sfc: Speed up loopback self-test

[linux-2.6/verdex.git] / drivers / net / sfc / selftest.c

/****************************************************************************
 * Driver for Solarflare Solarstorm network controllers and boards
 * Copyright 2005-2006 Fen Systems Ltd.
 * Copyright 2006-2008 Solarflare Communications 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 <linux/netdevice.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/kernel_stat.h>
#include <linux/pci.h>
#include <linux/ethtool.h>
#include <linux/ip.h>
#include <linux/in.h>
#include <linux/udp.h>
#include <linux/rtnetlink.h>
#include <asm/io.h>
#include "net_driver.h"
#include "ethtool.h"
#include "efx.h"
#include "falcon.h"
#include "selftest.h"
#include "boards.h"
#include "workarounds.h"
#include "mac.h"

/*
 * Loopback test packet structure
 *
 * The self-test should stress every RSS vector, and unfortunately
 * Falcon only performs RSS on TCP/UDP packets.
 */
struct efx_loopback_payload {
        struct ethhdr header;
        struct iphdr ip;
        struct udphdr udp;
        __be16 iteration;
        const char msg[64];
} __attribute__ ((packed));

/* Loopback test source MAC address */
static const unsigned char payload_source[ETH_ALEN] = {
        0x00, 0x0f, 0x53, 0x1b, 0x1b, 0x1b,
};

static const char *payload_msg =
        "Hello world! This is an Efx loopback test in progress!";

/**
 * efx_selftest_state - persistent state during a selftest
 * @flush:              Drop all packets in efx_loopback_rx_packet
 * @packet_count:       Number of packets being used in this test
 * @skbs:               An array of skbs transmitted
 * @rx_good:            RX good packet count
 * @rx_bad:             RX bad packet count
 * @payload:            Payload used in tests
 */
struct efx_selftest_state {
        int flush;
        int packet_count;
        struct sk_buff **skbs;

        /* Checksums are being offloaded */
        int offload_csum;

        atomic_t rx_good;
        atomic_t rx_bad;
        struct efx_loopback_payload payload;
};

/**************************************************************************
 *
 * Configurable values
 *
 **************************************************************************/

/* Level of loopback testing
 *
 * The maximum packet burst length is 16**(n-1), i.e.
 *
 * - Level 0 : no packets
 * - Level 1 : 1 packet
 * - Level 2 : 17 packets (1 * 1 packet, 1 * 16 packets)
 * - Level 3 : 273 packets (1 * 1 packet, 1 * 16 packet, 1 * 256 packets)
 *
 */
static unsigned int loopback_test_level = 3;

/**************************************************************************
 *
 * Interrupt and event queue testing
 *
 **************************************************************************/

/* Test generation and receipt of interrupts */
static int efx_test_interrupts(struct efx_nic *efx,
                               struct efx_self_tests *tests)
{
        struct efx_channel *channel;

        EFX_LOG(efx, "testing interrupts\n");
        tests->interrupt = -1;

        /* Reset interrupt flag */
        efx->last_irq_cpu = -1;
        smp_wmb();

        /* ACK each interrupting event queue. Receiving an interrupt due to
         * traffic before a test event is raised is considered a pass */
        efx_for_each_channel_with_interrupt(channel, efx) {
                if (channel->work_pending)
                        efx_process_channel_now(channel);
                if (efx->last_irq_cpu >= 0)
                        goto success;
        }

        falcon_generate_interrupt(efx);

        /* Wait for arrival of test interrupt. */
        EFX_LOG(efx, "waiting for test interrupt\n");
        schedule_timeout_uninterruptible(HZ / 10);
        if (efx->last_irq_cpu >= 0)
                goto success;

        EFX_ERR(efx, "timed out waiting for interrupt\n");
        return -ETIMEDOUT;

 success:
        EFX_LOG(efx, "test interrupt (mode %d) seen on CPU%d\n",
                efx->interrupt_mode, efx->last_irq_cpu);
        tests->interrupt = 1;
        return 0;
}

