1 /*
2  * Copyright 2008-2010 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 
20 #include <linux/kernel.h>
21 #include <linux/errno.h>
22 #include <linux/types.h>
23 #include <linux/pci.h>
24 #include <linux/delay.h>
25 #include <linux/slab.h>
26 
27 #include "vnic_dev.h"
28 #include "vnic_wq.h"
29 #include "enic.h"
30 
31 static int vnic_wq_alloc_bufs(struct vnic_wq *wq)
32 {
33 	struct vnic_wq_buf *buf;
34 	unsigned int i, j, count = wq->ring.desc_count;
35 	unsigned int blks = VNIC_WQ_BUF_BLKS_NEEDED(count);
36 
37 	for (i = 0; i < blks; i++) {
38 		wq->bufs[i] = kzalloc(VNIC_WQ_BUF_BLK_SZ(count), GFP_ATOMIC);
39 		if (!wq->bufs[i])
40 			return -ENOMEM;
41 	}
42 
43 	for (i = 0; i < blks; i++) {
44 		buf = wq->bufs[i];
45 		for (j = 0; j < VNIC_WQ_BUF_BLK_ENTRIES(count); j++) {
46 			buf->index = i * VNIC_WQ_BUF_BLK_ENTRIES(count) + 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 				buf->next->prev = buf;
52 				break;
53 			} else if (j + 1 == VNIC_WQ_BUF_BLK_ENTRIES(count)) {
54 				buf->next = wq->bufs[i + 1];
55 				buf->next->prev = buf;
56 			} else {
57 				buf->next = buf + 1;
58 				buf->next->prev = buf;
59 				buf++;
60 			}
61 		}
62 	}
63 
64 	wq->to_use = wq->to_clean = wq->bufs[0];
65 
66 	return 0;
67 }
68 
69 void vnic_wq_free(struct vnic_wq *wq)
70 {
71 	struct vnic_dev *vdev;
72 	unsigned int i;
73 
74 	vdev = wq->vdev;
75 
76 	vnic_dev_free_desc_ring(vdev, &wq->ring);
77 
78 	for (i = 0; i < VNIC_WQ_BUF_BLKS_MAX; i++) {
79 		if (wq->bufs[i]) {
80 			kfree(wq->bufs[i]);
81 			wq->bufs[i] = NULL;
82 		}
83 	}
84 
85 	wq->ctrl = NULL;
86 }
87 
88 int vnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq, unsigned int index,
89 	unsigned int desc_count, unsigned int desc_size)
90 {
91 	int err;
92 
93 	wq->index = index;
94 	wq->vdev = vdev;
95 
96 	wq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_WQ, index);
97 	if (!wq->ctrl) {
98 		vdev_err("Failed to hook WQ[%d] resource\n", index);
99 		return -EINVAL;
100 	}
101 
102 	vnic_wq_disable(wq);
103 
104 	err = vnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count, desc_size);
105 	if (err)
106 		return err;
107 
108 	err = vnic_wq_alloc_bufs(wq);
109 	if (err) {
110 		vnic_wq_free(wq);
111 		return err;
112 	}
113 
114 	return 0;
115 }
116 
117 int enic_wq_devcmd2_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
118 			  unsigned int desc_count, unsigned int desc_size)
119 {
120 	int err;
121 
122 	wq->index = 0;
123 	wq->vdev = vdev;
124 
125 	wq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_DEVCMD2, 0);
126 	if (!wq->ctrl)
127 		return -EINVAL;
128 	vnic_wq_disable(wq);
129 	err = vnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count, desc_size);
130 
131 	return err;
132 }
133 
134 void enic_wq_init_start(struct vnic_wq *wq, unsigned int cq_index,
135 			unsigned int fetch_index, unsigned int posted_index,
136 			unsigned int error_interrupt_enable,
137 			unsigned int error_interrupt_offset)
138 {
139 	u64 paddr;
140 	unsigned int count = wq->ring.desc_count;
141 
142 	paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
143 	writeq(paddr, &wq->ctrl->ring_base);
144 	iowrite32(count, &wq->ctrl->ring_size);
145 	iowrite32(fetch_index, &wq->ctrl->fetch_index);
146 	iowrite32(posted_index, &wq->ctrl->posted_index);
147 	iowrite32(cq_index, &wq->ctrl->cq_index);
148 	iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
149 	iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
150 	iowrite32(0, &wq->ctrl->error_status);
151 
152 	wq->to_use = wq->to_clean =
153 		&wq->bufs[fetch_index / VNIC_WQ_BUF_BLK_ENTRIES(count)]
154 			[fetch_index % VNIC_WQ_BUF_BLK_ENTRIES(count)];
155 }
156 
157 void vnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
158 	unsigned int error_interrupt_enable,
159 	unsigned int error_interrupt_offset)
160 {
161 	enic_wq_init_start(wq, cq_index, 0, 0,
162 		error_interrupt_enable,
163 		error_interrupt_offset);
164 }
165 
166 unsigned int vnic_wq_error_status(struct vnic_wq *wq)
167 {
168 	return ioread32(&wq->ctrl->error_status);
169 }
170 
171 void vnic_wq_enable(struct vnic_wq *wq)
172 {
173 	iowrite32(1, &wq->ctrl->enable);
174 }
175 
176 int vnic_wq_disable(struct vnic_wq *wq)
177 {
178 	unsigned int wait;
179 	struct vnic_dev *vdev = wq->vdev;
180 
181 	iowrite32(0, &wq->ctrl->enable);
182 
183 	/* Wait for HW to ACK disable request */
184 	for (wait = 0; wait < 1000; wait++) {
185 		if (!(ioread32(&wq->ctrl->running)))
186 			return 0;
187 		udelay(10);
188 	}
189 
190 	vdev_neterr("Failed to disable WQ[%d]\n", wq->index);
191 
192 	return -ETIMEDOUT;
193 }
194 
195 void vnic_wq_clean(struct vnic_wq *wq,
196 	void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf))
197 {
198 	struct vnic_wq_buf *buf;
199 
200 	buf = wq->to_clean;
201 
202 	while (vnic_wq_desc_used(wq) > 0) {
203 
204 		(*buf_clean)(wq, buf);
205 
206 		buf = wq->to_clean = buf->next;
207 		wq->ring.desc_avail++;
208 	}
209 
210 	wq->to_use = wq->to_clean = wq->bufs[0];
211 
212 	iowrite32(0, &wq->ctrl->fetch_index);
213 	iowrite32(0, &wq->ctrl->posted_index);
214 	iowrite32(0, &wq->ctrl->error_status);
215 
216 	vnic_dev_clear_desc_ring(&wq->ring);
217 }
218