xref: /openbmc/linux/drivers/scsi/fnic/vnic_wq.c (revision 39f555fb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
4  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
5  */
6 
7 #include <linux/errno.h>
8 #include <linux/types.h>
9 #include <linux/pci.h>
10 #include <linux/delay.h>
11 #include <linux/slab.h>
12 #include "vnic_dev.h"
13 #include "vnic_wq.h"
14 
15 
16 static int vnic_wq_get_ctrl(struct vnic_dev *vdev, struct vnic_wq *wq,
17 		unsigned int index, enum vnic_res_type res_type)
18 {
19 	wq->ctrl = vnic_dev_get_res(vdev, res_type, index);
20 
21 	if (!wq->ctrl)
22 		return -EINVAL;
23 
24 	return 0;
25 }
26 
27 
28 static int vnic_wq_alloc_ring(struct vnic_dev *vdev, struct vnic_wq *wq,
29 		unsigned int desc_count, unsigned int desc_size)
30 {
31 	return vnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count, desc_size);
32 }
33 
34 
35 static int vnic_wq_alloc_bufs(struct vnic_wq *wq)
36 {
37 	struct vnic_wq_buf *buf;
38 	unsigned int i, j, count = wq->ring.desc_count;
39 	unsigned int blks = VNIC_WQ_BUF_BLKS_NEEDED(count);
40 
41 	for (i = 0; i < blks; i++) {
42 		wq->bufs[i] = kzalloc(VNIC_WQ_BUF_BLK_SZ, GFP_ATOMIC);
43 		if (!wq->bufs[i]) {
44 			printk(KERN_ERR "Failed to alloc wq_bufs\n");
45 			return -ENOMEM;
46 		}
47 	}
48 
49 	for (i = 0; i < blks; i++) {
50 		buf = wq->bufs[i];
51 		for (j = 0; j < VNIC_WQ_BUF_BLK_ENTRIES; j++) {
52 			buf->index = i * VNIC_WQ_BUF_BLK_ENTRIES + j;
53 			buf->desc = (u8 *)wq->ring.descs +
54 				wq->ring.desc_size * buf->index;
55 			if (buf->index + 1 == count) {
56 				buf->next = wq->bufs[0];
57 				break;
58 			} else if (j + 1 == VNIC_WQ_BUF_BLK_ENTRIES) {
59 				buf->next = wq->bufs[i + 1];
60 			} else {
61 				buf->next = buf + 1;
62 				buf++;
63 			}
64 		}
65 	}
66 
67 	wq->to_use = wq->to_clean = wq->bufs[0];
68 
69 	return 0;
70 }
71 
72 void vnic_wq_free(struct vnic_wq *wq)
73 {
74 	struct vnic_dev *vdev;
75 	unsigned int i;
76 
77 	vdev = wq->vdev;
78 
79 	vnic_dev_free_desc_ring(vdev, &wq->ring);
80 
81 	for (i = 0; i < VNIC_WQ_BUF_BLKS_MAX; i++) {
82 		kfree(wq->bufs[i]);
83 		wq->bufs[i] = NULL;
84 	}
85 
86 	wq->ctrl = NULL;
87 
88 }
89 
90 int vnic_wq_alloc(struct vnic_dev *vdev, struct vnic_wq *wq, unsigned int index,
91 	unsigned int desc_count, unsigned int desc_size)
92 {
93 	int err;
94 
95 	wq->index = index;
96 	wq->vdev = vdev;
97 
98 	wq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_WQ, index);
99 	if (!wq->ctrl) {
100 		printk(KERN_ERR "Failed to hook WQ[%d] resource\n", index);
101 		return -EINVAL;
102 	}
103 
104 	vnic_wq_disable(wq);
105 
106 	err = vnic_dev_alloc_desc_ring(vdev, &wq->ring, desc_count, desc_size);
107 	if (err)
108 		return err;
109 
110 	err = vnic_wq_alloc_bufs(wq);
111 	if (err) {
112 		vnic_wq_free(wq);
113 		return err;
114 	}
115 
116 	return 0;
117 }
118 
119 
120 int vnic_wq_devcmd2_alloc(struct vnic_dev *vdev, struct vnic_wq *wq,
121 		unsigned int desc_count, unsigned int desc_size)
122 {
123 	int err;
124 
125 	wq->index = 0;
126 	wq->vdev = vdev;
127 
128 	err = vnic_wq_get_ctrl(vdev, wq, 0, RES_TYPE_DEVCMD2);
