1 /*
2  * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
3  *
4  * Author:
5  *	Mikko Perttunen <mperttunen@nvidia.com>
6  *
7  * This software is licensed under the terms of the GNU General Public
8  * License version 2, as published by the Free Software Foundation, and
9  * may be copied, distributed, and modified under those terms.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  */
17 
18 #include <linux/clk-provider.h>
19 #include <linux/clk.h>
20 #include <linux/clkdev.h>
21 #include <linux/debugfs.h>
22 #include <linux/delay.h>
23 #include <linux/of_address.h>
24 #include <linux/of_platform.h>
25 #include <linux/platform_device.h>
26 #include <linux/sort.h>
27 #include <linux/string.h>
28 
29 #include <soc/tegra/emc.h>
30 #include <soc/tegra/fuse.h>
31 #include <soc/tegra/mc.h>
32 
33 #define EMC_FBIO_CFG5				0x104
34 #define	EMC_FBIO_CFG5_DRAM_TYPE_MASK		0x3
35 #define	EMC_FBIO_CFG5_DRAM_TYPE_SHIFT		0
36 
37 #define EMC_INTSTATUS				0x0
38 #define EMC_INTSTATUS_CLKCHANGE_COMPLETE	BIT(4)
39 
40 #define EMC_CFG					0xc
41 #define EMC_CFG_DRAM_CLKSTOP_PD			BIT(31)
42 #define EMC_CFG_DRAM_CLKSTOP_SR			BIT(30)
43 #define EMC_CFG_DRAM_ACPD			BIT(29)
44 #define EMC_CFG_DYN_SREF			BIT(28)
45 #define EMC_CFG_PWR_MASK			((0xF << 28) | BIT(18))
46 #define EMC_CFG_DSR_VTTGEN_DRV_EN		BIT(18)
47 
48 #define EMC_REFCTRL				0x20
49 #define EMC_REFCTRL_DEV_SEL_SHIFT		0
50 #define EMC_REFCTRL_ENABLE			BIT(31)
51 
52 #define EMC_TIMING_CONTROL			0x28
53 #define EMC_RC					0x2c
54 #define EMC_RFC					0x30
55 #define EMC_RAS					0x34
56 #define EMC_RP					0x38
57 #define EMC_R2W					0x3c
58 #define EMC_W2R					0x40
59 #define EMC_R2P					0x44
60 #define EMC_W2P					0x48
61 #define EMC_RD_RCD				0x4c
62 #define EMC_WR_RCD				0x50
63 #define EMC_RRD					0x54
64 #define EMC_REXT				0x58
65 #define EMC_WDV					0x5c
66 #define EMC_QUSE				0x60
67 #define EMC_QRST				0x64
68 #define EMC_QSAFE				0x68
69 #define EMC_RDV					0x6c
70 #define EMC_REFRESH				0x70
71 #define EMC_BURST_REFRESH_NUM			0x74
72 #define EMC_PDEX2WR				0x78
73 #define EMC_PDEX2RD				0x7c
74 #define EMC_PCHG2PDEN				0x80
75 #define EMC_ACT2PDEN				0x84
76 #define EMC_AR2PDEN				0x88
77 #define EMC_RW2PDEN				0x8c
78 #define EMC_TXSR				0x90
79 #define EMC_TCKE				0x94
80 #define EMC_TFAW				0x98
81 #define EMC_TRPAB				0x9c
82 #define EMC_TCLKSTABLE				0xa0
83 #define EMC_TCLKSTOP				0xa4
84 #define EMC_TREFBW				0xa8
85 #define EMC_ODT_WRITE				0xb0
86 #define EMC_ODT_READ				0xb4
87 #define EMC_WEXT				0xb8
88 #define EMC_CTT					0xbc
89 #define EMC_RFC_SLR				0xc0
90 #define EMC_MRS_WAIT_CNT2			0xc4
91 
92 #define EMC_MRS_WAIT_CNT			0xc8
93 #define EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT	0
94 #define EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK	\
95 	(0x3FF << EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT)
96 #define EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT	16
97 #define EMC_MRS_WAIT_CNT_LONG_WAIT_MASK		\
98 	(0x3FF << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
99 
100 #define EMC_MRS					0xcc
101 #define EMC_MODE_SET_DLL_RESET			BIT(8)
102 #define EMC_MODE_SET_LONG_CNT			BIT(26)
103 #define EMC_EMRS				0xd0
104 #define EMC_REF					0xd4
105 #define EMC_PRE					0xd8
106 
107 #define EMC_SELF_REF				0xe0
108 #define EMC_SELF_REF_CMD_ENABLED		BIT(0)
109 #define EMC_SELF_REF_DEV_SEL_SHIFT		30
