1// SPDX-License-Identifier: GPL-2.0
2/* Copyright(c) 1999 - 2018 Intel Corporation. */
3
4#include "e1000.h"
5
6/**
7 * e1000_calculate_checksum - Calculate checksum for buffer
8 * @buffer: pointer to EEPROM
9 * @length: size of EEPROM to calculate a checksum for
10 *
11 * Calculates the checksum for some buffer on a specified length. The
12 * checksum calculated is returned.
13 **/
14static u8 e1000_calculate_checksum(u8 *buffer, u32 length)
15{
16 u32 i;
17 u8 sum = 0;
18
19 if (!buffer)
20 return 0;
21
22 for (i = 0; i < length; i++)
23 sum += buffer[i];
24
25 return (u8)(0 - sum);
26}
27
28/**
29 * e1000_mng_enable_host_if - Checks host interface is enabled
30 * @hw: pointer to the HW structure
31 *
32 * Returns 0 upon success, else -E1000_ERR_HOST_INTERFACE_COMMAND
33 *
34 * This function checks whether the HOST IF is enabled for command operation
35 * and also checks whether the previous command is completed. It busy waits
36 * in case of previous command is not completed.
37 **/
38static s32 e1000_mng_enable_host_if(struct e1000_hw *hw)
39{
40 u32 hicr;
41 u8 i;
42
43 if (!hw->mac.arc_subsystem_valid) {
44 e_dbg("ARC subsystem not valid.\n");
45 return -E1000_ERR_HOST_INTERFACE_COMMAND;
46 }
47
48 /* Check that the host interface is enabled. */
49 hicr = er32(HICR);
50 if (!(hicr & E1000_HICR_EN)) {
51 e_dbg("E1000_HOST_EN bit disabled.\n");
52 return -E1000_ERR_HOST_INTERFACE_COMMAND;
53 }
54 /* check the previous command is completed */
55 for (i = 0; i < E1000_MNG_DHCP_COMMAND_TIMEOUT; i++) {
56 hicr = er32(HICR);
57 if (!(hicr & E1000_HICR_C))
58 break;
59 mdelay(1);
60 }
61
62 if (i == E1000_MNG_DHCP_COMMAND_TIMEOUT) {
63 e_dbg("Previous command timeout failed.\n");
64 return -E1000_ERR_HOST_INTERFACE_COMMAND;
65 }
66
67 return 0;
68}
69
70/**
71 * e1000e_check_mng_mode_generic - Generic check management mode
72 * @hw: pointer to the HW structure
73 *
74 * Reads the firmware semaphore register and returns true (>0) if
75 * manageability is enabled, else false (0).
76 **/
77bool e1000e_check_mng_mode_generic(struct e1000_hw *hw)
78{
79 u32 fwsm = er32(FWSM);
80
81 return (fwsm & E1000_FWSM_MODE_MASK) ==
82 (E1000_MNG_IAMT_MODE << E1000_FWSM_MODE_SHIFT);
83}
84
85/**
86 * e1000e_enable_tx_pkt_filtering - Enable packet filtering on Tx
87 * @hw: pointer to the HW structure
88 *
89 * Enables packet filtering on transmit packets if manageability is enabled
90 * and host interface is enabled.
91 **/
92bool e1000e_enable_tx_pkt_filtering(struct e1000_hw *hw)
93{
94 struct e1000_host_mng_dhcp_cookie *hdr = &hw->mng_cookie;
95 u32 *buffer = (u32 *)&hw->mng_cookie;
96 u32 offset;
97 s32 ret_val, hdr_csum, csum;
98 u8 i, len;
99
100 hw->mac.tx_pkt_filtering = true;
101
102 /* No manageability, no filtering */
103 if (!hw->mac.ops.check_mng_mode(hw)) {
104 hw->mac.tx_pkt_filtering = false;
105 return hw->mac.tx_pkt_filtering;
106 }
107
108 /* If we can't read from the host interface for whatever
109 * reason, disable filtering.
