xref: /linux/drivers/net/ethernet/cisco/enic/vnic_rq.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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 
30 static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
31 {
32 	struct vnic_rq_buf *buf;
33 	struct vnic_dev *vdev;
34 	unsigned int i, j, count = rq->ring.desc_count;
35 	unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
36 
37 	vdev = rq->vdev;
38 
39 	for (i = 0; i < blks; i++) {
40 		rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ(count), GFP_ATOMIC);
41 		if (!rq->bufs[i]) {
42 			pr_err("Failed to alloc rq_bufs\n");
43 			return -ENOMEM;
44 		}
45 	}
46 
47 	for (i = 0; i < blks; i++) {
48 		buf = rq->bufs[i];
49 		for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES(count); j++) {
50 			buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES(count) + j;
51 			buf->desc = (u8 *)rq->ring.descs +
52 				rq->ring.desc_size * buf->index;
53 			if (buf->index + 1 == count) {
54 				buf->next = rq->bufs[0];
55 				break;
56 			} else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES(count)) {
57 				buf->next = rq->bufs[i + 1];
58 			} else {
59 				buf->next = buf + 1;
60 				buf++;
61 			}
62 		}
63 	}
64 
65 	rq->to_use = rq->to_clean = rq->bufs[0];
66 
67 	return 0;
68 }
69 
70 void vnic_rq_free(struct vnic_rq *rq)
71 {
72 	struct vnic_dev *vdev;
73 	unsigned int i;
74 
75 	vdev = rq->vdev;
76 
77 	vnic_dev_free_desc_ring(vdev, &rq->ring);
78 
79 	for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
80 		if (rq->bufs[i]) {
81 			kfree(rq->bufs[i]);
82 			rq->bufs[i] = NULL;
83 		}
84 	}
85 
86 	rq->ctrl = NULL;
87 }
88 
89 int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
90 	unsigned int desc_count, unsigned int desc_size)
91 {
92 	int err;
93 
94 	rq->index = index;
95 	rq->vdev = vdev;
96 
97 	rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
98 	if (!rq->ctrl) {
99 		pr_err("Failed to hook RQ[%d] resource\n", index);
100 		return -EINVAL;
101 	}
102 
103 	vnic_rq_disable(rq);
104 
105 	err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
106 	if (err)
107 		return err;
108 
109 	err = vnic_rq_alloc_bufs(rq);
110 	if (err) {
111 		vnic_rq_free(rq);
112 		return err;
113 	}
114 
115 	return 0;
116 }
117 
118 static void vnic_rq_init_start(struct vnic_rq *rq, unsigned int cq_index,
119 	unsigned int fetch_index, unsigned int posted_index,
120 	unsigned int error_interrupt_enable,
121 	unsigned int error_interrupt_offset)
122 {
123 	u64 paddr;
124 	unsigned int count = rq->ring.desc_count;
125 
126 	paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
127 	writeq(paddr, &rq->ctrl->ring_base);
128 	iowrite32(count, &rq->ctrl->ring_size);
129 	iowrite32(cq_index, &rq->ctrl->cq_index);
130 	iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
131 	iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
132 	iowrite32(0, &rq->ctrl->dropped_packet_count);
133 	iowrite32(0, &rq->ctrl->error_status);
134 	iowrite32(fetch_index, &rq->ctrl->fetch_index);
135 	iowrite32(posted_index, &rq->ctrl->posted_index);
136 
137 	rq->to_use = rq->to_clean =
138 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
139 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
140 }
141 
142 void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
143 	unsigned int error_interrupt_enable,
144 	unsigned int error_interrupt_offset)
145 {
146 	u32 fetch_index;
147 
148 	/* Use current fetch_index as the ring starting point */
149 	fetch_index = ioread32(&rq->ctrl->fetch_index);
150 
151 	if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
152 		/* Hardware surprise removal: reset fetch_index */
153 		fetch_index = 0;
154 	}
155 
156 	vnic_rq_init_start(rq, cq_index,
157 		fetch_index, fetch_index,
158 		error_interrupt_enable,
159 		error_interrupt_offset);
160 }
161 
162 unsigned int vnic_rq_error_status(struct vnic_rq *rq)
163 {
164 	return ioread32(&rq->ctrl->error_status);
165 }
166 
167 void vnic_rq_enable(struct vnic_rq *rq)
168 {
169 	iowrite32(1, &rq->ctrl->enable);
170 }
171 
172 int vnic_rq_disable(struct vnic_rq *rq)
173 {
174 	unsigned int wait;
175 
176 	iowrite32(0, &rq->ctrl->enable);
177 
178 	/* Wait for HW to ACK disable request */
179 	for (wait = 0; wait < 1000; wait++) {
180 		if (!(ioread32(&rq->ctrl->running)))
181 			return 0;
182 		udelay(10);
183 	}
184 
185 	pr_err("Failed to disable RQ[%d]\n", rq->index);
186 
187 	return -ETIMEDOUT;
188 }
189 
190 void vnic_rq_clean(struct vnic_rq *rq,
191 	void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
192 {
193 	struct vnic_rq_buf *buf;
194 	u32 fetch_index;
195 	unsigned int count = rq->ring.desc_count;
196 
197 	buf = rq->to_clean;
198 
199 	while (vnic_rq_desc_used(rq) > 0) {
200 
201 		(*buf_clean)(rq, buf);
202 
203 		buf = rq->to_clean = buf->next;
204 		rq->ring.desc_avail++;
205 	}
206 
207 	/* Use current fetch_index as the ring starting point */
208 	fetch_index = ioread32(&rq->ctrl->fetch_index);
209 
210 	if (fetch_index == 0xFFFFFFFF) { /* check for hardware gone  */
211 		/* Hardware surprise removal: reset fetch_index */
212 		fetch_index = 0;
213 	}
214 	rq->to_use = rq->to_clean =
215 		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES(count)]
216 			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES(count)];
217 	iowrite32(fetch_index, &rq->ctrl->posted_index);
218 
219 	vnic_dev_clear_desc_ring(&rq->ring);
220 }
221 
222