drivers/infiniband/hw/ehca/ipz_pt_fn.h

   1 /*
   2  *  IBM eServer eHCA Infiniband device driver for Linux on POWER
   3  *
   4  *  internal queue handling
   5  *
   6  *  Authors: Waleri Fomin <fomin@de.ibm.com>
   7  *           Reinhard Ernst <rernst@de.ibm.com>
   8  *           Christoph Raisch <raisch@de.ibm.com>
   9  *
  10  *  Copyright (c) 2005 IBM Corporation
  11  *
  12  *  All rights reserved.
  13  *
  14  *  This source code is distributed under a dual license of GPL v2.0 and OpenIB
  15  *  BSD.
  16  *
  17  * OpenIB BSD License
  18  *
  19  * Redistribution and use in source and binary forms, with or without
  20  * modification, are permitted provided that the following conditions are met:
  21  *
  22  * Redistributions of source code must retain the above copyright notice, this
  23  * list of conditions and the following disclaimer.
  24  *
  25  * Redistributions in binary form must reproduce the above copyright notice,
  26  * this list of conditions and the following disclaimer in the documentation
  27  * and/or other materials
  28  * provided with the distribution.
  29  *
  30  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  31  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  33  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  34  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  35  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  36  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  37  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  38  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  39  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  40  * POSSIBILITY OF SUCH DAMAGE.
  41  */
  42
  43 #ifndef __IPZ_PT_FN_H__
  44 #define __IPZ_PT_FN_H__
  45
  46 #define EHCA_PAGESHIFT   12
  47 #define EHCA_PAGESIZE   4096UL
  48 #define EHCA_PAGEMASK   (~(EHCA_PAGESIZE-1))
  49 #define EHCA_PT_ENTRIES 512UL
  50
  51 #include "ehca_tools.h"
  52 #include "ehca_qes.h"
  53
  54 /* struct generic ehca page */
  55 struct ipz_page {
  56         u8 entries[EHCA_PAGESIZE];
  57 };
  58
  59 /* struct generic queue in linux kernel virtual memory (kv) */
  60 struct ipz_queue {
  61         u64 current_q_offset;   /* current queue entry */
  62
  63         struct ipz_page **queue_pages;  /* array of pages belonging to queue */
  64         u32 qe_size;            /* queue entry size */
  65         u32 act_nr_of_sg;
  66         u32 queue_length;       /* queue length allocated in bytes */
  67         u32 pagesize;
  68         u32 toggle_state;       /* toggle flag - per page */
  69         u32 dummy3;             /* 64 bit alignment */
  70 };
  71
  72 /*
  73  * return current Queue Entry for a certain q_offset
  74  * returns address (kv) of Queue Entry
  75  */
  76 static inline void *ipz_qeit_calc(struct ipz_queue *queue, u64 q_offset)
  77 {
  78         struct ipz_page *current_page;
  79         if (q_offset >= queue->queue_length)
  80                 return NULL;
  81         current_page = (queue->queue_pages)[q_offset >> EHCA_PAGESHIFT];
  82         return &current_page->entries[q_offset & (EHCA_PAGESIZE - 1)];
  83 }
  84
  85 /*
  86  * return current Queue Entry
  87  * returns address (kv) of Queue Entry
  88  */
  89 static inline void *ipz_qeit_get(struct ipz_queue *queue)
  90 {
  91         return ipz_qeit_calc(queue, queue->current_q_offset);
  92 }
  93
  94 /*
  95  * return current Queue Page , increment Queue Page iterator from
  96  * page to page in struct ipz_queue, last increment will return 0! and
  97  * NOT wrap
  98  * returns address (kv) of Queue Page
  99  * warning don't use in parallel with ipz_QE_get_inc()
 100  */
 101 void *ipz_qpageit_get_inc(struct ipz_queue *queue);
 102
 103 /*
 104  * return current Queue Entry, increment Queue Entry iterator by one
 105  * step in struct ipz_queue, will wrap in ringbuffer
 106  * returns address (kv) of Queue Entry BEFORE increment
 107  * warning don't use in parallel with ipz_qpageit_get_inc()
 108  * warning unpredictable results may occur if steps>act_nr_of_queue_entries
 109  */
 110 static inline void *ipz_qeit_get_inc(struct ipz_queue *queue)
 111 {
 112         void *ret = ipz_qeit_get(queue);
 113         queue->current_q_offset += queue->qe_size;
 114         if (queue->current_q_offset >= queue->queue_length) {
 115                 queue->current_q_offset = 0;
 116                 /* toggle the valid flag */
 117                 queue->toggle_state = (~queue->toggle_state) & 1;
 118         }
 119
 120         return ret;
 121 }
 122
 123 /*
 124  * return current Queue Entry, increment Queue Entry iterator by one
 125  * step in struct ipz_queue, will wrap in ringbuffer
 126  * returns address (kv) of Queue Entry BEFORE increment
 127  * returns 0 and does not increment, if wrong valid state
 128  * warning don't use in parallel with ipz_qpageit_get_inc()
 129  * warning unpredictable results may occur if steps>act_nr_of_queue_entries
 130  */
 131 static inline void *ipz_qeit_get_inc_valid(struct ipz_queue *queue)
 132 {
 133         struct ehca_cqe *cqe = ipz_qeit_get(queue);
 134         u32 cqe_flags = cqe->cqe_flags;
 135
 136         if ((cqe_flags >> 7) != (queue->toggle_state & 1))
 137                 return NULL;
 138
 139         ipz_qeit_get_inc(queue);
 140         return cqe;
 141 }
 142
 143 static inline int ipz_qeit_is_valid(struct ipz_queue *queue)
 144 {
 145         struct ehca_cqe *cqe = ipz_qeit_get(queue);
 146         u32 cqe_flags = cqe->cqe_flags;
 147
 148         return cqe_flags >> 7 == (queue->toggle_state & 1);
 149 }
 150
 151 /*
 152  * returns and resets Queue Entry iterator
 153  * returns address (kv) of first Queue Entry
 154  */
 155 static inline void *ipz_qeit_reset(struct ipz_queue *queue)
 156 {
 157         queue->current_q_offset = 0;
 158         return ipz_qeit_get(queue);
 159 }
 160
 161 /*
 162  * return the q_offset corresponding to an absolute address
 163  */
 164 int ipz_queue_abs_to_offset(struct ipz_queue *queue, u64 addr, u64 *q_offset);
 165
 166 /*
 167  * return the next queue offset. don't modify the queue.
