linux/drivers/net/ethernet/sfc/nic_common.h

287 lines
9.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/****************************************************************************
* Driver for Solarflare network controllers and boards
* Copyright 2005-2006 Fen Systems Ltd.
* Copyright 2006-2013 Solarflare Communications Inc.
* Copyright 2019-2020 Xilinx Inc.
*/
#ifndef EFX_NIC_COMMON_H
#define EFX_NIC_COMMON_H
#include "net_driver.h"
#include "efx_common.h"
#include "mcdi.h"
#include "ptp.h"
enum {
/* Revisions 0-2 were Falcon A0, A1 and B0 respectively.
* They are not supported by this driver but these revision numbers
* form part of the ethtool API for register dumping.
*/
EFX_REV_SIENA_A0 = 3,
EFX_REV_HUNT_A0 = 4,
EFX_REV_EF100 = 5,
};
static inline int efx_nic_rev(struct efx_nic *efx)
{
return efx->type->revision;
}
/* Read the current event from the event queue */
static inline efx_qword_t *efx_event(struct efx_channel *channel,
unsigned int index)
{
return ((efx_qword_t *) (channel->eventq.buf.addr)) +
(index & channel->eventq_mask);
}
/* See if an event is present
*
* We check both the high and low dword of the event for all ones. We
* wrote all ones when we cleared the event, and no valid event can
* have all ones in either its high or low dwords. This approach is
* robust against reordering.
*
* Note that using a single 64-bit comparison is incorrect; even
* though the CPU read will be atomic, the DMA write may not be.
*/
static inline int efx_event_present(efx_qword_t *event)
{
return !(EFX_DWORD_IS_ALL_ONES(event->dword[0]) |
EFX_DWORD_IS_ALL_ONES(event->dword[1]));
}
/* Returns a pointer to the specified transmit descriptor in the TX
* descriptor queue belonging to the specified channel.
*/
static inline efx_qword_t *
efx_tx_desc(struct efx_tx_queue *tx_queue, unsigned int index)
{
return ((efx_qword_t *) (tx_queue->txd.buf.addr)) + index;
}
/* Report whether this TX queue would be empty for the given write_count.
* May return false negative.
*/
static inline bool __efx_nic_tx_is_empty(struct efx_tx_queue *tx_queue,
unsigned int write_count)
{
unsigned int empty_read_count = READ_ONCE(tx_queue->empty_read_count);
if (empty_read_count == 0)
return false;
return ((empty_read_count ^ write_count) & ~EFX_EMPTY_COUNT_VALID) == 0;
}
/* Report whether the NIC considers this TX queue empty, using
* packet_write_count (the write count recorded for the last completable
* doorbell push). May return false negative. EF10 only, which is OK
* because only EF10 supports PIO.
*/
static inline bool efx_nic_tx_is_empty(struct efx_tx_queue *tx_queue)
{
EFX_WARN_ON_ONCE_PARANOID(!tx_queue->efx->type->option_descriptors);
return __efx_nic_tx_is_empty(tx_queue, tx_queue->packet_write_count);
}
/* Get partner of a TX queue, seen as part of the same net core queue */
/* XXX is this a thing on EF100? */
static inline struct efx_tx_queue *efx_tx_queue_partner(struct efx_tx_queue *tx_queue)
{
if (tx_queue->label & EFX_TXQ_TYPE_OFFLOAD)
return tx_queue - EFX_TXQ_TYPE_OFFLOAD;
else
return tx_queue + EFX_TXQ_TYPE_OFFLOAD;
}
/* Decide whether we can use TX PIO, ie. write packet data directly into
* a buffer on the device. This can reduce latency at the expense of
* throughput, so we only do this if both hardware and software TX rings
* are empty. This also ensures that only one packet at a time can be
* using the PIO buffer.
*/
static inline bool efx_nic_may_tx_pio(struct efx_tx_queue *tx_queue)
{
struct efx_tx_queue *partner = efx_tx_queue_partner(tx_queue);
return tx_queue->piobuf && efx_nic_tx_is_empty(tx_queue) &&
efx_nic_tx_is_empty(partner);
}
int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue, struct sk_buff *skb,
bool *data_mapped);
/* Decide whether to push a TX descriptor to the NIC vs merely writing
* the doorbell. This can reduce latency when we are adding a single
* descriptor to an empty queue, but is otherwise pointless. Further,
* Falcon and Siena have hardware bugs (SF bug 33851) that may be
* triggered if we don't check this.
* We use the write_count used for the last doorbell push, to get the
* NIC's view of the tx queue.
