1 /* Intel PRO/1000 Linux driver
2  * Copyright(c) 1999 - 2014 Intel Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * The full GNU General Public License is included in this distribution in
14  * the file called "COPYING".
15  *
16  * Contact Information:
17  * Linux NICS <linux.nics@intel.com>
18  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
19  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
20  */
21 
22 #include "e1000.h"
23 
24 /**
25  *  e1000_calculate_checksum - Calculate checksum for buffer
26  *  @buffer: pointer to EEPROM
27  *  @length: size of EEPROM to calculate a checksum for
28  *
29  *  Calculates the checksum for some buffer on a specified length.  The
30  *  checksum calculated is returned.
31  **/
32 static u8 e1000_calculate_checksum(u8 *buffer, u32 length)
33 {
34 	u32 i;
35 	u8 sum = 0;
36 
37 	if (!buffer)
38 		return 0;
39 
40 	for (i = 0; i < length; i++)
41 		sum += buffer[i];
42 
43 	return (u8)(0 - sum);
44 }
45 
46 /**
47  *  e1000_mng_enable_host_if - Checks host interface is enabled
48  *  @hw: pointer to the HW structure
49  *
50  *  Returns 0 upon success, else -E1000_ERR_HOST_INTERFACE_COMMAND
51  *
52  *  This function checks whether the HOST IF is enabled for command operation
53  *  and also checks whether the previous command is completed.  It busy waits
54  *  in case of previous command is not completed.
55  **/
56 static s32 e1000_mng_enable_host_if(struct e1000_hw *hw)
57 {
58 	u32 hicr;
59 	u8 i;
60 
61 	if (!hw->mac.arc_subsystem_valid) {
62 		e_dbg("ARC subsystem not valid.\n");
63 		return -E1000_ERR_HOST_INTERFACE_COMMAND;
64 	}
65 
66 	/* Check that the host interface is enabled. */
67 	hicr = er32(HICR);
68 	if (!(hicr & E1000_HICR_EN)) {
69 		e_dbg("E1000_HOST_EN bit disabled.\n");
70 		return -E1000_ERR_HOST_INTERFACE_COMMAND;
71 	}
72 	/* check the previous command is completed */
73 	for (i = 0; i < E1000_MNG_DHCP_COMMAND_TIMEOUT; i++) {
74 		hicr = er32(HICR);
75 		if (!(hicr & E1000_HICR_C))
76 			break;
77 		mdelay(1);
78 	}
79 
80 	if (i == E1000_MNG_DHCP_COMMAND_TIMEOUT) {
81 		e_dbg("Previous command timeout failed.\n");
82 		return -E1000_ERR_HOST_INTERFACE_COMMAND;
83 	}
84 
85 	return 0;
86 }
87 
88 /**
89  *  e1000e_check_mng_mode_generic - Generic check management mode
90  *  @hw: pointer to the HW structure
91  *
92  *  Reads the firmware semaphore register and returns true (>0) if
93  *  manageability is enabled, else false (0).
94  **/
95 bool e1000e_check_mng_mode_generic(struct e1000_hw *hw)
96 {
97 	u32 fwsm = er32(FWSM);
98 
99 	return (fwsm & E1000_FWSM_MODE_MASK) ==
100 	    (E1000_MNG_IAMT_MODE << E1000_FWSM_MODE_SHIFT);
101 }
102 
103 /**
104  *  e1000e_enable_tx_pkt_filtering - Enable packet filtering on Tx
105  *  @hw: pointer to the HW structure
106  *
107  *  Enables packet filtering on transmit packets if manageability is enabled
108  *  and host interface is enabled.
109  **/
110 bool e1000e_enable_tx_pkt_filtering(struct e1000_hw *hw)
111 {
112 	struct e1000_host_mng_dhcp_cookie *hdr = &hw->mng_cookie;
113 	u32 *buffer = (u32 *)&hw->mng_cookie;
114 	u32 offset;
115 	s32 ret_val, hdr_csum, csum;
116 	u8 i, len;
117 
118 	hw->mac.tx_pkt_filtering = true;
119 
120 	/* No manageability, no filtering */
121 	if (!hw->mac.ops.check_mng_mode(hw)) {
122 		hw->mac.tx_pkt_filtering = false;
123 		return hw->mac.tx_pkt_filtering;
124 	}
125 
126 	/* If we can't read from the host interface for whatever
127 	 * reason, disable filtering.
