1 /**********************************************************************
2 * Author: Cavium, Inc.
3 *
4 * Contact: support@cavium.com
5 * Please include "LiquidIO" in the subject.
6 *
7 * Copyright (c) 2003-2016 Cavium, Inc.
8 *
9 * This file is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License, Version 2, as
11 * published by the Free Software Foundation.
12 *
13 * This file is distributed in the hope that it will be useful, but
14 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
15 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
16 * NONINFRINGEMENT. See the GNU General Public License for more details.
17 ***********************************************************************/
18 /*! \file octeon_droq.h
19 * \brief Implementation of Octeon Output queues. "Output" is with
20 * respect to the Octeon device on the NIC. From this driver's point of
21 * view they are ingress queues.
22 */
23
24 #ifndef __OCTEON_DROQ_H__
25 #define __OCTEON_DROQ_H__
26
27 /* Default number of packets that will be processed in one iteration. */
28 #define MAX_PACKET_BUDGET 0xFFFFFFFF
29
30 /** Octeon descriptor format.
31 * The descriptor ring is made of descriptors which have 2 64-bit values:
32 * -# Physical (bus) address of the data buffer.
33 * -# Physical (bus) address of a octeon_droq_info structure.
34 * The Octeon device DMA's incoming packets and its information at the address
35 * given by these descriptor fields.
36 */
37 struct octeon_droq_desc {
38 /** The buffer pointer */
39 u64 buffer_ptr;
40
41 /** The Info pointer */
42 u64 info_ptr;
43 };
44
45 #define OCT_DROQ_DESC_SIZE (sizeof(struct octeon_droq_desc))
46
47 /** Information about packet DMA'ed by Octeon.
48 * The format of the information available at Info Pointer after Octeon
49 * has posted a packet. Not all descriptors have valid information. Only
50 * the Info field of the first descriptor for a packet has information
51 * about the packet.
52 */
53 struct octeon_droq_info {
54 /** The Length of the packet. */
55 u64 length;
56
57 /** The Output Receive Header. */
58 union octeon_rh rh;
59 };
60
61 #define OCT_DROQ_INFO_SIZE (sizeof(struct octeon_droq_info))
62
63 struct octeon_skb_page_info {
64 /* DMA address for the page */
65 dma_addr_t dma;
66
67 /* Page for the rx dma **/
68 struct page *page;
69
70 /** which offset into page */
71 unsigned int page_offset;
72 };
73
74 /** Pointer to data buffer.
75 * Driver keeps a pointer to the data buffer that it made available to
76 * the Octeon device. Since the descriptor ring keeps physical (bus)
77 * addresses, this field is required for the driver to keep track of
78 * the virtual address pointers.
79 */
80 struct octeon_recv_buffer {
81 /** Packet buffer, including metadata. */
82 void *buffer;
83
84 /** Data in the packet buffer. */
85 u8 *data;
86
87 /** pg_info **/
88 struct octeon_skb_page_info pg_info;
89 };
90
91 #define OCT_DROQ_RECVBUF_SIZE (sizeof(struct octeon_recv_buffer))
92
93 /** Output Queue statistics. Each output queue has four stats fields. */
94 struct oct_droq_stats {
95 /** Number of packets received in this queue. */
96 u64 pkts_received;
97
98 /** Bytes received by this queue. */
99 u64 bytes_received;
100
101 /** Packets dropped due to no dispatch function. */
102 u64 dropped_nodispatch;
103
104 /** Packets dropped due to no memory available. */
105 u64 dropped_nomem;
106
107 /** Packets dropped due to large number of pkts to process. */
108 u64 dropped_toomany;
109
110 /** Number of packets sent to stack from this queue. */
111 u64 rx_pkts_received;
112
113 /** Number of Bytes sent to stack from this queue. */
114 u64 rx_bytes_received;
115
116 /** Num of Packets dropped due to receive path failures. */
117 u64 rx_dropped;
118
119 u64 rx_vxlan;
120
121 /** Num of failures of recv_buffer_alloc() */
122 u64 rx_alloc_failure;
123
124 };
125
126 /* The maximum number of buffers that can be dispatched from the
127 * output/dma queue. Set to 64 assuming 1K buffers in DROQ and the fact that
128 * max packet size from DROQ is 64K.
129 */
130 #define MAX_RECV_BUFS 64
131
132 /** Receive Packet format used when dispatching output queue packets
133 * with non-raw opcodes.
134 * The received packet will be sent to the upper layers using this
135 * structure which is passed as a parameter to the dispatch function
136 */
137 struct octeon_recv_pkt {
138 /** Number of buffers in this received packet */
139 u16 buffer_count;
140
141 /** Id of the device that is sending the packet up */
142 u16 octeon_id;
143
144 /** Length of data in the packet buffer */
145 u32 length;
146
147 /** The receive header */
148 union octeon_rh rh;
149
150 /** Pointer to the OS-specific packet buffer */
151 void *buffer_ptr[MAX_RECV_BUFS];
152
153 /** Size of the buffers pointed to by ptr's in buffer_ptr */
154 u32 buffer_size[MAX_RECV_BUFS];
155 };
156
157 #define OCT_RECV_PKT_SIZE (sizeof(struct octeon_recv_pkt))
158
159 /** The first parameter of a dispatch function.
