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OpenCloudOS-Kernel/drivers/net/ethernet/sfc/selftest.c

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/****************************************************************************
* Driver for Solarflare network controllers and boards
* Copyright 2005-2006 Fen Systems Ltd.
* Copyright 2006-2012 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 <linux/slab.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"
#include "selftest.h"
#include "workarounds.h"
/* IRQ latency can be enormous because:
* - All IRQs may be disabled on a CPU for a *long* time by e.g. a
* slow serial console or an old IDE driver doing error recovery
* - The PREEMPT_RT patches mostly deal with this, but also allow a
* tasklet or normal task to be given higher priority than our IRQ
* threads
* Try to avoid blaming the hardware for this.
*/
#define IRQ_TIMEOUT HZ
/*
* 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];
} __packed;
/* Loopback test source MAC address */
static const u8 payload_source[ETH_ALEN] __aligned(2) = {
0x00, 0x0f, 0x53, 0x1b, 0x1b, 0x1b,
};
static const char payload_msg[] =
"Hello world! This is an Efx loopback test in progress!";
/* Interrupt mode names */
static const unsigned int efx_interrupt_mode_max = EFX_INT_MODE_MAX;
static const char *const efx_interrupt_mode_names[] = {
[EFX_INT_MODE_MSIX] = "MSI-X",
[EFX_INT_MODE_MSI] = "MSI",
[EFX_INT_MODE_LEGACY] = "legacy",
};
#define INT_MODE(efx) \
STRING_TABLE_LOOKUP(efx->interrupt_mode, efx_interrupt_mode)
/**
* efx_loopback_state - persistent state during a loopback 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
* @offload_csum: Checksums are being offloaded
* @rx_good: RX good packet count
* @rx_bad: RX bad packet count
* @payload: Payload used in tests
*/
struct efx_loopback_state {
bool flush;
int packet_count;
struct sk_buff **skbs;
bool offload_csum;
atomic_t rx_good;
atomic_t rx_bad;
struct efx_loopback_payload payload;
};
/* How long to wait for all the packets to arrive (in ms) */
#define LOOPBACK_TIMEOUT_MS 1000
/**************************************************************************
*
* MII, NVRAM and register tests
*
**************************************************************************/
static int efx_test_phy_alive(struct efx_nic *efx, struct efx_self_tests *tests)
{
int rc = 0;
if (efx->phy_op->test_alive) {
rc = efx->phy_op->test_alive(efx);
tests->phy_alive = rc ? -1 : 1;
}
return rc;
}
static int efx_test_nvram(struct efx_nic *efx, struct efx_self_tests *tests)
{
int rc = 0;
if (efx->type->test_nvram) {
rc = efx->type->test_nvram(efx);
tests->nvram = rc ? -1 : 1;
}
return rc;
}
/**************************************************************************
*
* 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)
{
unsigned long timeout, wait;
int cpu;
netif_dbg(efx, drv, efx->net_dev, "testing interrupts\n");
tests->interrupt = -1;
efx_nic_irq_test_start(efx);
timeout = jiffies + IRQ_TIMEOUT;
wait = 1;
/* Wait for arrival of test interrupt. */
netif_dbg(efx, drv, efx->net_dev, "waiting for test interrupt\n");
do {
schedule_timeout_uninterruptible(wait);
cpu = efx_nic_irq_test_irq_cpu(efx);
if (cpu >= 0)
goto success;
wait *= 2;
} while (time_before(jiffies, timeout));
netif_err(efx, drv, efx->net_dev, "timed out waiting for interrupt\n");
return -ETIMEDOUT;
success:
netif_dbg(efx, drv, efx->net_dev, "%s test interrupt seen on CPU%d\n",
INT_MODE(efx), cpu);
tests->interrupt = 1;
return 0;
}
/* Test generation and receipt of interrupting events */
static int efx_test_eventq_irq(struct efx_nic *efx,
struct efx_self_tests *tests)
{
struct efx_channel *channel;
unsigned int read_ptr[EFX_MAX_CHANNELS];
unsigned long napi_ran = 0, dma_pend = 0, int_pend = 0;
unsigned long timeout, wait;
BUILD_BUG_ON(EFX_MAX_CHANNELS > BITS_PER_LONG);
efx_for_each_channel(channel, efx) {
read_ptr[channel->channel] = channel->eventq_read_ptr;
set_bit(channel->channel, &dma_pend);
set_bit(channel->channel, &int_pend);
efx_nic_event_test_start(channel);
}
timeout = jiffies + IRQ_TIMEOUT;
wait = 1;
/* Wait for arrival of interrupts. NAPI processing may or may
* not complete in time, but we can cope in any case.
