net/mlx4_core: Add basic support for QP max-rate limiting

Add the low-level device commands and definitions used for QP max-rate limiting.

This is done through the following elements:

  - read rate-limit device caps in QUERY_DEV_CAP: number of different
    rates and the min/max rates in Kbs/Mbs/Gbs units

  - enhance the QP context struct to contain rate limit units and value

  - allow to do run time rate-limit setting to QPs through the
    update-qp firmware command

  - QP rate-limiting is disallowed for VFs

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 27 insertions, 4 deletions

diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index 1cc54822b931..4550c67b92e4 100644
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -205,6 +205,7 @@ enum {
         MLX4_DEV_CAP_FLAG2_RECOVERABLE_ERROR_EVENT = 1LL << 20,
         MLX4_DEV_CAP_FLAG2_PORT_REMAP           = 1LL <<  21,
         MLX4_DEV_CAP_FLAG2_QCN                  = 1LL <<  22,
+        MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT        = 1LL <<  23
 };
 
 enum {
@@ -450,6 +451,21 @@ enum mlx4_module_id {
         MLX4_MODULE_ID_QSFP28           = 0x11,
 };
 
+enum { /* rl */
+        MLX4_QP_RATE_LIMIT_NONE         = 0,
+        MLX4_QP_RATE_LIMIT_KBS          = 1,
+        MLX4_QP_RATE_LIMIT_MBS          = 2,
+        MLX4_QP_RATE_LIMIT_GBS          = 3
+};
+
+struct mlx4_rate_limit_caps {
+        u16     num_rates; /* Number of different rates */
+        u8      min_unit;
+        u16     min_val;
+        u8      max_unit;
+        u16     max_val;
+};
+
 static inline u64 mlx4_fw_ver(u64 major, u64 minor, u64 subminor)
 {
         return (major << 32) | (minor << 16) | subminor;
@@ -565,6 +581,7 @@ struct mlx4_caps {
         u32                     dmfs_high_rate_qpn_base;
         u32                     dmfs_high_rate_qpn_range;
         u32                     vf_caps;
+        struct mlx4_rate_limit_caps rl_caps;
 };
 
 struct mlx4_buf_list {
diff --git a/include/linux/mlx4/qp.h b/include/linux/mlx4/qp.h
index 551f85456c11..1023ebe035b7 100644
--- a/include/linux/mlx4/qp.h
+++ b/include/linux/mlx4/qp.h
@@ -207,14 +207,16 @@ struct mlx4_qp_context {
         __be32                  msn;
         __be16                  rq_wqe_counter;
         __be16                  sq_wqe_counter;
-        u32                     reserved3[2];
+        u32                     reserved3;
+        __be16                  rate_limit_params;
+        __be16                  reserved4;
         __be32                  param3;
         __be32                  nummmcpeers_basemkey;
         u8                      log_page_size;
-        u8                      reserved4[2];
+        u8                      reserved5[2];
         u8                      mtt_base_addr_h;
         __be32                  mtt_base_addr_l;
-        u32                     reserved5[10];
+        u32                     reserved6[10];
 };
 
 struct mlx4_update_qp_context {
@@ -229,6 +231,7 @@ struct mlx4_update_qp_context {
 enum {
         MLX4_UPD_QP_MASK_PM_STATE       = 32,
         MLX4_UPD_QP_MASK_VSD            = 33,
+        MLX4_UPD_QP_MASK_RATE_LIMIT     = 35,
 };
 
 enum {
@@ -428,7 +431,8 @@ struct mlx4_wqe_inline_seg {
 enum mlx4_update_qp_attr {
         MLX4_UPDATE_QP_SMAC             = 1 << 0,
         MLX4_UPDATE_QP_VSD              = 1 << 1,
-        MLX4_UPDATE_QP_SUPPORTED_ATTRS  = (1 << 2) - 1
+        MLX4_UPDATE_QP_RATE_LIMIT       = 1 << 2,
+        MLX4_UPDATE_QP_SUPPORTED_ATTRS  = (1 << 3) - 1
 };
 
 enum mlx4_update_qp_params_flags {
@@ -438,6 +442,8 @@ enum mlx4_update_qp_params_flags {
 struct mlx4_update_qp_params {
         u8      smac_index;
         u32     flags;
+        u16     rate_unit;
+        u16     rate_val;
 };
 
 int mlx4_update_qp(struct mlx4_dev *dev, u32 qpn,