drivers/scsi/fnic/vnic_rq.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
   4  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
   5  */
   6
   7 #include <linux/errno.h>
   8 #include <linux/types.h>
   9 #include <linux/pci.h>
  10 #include <linux/delay.h>
  11 #include <linux/slab.h>
  12 #include "vnic_dev.h"
  13 #include "vnic_rq.h"
  14
  15 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
  16 {
  17         struct vnic_rq_buf *buf;
  18         unsigned int i, j, count = rq->ring.desc_count;
  19         unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
  20
  21         for (i = 0; i < blks; i++) {
  22                 rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
  23                 if (!rq->bufs[i]) {
  24                         printk(KERN_ERR "Failed to alloc rq_bufs\n");
  25                         return -ENOMEM;
  26                 }
  27         }
  28
  29         for (i = 0; i < blks; i++) {
  30                 buf = rq->bufs[i];
  31                 for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
  32                         buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
  33                         buf->desc = (u8 *)rq->ring.descs +
  34                                 rq->ring.desc_size * buf->index;
  35                         if (buf->index + 1 == count) {
  36                                 buf->next = rq->bufs[0];
  37                                 break;
  38                         } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
  39                                 buf->next = rq->bufs[i + 1];
  40                         } else {
  41                                 buf->next = buf + 1;
  42                                 buf++;
  43                         }
  44                 }
  45         }
  46
  47         rq->to_use = rq->to_clean = rq->bufs[0];
  48         rq->buf_index = 0;
  49
  50         return 0;
  51 }
  52
  53 void vnic_rq_free(struct vnic_rq *rq)
  54 {
  55         struct vnic_dev *vdev;
  56         unsigned int i;
  57
  58         vdev = rq->vdev;
  59
  60         vnic_dev_free_desc_ring(vdev, &rq->ring);
  61
  62         for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
  63                 kfree(rq->bufs[i]);
  64                 rq->bufs[i] = NULL;
  65         }
  66
  67         rq->ctrl = NULL;
  68 }
  69
  70 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
  71         unsigned int desc_count, unsigned int desc_size)
  72 {
  73         int err;
  74
  75         rq->index = index;
  76         rq->vdev = vdev;
  77
  78         rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
  79         if (!rq->ctrl) {
  80                 printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
  81                 return -EINVAL;
  82         }
  83
  84         vnic_rq_disable(rq);
  85
  86         err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
  87         if (err)
  88                 return err;
  89
  90         err = vnic_rq_alloc_bufs(rq);
  91         if (err) {
  92                 vnic_rq_free(rq);
  93                 return err;
  94         }
  95
  96         return 0;
  97 }
  98
  99 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
 100         unsigned int error_interrupt_enable,
 101         unsigned int error_interrupt_offset)
 102 {
 103         u64 paddr;
 104         u32 fetch_index;
 105
 106         paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
 107         writeq(paddr, &rq->ctrl->ring_base);
 108         iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
 109         iowrite32(cq_index, &rq->ctrl->cq_index);
 110         iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
 111         iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
 112         iowrite32(0, &rq->ctrl->dropped_packet_count);
 113         iowrite32(0, &rq->ctrl->error_status);
 114
 115         /* Use current fetch_index as the ring starting point */
 116         fetch_index = ioread32(&rq->ctrl->fetch_index);
 117         rq->to_use = rq->to_clean =
 118                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
 119                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
 120         iowrite32(fetch_index, &rq->ctrl->posted_index);
 121
 122         rq->buf_index = 0;
 123 }
 124
 125 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
 126 {
 127         return ioread32(&rq->ctrl->error_status);
 128 }
 129
 130 void vnic_rq_enable(struct vnic_rq *rq)
 131 {
 132         iowrite32(1, &rq->ctrl->enable);
 133 }
 134
 135 int vnic_rq_disable(struct vnic_rq *rq)
 136 {
 137         unsigned int wait;
 138
 139         iowrite32(0, &rq->ctrl->enable);
 140
 141         /* Wait for HW to ACK disable request */
 142         for (wait = 0; wait < 100; wait++) {
 143                 if (!(ioread32(&rq->ctrl->running)))
 144                         return 0;
 145                 udelay(1);
 146         }
 147
 148         printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
 149
 150         return -ETIMEDOUT;
 151 }
 152
 153 void vnic_rq_clean(struct vnic_rq *rq,
 154         void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
 155 {
 156         struct vnic_rq_buf *buf;
 157         u32 fetch_index;
 158
 159         WARN_ON(ioread32(&rq->ctrl->enable));
 160
 161         buf = rq->to_clean;
 162
 163         while (vnic_rq_desc_used(rq) > 0) {
 164
 165                 (*buf_clean)(rq, buf);
 166
 167                 buf = rq->to_clean = buf->next;
 168                 rq->ring.desc_avail++;
 169         }
 170
 171         /* Use current fetch_index as the ring starting point */
 172         fetch_index = ioread32(&rq->ctrl->fetch_index);
 173         rq->to_use = rq->to_clean =
 174                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
 175                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
 176         iowrite32(fetch_index, &rq->ctrl->posted_index);
 177
 178         rq->buf_index = 0;
 179
 180         vnic_dev_clear_desc_ring(&rq->ring);
 181 }