*/
do {
schedule_timeout_uninterruptible(wait);
efx_for_each_channel(channel, efx) {
efx_stop_eventq(channel);
if (channel->eventq_read_ptr !=
read_ptr[channel->channel]) {
set_bit(channel->channel, &napi_ran);
clear_bit(channel->channel, &dma_pend);
clear_bit(channel->channel, &int_pend);
} else {
if (efx_nic_event_present(channel))
clear_bit(channel->channel, &dma_pend);
if (efx_nic_event_test_irq_cpu(channel) >= 0)
clear_bit(channel->channel, &int_pend);
}
efx_start_eventq(channel);
}
wait *= 2;
} while ((dma_pend || int_pend) && time_before(jiffies, timeout));
efx_for_each_channel(channel, efx) {
bool dma_seen = !test_bit(channel->channel, &dma_pend);
bool int_seen = !test_bit(channel->channel, &int_pend);
tests->eventq_dma[channel->channel] = dma_seen ? 1 : -1;
tests->eventq_int[channel->channel] = int_seen ? 1 : -1;
if (dma_seen && int_seen) {
netif_dbg(efx, drv, efx->net_dev,
"channel %d event queue passed (with%s NAPI)\n",
channel->channel,
test_bit(channel->channel, &napi_ran) ?
"" : "out");
} else {
/* Report failure and whether either interrupt or DMA
* worked
*/
netif_err(efx, drv, efx->net_dev,
"channel %d timed out waiting for event queue\n",
channel->channel);
if (int_seen)
netif_err(efx, drv, efx->net_dev,
"channel %d saw interrupt "
"during event queue test\n",
channel->channel);
if (dma_seen)
netif_err(efx, drv, efx->net_dev,
"channel %d event was generated, but "
"failed to trigger an interrupt\n",
channel->channel);
}
}
return (dma_pend || int_pend) ? -ETIMEDOUT : 0;
}
static int efx_test_phy(struct efx_nic *efx, struct efx_self_tests *tests,
unsigned flags)
{
int rc;
if (!efx->phy_op->run_tests)
return 0;
mutex_lock(&efx->mac_lock);
rc = efx->phy_op->run_tests(efx, tests->phy_ext, flags);
mutex_unlock(&efx->mac_lock);
return rc;
}
/**************************************************************************
*
* 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_loopback_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)) {
netif_err(efx, drv, efx->net_dev,
"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) {
netif_err(efx, drv, efx->net_dev,
"saw non-loopback RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
goto err;
}
/* Check packet length */
if (pkt_len != sizeof(*payload)) {
netif_err(efx, drv, efx->net_dev,
"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) {
netif_err(efx, drv, efx->net_dev,
"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) {
netif_err(efx, drv, efx->net_dev,
"saw corrupted RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
goto err;
}
/* Check that iteration matches */
if (received->iteration != payload->iteration) {
netif_err(efx, drv, efx->net_dev,
"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 */
netif_vdbg(efx, drv, efx->net_dev,
"got loopback RX in %s loopback test\n", LOOPBACK_MODE(efx));
atomic_inc(&state->rx_good);
return;
err:
#ifdef DEBUG
if (atomic_read(&state->rx_bad) == 0) {
netif_err(efx, drv, efx->net_dev, "received packet:\n");
print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
buf_ptr, pkt_len, 0);
netif_err(efx, drv, efx->net_dev, "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_loopback_state *state = efx->loopback_selftest;
struct net_device *net_dev = efx->net_dev;
struct efx_loopback_payload *payload = &state->payload;
/* Initialise the layerII header */
ether_addr_copy((u8 *)&payload->header.h_dest, net_dev->dev_addr);
ether_addr_copy((u8 *)&payload->header.h_source, payload_source);
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 = (__force __sum16) 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_loopback_state *state = efx->loopback_selftest;
struct efx_loopback_payload *payload;
struct sk_buff *skb;
int i;
netdev_tx_t 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();
netif_tx_lock_bh(efx->net_dev);
rc = efx_enqueue_skb(tx_queue, skb);
netif_tx_unlock_bh(efx->net_dev);
if (rc != NETDEV_TX_OK) {
netif_err(efx, drv, efx->net_dev,
"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_loopback_state *state = efx->loopback_selftest;
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_loopback_state *state = efx->loopback_selftest;
struct sk_buff *skb;
int tx_done = 0, rx_good, rx_bad;
int i, rc = 0;
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(skb);
}
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.