160 * For a raw mode opcode, the driver dispatches with the device
161 * pointer in this structure.
162 * For non-raw mode opcode, the driver dispatches the recv_pkt
163 * created to contain the buffers with data received from Octeon.
164 * ---------------------
165 * | *recv_pkt ----|---
166 * |-------------------| |
167 * | 0 or more bytes | |
168 * | reserved by driver| |
169 * |-------------------|<-/
170 * | octeon_recv_pkt |
171 * | |
172 * |___________________|
173 */
174 struct octeon_recv_info {
175 void *rsvd;
176 struct octeon_recv_pkt *recv_pkt;
177 };
178
179 #define OCT_RECV_INFO_SIZE (sizeof(struct octeon_recv_info))
180
181 /** Allocate a recv_info structure. The recv_pkt pointer in the recv_info
182 * structure is filled in before this call returns.
183 * @param extra_bytes - extra bytes to be allocated at the end of the recv info
184 * structure.
185 * @return - pointer to a newly allocated recv_info structure.
186 */
octeon_alloc_recv_info(int extra_bytes)187 static inline struct octeon_recv_info *octeon_alloc_recv_info(int extra_bytes)
188 {
189 struct octeon_recv_info *recv_info;
190 u8 *buf;
191
192 buf = kmalloc(OCT_RECV_PKT_SIZE + OCT_RECV_INFO_SIZE +
193 extra_bytes, GFP_ATOMIC);
194 if (!buf)
195 return NULL;
196
197 recv_info = (struct octeon_recv_info *)buf;
198 recv_info->recv_pkt =
199 (struct octeon_recv_pkt *)(buf + OCT_RECV_INFO_SIZE);
200 recv_info->rsvd = NULL;
201 if (extra_bytes)
202 recv_info->rsvd = buf + OCT_RECV_INFO_SIZE + OCT_RECV_PKT_SIZE;
203
204 return recv_info;
205 }
206
207 /** Free a recv_info structure.
208 * @param recv_info - Pointer to receive_info to be freed
209 */
octeon_free_recv_info(struct octeon_recv_info * recv_info)210 static inline void octeon_free_recv_info(struct octeon_recv_info *recv_info)
211 {
212 kfree(recv_info);
213 }
214
215 typedef int (*octeon_dispatch_fn_t)(struct octeon_recv_info *, void *);
216
217 /** Used by NIC module to register packet handler and to get device
218 * information for each octeon device.
219 */
220 struct octeon_droq_ops {
221 /** This registered function will be called by the driver with
222 * the octeon id, pointer to buffer from droq and length of
223 * data in the buffer. The receive header gives the port
224 * number to the caller. Function pointer is set by caller.
225 */
226 void (*fptr)(u32, void *, u32, union octeon_rh *, void *, void *);
227 void *farg;
228
229 /* This function will be called by the driver for all NAPI related
230 * events. The first param is the octeon id. The second param is the
231 * output queue number. The third is the NAPI event that occurred.
232 */
233 void (*napi_fn)(void *);
234
235 u32 poll_mode;
236
237 /** Flag indicating if the DROQ handler should drop packets that
238 * it cannot handle in one iteration. Set by caller.
239 */
240 u32 drop_on_max;
241 };
242
243 /** The Descriptor Ring Output Queue structure.
244 * This structure has all the information required to implement a
245 * Octeon DROQ.
246 */
247 struct octeon_droq {
248 /** A spinlock to protect access to this ring. */
249 spinlock_t lock;
250
251 u32 q_no;
252
253 u32 pkt_count;
254
255 struct octeon_droq_ops ops;
256
257 struct octeon_device *oct_dev;
258
259 /** The 8B aligned descriptor ring starts at this address. */
260 struct octeon_droq_desc *desc_ring;
261
262 /** Index in the ring where the driver should read the next packet */
263 u32 read_idx;
264
265 /** Index in the ring where Octeon will write the next packet */
266 u32 write_idx;
267
268 /** Index in the ring where the driver will refill the descriptor's
269 * buffer
270 */
271 u32 refill_idx;
272
273 /** Packets pending to be processed */
274 atomic_t pkts_pending;
275
276 /** Number of descriptors in this ring. */
277 u32 max_count;
278
279 /** The number of descriptors pending refill. */
280 u32 refill_count;
281
282 u32 pkts_per_intr;
283 u32 refill_threshold;
284
285 /** The max number of descriptors in DROQ without a buffer.
286 * This field is used to keep track of empty space threshold. If the
287 * refill_count reaches this value, the DROQ cannot accept a max-sized
288 * (64K) packet.
