/*
 * Copyright (c) 2014, Mellanox Technologies inc.  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 <linux/pci.h>
#include <linux/mlx5/driver.h>
#include <linux/mlx5/vport.h>
#include "mlx5_core.h"
#include "eswitch.h"

bool mlx5_sriov_is_enabled(struct mlx5_core_dev *dev)
{
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;

        return !!sriov->num_vfs;
}

static int sriov_restore_guids(struct mlx5_core_dev *dev, int vf)
{
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;
        struct mlx5_hca_vport_context *in;
        int err = 0;

        /* Restore sriov guid and policy settings */
        if (sriov->vfs_ctx[vf].node_guid ||
            sriov->vfs_ctx[vf].port_guid ||
            sriov->vfs_ctx[vf].policy != MLX5_POLICY_INVALID) {
                in = kzalloc(sizeof(*in), GFP_KERNEL);
                if (!in)
                        return -ENOMEM;

                in->node_guid = sriov->vfs_ctx[vf].node_guid;
                in->port_guid = sriov->vfs_ctx[vf].port_guid;
                in->policy = sriov->vfs_ctx[vf].policy;
                in->field_select =
                        !!(in->port_guid) * MLX5_HCA_VPORT_SEL_PORT_GUID |
                        !!(in->node_guid) * MLX5_HCA_VPORT_SEL_NODE_GUID |
                        !!(in->policy) * MLX5_HCA_VPORT_SEL_STATE_POLICY;

                err = mlx5_core_modify_hca_vport_context(dev, 1, 1, vf + 1, in);
                if (err)
                        mlx5_core_warn(dev, "modify vport context failed, unable to restore VF %d settings\n", vf);

                kfree(in);
        }

        return err;
}

static int mlx5_device_enable_sriov(struct mlx5_core_dev *dev, int num_vfs)
{
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;
        int err;
        int vf;

        if (sriov->enabled_vfs) {
                mlx5_core_warn(dev,
                               "failed to enable SRIOV on device, already enabled with %d vfs\n",
                               sriov->enabled_vfs);
                return -EBUSY;
        }

        if (!MLX5_ESWITCH_MANAGER(dev))
                goto enable_vfs_hca;

        err = mlx5_eswitch_enable_sriov(dev->priv.eswitch, num_vfs, SRIOV_LEGACY);
        if (err) {
                mlx5_core_warn(dev,
                               "failed to enable eswitch SRIOV (%d)\n", err);
                return err;
        }

enable_vfs_hca:
        for (vf = 0; vf < num_vfs; vf++) {
                err = mlx5_core_enable_hca(dev, vf + 1);
                if (err) {
                        mlx5_core_warn(dev, "failed to enable VF %d (%d)\n", vf, err);
                        continue;
                }
                sriov->vfs_ctx[vf].enabled = 1;
                sriov->enabled_vfs++;
                if (MLX5_CAP_GEN(dev, port_type) == MLX5_CAP_PORT_TYPE_IB) {
                        err = sriov_restore_guids(dev, vf);
                        if (err) {
                                mlx5_core_warn(dev,
                                               "failed to restore VF %d settings, err %d\n",
                                               vf, err);
                                continue;
                        }
                }
                mlx5_core_dbg(dev, "successfully enabled VF* %d\n", vf);
        }

        return 0;
}

static void mlx5_device_disable_sriov(struct mlx5_core_dev *dev)
{
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;
        int err;
        int vf;

        if (!sriov->enabled_vfs)
                goto out;

        for (vf = 0; vf < sriov->num_vfs; vf++) {
                if (!sriov->vfs_ctx[vf].enabled)
                        continue;
                err = mlx5_core_disable_hca(dev, vf + 1);
                if (err) {
                        mlx5_core_warn(dev, "failed to disable VF %d\n", vf);
                        continue;
                }
                sriov->vfs_ctx[vf].enabled = 0;
                sriov->enabled_vfs--;
        }

