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