xref: /openbmc/linux/net/ethtool/eeprom.c (revision 877013bc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <linux/ethtool.h>
4 #include <linux/sfp.h>
5 #include "netlink.h"
6 #include "common.h"
7 
8 struct eeprom_req_info {
9 	struct ethnl_req_info	base;
10 	u32			offset;
11 	u32			length;
12 	u8			page;
13 	u8			bank;
14 	u8			i2c_address;
15 };
16 
17 struct eeprom_reply_data {
18 	struct ethnl_reply_data base;
19 	u32			length;
20 	u8			*data;
21 };
22 
23 #define MODULE_EEPROM_REQINFO(__req_base) \
24 	container_of(__req_base, struct eeprom_req_info, base)
25 
26 #define MODULE_EEPROM_REPDATA(__reply_base) \
27 	container_of(__reply_base, struct eeprom_reply_data, base)
28 
29 static int fallback_set_params(struct eeprom_req_info *request,
30 			       struct ethtool_modinfo *modinfo,
31 			       struct ethtool_eeprom *eeprom)
32 {
33 	u32 offset = request->offset;
34 	u32 length = request->length;
35 
36 	if (request->page)
37 		offset = request->page * ETH_MODULE_EEPROM_PAGE_LEN + offset;
38 
39 	if (modinfo->type == ETH_MODULE_SFF_8079 &&
40 	    request->i2c_address == 0x51)
41 		offset += ETH_MODULE_EEPROM_PAGE_LEN * 2;
42 
43 	if (offset >= modinfo->eeprom_len)
44 		return -EINVAL;
45 
46 	eeprom->cmd = ETHTOOL_GMODULEEEPROM;
47 	eeprom->len = length;
48 	eeprom->offset = offset;
49 
50 	return 0;
51 }
52 
53 static int eeprom_fallback(struct eeprom_req_info *request,
54 			   struct eeprom_reply_data *reply,
55 			   struct genl_info *info)
56 {
57 	struct net_device *dev = reply->base.dev;
58 	struct ethtool_modinfo modinfo = {0};
59 	struct ethtool_eeprom eeprom = {0};
60 	u8 *data;
61 	int err;
62 
63 	modinfo.cmd = ETHTOOL_GMODULEINFO;
64 	err = ethtool_get_module_info_call(dev, &modinfo);
65 	if (err < 0)
66 		return err;
67 
68 	err = fallback_set_params(request, &modinfo, &eeprom);
69 	if (err < 0)
70 		return err;
71 
72 	data = kmalloc(eeprom.len, GFP_KERNEL);
73 	if (!data)
74 		return -ENOMEM;
75 	err = ethtool_get_module_eeprom_call(dev, &eeprom, data);
76 	if (err < 0)
77 		goto err_out;
78 
79 	reply->data = data;
80 	reply->length = eeprom.len;
81 
82 	return 0;
83 
84 err_out:
85 	kfree(data);
86 	return err;
87 }
88 
89 static int get_module_eeprom_by_page(struct net_device *dev,
90 				     struct ethtool_module_eeprom *page_data,
91 				     struct netlink_ext_ack *extack)
92 {
93 	const struct ethtool_ops *ops = dev->ethtool_ops;
94 
95 	if (dev->sfp_bus)
96 		return sfp_get_module_eeprom_by_page(dev->sfp_bus, page_data, extack);
97 
98 	if (ops->get_module_info)
99 		return ops->get_module_eeprom_by_page(dev, page_data, extack);
100 
101 	return -EOPNOTSUPP;
102 }
103 
104 static int eeprom_prepare_data(const struct ethnl_req_info *req_base,
105 			       struct ethnl_reply_data *reply_base,
106 			       struct genl_info *info)
107 {
108 	struct eeprom_reply_data *reply = MODULE_EEPROM_REPDATA(reply_base);
109 	struct eeprom_req_info *request = MODULE_EEPROM_REQINFO(req_base);
110 	struct ethtool_module_eeprom page_data = {0};
111 	struct net_device *dev = reply_base->dev;
112 	int ret;
113 
114 	page_data.offset = request->offset;
115 	page_data.length = request->length;
116 	page_data.i2c_address = request->i2c_address;
117 	page_data.page = request->page;
118 	page_data.bank = request->bank;
119 	page_data.data = kmalloc(page_data.length, GFP_KERNEL);
120 	if (!page_data.data)
121 		return -ENOMEM;
122 
123 	ret = ethnl_ops_begin(dev);
124 	if (ret)
125 		goto err_free;
126 
127 	ret = get_module_eeprom_by_page(dev, &page_data, info->extack);
128 	if (ret < 0)
129 		goto err_ops;
130 
131 	reply->length = ret;
132 	reply->data = page_data.data;
133 
134 	ethnl_ops_complete(dev);
135 	return 0;
136 
137 err_ops:
138 	ethnl_ops_complete(dev);
139 err_free:
140 	kfree(page_data.data);
141 
142 	if (ret == -EOPNOTSUPP)
143 		return eeprom_fallback(request, reply, info);
144 	return ret;
145 }
146 
147 static int eeprom_parse_request(struct ethnl_req_info *req_info, struct nlattr **tb,
148 				struct netlink_ext_ack *extack)
149 {
150 	struct eeprom_req_info *request = MODULE_EEPROM_REQINFO(req_info);
151 
152 	if (!tb[ETHTOOL_A_MODULE_EEPROM_OFFSET] ||
153 	    !tb[ETHTOOL_A_MODULE_EEPROM_LENGTH] ||
154 	    !tb[ETHTOOL_A_MODULE_EEPROM_PAGE] ||
155 	    !tb[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS])
156 		return -EINVAL;
157 
158 	request->i2c_address = nla_get_u8(tb[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS]);
159 	request->offset = nla_get_u32(tb[ETHTOOL_A_MODULE_EEPROM_OFFSET]);
160 	request->length = nla_get_u32(tb[ETHTOOL_A_MODULE_EEPROM_LENGTH]);
161 
162 	if (!request->length)
163 		return -EINVAL;
164 
165 	/* The following set of conditions limit the API to only dump 1/2
166 	 * EEPROM page without crossing low page boundary located at offset 128.
