xref: /linux/drivers/net/ethernet/sfc/nic_common.h (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /****************************************************************************
3  * Driver for Solarflare network controllers and boards
4  * Copyright 2005-2006 Fen Systems Ltd.
5  * Copyright 2006-2013 Solarflare Communications Inc.
6  * Copyright 2019-2020 Xilinx Inc.
7  */
8 
9 #ifndef EFX_NIC_COMMON_H
10 #define EFX_NIC_COMMON_H
11 
12 #include "net_driver.h"
13 #include "efx_common.h"
14 #include "mcdi.h"
15 #include "ptp.h"
16 
17 enum {
18 	/* Revisions 0-3 were Falcon A0, A1, B0 and Siena respectively.
19 	 * They are not supported by this driver but these revision numbers
20 	 * form part of the ethtool API for register dumping.
21 	 */
22 	EFX_REV_HUNT_A0 = 4,
23 	EFX_REV_EF100 = 5,
24 	EFX_REV_X4 = 6,
25 };
26 
27 static inline int efx_nic_rev(struct efx_nic *efx)
28 {
29 	return efx->type->revision;
30 }
31 
32 /* Read the current event from the event queue */
33 static inline efx_qword_t *efx_event(struct efx_channel *channel,
34 				     unsigned int index)
35 {
36 	return ((efx_qword_t *)(channel->eventq.addr)) +
37 		(index & channel->eventq_mask);
38 }
39 
40 /* See if an event is present
41  *
42  * We check both the high and low dword of the event for all ones.  We
43  * wrote all ones when we cleared the event, and no valid event can
44  * have all ones in either its high or low dwords.  This approach is
45  * robust against reordering.
46  *
47  * Note that using a single 64-bit comparison is incorrect; even
48  * though the CPU read will be atomic, the DMA write may not be.
49  */
50 static inline int efx_event_present(efx_qword_t *event)
51 {
52 	return !(EFX_DWORD_IS_ALL_ONES(event->dword[0]) |
53 		  EFX_DWORD_IS_ALL_ONES(event->dword[1]));
54 }
55 
56 /* Returns a pointer to the specified transmit descriptor in the TX
57  * descriptor queue belonging to the specified channel.
58  */
59 static inline efx_qword_t *
60 efx_tx_desc(struct efx_tx_queue *tx_queue, unsigned int index)
61 {
62 	return ((efx_qword_t *)(tx_queue->txd.addr)) + index;
63 }
64 
65 /* Report whether this TX queue would be empty for the given write_count.
66  * May return false negative.
67  */
68 static inline bool efx_nic_tx_is_empty(struct efx_tx_queue *tx_queue, unsigned int write_count)
69 {
70 	unsigned int empty_read_count = READ_ONCE(tx_queue->empty_read_count);
71 
72 	if (empty_read_count == 0)
73 		return false;
74 
75 	return ((empty_read_count ^ write_count) & ~EFX_EMPTY_COUNT_VALID) == 0;
76 }
77 
78 int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue, struct sk_buff *skb,
79 			bool *data_mapped);
80 
81 /* Decide whether to push a TX descriptor to the NIC vs merely writing
82  * the doorbell.  This can reduce latency when we are adding a single
83  * descriptor to an empty queue, but is otherwise pointless.
84  * We use the write_count used for the last doorbell push, to get the
85  * NIC's view of the tx queue.
86  */
87 static inline bool efx_nic_may_push_tx_desc(struct efx_tx_queue *tx_queue,
88 					    unsigned int write_count)
89 {
90 	bool was_empty = efx_nic_tx_is_empty(tx_queue, write_count);
91 
92 	tx_queue->empty_read_count = 0;
93 	return was_empty && tx_queue->write_count - write_count == 1;
94 }
95 
96 /* Returns a pointer to the specified descriptor in the RX descriptor queue */
97 static inline efx_qword_t *
98 efx_rx_desc(struct efx_rx_queue *rx_queue, unsigned int index)
99 {
100 	return ((efx_qword_t *)(rx_queue->rxd.addr)) + index;
101 }
102 
103 /* Alignment of PCIe DMA boundaries (4KB) */
104 #define EFX_PAGE_SIZE	4096
105 /* Size and alignment of buffer table entries (same) */
106 #define EFX_BUF_SIZE	EFX_PAGE_SIZE
107 
108 /* NIC-generic software stats */
109 enum {
110 	GENERIC_STAT_rx_noskb_drops,
111 	GENERIC_STAT_rx_nodesc_trunc,
112 	GENERIC_STAT_COUNT
113 };
114 
115 #define EFX_GENERIC_SW_STAT(ext_name)				\
116 	[GENERIC_STAT_ ## ext_name] = { #ext_name, 0, 0 }
117 
118 /* TX data path */
119 static inline int efx_nic_probe_tx(struct efx_tx_queue *tx_queue)
120 {
121 	return tx_queue->efx->type->tx_probe(tx_queue);
122 }
123 static inline void efx_nic_init_tx(struct efx_tx_queue *tx_queue)
124 {
125 	tx_queue->efx->type->tx_init(tx_queue);
126 }
127 static inline void efx_nic_remove_tx(struct efx_tx_queue *tx_queue)
128 {
129 	if (tx_queue->efx->type->tx_remove)
130 		tx_queue->efx->type->tx_remove(tx_queue);
131 }
132 static inline void efx_nic_push_buffers(struct efx_tx_queue *tx_queue)
133 {
134 	tx_queue->efx->type->tx_write(tx_queue);