*/
netif_err(efx, drv, efx->net_dev,
"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) {
netif_dbg(efx, drv, efx->net_dev,
"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_loopback_state *state = efx->loopback_selftest;
int i, begin_rc, end_rc;
for (i = 0; i < 3; i++) {
/* Determine how many packets to send */
state->packet_count = efx->txq_entries / 3;
state->packet_count = min(1 << (i << 2), state->packet_count);
state->skbs = kcalloc(state->packet_count,
sizeof(state->skbs[0]), GFP_KERNEL);
if (!state->skbs)
return -ENOMEM;
state->flush = false;
netif_dbg(efx, drv, efx->net_dev,
"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 much longer. */
msleep(1);
if (!efx_poll_loopback(efx)) {
msleep(LOOPBACK_TIMEOUT_MS);
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;
}
}
netif_dbg(efx, drv, efx->net_dev,
"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;
}
/* Wait for link up. On Falcon, we would prefer to rely on efx_monitor, but
* any contention on the mac lock (via e.g. efx_mac_mcast_work) causes it
* to delay and retry. Therefore, it's safer to just poll directly. Wait
* for link up and any faults to dissipate. */
static int efx_wait_for_link(struct efx_nic *efx)
{
struct efx_link_state *link_state = &efx->link_state;
int count, link_up_count = 0;
bool link_up;
for (count = 0; count < 40; count++) {
schedule_timeout_uninterruptible(HZ / 10);
if (efx->type->monitor != NULL) {
mutex_lock(&efx->mac_lock);
efx->type->monitor(efx);
mutex_unlock(&efx->mac_lock);
}
mutex_lock(&efx->mac_lock);
link_up = link_state->up;
if (link_up)
link_up = !efx->type->check_mac_fault(efx);
mutex_unlock(&efx->mac_lock);
if (link_up) {
if (++link_up_count == 2)
return 0;
} else {
link_up_count = 0;
}
}
return -ETIMEDOUT;
}
static int efx_test_loopbacks(struct efx_nic *efx, struct efx_self_tests *tests,
unsigned int loopback_modes)
{
enum efx_loopback_mode mode;
struct efx_loopback_state *state;
struct efx_channel *channel =
efx_get_channel(efx, efx->tx_channel_offset);
struct efx_tx_queue *tx_queue;
int rc = 0;
/* 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 */
state = kzalloc(sizeof(*state), GFP_KERNEL);
if (state == NULL)
return -ENOMEM;
BUG_ON(efx->loopback_selftest);
state->flush = true;
efx->loopback_selftest = state;
/* 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 = true;
mutex_lock(&efx->mac_lock);
efx->loopback_mode = mode;
rc = __efx_reconfigure_port(efx);
mutex_unlock(&efx->mac_lock);
if (rc) {
netif_err(efx, drv, efx->net_dev,
"unable to move into %s loopback\n",
LOOPBACK_MODE(efx));
goto out;
}
rc = efx_wait_for_link(efx);
if (rc) {
netif_err(efx, drv, efx->net_dev,
"loopback %s never came up\n",
LOOPBACK_MODE(efx));
goto out;
}
/* Test all enabled types of TX queue */
efx_for_each_channel_tx_queue(tx_queue, channel) {
state->offload_csum = (tx_queue->queue &
EFX_TXQ_TYPE_OFFLOAD);
rc = efx_test_loopback(tx_queue,
&tests->loopback[mode]);
if (rc)
goto out;
}
}
out:
/* Remove the flush. The caller will remove the loopback setting */
state->flush = true;
