drivers/net/ethernet/cisco/enic/vnic_rq.c

   1 /*
   2  * Copyright 2008-2010 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
  20 #include <linux/kernel.h>
  21 #include <linux/errno.h>
  22 #include <linux/types.h>
  23 #include <linux/pci.h>
  24 #include <linux/delay.h>
  25 #include <linux/slab.h>
  26
  27 #include "vnic_dev.h"
  28 #include "vnic_rq.h"
  29
  30 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
  31 {
  32         struct vnic_rq_buf *buf;
  33         struct vnic_dev *vdev;
  34         unsigned int i, j, count = rq->ring.desc_count;
  35         unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
  36
  37         vdev = rq->vdev;
  38
  39         for (i = 0; i < blks; i++) {
  40                 rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ(count), GFP_ATOMIC);
  41                 if (!rq->bufs[i]) {
  42                         pr_err("Failed to alloc rq_bufs\n");
  43                         return -ENOMEM;
  44                 }
  45         }
  46
  47         for (i = 0; i < blks; i++) {
  48                 buf = rq->bufs[i];
  49                 for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES(count); j++) {
  50                         buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES(count) + j;
  51                         buf->desc = (u8 *)rq->ring.descs +
  52                                 rq->ring.desc_size * buf->index;
  53                         if (buf->index + 1 == count) {
  54                                 buf->next = rq->bufs[0];
  55                                 break;
  56                         } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES(count)) {
  57                                 buf->next = rq->bufs[i + 1];
  58                         } else {
  59                                 buf->next = buf + 1;
  60                                 buf++;
  61                         }
  62                 }
  63         }
  64
  65         rq->to_use = rq->to_clean = rq->bufs[0];
  66
  67         return 0;
  68 }
  69
  70 void vnic_rq_free(struct vnic_rq *rq)
  71 {
  72         struct vnic_dev *vdev;
  73         unsigned int i;
  74
  75         vdev = rq->vdev;
  76
  77         vnic_dev_free_desc_ring(vdev, &rq->ring);
  78
  79         for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
  80                 if (rq->bufs[i]) {
  81                         kfree(rq->bufs[i]);
  82                         rq->bufs[i] = NULL;
  83                 }
  84         }
  85
  86         rq->ctrl = NULL;
  87 }
  88
  89 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
  90         unsigned int desc_count, unsigned int desc_size)
  91 {
  92         int err;
  93
  94         rq->index = index;
  95         rq->vdev = vdev;
  96
  97         rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
  98         if (!rq->ctrl) {
  99                 pr_err("Failed to hook RQ[%d] resource\n", index);
 100                 return -EINVAL;
 101         }
 102
 103         vnic_rq_disable(rq);
 104
 105         err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
 106         if (err)
 107                 return err;
 108
 109         err = vnic_rq_alloc_bufs(rq);
 110         if (err) {
 111                 vnic_rq_free(rq);
 112                 return err;
 113         }
 114
 115         return 0;
 116 }
 117
 118 static void vnic_rq_init_start(struct vnic_rq *rq, unsigned int cq_index,
 119         unsigned int fetch_index, unsigned int posted_index,
 120         unsigned int error_interrupt_enable,
 121         unsigned int error_interrupt_offset)
 122 {
 123         u64 paddr;
 124         unsigned int count = rq->ring.desc_count;
 125
 126         paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
 127         writeq(paddr, &rq->ctrl->ring_base);
 128         iowrite32(count, &rq->ctrl->ring_size);
 129         iowrite32(cq_index, &rq->ctrl->cq_index);
 130         iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
 131         iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
 132         iowrite32(0, &rq->ctrl->dropped_packet_count);
 133         iowrite32(0, &rq->ctrl->error_status);
 134         iowrite32(fetch_index, &rq->ctrl->fetch_index);
 135         iowrite32(posted_index, &rq->ctrl->posted_index);
 136
 137         rq->to_use = rq->to_clean =
 138                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
 139                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
 140 }
 141
 142 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
 143         unsigned int error_interrupt_enable,
 144         unsigned int error_interrupt_offset)
 145 {
 146         u32 fetch_index;
 147
 148         /* Use current fetch_index as the ring starting point */
 149         fetch_index = ioread32(&rq->ctrl->fetch_index);
 150
 151         if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
 152                 /* Hardware surprise removal: reset fetch_index */
 153                 fetch_index = 0;
 154         }
 155
 156         vnic_rq_init_start(rq, cq_index,
 157                 fetch_index, fetch_index,
 158                 error_interrupt_enable,
 159                 error_interrupt_offset);
 160 }
 161
 162 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
 163 {
 164         return ioread32(&rq->ctrl->error_status);
 165 }
 166
 167 void vnic_rq_enable(struct vnic_rq *rq)
 168 {
 169         iowrite32(1, &rq->ctrl->enable);
 170 }
 171
 172 int vnic_rq_disable(struct vnic_rq *rq)
 173 {
 174         unsigned int wait;
 175
 176         iowrite32(0, &rq->ctrl->enable);
 177
 178         /* Wait for HW to ACK disable request */
 179         for (wait = 0; wait < 1000; wait++) {
 180                 if (!(ioread32(&rq->ctrl->running)))
 181                         return 0;
 182                 udelay(10);
 183         }
 184
 185         pr_err("Failed to disable RQ[%d]\n", rq->index);
 186
 187         return -ETIMEDOUT;
 188 }
 189
 190 void vnic_rq_clean(struct vnic_rq *rq,
 191         void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
 192 {
 193         struct vnic_rq_buf *buf;
 194         u32 fetch_index;
 195         unsigned int count = rq->ring.desc_count;
 196
 197         buf = rq->to_clean;
 198
 199         while (vnic_rq_desc_used(rq) > 0) {
 200
 201                 (*buf_clean)(rq, buf);
 202
 203                 buf = rq->to_clean = buf->next;
 204                 rq->ring.desc_avail++;
 205         }
 206
 207         /* Use current fetch_index as the ring starting point */
 208         fetch_index = ioread32(&rq->ctrl->fetch_index);
 209
 210         if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
 211                 /* Hardware surprise removal: reset fetch_index */
 212                 fetch_index = 0;
 213         }
 214         rq->to_use = rq->to_clean =
 215                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
 216                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
 217         iowrite32(fetch_index, &rq->ctrl->posted_index);
 218
 219         vnic_dev_clear_desc_ring(&rq->ring);
 220 }
 221