xref: /dpdk/drivers/net/ena/base/ena_eth_com.h (revision 68a03efeed657e6e05f281479b33b51102797e15)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright (c) 2015-2020 Amazon.com, Inc. or its affiliates.
3  * All rights reserved.
4  */
5 
6 #ifndef ENA_ETH_COM_H_
7 #define ENA_ETH_COM_H_
8 
9 #if defined(__cplusplus)
10 extern "C" {
11 #endif
12 #include "ena_com.h"
13 
14 /* head update threshold in units of (queue size / ENA_COMP_HEAD_THRESH) */
15 #define ENA_COMP_HEAD_THRESH 4
16 
17 struct ena_com_tx_ctx {
18 	struct ena_com_tx_meta ena_meta;
19 	struct ena_com_buf *ena_bufs;
20 	/* For LLQ, header buffer - pushed to the device mem space */
21 	void *push_header;
22 
23 	enum ena_eth_io_l3_proto_index l3_proto;
24 	enum ena_eth_io_l4_proto_index l4_proto;
25 	u16 num_bufs;
26 	u16 req_id;
27 	/* For regular queue, indicate the size of the header
28 	 * For LLQ, indicate the size of the pushed buffer
29 	 */
30 	u16 header_len;
31 
32 	u8 meta_valid;
33 	u8 tso_enable;
34 	u8 l3_csum_enable;
35 	u8 l4_csum_enable;
36 	u8 l4_csum_partial;
37 	u8 df; /* Don't fragment */
38 };
39 
40 struct ena_com_rx_ctx {
41 	struct ena_com_rx_buf_info *ena_bufs;
42 	enum ena_eth_io_l3_proto_index l3_proto;
43 	enum ena_eth_io_l4_proto_index l4_proto;
44 	bool l3_csum_err;
45 	bool l4_csum_err;
46 	u8 l4_csum_checked;
47 	/* fragmented packet */
48 	bool frag;
49 	u32 hash;
50 	u16 descs;
51 	int max_bufs;
52 	u8 pkt_offset;
53 };
54 
55 int ena_com_prepare_tx(struct ena_com_io_sq *io_sq,
56 		       struct ena_com_tx_ctx *ena_tx_ctx,
57 		       int *nb_hw_desc);
58 
59 int ena_com_rx_pkt(struct ena_com_io_cq *io_cq,
60 		   struct ena_com_io_sq *io_sq,
61 		   struct ena_com_rx_ctx *ena_rx_ctx);
62 
63 int ena_com_add_single_rx_desc(struct ena_com_io_sq *io_sq,
64 			       struct ena_com_buf *ena_buf,
65 			       u16 req_id);
66 
67 bool ena_com_cq_empty(struct ena_com_io_cq *io_cq);
68 
69 static inline void ena_com_unmask_intr(struct ena_com_io_cq *io_cq,
70 				       struct ena_eth_io_intr_reg *intr_reg)
71 {
72 	ENA_REG_WRITE32(io_cq->bus, intr_reg->intr_control, io_cq->unmask_reg);
73 }
74 
75 static inline int ena_com_free_q_entries(struct ena_com_io_sq *io_sq)
76 {
77 	u16 tail, next_to_comp, cnt;
78 
79 	next_to_comp = io_sq->next_to_comp;
80 	tail = io_sq->tail;
81 	cnt = tail - next_to_comp;
82 
83 	return io_sq->q_depth - 1 - cnt;
84 }
85 
86 /* Check if the submission queue has enough space to hold required_buffers */
87 static inline bool ena_com_sq_have_enough_space(struct ena_com_io_sq *io_sq,
88 						u16 required_buffers)
89 {
90 	int temp;
91 
92 	if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST)
93 		return ena_com_free_q_entries(io_sq) >= required_buffers;
94 
95 	/* This calculation doesn't need to be 100% accurate. So to reduce
96 	 * the calculation overhead just Subtract 2 lines from the free descs
97 	 * (one for the header line and one to compensate the devision
98 	 * down calculation.