*/
static inline bool efx_nic_may_push_tx_desc(struct efx_tx_queue *tx_queue,
unsigned int write_count)
{
bool was_empty = __efx_nic_tx_is_empty(tx_queue, write_count);
tx_queue->empty_read_count = 0;
return was_empty && tx_queue->write_count - write_count == 1;
}
/* Returns a pointer to the specified descriptor in the RX descriptor queue */
static inline efx_qword_t *
efx_rx_desc(struct efx_rx_queue *rx_queue, unsigned int index)
{
return ((efx_qword_t *) (rx_queue->rxd.buf.addr)) + index;
}
/* Alignment of PCIe DMA boundaries (4KB) */
#define EFX_PAGE_SIZE 4096
/* Size and alignment of buffer table entries (same) */
#define EFX_BUF_SIZE EFX_PAGE_SIZE
/* NIC-generic software stats */
enum {
GENERIC_STAT_rx_noskb_drops,
GENERIC_STAT_rx_nodesc_trunc,
GENERIC_STAT_COUNT
};
#define EFX_GENERIC_SW_STAT(ext_name) \
[GENERIC_STAT_ ## ext_name] = { #ext_name, 0, 0 }
/* TX data path */
static inline int efx_nic_probe_tx(struct efx_tx_queue *tx_queue)
{
return tx_queue->efx->type->tx_probe(tx_queue);
}
static inline void efx_nic_init_tx(struct efx_tx_queue *tx_queue)
{
tx_queue->efx->type->tx_init(tx_queue);
}
static inline void efx_nic_remove_tx(struct efx_tx_queue *tx_queue)
{
if (tx_queue->efx->type->tx_remove)
tx_queue->efx->type->tx_remove(tx_queue);
}
static inline void efx_nic_push_buffers(struct efx_tx_queue *tx_queue)
{
tx_queue->efx->type->tx_write(tx_queue);
}
/* RX data path */
static inline int efx_nic_probe_rx(struct efx_rx_queue *rx_queue)
{
return rx_queue->efx->type->rx_probe(rx_queue);
}
static inline void efx_nic_init_rx(struct efx_rx_queue *rx_queue)
{
rx_queue->efx->type->rx_init(rx_queue);
}
static inline void efx_nic_remove_rx(struct efx_rx_queue *rx_queue)
{
rx_queue->efx->type->rx_remove(rx_queue);
}
static inline void efx_nic_notify_rx_desc(struct efx_rx_queue *rx_queue)
{
rx_queue->efx->type->rx_write(rx_queue);
}
static inline void efx_nic_generate_fill_event(struct efx_rx_queue *rx_queue)
{
rx_queue->efx->type->rx_defer_refill(rx_queue);
}
/* Event data path */
static inline int efx_nic_probe_eventq(struct efx_channel *channel)
{
return channel->efx->type->ev_probe(channel);
}
static inline int efx_nic_init_eventq(struct efx_channel *channel)
{
return channel->efx->type->ev_init(channel);
}
static inline void efx_nic_fini_eventq(struct efx_channel *channel)
{
channel->efx->type->ev_fini(channel);
}
static inline void efx_nic_remove_eventq(struct efx_channel *channel)
{
channel->efx->type->ev_remove(channel);
}
static inline int
efx_nic_process_eventq(struct efx_channel *channel, int quota)
{
return channel->efx->type->ev_process(channel, quota);
}
static inline void efx_nic_eventq_read_ack(struct efx_channel *channel)
{
channel->efx->type->ev_read_ack(channel);
}
void efx_nic_event_test_start(struct efx_channel *channel);
bool efx_nic_event_present(struct efx_channel *channel);
static inline void efx_sensor_event(struct efx_nic *efx, efx_qword_t *ev)
{
if (efx->type->sensor_event)
efx->type->sensor_event(efx, ev);
}
/* Some statistics are computed as A - B where A and B each increase
* linearly with some hardware counter(s) and the counters are read
* asynchronously. If the counters contributing to B are always read
* after those contributing to A, the computed value may be lower than
* the true value by some variable amount, and may decrease between
* subsequent computations.
*
* We should never allow statistics to decrease or to exceed the true
* value. Since the computed value will never be greater than the
* true value, we can achieve this by only storing the computed value
* when it increases.
*/
static inline void efx_update_diff_stat(u64 *stat, u64 diff)
{
if ((s64)(diff - *stat) > 0)
*stat = diff;
}
/* Interrupts */
int efx_nic_init_interrupt(struct efx_nic *efx);
int efx_nic_irq_test_start(struct efx_nic *efx);
void efx_nic_fini_interrupt(struct efx_nic *efx);
static inline int efx_nic_event_test_irq_cpu(struct efx_channel *channel)
{
return READ_ONCE(channel->event_test_cpu);
}
static inline int efx_nic_irq_test_irq_cpu(struct efx_nic *efx)
{
return READ_ONCE(efx->last_irq_cpu);
}
/* Global Resources */
int efx_nic_alloc_buffer(struct efx_nic *efx, struct efx_buffer *buffer,
unsigned int len, gfp_t gfp_flags);
void efx_nic_free_buffer(struct efx_nic *efx, struct efx_buffer *buffer);
size_t efx_nic_get_regs_len(struct efx_nic *efx);
void efx_nic_get_regs(struct efx_nic *efx, void *buf);
#define EFX_MC_STATS_GENERATION_INVALID ((__force __le64)(-1))
size_t efx_nic_describe_stats(const struct efx_hw_stat_desc *desc, size_t count,
const unsigned long *mask, u8 *names);
int efx_nic_copy_stats(struct efx_nic *efx, __le64 *dest);
void efx_nic_update_stats(const struct efx_hw_stat_desc *desc, size_t count,
const unsigned long *mask, u64 *stats,
const void *dma_buf, bool accumulate);
void efx_nic_fix_nodesc_drop_stat(struct efx_nic *efx, u64 *stat);
#define EFX_MAX_FLUSH_TIME 5000
#endif /* EFX_NIC_COMMON_H */