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_rq.h"
29
30static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
31{
32	struct vnic_rq_buf *buf;
33	unsigned int i, j, count = rq->ring.desc_count;
34	unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
35
36	for (i = 0; i < blks; i++) {
37		rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ(count), GFP_ATOMIC);
38		if (!rq->bufs[i])
39			return -ENOMEM;
40	}
41
42	for (i = 0; i < blks; i++) {
43		buf = rq->bufs[i];
44		for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES(count); j++) {
45			buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES(count) + j;
46			buf->desc = (u8 *)rq->ring.descs +
47				rq->ring.desc_size * buf->index;
48			if (buf->index + 1 == count) {
49				buf->next = rq->bufs[0];
50				break;
51			} else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES(count)) {
52				buf->next = rq->bufs[i + 1];
53			} else {
54				buf->next = buf + 1;
55				buf++;
56			}
57		}
58	}
59
60	rq->to_use = rq->to_clean = rq->bufs[0];
61
62	return 0;
63}
64
65void vnic_rq_free(struct vnic_rq *rq)
66{
67	struct vnic_dev *vdev;
68	unsigned int i;
69
70	vdev = rq->vdev;
71
72	vnic_dev_free_desc_ring(vdev, &rq->ring);
73
74	for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
75		if (rq->bufs[i]) {
76			kfree(rq->bufs[i]);
77			rq->bufs[i] = NULL;
78		}
79	}
80
81	rq->ctrl = NULL;
82}
83
84int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
85	unsigned int desc_count, unsigned int desc_size)
86{
87	int err;
88
89	rq->index = index;
90	rq->vdev = vdev;
91
92	rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
93	if (!rq->ctrl) {
94		pr_err("Failed to hook RQ[%d] resource\n", index);
95		return -EINVAL;
96	}
97
98	vnic_rq_disable(rq);
99
100	err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
101	if (err)
102		return err;
103
104	err = vnic_rq_alloc_bufs(rq);
105	if (err) {
106		vnic_rq_free(rq);
107		return err;
108	}
109
110	return 0;
111}
112
113static void vnic_rq_init_start(struct vnic_rq *rq, unsigned int cq_index,
114	unsigned int fetch_index, unsigned int posted_index,
115	unsigned int error_interrupt_enable,
116	unsigned int error_interrupt_offset)
117{
118	u64 paddr;
119	unsigned int count = rq->ring.desc_count;
120
121	paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
122	writeq(paddr, &rq->ctrl->ring_base);
123	iowrite32(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	iowrite32(fetch_index, &rq->ctrl->fetch_index);
130	iowrite32(posted_index, &rq->ctrl->posted_index);
131
132	rq->to_use = rq->to_clean =
133		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
134			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
135}
136
137void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
138	unsigned int error_interrupt_enable,
139	unsigned int error_interrupt_offset)
140{
141	u32 fetch_index = 0;
142
143	/* Use current fetch_index as the ring starting point */
144	fetch_index = ioread32(&rq->ctrl->fetch_index);
145
146	if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
147		/* Hardware surprise removal: reset fetch_index */
148		fetch_index = 0;
149	}
150
151	vnic_rq_init_start(rq, cq_index,
152		fetch_index, fetch_index,
153		error_interrupt_enable,
154		error_interrupt_offset);
155}
156
157unsigned int vnic_rq_error_status(struct vnic_rq *rq)
158{
159	return ioread32(&rq->ctrl->error_status);
160}
161
162void vnic_rq_enable(struct vnic_rq *rq)
163{
164	iowrite32(1, &rq->ctrl->enable);
165}
166
167int vnic_rq_disable(struct vnic_rq *rq)
168{
169	unsigned int wait;
170
171	iowrite32(0, &rq->ctrl->enable);
172
173	/* Wait for HW to ACK disable request */
174	for (wait = 0; wait < 1000; wait++) {
175		if (!(ioread32(&rq->ctrl->running)))
176			return 0;
177		udelay(10);
178	}
179
180	pr_err("Failed to disable RQ[%d]\n", rq->index);
181
182	return -ETIMEDOUT;
183}
184
185void vnic_rq_clean(struct vnic_rq *rq,
186	void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
187{
188	struct vnic_rq_buf *buf;
189	u32 fetch_index;
190	unsigned int count = rq->ring.desc_count;
191	int i;
192
193	buf = rq->to_clean;
194
195	for (i = 0; i < rq->ring.desc_count; i++) {
196		(*buf_clean)(rq, buf);
197		buf = buf->next;
198	}
199	rq->ring.desc_avail = rq->ring.desc_count - 1;
200
201	/* Use current fetch_index as the ring starting point */
202	fetch_index = ioread32(&rq->ctrl->fetch_index);
203
204	if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
205		/* Hardware surprise removal: reset fetch_index */
206		fetch_index = 0;
207	}
208	rq->to_use = rq->to_clean =
209		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
210			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
211	iowrite32(fetch_index, &rq->ctrl->posted_index);
212
213	vnic_dev_clear_desc_ring(&rq->ring);
214}
215
216