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 **/
32static 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 **/
56static 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 **/
95bool 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 **/
110bool 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 **/
168static 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 **/
199static 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 **/
267s32 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 **/
309bool 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