99 	 */
100 	temp = required_buffers / io_sq->llq_info.descs_per_entry + 2;
101 
102 	return ena_com_free_q_entries(io_sq) > temp;
103 }
104 
105 static inline bool ena_com_meta_desc_changed(struct ena_com_io_sq *io_sq,
106 					     struct ena_com_tx_ctx *ena_tx_ctx)
107 {
108 	if (!ena_tx_ctx->meta_valid)
109 		return false;
110 
111 	return !!memcmp(&io_sq->cached_tx_meta,
112 			&ena_tx_ctx->ena_meta,
113 			sizeof(struct ena_com_tx_meta));
114 }
115 
116 static inline bool is_llq_max_tx_burst_exists(struct ena_com_io_sq *io_sq)
117 {
118 	return (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) &&
119 	       io_sq->llq_info.max_entries_in_tx_burst > 0;
120 }
121 
122 static inline bool ena_com_is_doorbell_needed(struct ena_com_io_sq *io_sq,
123 					      struct ena_com_tx_ctx *ena_tx_ctx)
124 {
125 	struct ena_com_llq_info *llq_info;
126 	int descs_after_first_entry;
127 	int num_entries_needed = 1;
128 	u16 num_descs;
129 
130 	if (!is_llq_max_tx_burst_exists(io_sq))
131 		return false;
132 
133 	llq_info = &io_sq->llq_info;
134 	num_descs = ena_tx_ctx->num_bufs;
135 
136 	if (llq_info->disable_meta_caching ||
137 	    unlikely(ena_com_meta_desc_changed(io_sq, ena_tx_ctx)))
138 		++num_descs;
139 
140 	if (num_descs > llq_info->descs_num_before_header) {
141 		descs_after_first_entry = num_descs - llq_info->descs_num_before_header;
142 		num_entries_needed += DIV_ROUND_UP(descs_after_first_entry,
143 						   llq_info->descs_per_entry);
144 	}
145 
146 	ena_trc_dbg("queue: %d num_descs: %d num_entries_needed: %d\n",
147 		    io_sq->qid, num_descs, num_entries_needed);
148 
149 	return num_entries_needed > io_sq->entries_in_tx_burst_left;
150 }
151 
152 static inline int ena_com_write_sq_doorbell(struct ena_com_io_sq *io_sq)
153 {
154 	u16 max_entries_in_tx_burst = io_sq->llq_info.max_entries_in_tx_burst;
155 	u16 tail = io_sq->tail;
156 
157 	ena_trc_dbg("write submission queue doorbell for queue: %d tail: %d\n",
158 		    io_sq->qid, tail);
159 
160 	ENA_REG_WRITE32(io_sq->bus, tail, io_sq->db_addr);
161 
162 	if (is_llq_max_tx_burst_exists(io_sq)) {
163 		ena_trc_dbg("reset available entries in tx burst for queue %d to %d\n",
164 			     io_sq->qid, max_entries_in_tx_burst);
165 		io_sq->entries_in_tx_burst_left = max_entries_in_tx_burst;
166 	}
167 
168 	return 0;
169 }
170 
171 static inline int ena_com_update_dev_comp_head(struct ena_com_io_cq *io_cq)
172 {
173 	u16 unreported_comp, head;
174 	bool need_update;
175 
176 	if (unlikely(io_cq->cq_head_db_reg)) {
177 		head = io_cq->head;
178 		unreported_comp = head - io_cq->last_head_update;
179 		need_update = unreported_comp > (io_cq->q_depth / ENA_COMP_HEAD_THRESH);
180 
181 		if (unlikely(need_update)) {
182 			ena_trc_dbg("Write completion queue doorbell for queue %d: head: %d\n",
183 				    io_cq->qid, head);
184 			ENA_REG_WRITE32(io_cq->bus, head, io_cq->cq_head_db_reg);
185 			io_cq->last_head_update = head;
186 		}
187 	}
188 
189 	return 0;
190 }
191 
192 static inline void ena_com_update_numa_node(struct ena_com_io_cq *io_cq,
193 					    u8 numa_node)
194 {
195 	struct ena_eth_io_numa_node_cfg_reg numa_cfg;
196 
197 	if (!io_cq->numa_node_cfg_reg)
198 		return;
199 
200 	numa_cfg.numa_cfg = (numa_node & ENA_ETH_IO_NUMA_NODE_CFG_REG_NUMA_MASK)
201 		| ENA_ETH_IO_NUMA_NODE_CFG_REG_ENABLED_MASK;
202 
203 	ENA_REG_WRITE32(io_cq->bus, numa_cfg.numa_cfg, io_cq->numa_node_cfg_reg);
204 }
205 
206 static inline void ena_com_comp_ack(struct ena_com_io_sq *io_sq, u16 elem)
207 {
208 	io_sq->next_to_comp += elem;
209 }
210 
211 static inline void ena_com_cq_inc_head(struct ena_com_io_cq *io_cq)
212 {
213 	io_cq->head++;
214 
215 	/* Switch phase bit in case of wrap around */
216 	if (unlikely((io_cq->head & (io_cq->q_depth - 1)) == 0))
217 		io_cq->phase ^= 1;
218 }
219 
220 static inline int ena_com_tx_comp_req_id_get(struct ena_com_io_cq *io_cq,
221 					     u16 *req_id)
222 {
223 	u8 expected_phase, cdesc_phase;
224 	struct ena_eth_io_tx_cdesc *cdesc;
225 	u16 masked_head;
226 
227 	masked_head = io_cq->head & (io_cq->q_depth - 1);
228 	expected_phase = io_cq->phase;
229 
230 	cdesc = (struct ena_eth_io_tx_cdesc *)
231 		((uintptr_t)io_cq->cdesc_addr.virt_addr +
232 		(masked_head * io_cq->cdesc_entry_size_in_bytes));
233 
234 	/* When the current completion descriptor phase isn't the same as the
235 	 * expected, it mean that the device still didn't update
236 	 * this completion.
237 	 */
238 	cdesc_phase = READ_ONCE16(cdesc->flags) & ENA_ETH_IO_TX_CDESC_PHASE_MASK;
239 	if (cdesc_phase != expected_phase)
240 		return ENA_COM_TRY_AGAIN;
241 
242 	dma_rmb();
243 
244 	*req_id = READ_ONCE16(cdesc->req_id);
245 	if (unlikely(*req_id >= io_cq->q_depth)) {
246 		ena_trc_err("Invalid req id %d\n", cdesc->req_id);
247 		return ENA_COM_INVAL;
248 	}
249 
250 	ena_com_cq_inc_head(io_cq);
251 
252 	return 0;
253 }
254 
255 #if defined(__cplusplus)
256 }
257 #endif
258 #endif /* ENA_ETH_COM_H_ */
259