Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6] / drivers / net / enic / vnic_rq.c
1 /*
2  * Copyright 2008 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
26 #include "vnic_dev.h"
27 #include "vnic_rq.h"
28
29 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
30 {
31         struct vnic_rq_buf *buf;
32         struct vnic_dev *vdev;
33         unsigned int i, j, count = rq->ring.desc_count;
34         unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
35
36         vdev = rq->vdev;
37
38         for (i = 0; i < blks; i++) {
39                 rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
40                 if (!rq->bufs[i]) {
41                         printk(KERN_ERR "Failed to alloc rq_bufs\n");
42                         return -ENOMEM;
43                 }
44         }
45
46         for (i = 0; i < blks; i++) {
47                 buf = rq->bufs[i];
48                 for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
49                         buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
50                         buf->desc = (u8 *)rq->ring.descs +
51                                 rq->ring.desc_size * buf->index;
52                         if (buf->index + 1 == count) {
53                                 buf->next = rq->bufs[0];
54                                 break;
55                         } else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
56                                 buf->next = rq->bufs[i + 1];
57                         } else {
58                                 buf->next = buf + 1;
59                                 buf++;
60                         }
61                 }
62         }
63
64         rq->to_use = rq->to_clean = rq->bufs[0];
65         rq->buf_index = 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                 kfree(rq->bufs[i]);
81                 rq->bufs[i] = NULL;
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                 printk(KERN_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 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
117         unsigned int error_interrupt_enable,
118         unsigned int error_interrupt_offset)
119 {
120         u64 paddr;
121         u32 fetch_index;
122
123         paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
124         writeq(paddr, &rq->ctrl->ring_base);
125         iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
126         iowrite32(cq_index, &rq->ctrl->cq_index);
127         iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
128         iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
129         iowrite32(0, &rq->ctrl->dropped_packet_count);
130         iowrite32(0, &rq->ctrl->error_status);
131
132         /* Use current fetch_index as the ring starting point */
133         fetch_index = ioread32(&rq->ctrl->fetch_index);
134         rq->to_use = rq->to_clean =
135                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
136                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
137         iowrite32(fetch_index, &rq->ctrl->posted_index);
138
139         rq->buf_index = 0;
140 }
141
142 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
143 {
144         return ioread32(&rq->ctrl->error_status);
145 }
146
147 void vnic_rq_enable(struct vnic_rq *rq)
148 {
149         iowrite32(1, &rq->ctrl->enable);
150 }
151
152 int vnic_rq_disable(struct vnic_rq *rq)
153 {
154         unsigned int wait;
155
156         iowrite32(0, &rq->ctrl->enable);
157
158         /* Wait for HW to ACK disable request */
159         for (wait = 0; wait < 100; wait++) {
160                 if (!(ioread32(&rq->ctrl->running)))
161                         return 0;
162                 udelay(1);
163         }
164
165         printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
166
167         return -ETIMEDOUT;
168 }
169
170 void vnic_rq_clean(struct vnic_rq *rq,
171         void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
172 {
173         struct vnic_rq_buf *buf;
174         u32 fetch_index;
175
176         BUG_ON(ioread32(&rq->ctrl->enable));
177
178         buf = rq->to_clean;
179
180         while (vnic_rq_desc_used(rq) > 0) {
181
182                 (*buf_clean)(rq, buf);
183
184                 buf = rq->to_clean = buf->next;
185                 rq->ring.desc_avail++;
186         }
187
188         /* Use current fetch_index as the ring starting point */
189         fetch_index = ioread32(&rq->ctrl->fetch_index);
190         rq->to_use = rq->to_clean =
191                 &rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
192                         [fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
193         iowrite32(fetch_index, &rq->ctrl->posted_index);
194
195         rq->buf_index = 0;
196
197         vnic_dev_clear_desc_ring(&rq->ring);
198 }
199