1 /*******************************************************************************
2  *
3  * Intel Ethernet Controller XL710 Family Linux Driver
4  * Copyright(c) 2013 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 with
16  * this program; if not, write to the Free Software Foundation, Inc.,
17  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * The full GNU General Public License is included in this distribution in
20  * the file called "COPYING".
21  *
22  * Contact Information:
23  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
24  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
25  *
26  ******************************************************************************/
27 
28 #include "i40e_prototype.h"
29 
30 /**
31  *  i40e_init_nvm_ops - Initialize NVM function pointers.
32  *  @hw: pointer to the HW structure.
33  *
34  *  Setups the function pointers and the NVM info structure. Should be called
35  *  once per NVM initialization, e.g. inside the i40e_init_shared_code().
36  *  Please notice that the NVM term is used here (& in all methods covered
37  *  in this file) as an equivalent of the FLASH part mapped into the SR.
38  *  We are accessing FLASH always thru the Shadow RAM.
39  **/
40 i40e_status i40e_init_nvm(struct i40e_hw *hw)
41 {
42 	struct i40e_nvm_info *nvm = &hw->nvm;
43 	i40e_status ret_code = 0;
44 	u32 fla, gens;
45 	u8 sr_size;
46 
47 	/* The SR size is stored regardless of the nvm programming mode
48 	 * as the blank mode may be used in the factory line.
49 	 */
50 	gens = rd32(hw, I40E_GLNVM_GENS);
51 	sr_size = ((gens & I40E_GLNVM_GENS_SR_SIZE_MASK) >>
52 			   I40E_GLNVM_GENS_SR_SIZE_SHIFT);
53 	/* Switching to words (sr_size contains power of 2KB). */
54 	nvm->sr_size = (1 << sr_size) * I40E_SR_WORDS_IN_1KB;
55 
56 	/* Check if we are in the normal or blank NVM programming mode. */
57 	fla = rd32(hw, I40E_GLNVM_FLA);
58 	if (fla & I40E_GLNVM_FLA_LOCKED_MASK) { /* Normal programming mode. */
59 		/* Max NVM timeout. */
60 		nvm->timeout = I40E_MAX_NVM_TIMEOUT;
61 		nvm->blank_nvm_mode = false;
62 	} else { /* Blank programming mode. */
63 		nvm->blank_nvm_mode = true;
64 		ret_code = I40E_ERR_NVM_BLANK_MODE;
65 		hw_dbg(hw, "NVM init error: unsupported blank mode.\n");
66 	}
67 
68 	return ret_code;
69 }
70 
71 /**
72  *  i40e_acquire_nvm - Generic request for acquiring the NVM ownership.
73  *  @hw: pointer to the HW structure.
74  *  @access: NVM access type (read or write).
75  *
76  *  This function will request NVM ownership for reading
77  *  via the proper Admin Command.
78  **/
79 i40e_status i40e_acquire_nvm(struct i40e_hw *hw,
80 				       enum i40e_aq_resource_access_type access)
81 {
82 	i40e_status ret_code = 0;
83 	u64 gtime, timeout;
84 	u64 time = 0;
85 
86 	if (hw->nvm.blank_nvm_mode)
87 		goto i40e_i40e_acquire_nvm_exit;
88 
89 	ret_code = i40e_aq_request_resource(hw, I40E_NVM_RESOURCE_ID, access,
90 					    0, &time, NULL);
91 	/* Reading the Global Device Timer. */
92 	gtime = rd32(hw, I40E_GLVFGEN_TIMER);
93 
94 	/* Store the timeout. */
95 	hw->nvm.hw_semaphore_timeout = I40E_MS_TO_GTIME(time) + gtime;
96 
97 	if (ret_code) {
98 		/* Set the polling timeout. */
99 		if (time > I40E_MAX_NVM_TIMEOUT)
100 			timeout = I40E_MS_TO_GTIME(I40E_MAX_NVM_TIMEOUT)
101 				  + gtime;
102 		else
103 			timeout = hw->nvm.hw_semaphore_timeout;
104 		/* Poll until the current NVM owner timeouts. */
105 		while (gtime < timeout) {
106 			usleep_range(10000, 20000);
107 			ret_code = i40e_aq_request_resource(hw,
108 							I40E_NVM_RESOURCE_ID,
109 							access, 0, &time,
110 							NULL);
111 			if (!ret_code) {
112 				hw->nvm.hw_semaphore_timeout =
113 						I40E_MS_TO_GTIME(time) + gtime;
114 				break;
115 			}
116 			gtime = rd32(hw, I40E_GLVFGEN_TIMER);
117 		}
118 		if (ret_code) {
119 			hw->nvm.hw_semaphore_timeout = 0;
120 			hw->nvm.hw_semaphore_wait =
121 						I40E_MS_TO_GTIME(time) + gtime;
122 			hw_dbg(hw, "NVM acquire timed out, wait %llu ms before trying again.\n",
123 				  time);
124 		}
125 	}
126 
127 i40e_i40e_acquire_nvm_exit:
128 	return ret_code;
129 }
130 
131 /**
132  *  i40e_release_nvm - Generic request for releasing the NVM ownership.
