xref: /openbmc/linux/drivers/scsi/fnic/vnic_wq.c (revision cfbb9be8)
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 <linux/slab.h>
24 #include "vnic_dev.h"
25 #include "vnic_wq.h"
26 
27 static int vnic_wq_alloc_bufs(struct vnic_wq *wq)
28 {
29 	struct vnic_wq_buf *buf;
30 	struct vnic_dev *vdev;
31 	unsigned int i, j, count = wq->ring.desc_count;
32 	unsigned int blks = VNIC_WQ_BUF_BLKS_NEEDED(count);
33 
34 	vdev = wq->vdev;
35 
36 	for (i = 0; i < blks; i++) {
37 		wq->bufs[i] = kzalloc(VNIC_WQ_BUF_BLK_SZ, GFP_ATOMIC);
38 		if (!wq->bufs[i]) {
39 			printk(KERN_ERR "Failed to alloc wq_bufs\n");
40 			return -ENOMEM;
41 		}
42 	}
43 
44 	for (i = 0; i < blks; i++) {
45 		buf = wq->bufs[i];
46 		for (j = 0; j < VNIC_WQ_BUF_BLK_ENTRIES; j++) {
47 			buf->index = i * VNIC_WQ_BUF_BLK_ENTRIES + j;
48 			buf->desc = (u8 *)wq->ring.descs +
49 				wq->ring.desc_size * buf->index;
50 			if (buf->index + 1 == count) {
51 				buf->next = wq->bufs[0];
52 				break;
53 			} else if (j + 1 == VNIC_WQ_BUF_BLK_ENTRIES) {
54 				buf->next = wq->bufs[i + 1];
55 			} else {
56 				buf->next = buf + 1;
57 				buf++;
58 			}
59 		}
60 	}
61 
62 	wq->to_use = wq->to_clean = wq->bufs[0];
63 
64 	return 0;
65 }
66 
67 void vnic_wq_free(struct vnic_wq *wq)
68 {
69 	struct vnic_dev *vdev;
70 	unsigned int i;
71 
72 	vdev = wq->vdev;
73 
74 	vnic_dev_free_desc_ring(vdev, &wq->ring);
75 
76 	for (i = 0; i < VNIC_WQ_BUF_BLKS_MAX; i++) {
77 		kfree(wq->bufs[i]);
78 		wq->bufs[i] = NULL;
79 	}
80 
81 	wq->ctrl = NULL;
82 
83 }
84 
85 int vnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq, unsigned int index,
86 	unsigned int desc_count, unsigned int desc_size)
87 {
88 	int err;
89 
90 	wq->index = index;
91 	wq->vdev = vdev;
92 
93 	wq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_WQ, index);
94 	if (!wq->ctrl) {
95 		printk(KERN_ERR "Failed to hook WQ[%d] resource\n", index);
96 		return -EINVAL;
97 	}
98 
99 	vnic_wq_disable(wq);
100 
101 	err = vnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count, desc_size);
102 	if (err)
103 		return err;
104 
105 	err = vnic_wq_alloc_bufs(wq);
106 	if (err) {
107 		vnic_wq_free(wq);
108 		return err;
109 	}
110 
111 	return 0;
112 }
113 
114 void vnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
115 	unsigned int error_interrupt_enable,
116 	unsigned int error_interrupt_offset)
117 {
118 	u64 paddr;
119 
120 	paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
121 	writeq(paddr, &wq->ctrl->ring_base);
122 	iowrite32(wq->ring.desc_count, &wq->ctrl->ring_size);
123 	iowrite32(0, &wq->ctrl->fetch_index);
124 	iowrite32(0, &wq->ctrl->posted_index);
125 	iowrite32(cq_index, &wq->ctrl->cq_index);
126 	iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
127 	iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
128 	iowrite32(0, &wq->ctrl->error_status);
129 }
130 
131 unsigned int vnic_wq_error_status(struct vnic_wq *wq)
132 {
133 	return ioread32(&wq->ctrl->error_status);
134 }
135 
136 void vnic_wq_enable(struct vnic_wq *wq)
137 {
138 	iowrite32(1, &wq->ctrl->enable);
139 }
140 
141 int vnic_wq_disable(struct vnic_wq *wq)
142 {
143 	unsigned int wait;
144 
145 	iowrite32(0, &wq->ctrl->enable);
146 
147 	/* Wait for HW to ACK disable request */
148 	for (wait = 0; wait < 100; wait++) {
149 		if (!(ioread32(&wq->ctrl->running)))
150 			return 0;
151 		udelay(1);
152 	}
153 
154 	printk(KERN_ERR "Failed to disable WQ[%d]\n", wq->index);
155 
156 	return -ETIMEDOUT;
157 }
158 
159 void vnic_wq_clean(struct vnic_wq *wq,
160 	void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf))
161 {
162 	struct vnic_wq_buf *buf;
163 
164 	BUG_ON(ioread32(&wq->ctrl->enable));
165 
166 	buf = wq->to_clean;
167 
168 	while (vnic_wq_desc_used(wq) > 0) {
169 
170 		(*buf_clean)(wq, buf);
171 
172 		buf = wq->to_clean = buf->next;
173 		wq->ring.desc_avail++;
174 	}
175 
176 	wq->to_use = wq->to_clean = wq->bufs[0];
177 
178 	iowrite32(0, &wq->ctrl->fetch_index);
179 	iowrite32(0, &wq->ctrl->posted_index);
180 	iowrite32(0, &wq->ctrl->error_status);
181 
182 	vnic_dev_clear_desc_ring(&wq->ring);
183 }
184