135 }
136 
137 /* RX data path */
138 static inline int efx_nic_probe_rx(struct efx_rx_queue *rx_queue)
139 {
140 	return rx_queue->efx->type->rx_probe(rx_queue);
141 }
142 static inline void efx_nic_init_rx(struct efx_rx_queue *rx_queue)
143 {
144 	rx_queue->efx->type->rx_init(rx_queue);
145 }
146 static inline void efx_nic_remove_rx(struct efx_rx_queue *rx_queue)
147 {
148 	rx_queue->efx->type->rx_remove(rx_queue);
149 }
150 static inline void efx_nic_notify_rx_desc(struct efx_rx_queue *rx_queue)
151 {
152 	rx_queue->efx->type->rx_write(rx_queue);
153 }
154 static inline void efx_nic_generate_fill_event(struct efx_rx_queue *rx_queue)
155 {
156 	rx_queue->efx->type->rx_defer_refill(rx_queue);
157 }
158 
159 /* Event data path */
160 static inline int efx_nic_probe_eventq(struct efx_channel *channel)
161 {
162 	return channel->efx->type->ev_probe(channel);
163 }
164 static inline int efx_nic_init_eventq(struct efx_channel *channel)
165 {
166 	return channel->efx->type->ev_init(channel);
167 }
168 static inline void efx_nic_fini_eventq(struct efx_channel *channel)
169 {
170 	channel->efx->type->ev_fini(channel);
171 }
172 static inline void efx_nic_remove_eventq(struct efx_channel *channel)
173 {
174 	channel->efx->type->ev_remove(channel);
175 }
176 static inline int
177 efx_nic_process_eventq(struct efx_channel *channel, int quota)
178 {
179 	return channel->efx->type->ev_process(channel, quota);
180 }
181 static inline void efx_nic_eventq_read_ack(struct efx_channel *channel)
182 {
183 	channel->efx->type->ev_read_ack(channel);
184 }
185 
186 void efx_nic_event_test_start(struct efx_channel *channel);
187 
188 bool efx_nic_event_present(struct efx_channel *channel);
189 
190 static inline void efx_sensor_event(struct efx_nic *efx, efx_qword_t *ev)
191 {
192 	if (efx->type->sensor_event)
193 		efx->type->sensor_event(efx, ev);
194 }
195 
196 static inline unsigned int efx_rx_recycle_ring_size(const struct efx_nic *efx)
197 {
198 	return efx->type->rx_recycle_ring_size(efx);
199 }
200 
201 /* Some statistics are computed as A - B where A and B each increase
202  * linearly with some hardware counter(s) and the counters are read
203  * asynchronously.  If the counters contributing to B are always read
204  * after those contributing to A, the computed value may be lower than
205  * the true value by some variable amount, and may decrease between
206  * subsequent computations.
207  *
208  * We should never allow statistics to decrease or to exceed the true
209  * value.  Since the computed value will never be greater than the
210  * true value, we can achieve this by only storing the computed value
211  * when it increases.
212  */
213 static inline void efx_update_diff_stat(u64 *stat, u64 diff)
214 {
215 	if ((s64)(diff - *stat) > 0)
216 		*stat = diff;
217 }
218 
219 /* Interrupts */
220 int efx_nic_init_interrupt(struct efx_nic *efx);
221 int efx_nic_irq_test_start(struct efx_nic *efx);
222 void efx_nic_fini_interrupt(struct efx_nic *efx);
223 
224 static inline int efx_nic_event_test_irq_cpu(struct efx_channel *channel)
225 {
226 	return READ_ONCE(channel->event_test_cpu);
227 }
228 static inline int efx_nic_irq_test_irq_cpu(struct efx_nic *efx)
229 {
230 	return READ_ONCE(efx->last_irq_cpu);
231 }
232 
233 /* Global Resources */
234 int efx_nic_alloc_buffer(struct efx_nic *efx, struct efx_buffer *buffer,
235 			 unsigned int len, gfp_t gfp_flags);
236 void efx_nic_free_buffer(struct efx_nic *efx, struct efx_buffer *buffer);
237 
238 size_t efx_nic_get_regs_len(struct efx_nic *efx);
239 void efx_nic_get_regs(struct efx_nic *efx, void *buf);
240 
241 #define EFX_MC_STATS_GENERATION_INVALID ((__force __le64)(-1))
242 
243 size_t efx_nic_describe_stats(const struct efx_hw_stat_desc *desc, size_t count,
244 			      const unsigned long *mask, u8 **names);
245 int efx_nic_copy_stats(struct efx_nic *efx, __le64 *dest);
246 void efx_nic_update_stats(const struct efx_hw_stat_desc *desc, size_t count,
247 			  const unsigned long *mask, u64 *stats,
248 			  const void *dma_buf, bool accumulate);
249 void efx_nic_fix_nodesc_drop_stat(struct efx_nic *efx, u64 *stat);
250 static inline size_t efx_nic_update_stats_atomic(struct efx_nic *efx, u64 *full_stats,
251 						 struct rtnl_link_stats64 *core_stats)
252 {
253 	if (efx->type->update_stats_atomic)
254 		return efx->type->update_stats_atomic(efx, full_stats, core_stats);
255 	return efx->type->update_stats(efx, full_stats, core_stats);
256 }
257 
258 #define EFX_MAX_FLUSH_TIME 5000
259 
260 #endif /* EFX_NIC_COMMON_H */
261