xref: /openbmc/linux/drivers/scsi/fnic/vnic_rq.c (revision 7dd65feb)
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 #include <linux/errno.h>
20 #include <linux/types.h>
21 #include <linux/pci.h>
22 #include <linux/delay.h>
23 #include "vnic_dev.h"
24 #include "vnic_rq.h"
25 
26 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
27 {
28 	struct vnic_rq_buf *buf;
29 	struct vnic_dev *vdev;
30 	unsigned int i, j, count = rq->ring.desc_count;
31 	unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
32 
33 	vdev = rq->vdev;
34 
35 	for (i = 0; i < blks; i++) {
36 		rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
37 		if (!rq->bufs[i]) {
38 			printk(KERN_ERR "Failed to alloc rq_bufs\n");
39 			return -ENOMEM;
40 		}
41 	}
42 
43 	for (i = 0; i < blks; i++) {
44 		buf = rq->bufs[i];
45 		for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
46 			buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
47 			buf->desc = (u8 *)rq->ring.descs +
48 				rq->ring.desc_size * buf->index;
49 			if (buf->index + 1 == count) {
50 				buf->next = rq->bufs[0];
51 				break;
52 			} else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
53 				buf->next = rq->bufs[i + 1];
54 			} else {
55 				buf->next = buf + 1;
56 				buf++;
57 			}
58 		}
59 	}
60 
61 	rq->to_use = rq->to_clean = rq->bufs[0];
62 	rq->buf_index = 0;
63 
64 	return 0;
65 }
66 
67 void vnic_rq_free(struct vnic_rq *rq)
68 {
69 	struct vnic_dev *vdev;
70 	unsigned int i;
71 
72 	vdev = rq->vdev;
73 
74 	vnic_dev_free_desc_ring(vdev, &rq->ring);
75 
76 	for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
77 		kfree(rq->bufs[i]);
78 		rq->bufs[i] = NULL;
79 	}
80 
81 	rq->ctrl = NULL;
82 }
83 
84 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
85 	unsigned int desc_count, unsigned int desc_size)
86 {
87 	int err;
88 
89 	rq->index = index;
90 	rq->vdev = vdev;
91 
92 	rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
93 	if (!rq->ctrl) {
94 		printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
95 		return -EINVAL;
96 	}
97 
98 	vnic_rq_disable(rq);
99 
100 	err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
101 	if (err)
102 		return err;
103 
104 	err = vnic_rq_alloc_bufs(rq);
105 	if (err) {
106 		vnic_rq_free(rq);
107 		return err;
108 	}
109 
110 	return 0;
111 }
112 
113 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
114 	unsigned int error_interrupt_enable,
115 	unsigned int error_interrupt_offset)
116 {
117 	u64 paddr;
118 	u32 fetch_index;
119 
120 	paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
121 	writeq(paddr, &rq->ctrl->ring_base);
122 	iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
123 	iowrite32(cq_index, &rq->ctrl->cq_index);
124 	iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
125 	iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
126 	iowrite32(0, &rq->ctrl->dropped_packet_count);
127 	iowrite32(0, &rq->ctrl->error_status);
128 
129 	/* Use current fetch_index as the ring starting point */
130 	fetch_index = ioread32(&rq->ctrl->fetch_index);
131 	rq->to_use = rq->to_clean =
132 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
133 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
134 	iowrite32(fetch_index, &rq->ctrl->posted_index);
135 
136 	rq->buf_index = 0;
137 }
138 
139 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
140 {
141 	return ioread32(&rq->ctrl->error_status);
142 }
143 
144 void vnic_rq_enable(struct vnic_rq *rq)
145 {
146 	iowrite32(1, &rq->ctrl->enable);
147 }
148 
149 int vnic_rq_disable(struct vnic_rq *rq)
150 {
151 	unsigned int wait;
152 
153 	iowrite32(0, &rq->ctrl->enable);
154 
155 	/* Wait for HW to ACK disable request */
156 	for (wait = 0; wait < 100; wait++) {
157 		if (!(ioread32(&rq->ctrl->running)))
158 			return 0;
159 		udelay(1);
160 	}
161 
162 	printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
163 
164 	return -ETIMEDOUT;
165 }
166 
167 void vnic_rq_clean(struct vnic_rq *rq,
168 	void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
169 {
170 	struct vnic_rq_buf *buf;
171 	u32 fetch_index;
172 
173 	BUG_ON(ioread32(&rq->ctrl->enable));
174 
175 	buf = rq->to_clean;
176 
177 	while (vnic_rq_desc_used(rq) > 0) {
178 
179 		(*buf_clean)(rq, buf);
180 
181 		buf = rq->to_clean = buf->next;
182 		rq->ring.desc_avail++;
183 	}
184 
185 	/* Use current fetch_index as the ring starting point */
186 	fetch_index = ioread32(&rq->ctrl->fetch_index);
187 	rq->to_use = rq->to_clean =
188 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
189 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
190 	iowrite32(fetch_index, &rq->ctrl->posted_index);
191 
192 	rq->buf_index = 0;
193 
194 	vnic_dev_clear_desc_ring(&rq->ring);
195 }
196 
197