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_rq.h"
14
15static int vnic_rq_alloc_bufs(struct vnic_rq *rq)
16{
17	struct vnic_rq_buf *buf;
18	unsigned int i, j, count = rq->ring.desc_count;
19	unsigned int blks = VNIC_RQ_BUF_BLKS_NEEDED(count);
20
21	for (i = 0; i < blks; i++) {
22		rq->bufs[i] = kzalloc(VNIC_RQ_BUF_BLK_SZ, GFP_ATOMIC);
23		if (!rq->bufs[i]) {
24			printk(KERN_ERR "Failed to alloc rq_bufs\n");
25			return -ENOMEM;
26		}
27	}
28
29	for (i = 0; i < blks; i++) {
30		buf = rq->bufs[i];
31		for (j = 0; j < VNIC_RQ_BUF_BLK_ENTRIES; j++) {
32			buf->index = i * VNIC_RQ_BUF_BLK_ENTRIES + j;
33			buf->desc = (u8 *)rq->ring.descs +
34				rq->ring.desc_size * buf->index;
35			if (buf->index + 1 == count) {
36				buf->next = rq->bufs[0];
37				break;
38			} else if (j + 1 == VNIC_RQ_BUF_BLK_ENTRIES) {
39				buf->next = rq->bufs[i + 1];
40			} else {
41				buf->next = buf + 1;
42				buf++;
43			}
44		}
45	}
46
47	rq->to_use = rq->to_clean = rq->bufs[0];
48	rq->buf_index = 0;
49
50	return 0;
51}
52
53void vnic_rq_free(struct vnic_rq *rq)
54{
55	struct vnic_dev *vdev;
56	unsigned int i;
57
58	vdev = rq->vdev;
59
60	vnic_dev_free_desc_ring(vdev, &rq->ring);
61
62	for (i = 0; i < VNIC_RQ_BUF_BLKS_MAX; i++) {
63		kfree(rq->bufs[i]);
64		rq->bufs[i] = NULL;
65	}
66
67	rq->ctrl = NULL;
68}
69
70int vnic_rq_alloc(struct vnic_dev *vdev, struct vnic_rq *rq, unsigned int index,
71	unsigned int desc_count, unsigned int desc_size)
72{
73	int err;
74
75	rq->index = index;
76	rq->vdev = vdev;
77
78	rq->ctrl = vnic_dev_get_res(vdev, RES_TYPE_RQ, index);
79	if (!rq->ctrl) {
80		printk(KERN_ERR "Failed to hook RQ[%d] resource\n", index);
81		return -EINVAL;
82	}
83
84	vnic_rq_disable(rq);
85
86	err = vnic_dev_alloc_desc_ring(vdev, &rq->ring, desc_count, desc_size);
87	if (err)
88		return err;
89
90	err = vnic_rq_alloc_bufs(rq);
91	if (err) {
92		vnic_rq_free(rq);
93		return err;
94	}
95
96	return 0;
97}
98
99void vnic_rq_init(struct vnic_rq *rq, unsigned int cq_index,
100	unsigned int error_interrupt_enable,
101	unsigned int error_interrupt_offset)
102{
103	u64 paddr;
104	u32 fetch_index;
105
106	paddr = (u64)rq->ring.base_addr | VNIC_PADDR_TARGET;
107	writeq(paddr, &rq->ctrl->ring_base);
108	iowrite32(rq->ring.desc_count, &rq->ctrl->ring_size);
109	iowrite32(cq_index, &rq->ctrl->cq_index);
110	iowrite32(error_interrupt_enable, &rq->ctrl->error_interrupt_enable);
111	iowrite32(error_interrupt_offset, &rq->ctrl->error_interrupt_offset);
112	iowrite32(0, &rq->ctrl->dropped_packet_count);
113	iowrite32(0, &rq->ctrl->error_status);
114
115	/* Use current fetch_index as the ring starting point */
116	fetch_index = ioread32(&rq->ctrl->fetch_index);
117	rq->to_use = rq->to_clean =
118		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
119			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
120	iowrite32(fetch_index, &rq->ctrl->posted_index);
121
122	rq->buf_index = 0;
123}
124
125unsigned int vnic_rq_error_status(struct vnic_rq *rq)
126{
127	return ioread32(&rq->ctrl->error_status);
128}
129
130void vnic_rq_enable(struct vnic_rq *rq)
131{
132	iowrite32(1, &rq->ctrl->enable);
133}
134
135int vnic_rq_disable(struct vnic_rq *rq)
136{
137	unsigned int wait;
138
139	iowrite32(0, &rq->ctrl->enable);
140
141	/* Wait for HW to ACK disable request */
142	for (wait = 0; wait < 100; wait++) {
143		if (!(ioread32(&rq->ctrl->running)))
144			return 0;
145		udelay(1);
146	}
147
148	printk(KERN_ERR "Failed to disable RQ[%d]\n", rq->index);
149
150	return -ETIMEDOUT;
151}
152
153void vnic_rq_clean(struct vnic_rq *rq,
154	void (*buf_clean)(struct vnic_rq *rq, struct vnic_rq_buf *buf))
155{
156	struct vnic_rq_buf *buf;
157	u32 fetch_index;
158
159	WARN_ON(ioread32(&rq->ctrl->enable));
160
161	buf = rq->to_clean;
162
163	while (vnic_rq_desc_used(rq) > 0) {
164
165		(*buf_clean)(rq, buf);
166
167		buf = rq->to_clean = buf->next;
168		rq->ring.desc_avail++;
169	}
170
171	/* Use current fetch_index as the ring starting point */
172	fetch_index = ioread32(&rq->ctrl->fetch_index);
173	rq->to_use = rq->to_clean =
174		&rq->bufs[fetch_index / VNIC_RQ_BUF_BLK_ENTRIES]
175			[fetch_index % VNIC_RQ_BUF_BLK_ENTRIES];
176	iowrite32(fetch_index, &rq->ctrl->posted_index);
177
178	rq->buf_index = 0;
179
180	vnic_dev_clear_desc_ring(&rq->ring);
181}
182