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 #ifndef _VNIC_RQ_H_
21 #define _VNIC_RQ_H_
22
23 #include <linux/pci.h>
24
25 #include "vnic_dev.h"
26 #include "vnic_cq.h"
27
28 /* Receive queue control */
29 struct vnic_rq_ctrl {
30 u64 ring_base; /* 0x00 */
31 u32 ring_size; /* 0x08 */
32 u32 pad0;
33 u32 posted_index; /* 0x10 */
34 u32 pad1;
35 u32 cq_index; /* 0x18 */
36 u32 pad2;
37 u32 enable; /* 0x20 */
38 u32 pad3;
39 u32 running; /* 0x28 */
40 u32 pad4;
41 u32 fetch_index; /* 0x30 */
42 u32 pad5;
43 u32 error_interrupt_enable; /* 0x38 */
44 u32 pad6;
45 u32 error_interrupt_offset; /* 0x40 */
46 u32 pad7;
47 u32 error_status; /* 0x48 */
48 u32 pad8;
49 u32 dropped_packet_count; /* 0x50 */
50 u32 pad9;
51 u32 dropped_packet_count_rc; /* 0x58 */
52 u32 pad10;
53 };
54
55 /* Break the vnic_rq_buf allocations into blocks of 64 entries */
56 #define VNIC_RQ_BUF_BLK_ENTRIES 64
57 #define VNIC_RQ_BUF_BLK_SZ \
58 (VNIC_RQ_BUF_BLK_ENTRIES * sizeof(struct vnic_rq_buf))
59 #define VNIC_RQ_BUF_BLKS_NEEDED(entries) \
60 DIV_ROUND_UP(entries, VNIC_RQ_BUF_BLK_ENTRIES)
61 #define VNIC_RQ_BUF_BLKS_MAX VNIC_RQ_BUF_BLKS_NEEDED(4096)
62
63 struct vnic_rq_buf {
64 struct vnic_rq_buf *next;
65 dma_addr_t dma_addr;
66 void *os_buf;
67 unsigned int os_buf_index;
68 unsigned int len;
69 unsigned int index;
70 void *desc;
71 };
72
73 struct vnic_rq {
74 unsigned int index;
75 struct vnic_dev *vdev;
76 struct vnic_rq_ctrl __iomem *ctrl; /* memory-mapped */
77 struct vnic_dev_ring ring;
78 struct vnic_rq_buf *bufs[VNIC_RQ_BUF_BLKS_MAX];
79 struct vnic_rq_buf *to_use;
80 struct vnic_rq_buf *to_clean;
81 void *os_buf_head;
82 unsigned int buf_index;
83 unsigned int pkts_outstanding;
84 };
85
vnic_rq_desc_avail(struct vnic_rq * rq)86 static inline unsigned int vnic_rq_desc_avail(struct vnic_rq *rq)
87 {
88 /* how many does SW own? */
89 return rq->ring.desc_avail;
90 }
91
vnic_rq_desc_used(struct vnic_rq * rq)92 static inline unsigned int vnic_rq_desc_used(struct vnic_rq *rq)
93 {
94 /* how many does HW own? */
95 return rq->ring.desc_count - rq->ring.desc_avail - 1;
96 }
97
vnic_rq_next_desc(struct vnic_rq * rq)98 static inline void *vnic_rq_next_desc(struct vnic_rq *rq)
99 {
100 return rq->to_use->desc;
101 }
102
vnic_rq_next_index(struct vnic_rq * rq)103 static inline unsigned int vnic_rq_next_index(struct vnic_rq *rq)
104 {
105 return rq->to_use->index;
106 }
107
vnic_rq_next_buf_index(struct vnic_rq * rq)108 static inline unsigned int vnic_rq_next_buf_index(struct vnic_rq *rq)
109 {
110 return rq->buf_index++;
111 }
112
vnic_rq_post(struct vnic_rq * rq,void * os_buf,unsigned int os_buf_index,dma_addr_t dma_addr,unsigned int len)113 static inline void vnic_rq_post(struct vnic_rq *rq,
114 void *os_buf, unsigned int os_buf_index,
115 dma_addr_t dma_addr, unsigned int len)
116 {
117 struct vnic_rq_buf *buf = rq->to_use;
118
119 buf->os_buf = os_buf;
120 buf->os_buf_index = os_buf_index;
121 buf->dma_addr = dma_addr;
122 buf->len = len;
123
124 buf = buf->next;
125 rq->to_use = buf;
126 rq->ring.desc_avail--;
127
128 /* Move the posted_index every nth descriptor
129 */
130
131 #ifndef VNIC_RQ_RETURN_RATE
132 #define VNIC_RQ_RETURN_RATE 0xf /* keep 2^n - 1 */
133 #endif
134
135 if ((buf->index & VNIC_RQ_RETURN_RATE) == 0) {
136 /* Adding write memory barrier prevents compiler and/or CPU
137 * reordering, thus avoiding descriptor posting before
138 * descriptor is initialized. Otherwise, hardware can read
139 * stale descriptor fields.