110 
111 #define EMC_MRW					0xe8
112 
113 #define EMC_MRR					0xec
114 #define EMC_MRR_MA_SHIFT			16
115 #define LPDDR2_MR4_TEMP_SHIFT			0
116 
117 #define EMC_XM2DQSPADCTRL3			0xf8
118 #define EMC_FBIO_SPARE				0x100
119 
120 #define EMC_FBIO_CFG6				0x114
121 #define EMC_EMRS2				0x12c
122 #define EMC_MRW2				0x134
123 #define EMC_MRW4				0x13c
124 #define EMC_EINPUT				0x14c
125 #define EMC_EINPUT_DURATION			0x150
126 #define EMC_PUTERM_EXTRA			0x154
127 #define EMC_TCKESR				0x158
128 #define EMC_TPD					0x15c
129 
130 #define EMC_AUTO_CAL_CONFIG			0x2a4
131 #define EMC_AUTO_CAL_CONFIG_AUTO_CAL_START	BIT(31)
132 #define EMC_AUTO_CAL_INTERVAL			0x2a8
133 #define EMC_AUTO_CAL_STATUS			0x2ac
134 #define EMC_AUTO_CAL_STATUS_ACTIVE		BIT(31)
135 #define EMC_STATUS				0x2b4
136 #define EMC_STATUS_TIMING_UPDATE_STALLED	BIT(23)
137 
138 #define EMC_CFG_2				0x2b8
139 #define EMC_CFG_2_MODE_SHIFT			0
140 #define EMC_CFG_2_DIS_STP_OB_CLK_DURING_NON_WR	BIT(6)
141 
142 #define EMC_CFG_DIG_DLL				0x2bc
143 #define EMC_CFG_DIG_DLL_PERIOD			0x2c0
144 #define EMC_RDV_MASK				0x2cc
145 #define EMC_WDV_MASK				0x2d0
146 #define EMC_CTT_DURATION			0x2d8
147 #define EMC_CTT_TERM_CTRL			0x2dc
148 #define EMC_ZCAL_INTERVAL			0x2e0
149 #define EMC_ZCAL_WAIT_CNT			0x2e4
150 
151 #define EMC_ZQ_CAL				0x2ec
152 #define EMC_ZQ_CAL_CMD				BIT(0)
153 #define EMC_ZQ_CAL_LONG				BIT(4)
154 #define EMC_ZQ_CAL_LONG_CMD_DEV0		\
155 	(DRAM_DEV_SEL_0 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
156 #define EMC_ZQ_CAL_LONG_CMD_DEV1		\
157 	(DRAM_DEV_SEL_1 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
158 
159 #define EMC_XM2CMDPADCTRL			0x2f0
160 #define EMC_XM2DQSPADCTRL			0x2f8
161 #define EMC_XM2DQSPADCTRL2			0x2fc
162 #define EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE	BIT(0)
163 #define EMC_XM2DQSPADCTRL2_VREF_ENABLE		BIT(5)
164 #define EMC_XM2DQPADCTRL			0x300
165 #define EMC_XM2DQPADCTRL2			0x304
166 #define EMC_XM2CLKPADCTRL			0x308
167 #define EMC_XM2COMPPADCTRL			0x30c
168 #define EMC_XM2VTTGENPADCTRL			0x310
169 #define EMC_XM2VTTGENPADCTRL2			0x314
170 #define EMC_XM2VTTGENPADCTRL3			0x318
171 #define EMC_XM2DQSPADCTRL4			0x320
172 #define EMC_DLL_XFORM_DQS0			0x328
173 #define EMC_DLL_XFORM_DQS1			0x32c
174 #define EMC_DLL_XFORM_DQS2			0x330
175 #define EMC_DLL_XFORM_DQS3			0x334
176 #define EMC_DLL_XFORM_DQS4			0x338
177 #define EMC_DLL_XFORM_DQS5			0x33c
178 #define EMC_DLL_XFORM_DQS6			0x340
179 #define EMC_DLL_XFORM_DQS7			0x344
180 #define EMC_DLL_XFORM_QUSE0			0x348
181 #define EMC_DLL_XFORM_QUSE1			0x34c
182 #define EMC_DLL_XFORM_QUSE2			0x350
183 #define EMC_DLL_XFORM_QUSE3			0x354
184 #define EMC_DLL_XFORM_QUSE4			0x358
185 #define EMC_DLL_XFORM_QUSE5			0x35c
186 #define EMC_DLL_XFORM_QUSE6			0x360
187 #define EMC_DLL_XFORM_QUSE7			0x364
188 #define EMC_DLL_XFORM_DQ0			0x368
189 #define EMC_DLL_XFORM_DQ1			0x36c
190 #define EMC_DLL_XFORM_DQ2			0x370
191 #define EMC_DLL_XFORM_DQ3			0x374
192 #define EMC_DLI_TRIM_TXDQS0			0x3a8
193 #define EMC_DLI_TRIM_TXDQS1			0x3ac
194 #define EMC_DLI_TRIM_TXDQS2			0x3b0
195 #define EMC_DLI_TRIM_TXDQS3			0x3b4
196 #define EMC_DLI_TRIM_TXDQS4			0x3b8
197 #define EMC_DLI_TRIM_TXDQS5			0x3bc
198 #define EMC_DLI_TRIM_TXDQS6			0x3c0
199 #define EMC_DLI_TRIM_TXDQS7			0x3c4
200 #define EMC_STALL_THEN_EXE_AFTER_CLKCHANGE	0x3cc
201 #define EMC_SEL_DPD_CTRL			0x3d8
