net/mlx5: Implement devlink enable_sriov parameter

Example usage:
  devlink dev param set pci/0000:01:00.0 name enable_sriov value {true, false} cmode permanent
  devlink dev reload pci/0000:01:00.0 action fw_activate
  echo 1 >/sys/bus/pci/devices/0000:01:00.0/remove
  echo 1 >/sys/bus/pci/rescan
  grep ^ /sys/bus/pci/devices/0000:01:00.0/sriov_*

Signed-off-by: Vlad Dumitrescu <vdumitrescu@nvidia.com>
Tested-by: Kamal Heib <kheib@redhat.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250907012953.301746-4-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 199 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/nv_param.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/nv_param.c
index 20a39483be04..ed2129843ec7 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/nv_param.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/nv_param.c
@@ -5,7 +5,11 @@
 #include "mlx5_core.h"
 
 enum {
+	MLX5_CLASS_0_CTRL_ID_NV_GLOBAL_PCI_CONF               = 0x80,
+	MLX5_CLASS_0_CTRL_ID_NV_GLOBAL_PCI_CAP                = 0x81,
 	MLX5_CLASS_0_CTRL_ID_NV_SW_OFFLOAD_CONFIG             = 0x10a,
+
+	MLX5_CLASS_3_CTRL_ID_NV_PF_PCI_CONF                   = 0x80,
 };
 
 struct mlx5_ifc_configuration_item_type_class_global_bits {
@@ -13,9 +17,18 @@ struct mlx5_ifc_configuration_item_type_class_global_bits {
 	u8         parameter_index[0x18];
 };
 
+struct mlx5_ifc_configuration_item_type_class_per_host_pf_bits {
+	u8         type_class[0x8];
+	u8         pf_index[0x6];
+	u8         pci_bus_index[0x8];
+	u8         parameter_index[0xa];
+};
+
 union mlx5_ifc_config_item_type_auto_bits {
 	struct mlx5_ifc_configuration_item_type_class_global_bits
 				configuration_item_type_class_global;
+	struct mlx5_ifc_configuration_item_type_class_per_host_pf_bits
+				configuration_item_type_class_per_host_pf;
 	u8 reserved_at_0[0x20];
 };
 
@@ -45,6 +58,45 @@ struct mlx5_ifc_mnvda_reg_bits {
 	u8         configuration_item_data[64][0x20];
 };
 
+struct mlx5_ifc_nv_global_pci_conf_bits {
+	u8         sriov_valid[0x1];
+	u8         reserved_at_1[0x10];
+	u8         per_pf_total_vf[0x1];
+	u8         reserved_at_12[0xe];
+
+	u8         sriov_en[0x1];
+	u8         reserved_at_21[0xf];
+	u8         total_vfs[0x10];
+
+	u8         reserved_at_40[0x20];
+};
+
+struct mlx5_ifc_nv_global_pci_cap_bits {
+	u8         max_vfs_per_pf_valid[0x1];
+	u8         reserved_at_1[0x13];
+	u8         per_pf_total_vf_supported[0x1];
+	u8         reserved_at_15[0xb];
+
+	u8         sriov_support[0x1];
+	u8         reserved_at_21[0xf];
+	u8         max_vfs_per_pf[0x10];
+
+	u8         reserved_at_40[0x60];
+};
+
+struct mlx5_ifc_nv_pf_pci_conf_bits {
+	u8         reserved_at_0[0x9];
+	u8         pf_total_vf_en[0x1];
+	u8         reserved_at_a[0x16];
+
+	u8         reserved_at_20[0x20];
+
+	u8         reserved_at_40[0x10];
+	u8         total_vf[0x10];
+
+	u8         reserved_at_60[0x20];
+};
+
 struct mlx5_ifc_nv_sw_offload_conf_bits {
 	u8         ip_over_vxlan_port[0x10];
 	u8         tunnel_ecn_copy_offload_disable[0x1];
@@ -216,7 +268,154 @@ mlx5_nv_param_devlink_cqe_compress_set(struct devlink *devlink, u32 id,
 	return mlx5_nv_param_write(dev, mnvda, sizeof(mnvda));
 }
 
