xref: /freebsd/sys/contrib/ena-com/ena_eth_com.h (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2015-2023 Amazon.com, Inc. or its affiliates.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * * Redistributions of source code must retain the above copyright
12  * notice, this list of conditions and the following disclaimer.
13  * * Redistributions in binary form must reproduce the above copyright
14  * notice, this list of conditions and the following disclaimer in
15  * the documentation and/or other materials provided with the
16  * distribution.
17  * * Neither the name of copyright holder nor the names of its
18  * contributors may be used to endorse or promote products derived
19  * from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #ifndef ENA_ETH_COM_H_
35 #define ENA_ETH_COM_H_
36 
37 #if defined(__cplusplus)
38 extern "C" {
39 #endif
40 #include "ena_com.h"
41 
42 struct ena_com_tx_ctx {
43 	struct ena_com_tx_meta ena_meta;
44 	struct ena_com_buf *ena_bufs;
45 	/* For LLQ, header buffer - pushed to the device mem space */
46 	void *push_header;
47 
48 	enum ena_eth_io_l3_proto_index l3_proto;
49 	enum ena_eth_io_l4_proto_index l4_proto;
50 	u16 num_bufs;
51 	u16 req_id;
52 	/* For regular queue, indicate the size of the header
53 	 * For LLQ, indicate the size of the pushed buffer
54 	 */
55 	u16 header_len;
56 
57 	u8 meta_valid;
58 	u8 tso_enable;
59 	u8 l3_csum_enable;
60 	u8 l4_csum_enable;
61 	u8 l4_csum_partial;
62 	u8 df; /* Don't fragment */
63 };
64 
65 struct ena_com_rx_ctx {
66 	struct ena_com_rx_buf_info *ena_bufs;
67 	enum ena_eth_io_l3_proto_index l3_proto;
68 	enum ena_eth_io_l4_proto_index l4_proto;
69 	bool l3_csum_err;
70 	bool l4_csum_err;
71 	u8 l4_csum_checked;
72 	/* fragmented packet */
73 	bool frag;
74 	u32 hash;
75 	u16 descs;
76 	u16 max_bufs;
77 	u8 pkt_offset;
78 };
79 
80 int ena_com_prepare_tx(struct ena_com_io_sq *io_sq,
81 		       struct ena_com_tx_ctx *ena_tx_ctx,
82 		       int *nb_hw_desc);
83 
84 int ena_com_rx_pkt(struct ena_com_io_cq *io_cq,
85 		   struct ena_com_io_sq *io_sq,
86 		   struct ena_com_rx_ctx *ena_rx_ctx);
87 
88 int ena_com_add_single_rx_desc(struct ena_com_io_sq *io_sq,
89 			       struct ena_com_buf *ena_buf,
90 			       u16 req_id);
91 
92 bool ena_com_cq_empty(struct ena_com_io_cq *io_cq);
93 
94 static inline void ena_com_unmask_intr(struct ena_com_io_cq *io_cq,
95 				       struct ena_eth_io_intr_reg *intr_reg)
96 {
97 	ENA_REG_WRITE32(io_cq->bus, intr_reg->intr_control, io_cq->unmask_reg);
98 }
99 
100 static inline int ena_com_free_q_entries(struct ena_com_io_sq *io_sq)
101 {
102 	u16 tail, next_to_comp, cnt;
103 
104 	next_to_comp = io_sq->next_to_comp;
105 	tail = io_sq->tail;
106 	cnt = tail - next_to_comp;
107 
108 	return io_sq->q_depth - 1 - cnt;
109 }
110 
111 /* Check if the submission queue has enough space to hold required_buffers */
112 static inline bool ena_com_sq_have_enough_space(struct ena_com_io_sq *io_sq,
113 						u16 required_buffers)
114 {
115 	int temp;
116 
117 	if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST)
118 		return ena_com_free_q_entries(io_sq) >= required_buffers;
119 
120 	/* This calculation doesn't need to be 100% accurate. So to reduce
121 	 * the calculation overhead just Subtract 2 lines from the free descs
122 	 * (one for the header line and one to compensate the devision
123 	 * down calculation.
