xref: /openbmc/linux/drivers/scsi/snic/vnic_cq.h (revision 99a15348)
1 /*
2  * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
3  *
4  * This program is free software; you may redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; version 2 of the License.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
9  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
10  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
11  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
12  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
13  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
14  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
15  * SOFTWARE.
16  */
17 
18 #ifndef _VNIC_CQ_H_
19 #define _VNIC_CQ_H_
20 
21 #include "cq_desc.h"
22 #include "vnic_dev.h"
23 
24 /* Completion queue control */
25 struct vnic_cq_ctrl {
26 	u64 ring_base;			/* 0x00 */
27 	u32 ring_size;			/* 0x08 */
28 	u32 pad0;
29 	u32 flow_control_enable;	/* 0x10 */
30 	u32 pad1;
31 	u32 color_enable;		/* 0x18 */
32 	u32 pad2;
33 	u32 cq_head;			/* 0x20 */
34 	u32 pad3;
35 	u32 cq_tail;			/* 0x28 */
36 	u32 pad4;
37 	u32 cq_tail_color;		/* 0x30 */
38 	u32 pad5;
39 	u32 interrupt_enable;		/* 0x38 */
40 	u32 pad6;
41 	u32 cq_entry_enable;		/* 0x40 */
42 	u32 pad7;
43 	u32 cq_message_enable;		/* 0x48 */
44 	u32 pad8;
45 	u32 interrupt_offset;		/* 0x50 */
46 	u32 pad9;
47 	u64 cq_message_addr;		/* 0x58 */
48 	u32 pad10;
49 };
50 
51 struct vnic_cq {
52 	unsigned int index;
53 	struct vnic_dev *vdev;
54 	struct vnic_cq_ctrl __iomem *ctrl;	/* memory-mapped */
55 	struct vnic_dev_ring ring;
56 	unsigned int to_clean;
57 	unsigned int last_color;
58 };
59 
60 static inline unsigned int svnic_cq_service(struct vnic_cq *cq,
61 	unsigned int work_to_do,
62 	int (*q_service)(struct vnic_dev *vdev, struct cq_desc *cq_desc,
63 	u8 type, u16 q_number, u16 completed_index, void *opaque),
64 	void *opaque)
65 {
66 	struct cq_desc *cq_desc;
67 	unsigned int work_done = 0;
68 	u16 q_number, completed_index;
69 	u8 type, color;
70 
71 	cq_desc = (struct cq_desc *)((u8 *)cq->ring.descs +
72 		cq->ring.desc_size * cq->to_clean);
73 	cq_desc_dec(cq_desc, &type, &color,
74 		&q_number, &completed_index);
75 
76 	while (color != cq->last_color) {
77 
78 		if ((*q_service)(cq->vdev, cq_desc, type,
79 			q_number, completed_index, opaque))
80 			break;
81 
82 		cq->to_clean++;
83 		if (cq->to_clean == cq->ring.desc_count) {
84 			cq->to_clean = 0;
85 			cq->last_color = cq->last_color ? 0 : 1;
86 		}
87 
88 		cq_desc = (struct cq_desc *)((u8 *)cq->ring.descs +
89 			cq->ring.desc_size * cq->to_clean);
90 		cq_desc_dec(cq_desc, &type, &color,
91 			&q_number, &completed_index);
92 
93 		work_done++;
94 		if (work_done >= work_to_do)
95 			break;
96 	}
97 
98 	return work_done;
99 }
100 
101 void svnic_cq_free(struct vnic_cq *cq);
102 int svnic_cq_alloc(struct vnic_dev *vdev, struct vnic_cq *cq,
103 	unsigned int index, unsigned int desc_count, unsigned int desc_size);
104 void svnic_cq_init(struct vnic_cq *cq, unsigned int flow_control_enable,
105 	unsigned int color_enable, unsigned int cq_head, unsigned int cq_tail,
106 	unsigned int cq_tail_color, unsigned int interrupt_enable,
107 	unsigned int cq_entry_enable, unsigned int message_enable,
108 	unsigned int interrupt_offset, u64 message_addr);
109 void svnic_cq_clean(struct vnic_cq *cq);
110 #endif /* _VNIC_CQ_H_ */
111