/* Test generation and receipt of non-interrupting events */
static int efx_test_eventq(struct efx_channel *channel,
                           struct efx_self_tests *tests)
{
        unsigned int magic;

        /* Channel specific code, limited to 20 bits */
        magic = (0x00010150 + channel->channel);
        EFX_LOG(channel->efx, "channel %d testing event queue with code %x\n",
                channel->channel, magic);

        tests->eventq_dma[channel->channel] = -1;
        tests->eventq_int[channel->channel] = 1;        /* fake pass */
        tests->eventq_poll[channel->channel] = 1;       /* fake pass */

        /* Reset flag and zero magic word */
        channel->efx->last_irq_cpu = -1;
        channel->eventq_magic = 0;
        smp_wmb();

        falcon_generate_test_event(channel, magic);
        udelay(1);

        efx_process_channel_now(channel);
        if (channel->eventq_magic != magic) {
                EFX_ERR(channel->efx, "channel %d  failed to see test event\n",
                        channel->channel);
                return -ETIMEDOUT;
        } else {
                tests->eventq_dma[channel->channel] = 1;
        }

        return 0;
}

/* Test generation and receipt of interrupting events */
static int efx_test_eventq_irq(struct efx_channel *channel,
                               struct efx_self_tests *tests)
{
        unsigned int magic, count;

        /* Channel specific code, limited to 20 bits */
        magic = (0x00010150 + channel->channel);
        EFX_LOG(channel->efx, "channel %d testing event queue with code %x\n",
                channel->channel, magic);

        tests->eventq_dma[channel->channel] = -1;
        tests->eventq_int[channel->channel] = -1;
        tests->eventq_poll[channel->channel] = -1;

        /* Reset flag and zero magic word */
        channel->efx->last_irq_cpu = -1;
        channel->eventq_magic = 0;
        smp_wmb();

        falcon_generate_test_event(channel, magic);

        /* Wait for arrival of interrupt */
        count = 0;
        do {
                schedule_timeout_uninterruptible(HZ / 100);

                if (channel->work_pending)
                        efx_process_channel_now(channel);

                if (channel->eventq_magic == magic)
                        goto eventq_ok;
        } while (++count < 2);

        EFX_ERR(channel->efx, "channel %d timed out waiting for event queue\n",
                channel->channel);

        /* See if interrupt arrived */
        if (channel->efx->last_irq_cpu >= 0) {
                EFX_ERR(channel->efx, "channel %d saw interrupt on CPU%d "
                        "during event queue test\n", channel->channel,
                        raw_smp_processor_id());
                tests->eventq_int[channel->channel] = 1;
        }

        /* Check to see if event was received even if interrupt wasn't */
        efx_process_channel_now(channel);
        if (channel->eventq_magic == magic) {
                EFX_ERR(channel->efx, "channel %d event was generated, but "
                        "failed to trigger an interrupt\n", channel->channel);
                tests->eventq_dma[channel->channel] = 1;
        }

        return -ETIMEDOUT;
 eventq_ok:
        EFX_LOG(channel->efx, "channel %d event queue passed\n",
                channel->channel);
        tests->eventq_dma[channel->channel] = 1;
        tests->eventq_int[channel->channel] = 1;
        tests->eventq_poll[channel->channel] = 1;
        return 0;
}

/**************************************************************************
 *
 * PHY testing
 *
 **************************************************************************/

/* Check PHY presence by reading the PHY ID registers */
static int efx_test_phy(struct efx_nic *efx,
                        struct efx_self_tests *tests)
{
        u16 physid1, physid2;
        struct mii_if_info *mii = &efx->mii;
        struct net_device *net_dev = efx->net_dev;

        if (efx->phy_type == PHY_TYPE_NONE)
                return 0;

        EFX_LOG(efx, "testing PHY presence\n");
        tests->phy_ok = -1;

        physid1 = mii->mdio_read(net_dev, mii->phy_id, MII_PHYSID1);
        physid2 = mii->mdio_read(net_dev, mii->phy_id, MII_PHYSID2);

        if ((physid1 != 0x0000) && (physid1 != 0xffff) &&
            (physid2 != 0x0000) && (physid2 != 0xffff)) {
                EFX_LOG(efx, "found MII PHY %d ID 0x%x:%x\n",
                        mii->phy_id, physid1, physid2);
                tests->phy_ok = 1;
                return 0;
        }