140 */
141 wmb();
142 iowrite32(buf->index, &rq->ctrl->posted_index);
143 }
144 }
145
vnic_rq_return_descs(struct vnic_rq * rq,unsigned int count)146 static inline void vnic_rq_return_descs(struct vnic_rq *rq, unsigned int count)
147 {
148 rq->ring.desc_avail += count;
149 }
150
151 enum desc_return_options {
152 VNIC_RQ_RETURN_DESC,
153 VNIC_RQ_DEFER_RETURN_DESC,
154 };
155
vnic_rq_service(struct vnic_rq * rq,struct cq_desc * cq_desc,u16 completed_index,int desc_return,void (* buf_service)(struct vnic_rq * rq,struct cq_desc * cq_desc,struct vnic_rq_buf * buf,int skipped,void * opaque),void * opaque)156 static inline void vnic_rq_service(struct vnic_rq *rq,
157 struct cq_desc *cq_desc, u16 completed_index,
158 int desc_return, void (*buf_service)(struct vnic_rq *rq,
159 struct cq_desc *cq_desc, struct vnic_rq_buf *buf,
160 int skipped, void *opaque), void *opaque)
161 {
162 struct vnic_rq_buf *buf;
163 int skipped;
164
165 buf = rq->to_clean;
166 while (1) {
167
168 skipped = (buf->index != completed_index);
169
170 (*buf_service)(rq, cq_desc, buf, skipped, opaque);
171
172 if (desc_return == VNIC_RQ_RETURN_DESC)
173 rq->ring.desc_avail++;
174
175 rq->to_clean = buf->next;
176
177 if (!skipped)
178 break;
179
180 buf = rq->to_clean;
181 }
182 }
183
vnic_rq_fill(struct vnic_rq * rq,int (* buf_fill)(struct vnic_rq * rq))184 static inline int vnic_rq_fill(struct vnic_rq *rq,
185 int (*buf_fill)(struct vnic_rq *rq))
186 {
187 int err;
188
189 while (vnic_rq_desc_avail(rq) > 1) {
190
191 err = (*buf_fill)(rq);
192 if (err)
193 return err;
194 }
195
196 return 0;
197 }
198
199 void vnic_rq_free(struct vnic_rq *rq);
200 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
201 unsigned int desc_count, unsigned int desc_size);
202 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
203 unsigned int error_interrupt_enable,
204 unsigned int error_interrupt_offset);
205 unsigned int vnic_rq_error_status(struct vnic_rq *rq);
206 void vnic_rq_enable(struct vnic_rq *rq);
207 int vnic_rq_disable(struct vnic_rq *rq);
208 void vnic_rq_clean(struct vnic_rq *rq,
209 void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf));
210
211 #endif /* _VNIC_RQ_H_ */
212