drivers/infiniband/hw/amso1100/c2_intr.c

   1 /*
   2  * Copyright (c) 2005 Ammasso, Inc. All rights reserved.
   3  * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33 #include "c2.h"
  34 #include <rdma/iw_cm.h>
  35 #include "c2_vq.h"
  36
  37 static void handle_mq(struct c2_dev *c2dev, u32 index);
  38 static void handle_vq(struct c2_dev *c2dev, u32 mq_index);
  39
  40 /*
  41  * Handle RNIC interrupts
  42  */
  43 void c2_rnic_interrupt(struct c2_dev *c2dev)
  44 {
  45         unsigned int mq_index;
  46
  47         while (c2dev->hints_read != be16_to_cpu(*c2dev->hint_count)) {
  48                 mq_index = readl(c2dev->regs + PCI_BAR0_HOST_HINT);
  49                 if (mq_index & 0x80000000) {
  50                         break;
  51                 }
  52
  53                 c2dev->hints_read++;
  54                 handle_mq(c2dev, mq_index);
  55         }
  56
  57 }
  58
  59 /*
  60  * Top level MQ handler
  61  */
  62 static void handle_mq(struct c2_dev *c2dev, u32 mq_index)
  63 {
  64         if (c2dev->qptr_array[mq_index] == NULL) {
  65                 pr_debug(KERN_INFO "handle_mq: stray activity for mq_index=%d\n",
  66                         mq_index);
  67                 return;
  68         }
  69
  70         switch (mq_index) {
  71         case (0):
  72                 /*
  73                  * An index of 0 in the activity queue
  74                  * indicates the req vq now has messages
  75                  * available...
  76                  *
  77                  * Wake up any waiters waiting on req VQ
  78                  * message availability.
  79                  */
  80                 wake_up(&c2dev->req_vq_wo);
  81                 break;
  82         case (1):
  83                 handle_vq(c2dev, mq_index);
  84                 break;
  85         case (2):
  86                 /* We have to purge the VQ in case there are pending
  87                  * accept reply requests that would result in the
  88                  * generation of an ESTABLISHED event. If we don't
  89                  * generate these first, a CLOSE event could end up
  90                  * being delivered before the ESTABLISHED event.
  91                  */
  92                 handle_vq(c2dev, 1);
  93
  94                 c2_ae_event(c2dev, mq_index);
  95                 break;
  96         default:
  97                 /* There is no event synchronization between CQ events
  98                  * and AE or CM events. In fact, CQE could be
  99                  * delivered for all of the I/O up to and including the
 100                  * FLUSH for a peer disconenct prior to the ESTABLISHED
 101                  * event being delivered to the app. The reason for this
 102                  * is that CM events are delivered on a thread, while AE
 103                  * and CM events are delivered on interrupt context.
 104                  */
 105                 c2_cq_event(c2dev, mq_index);
 106                 break;
 107         }
 108
 109         return;
 110 }
 111
 112 /*
 113  * Handles verbs WR replies.
 114  */
 115 static void handle_vq(struct c2_dev *c2dev, u32 mq_index)
 116 {
 117         void *adapter_msg, *reply_msg;
 118         struct c2wr_hdr *host_msg;
 119         struct c2wr_hdr tmp;
 120         struct c2_mq *reply_vq;
 121         struct c2_vq_req *req;
 122         struct iw_cm_event cm_event;
 123         int err;
 124
 125         reply_vq = (struct c2_mq *) c2dev->qptr_array[mq_index];
 126
 127         /*
 128          * get next msg from mq_index into adapter_msg.
 129          * don't free it yet.
 130          */
 131         adapter_msg = c2_mq_consume(reply_vq);
 132         if (adapter_msg == NULL) {
 133                 return;
 134         }
 135
 136         host_msg = vq_repbuf_alloc(c2dev);
 137
 138         /*
 139          * If we can't get a host buffer, then we'll still
 140          * wakeup the waiter, we just won't give him the msg.
 141          * It is assumed the waiter will deal with this...
 142          */
 143         if (!host_msg) {
 144                 pr_debug("handle_vq: no repbufs!\n");
 145
 146                 /*
 147                  * just copy the WR header into a local variable.
 148                  * this allows us to still demux on the context
 149                  */
 150                 host_msg = &tmp;
 151                 memcpy(host_msg, adapter_msg, sizeof(tmp));
 152                 reply_msg = NULL;
 153         } else {
 154                 memcpy(host_msg, adapter_msg, reply_vq->msg_size);
 155                 reply_msg = host_msg;
 156         }
 157
 158         /*
 159          * consume the msg from the MQ
 160          */
 161         c2_mq_free(reply_vq);
 162
 163         /*
 164          * wakeup the waiter.
 165          */
 166         req = (struct c2_vq_req *) (unsigned long) host_msg->context;
 167         if (req == NULL) {
 168                 /*
 169                  * We should never get here, as the adapter should
 170                  * never send us a reply that we're not expecting.
 171                  */
 172                 vq_repbuf_free(c2dev, host_msg);
 173                 pr_debug("handle_vq: UNEXPECTEDLY got NULL req\n");
 174                 return;
 175         }
 176
 177         if (reply_msg)
 178                 err = c2_errno(reply_msg);
 179         else
 180                 err = -ENOMEM;
 181
 182         if (!err) switch (req->event) {
 183         case IW_CM_EVENT_ESTABLISHED:
 184                 c2_set_qp_state(req->qp,
 185                                 C2_QP_STATE_RTS);
 186         case IW_CM_EVENT_CLOSE:
 187
 188                 /*
 189                  * Move the QP to RTS if this is
 190                  * the established event
 191                  */
 192                 cm_event.event = req->event;
 193                 cm_event.status = 0;
 194                 cm_event.local_addr = req->cm_id->local_addr;
 195                 cm_event.remote_addr = req->cm_id->remote_addr;
 196                 cm_event.private_data = NULL;
 197                 cm_event.private_data_len = 0;
 198                 req->cm_id->event_handler(req->cm_id, &cm_event);
 199                 break;
 200         default:
 201                 break;
 202         }
 203
 204         req->reply_msg = (u64) (unsigned long) (reply_msg);
 205         atomic_set(&req->reply_ready, 1);
 206         wake_up(&req->wait_object);
 207
 208         /*
 209          * If the request was cancelled, then this put will
 210          * free the vq_req memory...and reply_msg!!!
 211          */
 212         vq_req_put(c2dev, req);
 213 }