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) 2003-2015 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
  17  * details.
  18  *
  19  * This file may also be available under a different license from Cavium.
  20  * Contact Cavium, Inc. for more information
  21  **********************************************************************/
  22
  23 /*!  \file  octeon_droq.h
  24  *   \brief Implementation of Octeon Output queues. "Output" is with
  25  *   respect to the Octeon device on the NIC. From this driver's point of
  26  *   view they are ingress queues.
  27  */
  28
  29 #ifndef __OCTEON_DROQ_H__
  30 #define __OCTEON_DROQ_H__
  31
  32 /* Default number of packets that will be processed in one iteration. */
  33 #define MAX_PACKET_BUDGET 0xFFFFFFFF
  34
  35 /** Octeon descriptor format.
  36  *  The descriptor ring is made of descriptors which have 2 64-bit values:
  37  *  -# Physical (bus) address of the data buffer.
  38  *  -# Physical (bus) address of a octeon_droq_info structure.
  39  *  The Octeon device DMA's incoming packets and its information at the address
  40  *  given by these descriptor fields.
  41  */
  42 struct octeon_droq_desc {
  43         /** The buffer pointer */
  44         u64 buffer_ptr;
  45
  46         /** The Info pointer */
  47         u64 info_ptr;
  48 };
  49
  50 #define OCT_DROQ_DESC_SIZE    (sizeof(struct octeon_droq_desc))
  51
  52 /** Information about packet DMA'ed by Octeon.
  53  *  The format of the information available at Info Pointer after Octeon
  54  *  has posted a packet. Not all descriptors have valid information. Only
  55  *  the Info field of the first descriptor for a packet has information
  56  *  about the packet.
  57  */
  58 struct octeon_droq_info {
  59         /** The Output Receive Header. */
  60         union octeon_rh rh;
  61
  62         /** The Length of the packet. */
  63         u64 length;
  64 };
  65
  66 #define OCT_DROQ_INFO_SIZE   (sizeof(struct octeon_droq_info))
  67
  68 struct octeon_skb_page_info {
  69         /* DMA address for the page */
  70         dma_addr_t dma;
  71
  72         /* Page for the rx dma  **/
  73         struct page *page;
  74
  75         /** which offset into page */
  76         unsigned int page_offset;
  77 };
  78
  79 /** Pointer to data buffer.
  80  *  Driver keeps a pointer to the data buffer that it made available to
  81  *  the Octeon device. Since the descriptor ring keeps physical (bus)
  82  *  addresses, this field is required for the driver to keep track of
  83  *  the virtual address pointers.
  84 */
  85 struct octeon_recv_buffer {
  86         /** Packet buffer, including metadata. */
  87         void *buffer;
  88
  89         /** Data in the packet buffer.  */
  90         u8 *data;
  91
  92         /** pg_info **/
  93         struct octeon_skb_page_info pg_info;
  94 };
  95
  96 #define OCT_DROQ_RECVBUF_SIZE    (sizeof(struct octeon_recv_buffer))
  97
  98 /** Output Queue statistics. Each output queue has four stats fields. */
  99 struct oct_droq_stats {
 100         /** Number of packets received in this queue. */
 101         u64 pkts_received;
 102
 103         /** Bytes received by this queue. */
 104         u64 bytes_received;
 105
 106         /** Packets dropped due to no dispatch function. */
 107         u64 dropped_nodispatch;
 108
 109         /** Packets dropped due to no memory available. */
 110         u64 dropped_nomem;
 111
 112         /** Packets dropped due to large number of pkts to process. */
 113         u64 dropped_toomany;
 114
 115         /** Number of packets  sent to stack from this queue. */
 116         u64 rx_pkts_received;
 117
 118         /** Number of Bytes sent to stack from this queue. */
 119         u64 rx_bytes_received;
 120
 121         /** Num of Packets dropped due to receive path failures. */
 122         u64 rx_dropped;
 123
 124         /** Num of vxlan packets received; */
 125         u64 rx_vxlan;
 126
 127         /** Num of failures of recv_buffer_alloc() */
 128         u64 rx_alloc_failure;
 129
 130 };
 131
 132 #define POLL_EVENT_INTR_ARRIVED  1
 133 #define POLL_EVENT_PROCESS_PKTS  2
 134 #define POLL_EVENT_PENDING_PKTS  3
 135 #define POLL_EVENT_ENABLE_INTR   4
 136
 137 /* The maximum number of buffers that can be dispatched from the
 138  * output/dma queue. Set to 64 assuming 1K buffers in DROQ and the fact that
 139  * max packet size from DROQ is 64K.
