xref: /linux/drivers/net/ethernet/sfc/siena/nic_common.h (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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 0-2 were Falcon A0, A1 and B0 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_SIENA_A0 = 3,
23 	EFX_REV_HUNT_A0 = 4,
24 	EFX_REV_EF100 = 5,
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.buf.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.buf.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 /* Decide whether to push a TX descriptor to the NIC vs merely writing
79  * the doorbell.  This can reduce latency when we are adding a single
80  * descriptor to an empty queue, but is otherwise pointless.  Further,
81  * Falcon and Siena have hardware bugs (SF bug 33851) that may be
82  * triggered if we don't check this.
83  * We use the write_count used for the last doorbell push, to get the
84  * NIC's view of the tx queue.
85  */
86 static inline bool efx_nic_may_push_tx_desc(struct efx_tx_queue *tx_queue,
87 					    unsigned int write_count)
88 {
89 	bool was_empty = efx_nic_tx_is_empty(tx_queue, write_count);
90 
91 	tx_queue->empty_read_count = 0;
92 	return was_empty && tx_queue->write_count - write_count == 1;
93 }
94 
95 /* Returns a pointer to the specified descriptor in the RX descriptor queue */
96 static inline efx_qword_t *
97 efx_rx_desc(struct efx_rx_queue *rx_queue, unsigned int index)
98 {
99 	return ((efx_qword_t *) (rx_queue->rxd.buf.addr)) + index;
100 }
101 
102 /* Alignment of PCIe DMA boundaries (4KB) */
103 #define EFX_PAGE_SIZE	4096
104 /* Size and alignment of buffer table entries (same) */
105 #define EFX_BUF_SIZE	EFX_PAGE_SIZE
106 
107 /* NIC-generic software stats */
108 enum {
109 	GENERIC_STAT_rx_noskb_drops,
110 	GENERIC_STAT_rx_nodesc_trunc,
111 	GENERIC_STAT_COUNT
112 };
113 
114 #define EFX_GENERIC_SW_STAT(ext_name)				\
115 	[GENERIC_STAT_ ## ext_name] = { #ext_name, 0, 0 }
116 
117 /* TX data path */
118 static inline int efx_nic_probe_tx(struct efx_tx_queue *tx_queue)
119 {
120 	return tx_queue->efx->type->tx_probe(tx_queue);
121 }
122 static inline void efx_nic_init_tx(struct efx_tx_queue *tx_queue)
123 {
124 	tx_queue->efx->type->tx_init(tx_queue);
125 }
126 static inline void efx_nic_remove_tx(struct efx_tx_queue *tx_queue)
127 {
128 	if (tx_queue->efx->type->tx_remove)
129 		tx_queue->efx->type->tx_remove(tx_queue);
130 }
131 static inline void efx_nic_push_buffers(struct efx_tx_queue *tx_queue)
132 {
133 	tx_queue->efx->type->tx_write(tx_queue);
134 }
135 
136 /* RX data path */
137 static inline int efx_nic_probe_rx(struct efx_rx_queue *rx_queue)
138 {
139 	return rx_queue->efx->type->rx_probe(rx_queue);
140 }
141 static inline void efx_nic_init_rx(struct efx_rx_queue *rx_queue)
142 {
143 	rx_queue->efx->type->rx_init(rx_queue);
144 }
145 static inline void efx_nic_remove_rx(struct efx_rx_queue *rx_queue)
146 {
147 	rx_queue->efx->type->rx_remove(rx_queue);
148 }
149 static inline void efx_nic_notify_rx_desc(struct efx_rx_queue *rx_queue)
150 {
151 	rx_queue->efx->type->rx_write(rx_queue);
152 }
153 static inline void efx_nic_generate_fill_event(struct efx_rx_queue *rx_queue)
154 {
155 	rx_queue->efx->type->rx_defer_refill(rx_queue);
156 }
157 
158 /* Event data path */
159 static inline int efx_nic_probe_eventq(struct efx_channel *channel)
160 {
