linux/drivers/net/ethernet/cavium/liquidio/octeon_droq.h
<<
>>
Prefs
   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 */
  37struct 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 */
  53struct 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
  63struct 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 */
  80struct 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. */
  94struct 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 */
 137struct 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 */
 174struct 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 */
 187static 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 */
 210static inline void octeon_free_recv_info(struct octeon_recv_info *recv_info)
 211{
 212        kfree(recv_info);
 213}
 214
 215typedef 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 */
 220struct 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 */
 247struct 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        struct call_single_data 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 */
 340int 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 */
 353int 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 */
 366int
 367octeon_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 */
 379int 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 */
 393int octeon_register_dispatch_fn(struct octeon_device *oct,
 394                                u16 opcode,
 395                                u16 subcode,
 396                                octeon_dispatch_fn_t fn, void *fn_arg);
 397
 398void *octeon_get_dispatch_arg(struct octeon_device *oct,
 399                              u16 opcode, u16 subcode);
 400
 401void octeon_droq_print_stats(void);
 402
 403u32 octeon_droq_check_hw_for_pkts(struct octeon_droq *droq);
 404
 405int octeon_create_droq(struct octeon_device *oct, u32 q_no,
 406                       u32 num_descs, u32 desc_size, void *app_ctx);
 407
 408int octeon_droq_process_packets(struct octeon_device *oct,
 409                                struct octeon_droq *droq,
 410                                u32 budget);
 411
 412int octeon_droq_process_poll_pkts(struct octeon_device *oct,
 413                                  struct octeon_droq *droq, u32 budget);
 414
 415int octeon_enable_irq(struct octeon_device *oct, u32 q_no);
 416
 417void octeon_droq_check_oom(struct octeon_droq *droq);
 418
 419#endif  /*__OCTEON_DROQ_H__ */
 420