1 /*******************************************************************************
2  *
3  * Intel Ethernet Controller XL710 Family Linux Driver
4  * Copyright(c) 2013 - 2014 Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along
16  * with this program.  If not, see <http://www.gnu.org/licenses/>.
17  *
18  * The full GNU General Public License is included in this distribution in
19  * the file called "COPYING".
20  *
21  * Contact Information:
22  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  ******************************************************************************/
26 
27 #include "i40e_prototype.h"
28 
29 /**
30  *  i40e_init_nvm_ops - Initialize NVM function pointers.
31  *  @hw: pointer to the HW structure.
32  *
33  *  Setups the function pointers and the NVM info structure. Should be called
34  *  once per NVM initialization, e.g. inside the i40e_init_shared_code().
35  *  Please notice that the NVM term is used here (& in all methods covered
36  *  in this file) as an equivalent of the FLASH part mapped into the SR.
37  *  We are accessing FLASH always thru the Shadow RAM.
38  **/
39 i40e_status i40e_init_nvm(struct i40e_hw *hw)
40 {
41 	struct i40e_nvm_info *nvm = &hw->nvm;
42 	i40e_status ret_code = 0;
43 	u32 fla, gens;
44 	u8 sr_size;
45 
46 	/* The SR size is stored regardless of the nvm programming mode
47 	 * as the blank mode may be used in the factory line.
48 	 */
49 	gens = rd32(hw, I40E_GLNVM_GENS);
50 	sr_size = ((gens & I40E_GLNVM_GENS_SR_SIZE_MASK) >>
51 			   I40E_GLNVM_GENS_SR_SIZE_SHIFT);
52 	/* Switching to words (sr_size contains power of 2KB). */
53 	nvm->sr_size = (1 << sr_size) * I40E_SR_WORDS_IN_1KB;
54 
55 	/* Check if we are in the normal or blank NVM programming mode. */
56 	fla = rd32(hw, I40E_GLNVM_FLA);
57 	if (fla & I40E_GLNVM_FLA_LOCKED_MASK) { /* Normal programming mode. */
58 		/* Max NVM timeout. */
59 		nvm->timeout = I40E_MAX_NVM_TIMEOUT;
60 		nvm->blank_nvm_mode = false;
61 	} else { /* Blank programming mode. */
62 		nvm->blank_nvm_mode = true;
63 		ret_code = I40E_ERR_NVM_BLANK_MODE;
64 		hw_dbg(hw, "NVM init error: unsupported blank mode.\n");
65 	}
66 
67 	return ret_code;
68 }
69 
70 /**
71  *  i40e_acquire_nvm - Generic request for acquiring the NVM ownership.
72  *  @hw: pointer to the HW structure.
73  *  @access: NVM access type (read or write).
74  *
75  *  This function will request NVM ownership for reading
76  *  via the proper Admin Command.
77  **/
78 i40e_status i40e_acquire_nvm(struct i40e_hw *hw,
79 				       enum i40e_aq_resource_access_type access)
80 {
81 	i40e_status ret_code = 0;
82 	u64 gtime, timeout;
83 	u64 time = 0;
84 
85 	if (hw->nvm.blank_nvm_mode)
86 		goto i40e_i40e_acquire_nvm_exit;
87 
88 	ret_code = i40e_aq_request_resource(hw, I40E_NVM_RESOURCE_ID, access,
89 					    0, &time, NULL);
90 	/* Reading the Global Device Timer. */
91 	gtime = rd32(hw, I40E_GLVFGEN_TIMER);
92 
93 	/* Store the timeout. */
94 	hw->nvm.hw_semaphore_timeout = I40E_MS_TO_GTIME(time) + gtime;
95 
96 	if (ret_code) {
97 		/* Set the polling timeout. */
98 		if (time > I40E_MAX_NVM_TIMEOUT)
99 			timeout = I40E_MS_TO_GTIME(I40E_MAX_NVM_TIMEOUT)
100 				  + gtime;
101 		else
102 			timeout = hw->nvm.hw_semaphore_timeout;
103 		/* Poll until the current NVM owner timeouts. */
104 		while (gtime < timeout) {
105 			usleep_range(10000, 20000);
106 			ret_code = i40e_aq_request_resource(hw,
107 							I40E_NVM_RESOURCE_ID,
108 							access, 0, &time,
109 							NULL);
110 			if (!ret_code) {
111 				hw->nvm.hw_semaphore_timeout =
112 						I40E_MS_TO_GTIME(time) + gtime;
113 				break;
114 			}
115 			gtime = rd32(hw, I40E_GLVFGEN_TIMER);
116 		}
117 		if (ret_code) {
118 			hw->nvm.hw_semaphore_timeout = 0;
119 			hw->nvm.hw_semaphore_wait =
120 						I40E_MS_TO_GTIME(time) + gtime;
121 			hw_dbg(hw, "NVM acquire timed out, wait %llu ms before trying again.\n",
122 				  time);
123 		}
124 	}
125 
126 i40e_i40e_acquire_nvm_exit:
127 	return ret_code;
128 }
129 
130 /**
131  *  i40e_release_nvm - Generic request for releasing the NVM ownership.