128 	 */
129 	ret_val = e1000_mng_enable_host_if(hw);
130 	if (ret_val) {
131 		hw->mac.tx_pkt_filtering = false;
132 		return hw->mac.tx_pkt_filtering;
133 	}
134 
135 	/* Read in the header.  Length and offset are in dwords. */
136 	len = E1000_MNG_DHCP_COOKIE_LENGTH >> 2;
137 	offset = E1000_MNG_DHCP_COOKIE_OFFSET >> 2;
138 	for (i = 0; i < len; i++)
139 		*(buffer + i) = E1000_READ_REG_ARRAY(hw, E1000_HOST_IF,
140 						     offset + i);
141 	hdr_csum = hdr->checksum;
142 	hdr->checksum = 0;
143 	csum = e1000_calculate_checksum((u8 *)hdr,
144 					E1000_MNG_DHCP_COOKIE_LENGTH);
145 	/* If either the checksums or signature don't match, then
146 	 * the cookie area isn't considered valid, in which case we
147 	 * take the safe route of assuming Tx filtering is enabled.
148 	 */
149 	if ((hdr_csum != csum) || (hdr->signature != E1000_IAMT_SIGNATURE)) {
150 		hw->mac.tx_pkt_filtering = true;
151 		return hw->mac.tx_pkt_filtering;
152 	}
153 
154 	/* Cookie area is valid, make the final check for filtering. */
155 	if (!(hdr->status & E1000_MNG_DHCP_COOKIE_STATUS_PARSING))
156 		hw->mac.tx_pkt_filtering = false;
157 
158 	return hw->mac.tx_pkt_filtering;
159 }
160 
161 /**
162  *  e1000_mng_write_cmd_header - Writes manageability command header
163  *  @hw: pointer to the HW structure
164  *  @hdr: pointer to the host interface command header
165  *
166  *  Writes the command header after does the checksum calculation.
167  **/
168 static s32 e1000_mng_write_cmd_header(struct e1000_hw *hw,
169 				      struct e1000_host_mng_command_header *hdr)
170 {
171 	u16 i, length = sizeof(struct e1000_host_mng_command_header);
172 
173 	/* Write the whole command header structure with new checksum. */
174 
175 	hdr->checksum = e1000_calculate_checksum((u8 *)hdr, length);
176 
177 	length >>= 2;
178 	/* Write the relevant command block into the ram area. */
179 	for (i = 0; i < length; i++) {
180 		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, i, *((u32 *)hdr + i));
181 		e1e_flush();
182 	}
183 
184 	return 0;
185 }
186 
187 /**
188  *  e1000_mng_host_if_write - Write to the manageability host interface
189  *  @hw: pointer to the HW structure
190  *  @buffer: pointer to the host interface buffer
191  *  @length: size of the buffer
192  *  @offset: location in the buffer to write to
193  *  @sum: sum of the data (not checksum)
194  *
195  *  This function writes the buffer content at the offset given on the host if.
196  *  It also does alignment considerations to do the writes in most efficient
197  *  way.  Also fills up the sum of the buffer in *buffer parameter.
198  **/
199 static s32 e1000_mng_host_if_write(struct e1000_hw *hw, u8 *buffer,
200 				   u16 length, u16 offset, u8 *sum)
201 {
202 	u8 *tmp;
203 	u8 *bufptr = buffer;
204 	u32 data = 0;
205 	u16 remaining, i, j, prev_bytes;
206 
207 	/* sum = only sum of the data and it is not checksum */
208 
209 	if (length == 0 || offset + length > E1000_HI_MAX_MNG_DATA_LENGTH)
210 		return -E1000_ERR_PARAM;
211 
212 	tmp = (u8 *)&data;
213 	prev_bytes = offset & 0x3;
214 	offset >>= 2;
215 
216 	if (prev_bytes) {
217 		data = E1000_READ_REG_ARRAY(hw, E1000_HOST_IF, offset);
218 		for (j = prev_bytes; j < sizeof(u32); j++) {
219 			*(tmp + j) = *bufptr++;
220 			*sum += *(tmp + j);
221 		}
222 		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset, data);
223 		length -= j - prev_bytes;
224 		offset++;
225 	}
226 
227 	remaining = length & 0x3;
228 	length -= remaining;
229 
230 	/* Calculate length in DWORDs */
231 	length >>= 2;
232 
233 	/* The device driver writes the relevant command block into the
234 	 * ram area.