202 #define EMC_SEL_DPD_CTRL_DATA_SEL_DPD		BIT(8)
203 #define EMC_SEL_DPD_CTRL_ODT_SEL_DPD		BIT(5)
204 #define EMC_SEL_DPD_CTRL_RESET_SEL_DPD		BIT(4)
205 #define EMC_SEL_DPD_CTRL_CA_SEL_DPD		BIT(3)
206 #define EMC_SEL_DPD_CTRL_CLK_SEL_DPD		BIT(2)
207 #define EMC_SEL_DPD_CTRL_DDR3_MASK	\
208 	((0xf << 2) | BIT(8))
209 #define EMC_SEL_DPD_CTRL_MASK \
210 	((0x3 << 2) | BIT(5) | BIT(8))
211 #define EMC_PRE_REFRESH_REQ_CNT			0x3dc
212 #define EMC_DYN_SELF_REF_CONTROL		0x3e0
213 #define EMC_TXSRDLL				0x3e4
214 #define EMC_CCFIFO_ADDR				0x3e8
215 #define EMC_CCFIFO_DATA				0x3ec
216 #define EMC_CCFIFO_STATUS			0x3f0
217 #define EMC_CDB_CNTL_1				0x3f4
218 #define EMC_CDB_CNTL_2				0x3f8
219 #define EMC_XM2CLKPADCTRL2			0x3fc
220 #define EMC_AUTO_CAL_CONFIG2			0x458
221 #define EMC_AUTO_CAL_CONFIG3			0x45c
222 #define EMC_IBDLY				0x468
223 #define EMC_DLL_XFORM_ADDR0			0x46c
224 #define EMC_DLL_XFORM_ADDR1			0x470
225 #define EMC_DLL_XFORM_ADDR2			0x474
226 #define EMC_DSR_VTTGEN_DRV			0x47c
227 #define EMC_TXDSRVTTGEN				0x480
228 #define EMC_XM2CMDPADCTRL4			0x484
229 #define EMC_XM2CMDPADCTRL5			0x488
230 #define EMC_DLL_XFORM_DQS8			0x4a0
231 #define EMC_DLL_XFORM_DQS9			0x4a4
232 #define EMC_DLL_XFORM_DQS10			0x4a8
233 #define EMC_DLL_XFORM_DQS11			0x4ac
234 #define EMC_DLL_XFORM_DQS12			0x4b0
235 #define EMC_DLL_XFORM_DQS13			0x4b4
236 #define EMC_DLL_XFORM_DQS14			0x4b8
237 #define EMC_DLL_XFORM_DQS15			0x4bc
238 #define EMC_DLL_XFORM_QUSE8			0x4c0
239 #define EMC_DLL_XFORM_QUSE9			0x4c4
240 #define EMC_DLL_XFORM_QUSE10			0x4c8
241 #define EMC_DLL_XFORM_QUSE11			0x4cc
242 #define EMC_DLL_XFORM_QUSE12			0x4d0
243 #define EMC_DLL_XFORM_QUSE13			0x4d4
244 #define EMC_DLL_XFORM_QUSE14			0x4d8
245 #define EMC_DLL_XFORM_QUSE15			0x4dc
246 #define EMC_DLL_XFORM_DQ4			0x4e0
247 #define EMC_DLL_XFORM_DQ5			0x4e4
248 #define EMC_DLL_XFORM_DQ6			0x4e8
249 #define EMC_DLL_XFORM_DQ7			0x4ec
250 #define EMC_DLI_TRIM_TXDQS8			0x520
251 #define EMC_DLI_TRIM_TXDQS9			0x524
252 #define EMC_DLI_TRIM_TXDQS10			0x528
253 #define EMC_DLI_TRIM_TXDQS11			0x52c
254 #define EMC_DLI_TRIM_TXDQS12			0x530
255 #define EMC_DLI_TRIM_TXDQS13			0x534
256 #define EMC_DLI_TRIM_TXDQS14			0x538
257 #define EMC_DLI_TRIM_TXDQS15			0x53c
258 #define EMC_CDB_CNTL_3				0x540
259 #define EMC_XM2DQSPADCTRL5			0x544
260 #define EMC_XM2DQSPADCTRL6			0x548
261 #define EMC_XM2DQPADCTRL3			0x54c
262 #define EMC_DLL_XFORM_ADDR3			0x550
263 #define EMC_DLL_XFORM_ADDR4			0x554
264 #define EMC_DLL_XFORM_ADDR5			0x558
265 #define EMC_CFG_PIPE				0x560
266 #define EMC_QPOP				0x564
267 #define EMC_QUSE_WIDTH				0x568
268 #define EMC_PUTERM_WIDTH			0x56c
269 #define EMC_BGBIAS_CTL0				0x570
270 #define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX BIT(3)
271 #define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_VTTGEN BIT(2)
272 #define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD	BIT(1)
273 #define EMC_PUTERM_ADJ				0x574
274 
275 #define DRAM_DEV_SEL_ALL			0
276 #define DRAM_DEV_SEL_0				(2 << 30)
277 #define DRAM_DEV_SEL_1				(1 << 30)
278 
279 #define EMC_CFG_POWER_FEATURES_MASK		\
280 	(EMC_CFG_DYN_SREF | EMC_CFG_DRAM_ACPD | EMC_CFG_DRAM_CLKSTOP_SR | \
281 	EMC_CFG_DRAM_CLKSTOP_PD | EMC_CFG_DSR_VTTGEN_DRV_EN)
282 #define EMC_REFCTRL_DEV_SEL(n) (((n > 1) ? 0 : 2) << EMC_REFCTRL_DEV_SEL_SHIFT)
283 #define EMC_DRAM_DEV_SEL(n) ((n > 1) ? DRAM_DEV_SEL_ALL : DRAM_DEV_SEL_0)
