drivers/net/ethernet/cavium/liquidio/octeon_droq.h

   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 Output Receive Header. */
  55         union octeon_rh rh;
  56
  57         /** The Length of the packet. */
  58         u64 length;
  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 #define POLL_EVENT_INTR_ARRIVED  1
 127 #define POLL_EVENT_PROCESS_PKTS  2
 128 #define POLL_EVENT_PENDING_PKTS  3
 129 #define POLL_EVENT_ENABLE_INTR   4
 130
 131 /* The maximum number of buffers that can be dispatched from the
 132  * output/dma queue. Set to 64 assuming 1K buffers in DROQ and the fact that
 133  * max packet size from DROQ is 64K.
 134  */
 135 #define    MAX_RECV_BUFS    64
 136
 137 /** Receive Packet format used when dispatching output queue packets
 138  *  with non-raw opcodes.
 139  *  The received packet will be sent to the upper layers using this
 140  *  structure which is passed as a parameter to the dispatch function
 141  */
 142 struct octeon_recv_pkt {
 143         /**  Number of buffers in this received packet */
 144         u16 buffer_count;
 145
 146         /** Id of the device that is sending the packet up */
 147         u16 octeon_id;
 148
 149         /** Length of data in the packet buffer */
 150         u32 length;
 151
 152         /** The receive header */
 153         union octeon_rh rh;
 154
 155         /** Pointer to the OS-specific packet buffer */
 156         void *buffer_ptr[MAX_RECV_BUFS];
 157
 158         /** Size of the buffers pointed to by ptr's in buffer_ptr */
 159         u32 buffer_size[MAX_RECV_BUFS];
 160 };
 161
 162 #define OCT_RECV_PKT_SIZE    (sizeof(struct octeon_recv_pkt))
 163
 164 /** The first parameter of a dispatch function.
 165  *  For a raw mode opcode, the driver dispatches with the device
 166  *  pointer in this structure.
 167  *  For non-raw mode opcode, the driver dispatches the recv_pkt
 168  *  created to contain the buffers with data received from Octeon.
 169  *  ---------------------
 170  *  |     *recv_pkt ----|---
 171  *  |-------------------|   |
 172  *  | 0 or more bytes   |   |
 173  *  | reserved by driver|   |
 174  *  |-------------------|<-/
 175  *  | octeon_recv_pkt   |
 176  *  |                   |
 177  *  |___________________|
 178  */
 179 struct octeon_recv_info {
 180         void *rsvd;
 181         struct octeon_recv_pkt *recv_pkt;
 182 };
 183
 184 #define  OCT_RECV_INFO_SIZE    (sizeof(struct octeon_recv_info))
 185
 186 /** Allocate a recv_info structure. The recv_pkt pointer in the recv_info
 187  *  structure is filled in before this call returns.
 188  *  @param extra_bytes - extra bytes to be allocated at the end of the recv info
 189  *                       structure.
 190  *  @return - pointer to a newly allocated recv_info structure.
 191  */
 192 static inline struct octeon_recv_info *octeon_alloc_recv_info(int extra_bytes)
 193 {
 194         struct octeon_recv_info *recv_info;
 195         u8 *buf;
 196
 197         buf = kmalloc(OCT_RECV_PKT_SIZE + OCT_RECV_INFO_SIZE +
 198                       extra_bytes, GFP_ATOMIC);
 199         if (!buf)
 200                 return NULL;
 201
 202         recv_info = (struct octeon_recv_info *)buf;
 203         recv_info->recv_pkt =
 204                 (struct octeon_recv_pkt *)(buf + OCT_RECV_INFO_SIZE);
 205         recv_info->rsvd = NULL;
 206         if (extra_bytes)
 207                 recv_info->rsvd = buf + OCT_RECV_INFO_SIZE + OCT_RECV_PKT_SIZE;
 208
 209         return recv_info;
 210 }
 211
 212 /** Free a recv_info structure.