 168  */
 169 static inline u64 ipz_queue_advance_offset(struct ipz_queue *queue, u64 offset)
 170 {
 171         offset += queue->qe_size;
 172         if (offset >= queue->queue_length) offset = 0;
 173         return offset;
 174 }
 175
 176 /* struct generic page table */
 177 struct ipz_pt {
 178         u64 entries[EHCA_PT_ENTRIES];
 179 };
 180
 181 /* struct page table for a queue, only to be used in pf */
 182 struct ipz_qpt {
 183         /* queue page tables (kv), use u64 because we know the element length */
 184         u64 *qpts;
 185         u32 n_qpts;
 186         u32 n_ptes;       /*  number of page table entries */
 187         u64 *current_pte_addr;
 188 };
 189
 190 /*
 191  * constructor for a ipz_queue_t, placement new for ipz_queue_t,
 192  * new for all dependent datastructors
 193  * all QP Tables are the same
 194  * flow:
 195  *    allocate+pin queue
 196  * see ipz_qpt_ctor()
 197  * returns true if ok, false if out of memory
 198  */
 199 int ipz_queue_ctor(struct ipz_queue *queue, const u32 nr_of_pages,
 200                    const u32 pagesize, const u32 qe_size,
 201                    const u32 nr_of_sg);
 202
 203 /*
 204  * destructor for a ipz_queue_t
 205  *  -# free queue
 206  *  see ipz_queue_ctor()
 207  *  returns true if ok, false if queue was NULL-ptr of free failed
 208  */
 209 int ipz_queue_dtor(struct ipz_queue *queue);
 210
 211 /*
 212  * constructor for a ipz_qpt_t,
 213  * placement new for struct ipz_queue, new for all dependent datastructors
 214  * all QP Tables are the same,
 215  * flow:
 216  * -# allocate+pin queue
 217  * -# initialise ptcb
 218  * -# allocate+pin PTs
 219  * -# link PTs to a ring, according to HCA Arch, set bit62 id needed
 220  * -# the ring must have room for exactly nr_of_PTEs
 221  * see ipz_qpt_ctor()
 222  */
 223 void ipz_qpt_ctor(struct ipz_qpt *qpt,
 224                   const u32 nr_of_qes,
 225                   const u32 pagesize,
 226                   const u32 qe_size,
 227                   const u8 lowbyte, const u8 toggle,
 228                   u32 * act_nr_of_QEs, u32 * act_nr_of_pages);
 229
 230 /*
 231  * return current Queue Entry, increment Queue Entry iterator by one
 232  * step in struct ipz_queue, will wrap in ringbuffer
 233  * returns address (kv) of Queue Entry BEFORE increment
 234  * warning don't use in parallel with ipz_qpageit_get_inc()
 235  * warning unpredictable results may occur if steps>act_nr_of_queue_entries
 236  * fix EQ page problems
 237  */
 238 void *ipz_qeit_eq_get_inc(struct ipz_queue *queue);
 239
 240 /*
 241  * return current Event Queue Entry, increment Queue Entry iterator
 242  * by one step in struct ipz_queue if valid, will wrap in ringbuffer
 243  * returns address (kv) of Queue Entry BEFORE increment
 244  * returns 0 and does not increment, if wrong valid state
 245  * warning don't use in parallel with ipz_queue_QPageit_get_inc()
 246  * warning unpredictable results may occur if steps>act_nr_of_queue_entries
 247  */
 248 static inline void *ipz_eqit_eq_get_inc_valid(struct ipz_queue *queue)
 249 {
 250         void *ret = ipz_qeit_get(queue);
 251         u32 qe = *(u8 *) ret;
 252         if ((qe >> 7) != (queue->toggle_state & 1))
 253                 return NULL;
 254         ipz_qeit_eq_get_inc(queue); /* this is a good one */
 255         return ret;
 256 }
 257
 258 static inline void *ipz_eqit_eq_peek_valid(struct ipz_queue *queue)
 259 {
 260         void *ret = ipz_qeit_get(queue);
 261         u32 qe = *(u8 *) ret;
 262         if ((qe >> 7) != (queue->toggle_state & 1))
 263                 return NULL;
 264         return ret;
 265 }
 266
 267 /* returns address (GX) of first queue entry */
 268 static inline u64 ipz_qpt_get_firstpage(struct ipz_qpt *qpt)
 269 {
 270         return be64_to_cpu(qpt->qpts[0]);
 271 }
 272
 273 /* returns address (kv) of first page of queue page table */
 274 static inline void *ipz_qpt_get_qpt(struct ipz_qpt *qpt)
 275 {
 276         return qpt->qpts;
 277 }
 278
 279 #endif                          /* __IPZ_PT_FN_H__ */