out:
        if (MLX5_ESWITCH_MANAGER(dev))
                mlx5_eswitch_disable_sriov(dev->priv.eswitch);

        if (mlx5_wait_for_vf_pages(dev))
                mlx5_core_warn(dev, "timeout reclaiming VFs pages\n");
}

static int mlx5_pci_enable_sriov(struct pci_dev *pdev, int num_vfs)
{
        struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
        int err = 0;

        if (pci_num_vf(pdev)) {
                mlx5_core_warn(dev, "Unable to enable pci sriov, already enabled\n");
                return -EBUSY;
        }

        err = pci_enable_sriov(pdev, num_vfs);
        if (err)
                mlx5_core_warn(dev, "pci_enable_sriov failed : %d\n", err);

        return err;
}

static void mlx5_pci_disable_sriov(struct pci_dev *pdev)
{
        pci_disable_sriov(pdev);
}

static int mlx5_sriov_enable(struct pci_dev *pdev, int num_vfs)
{
        struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;
        int err = 0;

        err = mlx5_device_enable_sriov(dev, num_vfs);
        if (err) {
                mlx5_core_warn(dev, "mlx5_device_enable_sriov failed : %d\n", err);
                return err;
        }

        err = mlx5_pci_enable_sriov(pdev, num_vfs);
        if (err) {
                mlx5_core_warn(dev, "mlx5_pci_enable_sriov failed : %d\n", err);
                mlx5_device_disable_sriov(dev);
                return err;
        }

        sriov->num_vfs = num_vfs;

        return 0;
}

static void mlx5_sriov_disable(struct pci_dev *pdev)
{
        struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;

        mlx5_pci_disable_sriov(pdev);
        mlx5_device_disable_sriov(dev);
        sriov->num_vfs = 0;
}

int mlx5_core_sriov_configure(struct pci_dev *pdev, int num_vfs)
{
        struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
        int err = 0;

        mlx5_core_dbg(dev, "requested num_vfs %d\n", num_vfs);
        if (!mlx5_core_is_pf(dev))
                return -EPERM;

        if (num_vfs) {
                int ret;

                ret = mlx5_lag_forbid(dev);
                if (ret && (ret != -ENODEV))
                        return ret;
        }

        if (num_vfs) {
                err = mlx5_sriov_enable(pdev, num_vfs);
        } else {
                mlx5_sriov_disable(pdev);
                mlx5_lag_allow(dev);
        }

        return err ? err : num_vfs;
}

int mlx5_sriov_attach(struct mlx5_core_dev *dev)
{
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;

        if (!mlx5_core_is_pf(dev) || !sriov->num_vfs)
                return 0;

        /* If sriov VFs exist in PCI level, enable them in device level */
        return mlx5_device_enable_sriov(dev, sriov->num_vfs);
}

void mlx5_sriov_detach(struct mlx5_core_dev *dev)
{
        if (!mlx5_core_is_pf(dev))
                return;

        mlx5_device_disable_sriov(dev);
}

int mlx5_sriov_init(struct mlx5_core_dev *dev)
{
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;
        struct pci_dev *pdev = dev->pdev;
        int total_vfs;

        if (!mlx5_core_is_pf(dev))
                return 0;

        total_vfs = pci_sriov_get_totalvfs(pdev);
        sriov->num_vfs = pci_num_vf(pdev);
        sriov->vfs_ctx = kcalloc(total_vfs, sizeof(*sriov->vfs_ctx), GFP_KERNEL);
        if (!sriov->vfs_ctx)
                return -ENOMEM;

        return 0;
}

void mlx5_sriov_cleanup(struct mlx5_core_dev *dev)
{
        struct mlx5_core_sriov *sriov = &dev->priv.sriov;

        if (!mlx5_core_is_pf(dev))
                return;

        kfree(sriov->vfs_ctx);
}