xref: /openbmc/linux/drivers/scsi/snic/vnic_wq.c (revision 842ed298)
1 /*
2  * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
3  *
4  * This program is free software; you may redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; version 2 of the License.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
9  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
10  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
11  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
12  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
13  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
14  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
15  * SOFTWARE.
16  */
17 
18 #include <linux/errno.h>
19 #include <linux/types.h>
20 #include <linux/pci.h>
21 #include <linux/delay.h>
22 #include <linux/slab.h>
23 #include "vnic_dev.h"
24 #include "vnic_wq.h"
25 
26 static inline int vnic_wq_get_ctrl(struct vnic_dev *vdev, struct vnic_wq *wq,
27 	unsigned int index, enum vnic_res_type res_type)
28 {
29 	wq->ctrl = svnic_dev_get_res(vdev, res_type, index);
30 	if (!wq->ctrl)
31 		return -EINVAL;
32 
33 	return 0;
34 }
35 
36 static inline int vnic_wq_alloc_ring(struct vnic_dev *vdev, struct vnic_wq *wq,
37 	unsigned int index, unsigned int desc_count, unsigned int desc_size)
38 {
39 	return svnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count,
40 					 desc_size);
41 }
42 
43 static int vnic_wq_alloc_bufs(struct vnic_wq *wq)
44 {
45 	struct vnic_wq_buf *buf;
46 	unsigned int i, j, count = wq->ring.desc_count;
47 	unsigned int blks = VNIC_WQ_BUF_BLKS_NEEDED(count);
48 
49 	for (i = 0; i < blks; i++) {
50 		wq->bufs[i] = kzalloc(VNIC_WQ_BUF_BLK_SZ, GFP_ATOMIC);
51 		if (!wq->bufs[i]) {
52 			pr_err("Failed to alloc wq_bufs\n");
53 
54 			return -ENOMEM;
55 		}
56 	}
57 
58 	for (i = 0; i < blks; i++) {
59 		buf = wq->bufs[i];
60 		for (j = 0; j < VNIC_WQ_BUF_DFLT_BLK_ENTRIES; j++) {
61 			buf->index = i * VNIC_WQ_BUF_DFLT_BLK_ENTRIES + j;
62 			buf->desc = (u8 *)wq->ring.descs +
63 				wq->ring.desc_size * buf->index;
64 			if (buf->index + 1 == count) {
65 				buf->next = wq->bufs[0];
66 				break;
67 			} else if (j + 1 == VNIC_WQ_BUF_DFLT_BLK_ENTRIES) {
68 				buf->next = wq->bufs[i + 1];
69 			} else {
70 				buf->next = buf + 1;
71 				buf++;
72 			}
73 		}
74 	}
75 
76 	wq->to_use = wq->to_clean = wq->bufs[0];
77 
78 	return 0;
79 }
80 
81 void svnic_wq_free(struct vnic_wq *wq)
82 {
83 	struct vnic_dev *vdev;
84 	unsigned int i;
85 
86 	vdev = wq->vdev;
87 
88 	svnic_dev_free_desc_ring(vdev, &wq->ring);
89 
90 	for (i = 0; i < VNIC_WQ_BUF_BLKS_MAX; i++) {
91 		kfree(wq->bufs[i]);
92 		wq->bufs[i] = NULL;
93 	}
94 
95 	wq->ctrl = NULL;
96 
97 }
98 
99 int vnic_wq_devcmd2_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
100 	unsigned int desc_count, unsigned int desc_size)
101 {
102 	int err;
103 
104 	wq->index = 0;
105 	wq->vdev = vdev;
106 
107 	err = vnic_wq_get_ctrl(vdev, wq, 0, RES_TYPE_DEVCMD2);
108 	if (err) {
109 		pr_err("Failed to get devcmd2 resource\n");
110 
111 		return err;
112 	}
113 
114 	svnic_wq_disable(wq);
115 
116 	err = vnic_wq_alloc_ring(vdev, wq, 0, desc_count, desc_size);
