drivers/scsi/snic/vnic_wq.c

   1 /*
   2  * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
   3  *
   4  * This program is free software; you may redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   9  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  10  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  11  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  12  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  13  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  14  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  15  * SOFTWARE.
  16  */
  17
  18 #include <linux/errno.h>
  19 #include <linux/types.h>
  20 #include <linux/pci.h>
  21 #include <linux/delay.h>
  22 #include <linux/slab.h>
  23 #include "vnic_dev.h"
  24 #include "vnic_wq.h"
  25
  26 static inline int vnic_wq_get_ctrl(struct vnic_dev *vdev, struct vnic_wq *wq,
  27         unsigned int index, enum vnic_res_type res_type)
  28 {
  29         wq->ctrl = svnic_dev_get_res(vdev, res_type, index);
  30         if (!wq->ctrl)
  31                 return -EINVAL;
  32
  33         return 0;
  34 }
  35
  36 static inline int vnic_wq_alloc_ring(struct vnic_dev *vdev, struct vnic_wq *wq,
  37         unsigned int index, unsigned int desc_count, unsigned int desc_size)
  38 {
  39         return svnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count,
  40                                          desc_size);
  41 }
  42
  43 static int vnic_wq_alloc_bufs(struct vnic_wq *wq)
  44 {
  45         struct vnic_wq_buf *buf;
  46         unsigned int i, j, count = wq->ring.desc_count;
  47         unsigned int blks = VNIC_WQ_BUF_BLKS_NEEDED(count);
  48
  49         for (i = 0; i < blks; i++) {
  50                 wq->bufs[i] = kzalloc(VNIC_WQ_BUF_BLK_SZ, GFP_ATOMIC);
  51                 if (!wq->bufs[i]) {
  52                         pr_err("Failed to alloc wq_bufs\n");
  53
  54                         return -ENOMEM;
  55                 }
  56         }
  57
  58         for (i = 0; i < blks; i++) {
  59                 buf = wq->bufs[i];
  60                 for (j = 0; j < VNIC_WQ_BUF_DFLT_BLK_ENTRIES; j++) {
  61                         buf->index = i * VNIC_WQ_BUF_DFLT_BLK_ENTRIES + j;
  62                         buf->desc = (u8 *)wq->ring.descs +
  63                                 wq->ring.desc_size * buf->index;
  64                         if (buf->index + 1 == count) {
  65                                 buf->next = wq->bufs[0];
  66                                 break;
  67                         } else if (j + 1 == VNIC_WQ_BUF_DFLT_BLK_ENTRIES) {
  68                                 buf->next = wq->bufs[i + 1];
  69                         } else {
  70                                 buf->next = buf + 1;
  71                                 buf++;
  72                         }
  73                 }
  74         }
  75
  76         wq->to_use = wq->to_clean = wq->bufs[0];
  77
  78         return 0;
  79 }
  80
  81 void svnic_wq_free(struct vnic_wq *wq)
  82 {
  83         struct vnic_dev *vdev;
  84         unsigned int i;
  85
  86         vdev = wq->vdev;
  87
  88         svnic_dev_free_desc_ring(vdev, &wq->ring);
  89
  90         for (i = 0; i < VNIC_WQ_BUF_BLKS_MAX; i++) {
  91                 kfree(wq->bufs[i]);
  92                 wq->bufs[i] = NULL;
  93         }
  94
  95         wq->ctrl = NULL;
  96
  97 }
  98
  99 int vnic_wq_devcmd2_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
 100         unsigned int desc_count, unsigned int desc_size)
 101 {
 102         int err;
 103
 104         wq->index = 0;
 105         wq->vdev = vdev;
 106
 107         err = vnic_wq_get_ctrl(vdev, wq, 0, RES_TYPE_DEVCMD2);
 108         if (err) {
 109                 pr_err("Failed to get devcmd2 resource\n");
 110
 111                 return err;
 112         }
 113
 114         svnic_wq_disable(wq);
 115