133  *  @hw: pointer to the HW structure.
134  *
135  *  This function will release NVM resource via the proper Admin Command.
136  **/
137 void i40e_release_nvm(struct i40e_hw *hw)
138 {
139 	if (!hw->nvm.blank_nvm_mode)
140 		i40e_aq_release_resource(hw, I40E_NVM_RESOURCE_ID, 0, NULL);
141 }
142 
143 /**
144  *  i40e_poll_sr_srctl_done_bit - Polls the GLNVM_SRCTL done bit.
145  *  @hw: pointer to the HW structure.
146  *
147  *  Polls the SRCTL Shadow RAM register done bit.
148  **/
149 static i40e_status i40e_poll_sr_srctl_done_bit(struct i40e_hw *hw)
150 {
151 	i40e_status ret_code = I40E_ERR_TIMEOUT;
152 	u32 srctl, wait_cnt;
153 
154 	/* Poll the I40E_GLNVM_SRCTL until the done bit is set. */
155 	for (wait_cnt = 0; wait_cnt < I40E_SRRD_SRCTL_ATTEMPTS; wait_cnt++) {
156 		srctl = rd32(hw, I40E_GLNVM_SRCTL);
157 		if (srctl & I40E_GLNVM_SRCTL_DONE_MASK) {
158 			ret_code = 0;
159 			break;
160 		}
161 		udelay(5);
162 	}
163 	if (ret_code == I40E_ERR_TIMEOUT)
164 		hw_dbg(hw, "Done bit in GLNVM_SRCTL not set");
165 	return ret_code;
166 }
167 
168 /**
169  *  i40e_read_nvm_srctl - Reads Shadow RAM.
170  *  @hw: pointer to the HW structure.
171  *  @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
172  *  @data: word read from the Shadow RAM.
173  *
174  *  Reads 16 bit word from the Shadow RAM using the GLNVM_SRCTL register.
175  **/
176 static i40e_status i40e_read_nvm_srctl(struct i40e_hw *hw, u16 offset,
177 						 u16 *data)
178 {
179 	i40e_status ret_code = I40E_ERR_TIMEOUT;
180 	u32 sr_reg;
181 
182 	if (offset >= hw->nvm.sr_size) {
183 		hw_dbg(hw, "NVM read error: Offset beyond Shadow RAM limit.\n");
184 		ret_code = I40E_ERR_PARAM;
185 		goto read_nvm_exit;
186 	}
187 
188 	/* Poll the done bit first. */
189 	ret_code = i40e_poll_sr_srctl_done_bit(hw);
190 	if (!ret_code) {
191 		/* Write the address and start reading. */
192 		sr_reg = (u32)(offset << I40E_GLNVM_SRCTL_ADDR_SHIFT) |
193 			 (1 << I40E_GLNVM_SRCTL_START_SHIFT);
194 		wr32(hw, I40E_GLNVM_SRCTL, sr_reg);
195 
196 		/* Poll I40E_GLNVM_SRCTL until the done bit is set. */
197 		ret_code = i40e_poll_sr_srctl_done_bit(hw);
198 		if (!ret_code) {
199 			sr_reg = rd32(hw, I40E_GLNVM_SRDATA);
200 			*data = (u16)((sr_reg &
201 				       I40E_GLNVM_SRDATA_RDDATA_MASK)
202 				    >> I40E_GLNVM_SRDATA_RDDATA_SHIFT);
203 		}
204 	}
205 	if (ret_code)
206 		hw_dbg(hw, "NVM read error: Couldn't access Shadow RAM address: 0x%x\n",
207 			  offset);
208 
209 read_nvm_exit:
210 	return ret_code;
211 }
212 
213 /**
214  *  i40e_read_nvm_word - Reads Shadow RAM word.
