LXR linux/drivers/net/ethernet/chelsio/libcxgb/libcxgb

   1/*
   2 * libcxgb_ppm.h: Chelsio common library for T3/T4/T5 iSCSI ddp operation
   3 *
   4 * Copyright (c) 2016 Chelsio Communications, Inc. All rights reserved.
   5 *
   6 * This software is available to you under a choice of one of two
   7 * licenses.  You may choose to be licensed under the terms of the GNU
   8 * General Public License (GPL) Version 2, available from the file
   9 * COPYING in the main directory of this source tree, or the
  10 * OpenIB.org BSD license below:
  11 *
  12 *     Redistribution and use in source and binary forms, with or
  13 *     without modification, are permitted provided that the following
  14 *     conditions are met:
  15 *
  16 *      - Redistributions of source code must retain the above
  17 *        copyright notice, this list of conditions and the following
  18 *        disclaimer.
  19 *
  20 *      - Redistributions in binary form must reproduce the above
  21 *        copyright notice, this list of conditions and the following
  22 *        disclaimer in the documentation and/or other materials
  23 *        provided with the distribution.
  24 *
  25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32 * SOFTWARE.
  33 *
  34 * Written by: Karen Xie (kxie@chelsio.com)
  35 */
  36
  37#ifndef __LIBCXGB_PPM_H__
  38#define __LIBCXGB_PPM_H__
  39
  40#include <linux/kernel.h>
  41#include <linux/errno.h>
  42#include <linux/types.h>
  43#include <linux/debugfs.h>
  44#include <linux/list.h>
  45#include <linux/netdevice.h>
  46#include <linux/scatterlist.h>
  47#include <linux/skbuff.h>
  48#include <linux/vmalloc.h>
  49#include <linux/bitmap.h>
  50
  51struct cxgbi_pagepod_hdr {
  52        u32 vld_tid;
  53        u32 pgsz_tag_clr;
  54        u32 max_offset;
  55        u32 page_offset;
  56        u64 rsvd;
  57};
  58
  59#define PPOD_PAGES_MAX                  4
  60struct cxgbi_pagepod {
  61        struct cxgbi_pagepod_hdr hdr;
  62        u64 addr[PPOD_PAGES_MAX + 1];
  63};
  64
  65/* ddp tag format
  66 * for a 32-bit tag:
  67 * bit #
  68 * 31 .....   .....  0
  69 *     X   Y...Y Z...Z, where
  70 *     ^   ^^^^^ ^^^^
  71 *     |   |      |____ when ddp bit = 0: color bits
  72 *     |   |
  73 *     |   |____ when ddp bit = 0: idx into the ddp memory region
  74 *     |
  75 *     |____ ddp bit: 0 - ddp tag, 1 - non-ddp tag
  76 *
  77 *  [page selector:2] [sw/free bits] [0] [idx] [color:6]
  78 */
  79
  80#define DDP_PGIDX_MAX           4
  81#define DDP_PGSZ_BASE_SHIFT     12      /* base page 4K */
  82
  83struct cxgbi_task_tag_info {
  84        unsigned char flags;
  85#define CXGBI_PPOD_INFO_FLAG_VALID      0x1
  86#define CXGBI_PPOD_INFO_FLAG_MAPPED     0x2
  87        unsigned char cid;
  88        unsigned short pg_shift;
  89        unsigned int npods;
  90        unsigned int idx;
  91        unsigned int tag;
  92        struct cxgbi_pagepod_hdr hdr;
  93        int nents;
  94        int nr_pages;
  95        struct scatterlist *sgl;
  96};
  97
  98struct cxgbi_tag_format {
  99        unsigned char pgsz_order[DDP_PGIDX_MAX];
 100        unsigned char pgsz_idx_dflt;
 101        unsigned char free_bits:4;
 102        unsigned char color_bits:4;
 103        unsigned char idx_bits;
 104        unsigned char rsvd_bits;
 105        unsigned int  no_ddp_mask;
 106        unsigned int  idx_mask;
 107        unsigned int  color_mask;
 108        unsigned int  idx_clr_mask;
 109        unsigned int  rsvd_mask;
 110};
 111
 112struct cxgbi_ppod_data {
 113        unsigned char pg_idx:2;
 114        unsigned char color:6;
 115        unsigned char chan_id;
 116        unsigned short npods;
 117        unsigned long caller_data;
 118};
 119
 120/* per cpu ppm pool */
 121struct cxgbi_ppm_pool {
 122        unsigned int base;              /* base index */
 123        unsigned int next;              /* next possible free index */
 124        spinlock_t lock;                /* ppm pool lock */
 125        unsigned long bmap[0];
 126} ____cacheline_aligned_in_smp;
 127
 128struct cxgbi_ppm {
 129        struct kref refcnt;