284 
285 /* Maximum amount of time in us. to wait for changes to become effective */
286 #define EMC_STATUS_UPDATE_TIMEOUT		1000
287 
288 enum emc_dram_type {
289 	DRAM_TYPE_DDR3 = 0,
290 	DRAM_TYPE_DDR1 = 1,
291 	DRAM_TYPE_LPDDR3 = 2,
292 	DRAM_TYPE_DDR2 = 3
293 };
294 
295 enum emc_dll_change {
296 	DLL_CHANGE_NONE,
297 	DLL_CHANGE_ON,
298 	DLL_CHANGE_OFF
299 };
300 
301 static const unsigned long emc_burst_regs[] = {
302 	EMC_RC,
303 	EMC_RFC,
304 	EMC_RFC_SLR,
305 	EMC_RAS,
306 	EMC_RP,
307 	EMC_R2W,
308 	EMC_W2R,
309 	EMC_R2P,
310 	EMC_W2P,
311 	EMC_RD_RCD,
312 	EMC_WR_RCD,
313 	EMC_RRD,
314 	EMC_REXT,
315 	EMC_WEXT,
316 	EMC_WDV,
317 	EMC_WDV_MASK,
318 	EMC_QUSE,
319 	EMC_QUSE_WIDTH,
320 	EMC_IBDLY,
321 	EMC_EINPUT,
322 	EMC_EINPUT_DURATION,
323 	EMC_PUTERM_EXTRA,
324 	EMC_PUTERM_WIDTH,
325 	EMC_PUTERM_ADJ,
326 	EMC_CDB_CNTL_1,
327 	EMC_CDB_CNTL_2,
328 	EMC_CDB_CNTL_3,
329 	EMC_QRST,
330 	EMC_QSAFE,
331 	EMC_RDV,
332 	EMC_RDV_MASK,
333 	EMC_REFRESH,
334 	EMC_BURST_REFRESH_NUM,
335 	EMC_PRE_REFRESH_REQ_CNT,
336 	EMC_PDEX2WR,
337 	EMC_PDEX2RD,
338 	EMC_PCHG2PDEN,
339 	EMC_ACT2PDEN,
340 	EMC_AR2PDEN,
341 	EMC_RW2PDEN,
342 	EMC_TXSR,
343 	EMC_TXSRDLL,
344 	EMC_TCKE,
345 	EMC_TCKESR,
346 	EMC_TPD,
347 	EMC_TFAW,
348 	EMC_TRPAB,
349 	EMC_TCLKSTABLE,
350 	EMC_TCLKSTOP,
351 	EMC_TREFBW,
352 	EMC_FBIO_CFG6,
353 	EMC_ODT_WRITE,
354 	EMC_ODT_READ,
355 	EMC_FBIO_CFG5,
356 	EMC_CFG_DIG_DLL,
357 	EMC_CFG_DIG_DLL_PERIOD,
358 	EMC_DLL_XFORM_DQS0,
359 	EMC_DLL_XFORM_DQS1,
360 	EMC_DLL_XFORM_DQS2,
361 	EMC_DLL_XFORM_DQS3,
362 	EMC_DLL_XFORM_DQS4,
363 	EMC_DLL_XFORM_DQS5,
364 	EMC_DLL_XFORM_DQS6,
365 	EMC_DLL_XFORM_DQS7,
366 	EMC_DLL_XFORM_DQS8,
367 	EMC_DLL_XFORM_DQS9,
368 	EMC_DLL_XFORM_DQS10,
369 	EMC_DLL_XFORM_DQS11,
370 	EMC_DLL_XFORM_DQS12,
371 	EMC_DLL_XFORM_DQS13,
372 	EMC_DLL_XFORM_DQS14,
373 	EMC_DLL_XFORM_DQS15,
374 	EMC_DLL_XFORM_QUSE0,
375 	EMC_DLL_XFORM_QUSE1,
376 	EMC_DLL_XFORM_QUSE2,
377 	EMC_DLL_XFORM_QUSE3,
378 	EMC_DLL_XFORM_QUSE4,
379 	EMC_DLL_XFORM_QUSE5,
380 	EMC_DLL_XFORM_QUSE6,
381 	EMC_DLL_XFORM_QUSE7,
382 	EMC_DLL_XFORM_ADDR0,
383 	EMC_DLL_XFORM_ADDR1,
384 	EMC_DLL_XFORM_ADDR2,
385 	EMC_DLL_XFORM_ADDR3,
386 	EMC_DLL_XFORM_ADDR4,
387 	EMC_DLL_XFORM_ADDR5,
388 	EMC_DLL_XFORM_QUSE8,
389 	EMC_DLL_XFORM_QUSE9,
390 	EMC_DLL_XFORM_QUSE10,
391 	EMC_DLL_XFORM_QUSE11,
392 	EMC_DLL_XFORM_QUSE12,
393 	EMC_DLL_XFORM_QUSE13,
394 	EMC_DLL_XFORM_QUSE14,
395 	EMC_DLL_XFORM_QUSE15,
396 	EMC_DLI_TRIM_TXDQS0,
397 	EMC_DLI_TRIM_TXDQS1,
398 	EMC_DLI_TRIM_TXDQS2,
399 	EMC_DLI_TRIM_TXDQS3,
400 	EMC_DLI_TRIM_TXDQS4,
401 	EMC_DLI_TRIM_TXDQS5,
402 	EMC_DLI_TRIM_TXDQS6,
403 	EMC_DLI_TRIM_TXDQS7,
404 	EMC_DLI_TRIM_TXDQS8,
405 	EMC_DLI_TRIM_TXDQS9,
406 	EMC_DLI_TRIM_TXDQS10,
407 	EMC_DLI_TRIM_TXDQS11,
408 	EMC_DLI_TRIM_TXDQS12,
409 	EMC_DLI_TRIM_TXDQS13,
410 	EMC_DLI_TRIM_TXDQS14,
411 	EMC_DLI_TRIM_TXDQS15,
412 	EMC_DLL_XFORM_DQ0,
413 	EMC_DLL_XFORM_DQ1,
414 	EMC_DLL_XFORM_DQ2,
415 	EMC_DLL_XFORM_DQ3,
416 	EMC_DLL_XFORM_DQ4,
417 	EMC_DLL_XFORM_DQ5,
418 	EMC_DLL_XFORM_DQ6,
419 	EMC_DLL_XFORM_DQ7,
420 	EMC_XM2CMDPADCTRL,
421 	EMC_XM2CMDPADCTRL4,
422 	EMC_XM2CMDPADCTRL5,
423 	EMC_XM2DQPADCTRL2,
424 	EMC_XM2DQPADCTRL3,
425 	EMC_XM2CLKPADCTRL,
426 	EMC_XM2CLKPADCTRL2,
427 	EMC_XM2COMPPADCTRL,
428 	EMC_XM2VTTGENPADCTRL,
429 	EMC_XM2VTTGENPADCTRL2,
430 	EMC_XM2VTTGENPADCTRL3,
431 	EMC_XM2DQSPADCTRL3,
432 	EMC_XM2DQSPADCTRL4,