167 	 * This means user may only request dumps of length limited to 128 from
168 	 * either low 128 bytes or high 128 bytes.
169 	 * For pages higher than 0 only high 128 bytes are accessible.
170 	 */
171 	request->page = nla_get_u8(tb[ETHTOOL_A_MODULE_EEPROM_PAGE]);
172 	if (request->page && request->offset < ETH_MODULE_EEPROM_PAGE_LEN) {
173 		NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_MODULE_EEPROM_PAGE],
174 				    "reading from lower half page is allowed for page 0 only");
175 		return -EINVAL;
176 	}
177 
178 	if (request->offset < ETH_MODULE_EEPROM_PAGE_LEN &&
179 	    request->offset + request->length > ETH_MODULE_EEPROM_PAGE_LEN) {
180 		NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_MODULE_EEPROM_LENGTH],
181 				    "reading cross half page boundary is illegal");
182 		return -EINVAL;
183 	} else if (request->offset >= ETH_MODULE_EEPROM_PAGE_LEN * 2) {
184 		NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_MODULE_EEPROM_OFFSET],
185 				    "offset is out of bounds");
186 		return -EINVAL;
187 	} else if (request->offset + request->length > ETH_MODULE_EEPROM_PAGE_LEN * 2) {
188 		NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_MODULE_EEPROM_LENGTH],
189 				    "reading cross page boundary is illegal");
190 		return -EINVAL;
191 	}
192 
193 	if (tb[ETHTOOL_A_MODULE_EEPROM_BANK])
194 		request->bank = nla_get_u8(tb[ETHTOOL_A_MODULE_EEPROM_BANK]);
195 
196 	return 0;
197 }
198 
199 static int eeprom_reply_size(const struct ethnl_req_info *req_base,
200 			     const struct ethnl_reply_data *reply_base)
201 {
202 	const struct eeprom_req_info *request = MODULE_EEPROM_REQINFO(req_base);
203 
204 	return nla_total_size(sizeof(u8) * request->length); /* _EEPROM_DATA */
205 }
206 
207 static int eeprom_fill_reply(struct sk_buff *skb,
208 			     const struct ethnl_req_info *req_base,
209 			     const struct ethnl_reply_data *reply_base)
210 {
211 	struct eeprom_reply_data *reply = MODULE_EEPROM_REPDATA(reply_base);
212 
213 	return nla_put(skb, ETHTOOL_A_MODULE_EEPROM_DATA, reply->length, reply->data);
214 }
215 
216 static void eeprom_cleanup_data(struct ethnl_reply_data *reply_base)
217 {
218 	struct eeprom_reply_data *reply = MODULE_EEPROM_REPDATA(reply_base);
219 
220 	kfree(reply->data);
221 }
222 
223 const struct ethnl_request_ops ethnl_module_eeprom_request_ops = {
224 	.request_cmd		= ETHTOOL_MSG_MODULE_EEPROM_GET,
225 	.reply_cmd		= ETHTOOL_MSG_MODULE_EEPROM_GET_REPLY,
226 	.hdr_attr		= ETHTOOL_A_MODULE_EEPROM_HEADER,
227 	.req_info_size		= sizeof(struct eeprom_req_info),
228 	.reply_data_size	= sizeof(struct eeprom_reply_data),
229 
230 	.parse_request		= eeprom_parse_request,
231 	.prepare_data		= eeprom_prepare_data,
232 	.reply_size		= eeprom_reply_size,
233 	.fill_reply		= eeprom_fill_reply,
234 	.cleanup_data		= eeprom_cleanup_data,
235 };
236 
237 const struct nla_policy ethnl_module_eeprom_get_policy[] = {
238 	[ETHTOOL_A_MODULE_EEPROM_HEADER]	= NLA_POLICY_NESTED(ethnl_header_policy),
239 	[ETHTOOL_A_MODULE_EEPROM_OFFSET]	= { .type = NLA_U32 },
240 	[ETHTOOL_A_MODULE_EEPROM_LENGTH]	= { .type = NLA_U32 },
241 	[ETHTOOL_A_MODULE_EEPROM_PAGE]		= { .type = NLA_U8 },
242 	[ETHTOOL_A_MODULE_EEPROM_BANK]		= { .type = NLA_U8 },
243 	[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS]	=
244 		NLA_POLICY_RANGE(NLA_U8, 0, ETH_MODULE_MAX_I2C_ADDRESS),
245 };
246 
247