 213  *  @param recv_info - Pointer to receive_info to be freed
 214  */
 215 static inline void octeon_free_recv_info(struct octeon_recv_info *recv_info)
 216 {
 217         kfree(recv_info);
 218 }
 219
 220 typedef int (*octeon_dispatch_fn_t)(struct octeon_recv_info *, void *);
 221
 222 /** Used by NIC module to register packet handler and to get device
 223  * information for each octeon device.
 224  */
 225 struct octeon_droq_ops {
 226         /** This registered function will be called by the driver with
 227          *  the octeon id, pointer to buffer from droq and length of
 228          *  data in the buffer. The receive header gives the port
 229          *  number to the caller.  Function pointer is set by caller.
 230          */
 231         void (*fptr)(u32, void *, u32, union octeon_rh *, void *, void *);
 232         void *farg;
 233
 234         /* This function will be called by the driver for all NAPI related
 235          * events. The first param is the octeon id. The second param is the
 236          * output queue number. The third is the NAPI event that occurred.
 237          */
 238         void (*napi_fn)(void *);
 239
 240         u32 poll_mode;
 241
 242         /** Flag indicating if the DROQ handler should drop packets that
 243          *  it cannot handle in one iteration. Set by caller.
 244          */
 245         u32 drop_on_max;
 246 };
 247
 248 /** The Descriptor Ring Output Queue structure.
 249  *  This structure has all the information required to implement a
 250  *  Octeon DROQ.
 251  */
 252 struct octeon_droq {
 253         /** A spinlock to protect access to this ring. */
 254         spinlock_t lock;
 255
 256         u32 q_no;
 257
 258         u32 pkt_count;
 259
 260         struct octeon_droq_ops ops;
 261
 262         struct octeon_device *oct_dev;
 263
 264         /** The 8B aligned descriptor ring starts at this address. */
 265         struct octeon_droq_desc *desc_ring;
 266
 267         /** Index in the ring where the driver should read the next packet */
 268         u32 read_idx;
 269
 270         /** Index in the ring where Octeon will write the next packet */
 271         u32 write_idx;
 272
 273         /** Index in the ring where the driver will refill the descriptor's
 274          * buffer
 275          */
 276         u32 refill_idx;
 277
 278         /** Packets pending to be processed */
 279         atomic_t pkts_pending;
 280
 281         /** Number of  descriptors in this ring. */
 282         u32 max_count;
 283
 284         /** The number of descriptors pending refill. */
 285         u32 refill_count;
 286
 287         u32 pkts_per_intr;
 288         u32 refill_threshold;
 289
 290         /** The max number of descriptors in DROQ without a buffer.
 291          * This field is used to keep track of empty space threshold. If the
 292          * refill_count reaches this value, the DROQ cannot accept a max-sized
 293          * (64K) packet.
 294          */
 295         u32 max_empty_descs;
 296
 297         /** The 8B aligned info ptrs begin from this address. */
 298         struct octeon_droq_info *info_list;
 299
 300         /** The receive buffer list. This list has the virtual addresses of the
 301          * buffers.
 302          */
 303         struct octeon_recv_buffer *recv_buf_list;
 304
 305         /** The size of each buffer pointed by the buffer pointer. */
 306         u32 buffer_size;
 307
 308         /** Pointer to the mapped packet credit register.
 309          * Host writes number of info/buffer ptrs available to this register
 310          */
 311         void  __iomem *pkts_credit_reg;
 312
 313         /** Pointer to the mapped packet sent register.
 314          * Octeon writes the number of packets DMA'ed to host memory
 315          * in this register.
 316          */
 317         void __iomem *pkts_sent_reg;
 318
 319         struct list_head dispatch_list;
 320
 321         /** Statistics for this DROQ. */
 322         struct oct_droq_stats stats;
 323
 324         /** DMA mapped address of the DROQ descriptor ring. */
 325         size_t desc_ring_dma;
 326
 327         /** Info ptr list are allocated at this virtual address. */
 328         void *info_base_addr;
 329
 330         /** DMA mapped address of the info list */
 331         dma_addr_t info_list_dma;
 332
 333         /** Allocated size of info list. */
 334         u32 info_alloc_size;
 335
 336         /** application context */
 337         void *app_ctx;
 338
 339         struct napi_struct napi;
 340
 341         u32 cpu_id;
 342
 343         struct call_single_data csd;
 344 };
 345
 346 #define OCT_DROQ_SIZE   (sizeof(struct octeon_droq))
 347
 348 /**
 349  *  Allocates space for the descriptor ring for the droq and sets the
 350  *   base addr, num desc etc in Octeon registers.