433 	EMC_XM2DQSPADCTRL5,
434 	EMC_XM2DQSPADCTRL6,
435 	EMC_DSR_VTTGEN_DRV,
436 	EMC_TXDSRVTTGEN,
437 	EMC_FBIO_SPARE,
438 	EMC_ZCAL_WAIT_CNT,
439 	EMC_MRS_WAIT_CNT2,
440 	EMC_CTT,
441 	EMC_CTT_DURATION,
442 	EMC_CFG_PIPE,
443 	EMC_DYN_SELF_REF_CONTROL,
444 	EMC_QPOP
445 };
446 
447 struct emc_timing {
448 	unsigned long rate;
449 
450 	u32 emc_burst_data[ARRAY_SIZE(emc_burst_regs)];
451 
452 	u32 emc_auto_cal_config;
453 	u32 emc_auto_cal_config2;
454 	u32 emc_auto_cal_config3;
455 	u32 emc_auto_cal_interval;
456 	u32 emc_bgbias_ctl0;
457 	u32 emc_cfg;
458 	u32 emc_cfg_2;
459 	u32 emc_ctt_term_ctrl;
460 	u32 emc_mode_1;
461 	u32 emc_mode_2;
462 	u32 emc_mode_4;
463 	u32 emc_mode_reset;
464 	u32 emc_mrs_wait_cnt;
465 	u32 emc_sel_dpd_ctrl;
466 	u32 emc_xm2dqspadctrl2;
467 	u32 emc_zcal_cnt_long;
468 	u32 emc_zcal_interval;
469 };
470 
471 struct tegra_emc {
472 	struct device *dev;
473 
474 	struct tegra_mc *mc;
475 
476 	void __iomem *regs;
477 
478 	enum emc_dram_type dram_type;
479 	unsigned int dram_num;
480 
481 	struct emc_timing last_timing;
482 	struct emc_timing *timings;
483 	unsigned int num_timings;
484 };
485 
486 /* Timing change sequence functions */
487 
488 static void emc_ccfifo_writel(struct tegra_emc *emc, u32 value,
489 			      unsigned long offset)
490 {
491 	writel(value, emc->regs + EMC_CCFIFO_DATA);
492 	writel(offset, emc->regs + EMC_CCFIFO_ADDR);
493 }
494 
495 static void emc_seq_update_timing(struct tegra_emc *emc)
496 {
497 	unsigned int i;
498 	u32 value;
499 
500 	writel(1, emc->regs + EMC_TIMING_CONTROL);
501 
502 	for (i = 0; i < EMC_STATUS_UPDATE_TIMEOUT; ++i) {
503 		value = readl(emc->regs + EMC_STATUS);
504 		if ((value & EMC_STATUS_TIMING_UPDATE_STALLED) == 0)
505 			return;
506 		udelay(1);
507 	}
508 
509 	dev_err(emc->dev, "timing update timed out\n");
510 }
511 
512 static void emc_seq_disable_auto_cal(struct tegra_emc *emc)
513 {
514 	unsigned int i;
515 	u32 value;
516 
517 	writel(0, emc->regs + EMC_AUTO_CAL_INTERVAL);
518 
519 	for (i = 0; i < EMC_STATUS_UPDATE_TIMEOUT; ++i) {
520 		value = readl(emc->regs + EMC_AUTO_CAL_STATUS);
521 		if ((value & EMC_AUTO_CAL_STATUS_ACTIVE) == 0)
522 			return;
523 		udelay(1);
524 	}
525 
526 	dev_err(emc->dev, "auto cal disable timed out\n");
527 }
528 
529 static void emc_seq_wait_clkchange(struct tegra_emc *emc)
530 {
531 	unsigned int i;
532 	u32 value;
533 
534 	for (i = 0; i < EMC_STATUS_UPDATE_TIMEOUT; ++i) {
535 		value = readl(emc->regs + EMC_INTSTATUS);
536 		if (value & EMC_INTSTATUS_CLKCHANGE_COMPLETE)
537 			return;
538 		udelay(1);
539 	}
540 
541 	dev_err(emc->dev, "clock change timed out\n");
542 }
543 
544 static struct emc_timing *tegra_emc_find_timing(struct tegra_emc *emc,
545 						unsigned long rate)
546 {
547 	struct emc_timing *timing = NULL;
548 	unsigned int i;
549 
550 	for (i = 0; i < emc->num_timings; i++) {
551 		if (emc->timings[i].rate == rate) {
552 			timing = &emc->timings[i];
553 			break;
554 		}
555 	}
556 
557 	if (!timing) {
558 		dev_err(emc->dev, "no timing for rate %lu\n", rate);
559 		return NULL;
560 	}
561 
562 	return timing;
563 }
564 
565 int tegra_emc_prepare_timing_change(struct tegra_emc *emc,
566 				    unsigned long rate)
567 {
568 	struct emc_timing *timing = tegra_emc_find_timing(emc, rate);
569 	struct emc_timing *last = &emc->last_timing;
570 	enum emc_dll_change dll_change;