 140  */
 141 #define    MAX_RECV_BUFS    64
 142
 143 /** Receive Packet format used when dispatching output queue packets
 144  *  with non-raw opcodes.
 145  *  The received packet will be sent to the upper layers using this
 146  *  structure which is passed as a parameter to the dispatch function
 147  */
 148 struct octeon_recv_pkt {
 149         /**  Number of buffers in this received packet */
 150         u16 buffer_count;
 151
 152         /** Id of the device that is sending the packet up */
 153         u16 octeon_id;
 154
 155         /** Length of data in the packet buffer */
 156         u32 length;
 157
 158         /** The receive header */
 159         union octeon_rh rh;
 160
 161         /** Pointer to the OS-specific packet buffer */
 162         void *buffer_ptr[MAX_RECV_BUFS];
 163
 164         /** Size of the buffers pointed to by ptr's in buffer_ptr */
 165         u32 buffer_size[MAX_RECV_BUFS];
 166 };
 167
 168 #define OCT_RECV_PKT_SIZE    (sizeof(struct octeon_recv_pkt))
 169
 170 /** The first parameter of a dispatch function.
 171  *  For a raw mode opcode, the driver dispatches with the device
 172  *  pointer in this structure.
 173  *  For non-raw mode opcode, the driver dispatches the recv_pkt
 174  *  created to contain the buffers with data received from Octeon.
 175  *  ---------------------
 176  *  |     *recv_pkt ----|---
 177  *  |-------------------|   |
 178  *  | 0 or more bytes   |   |
 179  *  | reserved by driver|   |
 180  *  |-------------------|<-/
 181  *  | octeon_recv_pkt   |
 182  *  |                   |
 183  *  |___________________|
 184  */
 185 struct octeon_recv_info {
 186         void *rsvd;
 187         struct octeon_recv_pkt *recv_pkt;
 188 };
 189
 190 #define  OCT_RECV_INFO_SIZE    (sizeof(struct octeon_recv_info))
 191
 192 /** Allocate a recv_info structure. The recv_pkt pointer in the recv_info
 193  *  structure is filled in before this call returns.
 194  *  @param extra_bytes - extra bytes to be allocated at the end of the recv info
 195  *                       structure.
 196  *  @return - pointer to a newly allocated recv_info structure.
 197  */
 198 static inline struct octeon_recv_info *octeon_alloc_recv_info(int extra_bytes)
 199 {
 200         struct octeon_recv_info *recv_info;
 201         u8 *buf;
 202
 203         buf = kmalloc(OCT_RECV_PKT_SIZE + OCT_RECV_INFO_SIZE +
 204                       extra_bytes, GFP_ATOMIC);
 205         if (!buf)
 206                 return NULL;
 207
 208         recv_info = (struct octeon_recv_info *)buf;
 209         recv_info->recv_pkt =
 210                 (struct octeon_recv_pkt *)(buf + OCT_RECV_INFO_SIZE);
 211         recv_info->rsvd = NULL;
 212         if (extra_bytes)
 213                 recv_info->rsvd = buf + OCT_RECV_INFO_SIZE + OCT_RECV_PKT_SIZE;
 214
 215         return recv_info;
 216 }
 217
 218 /** Free a recv_info structure.
 219  *  @param recv_info - Pointer to receive_info to be freed
 220  */
 221 static inline void octeon_free_recv_info(struct octeon_recv_info *recv_info)
 222 {
 223         kfree(recv_info);
 224 }
 225
 226 typedef int (*octeon_dispatch_fn_t)(struct octeon_recv_info *, void *);
 227
 228 /** Used by NIC module to register packet handler and to get device
 229  * information for each octeon device.