        EFX_ERR(efx, "no MII PHY present with ID %d\n", mii->phy_id);
        return -ENODEV;
}

/**************************************************************************
 *
 * Loopback testing
 * NB Only one loopback test can be executing concurrently.
 *
 **************************************************************************/

/* Loopback test RX callback
 * This is called for each received packet during loopback testing.
 */
void efx_loopback_rx_packet(struct efx_nic *efx,
                            const char *buf_ptr, int pkt_len)
{
        struct efx_selftest_state *state = efx->loopback_selftest;
        struct efx_loopback_payload *received;
        struct efx_loopback_payload *payload;

        BUG_ON(!buf_ptr);

        /* If we are just flushing, then drop the packet */
        if ((state == NULL) || state->flush)
                return;

        payload = &state->payload;
        
        received = (struct efx_loopback_payload *) buf_ptr;
        received->ip.saddr = payload->ip.saddr;
        if (state->offload_csum)
                received->ip.check = payload->ip.check;

        /* Check that header exists */
        if (pkt_len < sizeof(received->header)) {
                EFX_ERR(efx, "saw runt RX packet (length %d) in %s loopback "
                        "test\n", pkt_len, LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that the ethernet header exists */
        if (memcmp(&received->header, &payload->header, ETH_HLEN) != 0) {
                EFX_ERR(efx, "saw non-loopback RX packet in %s loopback test\n",
                        LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check packet length */
        if (pkt_len != sizeof(*payload)) {
                EFX_ERR(efx, "saw incorrect RX packet length %d (wanted %d) in "
                        "%s loopback test\n", pkt_len, (int)sizeof(*payload),
                        LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that IP header matches */
        if (memcmp(&received->ip, &payload->ip, sizeof(payload->ip)) != 0) {
                EFX_ERR(efx, "saw corrupted IP header in %s loopback test\n",
                        LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that msg and padding matches */
        if (memcmp(&received->msg, &payload->msg, sizeof(received->msg)) != 0) {
                EFX_ERR(efx, "saw corrupted RX packet in %s loopback test\n",
                        LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that iteration matches */
        if (received->iteration != payload->iteration) {
                EFX_ERR(efx, "saw RX packet from iteration %d (wanted %d) in "
                        "%s loopback test\n", ntohs(received->iteration),
                        ntohs(payload->iteration), LOOPBACK_MODE(efx));
                goto err;
        }

        /* Increase correct RX count */
        EFX_TRACE(efx, "got loopback RX in %s loopback test\n",
                  LOOPBACK_MODE(efx));

        atomic_inc(&state->rx_good);
        return;

 err:
#ifdef EFX_ENABLE_DEBUG
        if (atomic_read(&state->rx_bad) == 0) {
                EFX_ERR(efx, "received packet:\n");
                print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
                               buf_ptr, pkt_len, 0);
                EFX_ERR(efx, "expected packet:\n");
                print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
                               &state->payload, sizeof(state->payload), 0);
        }
#endif
        atomic_inc(&state->rx_bad);
}

/* Initialise an efx_selftest_state for a new iteration */
static void efx_iterate_state(struct efx_nic *efx)
{
        struct efx_selftest_state *state = efx->loopback_selftest;
        struct net_device *net_dev = efx->net_dev;
        struct efx_loopback_payload *payload = &state->payload;

        /* Initialise the layerII header */
        memcpy(&payload->header.h_dest, net_dev->dev_addr, ETH_ALEN);
        memcpy(&payload->header.h_source, &payload_source, ETH_ALEN);
        payload->header.h_proto = htons(ETH_P_IP);