571 	unsigned int pre_wait = 0;
572 	u32 val, val2, mask;
573 	bool update = false;
574 	unsigned int i;
575 
576 	if (!timing)
577 		return -ENOENT;
578 
579 	if ((last->emc_mode_1 & 0x1) == (timing->emc_mode_1 & 0x1))
580 		dll_change = DLL_CHANGE_NONE;
581 	else if (timing->emc_mode_1 & 0x1)
582 		dll_change = DLL_CHANGE_ON;
583 	else
584 		dll_change = DLL_CHANGE_OFF;
585 
586 	/* Clear CLKCHANGE_COMPLETE interrupts */
587 	writel(EMC_INTSTATUS_CLKCHANGE_COMPLETE, emc->regs + EMC_INTSTATUS);
588 
589 	/* Disable dynamic self-refresh */
590 	val = readl(emc->regs + EMC_CFG);
591 	if (val & EMC_CFG_PWR_MASK) {
592 		val &= ~EMC_CFG_POWER_FEATURES_MASK;
593 		writel(val, emc->regs + EMC_CFG);
594 
595 		pre_wait = 5;
596 	}
597 
598 	/* Disable SEL_DPD_CTRL for clock change */
599 	if (emc->dram_type == DRAM_TYPE_DDR3)
600 		mask = EMC_SEL_DPD_CTRL_DDR3_MASK;
601 	else
602 		mask = EMC_SEL_DPD_CTRL_MASK;
603 
604 	val = readl(emc->regs + EMC_SEL_DPD_CTRL);
605 	if (val & mask) {
606 		val &= ~mask;
607 		writel(val, emc->regs + EMC_SEL_DPD_CTRL);
608 	}
609 
610 	/* Prepare DQ/DQS for clock change */
611 	val = readl(emc->regs + EMC_BGBIAS_CTL0);
612 	val2 = last->emc_bgbias_ctl0;
613 	if (!(timing->emc_bgbias_ctl0 &
614 	      EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX) &&
615 	    (val & EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX)) {
616 		val2 &= ~EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX;
617 		update = true;
618 	}
619 
620 	if ((val & EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD) ||
621 	    (val & EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_VTTGEN)) {
622 		update = true;
623 	}
624 
625 	if (update) {
626 		writel(val2, emc->regs + EMC_BGBIAS_CTL0);
627 		if (pre_wait < 5)
628 			pre_wait = 5;
629 	}
630 
631 	update = false;
632 	val = readl(emc->regs + EMC_XM2DQSPADCTRL2);
633 	if (timing->emc_xm2dqspadctrl2 & EMC_XM2DQSPADCTRL2_VREF_ENABLE &&
634 	    !(val & EMC_XM2DQSPADCTRL2_VREF_ENABLE)) {
635 		val |= EMC_XM2DQSPADCTRL2_VREF_ENABLE;
636 		update = true;
637 	}
638 
639 	if (timing->emc_xm2dqspadctrl2 & EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE &&
640 	    !(val & EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE)) {
641 		val |= EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE;
642 		update = true;
643 	}
644 
645 	if (update) {
646 		writel(val, emc->regs + EMC_XM2DQSPADCTRL2);
647 		if (pre_wait < 30)
648 			pre_wait = 30;
649 	}
650 
651 	/* Wait to settle */
652 	if (pre_wait) {
653 		emc_seq_update_timing(emc);
654 		udelay(pre_wait);
655 	}
656 
657 	/* Program CTT_TERM control */
658 	if (last->emc_ctt_term_ctrl != timing->emc_ctt_term_ctrl) {
659 		emc_seq_disable_auto_cal(emc);
660 		writel(timing->emc_ctt_term_ctrl,
661 		       emc->regs + EMC_CTT_TERM_CTRL);
662 		emc_seq_update_timing(emc);
663 	}
664 
665 	/* Program burst shadow registers */
666 	for (i = 0; i < ARRAY_SIZE(timing->emc_burst_data); ++i)
667 		writel(timing->emc_burst_data[i],
668 		       emc->regs + emc_burst_regs[i]);
669 
670 	writel(timing->emc_xm2dqspadctrl2, emc->regs + EMC_XM2DQSPADCTRL2);
671 	writel(timing->emc_zcal_interval, emc->regs + EMC_ZCAL_INTERVAL);
672 
673 	tegra_mc_write_emem_configuration(emc->mc, timing->rate);
674 
675 	val = timing->emc_cfg & ~EMC_CFG_POWER_FEATURES_MASK;
676 	emc_ccfifo_writel(emc, val, EMC_CFG);
