); if (err) return err; err = update_buffer_lossy(priv->mdev, max_mtu, curr_pfc_en, prio2buffer, xoff, port_buff_cell_sz, &port_buffer, &update_buffer); if (err) return err; } if (change & MLX5E_PORT_BUFFER_SIZE) { for (i = 0; i < MLX5E_MAX_NETWORK_BUFFER; i++) { netdev_dbg(priv->netdev, "%s: buffer[%d]=%d\n", __func__, i, buffer_size[i]); if (!port_buffer.buffer[i].lossy && !buffer_size[i]) { netdev_dbg(priv->netdev, "%s: lossless buffer[%d] size cannot be zero\n", __func__, i); return -EINVAL; } port_buffer.buffer[i].size = buffer_size[i]; total_used += buffer_size[i]; } netdev_dbg(priv->netdev, "%s: total buffer requested=%d\n", __func__, total_used); if (total_used > port_buffer.headroom_size && (total_used - port_buffer.headroom_size) > port_buffer.spare_buffer_size) return -EINVAL; update_buffer = true; err = update_xoff_threshold(&port_buffer, xoff, max_mtu, port_buff_cell_sz); if (err) return err; } /* Need to update buffer configuration if xoff value is changed */ if (!update_buffer && xoff != priv->dcbx.xoff) { update_buffer = true; err = update_xoff_threshold(&port_buffer, xoff, max_mtu, port_buff_cell_sz); if (err) return err; } priv->dcbx.xoff = xoff; /* Apply the settings */ if (update_buffer) { err = port_set_buffer(priv, &port_buffer); if (err) return err; } if (update_prio2buffer) err = mlx5e_port_set_priority2buffer(priv->mdev, prio2buffer); return err; }