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 "vnic_dev.h"
  24 #include "vnic_rq.h"
  25
  26 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
  27 {
  28         struct vnic_rq_buf *buf;
  29         struct vnic_dev *vdev;
  30         unsigned int i, j, count = rq->ring.desc_count;
  31         unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
  32
  33         vdev = rq->vdev;
  34
  35         for (i = 0; i < blks; i++) {
  36                 rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
  37                 if (!rq->bufs[i]) {
  38                         printk(KERN_ERR "Failed to alloc rq_bufs\n");
  39                         return -ENOMEM;
  40                 }
  41         }
  42
  43         for (i = 0; i < blks; i++) {
  44                 buf = rq->bufs[i];
  45                 for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
  46                         buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
  47                         buf->desc = (u8 *)rq->ring.descs +
  48                                 rq->ring.desc_size * buf->index;
  49                         if (buf->index + 1 == count) {
  50                                 buf->next = rq->bufs[0];
  51                                 break;
  52                         } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
  53                                 buf->next = rq->bufs[i + 1];
  54                         } else {
  55                                 buf->next = buf + 1;
  56                                 buf++;
  57                         }
  58                 }
  59         }
  60
  61         rq->to_use = rq->to_clean = rq->bufs[0];
  62         rq->buf_index = 0;
  63
  64         return 0;
  65 }
  66
  67 void vnic_rq_free(struct vnic_rq *rq)
  68 {
  69         struct vnic_dev *vdev;
  70         unsigned int i;
  71
  72         vdev = rq->vdev;
  73
  74         vnic_dev_free_desc_ring(vdev, &rq->ring);
  75
  76         for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
  77                 kfree(rq->bufs[i]);
  78                 rq->bufs[i] = NULL;
  79         }
  80
  81         rq->ctrl = NULL;
  82 }
  83
  84 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
  85         unsigned int desc_count, unsigned int desc_size)
  86 {
  87         int err;
  88
  89         rq->index = index;
  90         rq->vdev = vdev;
  91
  92         rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
  93         if (!rq->ctrl) {
  94                 printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
  95                 return -EINVAL;
  96         }
  97
  98         vnic_rq_disable(rq);
  99
 100         err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
 101         if (err)
 102                 return err;
 103
 104         err = vnic_rq_alloc_bufs(rq);
 105         if (err) {
 106                 vnic_rq_free(rq);
 107                 return err;
 108         }
 109
 110         return 0;
 111 }
 112
 113 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
 114         unsigned int error_interrupt_enable,
 115         unsigned int error_interrupt_offset)
 116 {
 117         u64 paddr;
 118         u32 fetch_index;
 119
 120         paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
 121         writeq(paddr, &rq->ctrl->ring_base);
 122         iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
 123         iowrite32(cq_index, &rq->ctrl->cq_index);
 124         iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
 125         iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
 126         iowrite32(0, &rq->ctrl->dropped_packet_count);
 127         iowrite32(0, &rq->ctrl->error_status);
 128
 129         /* Use current fetch_index as the ring starting point */
 130         fetch_index = ioread32(&rq->ctrl->fetch_index);
 131         rq->to_use = rq->to_clean =
 132                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
 133                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
 134         iowrite32(fetch_index, &rq->ctrl->posted_index);
 135
 136         rq->buf_index = 0;
 137 }
 138
 139 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
 140 {
 141         return ioread32(&rq->ctrl->error_status);
 142 }
 143
 144 void vnic_rq_enable(struct vnic_rq *rq)
 145 {
 146         iowrite32(1, &rq->ctrl->enable);
 147 }
 148
 149 int vnic_rq_disable(struct vnic_rq *rq)
 150 {
 151         unsigned int wait;
 152
 153         iowrite32(0, &rq->ctrl->enable);
 154
 155         /* Wait for HW to ACK disable request */
 156         for (wait = 0; wait < 100; wait++) {
 157                 if (!(ioread32(&rq->ctrl->running)))
 158                         return 0;
 159                 udelay(1);
 160         }
 161
 162         printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
 163
 164         return -ETIMEDOUT;
 165 }
 166
 167 void vnic_rq_clean(struct vnic_rq *rq,
 168         void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
 169 {
 170         struct vnic_rq_buf *buf;
 171         u32 fetch_index;
 172
 173         BUG_ON(ioread32(&rq->ctrl->enable));
 174
 175         buf = rq->to_clean;
 176
 177         while (vnic_rq_desc_used(rq) > 0) {
 178
 179                 (*buf_clean)(rq, buf);
 180
 181                 buf = rq->to_clean = buf->next;
 182                 rq->ring.desc_avail++;
 183         }
 184
 185         /* Use current fetch_index as the ring starting point */
 186         fetch_index = ioread32(&rq->ctrl->fetch_index);
 187         rq->to_use = rq->to_clean =
 188                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
 189                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
 190         iowrite32(fetch_index, &rq->ctrl->posted_index);
 191
 192         rq->buf_index = 0;
 193
 194         vnic_dev_clear_desc_ring(&rq->ring);
 195 }
 196