235 	 */
236 	for (i = 0; i < length; i++) {
237 		for (j = 0; j < sizeof(u32); j++) {
238 			*(tmp + j) = *bufptr++;
239 			*sum += *(tmp + j);
240 		}
241 
242 		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset + i, data);
243 	}
244 	if (remaining) {
245 		for (j = 0; j < sizeof(u32); j++) {
246 			if (j < remaining)
247 				*(tmp + j) = *bufptr++;
248 			else
249 				*(tmp + j) = 0;
250 
251 			*sum += *(tmp + j);
252 		}
253 		E1000_WRITE_REG_ARRAY(hw, E1000_HOST_IF, offset + i, data);
254 	}
255 
256 	return 0;
257 }
258 
259 /**
260  *  e1000e_mng_write_dhcp_info - Writes DHCP info to host interface
261  *  @hw: pointer to the HW structure
262  *  @buffer: pointer to the host interface
263  *  @length: size of the buffer
264  *
265  *  Writes the DHCP information to the host interface.
266  **/
267 s32 e1000e_mng_write_dhcp_info(struct e1000_hw *hw, u8 *buffer, u16 length)
268 {
269 	struct e1000_host_mng_command_header hdr;
270 	s32 ret_val;
271 	u32 hicr;
272 
273 	hdr.command_id = E1000_MNG_DHCP_TX_PAYLOAD_CMD;
274 	hdr.command_length = length;
275 	hdr.reserved1 = 0;
276 	hdr.reserved2 = 0;
277 	hdr.checksum = 0;
278 
279 	/* Enable the host interface */
280 	ret_val = e1000_mng_enable_host_if(hw);
281 	if (ret_val)
282 		return ret_val;
283 
284 	/* Populate the host interface with the contents of "buffer". */
285 	ret_val = e1000_mng_host_if_write(hw, buffer, length,
286 					  sizeof(hdr), &(hdr.checksum));
287 	if (ret_val)
288 		return ret_val;
289 
290 	/* Write the manageability command header */
291 	ret_val = e1000_mng_write_cmd_header(hw, &hdr);
292 	if (ret_val)
293 		return ret_val;
294 
295 	/* Tell the ARC a new command is pending. */
296 	hicr = er32(HICR);
297 	ew32(HICR, hicr | E1000_HICR_C);
298 
299 	return 0;
300 }
301 
302 /**
303  *  e1000e_enable_mng_pass_thru - Check if management passthrough is needed
304  *  @hw: pointer to the HW structure
305  *
306  *  Verifies the hardware needs to leave interface enabled so that frames can
307  *  be directed to and from the management interface.
308  **/
309 bool e1000e_enable_mng_pass_thru(struct e1000_hw *hw)
310 {
311 	u32 manc;
312 	u32 fwsm, factps;
313 
314 	manc = er32(MANC);
315 
316 	if (!(manc & E1000_MANC_RCV_TCO_EN))
317 		return false;
318 
319 	if (hw->mac.has_fwsm) {
320 		fwsm = er32(FWSM);
321 		factps = er32(FACTPS);
322 
323 		if (!(factps & E1000_FACTPS_MNGCG) &&
324 		    ((fwsm & E1000_FWSM_MODE_MASK) ==
325 		     (e1000_mng_mode_pt << E1000_FWSM_MODE_SHIFT)))
326 			return true;
327 	} else if ((hw->mac.type == e1000_82574) ||
328 		   (hw->mac.type == e1000_82583)) {
329 		u16 data;
330 		s32 ret_val;
331 
332 		factps = er32(FACTPS);
333 		ret_val = e1000_read_nvm(hw, NVM_INIT_CONTROL2_REG, 1, &data);
334 		if (ret_val)
335 			return false;
336 
337 		if (!(factps & E1000_FACTPS_MNGCG) &&
338 		    ((data & E1000_NVM_INIT_CTRL2_MNGM) ==
339 		     (e1000_mng_mode_pt << 13)))
340 			return true;
341 	} else if ((manc & E1000_MANC_SMBUS_EN) &&
342 		   !(manc & E1000_MANC_ASF_EN)) {
343 		return true;
344 	}
345 
346 	return false;
347 }
348