 130        struct net_device *ndev;        /* net_device, 1st port */
 131        struct pci_dev *pdev;
 132        void *lldev;
 133        void **ppm_pp;
 134        struct cxgbi_tag_format tformat;
 135        unsigned int ppmax;
 136        unsigned int llimit;
 137        unsigned int base_idx;
 138
 139        unsigned int pool_rsvd;
 140        unsigned int pool_index_max;
 141        struct cxgbi_ppm_pool __percpu *pool;
 142        /* map lock */
 143        spinlock_t map_lock;            /* ppm map lock */
 144        unsigned int bmap_index_max;
 145        unsigned int next;
 146        unsigned long *ppod_bmap;
 147        struct cxgbi_ppod_data ppod_data[0];
 148};
 149
 150#define DDP_THRESHOLD           512
 151
 152#define PPOD_PAGES_SHIFT        2       /*  4 pages per pod */
 153
 154#define IPPOD_SIZE               sizeof(struct cxgbi_pagepod)  /*  64 */
 155#define PPOD_SIZE_SHIFT         6
 156
 157/* page pods are allocated in groups of this size (must be power of 2) */
 158#define PPOD_CLUSTER_SIZE       16U
 159
 160#define ULPMEM_DSGL_MAX_NPPODS  16      /*  1024/PPOD_SIZE */
 161#define ULPMEM_IDATA_MAX_NPPODS 3       /* (PPOD_SIZE * 3 + ulptx hdr) < 256B */
 162#define PCIE_MEMWIN_MAX_NPPODS  16      /*  1024/PPOD_SIZE */
 163
 164#define PPOD_COLOR_SHIFT        0
 165#define PPOD_COLOR(x)           ((x) << PPOD_COLOR_SHIFT)
 166
 167#define PPOD_IDX_SHIFT          6
 168#define PPOD_IDX_MAX_SIZE       24
 169
 170#define PPOD_TID_SHIFT          0
 171#define PPOD_TID(x)             ((x) << PPOD_TID_SHIFT)
 172
 173#define PPOD_TAG_SHIFT          6
 174#define PPOD_TAG(x)             ((x) << PPOD_TAG_SHIFT)
 175
 176#define PPOD_VALID_SHIFT        24
 177#define PPOD_VALID(x)           ((x) << PPOD_VALID_SHIFT)
 178#define PPOD_VALID_FLAG         PPOD_VALID(1U)
 179
 180#define PPOD_PI_EXTRACT_CTL_SHIFT       31
 181#define PPOD_PI_EXTRACT_CTL(x)          ((x) << PPOD_PI_EXTRACT_CTL_SHIFT)
 182#define PPOD_PI_EXTRACT_CTL_FLAG        V_PPOD_PI_EXTRACT_CTL(1U)
 183
 184#define PPOD_PI_TYPE_SHIFT              29
 185#define PPOD_PI_TYPE_MASK               0x3
 186#define PPOD_PI_TYPE(x)                 ((x) << PPOD_PI_TYPE_SHIFT)
 187
 188#define PPOD_PI_CHECK_CTL_SHIFT         27
 189#define PPOD_PI_CHECK_CTL_MASK          0x3
 190#define PPOD_PI_CHECK_CTL(x)            ((x) << PPOD_PI_CHECK_CTL_SHIFT)
 191
 192#define PPOD_PI_REPORT_CTL_SHIFT        25
 193#define PPOD_PI_REPORT_CTL_MASK         0x3
 194#define PPOD_PI_REPORT_CTL(x)           ((x) << PPOD_PI_REPORT_CTL_SHIFT)
 195
 196static inline int cxgbi_ppm_is_ddp_tag(struct cxgbi_ppm *ppm, u32 tag)
 197{
 198        return !(tag & ppm->tformat.no_ddp_mask);
 199}
 200
 201static inline int cxgbi_ppm_sw_tag_is_usable(struct cxgbi_ppm *ppm,
 202                                             u32 tag)
 203{
 204        /* the sw tag must be using <= 31 bits */
 205        return !(tag & 0x80000000U);
 206}
 207
 208static inline int cxgbi_ppm_make_non_ddp_tag(struct cxgbi_ppm *ppm,
 209                                             u32 sw_tag,
 210                                             u32 *final_tag)
 211{
 212        struct cxgbi_tag_format *tformat = &ppm->tformat;
 213
 214        if (!cxgbi_ppm_sw_tag_is_usable(ppm, sw_tag)) {
 215                pr_info("sw_tag 0x%x NOT usable.\n", sw_tag);
 216                return -EINVAL;
 217        }
 218
 219        if (!sw_tag) {
 220                *final_tag = tformat->no_ddp_mask;
 221        } else {
 222                unsigned int shift = tformat->idx_bits + tformat->color_bits;
 223                u32 lower = sw_tag & tformat->idx_clr_mask;
 224                u32 upper = (sw_tag >> shift) << (shift + 1);
 225
 226                *final_tag = upper | tformat->no_ddp_mask | lower;
 227        }
 228        return 0;
 229}
 230
 231static inline u32 cxgbi_ppm_decode_non_ddp_tag(struct cxgbi_ppm *ppm,
 232                                               u32 tag)
 233{
 234        struct cxgbi_tag_format *tformat = &ppm->tformat;
 235        unsigned int shift = tformat->idx_bits + tformat->color_bits;
 236        u32 lower = tag & tformat->idx_clr_mask;
