scsi/fnic/vnic_rq.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
0004  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
0005  */
0006
0007 #include <linux/errno.h>
0008 #include <linux/types.h>
0009 #include <linux/pci.h>
0010 #include <linux/delay.h>
0011 #include <linux/slab.h>
0012 #include "vnic_dev.h"
0013 #include "vnic_rq.h"
0014
0015 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
0016 {
0017     struct vnic_rq_buf *buf;
0018     unsigned int i, j, count = rq->ring.desc_count;
0019     unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
0020
0021     for (i = 0; i < blks; i++) {
0022         rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
0023         if (!rq->bufs[i]) {
0024             printk(KERN_ERR "Failed to alloc rq_bufs\n");
0025             return -ENOMEM;
0026         }
0027     }
0028
0029     for (i = 0; i < blks; i++) {
0030         buf = rq->bufs[i];
0031         for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
0032             buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
0033             buf->desc = (u8 *)rq->ring.descs +
0034                 rq->ring.desc_size * buf->index;
0035             if (buf->index + 1 == count) {
0036                 buf->next = rq->bufs[0];
0037                 break;
0038             } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
0039                 buf->next = rq->bufs[i + 1];
0040             } else {
0041                 buf->next = buf + 1;
0042                 buf++;
0043             }
0044         }
0045     }
0046
0047     rq->to_use = rq->to_clean = rq->bufs[0];
0048     rq->buf_index = 0;
0049
0050     return 0;
0051 }
0052
0053 void vnic_rq_free(struct vnic_rq *rq)
0054 {
0055     struct vnic_dev *vdev;
0056     unsigned int i;
0057
0058     vdev = rq->vdev;
0059
0060     vnic_dev_free_desc_ring(vdev, &rq->ring);
0061
0062     for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
0063         kfree(rq->bufs[i]);
0064         rq->bufs[i] = NULL;
0065     }
0066
0067     rq->ctrl = NULL;
0068 }
0069
0070 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
0071     unsigned int desc_count, unsigned int desc_size)
0072 {
0073     int err;
0074
0075     rq->index = index;
0076     rq->vdev = vdev;
0077
0078     rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
0079     if (!rq->ctrl) {
0080         printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
0081         return -EINVAL;
0082     }
0083
0084     vnic_rq_disable(rq);
0085
0086     err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
0087     if (err)
0088         return err;
0089
0090     err = vnic_rq_alloc_bufs(rq);
0091     if (err) {
0092         vnic_rq_free(rq);
0093         return err;
0094     }
0095
0096     return 0;
0097 }
0098
0099 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
0100     unsigned int error_interrupt_enable,
0101     unsigned int error_interrupt_offset)
0102 {
0103     u64 paddr;
0104     u32 fetch_index;
0105
0106     paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
0107     writeq(paddr, &rq->ctrl->ring_base);
0108     iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
0109     iowrite32(cq_index, &rq->ctrl->cq_index);
0110     iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
0111     iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
0112     iowrite32(0, &rq->ctrl->dropped_packet_count);
0113     iowrite32(0, &rq->ctrl->error_status);
0114
0115     /* Use current fetch_index as the ring starting point */
0116     fetch_index = ioread32(&rq->ctrl->fetch_index);
0117     rq->to_use = rq->to_clean =
0118         &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
0119             [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
0120     iowrite32(fetch_index, &rq->ctrl->posted_index);
0121
0122     rq->buf_index = 0;
0123 }
0124
0125 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
0126 {
0127     return ioread32(&rq->ctrl->error_status);
0128 }
0129
0130 void vnic_rq_enable(struct vnic_rq *rq)
0131 {
0132     iowrite32(1, &rq->ctrl->enable);
0133 }
0134
0135 int vnic_rq_disable(struct vnic_rq *rq)
0136 {
0137     unsigned int wait;
0138
0139     iowrite32(0, &rq->ctrl->enable);
0140
0141     /* Wait for HW to ACK disable request */
0142     for (wait = 0; wait < 100; wait++) {
0143         if (!(ioread32(&rq->ctrl->running)))
0144             return 0;
0145         udelay(1);
0146     }
0147
0148     printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
0149
0150     return -ETIMEDOUT;
0151 }
0152
0153 void vnic_rq_clean(struct vnic_rq *rq,
0154     void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
0155 {
0156     struct vnic_rq_buf *buf;
0157     u32 fetch_index;
0158
0159     WARN_ON(ioread32(&rq->ctrl->enable));
0160
0161     buf = rq->to_clean;
0162
0163     while (vnic_rq_desc_used(rq) > 0) {
0164
0165         (*buf_clean)(rq, buf);
0166
0167         buf = rq->to_clean = buf->next;
0168         rq->ring.desc_avail++;
0169     }
0170
0171     /* Use current fetch_index as the ring starting point */
0172     fetch_index = ioread32(&rq->ctrl->fetch_index);
0173     rq->to_use = rq->to_clean =
0174         &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
0175             [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
0176     iowrite32(fetch_index, &rq->ctrl->posted_index);
0177
0178     rq->buf_index = 0;
0179
0180     vnic_dev_clear_desc_ring(&rq->ring);
0181 }