xref: /openbmc/linux/drivers/scsi/fnic/vnic_rq.c (revision 9cfc5c90)
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_rq.h"
26 
27 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
28 {
29 	struct vnic_rq_buf *buf;
30 	struct vnic_dev *vdev;
31 	unsigned int i, j, count = rq->ring.desc_count;
32 	unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
33 
34 	vdev = rq->vdev;
35 
36 	for (i = 0; i < blks; i++) {
37 		rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
38 		if (!rq->bufs[i]) {
39 			printk(KERN_ERR "Failed to alloc rq_bufs\n");
40 			return -ENOMEM;
41 		}
42 	}
43 
44 	for (i = 0; i < blks; i++) {
45 		buf = rq->bufs[i];
46 		for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
47 			buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
48 			buf->desc = (u8 *)rq->ring.descs +
49 				rq->ring.desc_size * buf->index;
50 			if (buf->index + 1 == count) {
51 				buf->next = rq->bufs[0];
52 				break;
53 			} else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
54 				buf->next = rq->bufs[i + 1];
55 			} else {
56 				buf->next = buf + 1;
57 				buf++;
58 			}
59 		}
60 	}
61 
62 	rq->to_use = rq->to_clean = rq->bufs[0];
63 	rq->buf_index = 0;
64 
65 	return 0;
66 }
67 
68 void vnic_rq_free(struct vnic_rq *rq)
69 {
70 	struct vnic_dev *vdev;
71 	unsigned int i;
72 
73 	vdev = rq->vdev;
74 
75 	vnic_dev_free_desc_ring(vdev, &rq->ring);
76 
77 	for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
78 		kfree(rq->bufs[i]);
79 		rq->bufs[i] = NULL;
80 	}
81 
82 	rq->ctrl = NULL;
83 }
84 
85 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
86 	unsigned int desc_count, unsigned int desc_size)
87 {
88 	int err;
89 
90 	rq->index = index;
91 	rq->vdev = vdev;
92 
93 	rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
94 	if (!rq->ctrl) {
95 		printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
96 		return -EINVAL;
97 	}
98 
99 	vnic_rq_disable(rq);
100 
101 	err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
102 	if (err)
103 		return err;
104 
105 	err = vnic_rq_alloc_bufs(rq);
106 	if (err) {
107 		vnic_rq_free(rq);
108 		return err;
109 	}
110 
111 	return 0;
112 }
113 
114 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
115 	unsigned int error_interrupt_enable,
116 	unsigned int error_interrupt_offset)
117 {
118 	u64 paddr;
119 	u32 fetch_index;
120 
121 	paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
122 	writeq(paddr, &rq->ctrl->ring_base);
123 	iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
124 	iowrite32(cq_index, &rq->ctrl->cq_index);
125 	iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
126 	iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
127 	iowrite32(0, &rq->ctrl->dropped_packet_count);
128 	iowrite32(0, &rq->ctrl->error_status);
129 
130 	/* Use current fetch_index as the ring starting point */
131 	fetch_index = ioread32(&rq->ctrl->fetch_index);
132 	rq->to_use = rq->to_clean =
133 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
134 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
135 	iowrite32(fetch_index, &rq->ctrl->posted_index);
136 
137 	rq->buf_index = 0;
138 }
139 
140 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
141 {
142 	return ioread32(&rq->ctrl->error_status);
143 }
144 
145 void vnic_rq_enable(struct vnic_rq *rq)
146 {
147 	iowrite32(1, &rq->ctrl->enable);
148 }
149 
150 int vnic_rq_disable(struct vnic_rq *rq)
151 {
152 	unsigned int wait;
153 
154 	iowrite32(0, &rq->ctrl->enable);
155 
156 	/* Wait for HW to ACK disable request */
157 	for (wait = 0; wait < 100; wait++) {
158 		if (!(ioread32(&rq->ctrl->running)))
159 			return 0;
160 		udelay(1);
161 	}
162 
163 	printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
164 
165 	return -ETIMEDOUT;
166 }
167 
168 void vnic_rq_clean(struct vnic_rq *rq,
169 	void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
170 {
171 	struct vnic_rq_buf *buf;
172 	u32 fetch_index;
173 
174 	BUG_ON(ioread32(&rq->ctrl->enable));
175 
176 	buf = rq->to_clean;
177 
178 	while (vnic_rq_desc_used(rq) > 0) {
179 
180 		(*buf_clean)(rq, buf);
181 
182 		buf = rq->to_clean = buf->next;
183 		rq->ring.desc_avail++;
184 	}
185 
186 	/* Use current fetch_index as the ring starting point */
187 	fetch_index = ioread32(&rq->ctrl->fetch_index);
188 	rq->to_use = rq->to_clean =
189 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
190 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
191 	iowrite32(fetch_index, &rq->ctrl->posted_index);
192 
193 	rq->buf_index = 0;
194 
195 	vnic_dev_clear_desc_ring(&rq->ring);
196 }
197 
198