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