110 */
111 ret_val = e1000_mng_enable_host_if(hw);
112 if (ret_val) {
113 hw->mac.tx_pkt_filtering = false;
114 return hw->mac.tx_pkt_filtering;
115 }
116
117 /* Read in the header. Length and offset are in dwords. */
118 len = E1000_MNG_DHCP_COOKIE_LENGTH >> 2;
119 offset = E1000_MNG_DHCP_COOKIE_OFFSET >> 2;
120 for (i = 0; i < len; i++)
121 *(buffer + i) = E1000_READ_REG_ARRAY(hw, E1000_HOST_IF,
122 offset + i);
123 hdr_csum = hdr->checksum;
124 hdr->checksum = 0;
125 csum = e1000_calculate_checksum(buffer: (u8 *)hdr,
126 E1000_MNG_DHCP_COOKIE_LENGTH);
127 /* If either the checksums or signature don't match, then
128 * the cookie area isn't considered valid, in which case we
129 * take the safe route of assuming Tx filtering is enabled.
130 */
131 if ((hdr_csum != csum) || (hdr->signature != E1000_IAMT_SIGNATURE)) {
132 hw->mac.tx_pkt_filtering = true;
133 return hw->mac.tx_pkt_filtering;
134 }
135
136 /* Cookie area is valid, make the final check for filtering. */
137 if (!(hdr->status & E1000_MNG_DHCP_COOKIE_STATUS_PARSING))
138 hw->mac.tx_pkt_filtering = false;
139
140 return hw->mac.tx_pkt_filtering;
141}
142
143/**
144 * e1000_mng_write_cmd_header - Writes manageability command header
145 * @hw: pointer to the HW structure
146 * @hdr: pointer to the host interface command header
147 *
148 * Writes the command header after does the checksum calculation.
149 **/
150static s32 e1000_mng_write_cmd_header(struct e1000_hw *hw,
151 struct e1000_host_mng_command_header *hdr)
152{
153 u16 i, length = sizeof(struct e1000_host_mng_command_header);
154
155 /* Write the whole command header structure with new checksum. */
156
157 hdr->checksum = e1000_calculate_checksum(buffer: (u8 *)hdr, length);
158
159 length >>= 2;
160 /* Write the relevant command block into the ram area. */
161 for (i = 0; i < length; i++) {
162 E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, i, *((u32 *)hdr + i));
163 e1e_flush();
164 }
165
166 return 0;
167}
168
169/**
170 * e1000_mng_host_if_write - Write to the manageability host interface
171 * @hw: pointer to the HW structure
172 * @buffer: pointer to the host interface buffer
173 * @length: size of the buffer
174 * @offset: location in the buffer to write to
175 * @sum: sum of the data (not checksum)
176 *
177 * This function writes the buffer content at the offset given on the host if.
178 * It also does alignment considerations to do the writes in most efficient
179 * way. Also fills up the sum of the buffer in *buffer parameter.
180 **/
181static s32 e1000_mng_host_if_write(struct e1000_hw *hw, u8 *buffer,
182 u16 length, u16 offset, u8 *sum)
183{
184 u8 *tmp;
185 u8 *bufptr = buffer;
186 u32 data = 0;
187 u16 remaining, i, j, prev_bytes;
188
189 /* sum = only sum of the data and it is not checksum */
190
191 if (length == 0 || offset + length > E1000_HI_MAX_MNG_DATA_LENGTH)
192 return -E1000_ERR_PARAM;
193
194 tmp = (u8 *)&data;
195 prev_bytes = offset & 0x3;
196 offset >>= 2;
197
198 if (prev_bytes) {
199 data = E1000_READ_REG_ARRAY(hw, E1000_HOST_IF, offset);
200 for (j = prev_bytes; j < sizeof(u32); j++) {
201 *(tmp + j) = *bufptr++;
202 *sum += *(tmp + j);
203 }
204 E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset, data);
205 length -= j - prev_bytes;
206 offset++;
207 }
208
209 remaining = length & 0x3;
210 length -= remaining;
211
212 /* Calculate length in DWORDs */
213 length >>= 2;
214
215 /* The device driver writes the relevant command block into the
216 * ram area.
