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
26static 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
36static 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
43static 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
81void 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
99int 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
123int 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
154void 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
177void 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
185unsigned int svnic_wq_error_status(struct vnic_wq *wq)
186{
187	return ioread32(&wq->ctrl->error_status);
188}
189
190void svnic_wq_enable(struct vnic_wq *wq)
191{
192	iowrite32(1, &wq->ctrl->enable);
193}
194
195int 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
213void 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