xref: /openbmc/linux/drivers/scsi/fnic/vnic_wq.c (revision 78c99ba1)
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_wq.h"
25 
26 static int vnic_wq_alloc_bufs(struct vnic_wq *wq)
27 {
28 	struct vnic_wq_buf *buf;
29 	struct vnic_dev *vdev;
30 	unsigned int i, j, count = wq->ring.desc_count;
31 	unsigned int blks = VNIC_WQ_BUF_BLKS_NEEDED(count);
32 
33 	vdev = wq->vdev;
34 
35 	for (i = 0; i < blks; i++) {
36 		wq->bufs[i] = kzalloc(VNIC_WQ_BUF_BLK_SZ, GFP_ATOMIC);
37 		if (!wq->bufs[i]) {
38 			printk(KERN_ERR "Failed to alloc wq_bufs\n");
39 			return -ENOMEM;
40 		}
41 	}
42 
43 	for (i = 0; i < blks; i++) {
44 		buf = wq->bufs[i];
45 		for (j = 0; j < VNIC_WQ_BUF_BLK_ENTRIES; j++) {
46 			buf->index = i * VNIC_WQ_BUF_BLK_ENTRIES + j;
47 			buf->desc = (u8 *)wq->ring.descs +
48 				wq->ring.desc_size * buf->index;
49 			if (buf->index + 1 == count) {
50 				buf->next = wq->bufs[0];
51 				break;
52 			} else if (j + 1 == VNIC_WQ_BUF_BLK_ENTRIES) {
53 				buf->next = wq->bufs[i + 1];
54 			} else {
55 				buf->next = buf + 1;
56 				buf++;
57 			}
58 		}
59 	}
60 
61 	wq->to_use = wq->to_clean = wq->bufs[0];
62 
63 	return 0;
64 }
65 
66 void vnic_wq_free(struct vnic_wq *wq)
67 {
68 	struct vnic_dev *vdev;
69 	unsigned int i;
70 
71 	vdev = wq->vdev;
72 
73 	vnic_dev_free_desc_ring(vdev, &wq->ring);
74 
75 	for (i = 0; i < VNIC_WQ_BUF_BLKS_MAX; i++) {
76 		kfree(wq->bufs[i]);
77 		wq->bufs[i] = NULL;
78 	}
79 
80 	wq->ctrl = NULL;
81 
82 }
83 
84 int vnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq, unsigned int index,
85 	unsigned int desc_count, unsigned int desc_size)
86 {
87 	int err;
88 
89 	wq->index = index;
90 	wq->vdev = vdev;
91 
92 	wq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_WQ, index);
93 	if (!wq->ctrl) {
94 		printk(KERN_ERR "Failed to hook WQ[%d] resource\n", index);
95 		return -EINVAL;
96 	}
97 
98 	vnic_wq_disable(wq);
99 
100 	err = vnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count, desc_size);
101 	if (err)
102 		return err;
103 
104 	err = vnic_wq_alloc_bufs(wq);
105 	if (err) {
106 		vnic_wq_free(wq);
107 		return err;
108 	}
109 
110 	return 0;
111 }
112 
113 void vnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
114 	unsigned int error_interrupt_enable,
115 	unsigned int error_interrupt_offset)
116 {
117 	u64 paddr;
118 
119 	paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
120 	writeq(paddr, &wq->ctrl->ring_base);
121 	iowrite32(wq->ring.desc_count, &wq->ctrl->ring_size);
122 	iowrite32(0, &wq->ctrl->fetch_index);
123 	iowrite32(0, &wq->ctrl->posted_index);
124 	iowrite32(cq_index, &wq->ctrl->cq_index);
125 	iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
126 	iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
127 	iowrite32(0, &wq->ctrl->error_status);
128 }
129 
130 unsigned int vnic_wq_error_status(struct vnic_wq *wq)
131 {
132 	return ioread32(&wq->ctrl->error_status);
133 }
134 
135 void vnic_wq_enable(struct vnic_wq *wq)
136 {
137 	iowrite32(1, &wq->ctrl->enable);
138 }
139 
140 int vnic_wq_disable(struct vnic_wq *wq)
141 {
142 	unsigned int wait;
143 
144 	iowrite32(0, &wq->ctrl->enable);
145 
146 	/* Wait for HW to ACK disable request */
147 	for (wait = 0; wait < 100; wait++) {
148 		if (!(ioread32(&wq->ctrl->running)))
149 			return 0;
150 		udelay(1);
151 	}
152 
153 	printk(KERN_ERR "Failed to disable WQ[%d]\n", wq->index);
154 
155 	return -ETIMEDOUT;
156 }
157 
158 void vnic_wq_clean(struct vnic_wq *wq,
159 	void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf))
160 {
161 	struct vnic_wq_buf *buf;
162 
163 	BUG_ON(ioread32(&wq->ctrl->enable));
164 
165 	buf = wq->to_clean;
166 
167 	while (vnic_wq_desc_used(wq) > 0) {
168 
169 		(*buf_clean)(wq, buf);
170 
171 		buf = wq->to_clean = buf->next;
172 		wq->ring.desc_avail++;
173 	}
174 
175 	wq->to_use = wq->to_clean = wq->bufs[0];
176 
177 	iowrite32(0, &wq->ctrl->fetch_index);
178 	iowrite32(0, &wq->ctrl->posted_index);
179 	iowrite32(0, &wq->ctrl->error_status);
180 
181 	vnic_dev_clear_desc_ring(&wq->ring);
182 }
183