132  *  @hw: pointer to the HW structure.
133  *
134  *  This function will release NVM resource via the proper Admin Command.
135  **/
136 void i40e_release_nvm(struct i40e_hw *hw)
137 {
138 	if (!hw->nvm.blank_nvm_mode)
139 		i40e_aq_release_resource(hw, I40E_NVM_RESOURCE_ID, 0, NULL);
140 }
141 
142 /**
143  *  i40e_poll_sr_srctl_done_bit - Polls the GLNVM_SRCTL done bit.
144  *  @hw: pointer to the HW structure.
145  *
146  *  Polls the SRCTL Shadow RAM register done bit.
147  **/
148 static i40e_status i40e_poll_sr_srctl_done_bit(struct i40e_hw *hw)
149 {
150 	i40e_status ret_code = I40E_ERR_TIMEOUT;
151 	u32 srctl, wait_cnt;
152 
153 	/* Poll the I40E_GLNVM_SRCTL until the done bit is set. */
154 	for (wait_cnt = 0; wait_cnt < I40E_SRRD_SRCTL_ATTEMPTS; wait_cnt++) {
155 		srctl = rd32(hw, I40E_GLNVM_SRCTL);
156 		if (srctl & I40E_GLNVM_SRCTL_DONE_MASK) {
157 			ret_code = 0;
158 			break;
159 		}
160 		udelay(5);
161 	}
162 	if (ret_code == I40E_ERR_TIMEOUT)
163 		hw_dbg(hw, "Done bit in GLNVM_SRCTL not set");
164 	return ret_code;
165 }
166 
167 /**
168  *  i40e_read_nvm_word - Reads Shadow RAM
169  *  @hw: pointer to the HW structure.
170  *  @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
171  *  @data: word read from the Shadow RAM.
172  *
173  *  Reads 16 bit word from the Shadow RAM using the GLNVM_SRCTL register.
174  **/
175 i40e_status i40e_read_nvm_word(struct i40e_hw *hw, u16 offset,
176 					 u16 *data)
177 {
178 	i40e_status ret_code = I40E_ERR_TIMEOUT;
179 	u32 sr_reg;
180 
181 	if (offset >= hw->nvm.sr_size) {
182 		hw_dbg(hw, "NVM read error: Offset beyond Shadow RAM limit.\n");
183 		ret_code = I40E_ERR_PARAM;
184 		goto read_nvm_exit;
185 	}
186 
187 	/* Poll the done bit first. */
188 	ret_code = i40e_poll_sr_srctl_done_bit(hw);
189 	if (!ret_code) {
190 		/* Write the address and start reading. */
191 		sr_reg = (u32)(offset << I40E_GLNVM_SRCTL_ADDR_SHIFT) |
192 			 (1 << I40E_GLNVM_SRCTL_START_SHIFT);
193 		wr32(hw, I40E_GLNVM_SRCTL, sr_reg);
194 
195 		/* Poll I40E_GLNVM_SRCTL until the done bit is set. */
196 		ret_code = i40e_poll_sr_srctl_done_bit(hw);
197 		if (!ret_code) {
198 			sr_reg = rd32(hw, I40E_GLNVM_SRDATA);
199 			*data = (u16)((sr_reg &
200 				       I40E_GLNVM_SRDATA_RDDATA_MASK)
201 				    >> I40E_GLNVM_SRDATA_RDDATA_SHIFT);
202 		}
203 	}
204 	if (ret_code)
205 		hw_dbg(hw, "NVM read error: Couldn't access Shadow RAM address: 0x%x\n",
206 			  offset);
207 
208 read_nvm_exit:
209 	return ret_code;
210 }
211 
212 /**
213  *  i40e_read_nvm_buffer - Reads Shadow RAM buffer.
214  *  @hw: pointer to the HW structure.
215  *  @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
216  *  @words: number of words to read (in) &
217  *          number of words read before the NVM ownership timeout (out).
218  *  @data: words read from the Shadow RAM.
219  *
220  *  Reads 16 bit words (data buffer) from the SR using the i40e_read_nvm_srrd()
221  *  method. The buffer read is preceded by the NVM ownership take
222  *  and followed by the release.
223  **/
224 i40e_status i40e_read_nvm_buffer(struct i40e_hw *hw, u16 offset,
225 					   u16 *words, u16 *data)
226 {
227 	i40e_status ret_code = 0;
228 	u16 index, word;
229 
230 	/* Loop thru the selected region. */
231 	for (word = 0; word < *words; word++) {
232 		index = offset + word;
233 		ret_code = i40e_read_nvm_word(hw, index, &data[word]);
234 		if (ret_code)
235 			break;
236 	}
237 
238 	/* Update the number of words read from the Shadow RAM. */
239 	*words = word;
240 
241 	return ret_code;
242 }
243 
244 /**
245  *  i40e_calc_nvm_checksum - Calculates and returns the checksum
246  *  @hw: pointer to hardware structure
247  *  @checksum: pointer to the checksum
248  *
249  *  This function calculate SW Checksum that covers the whole 64kB shadow RAM
250  *  except the VPD and PCIe ALT Auto-load modules. The structure and size of VPD
251  *  is customer specific and unknown. Therefore, this function skips all maximum
252  *  possible size of VPD (1kB).
