xref: /linux/drivers/scsi/fnic/vnic_rq.c (revision cf21f328fcafacf4f96e7a30ef9dceede1076378)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
4  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
5  */
6 
7 #include <linux/errno.h>
8 #include <linux/types.h>
9 #include <linux/pci.h>
10 #include <linux/delay.h>
11 #include <linux/slab.h>
12 #include "vnic_dev.h"
13 #include "vnic_rq.h"
14 
15 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
16 {
17 	struct vnic_rq_buf *buf;
18 	unsigned int i, j, count = rq->ring.desc_count;
19 	unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
20 
21 	for (i = 0; i < blks; i++) {
22 		rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
23 		if (!rq->bufs[i]) {
24 			printk(KERN_ERR "Failed to alloc rq_bufs\n");
25 			return -ENOMEM;
26 		}
27 	}
28 
29 	for (i = 0; i < blks; i++) {
30 		buf = rq->bufs[i];
31 		for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
32 			buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
33 			buf->desc = (u8 *)rq->ring.descs +
34 				rq->ring.desc_size * buf->index;
35 			if (buf->index + 1 == count) {
36 				buf->next = rq->bufs[0];
37 				break;
38 			} else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
39 				buf->next = rq->bufs[i + 1];
40 			} else {
41 				buf->next = buf + 1;
42 				buf++;
43 			}
44 		}
45 	}
46 
47 	rq->to_use = rq->to_clean = rq->bufs[0];
48 	rq->buf_index = 0;
49 
50 	return 0;
51 }
52 
53 void vnic_rq_free(struct vnic_rq *rq)
54 {
55 	struct vnic_dev *vdev;
56 	unsigned int i;
57 
58 	vdev = rq->vdev;
59 
60 	vnic_dev_free_desc_ring(vdev, &rq->ring);
61 
62 	for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
63 		kfree(rq->bufs[i]);
64 		rq->bufs[i] = NULL;
65 	}
66 
67 	rq->ctrl = NULL;
68 }
69 
70 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
71 	unsigned int desc_count, unsigned int desc_size)
72 {
73 	int err;
74 
75 	rq->index = index;
76 	rq->vdev = vdev;
77 
78 	rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
79 	if (!rq->ctrl) {
80 		printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
81 		return -EINVAL;
82 	}
83 
84 	vnic_rq_disable(rq);
85 
86 	err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
87 	if (err)
88 		return err;
89 
90 	err = vnic_rq_alloc_bufs(rq);
91 	if (err) {
92 		vnic_rq_free(rq);
93 		return err;
94 	}
95 
96 	return 0;
97 }
98 
99 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
100 	unsigned int error_interrupt_enable,
101 	unsigned int error_interrupt_offset)
102 {
103 	u64 paddr;
104 	u32 fetch_index;
105 
106 	paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
107 	writeq(paddr, &rq->ctrl->ring_base);
108 	iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
109 	iowrite32(cq_index, &rq->ctrl->cq_index);
110 	iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
111 	iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
112 	iowrite32(0, &rq->ctrl->dropped_packet_count);
113 	iowrite32(0, &rq->ctrl->error_status);
114 
115 	/* Use current fetch_index as the ring starting point */
116 	fetch_index = ioread32(&rq->ctrl->fetch_index);
117 	rq->to_use = rq->to_clean =
118 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
119 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
120 	iowrite32(fetch_index, &rq->ctrl->posted_index);
121 
122 	rq->buf_index = 0;
123 }
124 
125 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
126 {
127 	return ioread32(&rq->ctrl->error_status);
128 }
129 
130 void vnic_rq_enable(struct vnic_rq *rq)
131 {
132 	iowrite32(1, &rq->ctrl->enable);
133 }
134 
135 int vnic_rq_disable(struct vnic_rq *rq)
136 {
137 	unsigned int wait;
138 
139 	iowrite32(0, &rq->ctrl->enable);
140 
141 	/* Wait for HW to ACK disable request */
142 	for (wait = 0; wait < 100; wait++) {
143 		if (!(ioread32(&rq->ctrl->running)))
144 			return 0;
145 		udelay(1);
146 	}
147 
148 	printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
149 
150 	return -ETIMEDOUT;
151 }
152 
153 void vnic_rq_clean(struct vnic_rq *rq,
154 	void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
155 {
156 	struct vnic_rq_buf *buf;
157 	u32 fetch_index;
158 
159 	WARN_ON(ioread32(&rq->ctrl->enable));
160 
161 	buf = rq->to_clean;
162 
163 	while (vnic_rq_desc_used(rq) > 0) {
164 
165 		(*buf_clean)(rq, buf);
166 
167 		buf = rq->to_clean = buf->next;
168 		rq->ring.desc_avail++;
169 	}
170 
171 	/* Use current fetch_index as the ring starting point */
172 	fetch_index = ioread32(&rq->ctrl->fetch_index);
173 	rq->to_use = rq->to_clean =
174 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
175 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
176 	iowrite32(fetch_index, &rq->ctrl->posted_index);
177 
178 	rq->buf_index = 0;
179 
180 	vnic_dev_clear_desc_ring(&rq->ring);
181 }
182