124 	 */
125 	temp = required_buffers / io_sq->llq_info.descs_per_entry + 2;
126 
127 	return ena_com_free_q_entries(io_sq) > temp;
128 }
129 
130 static inline bool ena_com_meta_desc_changed(struct ena_com_io_sq *io_sq,
131 					     struct ena_com_tx_ctx *ena_tx_ctx)
132 {
133 	if (!ena_tx_ctx->meta_valid)
134 		return false;
135 
136 	return !!memcmp(&io_sq->cached_tx_meta,
137 			&ena_tx_ctx->ena_meta,
138 			sizeof(struct ena_com_tx_meta));
139 }
140 
141 static inline bool is_llq_max_tx_burst_exists(struct ena_com_io_sq *io_sq)
142 {
143 	return (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) &&
144 	       io_sq->llq_info.max_entries_in_tx_burst > 0;
145 }
146 
147 static inline bool ena_com_is_doorbell_needed(struct ena_com_io_sq *io_sq,
148 					      struct ena_com_tx_ctx *ena_tx_ctx)
149 {
150 	struct ena_com_llq_info *llq_info;
151 	int descs_after_first_entry;
152 	int num_entries_needed = 1;
153 	u16 num_descs;
154 
155 	if (!is_llq_max_tx_burst_exists(io_sq))
156 		return false;
157 
158 	llq_info = &io_sq->llq_info;
159 	num_descs = ena_tx_ctx->num_bufs;
160 
161 	if (llq_info->disable_meta_caching ||
162 	    unlikely(ena_com_meta_desc_changed(io_sq, ena_tx_ctx)))
163 		++num_descs;
164 
165 	if (num_descs > llq_info->descs_num_before_header) {
166 		descs_after_first_entry = num_descs - llq_info->descs_num_before_header;
167 		num_entries_needed += DIV_ROUND_UP(descs_after_first_entry,
168 						   llq_info->descs_per_entry);
169 	}
170 
171 	ena_trc_dbg(ena_com_io_sq_to_ena_dev(io_sq),
172 		    "Queue: %d num_descs: %d num_entries_needed: %d\n",
173 		    io_sq->qid, num_descs, num_entries_needed);
174 
175 	return num_entries_needed > io_sq->entries_in_tx_burst_left;
176 }
177 
178 static inline int ena_com_write_sq_doorbell(struct ena_com_io_sq *io_sq)
179 {
180 	u16 max_entries_in_tx_burst = io_sq->llq_info.max_entries_in_tx_burst;
181 	u16 tail = io_sq->tail;
182 
183 	ena_trc_dbg(ena_com_io_sq_to_ena_dev(io_sq),
184 		    "Write submission queue doorbell for queue: %d tail: %d\n",
185 		    io_sq->qid, tail);
186 
187 	ENA_REG_WRITE32(io_sq->bus, tail, io_sq->db_addr);
188 
189 	if (is_llq_max_tx_burst_exists(io_sq)) {
190 		ena_trc_dbg(ena_com_io_sq_to_ena_dev(io_sq),
191 			    "Reset available entries in tx burst for queue %d to %d\n",
192 			    io_sq->qid, max_entries_in_tx_burst);
193 		io_sq->entries_in_tx_burst_left = max_entries_in_tx_burst;
194 	}
195 
196 	return 0;
197 }
198 
199 static inline void ena_com_update_numa_node(struct ena_com_io_cq *io_cq,
200 					    u8 numa_node)
201 {
202 	struct ena_eth_io_numa_node_cfg_reg numa_cfg;
203 
204 	if (!io_cq->numa_node_cfg_reg)
205 		return;
206 
207 	numa_cfg.numa_cfg = (numa_node & ENA_ETH_IO_NUMA_NODE_CFG_REG_NUMA_MASK)
208 		| ENA_ETH_IO_NUMA_NODE_CFG_REG_ENABLED_MASK;
209 
210 	ENA_REG_WRITE32(io_cq->bus, numa_cfg.numa_cfg, io_cq->numa_node_cfg_reg);
211 }
212 
213 static inline void ena_com_comp_ack(struct ena_com_io_sq *io_sq, u16 elem)
214 {
215 	io_sq->next_to_comp += elem;
216 }
217 
218 static inline void ena_com_cq_inc_head(struct ena_com_io_cq *io_cq)
219 {
220 	io_cq->head++;
221 
222 	/* Switch phase bit in case of wrap around */
223 	if (unlikely((io_cq->head & (io_cq->q_depth - 1)) == 0))
224 		io_cq->phase ^= 1;
225 }
226 
227 static inline int ena_com_tx_comp_req_id_get(struct ena_com_io_cq *io_cq,
228 					     u16 *req_id)
229 {
230 	u8 expected_phase, cdesc_phase;
231 	struct ena_eth_io_tx_cdesc *cdesc;
232 	u16 masked_head;
233 
234 	masked_head = io_cq->head & (io_cq->q_depth - 1);
235 	expected_phase = io_cq->phase;
236 
237 	cdesc = (struct ena_eth_io_tx_cdesc *)
238 		((uintptr_t)io_cq->cdesc_addr.virt_addr +
239 		(masked_head * io_cq->cdesc_entry_size_in_bytes));
240 
241 	/* When the current completion descriptor phase isn't the same as the
242 	 * expected, it mean that the device still didn't update
243 	 * this completion.
244 	 */
245 	cdesc_phase = READ_ONCE16(cdesc->flags) & ENA_ETH_IO_TX_CDESC_PHASE_MASK;
246 	if (cdesc_phase != expected_phase)
247 		return ENA_COM_TRY_AGAIN;
248 
249 	dma_rmb();
250 
251 	*req_id = READ_ONCE16(cdesc->req_id);
252 	if (unlikely(*req_id >= io_cq->q_depth)) {
253 		ena_trc_err(ena_com_io_cq_to_ena_dev(io_cq),
254 			    "Invalid req id %d\n", cdesc->req_id);
255 		return ENA_COM_INVAL;
256 	}
257 
258 	ena_com_cq_inc_head(io_cq);
259 
260 	return 0;
261 }
262 
263 #if defined(__cplusplus)
264 }
265 #endif
266 #endif /* ENA_ETH_COM_H_ */
267