253  **/
254 static i40e_status i40e_calc_nvm_checksum(struct i40e_hw *hw,
255 						    u16 *checksum)
256 {
257 	i40e_status ret_code = 0;
258 	u16 pcie_alt_module = 0;
259 	u16 checksum_local = 0;
260 	u16 vpd_module = 0;
261 	u16 word = 0;
262 	u32 i = 0;
263 
264 	/* read pointer to VPD area */
265 	ret_code = i40e_read_nvm_word(hw, I40E_SR_VPD_PTR, &vpd_module);
266 	if (ret_code) {
267 		ret_code = I40E_ERR_NVM_CHECKSUM;
268 		goto i40e_calc_nvm_checksum_exit;
269 	}
270 
271 	/* read pointer to PCIe Alt Auto-load module */
272 	ret_code = i40e_read_nvm_word(hw, I40E_SR_PCIE_ALT_AUTO_LOAD_PTR,
273 				       &pcie_alt_module);
274 	if (ret_code) {
275 		ret_code = I40E_ERR_NVM_CHECKSUM;
276 		goto i40e_calc_nvm_checksum_exit;
277 	}
278 
279 	/* Calculate SW checksum that covers the whole 64kB shadow RAM
280 	 * except the VPD and PCIe ALT Auto-load modules
281 	 */
282 	for (i = 0; i < hw->nvm.sr_size; i++) {
283 		/* Skip Checksum word */
284 		if (i == I40E_SR_SW_CHECKSUM_WORD)
285 			i++;
286 		/* Skip VPD module (convert byte size to word count) */
287 		if (i == (u32)vpd_module) {
288 			i += (I40E_SR_VPD_MODULE_MAX_SIZE / 2);
289 			if (i >= hw->nvm.sr_size)
290 				break;
291 		}
292 		/* Skip PCIe ALT module (convert byte size to word count) */
293 		if (i == (u32)pcie_alt_module) {
294 			i += (I40E_SR_PCIE_ALT_MODULE_MAX_SIZE / 2);
295 			if (i >= hw->nvm.sr_size)
296 				break;
297 		}
298 
299 		ret_code = i40e_read_nvm_word(hw, (u16)i, &word);
300 		if (ret_code) {
301 			ret_code = I40E_ERR_NVM_CHECKSUM;
302 			goto i40e_calc_nvm_checksum_exit;
303 		}
304 		checksum_local += word;
305 	}
306 
307 	*checksum = (u16)I40E_SR_SW_CHECKSUM_BASE - checksum_local;
308 
309 i40e_calc_nvm_checksum_exit:
310 	return ret_code;
311 }
312 
313 /**
314  *  i40e_validate_nvm_checksum - Validate EEPROM checksum
315  *  @hw: pointer to hardware structure
316  *  @checksum: calculated checksum
317  *
318  *  Performs checksum calculation and validates the NVM SW checksum. If the
319  *  caller does not need checksum, the value can be NULL.
320  **/
321 i40e_status i40e_validate_nvm_checksum(struct i40e_hw *hw,
322 						 u16 *checksum)
323 {
324 	i40e_status ret_code = 0;
325 	u16 checksum_sr = 0;
326 	u16 checksum_local = 0;
327 
328 	ret_code = i40e_acquire_nvm(hw, I40E_RESOURCE_READ);
329 	if (ret_code)
330 		goto i40e_validate_nvm_checksum_exit;
331 
332 	ret_code = i40e_calc_nvm_checksum(hw, &checksum_local);
333 	if (ret_code)
334 		goto i40e_validate_nvm_checksum_free;
335 
336 	/* Do not use i40e_read_nvm_word() because we do not want to take
337 	 * the synchronization semaphores twice here.
338 	 */
339 	i40e_read_nvm_word(hw, I40E_SR_SW_CHECKSUM_WORD, &checksum_sr);
340 
341 	/* Verify read checksum from EEPROM is the same as
342 	 * calculated checksum
343 	 */
344 	if (checksum_local != checksum_sr)
345 		ret_code = I40E_ERR_NVM_CHECKSUM;
346 
347 	/* If the user cares, return the calculated checksum */
348 	if (checksum)
349 		*checksum = checksum_local;
350 
351 i40e_validate_nvm_checksum_free:
352 	i40e_release_nvm(hw);
353 
354 i40e_validate_nvm_checksum_exit:
355 	return ret_code;
356 }
357