129 	if (err) {
130 		pr_err("Failed to get devcmd2 resource\n");
131 		return err;
132 	}
133 	vnic_wq_disable(wq);
134 
135 	err = vnic_wq_alloc_ring(vdev, wq, desc_count, desc_size);
136 	if (err)
137 		return err;
138 	return 0;
139 }
140 
141 void vnic_wq_init_start(struct vnic_wq *wq, unsigned int cq_index,
142 		unsigned int fetch_index, unsigned int posted_index,
143 		unsigned int error_interrupt_enable,
144 		unsigned int error_interrupt_offset)
145 {
146 	u64 paddr;
147 	unsigned int count = wq->ring.desc_count;
148 
149 	paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
150 	writeq(paddr, &wq->ctrl->ring_base);
151 	iowrite32(count, &wq->ctrl->ring_size);
152 	iowrite32(fetch_index, &wq->ctrl->fetch_index);
153 	iowrite32(posted_index, &wq->ctrl->posted_index);
154 	iowrite32(cq_index, &wq->ctrl->cq_index);
155 	iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
156 	iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
157 	iowrite32(0, &wq->ctrl->error_status);
158 
159 	wq->to_use = wq->to_clean =
160 		&wq->bufs[fetch_index / VNIC_WQ_BUF_BLK_ENTRIES]
161 		[fetch_index % VNIC_WQ_BUF_BLK_ENTRIES];
162 }
163 
164 
165 void vnic_wq_init(struct vnic_wq *wq, unsigned int cq_index,
166 	unsigned int error_interrupt_enable,
167 	unsigned int error_interrupt_offset)
168 {
169 	u64 paddr;
170 
171 	paddr = (u64)wq->ring.base_addr | VNIC_PADDR_TARGET;
172 	writeq(paddr, &wq->ctrl->ring_base);
173 	iowrite32(wq->ring.desc_count, &wq->ctrl->ring_size);
174 	iowrite32(0, &wq->ctrl->fetch_index);
175 	iowrite32(0, &wq->ctrl->posted_index);
176 	iowrite32(cq_index, &wq->ctrl->cq_index);
177 	iowrite32(error_interrupt_enable, &wq->ctrl->error_interrupt_enable);
178 	iowrite32(error_interrupt_offset, &wq->ctrl->error_interrupt_offset);
179 	iowrite32(0, &wq->ctrl->error_status);
180 }
181 
182 unsigned int vnic_wq_error_status(struct vnic_wq *wq)
183 {
184 	return ioread32(&wq->ctrl->error_status);
185 }
186 
187 void vnic_wq_enable(struct vnic_wq *wq)
188 {
189 	iowrite32(1, &wq->ctrl->enable);
190 }
191 
192 int vnic_wq_disable(struct vnic_wq *wq)
193 {
194 	unsigned int wait;
195 
196 	iowrite32(0, &wq->ctrl->enable);
197 
198 	/* Wait for HW to ACK disable request */
199 	for (wait = 0; wait < 100; wait++) {
200 		if (!(ioread32(&wq->ctrl->running)))
201 			return 0;
202 		udelay(1);
203 	}
204 
205 	printk(KERN_ERR "Failed to disable WQ[%d]\n", wq->index);
206 
207 	return -ETIMEDOUT;
208 }
209 
210 void vnic_wq_clean(struct vnic_wq *wq,
211 	void (*buf_clean)(struct vnic_wq *wq, struct vnic_wq_buf *buf))
212 {
213 	struct vnic_wq_buf *buf;
214 
215 	BUG_ON(ioread32(&wq->ctrl->enable));
216 
217 	buf = wq->to_clean;
218 
219 	while (vnic_wq_desc_used(wq) > 0) {
220 
221 		(*buf_clean)(wq, buf);
222 
223 		buf = wq->to_clean = buf->next;
224 		wq->ring.desc_avail++;
225 	}
226 
227 	wq->to_use = wq->to_clean = wq->bufs[0];
228 
229 	iowrite32(0, &wq->ctrl->fetch_index);
230 	iowrite32(0, &wq->ctrl->posted_index);
231 	iowrite32(0, &wq->ctrl->error_status);
232 
233 	vnic_dev_clear_desc_ring(&wq->ring);
234 }
235