efx->loopback_selftest = NULL;
wmb();
kfree(state);
return rc;
}
/**************************************************************************
*
* Entry point
*
*************************************************************************/
int efx_selftest(struct efx_nic *efx, struct efx_self_tests *tests,
unsigned flags)
{
enum efx_loopback_mode loopback_mode = efx->loopback_mode;
int phy_mode = efx->phy_mode;
int rc_test = 0, rc_reset, rc;
efx_selftest_async_cancel(efx);
/* Online (i.e. non-disruptive) testing
* This checks interrupt generation, event delivery and PHY presence. */
rc = efx_test_phy_alive(efx, tests);
if (rc && !rc_test)
rc_test = rc;
rc = efx_test_nvram(efx, tests);
if (rc && !rc_test)
rc_test = rc;
rc = efx_test_interrupts(efx, tests);
if (rc && !rc_test)
rc_test = rc;
rc = efx_test_eventq_irq(efx, tests);
if (rc && !rc_test)
rc_test = rc;
if (rc_test)
return rc_test;
if (!(flags & ETH_TEST_FL_OFFLINE))
return efx_test_phy(efx, tests, flags);
/* Offline (i.e. disruptive) testing
* This checks MAC and PHY loopback on the specified port. */
/* Detach the device so the kernel doesn't transmit during the
* loopback test and the watchdog timeout doesn't fire.
*/
efx_device_detach_sync(efx);
if (efx->type->test_chip) {
rc_reset = efx->type->test_chip(efx, tests);
if (rc_reset) {
netif_err(efx, hw, efx->net_dev,
"Unable to recover from chip test\n");
efx_schedule_reset(efx, RESET_TYPE_DISABLE);
return rc_reset;
}
if ((tests->memory < 0 || tests->registers < 0) && !rc_test)
rc_test = -EIO;
}
/* Ensure that the phy is powered and out of loopback
* for the bist and loopback tests */
mutex_lock(&efx->mac_lock);
efx->phy_mode &= ~PHY_MODE_LOW_POWER;
efx->loopback_mode = LOOPBACK_NONE;
__efx_reconfigure_port(efx);
mutex_unlock(&efx->mac_lock);
rc = efx_test_phy(efx, tests, flags);
if (rc && !rc_test)
rc_test = rc;
rc = efx_test_loopbacks(efx, tests, efx->loopback_modes);
if (rc && !rc_test)
rc_test = rc;
/* restore the PHY to the previous state */
mutex_lock(&efx->mac_lock);
efx->phy_mode = phy_mode;
efx->loopback_mode = loopback_mode;
__efx_reconfigure_port(efx);
mutex_unlock(&efx->mac_lock);
netif_device_attach(efx->net_dev);
return rc_test;
}
void efx_selftest_async_start(struct efx_nic *efx)
{
struct efx_channel *channel;
efx_for_each_channel(channel, efx)
efx_nic_event_test_start(channel);
schedule_delayed_work(&efx->selftest_work, IRQ_TIMEOUT);
}
void efx_selftest_async_cancel(struct efx_nic *efx)
{
cancel_delayed_work_sync(&efx->selftest_work);
}
void efx_selftest_async_work(struct work_struct *data)
{
struct efx_nic *efx = container_of(data, struct efx_nic,
selftest_work.work);
struct efx_channel *channel;
int cpu;
efx_for_each_channel(channel, efx) {
cpu = efx_nic_event_test_irq_cpu(channel);
if (cpu < 0)
netif_err(efx, ifup, efx->net_dev,
"channel %d failed to trigger an interrupt\n",
channel->channel);
else
netif_dbg(efx, ifup, efx->net_dev,
"channel %d triggered interrupt on CPU %d\n",
channel->channel, cpu);
}
}
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