        /* saddr set later and used as incrementing count */
        payload->ip.daddr = htonl(INADDR_LOOPBACK);
        payload->ip.ihl = 5;
        payload->ip.check = htons(0xdead);
        payload->ip.tot_len = htons(sizeof(*payload) - sizeof(struct ethhdr));
        payload->ip.version = IPVERSION;
        payload->ip.protocol = IPPROTO_UDP;

        /* Initialise udp header */
        payload->udp.source = 0;
        payload->udp.len = htons(sizeof(*payload) - sizeof(struct ethhdr) -
                                 sizeof(struct iphdr));
        payload->udp.check = 0; /* checksum ignored */

        /* Fill out payload */
        payload->iteration = htons(ntohs(payload->iteration) + 1);
        memcpy(&payload->msg, payload_msg, sizeof(payload_msg));

        /* Fill out remaining state members */
        atomic_set(&state->rx_good, 0);
        atomic_set(&state->rx_bad, 0);
        smp_wmb();
}

static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
{
        struct efx_nic *efx = tx_queue->efx;
        struct efx_selftest_state *state = efx->loopback_selftest;
        struct efx_loopback_payload *payload;
        struct sk_buff *skb;
        int i, rc;

        /* Transmit N copies of buffer */
        for (i = 0; i < state->packet_count; i++) {
                /* Allocate an skb, holding an extra reference for 
                 * transmit completion counting */
                skb = alloc_skb(sizeof(state->payload), GFP_KERNEL);
                if (!skb)
                        return -ENOMEM;
                state->skbs[i] = skb;
                skb_get(skb);

                /* Copy the payload in, incrementing the source address to
                 * exercise the rss vectors */
                payload = ((struct efx_loopback_payload *)
                           skb_put(skb, sizeof(state->payload)));
                memcpy(payload, &state->payload, sizeof(state->payload));
                payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));

                /* Ensure everything we've written is visible to the
                 * interrupt handler. */
                smp_wmb();

                if (efx_dev_registered(efx))
                        netif_tx_lock_bh(efx->net_dev);
                rc = efx_xmit(efx, tx_queue, skb);
                if (efx_dev_registered(efx))
                        netif_tx_unlock_bh(efx->net_dev);

                if (rc != NETDEV_TX_OK) {
                        EFX_ERR(efx, "TX queue %d could not transmit packet %d "
                                "of %d in %s loopback test\n", tx_queue->queue,
                                i + 1, state->packet_count, LOOPBACK_MODE(efx));

                        /* Defer cleaning up the other skbs for the caller */
                        kfree_skb(skb);
                        return -EPIPE;
                }
        }

        return 0;
}

static int efx_poll_loopback(struct efx_nic *efx)
{
        struct efx_selftest_state *state = efx->loopback_selftest;
        struct efx_channel *channel;

        /* NAPI polling is not enabled, so process channels
         * synchronously */
        efx_for_each_channel_with_interrupt(channel, efx) {
                if (channel->work_pending)
                        efx_process_channel_now(channel);
        }
        return atomic_read(&state->rx_good) == state->packet_count;
}

static int efx_end_loopback(struct efx_tx_queue *tx_queue,
                            struct efx_loopback_self_tests *lb_tests)
{
        struct efx_nic *efx = tx_queue->efx;
        struct efx_selftest_state *state = efx->loopback_selftest;
        struct sk_buff *skb;
        int tx_done = 0, rx_good, rx_bad;
        int i, rc = 0;

        if (efx_dev_registered(efx))
                netif_tx_lock_bh(efx->net_dev);

        /* Count the number of tx completions, and decrement the refcnt. Any
         * skbs not already completed will be free'd when the queue is flushed */
        for (i=0; i < state->packet_count; i++) {
                skb = state->skbs[i];
                if (skb && !skb_shared(skb))
                        ++tx_done;
                dev_kfree_skb_any(skb);
        }

        if (efx_dev_registered(efx))
                netif_tx_unlock_bh(efx->net_dev);