 230  */
 231 struct octeon_droq_ops {
 232         /** This registered function will be called by the driver with
 233          *  the octeon id, pointer to buffer from droq and length of
 234          *  data in the buffer. The receive header gives the port
 235          *  number to the caller.  Function pointer is set by caller.
 236          */
 237         void (*fptr)(u32, void *, u32, union octeon_rh *, void *, void *);
 238         void *farg;
 239
 240         /* This function will be called by the driver for all NAPI related
 241          * events. The first param is the octeon id. The second param is the
 242          * output queue number. The third is the NAPI event that occurred.
 243          */
 244         void (*napi_fn)(void *);
 245
 246         u32 poll_mode;
 247
 248         /** Flag indicating if the DROQ handler should drop packets that
 249          *  it cannot handle in one iteration. Set by caller.
 250          */
 251         u32 drop_on_max;
 252 };
 253
 254 /** The Descriptor Ring Output Queue structure.
 255  *  This structure has all the information required to implement a
 256  *  Octeon DROQ.
 257  */
 258 struct octeon_droq {
 259         /** A spinlock to protect access to this ring. */
 260         spinlock_t lock;
 261
 262         u32 q_no;
 263
 264         struct octeon_droq_ops ops;
 265
 266         struct octeon_device *oct_dev;
 267
 268         /** The 8B aligned descriptor ring starts at this address. */
 269         struct octeon_droq_desc *desc_ring;
 270
 271         /** Index in the ring where the driver should read the next packet */
 272         u32 read_idx;
 273
 274         /** Index in the ring where Octeon will write the next packet */
 275         u32 write_idx;
 276
 277         /** Index in the ring where the driver will refill the descriptor's
 278          * buffer
 279          */
 280         u32 refill_idx;
 281
 282         /** Packets pending to be processed */
 283         atomic_t pkts_pending;
 284
 285         /** Number of  descriptors in this ring. */
 286         u32 max_count;
 287
 288         /** The number of descriptors pending refill. */
 289         u32 refill_count;
 290
 291         u32 pkts_per_intr;
 292         u32 refill_threshold;
 293
 294         /** The max number of descriptors in DROQ without a buffer.
 295          * This field is used to keep track of empty space threshold. If the
 296          * refill_count reaches this value, the DROQ cannot accept a max-sized
 297          * (64K) packet.
 298          */
 299         u32 max_empty_descs;
 300
 301         /** The 8B aligned info ptrs begin from this address. */
 302         struct octeon_droq_info *info_list;
 303
 304         /** The receive buffer list. This list has the virtual addresses of the
 305          * buffers.
 306          */
 307         struct octeon_recv_buffer *recv_buf_list;
 308
 309         /** The size of each buffer pointed by the buffer pointer. */
 310         u32 buffer_size;
 311
 312         /** Pointer to the mapped packet credit register.
 313          * Host writes number of info/buffer ptrs available to this register
 314          */
 315         void  __iomem *pkts_credit_reg;
 316
 317         /** Pointer to the mapped packet sent register.
 318          * Octeon writes the number of packets DMA'ed to host memory
 319          * in this register.
 320          */
 321         void __iomem *pkts_sent_reg;
 322
 323         struct list_head dispatch_list;
 324
 325         /** Statistics for this DROQ. */
 326         struct oct_droq_stats stats;
 327
 328         /** DMA mapped address of the DROQ descriptor ring. */
 329         size_t desc_ring_dma;
 330
 331         /** Info ptr list are allocated at this virtual address. */
 332         size_t info_base_addr;
 333
 334         /** DMA mapped address of the info list */
 335         size_t info_list_dma;
 336
 337         /** Allocated size of info list. */
 338         u32 info_alloc_size;
 339
 340         /** application context */
 341         void *app_ctx;
 342
 343         struct napi_struct napi;
 344
 345         u32 cpu_id;
 346
 347         struct call_single_data csd;
 348 };
 349
 350 #define OCT_DROQ_SIZE   (sizeof(struct octeon_droq))
 351
 352 /**
 353  *  Allocates space for the descriptor ring for the droq and sets the
 354  *   base addr, num desc etc in Octeon registers.