677 
678 	/* Program AUTO_CAL_CONFIG */
679 	if (timing->emc_auto_cal_config2 != last->emc_auto_cal_config2)
680 		emc_ccfifo_writel(emc, timing->emc_auto_cal_config2,
681 				  EMC_AUTO_CAL_CONFIG2);
682 
683 	if (timing->emc_auto_cal_config3 != last->emc_auto_cal_config3)
684 		emc_ccfifo_writel(emc, timing->emc_auto_cal_config3,
685 				  EMC_AUTO_CAL_CONFIG3);
686 
687 	if (timing->emc_auto_cal_config != last->emc_auto_cal_config) {
688 		val = timing->emc_auto_cal_config;
689 		val &= EMC_AUTO_CAL_CONFIG_AUTO_CAL_START;
690 		emc_ccfifo_writel(emc, val, EMC_AUTO_CAL_CONFIG);
691 	}
692 
693 	/* DDR3: predict MRS long wait count */
694 	if (emc->dram_type == DRAM_TYPE_DDR3 &&
695 	    dll_change == DLL_CHANGE_ON) {
696 		u32 cnt = 512;
697 
698 		if (timing->emc_zcal_interval != 0 &&
699 		    last->emc_zcal_interval == 0)
700 			cnt -= emc->dram_num * 256;
701 
702 		val = (timing->emc_mrs_wait_cnt
703 			& EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK)
704 			>> EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT;
705 		if (cnt < val)
706 			cnt = val;
707 
708 		val = timing->emc_mrs_wait_cnt
709 			& ~EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
710 		val |= (cnt << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
711 			& EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
712 
713 		writel(val, emc->regs + EMC_MRS_WAIT_CNT);
714 	}
715 
716 	val = timing->emc_cfg_2;
717 	val &= ~EMC_CFG_2_DIS_STP_OB_CLK_DURING_NON_WR;
718 	emc_ccfifo_writel(emc, val, EMC_CFG_2);
719 
720 	/* DDR3: Turn off DLL and enter self-refresh */
721 	if (emc->dram_type == DRAM_TYPE_DDR3 && dll_change == DLL_CHANGE_OFF)
722 		emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_EMRS);
723 
724 	/* Disable refresh controller */
725 	emc_ccfifo_writel(emc, EMC_REFCTRL_DEV_SEL(emc->dram_num),
726 			  EMC_REFCTRL);
727 	if (emc->dram_type == DRAM_TYPE_DDR3)
728 		emc_ccfifo_writel(emc, EMC_DRAM_DEV_SEL(emc->dram_num) |
729 				       EMC_SELF_REF_CMD_ENABLED,
730 				  EMC_SELF_REF);
731 
732 	/* Flow control marker */
733 	emc_ccfifo_writel(emc, 1, EMC_STALL_THEN_EXE_AFTER_CLKCHANGE);
734 
735 	/* DDR3: Exit self-refresh */
736 	if (emc->dram_type == DRAM_TYPE_DDR3)
737 		emc_ccfifo_writel(emc, EMC_DRAM_DEV_SEL(emc->dram_num),
738 				  EMC_SELF_REF);
739 	emc_ccfifo_writel(emc, EMC_REFCTRL_DEV_SEL(emc->dram_num) |
740 			       EMC_REFCTRL_ENABLE,
741 			  EMC_REFCTRL);
742 
743 	/* Set DRAM mode registers */
744 	if (emc->dram_type == DRAM_TYPE_DDR3) {
745 		if (timing->emc_mode_1 != last->emc_mode_1)
746 			emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_EMRS);
747 		if (timing->emc_mode_2 != last->emc_mode_2)
748 			emc_ccfifo_writel(emc, timing->emc_mode_2, EMC_EMRS2);
749 
750 		if ((timing->emc_mode_reset != last->emc_mode_reset) ||
751 		    dll_change == DLL_CHANGE_ON) {
752 			val = timing->emc_mode_reset;
753 			if (dll_change == DLL_CHANGE_ON) {
754 				val |= EMC_MODE_SET_DLL_RESET;
755 				val |= EMC_MODE_SET_LONG_CNT;
756 			} else {
757 				val &= ~EMC_MODE_SET_DLL_RESET;
758 			}
759 			emc_ccfifo_writel(emc, val, EMC_MRS);
760 		}
761 	} else {
762 		if (timing->emc_mode_2 != last->emc_mode_2)
763 			emc_ccfifo_writel(emc, timing->emc_mode_2, EMC_MRW2);
764 		if (timing->emc_mode_1 != last->emc_mode_1)
765 			emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_MRW);