        /* Check TX completion and received packet counts */
        rx_good = atomic_read(&state->rx_good);
        rx_bad = atomic_read(&state->rx_bad);
        if (tx_done != state->packet_count) {
                /* Don't free the skbs; they will be picked up on TX
                 * overflow or channel teardown.
                 */
                EFX_ERR(efx, "TX queue %d saw only %d out of an expected %d "
                        "TX completion events in %s loopback test\n",
                        tx_queue->queue, tx_done, state->packet_count,
                        LOOPBACK_MODE(efx));
                rc = -ETIMEDOUT;
                /* Allow to fall through so we see the RX errors as well */
        }

        /* We may always be up to a flush away from our desired packet total */
        if (rx_good != state->packet_count) {
                EFX_LOG(efx, "TX queue %d saw only %d out of an expected %d "
                        "received packets in %s loopback test\n",
                        tx_queue->queue, rx_good, state->packet_count,
                        LOOPBACK_MODE(efx));
                rc = -ETIMEDOUT;
                /* Fall through */
        }

        /* Update loopback test structure */
        lb_tests->tx_sent[tx_queue->queue] += state->packet_count;
        lb_tests->tx_done[tx_queue->queue] += tx_done;
        lb_tests->rx_good += rx_good;
        lb_tests->rx_bad += rx_bad;

        return rc;
}

static int
efx_test_loopback(struct efx_tx_queue *tx_queue,
                  struct efx_loopback_self_tests *lb_tests)
{
        struct efx_nic *efx = tx_queue->efx;
        struct efx_selftest_state *state = efx->loopback_selftest;
        int i, begin_rc, end_rc;

        for (i = 0; i < loopback_test_level; i++) {
                /* Determine how many packets to send */
                state->packet_count = (efx->type->txd_ring_mask + 1) / 3;
                state->packet_count = min(1 << (i << 2), state->packet_count);
                state->skbs = kzalloc(sizeof(state->skbs[0]) *
                                      state->packet_count, GFP_KERNEL);
                if (!state->skbs)
                        return -ENOMEM;
                state->flush = 0;

                EFX_LOG(efx, "TX queue %d testing %s loopback with %d "
                        "packets\n", tx_queue->queue, LOOPBACK_MODE(efx),
                        state->packet_count);

                efx_iterate_state(efx);
                begin_rc = efx_begin_loopback(tx_queue);

                /* This will normally complete very quickly, but be
                 * prepared to wait up to 100 ms. */
                msleep(1);
                if (!efx_poll_loopback(efx)) {
                        msleep(100);
                        efx_poll_loopback(efx);
                }

                end_rc = efx_end_loopback(tx_queue, lb_tests);
                kfree(state->skbs);

                if (begin_rc || end_rc) {
                        /* Wait a while to ensure there are no packets
                         * floating around after a failure. */
                        schedule_timeout_uninterruptible(HZ / 10);
                        return begin_rc ? begin_rc : end_rc;
                }
        }

        EFX_LOG(efx, "TX queue %d passed %s loopback test with a burst length "
                "of %d packets\n", tx_queue->queue, LOOPBACK_MODE(efx),
                state->packet_count);

        return 0;
}

static int efx_test_loopbacks(struct efx_nic *efx,
                              struct efx_self_tests *tests,
                              unsigned int loopback_modes)
{
        struct efx_selftest_state *state = efx->loopback_selftest;
        struct ethtool_cmd ecmd, ecmd_loopback;
        struct efx_tx_queue *tx_queue;
        enum efx_loopback_mode old_mode, mode;
        int count, rc, link_up;

        rc = efx_ethtool_get_settings(efx->net_dev, &ecmd);
        if (rc) {
                EFX_ERR(efx, "could not get GMII settings\n");
                return rc;
        }
        old_mode = efx->loopback_mode;

        /* Disable autonegotiation for the purposes of loopback */
        memcpy(&ecmd_loopback, &ecmd, sizeof(ecmd_loopback));
        if (ecmd_loopback.autoneg == AUTONEG_ENABLE) {
                ecmd_loopback.autoneg = AUTONEG_DISABLE;
                ecmd_loopback.duplex = DUPLEX_FULL;
                ecmd_loopback.speed = SPEED_10000;
        }

        rc = efx_ethtool_set_settings(efx->net_dev, &ecmd_loopback);
        if (rc) {
                EFX_ERR(efx, "could not disable autonegotiation\n");
                goto out;
        }
        tests->loopback_speed = ecmd_loopback.speed;
        tests->loopback_full_duplex = ecmd_loopback.duplex;

