GNU Linux-libre 4.19.286-gnu1
[releases.git] / drivers / net / ethernet / netronome / nfp / nfp_net_ctrl.c
1 /*
2  * Copyright (C) 2018 Netronome Systems, Inc.
3  *
4  * This software is dual licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree or the BSD 2-Clause License provided below.  You have the
7  * option to license this software under the complete terms of either license.
8  *
9  * The BSD 2-Clause License:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      1. Redistributions of source code must retain the above
16  *         copyright notice, this list of conditions and the following
17  *         disclaimer.
18  *
19  *      2. Redistributions in binary form must reproduce the above
20  *         copyright notice, this list of conditions and the following
21  *         disclaimer in the documentation and/or other materials
22  *         provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33
34 #include <linux/bitfield.h>
35 #include <linux/device.h>
36 #include <linux/kernel.h>
37 #include <linux/types.h>
38
39 #include "nfp_net_ctrl.h"
40 #include "nfp_net.h"
41
42 static void nfp_net_tlv_caps_reset(struct nfp_net_tlv_caps *caps)
43 {
44         memset(caps, 0, sizeof(*caps));
45         caps->me_freq_mhz = 1200;
46         caps->mbox_off = NFP_NET_CFG_MBOX_BASE;
47         caps->mbox_len = NFP_NET_CFG_MBOX_VAL_MAX_SZ;
48 }
49
50 int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
51                            struct nfp_net_tlv_caps *caps)
52 {
53         u8 __iomem *data = ctrl_mem + NFP_NET_CFG_TLV_BASE;
54         u8 __iomem *end = ctrl_mem + NFP_NET_CFG_BAR_SZ;
55         u32 hdr;
56
57         nfp_net_tlv_caps_reset(caps);
58
59         hdr = readl(data);
60         if (!hdr)
61                 return 0;
62
63         while (true) {
64                 unsigned int length, offset;
65                 u32 hdr = readl(data);
66
67                 length = FIELD_GET(NFP_NET_CFG_TLV_HEADER_LENGTH, hdr);
68                 offset = data - ctrl_mem;
69
70                 /* Advance past the header */
71                 data += 4;
72
73                 if (length % NFP_NET_CFG_TLV_LENGTH_INC) {
74                         dev_err(dev, "TLV size not multiple of %u len:%u\n",
75                                 NFP_NET_CFG_TLV_LENGTH_INC, length);
76                         return -EINVAL;
77                 }
78                 if (data + length > end) {
79                         dev_err(dev, "oversized TLV offset:%u len:%u\n",
80                                 offset, length);
81                         return -EINVAL;
82                 }
83
84                 switch (FIELD_GET(NFP_NET_CFG_TLV_HEADER_TYPE, hdr)) {
85                 case NFP_NET_CFG_TLV_TYPE_UNKNOWN:
86                         dev_err(dev, "NULL TLV at offset:%u\n", offset);
87                         return -EINVAL;
88                 case NFP_NET_CFG_TLV_TYPE_RESERVED:
89                         break;
90                 case NFP_NET_CFG_TLV_TYPE_END:
91                         if (!length)
92                                 return 0;
93
94                         dev_err(dev, "END TLV should be empty, has len:%d\n",
95                                 length);
96                         return -EINVAL;
97                 case NFP_NET_CFG_TLV_TYPE_ME_FREQ:
98                         if (length != 4) {
99                                 dev_err(dev,
100                                         "ME FREQ TLV should be 4B, is %dB\n",
101                                         length);
102                                 return -EINVAL;
103                         }
104
105                         caps->me_freq_mhz = readl(data);
106                         break;
107                 case NFP_NET_CFG_TLV_TYPE_MBOX:
108                         if (!length) {
109                                 caps->mbox_off = 0;
110                                 caps->mbox_len = 0;
111                         } else {
112                                 caps->mbox_off = data - ctrl_mem;
113                                 caps->mbox_len = length;
114                         }
115                         break;
116                 default:
117                         if (!FIELD_GET(NFP_NET_CFG_TLV_HEADER_REQUIRED, hdr))
118                                 break;
119
120                         dev_err(dev, "unknown TLV type:%u offset:%u len:%u\n",
121                                 FIELD_GET(NFP_NET_CFG_TLV_HEADER_TYPE, hdr),
122                                 offset, length);
123                         return -EINVAL;
124                 }
125
126                 data += length;
127                 if (data + 4 > end) {
128                         dev_err(dev, "reached end of BAR without END TLV\n");
129                         return -EINVAL;
130                 }
131         }
132
133         /* Not reached */
134         return -EINVAL;
135 }