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  * Setup 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 one 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: (in) number of words to read; (out) number of words actually read
217  * @data: words read from the Shadow RAM
218  *
219  * Reads 16 bit words (data buffer) from the SR using the i40e_read_nvm_srrd()
220  * method. The buffer read is preceded by the NVM ownership take
221  * and followed by the release.
222  **/
223 i40e_status i40e_read_nvm_buffer(struct i40e_hw *hw, u16 offset,
224 					   u16 *words, u16 *data)
225 {
226 	i40e_status ret_code = 0;
227 	u16 index, word;
228 
229 	/* Loop thru the selected region */
230 	for (word = 0; word < *words; word++) {
231 		index = offset + word;
232 		ret_code = i40e_read_nvm_word(hw, index, &data[word]);
233 		if (ret_code)
234 			break;
235 	}
236 
237 	/* Update the number of words read from the Shadow RAM */
238 	*words = word;
239 
240 	return ret_code;
241 }
242 
243 /**
244  * i40e_calc_nvm_checksum - Calculates and returns the checksum
245  * @hw: pointer to hardware structure
246  * @checksum: pointer to the checksum
247  *
248  * This function calculates SW Checksum that covers the whole 64kB shadow RAM
249  * except the VPD and PCIe ALT Auto-load modules. The structure and size of VPD
250  * is customer specific and unknown. Therefore, this function skips all maximum
251  * possible size of VPD (1kB).
252  **/
253 static i40e_status i40e_calc_nvm_checksum(struct i40e_hw *hw,
254 						    u16 *checksum)
255 {
256 	i40e_status ret_code = 0;
257 	u16 pcie_alt_module = 0;
258 	u16 checksum_local = 0;
259 	u16 vpd_module = 0;
260 	u16 word = 0;
261 	u32 i = 0;
262 
263 	/* read pointer to VPD area */
264 	ret_code = i40e_read_nvm_word(hw, I40E_SR_VPD_PTR, &vpd_module);
265 	if (ret_code) {
266 		ret_code = I40E_ERR_NVM_CHECKSUM;
267 		goto i40e_calc_nvm_checksum_exit;
268 	}
269 
270 	/* read pointer to PCIe Alt Auto-load module */
271 	ret_code = i40e_read_nvm_word(hw, I40E_SR_PCIE_ALT_AUTO_LOAD_PTR,
272 				       &pcie_alt_module);
273 	if (ret_code) {
274 		ret_code = I40E_ERR_NVM_CHECKSUM;
275 		goto i40e_calc_nvm_checksum_exit;
276 	}
277 
278 	/* Calculate SW checksum that covers the whole 64kB shadow RAM
279 	 * except the VPD and PCIe ALT Auto-load modules
280 	 */
281 	for (i = 0; i < hw->nvm.sr_size; i++) {
282 		/* Skip Checksum word */
283 		if (i == I40E_SR_SW_CHECKSUM_WORD)
284 			i++;
285 		/* Skip VPD module (convert byte size to word count) */
286 		if (i == (u32)vpd_module) {
287 			i += (I40E_SR_VPD_MODULE_MAX_SIZE / 2);
288 			if (i >= hw->nvm.sr_size)
289 				break;
290 		}
291 		/* Skip PCIe ALT module (convert byte size to word count) */
292 		if (i == (u32)pcie_alt_module) {
293 			i += (I40E_SR_PCIE_ALT_MODULE_MAX_SIZE / 2);
294 			if (i >= hw->nvm.sr_size)
295 				break;
296 		}
297 
298 		ret_code = i40e_read_nvm_word(hw, (u16)i, &word);
299 		if (ret_code) {
300 			ret_code = I40E_ERR_NVM_CHECKSUM;
301 			goto i40e_calc_nvm_checksum_exit;
302 		}
303 		checksum_local += word;
304 	}
305 
306 	*checksum = (u16)I40E_SR_SW_CHECKSUM_BASE - checksum_local;
307 
308 i40e_calc_nvm_checksum_exit:
309 	return ret_code;
310 }
311 
312 /**
313  * i40e_validate_nvm_checksum - Validate EEPROM checksum
314  * @hw: pointer to hardware structure
315  * @checksum: calculated checksum
316  *
317  * Performs checksum calculation and validates the NVM SW checksum. If the
318  * caller does not need checksum, the value can be NULL.
319  **/
320 i40e_status i40e_validate_nvm_checksum(struct i40e_hw *hw,
321 						 u16 *checksum)
322 {
323 	i40e_status ret_code = 0;
324 	u16 checksum_sr = 0;
325 	u16 checksum_local = 0;
326 
327 	ret_code = i40e_acquire_nvm(hw, I40E_RESOURCE_READ);
328 	if (ret_code)
329 		goto i40e_validate_nvm_checksum_exit;
330 
331 	ret_code = i40e_calc_nvm_checksum(hw, &checksum_local);
332 	if (ret_code)
333 		goto i40e_validate_nvm_checksum_free;
334 
335 	/* Do not use i40e_read_nvm_word() because we do not want to take
336 	 * the synchronization semaphores twice here.
337 	 */
338 	i40e_read_nvm_word(hw, I40E_SR_SW_CHECKSUM_WORD, &checksum_sr);
339 
340 	/* Verify read checksum from EEPROM is the same as
341 	 * calculated checksum
342 	 */
343 	if (checksum_local != checksum_sr)
344 		ret_code = I40E_ERR_NVM_CHECKSUM;
345 
346 	/* If the user cares, return the calculated checksum */
347 	if (checksum)
348 		*checksum = checksum_local;
349 
350 i40e_validate_nvm_checksum_free:
351 	i40e_release_nvm(hw);
352 
353 i40e_validate_nvm_checksum_exit:
354 	return ret_code;
355 }
356