 237        u32 upper = (tag >> tformat->rsvd_bits) << shift;
 238
 239        return upper | lower;
 240}
 241
 242static inline u32 cxgbi_ppm_ddp_tag_get_idx(struct cxgbi_ppm *ppm,
 243                                            u32 ddp_tag)
 244{
 245        u32 hw_idx = (ddp_tag >> PPOD_IDX_SHIFT) &
 246                        ppm->tformat.idx_mask;
 247
 248        return hw_idx - ppm->base_idx;
 249}
 250
 251static inline u32 cxgbi_ppm_make_ddp_tag(unsigned int hw_idx,
 252                                         unsigned char color)
 253{
 254        return (hw_idx << PPOD_IDX_SHIFT) | ((u32)color);
 255}
 256
 257static inline unsigned long
 258cxgbi_ppm_get_tag_caller_data(struct cxgbi_ppm *ppm,
 259                              u32 ddp_tag)
 260{
 261        u32 idx = cxgbi_ppm_ddp_tag_get_idx(ppm, ddp_tag);
 262
 263        return ppm->ppod_data[idx].caller_data;
 264}
 265
 266/* sw bits are the free bits */
 267static inline int cxgbi_ppm_ddp_tag_update_sw_bits(struct cxgbi_ppm *ppm,
 268                                                   u32 val, u32 orig_tag,
 269                                                   u32 *final_tag)
 270{
 271        struct cxgbi_tag_format *tformat = &ppm->tformat;
 272        u32 v = val >> tformat->free_bits;
 273
 274        if (v) {
 275                pr_info("sw_bits 0x%x too large, avail bits %u.\n",
 276                        val, tformat->free_bits);
 277                return -EINVAL;
 278        }
 279        if (!cxgbi_ppm_is_ddp_tag(ppm, orig_tag))
 280                return -EINVAL;
 281
 282        *final_tag = (val << tformat->rsvd_bits) |
 283                     (orig_tag & ppm->tformat.rsvd_mask);
 284        return 0;
 285}
 286
 287static inline void cxgbi_ppm_ppod_clear(struct cxgbi_pagepod *ppod)
 288{
 289        ppod->hdr.vld_tid = 0U;
 290}
 291
 292static inline void cxgbi_tagmask_check(unsigned int tagmask,
 293                                       struct cxgbi_tag_format *tformat)
 294{
 295        unsigned int bits = fls(tagmask);
 296
 297        /* reserve top most 2 bits for page selector */
 298        tformat->free_bits = 32 - 2 - bits;
 299        tformat->rsvd_bits = bits;
 300        tformat->color_bits = PPOD_IDX_SHIFT;
 301        tformat->idx_bits = bits - 1 - PPOD_IDX_SHIFT;
 302        tformat->no_ddp_mask = 1 << (bits - 1);
 303        tformat->idx_mask = (1 << tformat->idx_bits) - 1;
 304        tformat->color_mask = (1 << PPOD_IDX_SHIFT) - 1;
 305        tformat->idx_clr_mask = (1 << (bits - 1)) - 1;
 306        tformat->rsvd_mask = (1 << bits) - 1;
 307
 308        pr_info("ippm: tagmask 0x%x, rsvd %u=%u+%u+1, mask 0x%x,0x%x, "
 309                "pg %u,%u,%u,%u.\n",
 310                tagmask, tformat->rsvd_bits, tformat->idx_bits,
 311                tformat->color_bits, tformat->no_ddp_mask, tformat->rsvd_mask,
 312                tformat->pgsz_order[0], tformat->pgsz_order[1],
 313                tformat->pgsz_order[2], tformat->pgsz_order[3]);
 314}
 315
 316int cxgbi_ppm_find_page_index(struct cxgbi_ppm *ppm, unsigned long pgsz);
 317void cxgbi_ppm_make_ppod_hdr(struct cxgbi_ppm *ppm, u32 tag,
 318                             unsigned int tid, unsigned int offset,
 319                             unsigned int length,
 320                             struct cxgbi_pagepod_hdr *hdr);
 321void cxgbi_ppm_ppod_release(struct cxgbi_ppm *, u32 idx);
 322int cxgbi_ppm_ppods_reserve(struct cxgbi_ppm *, unsigned short nr_pages,
 323                            u32 per_tag_pg_idx, u32 *ppod_idx, u32 *ddp_tag,
 324                            unsigned long caller_data);
 325int cxgbi_ppm_init(void **ppm_pp, struct net_device *, struct pci_dev *,
 326                   void *lldev, struct cxgbi_tag_format *,
 327                   unsigned int ppmax, unsigned int llimit,
 328                   unsigned int start,
 329                   unsigned int reserve_factor);
 330int cxgbi_ppm_release(struct cxgbi_ppm *ppm);
 331void cxgbi_tagmask_check(unsigned int tagmask, struct cxgbi_tag_format *);
 332unsigned int cxgbi_tagmask_set(unsigned int ppmax);
 333
 334#endif  /*__LIBCXGB_PPM_H__*/
 335