diff options
Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx5/core/en/port_buffer.c')
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx5/core/en/port_buffer.c | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/port_buffer.c b/drivers/net/ethernet/mellanox/mlx5/core/en/port_buffer.c new file mode 100644 index 0000000000000..c047da8752daa --- /dev/null +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/port_buffer.c @@ -0,0 +1,327 @@ +/* + * 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) +{ + 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_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) << MLX5E_BUFFER_CELL_SHIFT; + port_buffer->buffer[i].xon = + MLX5_GET(bufferx_reg, buffer, xon_threshold) << MLX5E_BUFFER_CELL_SHIFT; + port_buffer->buffer[i].xoff = + MLX5_GET(bufferx_reg, buffer, xoff_threshold) << MLX5E_BUFFER_CELL_SHIFT; + total_used += port_buffer->buffer[i].size; + + mlx5e_dbg(HW, priv, "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->port_buffer_size = + MLX5_GET(pbmc_reg, out, port_buffer_size) << MLX5E_BUFFER_CELL_SHIFT; + port_buffer->spare_buffer_size = + port_buffer->port_buffer_size - total_used; + + mlx5e_dbg(HW, priv, "total buffer size=%d, spare buffer size=%d\n", + port_buffer->port_buffer_size, + port_buffer->spare_buffer_size); +out: + kfree(out); + return err; +} + +static int port_set_buffer(struct mlx5e_priv *priv, + struct mlx5e_port_buffer *port_buffer) +{ + struct mlx5_core_dev *mdev = priv->mdev; + int sz = MLX5_ST_SZ_BYTES(pbmc_reg); + void *buffer; + void *in; + int err; + int i; + + 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_BUFFER; i++) { + buffer = MLX5_ADDR_OF(pbmc_reg, in, buffer[i]); + + MLX5_SET(bufferx_reg, buffer, size, + port_buffer->buffer[i].size >> MLX5E_BUFFER_CELL_SHIFT); + MLX5_SET(bufferx_reg, buffer, lossy, + port_buffer->buffer[i].lossy); + MLX5_SET(bufferx_reg, buffer, xoff_threshold, + port_buffer->buffer[i].xoff >> MLX5E_BUFFER_CELL_SHIFT); + MLX5_SET(bufferx_reg, buffer, xon_threshold, + port_buffer->buffer[i].xon >> MLX5E_BUFFER_CELL_SHIFT); + } + + err = mlx5e_port_set_pbmc(mdev, in); +out: + kfree(in); + return err; +} + +/* xoff = ((301+2.16 * len [m]) * speed [Gbps] + 2.72 MTU [B]) */ +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) + return 0; + + xoff = (301 + 216 * priv->dcbx.cable_len / 100) * speed / 1000 + 272 * mtu / 100; + + mlx5e_dbg(HW, priv, "%s: xoff=%d\n", __func__, xoff); + return xoff; +} + +static int update_xoff_threshold(struct mlx5e_port_buffer *port_buffer, + u32 xoff, unsigned int mtu) +{ + int i; + + for (i = 0; i < MLX5E_MAX_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 + mtu + (1 << MLX5E_BUFFER_CELL_SHIFT))) + return -ENOMEM; + + port_buffer->buffer[i].xoff = port_buffer->buffer[i].size - xoff; + port_buffer->buffer[i].xon = port_buffer->buffer[i].xoff - mtu; + } + + return 0; +} + +/** + * update_buffer_lossy() + * mtu: device's MTU + * pfc_en: <input> current pfc configuration + * buffer: <input> current prio to buffer mapping + * xoff: <input> xoff value + * port_buffer: <output> port receive buffer configuration + * change: <output> + * + * Update buffer configuration based on pfc configuraiton 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: + * Return 0 if no error. + * Set change to true if buffer configuration is modified. + */ +static int update_buffer_lossy(unsigned int mtu, + u8 pfc_en, u8 *buffer, u32 xoff, + 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_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, mtu); + if (err) + return err; + + *change = true; + } + + return 0; +} + +int mlx5e_port_manual_buffer_config(struct mlx5e_priv *priv, + u32 change, unsigned int mtu, + struct ieee_pfc *pfc, + u32 *buffer_size, + u8 *prio2buffer) +{ + 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; + u32 total_used = 0; + u8 curr_pfc_en; + int err; + int i; + + mlx5e_dbg(HW, priv, "%s: change=%x\n", __func__, change); + + 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, mtu); + if (err) + return err; + } + + if (change & MLX5E_PORT_BUFFER_PFC) { + err = mlx5e_port_query_priority2buffer(priv->mdev, buffer); + if (err) + return err; + + err = update_buffer_lossy(mtu, pfc->pfc_en, buffer, xoff, + &port_buffer, &update_buffer); + if (err) + return err; + } + + if (change & MLX5E_PORT_BUFFER_PRIO2BUFFER) { + update_prio2buffer = true; + err = mlx5_query_port_pfc(priv->mdev, &curr_pfc_en, NULL); + if (err) + return err; + + err = update_buffer_lossy(mtu, curr_pfc_en, prio2buffer, xoff, + &port_buffer, &update_buffer); + if (err) + return err; + } + + if (change & MLX5E_PORT_BUFFER_SIZE) { + for (i = 0; i < MLX5E_MAX_BUFFER; i++) { + mlx5e_dbg(HW, priv, "%s: buffer[%d]=%d\n", __func__, i, buffer_size[i]); + if (!port_buffer.buffer[i].lossy && !buffer_size[i]) { + mlx5e_dbg(HW, priv, "%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]; + } + + mlx5e_dbg(HW, priv, "%s: total buffer requested=%d\n", __func__, total_used); + + if (total_used > port_buffer.port_buffer_size) + return -EINVAL; + + update_buffer = true; + err = update_xoff_threshold(&port_buffer, xoff, mtu); + 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, mtu); + 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; +} |