+static int mlx5_nv_param_read_global_pci_conf(struct mlx5_core_dev *dev,
+					      void *mnvda, size_t len)
+{
+	MLX5_SET_CFG_ITEM_TYPE(global, mnvda, type_class, 0);
+	MLX5_SET_CFG_ITEM_TYPE(global, mnvda, parameter_index,
+			       MLX5_CLASS_0_CTRL_ID_NV_GLOBAL_PCI_CONF);
+	MLX5_SET_CFG_HDR_LEN(mnvda, nv_global_pci_conf);
+
+	return mlx5_nv_param_read(dev, mnvda, len);
+}
+
+static int mlx5_nv_param_read_global_pci_cap(struct mlx5_core_dev *dev,
+					     void *mnvda, size_t len)
+{
+	MLX5_SET_CFG_ITEM_TYPE(global, mnvda, type_class, 0);
+	MLX5_SET_CFG_ITEM_TYPE(global, mnvda, parameter_index,
+			       MLX5_CLASS_0_CTRL_ID_NV_GLOBAL_PCI_CAP);
+	MLX5_SET_CFG_HDR_LEN(mnvda, nv_global_pci_cap);
+
+	return mlx5_nv_param_read(dev, mnvda, len);
+}
+
+static int mlx5_nv_param_read_per_host_pf_conf(struct mlx5_core_dev *dev,
+					       void *mnvda, size_t len)
+{
+	MLX5_SET_CFG_ITEM_TYPE(per_host_pf, mnvda, type_class, 3);
+	MLX5_SET_CFG_ITEM_TYPE(per_host_pf, mnvda, parameter_index,
+			       MLX5_CLASS_3_CTRL_ID_NV_PF_PCI_CONF);
+	MLX5_SET_CFG_HDR_LEN(mnvda, nv_pf_pci_conf);
+
+	return mlx5_nv_param_read(dev, mnvda, len);
+}
+
+static int mlx5_devlink_enable_sriov_get(struct devlink *devlink, u32 id,
+					 struct devlink_param_gset_ctx *ctx)
+{
+	struct mlx5_core_dev *dev = devlink_priv(devlink);
+	u32 mnvda[MLX5_ST_SZ_DW(mnvda_reg)] = {};
+	bool sriov_en = false;
+	void *data;
+	int err;
+
+	err = mlx5_nv_param_read_global_pci_cap(dev, mnvda, sizeof(mnvda));
+	if (err)
+		return err;
+
+	data = MLX5_ADDR_OF(mnvda_reg, mnvda, configuration_item_data);
+	if (!MLX5_GET(nv_global_pci_cap, data, sriov_support)) {
+		ctx->val.vbool = false;
+		return 0;
+	}
+
+	memset(mnvda, 0, sizeof(mnvda));
+	err = mlx5_nv_param_read_global_pci_conf(dev, mnvda, sizeof(mnvda));
+	if (err)
+		return err;
+
+	data = MLX5_ADDR_OF(mnvda_reg, mnvda, configuration_item_data);
+	sriov_en = MLX5_GET(nv_global_pci_conf, data, sriov_en);
+	if (!MLX5_GET(nv_global_pci_conf, data, per_pf_total_vf)) {
+		ctx->val.vbool = sriov_en;
+		return 0;
+	}
+
+	/* SRIOV is per PF */
+	memset(mnvda, 0, sizeof(mnvda));
+	err = mlx5_nv_param_read_per_host_pf_conf(dev, mnvda, sizeof(mnvda));
+	if (err)
+		return err;
+
+	data = MLX5_ADDR_OF(mnvda_reg, mnvda, configuration_item_data);
+	ctx->val.vbool = sriov_en &&
+			 MLX5_GET(nv_pf_pci_conf, data, pf_total_vf_en);
+	return 0;
+}
+
+static int mlx5_devlink_enable_sriov_set(struct devlink *devlink, u32 id,
+					 struct devlink_param_gset_ctx *ctx,
+					 struct netlink_ext_ack *extack)
+{
+	struct mlx5_core_dev *dev = devlink_priv(devlink);
+	u32 mnvda[MLX5_ST_SZ_DW(mnvda_reg)] = {};
+	bool per_pf_support;
+	void *cap, *data;
+	int err;
+
+	err = mlx5_nv_param_read_global_pci_cap(dev, mnvda, sizeof(mnvda));
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Failed to read global PCI capability");
+		return err;
+	}
+
+	cap = MLX5_ADDR_OF(mnvda_reg, mnvda, configuration_item_data);
+	per_pf_support = MLX5_GET(nv_global_pci_cap, cap,
+				  per_pf_total_vf_supported);
+
+	if (!MLX5_GET(nv_global_pci_cap, cap, sriov_support)) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "SRIOV is not supported on this device");
+		return -EOPNOTSUPP;
+	}
+
+	if (!per_pf_support) {
+		/* We don't allow global SRIOV setting on per PF devlink */
+		NL_SET_ERR_MSG_MOD(extack,
+				   "SRIOV is not per PF on this device");
+		return -EOPNOTSUPP;
+	}
+
+	memset(mnvda, 0, sizeof(mnvda));
+	err = mlx5_nv_param_read_global_pci_conf(dev, mnvda, sizeof(mnvda));
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Unable to read global PCI configuration");
+		return err;
+	}
+
+	data = MLX5_ADDR_OF(mnvda_reg, mnvda, configuration_item_data);
+
+	/* setup per PF sriov mode */
+	MLX5_SET(nv_global_pci_conf, data, sriov_valid, 1);
+	MLX5_SET(nv_global_pci_conf, data, sriov_en, 1);
+	MLX5_SET(nv_global_pci_conf, data, per_pf_total_vf, 1);
+
+	err = mlx5_nv_param_write(dev, mnvda, sizeof(mnvda));
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Unable to write global PCI configuration");
+		return err;
+	}
+
+	/* enable/disable sriov on this PF */
+	memset(mnvda, 0, sizeof(mnvda));
+	err = mlx5_nv_param_read_per_host_pf_conf(dev, mnvda, sizeof(mnvda));
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Unable to read per host PF configuration");
+		return err;
+	}
+	MLX5_SET(nv_pf_pci_conf, data, pf_total_vf_en, ctx->val.vbool);
+	return mlx5_nv_param_write(dev, mnvda, sizeof(mnvda));
+}
+
 static const struct devlink_param mlx5_nv_param_devlink_params[] = {
+	DEVLINK_PARAM_GENERIC(ENABLE_SRIOV, BIT(DEVLINK_PARAM_CMODE_PERMANENT),
+			      mlx5_devlink_enable_sriov_get,
+			      mlx5_devlink_enable_sriov_set, NULL),
 	DEVLINK_PARAM_DRIVER(MLX5_DEVLINK_PARAM_ID_CQE_COMPRESSION_TYPE,
 			     "cqe_compress_type", DEVLINK_PARAM_TYPE_STRING,
 			     BIT(DEVLINK_PARAM_CMODE_PERMANENT),