 355  *
 356  * @param  oct_dev    - pointer to the octeon device structure
 357  * @param  q_no       - droq no. ranges from 0 - 3.
 358  * @param app_ctx     - pointer to application context
 359  * @return Success: 0    Failure: 1
 360 */
 361 int octeon_init_droq(struct octeon_device *oct_dev,
 362                      u32 q_no,
 363                      u32 num_descs,
 364                      u32 desc_size,
 365                      void *app_ctx);
 366
 367 /**
 368  *  Frees the space for descriptor ring for the droq.
 369  *
 370  *  @param oct_dev - pointer to the octeon device structure
 371  *  @param q_no    - droq no. ranges from 0 - 3.
 372  *  @return:    Success: 0    Failure: 1
 373 */
 374 int octeon_delete_droq(struct octeon_device *oct_dev, u32 q_no);
 375
 376 /** Register a change in droq operations. The ops field has a pointer to a
 377  * function which will called by the DROQ handler for all packets arriving
 378  * on output queues given by q_no irrespective of the type of packet.
 379  * The ops field also has a flag which if set tells the DROQ handler to
 380  * drop packets if it receives more than what it can process in one
 381  * invocation of the handler.
 382  * @param oct       - octeon device
 383  * @param q_no      - octeon output queue number (0 <= q_no <= MAX_OCTEON_DROQ-1
 384  * @param ops       - the droq_ops settings for this queue
 385  * @return          - 0 on success, -ENODEV or -EINVAL on error.
 386  */
 387 int
 388 octeon_register_droq_ops(struct octeon_device *oct,
 389                          u32 q_no,
 390                          struct octeon_droq_ops *ops);
 391
 392 /** Resets the function pointer and flag settings made by
 393  * octeon_register_droq_ops(). After this routine is called, the DROQ handler
 394  * will lookup dispatch function for each arriving packet on the output queue
 395  * given by q_no.
 396  * @param oct       - octeon device
 397  * @param q_no      - octeon output queue number (0 <= q_no <= MAX_OCTEON_DROQ-1
 398  * @return          - 0 on success, -ENODEV or -EINVAL on error.
 399  */
 400 int octeon_unregister_droq_ops(struct octeon_device *oct, u32 q_no);
 401
 402 /**   Register a dispatch function for a opcode/subcode. The driver will call
 403  *    this dispatch function when it receives a packet with the given
 404  *    opcode/subcode in its output queues along with the user specified
 405  *    argument.
 406  *    @param  oct        - the octeon device to register with.
 407  *    @param  opcode     - the opcode for which the dispatch will be registered.
 408  *    @param  subcode    - the subcode for which the dispatch will be registered
 409  *    @param  fn         - the dispatch function.
 410  *    @param  fn_arg     - user specified that will be passed along with the
 411  *                         dispatch function by the driver.
 412  *    @return Success: 0; Failure: 1
 413  */
 414 int octeon_register_dispatch_fn(struct octeon_device *oct,
 415                                 u16 opcode,
 416                                 u16 subcode,
 417                                 octeon_dispatch_fn_t fn, void *fn_arg);
 418
 419 void octeon_droq_print_stats(void);
 420
 421 u32 octeon_droq_check_hw_for_pkts(struct octeon_droq *droq);
 422
 423 int octeon_create_droq(struct octeon_device *oct, u32 q_no,
 424                        u32 num_descs, u32 desc_size, void *app_ctx);
 425
 426 int octeon_droq_process_packets(struct octeon_device *oct,
 427                                 struct octeon_droq *droq,
 428                                 u32 budget);
 429
 430 int octeon_process_droq_poll_cmd(struct octeon_device *oct, u32 q_no,
 431                                  int cmd, u32 arg);
 432
 433 #endif  /*__OCTEON_DROQ_H__ */