215  *  @hw: pointer to the HW structure.
216  *  @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
217  *  @data: word read from the Shadow RAM.
218  *
219  *  Reads 16 bit word from the Shadow RAM. Each read is preceded
220  *  with the NVM ownership taking and followed by the release.
221  **/
222 i40e_status i40e_read_nvm_word(struct i40e_hw *hw, u16 offset,
223 					 u16 *data)
224 {
225 	i40e_status ret_code = 0;
226 
227 	ret_code = i40e_acquire_nvm(hw, I40E_RESOURCE_READ);
228 	if (!ret_code) {
229 		ret_code = i40e_read_nvm_srctl(hw, offset, data);
230 		i40e_release_nvm(hw);
231 	}
232 
233 	return ret_code;
234 }
235 
236 /**
237  *  i40e_read_nvm_buffer - Reads Shadow RAM buffer.
238  *  @hw: pointer to the HW structure.
239  *  @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF).
240  *  @words: number of words to read (in) &
241  *          number of words read before the NVM ownership timeout (out).
242  *  @data: words read from the Shadow RAM.
243  *
244  *  Reads 16 bit words (data buffer) from the SR using the i40e_read_nvm_srrd()
245  *  method. The buffer read is preceded by the NVM ownership take
246  *  and followed by the release.
247  **/
248 i40e_status i40e_read_nvm_buffer(struct i40e_hw *hw, u16 offset,
249 					   u16 *words, u16 *data)
250 {
251 	i40e_status ret_code = 0;
252 	u16 index, word;
253 	u32 time;
254 
255 	ret_code = i40e_acquire_nvm(hw, I40E_RESOURCE_READ);
256 	if (!ret_code) {
257 		/* Loop thru the selected region. */
258 		for (word = 0; word < *words; word++) {
259 			index = offset + word;
260 			ret_code = i40e_read_nvm_srctl(hw, index, &data[word]);
261 			if (ret_code)
262 				break;
263 			/* Check if we didn't exceeded the semaphore timeout. */
264 			time = rd32(hw, I40E_GLVFGEN_TIMER);
265 			if (time >= hw->nvm.hw_semaphore_timeout) {
266 				ret_code = I40E_ERR_TIMEOUT;
267 				hw_dbg(hw, "NVM read error: timeout.\n");
268 				break;
269 			}
270 		}
271 		/* Update the number of words read from the Shadow RAM. */
272 		*words = word;
273 		/* Release the NVM ownership. */
274 		i40e_release_nvm(hw);
275 	}
276 
277 	return ret_code;
278 }
279 
280 /**
281  *  i40e_calc_nvm_checksum - Calculates and returns the checksum
282  *  @hw: pointer to hardware structure
283  *
284  *  This function calculate SW Checksum that covers the whole 64kB shadow RAM
285  *  except the VPD and PCIe ALT Auto-load modules. The structure and size of VPD
286  *  is customer specific and unknown. Therefore, this function skips all maximum
287  *  possible size of VPD (1kB).