117 	if (err)
118 		return err;
119 
120 	return 0;
121 }
122 
123 int svnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
124 	unsigned int index, unsigned int desc_count, unsigned int desc_size)
125 {
126 	int err;
127 
128 	wq->index = index;
129 	wq->vdev = vdev;
130 
131 	err = vnic_wq_get_ctrl(vdev, wq, index, RES_TYPE_WQ);
132 	if (err) {
133 		pr_err("Failed to hook WQ[%d] resource\n", index);
134 
135 		return err;
136 	}
137 
138 	svnic_wq_disable(wq);
139 
140 	err = vnic_wq_alloc_ring(vdev, wq, index, desc_count, desc_size);
141 	if (err)
142 		return err;
143 
144 	err = vnic_wq_alloc_bufs(wq);
145 	if (err) {
146 		svnic_wq_free(wq);
147 
148 		return err;
149 	}
150 
151 	return 0;
152 }
153 
154 void vnic_wq_init_start(struct vnic_wq *wq, unsigned int cq_index,
155 	unsigned int fetch_index, unsigned int posted_index,
156 	unsigned int error_interrupt_enable,
157 	unsigned int error_interrupt_offset)
158 {
159 	u64 paddr;
160 	unsigned int count = wq->ring.desc_count;
161 
162 	paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
163 	writeq(paddr, &wq->ctrl->ring_base);
164 	iowrite32(count, &wq->ctrl->ring_size);
165 	iowrite32(fetch_index, &wq->ctrl->fetch_index);
166 	iowrite32(posted_index, &wq->ctrl->posted_index);
167 	iowrite32(cq_index, &wq->ctrl->cq_index);
168 	iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
169 	iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
170 	iowrite32(0, &wq->ctrl->error_status);
171 
172 	wq->to_use = wq->to_clean =
173 		&wq->bufs[fetch_index / VNIC_WQ_BUF_BLK_ENTRIES(count)]
174 			[fetch_index % VNIC_WQ_BUF_BLK_ENTRIES(count)];
175 }
176 
177 void svnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
178 	unsigned int error_interrupt_enable,
179 	unsigned int error_interrupt_offset)
180 {
181 	vnic_wq_init_start(wq, cq_index, 0, 0, error_interrupt_enable,
182 			   error_interrupt_offset);
183 }
184 
185 unsigned int svnic_wq_error_status(struct vnic_wq *wq)
186 {
187 	return ioread32(&wq->ctrl->error_status);
188 }
189 
190 void svnic_wq_enable(struct vnic_wq *wq)
191 {
192 	iowrite32(1, &wq->ctrl->enable);
193 }
194 
195 int svnic_wq_disable(struct vnic_wq *wq)
196 {
197 	unsigned int wait;
198 
199 	iowrite32(0, &wq->ctrl->enable);
200 
201 	/* Wait for HW to ACK disable request */
202 	for (wait = 0; wait < 100; wait++) {
203 		if (!(ioread32(&wq->ctrl->running)))
204 			return 0;
205 		udelay(1);
206 	}
207 
208 	pr_err("Failed to disable WQ[%d]\n", wq->index);
209 
210 	return -ETIMEDOUT;
211 }
212 
213 void svnic_wq_clean(struct vnic_wq *wq,
214 	void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf))
215 {
216 	struct vnic_wq_buf *buf;
217 
218 	BUG_ON(ioread32(&wq->ctrl->enable));
219 
220 	buf = wq->to_clean;
221 
222 	while (svnic_wq_desc_used(wq) > 0) {
223 
224 		(*buf_clean)(wq, buf);
225 
226 		buf = wq->to_clean = buf->next;
227 		wq->ring.desc_avail++;
228 	}
229 
230 	wq->to_use = wq->to_clean = wq->bufs[0];
231 
232 	iowrite32(0, &wq->ctrl->fetch_index);
233 	iowrite32(0, &wq->ctrl->posted_index);
234 	iowrite32(0, &wq->ctrl->error_status);
235 
236 	svnic_dev_clear_desc_ring(&wq->ring);
237 }
238