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#ifndef _VNIC_WQ_H_
21#define _VNIC_WQ_H_
22
23#include <linux/pci.h>
24
25#include "vnic_dev.h"
26#include "vnic_cq.h"
27
28/* Work queue control */
29struct vnic_wq_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 dca_value;			/* 0x38 */
44	u32 pad6;
45	u32 error_interrupt_enable;	/* 0x40 */
46	u32 pad7;
47	u32 error_interrupt_offset;	/* 0x48 */
48	u32 pad8;
49	u32 error_status;		/* 0x50 */
50	u32 pad9;
51};
52
53struct vnic_wq_buf {
54	struct vnic_wq_buf *next;
55	dma_addr_t dma_addr;
56	void *os_buf;
57	unsigned int len;
58	unsigned int index;
59	int sop;
60	void *desc;
61	uint64_t wr_id; /* Cookie */
62	uint8_t cq_entry; /* Gets completion event from hw */
63	uint8_t desc_skip_cnt; /* Num descs to occupy */
64	uint8_t compressed_send; /* Both hdr and payload in one desc */
65	struct vnic_wq_buf *prev;
66};
67
68/* Break the vnic_wq_buf allocations into blocks of 32/64 entries */
69#define VNIC_WQ_BUF_MIN_BLK_ENTRIES 32
70#define VNIC_WQ_BUF_DFLT_BLK_ENTRIES 64
71#define VNIC_WQ_BUF_BLK_ENTRIES(entries) \
72	((unsigned int)((entries < VNIC_WQ_BUF_DFLT_BLK_ENTRIES) ? \
73	VNIC_WQ_BUF_MIN_BLK_ENTRIES : VNIC_WQ_BUF_DFLT_BLK_ENTRIES))
74#define VNIC_WQ_BUF_BLK_SZ(entries) \
75	(VNIC_WQ_BUF_BLK_ENTRIES(entries) * sizeof(struct vnic_wq_buf))
76#define VNIC_WQ_BUF_BLKS_NEEDED(entries) \
77	DIV_ROUND_UP(entries, VNIC_WQ_BUF_BLK_ENTRIES(entries))
78#define VNIC_WQ_BUF_BLKS_MAX VNIC_WQ_BUF_BLKS_NEEDED(4096)
79
80struct vnic_wq {
81	unsigned int index;
82	struct vnic_dev *vdev;
83	struct vnic_wq_ctrl __iomem *ctrl;              /* memory-mapped */
84	struct vnic_dev_ring ring;
85	struct vnic_wq_buf *bufs[VNIC_WQ_BUF_BLKS_MAX];
86	struct vnic_wq_buf *to_use;
87	struct vnic_wq_buf *to_clean;
88	unsigned int pkts_outstanding;
89};
90
91static inline unsigned int vnic_wq_desc_avail(struct vnic_wq *wq)
92{
93	/* how many does SW own? */
94	return wq->ring.desc_avail;
95}
96
97static inline unsigned int vnic_wq_desc_used(struct vnic_wq *wq)
98{
99	/* how many does HW own? */
100	return wq->ring.desc_count - wq->ring.desc_avail - 1;
101}
102
103static inline void *vnic_wq_next_desc(struct vnic_wq *wq)
104{
105	return wq->to_use->desc;
106}
107
108static inline void vnic_wq_doorbell(struct vnic_wq *wq)
109{
110	/* Adding write memory barrier prevents compiler and/or CPU
111	 * reordering, thus avoiding descriptor posting before
112	 * descriptor is initialized. Otherwise, hardware can read
113	 * stale descriptor fields.
114	 */
115	wmb();
116	iowrite32(wq->to_use->index, &wq->ctrl->posted_index);
117}
118
119static inline void vnic_wq_post(struct vnic_wq *wq,
120	void *os_buf, dma_addr_t dma_addr,
121	unsigned int len, int sop, int eop,
122	uint8_t desc_skip_cnt, uint8_t cq_entry,
123	uint8_t compressed_send, uint64_t wrid)
124{
125	struct vnic_wq_buf *buf = wq->to_use;
126
127	buf->sop = sop;
128	buf->cq_entry = cq_entry;
129	buf->compressed_send = compressed_send;
130	buf->desc_skip_cnt = desc_skip_cnt;
131	buf->os_buf = eop ? os_buf : NULL;
132	buf->dma_addr = dma_addr;
133	buf->len = len;
134	buf->wr_id = wrid;
135
136	buf = buf->next;
137	wq->to_use = buf;
138
139	wq->ring.desc_avail -= desc_skip_cnt;
140}
141
142static inline void vnic_wq_service(struct vnic_wq *wq,
143	struct cq_desc *cq_desc, u16 completed_index,
144	void (*buf_service)(struct vnic_wq *wq,
145	struct cq_desc *cq_desc, struct vnic_wq_buf *buf, void *opaque),
146	void *opaque)
147{
148	struct vnic_wq_buf *buf;
149
150	buf = wq->to_clean;
151	while (1) {
152
153		(*buf_service)(wq, cq_desc, buf, opaque);
154
155		wq->ring.desc_avail++;
156
157		wq->to_clean = buf->next;
158
159		if (buf->index == completed_index)
160			break;
161
162		buf = wq->to_clean;
163	}
164}
165
166void vnic_wq_free(struct vnic_wq *wq);
167int vnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq, unsigned int index,
168	unsigned int desc_count, unsigned int desc_size);
169void vnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
170	unsigned int error_interrupt_enable,
171	unsigned int error_interrupt_offset);
172unsigned int vnic_wq_error_status(struct vnic_wq *wq);
173void vnic_wq_enable(struct vnic_wq *wq);
174int vnic_wq_disable(struct vnic_wq *wq);
175void vnic_wq_clean(struct vnic_wq *wq,
176	void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf));
177
178#endif /* _VNIC_WQ_H_ */
179