// SPDX-License-Identifier: GPL-2.0-only
/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2018 Solarflare Communications Inc.
 * Copyright 2019-2020 Xilinx Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */
#include "net_driver.h"
#include "mcdi_port_common.h"
#include "mcdi_functions.h"
#include "efx_common.h"
#include "efx_channels.h"
#include "tx_common.h"
#include "ef100_netdev.h"
#include "ef100_ethtool.h"
#include "nic_common.h"
#include "ef100_nic.h"
#include "ef100_tx.h"
#include "ef100_regs.h"
#include "mcdi_filters.h"
#include "rx_common.h"

static void ef100_update_name(struct efx_nic *efx)
{
        strcpy(efx->name, efx->net_dev->name);
}

static int ef100_alloc_vis(struct efx_nic *efx, unsigned int *allocated_vis)
{
        /* EF100 uses a single TXQ per channel, as all checksum offloading
         * is configured in the TX descriptor, and there is no TX Pacer for
         * HIGHPRI queues.
         */
        unsigned int tx_vis = efx->n_tx_channels + efx->n_extra_tx_channels;
        unsigned int rx_vis = efx->n_rx_channels;
        unsigned int min_vis, max_vis;

        EFX_WARN_ON_PARANOID(efx->tx_queues_per_channel != 1);

        tx_vis += efx->n_xdp_channels * efx->xdp_tx_per_channel;

        max_vis = max(rx_vis, tx_vis);
        /* Currently don't handle resource starvation and only accept
         * our maximum needs and no less.
         */
        min_vis = max_vis;

        return efx_mcdi_alloc_vis(efx, min_vis, max_vis,
                                  NULL, allocated_vis);
}

static int ef100_remap_bar(struct efx_nic *efx, int max_vis)
{
        unsigned int uc_mem_map_size;
        void __iomem *membase;

        efx->max_vis = max_vis;
        uc_mem_map_size = PAGE_ALIGN(max_vis * efx->vi_stride);

        /* Extend the original UC mapping of the memory BAR */
        membase = ioremap(efx->membase_phys, uc_mem_map_size);
        if (!membase) {
                netif_err(efx, probe, efx->net_dev,
                          "could not extend memory BAR to %x\n",
                          uc_mem_map_size);
                return -ENOMEM;
        }
        iounmap(efx->membase);
        efx->membase = membase;
        return 0;
}

/* Context: process, rtnl_lock() held.
 * Note that the kernel will ignore our return code; this method
 * should really be a void.
 */
static int ef100_net_stop(struct net_device *net_dev)
{
        struct efx_nic *efx = netdev_priv(net_dev);

        netif_dbg(efx, ifdown, efx->net_dev, "closing on CPU %d\n",
                  raw_smp_processor_id());

        netif_stop_queue(net_dev);
        efx_stop_all(efx);
        efx_mcdi_mac_fini_stats(efx);
        efx_disable_interrupts(efx);
        efx_clear_interrupt_affinity(efx);
        efx_nic_fini_interrupt(efx);
        efx_remove_filters(efx);
        efx_fini_napi(efx);
        efx_remove_channels(efx);
        efx_mcdi_free_vis(efx);
        efx_remove_interrupts(efx);

        return 0;
}

/* Context: process, rtnl_lock() held. */
static int ef100_net_open(struct net_device *net_dev)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        unsigned int allocated_vis;
        int rc;

        ef100_update_name(efx);
        netif_dbg(efx, ifup, net_dev, "opening device on CPU %d\n",
                  raw_smp_processor_id());

        rc = efx_check_disabled(efx);
        if (rc)
                goto fail;

        rc = efx_probe_interrupts(efx);
        if (rc)
                goto fail;

        rc = efx_set_channels(efx);
        if (rc)
                goto fail;

        rc = efx_mcdi_free_vis(efx);
        if (rc)
                goto fail;

        rc = ef100_alloc_vis(efx, &allocated_vis);
        if (rc)
                goto fail;

        rc = efx_probe_channels(efx);
        if (rc)
                return rc;

        rc = ef100_remap_bar(efx, allocated_vis);
        if (rc)
                goto fail;

        efx_init_napi(efx);

        rc = efx_probe_filters(efx);
        if (rc)
                goto fail;

        rc = efx_nic_init_interrupt(efx);
        if (rc)
                goto fail;
        efx_set_interrupt_affinity(efx);

        rc = efx_enable_interrupts(efx);
        if (rc)
                goto fail;

