kernel/drivers/scsi/fnic/vnic_rq.c

   1 /*
   2  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
   3  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
   4  *
   5  * This program is free software; you may redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; version 2 of the License.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  10  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  11  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  12  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  13  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  14  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  15  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  16  * SOFTWARE.
  17  */
  18
  19 #include <linux/errno.h>
  20 #include <linux/types.h>
  21 #include <linux/pci.h>
  22 #include <linux/delay.h>
  23 #include <linux/slab.h>
  24 #include "vnic_dev.h"
  25 #include "vnic_rq.h"
  26
  27 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
  28 {
  29         struct vnic_rq_buf *buf;
  30         struct vnic_dev *vdev;
  31         unsigned int i, j, count = rq->ring.desc_count;
  32         unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
  33
  34         vdev = rq->vdev;
  35
  36         for (i = 0; i < blks; i++) {
  37                 rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
  38                 if (!rq->bufs[i]) {
  39                         printk(KERN_ERR "Failed to alloc rq_bufs\n");
  40                         return -ENOMEM;
  41                 }
  42         }
  43
  44         for (i = 0; i < blks; i++) {
  45                 buf = rq->bufs[i];
  46                 for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
  47                         buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
  48                         buf->desc = (u8 *)rq->ring.descs +
  49                                 rq->ring.desc_size * buf->index;
  50                         if (buf->index + 1 == count) {
  51                                 buf->next = rq->bufs[0];
  52                                 break;
  53                         } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
  54                                 buf->next = rq->bufs[i + 1];
  55                         } else {
  56                                 buf->next = buf + 1;
  57                                 buf++;
  58                         }
  59                 }
  60         }
  61
  62         rq->to_use = rq->to_clean = rq->bufs[0];
  63         rq->buf_index = 0;
  64
  65         return 0;
  66 }
  67
  68 void vnic_rq_free(struct vnic_rq *rq)
  69 {
  70         struct vnic_dev *vdev;
  71         unsigned int i;
  72
  73         vdev = rq->vdev;
  74
  75         vnic_dev_free_desc_ring(vdev, &rq->ring);
  76
  77         for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
  78                 kfree(rq->bufs[i]);
  79                 rq->bufs[i] = NULL;
  80         }
  81
  82         rq->ctrl = NULL;
  83 }
  84
  85 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
  86         unsigned int desc_count, unsigned int desc_size)
  87 {
  88         int err;
  89
  90         rq->index = index;
  91         rq->vdev = vdev;
  92
  93         rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
  94         if (!rq->ctrl) {
  95                 printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
  96                 return -EINVAL;
  97         }
  98
  99         vnic_rq_disable(rq);
 100
 101         err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
 102         if (err)
 103                 return err;
 104
 105         err = vnic_rq_alloc_bufs(rq);
 106         if (err) {
 107                 vnic_rq_free(rq);
 108                 return err;
 109         }
 110
 111         return 0;
 112 }
 113
 114 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
 115         unsigned int error_interrupt_enable,
 116         unsigned int error_interrupt_offset)
 117 {
 118         u64 paddr;
 119         u32 fetch_index;
 120
 121         paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
 122         writeq(paddr, &rq->ctrl->ring_base);
 123         iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
 124         iowrite32(cq_index, &rq->ctrl->cq_index);
 125         iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
 126         iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
 127         iowrite32(0, &rq->ctrl->dropped_packet_count);
 128         iowrite32(0, &rq->ctrl->error_status);
 129
 130         /* Use current fetch_index as the ring starting point */
 131         fetch_index = ioread32(&rq->ctrl->fetch_index);
 132         rq->to_use = rq->to_clean =
 133                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
 134                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
 135         iowrite32(fetch_index, &rq->ctrl->posted_index);
 136
 137         rq->buf_index = 0;
 138 }
 139
 140 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
 141 {
 142         return ioread32(&rq->ctrl->error_status);
 143 }
 144
 145 void vnic_rq_enable(struct vnic_rq *rq)
 146 {
 147         iowrite32(1, &rq->ctrl->enable);
 148 }
 149
 150 int vnic_rq_disable(struct vnic_rq *rq)
 151 {
 152         unsigned int wait;
 153
 154         iowrite32(0, &rq->ctrl->enable);
 155
 156         /* Wait for HW to ACK disable request */
 157         for (wait = 0; wait < 100; wait++) {
 158                 if (!(ioread32(&rq->ctrl->running)))
 159                         return 0;
 160                 udelay(1);
 161         }
 162
 163         printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
 164
 165         return -ETIMEDOUT;
 166 }
 167
 168 void vnic_rq_clean(struct vnic_rq *rq,
 169         void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
 170 {
 171         struct vnic_rq_buf *buf;
 172         u32 fetch_index;
 173
 174         BUG_ON(ioread32(&rq->ctrl->enable));
 175
 176         buf = rq->to_clean;
 177
 178         while (vnic_rq_desc_used(rq) > 0) {
 179
 180                 (*buf_clean)(rq, buf);
 181
 182                 buf = rq->to_clean = buf->next;
 183                 rq->ring.desc_avail++;
 184         }
 185
 186         /* Use current fetch_index as the ring starting point */
 187         fetch_index = ioread32(&rq->ctrl->fetch_index);
 188         rq->to_use = rq->to_clean =
 189                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
 190                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
 191         iowrite32(fetch_index, &rq->ctrl->posted_index);
 192
 193         rq->buf_index = 0;
 194
 195         vnic_dev_clear_desc_ring(&rq->ring);
 196 }
 197