 116         err = vnic_wq_alloc_ring(vdev, wq, 0, desc_count, desc_size);
 117         if (err)
 118                 return err;
 119
 120         return 0;
 121 }
 122
 123 int svnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
 124         unsigned int index, unsigned int desc_count, unsigned int desc_size)
 125 {
 126         int err;
 127
 128         wq->index = index;
 129         wq->vdev = vdev;
 130
 131         err = vnic_wq_get_ctrl(vdev, wq, index, RES_TYPE_WQ);
 132         if (err) {
 133                 pr_err("Failed to hook WQ[%d] resource\n", index);
 134
 135                 return err;
 136         }
 137
 138         svnic_wq_disable(wq);
 139
 140         err = vnic_wq_alloc_ring(vdev, wq, index, desc_count, desc_size);
 141         if (err)
 142                 return err;
 143
 144         err = vnic_wq_alloc_bufs(wq);
 145         if (err) {
 146                 svnic_wq_free(wq);
 147
 148                 return err;
 149         }
 150
 151         return 0;
 152 }
 153
 154 void vnic_wq_init_start(struct vnic_wq *wq, unsigned int cq_index,
 155         unsigned int fetch_index, unsigned int posted_index,
 156         unsigned int error_interrupt_enable,
 157         unsigned int error_interrupt_offset)
 158 {
 159         u64 paddr;
 160         unsigned int count = wq->ring.desc_count;
 161
 162         paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
 163         writeq(paddr, &wq->ctrl->ring_base);
 164         iowrite32(count, &wq->ctrl->ring_size);
 165         iowrite32(fetch_index, &wq->ctrl->fetch_index);
 166         iowrite32(posted_index, &wq->ctrl->posted_index);
 167         iowrite32(cq_index, &wq->ctrl->cq_index);
 168         iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
 169         iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
 170         iowrite32(0, &wq->ctrl->error_status);
 171
 172         wq->to_use = wq->to_clean =
 173                 &wq->bufs[fetch_index / VNIC_WQ_BUF_BLK_ENTRIES(count)]
 174                         [fetch_index % VNIC_WQ_BUF_BLK_ENTRIES(count)];
 175 }
 176
 177 void svnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
 178         unsigned int error_interrupt_enable,
 179         unsigned int error_interrupt_offset)
 180 {
 181         vnic_wq_init_start(wq, cq_index, 0, 0, error_interrupt_enable,
 182                            error_interrupt_offset);
 183 }
 184
 185 unsigned int svnic_wq_error_status(struct vnic_wq *wq)
 186 {
 187         return ioread32(&wq->ctrl->error_status);
 188 }
 189
 190 void svnic_wq_enable(struct vnic_wq *wq)
 191 {
 192         iowrite32(1, &wq->ctrl->enable);
 193 }
 194
 195 int svnic_wq_disable(struct vnic_wq *wq)
 196 {
 197         unsigned int wait;
 198
 199         iowrite32(0, &wq->ctrl->enable);
 200
 201         /* Wait for HW to ACK disable request */
 202         for (wait = 0; wait < 100; wait++) {
 203                 if (!(ioread32(&wq->ctrl->running)))
 204                         return 0;
 205                 udelay(1);
 206         }
 207
 208         pr_err("Failed to disable WQ[%d]\n", wq->index);
 209
 210         return -ETIMEDOUT;
 211 }
 212
 213 void svnic_wq_clean(struct vnic_wq *wq,
 214         void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf))
 215 {
 216         struct vnic_wq_buf *buf;
 217
 218         BUG_ON(ioread32(&wq->ctrl->enable));
 219
 220         buf = wq->to_clean;
 221
 222         while (svnic_wq_desc_used(wq) > 0) {
 223
 224                 (*buf_clean)(wq, buf);
 225
 226                 buf = wq->to_clean = buf->next;
 227                 wq->ring.desc_avail++;
 228         }
 229
 230         wq->to_use = wq->to_clean = wq->bufs[0];
 231
 232         iowrite32(0, &wq->ctrl->fetch_index);
 233         iowrite32(0, &wq->ctrl->posted_index);
 234         iowrite32(0, &wq->ctrl->error_status);
 235
 236         svnic_dev_clear_desc_ring(&wq->ring);
 237 }