217 */
218 for (i = 0; i < length; i++) {
219 for (j = 0; j < sizeof(u32); j++) {
220 *(tmp + j) = *bufptr++;
221 *sum += *(tmp + j);
222 }
223
224 E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset + i, data);
225 }
226 if (remaining) {
227 for (j = 0; j < sizeof(u32); j++) {
228 if (j < remaining)
229 *(tmp + j) = *bufptr++;
230 else
231 *(tmp + j) = 0;
232
233 *sum += *(tmp + j);
234 }
235 E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset + i, data);
236 }
237
238 return 0;
239}
240
241/**
242 * e1000e_mng_write_dhcp_info - Writes DHCP info to host interface
243 * @hw: pointer to the HW structure
244 * @buffer: pointer to the host interface
245 * @length: size of the buffer
246 *
247 * Writes the DHCP information to the host interface.
248 **/
249s32 e1000e_mng_write_dhcp_info(struct e1000_hw *hw, u8 *buffer, u16 length)
250{
251 struct e1000_host_mng_command_header hdr;
252 s32 ret_val;
253 u32 hicr;
254
255 hdr.command_id = E1000_MNG_DHCP_TX_PAYLOAD_CMD;
256 hdr.command_length = length;
257 hdr.reserved1 = 0;
258 hdr.reserved2 = 0;
259 hdr.checksum = 0;
260
261 /* Enable the host interface */
262 ret_val = e1000_mng_enable_host_if(hw);
263 if (ret_val)
264 return ret_val;
265
266 /* Populate the host interface with the contents of "buffer". */
267 ret_val = e1000_mng_host_if_write(hw, buffer, length,
268 offset: sizeof(hdr), sum: &(hdr.checksum));
269 if (ret_val)
270 return ret_val;
271
272 /* Write the manageability command header */
273 ret_val = e1000_mng_write_cmd_header(hw, hdr: &hdr);
274 if (ret_val)
275 return ret_val;
276
277 /* Tell the ARC a new command is pending. */
278 hicr = er32(HICR);
279 ew32(HICR, hicr | E1000_HICR_C);
280
281 return 0;
282}
283
284/**
285 * e1000e_enable_mng_pass_thru - Check if management passthrough is needed
286 * @hw: pointer to the HW structure
287 *
288 * Verifies the hardware needs to leave interface enabled so that frames can
289 * be directed to and from the management interface.
290 **/
291bool e1000e_enable_mng_pass_thru(struct e1000_hw *hw)
292{
293 u32 manc;
294 u32 fwsm, factps;
295
296 manc = er32(MANC);
297
298 if (!(manc & E1000_MANC_RCV_TCO_EN))
299 return false;
300
301 if (hw->mac.has_fwsm) {
302 fwsm = er32(FWSM);
303 factps = er32(FACTPS);
304
305 if (!(factps & E1000_FACTPS_MNGCG) &&
306 ((fwsm & E1000_FWSM_MODE_MASK) ==
307 (e1000_mng_mode_pt << E1000_FWSM_MODE_SHIFT)))
308 return true;
309 } else if ((hw->mac.type == e1000_82574) ||
310 (hw->mac.type == e1000_82583)) {
311 u16 data;
312 s32 ret_val;
313
314 factps = er32(FACTPS);
315 ret_val = e1000_read_nvm(hw, NVM_INIT_CONTROL2_REG, words: 1, data: &data);
316 if (ret_val)
317 return false;
318
319 if (!(factps & E1000_FACTPS_MNGCG) &&
320 ((data & E1000_NVM_INIT_CTRL2_MNGM) ==
321 (e1000_mng_mode_pt << 13)))
322 return true;
323 } else if ((manc & E1000_MANC_SMBUS_EN) &&
324 !(manc & E1000_MANC_ASF_EN)) {
325 return true;
326 }
327
328 return false;
329}
330

source code of linux/drivers/net/ethernet/intel/e1000e/manage.c