161 	return channel->efx->type->ev_probe(channel);
162 }
163 static inline int efx_nic_init_eventq(struct efx_channel *channel)
164 {
165 	return channel->efx->type->ev_init(channel);
166 }
167 static inline void efx_nic_fini_eventq(struct efx_channel *channel)
168 {
169 	channel->efx->type->ev_fini(channel);
170 }
171 static inline void efx_nic_remove_eventq(struct efx_channel *channel)
172 {
173 	channel->efx->type->ev_remove(channel);
174 }
175 static inline int
176 efx_nic_process_eventq(struct efx_channel *channel, int quota)
177 {
178 	return channel->efx->type->ev_process(channel, quota);
179 }
180 static inline void efx_nic_eventq_read_ack(struct efx_channel *channel)
181 {
182 	channel->efx->type->ev_read_ack(channel);
183 }
184 
185 void efx_siena_event_test_start(struct efx_channel *channel);
186 
187 bool efx_siena_event_present(struct efx_channel *channel);
188 
189 static inline void efx_sensor_event(struct efx_nic *efx, efx_qword_t *ev)
190 {
191 	if (efx->type->sensor_event)
192 		efx->type->sensor_event(efx, ev);
193 }
194 
195 static inline unsigned int efx_rx_recycle_ring_size(const struct efx_nic *efx)
196 {
197 	return efx->type->rx_recycle_ring_size(efx);
198 }
199 
200 /* Some statistics are computed as A - B where A and B each increase
201  * linearly with some hardware counter(s) and the counters are read
202  * asynchronously.  If the counters contributing to B are always read
203  * after those contributing to A, the computed value may be lower than
204  * the true value by some variable amount, and may decrease between
205  * subsequent computations.
206  *
207  * We should never allow statistics to decrease or to exceed the true
208  * value.  Since the computed value will never be greater than the
209  * true value, we can achieve this by only storing the computed value
210  * when it increases.
211  */
212 static inline void efx_update_diff_stat(u64 *stat, u64 diff)
213 {
214 	if ((s64)(diff - *stat) > 0)
215 		*stat = diff;
216 }
217 
218 /* Interrupts */
219 int efx_siena_init_interrupt(struct efx_nic *efx);
220 int efx_siena_irq_test_start(struct efx_nic *efx);
221 void efx_siena_fini_interrupt(struct efx_nic *efx);
222 
223 static inline int efx_nic_event_test_irq_cpu(struct efx_channel *channel)
224 {
225 	return READ_ONCE(channel->event_test_cpu);
226 }
227 static inline int efx_nic_irq_test_irq_cpu(struct efx_nic *efx)
228 {
229 	return READ_ONCE(efx->last_irq_cpu);
230 }
231 
232 /* Global Resources */
233 int efx_siena_alloc_buffer(struct efx_nic *efx, struct efx_buffer *buffer,
234 			   unsigned int len, gfp_t gfp_flags);
235 void efx_siena_free_buffer(struct efx_nic *efx, struct efx_buffer *buffer);
236 
237 size_t efx_siena_get_regs_len(struct efx_nic *efx);
238 void efx_siena_get_regs(struct efx_nic *efx, void *buf);
239 
240 #define EFX_MC_STATS_GENERATION_INVALID ((__force __le64)(-1))
241 
242 size_t efx_siena_describe_stats(const struct efx_hw_stat_desc *desc, size_t count,
243 				const unsigned long *mask, u8 *names);
244 void efx_siena_update_stats(const struct efx_hw_stat_desc *desc, size_t count,
245 			    const unsigned long *mask, u64 *stats,
246 			    const void *dma_buf, bool accumulate);
247 void efx_siena_fix_nodesc_drop_stat(struct efx_nic *efx, u64 *stat);
248 
249 #define EFX_MAX_FLUSH_TIME 5000
250 
251 #endif /* EFX_NIC_COMMON_H */
252