288  **/
289 static i40e_status i40e_calc_nvm_checksum(struct i40e_hw *hw,
290 						    u16 *checksum)
291 {
292 	i40e_status ret_code = 0;
293 	u16 pcie_alt_module = 0;
294 	u16 checksum_local = 0;
295 	u16 vpd_module = 0;
296 	u16 word = 0;
297 	u32 i = 0;
298 
299 	/* read pointer to VPD area */
300 	ret_code = i40e_read_nvm_srctl(hw, I40E_SR_VPD_PTR, &vpd_module);
301 	if (ret_code) {
302 		ret_code = I40E_ERR_NVM_CHECKSUM;
303 		goto i40e_calc_nvm_checksum_exit;
304 	}
305 
306 	/* read pointer to PCIe Alt Auto-load module */
307 	ret_code = i40e_read_nvm_srctl(hw, I40E_SR_PCIE_ALT_AUTO_LOAD_PTR,
308 				       &pcie_alt_module);
309 	if (ret_code) {
310 		ret_code = I40E_ERR_NVM_CHECKSUM;
311 		goto i40e_calc_nvm_checksum_exit;
312 	}
313 
314 	/* Calculate SW checksum that covers the whole 64kB shadow RAM
315 	 * except the VPD and PCIe ALT Auto-load modules
316 	 */
317 	for (i = 0; i < hw->nvm.sr_size; i++) {
318 		/* Skip Checksum word */
319 		if (i == I40E_SR_SW_CHECKSUM_WORD)
320 			i++;
321 		/* Skip VPD module (convert byte size to word count) */
322 		if (i == (u32)vpd_module) {
323 			i += (I40E_SR_VPD_MODULE_MAX_SIZE / 2);
324 			if (i >= hw->nvm.sr_size)
325 				break;
326 		}
327 		/* Skip PCIe ALT module (convert byte size to word count) */
328 		if (i == (u32)pcie_alt_module) {
329 			i += (I40E_SR_PCIE_ALT_MODULE_MAX_SIZE / 2);
330 			if (i >= hw->nvm.sr_size)
331 				break;
332 		}
333 
334 		ret_code = i40e_read_nvm_srctl(hw, (u16)i, &word);
335 		if (ret_code) {
336 			ret_code = I40E_ERR_NVM_CHECKSUM;
337 			goto i40e_calc_nvm_checksum_exit;
338 		}
339 		checksum_local += word;
340 	}
341 
342 	*checksum = (u16)I40E_SR_SW_CHECKSUM_BASE - checksum_local;
343 
344 i40e_calc_nvm_checksum_exit:
345 	return ret_code;
346 }
347 
348 /**
349  *  i40e_validate_nvm_checksum - Validate EEPROM checksum
350  *  @hw: pointer to hardware structure
351  *  @checksum: calculated checksum
352  *
353  *  Performs checksum calculation and validates the NVM SW checksum. If the
354  *  caller does not need checksum, the value can be NULL.
355  **/
356 i40e_status i40e_validate_nvm_checksum(struct i40e_hw *hw,
357 						 u16 *checksum)
358 {
359 	i40e_status ret_code = 0;
360 	u16 checksum_sr = 0;
361 	u16 checksum_local;
362 
363 	ret_code = i40e_acquire_nvm(hw, I40E_RESOURCE_READ);
364 	if (ret_code)
365 		goto i40e_validate_nvm_checksum_exit;
366 
367 	ret_code = i40e_calc_nvm_checksum(hw, &checksum_local);
368 	if (ret_code)
369 		goto i40e_validate_nvm_checksum_free;
370 
371 	/* Do not use i40e_read_nvm_word() because we do not want to take
372 	 * the synchronization semaphores twice here.
373 	 */
374 	i40e_read_nvm_srctl(hw, I40E_SR_SW_CHECKSUM_WORD, &checksum_sr);
375 
376 	/* Verify read checksum from EEPROM is the same as
377 	 * calculated checksum
378 	 */
379 	if (checksum_local != checksum_sr)
380 		ret_code = I40E_ERR_NVM_CHECKSUM;
381 
382 	/* If the user cares, return the calculated checksum */
383 	if (checksum)
384 		*checksum = checksum_local;
385 
386 i40e_validate_nvm_checksum_free:
387 	i40e_release_nvm(hw);
388 
389 i40e_validate_nvm_checksum_exit:
390 	return ret_code;
391 }
392