        /* Test all supported loopback modes */
        for (mode = LOOPBACK_NONE; mode < LOOPBACK_TEST_MAX; mode++) {
                if (!(loopback_modes & (1 << mode)))
                        continue;

                /* Move the port into the specified loopback mode. */
                state->flush = 1;
                efx->loopback_mode = mode;
                efx_reconfigure_port(efx);

                /* Wait for the PHY to signal the link is up */
                count = 0;
                do {
                        struct efx_channel *channel = &efx->channel[0];

                        falcon_check_xmac(efx);
                        schedule_timeout_uninterruptible(HZ / 10);
                        if (channel->work_pending)
                                efx_process_channel_now(channel);
                        /* Wait for PHY events to be processed */
                        flush_workqueue(efx->workqueue);
                        rmb();

                        /* efx->link_up can be 1 even if the XAUI link is down,
                         * (bug5762). Usually, it's not worth bothering with the
                         * difference, but for selftests, we need that extra
                         * guarantee that the link is really, really, up.
                         */
                        link_up = efx->link_up;
                        if (!falcon_xaui_link_ok(efx))
                                link_up = 0;

                } while ((++count < 20) && !link_up);

                /* The link should now be up. If it isn't, there is no point
                 * in attempting a loopback test */
                if (!link_up) {
                        EFX_ERR(efx, "loopback %s never came up\n",
                                LOOPBACK_MODE(efx));
                        rc = -EIO;
                        goto out;
                }

                EFX_LOG(efx, "link came up in %s loopback in %d iterations\n",
                        LOOPBACK_MODE(efx), count);

                /* Test every TX queue */
                efx_for_each_tx_queue(tx_queue, efx) {
                        state->offload_csum = (tx_queue->queue ==
                                               EFX_TX_QUEUE_OFFLOAD_CSUM);
                        rc = efx_test_loopback(tx_queue,
                                               &tests->loopback[mode]);
                        if (rc)
                                goto out;
                }
        }

 out:
        /* Take out of loopback and restore PHY settings */
        state->flush = 1;
        efx->loopback_mode = old_mode;
        efx_ethtool_set_settings(efx->net_dev, &ecmd);

        return rc;
}

/**************************************************************************
 *
 * Entry points
 *
 *************************************************************************/

/* Online (i.e. non-disruptive) testing
 * This checks interrupt generation, event delivery and PHY presence. */
int efx_online_test(struct efx_nic *efx, struct efx_self_tests *tests)
{
        struct efx_channel *channel;
        int rc;

        rc = efx_test_interrupts(efx, tests);
        if (rc)
                return rc;
        efx_for_each_channel(channel, efx) {
                if (channel->has_interrupt)
                        rc = efx_test_eventq_irq(channel, tests);
                else
                        rc = efx_test_eventq(channel, tests);
                if (rc)
                        return rc;
        }
        rc = efx_test_phy(efx, tests);
        return rc;
}

/* Offline (i.e. disruptive) testing
 * This checks MAC and PHY loopback on the specified port. */
int efx_offline_test(struct efx_nic *efx,
                     struct efx_self_tests *tests, unsigned int loopback_modes)
{
        struct efx_selftest_state *state;
        int rc;

        /* Create a selftest_state structure to hold state for the test */
        state = kzalloc(sizeof(*state), GFP_KERNEL);
        if (state == NULL)
                return -ENOMEM;

        /* Set the port loopback_selftest member. From this point on
         * all received packets will be dropped. Mark the state as
         * "flushing" so all inflight packets are dropped */
        BUG_ON(efx->loopback_selftest);
        state->flush = 1;
        efx->loopback_selftest = state;

        rc = efx_test_loopbacks(efx, tests, loopback_modes);

        efx->loopback_selftest = NULL;
        wmb();
        kfree(state);

        return rc;
}