289 */
290 u32 max_empty_descs;
291
292 /** The receive buffer list. This list has the virtual addresses of the
293 * buffers.
294 */
295 struct octeon_recv_buffer *recv_buf_list;
296
297 /** The size of each buffer pointed by the buffer pointer. */
298 u32 buffer_size;
299
300 /** Pointer to the mapped packet credit register.
301 * Host writes number of info/buffer ptrs available to this register
302 */
303 void __iomem *pkts_credit_reg;
304
305 /** Pointer to the mapped packet sent register.
306 * Octeon writes the number of packets DMA'ed to host memory
307 * in this register.
308 */
309 void __iomem *pkts_sent_reg;
310
311 struct list_head dispatch_list;
312
313 /** Statistics for this DROQ. */
314 struct oct_droq_stats stats;
315
316 /** DMA mapped address of the DROQ descriptor ring. */
317 size_t desc_ring_dma;
318
319 /** application context */
320 void *app_ctx;
321
322 struct napi_struct napi;
323
324 u32 cpu_id;
325
326 call_single_data_t csd;
327 };
328
329 #define OCT_DROQ_SIZE (sizeof(struct octeon_droq))
330
331 /**
332 * Allocates space for the descriptor ring for the droq and sets the
333 * base addr, num desc etc in Octeon registers.
334 *
335 * @param oct_dev - pointer to the octeon device structure
336 * @param q_no - droq no. ranges from 0 - 3.
337 * @param app_ctx - pointer to application context
338 * @return Success: 0 Failure: 1
339 */
340 int octeon_init_droq(struct octeon_device *oct_dev,
341 u32 q_no,
342 u32 num_descs,
343 u32 desc_size,
344 void *app_ctx);
345
346 /**
347 * Frees the space for descriptor ring for the droq.
348 *
349 * @param oct_dev - pointer to the octeon device structure
350 * @param q_no - droq no. ranges from 0 - 3.
351 * @return: Success: 0 Failure: 1
352 */
353 int octeon_delete_droq(struct octeon_device *oct_dev, u32 q_no);
354
355 /** Register a change in droq operations. The ops field has a pointer to a
356 * function which will called by the DROQ handler for all packets arriving
357 * on output queues given by q_no irrespective of the type of packet.
358 * The ops field also has a flag which if set tells the DROQ handler to
359 * drop packets if it receives more than what it can process in one
360 * invocation of the handler.
361 * @param oct - octeon device
362 * @param q_no - octeon output queue number (0 <= q_no <= MAX_OCTEON_DROQ-1
363 * @param ops - the droq_ops settings for this queue
364 * @return - 0 on success, -ENODEV or -EINVAL on error.
365 */
366 int
367 octeon_register_droq_ops(struct octeon_device *oct,
368 u32 q_no,
369 struct octeon_droq_ops *ops);
370
371 /** Resets the function pointer and flag settings made by
372 * octeon_register_droq_ops(). After this routine is called, the DROQ handler
373 * will lookup dispatch function for each arriving packet on the output queue
374 * given by q_no.
375 * @param oct - octeon device
376 * @param q_no - octeon output queue number (0 <= q_no <= MAX_OCTEON_DROQ-1
377 * @return - 0 on success, -ENODEV or -EINVAL on error.
378 */
379 int octeon_unregister_droq_ops(struct octeon_device *oct, u32 q_no);
380
381 /** Register a dispatch function for a opcode/subcode. The driver will call
382 * this dispatch function when it receives a packet with the given
383 * opcode/subcode in its output queues along with the user specified
384 * argument.
385 * @param oct - the octeon device to register with.
386 * @param opcode - the opcode for which the dispatch will be registered.
387 * @param subcode - the subcode for which the dispatch will be registered
388 * @param fn - the dispatch function.
389 * @param fn_arg - user specified that will be passed along with the
390 * dispatch function by the driver.
391 * @return Success: 0; Failure: 1
392 */
393 int octeon_register_dispatch_fn(struct octeon_device *oct,
394 u16 opcode,
395 u16 subcode,
396 octeon_dispatch_fn_t fn, void *fn_arg);
397
398 void *octeon_get_dispatch_arg(struct octeon_device *oct,
399 u16 opcode, u16 subcode);
400
401 void octeon_droq_print_stats(void);
402
403 u32 octeon_droq_check_hw_for_pkts(struct octeon_droq *droq);
404
405 int octeon_create_droq(struct octeon_device *oct, u32 q_no,
406 u32 num_descs, u32 desc_size, void *app_ctx);
407
408 int octeon_droq_process_packets(struct octeon_device *oct,
409 struct octeon_droq *droq,
410 u32 budget);
411
412 int octeon_droq_process_poll_pkts(struct octeon_device *oct,
413 struct octeon_droq *droq, u32 budget);
414
415 int octeon_enable_irq(struct octeon_device *oct, u32 q_no);
416
417 void octeon_droq_check_oom(struct octeon_droq *droq);
418
419 #endif /*__OCTEON_DROQ_H__ */
420
