kernel/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         unsigned int i, j, count = rq->ring.desc_count;
  34         unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
  35
  36         for (i = 0; i < blks; i++) {
  37                 rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ(count), GFP_ATOMIC);
  38                 if (!rq->bufs[i])
  39                         return -ENOMEM;
  40         }
  41
  42         for (i = 0; i < blks; i++) {
  43                 buf = rq->bufs[i];
  44                 for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES(count); j++) {
  45                         buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES(count) + j;
  46                         buf->desc = (u8 *)rq->ring.descs +
  47                                 rq->ring.desc_size * buf->index;
  48                         if (buf->index + 1 == count) {
  49                                 buf->next = rq->bufs[0];
  50                                 break;
  51                         } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES(count)) {
  52                                 buf->next = rq->bufs[i + 1];
  53                         } else {
  54                                 buf->next = buf + 1;
  55                                 buf++;
  56                         }
  57                 }
  58         }
  59
  60         rq->to_use = rq->to_clean = rq->bufs[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                 if (rq->bufs[i]) {
  76                         kfree(rq->bufs[i]);
  77                         rq->bufs[i] = NULL;
  78                 }
  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                 pr_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 static void vnic_rq_init_start(struct vnic_rq *rq, unsigned int cq_index,
 114         unsigned int fetch_index, unsigned int posted_index,
 115         unsigned int error_interrupt_enable,
 116         unsigned int error_interrupt_offset)
 117 {
 118         u64 paddr;
 119         unsigned int count = rq->ring.desc_count;
 120
 121         paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
 122         writeq(paddr, &rq->ctrl->ring_base);
 123         iowrite32(count, &rq->ctrl->ring_size);
 124         iowrite32(cq_index, &rq->ctrl->cq_index);
 125         iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
 126         iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
 127         iowrite32(0, &rq->ctrl->dropped_packet_count);
 128         iowrite32(0, &rq->ctrl->error_status);
 129         iowrite32(fetch_index, &rq->ctrl->fetch_index);
 130         iowrite32(posted_index, &rq->ctrl->posted_index);
 131
 132         rq->to_use = rq->to_clean =
 133                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
 134                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
 135 }
 136
 137 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
 138         unsigned int error_interrupt_enable,
 139         unsigned int error_interrupt_offset)
 140 {
 141         u32 fetch_index = 0;
 142
 143         /* Use current fetch_index as the ring starting point */
 144         fetch_index = ioread32(&rq->ctrl->fetch_index);
 145
 146         if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
 147                 /* Hardware surprise removal: reset fetch_index */
 148                 fetch_index = 0;
 149         }
 150
 151         vnic_rq_init_start(rq, cq_index,
 152                 fetch_index, fetch_index,
 153                 error_interrupt_enable,
 154                 error_interrupt_offset);
 155 }
 156
 157 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
 158 {
 159         return ioread32(&rq->ctrl->error_status);
 160 }
 161
 162 void vnic_rq_enable(struct vnic_rq *rq)
 163 {
 164         iowrite32(1, &rq->ctrl->enable);
 165 }
 166
 167 int vnic_rq_disable(struct vnic_rq *rq)
 168 {
 169         unsigned int wait;
 170
 171         iowrite32(0, &rq->ctrl->enable);
 172
 173         /* Wait for HW to ACK disable request */
 174         for (wait = 0; wait < 1000; wait++) {
 175                 if (!(ioread32(&rq->ctrl->running)))
 176                         return 0;
 177                 udelay(10);
 178         }
 179
 180         pr_err("Failed to disable RQ[%d]\n", rq->index);
 181
 182         return -ETIMEDOUT;
 183 }
 184
 185 void vnic_rq_clean(struct vnic_rq *rq,
 186         void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
 187 {
 188         struct vnic_rq_buf *buf;
 189         u32 fetch_index;
 190         unsigned int count = rq->ring.desc_count;
 191         int i;
 192
 193         buf = rq->to_clean;
 194
 195         for (i = 0; i < rq->ring.desc_count; i++) {
 196                 (*buf_clean)(rq, buf);
 197                 buf = buf->next;
 198         }
 199         rq->ring.desc_avail = rq->ring.desc_count - 1;
 200
 201         /* Use current fetch_index as the ring starting point */
 202         fetch_index = ioread32(&rq->ctrl->fetch_index);
 203
 204         if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
 205                 /* Hardware surprise removal: reset fetch_index */
 206                 fetch_index = 0;
 207         }
 208         rq->to_use = rq->to_clean =
 209                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
 210                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
 211         iowrite32(fetch_index, &rq->ctrl->posted_index);
 212
 213         vnic_dev_clear_desc_ring(&rq->ring);
 214 }
 215