drivers/net/ethernet/sfc/siena/nic_common.h - linux - Git at Google

 /* 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;
 }

 /* 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_siena_event_test_start(struct efx_channel *channel);

 bool efx_siena_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);
 }

 static inline unsigned int efx_rx_recycle_ring_size(const struct efx_nic *efx)
 {
 	return efx->type->rx_recycle_ring_size(efx);
 }

 /* 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_siena_init_interrupt(struct efx_nic *efx);
 int efx_siena_irq_test_start(struct efx_nic *efx);
 void efx_siena_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_siena_alloc_buffer(struct efx_nic *efx, struct efx_buffer *buffer,
 			   unsigned int len, gfp_t gfp_flags);
 void efx_siena_free_buffer(struct efx_nic *efx, struct efx_buffer *buffer);

 size_t efx_siena_get_regs_len(struct efx_nic *efx);
 void efx_siena_get_regs(struct efx_nic *efx, void *buf);

 #define EFX_MC_STATS_GENERATION_INVALID ((__force __le64)(-1))

 size_t efx_siena_describe_stats(const struct efx_hw_stat_desc *desc, size_t count,
 				const unsigned long *mask, u8 *names);
 void efx_siena_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_siena_fix_nodesc_drop_stat(struct efx_nic *efx, u64 *stat);

 #define EFX_MAX_FLUSH_TIME 5000

 #endif /* EFX_NIC_COMMON_H */
	/* 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;
	}

	/* 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_siena_event_test_start(struct efx_channel *channel);

	bool efx_siena_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);
	}

	static inline unsigned int efx_rx_recycle_ring_size(const struct efx_nic *efx)
	{
	return efx->type->rx_recycle_ring_size(efx);
	}

	/* 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_siena_init_interrupt(struct efx_nic *efx);
	int efx_siena_irq_test_start(struct efx_nic *efx);
	void efx_siena_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_siena_alloc_buffer(struct efx_nic efx, struct efx_buffer buffer,
	unsigned int len, gfp_t gfp_flags);
	void efx_siena_free_buffer(struct efx_nic efx, struct efx_buffer buffer);

	size_t efx_siena_get_regs_len(struct efx_nic *efx);
	void efx_siena_get_regs(struct efx_nic efx, void buf);

	#define EFX_MC_STATS_GENERATION_INVALID ((__force __le64)(-1))

	size_t efx_siena_describe_stats(const struct efx_hw_stat_desc *desc, size_t count,
	const unsigned long mask, u8 names);
	void efx_siena_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_siena_fix_nodesc_drop_stat(struct efx_nic efx, u64 stat);

	#define EFX_MAX_FLUSH_TIME 5000

	#endif /* EFX_NIC_COMMON_H */