        /* in case the MC rebooted while we were stopped, consume the change
         * to the warm reboot count
         */
        (void) efx_mcdi_poll_reboot(efx);

        rc = efx_mcdi_mac_init_stats(efx);
        if (rc)
                goto fail;

        efx_start_all(efx);

        /* Link state detection is normally event-driven; we have
         * to poll now because we could have missed a change
         */
        mutex_lock(&efx->mac_lock);
        if (efx_mcdi_phy_poll(efx))
                efx_link_status_changed(efx);
        mutex_unlock(&efx->mac_lock);

        return 0;

fail:
        ef100_net_stop(net_dev);
        return rc;
}

/* Initiate a packet transmission.  We use one channel per CPU
 * (sharing when we have more CPUs than channels).
 *
 * Context: non-blocking.
 * Note that returning anything other than NETDEV_TX_OK will cause the
 * OS to free the skb.
 */
static netdev_tx_t ef100_hard_start_xmit(struct sk_buff *skb,
                                         struct net_device *net_dev)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        struct efx_tx_queue *tx_queue;
        struct efx_channel *channel;
        int rc;

        channel = efx_get_tx_channel(efx, skb_get_queue_mapping(skb));
        netif_vdbg(efx, tx_queued, efx->net_dev,
                   "%s len %d data %d channel %d\n", __func__,
                   skb->len, skb->data_len, channel->channel);
        if (!efx->n_channels || !efx->n_tx_channels || !channel) {
                netif_stop_queue(net_dev);
                goto err;
        }

        tx_queue = &channel->tx_queue[0];
        rc = ef100_enqueue_skb(tx_queue, skb);
        if (rc == 0)
                return NETDEV_TX_OK;

err:
        net_dev->stats.tx_dropped++;
        return NETDEV_TX_OK;
}

static const struct net_device_ops ef100_netdev_ops = {
        .ndo_open               = ef100_net_open,
        .ndo_stop               = ef100_net_stop,
        .ndo_start_xmit         = ef100_hard_start_xmit,
        .ndo_tx_timeout         = efx_watchdog,
        .ndo_get_stats64        = efx_net_stats,
        .ndo_change_mtu         = efx_change_mtu,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = efx_set_mac_address,
        .ndo_set_rx_mode        = efx_set_rx_mode, /* Lookout */
        .ndo_set_features       = efx_set_features,
        .ndo_get_phys_port_id   = efx_get_phys_port_id,
        .ndo_get_phys_port_name = efx_get_phys_port_name,
#ifdef CONFIG_RFS_ACCEL
        .ndo_rx_flow_steer      = efx_filter_rfs,
#endif
};

/*      Netdev registration
 */
int ef100_netdev_event(struct notifier_block *this,
                       unsigned long event, void *ptr)
{
        struct efx_nic *efx = container_of(this, struct efx_nic, netdev_notifier);
        struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);

        if (netdev_priv(net_dev) == efx && event == NETDEV_CHANGENAME)
                ef100_update_name(efx);

        return NOTIFY_DONE;
}

int ef100_register_netdev(struct efx_nic *efx)
{
        struct net_device *net_dev = efx->net_dev;
        int rc;

        net_dev->watchdog_timeo = 5 * HZ;
        net_dev->irq = efx->pci_dev->irq;
        net_dev->netdev_ops = &ef100_netdev_ops;
        net_dev->min_mtu = EFX_MIN_MTU;
        net_dev->max_mtu = EFX_MAX_MTU;
        net_dev->ethtool_ops = &ef100_ethtool_ops;

        rtnl_lock();

        rc = dev_alloc_name(net_dev, net_dev->name);
        if (rc < 0)
                goto fail_locked;
        ef100_update_name(efx);

        rc = register_netdevice(net_dev);
        if (rc)
                goto fail_locked;

        /* Always start with carrier off; PHY events will detect the link */
        netif_carrier_off(net_dev);

        efx->state = STATE_READY;
        rtnl_unlock();
        efx_init_mcdi_logging(efx);

        return 0;

fail_locked:
        rtnl_unlock();
        netif_err(efx, drv, efx->net_dev, "could not register net dev\n");
        return rc;
}

void ef100_unregister_netdev(struct efx_nic *efx)
{
        if (efx_dev_registered(efx)) {
                efx_fini_mcdi_logging(efx);
                efx->state = STATE_UNINIT;
                unregister_netdev(efx->net_dev);
        }
}