 351  *
 352  * @param  oct_dev    - pointer to the octeon device structure
 353  * @param  q_no       - droq no. ranges from 0 - 3.
 354  * @param app_ctx     - pointer to application context
 355  * @return Success: 0    Failure: 1
 356  */
 357 int octeon_init_droq(struct octeon_device *oct_dev,
 358                      u32 q_no,
 359                      u32 num_descs,
 360                      u32 desc_size,
 361                      void *app_ctx);
 362
 363 /**
 364  *  Frees the space for descriptor ring for the droq.
 365  *
 366  *  @param oct_dev - pointer to the octeon device structure
 367  *  @param q_no    - droq no. ranges from 0 - 3.
 368  *  @return:    Success: 0    Failure: 1
 369  */
 370 int octeon_delete_droq(struct octeon_device *oct_dev, u32 q_no);
 371
 372 /** Register a change in droq operations. The ops field has a pointer to a
 373  * function which will called by the DROQ handler for all packets arriving
 374  * on output queues given by q_no irrespective of the type of packet.
 375  * The ops field also has a flag which if set tells the DROQ handler to
 376  * drop packets if it receives more than what it can process in one
 377  * invocation of the handler.
 378  * @param oct       - octeon device
 379  * @param q_no      - octeon output queue number (0 <= q_no <= MAX_OCTEON_DROQ-1
 380  * @param ops       - the droq_ops settings for this queue
 381  * @return          - 0 on success, -ENODEV or -EINVAL on error.
 382  */
 383 int
 384 octeon_register_droq_ops(struct octeon_device *oct,
 385                          u32 q_no,
 386                          struct octeon_droq_ops *ops);
 387
 388 /** Resets the function pointer and flag settings made by
 389  * octeon_register_droq_ops(). After this routine is called, the DROQ handler
 390  * will lookup dispatch function for each arriving packet on the output queue
 391  * given by q_no.
 392  * @param oct       - octeon device
 393  * @param q_no      - octeon output queue number (0 <= q_no <= MAX_OCTEON_DROQ-1
 394  * @return          - 0 on success, -ENODEV or -EINVAL on error.
 395  */
 396 int octeon_unregister_droq_ops(struct octeon_device *oct, u32 q_no);
 397
 398 /**   Register a dispatch function for a opcode/subcode. The driver will call
 399  *    this dispatch function when it receives a packet with the given
 400  *    opcode/subcode in its output queues along with the user specified
 401  *    argument.
 402  *    @param  oct        - the octeon device to register with.
 403  *    @param  opcode     - the opcode for which the dispatch will be registered.
 404  *    @param  subcode    - the subcode for which the dispatch will be registered
 405  *    @param  fn         - the dispatch function.
 406  *    @param  fn_arg     - user specified that will be passed along with the
 407  *                         dispatch function by the driver.
 408  *    @return Success: 0; Failure: 1
 409  */
 410 int octeon_register_dispatch_fn(struct octeon_device *oct,
 411                                 u16 opcode,
 412                                 u16 subcode,
 413                                 octeon_dispatch_fn_t fn, void *fn_arg);
 414
 415 void octeon_droq_print_stats(void);
 416
 417 u32 octeon_droq_check_hw_for_pkts(struct octeon_droq *droq);
 418
 419 int octeon_create_droq(struct octeon_device *oct, u32 q_no,
 420                        u32 num_descs, u32 desc_size, void *app_ctx);
 421
 422 int octeon_droq_process_packets(struct octeon_device *oct,
 423                                 struct octeon_droq *droq,
 424                                 u32 budget);
 425
 426 int octeon_process_droq_poll_cmd(struct octeon_device *oct, u32 q_no,
 427                                  int cmd, u32 arg);
 428
 429 #endif  /*__OCTEON_DROQ_H__ */