766 		if (timing->emc_mode_4 != last->emc_mode_4)
767 			emc_ccfifo_writel(emc, timing->emc_mode_4, EMC_MRW4);
768 	}
769 
770 	/*  Issue ZCAL command if turning ZCAL on */
771 	if (timing->emc_zcal_interval != 0 && last->emc_zcal_interval == 0) {
772 		emc_ccfifo_writel(emc, EMC_ZQ_CAL_LONG_CMD_DEV0, EMC_ZQ_CAL);
773 		if (emc->dram_num > 1)
774 			emc_ccfifo_writel(emc, EMC_ZQ_CAL_LONG_CMD_DEV1,
775 					  EMC_ZQ_CAL);
776 	}
777 
778 	/*  Write to RO register to remove stall after change */
779 	emc_ccfifo_writel(emc, 0, EMC_CCFIFO_STATUS);
780 
781 	if (timing->emc_cfg_2 & EMC_CFG_2_DIS_STP_OB_CLK_DURING_NON_WR)
782 		emc_ccfifo_writel(emc, timing->emc_cfg_2, EMC_CFG_2);
783 
784 	/* Disable AUTO_CAL for clock change */
785 	emc_seq_disable_auto_cal(emc);
786 
787 	/* Read register to wait until programming has settled */
788 	readl(emc->regs + EMC_INTSTATUS);
789 
790 	return 0;
791 }
792 
793 void tegra_emc_complete_timing_change(struct tegra_emc *emc,
794 				      unsigned long rate)
795 {
796 	struct emc_timing *timing = tegra_emc_find_timing(emc, rate);
797 	struct emc_timing *last = &emc->last_timing;
798 	u32 val;
799 
800 	if (!timing)
801 		return;
802 
803 	/* Wait until the state machine has settled */
804 	emc_seq_wait_clkchange(emc);
805 
806 	/* Restore AUTO_CAL */
807 	if (timing->emc_ctt_term_ctrl != last->emc_ctt_term_ctrl)
808 		writel(timing->emc_auto_cal_interval,
809 		       emc->regs + EMC_AUTO_CAL_INTERVAL);
810 
811 	/* Restore dynamic self-refresh */
812 	if (timing->emc_cfg & EMC_CFG_PWR_MASK)
813 		writel(timing->emc_cfg, emc->regs + EMC_CFG);
814 
815 	/* Set ZCAL wait count */
816 	writel(timing->emc_zcal_cnt_long, emc->regs + EMC_ZCAL_WAIT_CNT);
817 
818 	/* LPDDR3: Turn off BGBIAS if low frequency */
819 	if (emc->dram_type == DRAM_TYPE_LPDDR3 &&
820 	    timing->emc_bgbias_ctl0 &
821 	      EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX) {
822 		val = timing->emc_bgbias_ctl0;
823 		val |= EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_VTTGEN;
824 		val |= EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD;
825 		writel(val, emc->regs + EMC_BGBIAS_CTL0);
826 	} else {
827 		if (emc->dram_type == DRAM_TYPE_DDR3 &&
828 		    readl(emc->regs + EMC_BGBIAS_CTL0) !=
829 		      timing->emc_bgbias_ctl0) {
830 			writel(timing->emc_bgbias_ctl0,
831 			       emc->regs + EMC_BGBIAS_CTL0);
832 		}
833 
834 		writel(timing->emc_auto_cal_interval,
835 		       emc->regs + EMC_AUTO_CAL_INTERVAL);
836 	}
837 
838 	/* Wait for timing to settle */
839 	udelay(2);
840 
841 	/* Reprogram SEL_DPD_CTRL */
842 	writel(timing->emc_sel_dpd_ctrl, emc->regs + EMC_SEL_DPD_CTRL);
843 	emc_seq_update_timing(emc);
844 
845 	emc->last_timing = *timing;
846 }
847 
848 /* Initialization and deinitialization */
849 
850 static void emc_read_current_timing(struct tegra_emc *emc,
851 				    struct emc_timing *timing)
852 {
853 	unsigned int i;
854 
855 	for (i = 0; i < ARRAY_SIZE(emc_burst_regs); ++i)
856 		timing->emc_burst_data[i] =
857 			readl(emc->regs + emc_burst_regs[i]);
858 
859 	timing->emc_cfg = readl(emc->regs + EMC_CFG);
860 
861 	timing->emc_auto_cal_interval = 0;
862 	timing->emc_zcal_cnt_long = 0;
863 	timing->emc_mode_1 = 0;
864 	timing->emc_mode_2 = 0;
865 	timing->emc_mode_4 = 0;
866 	timing->emc_mode_reset = 0;
867 }
868 
869 static int emc_init(struct tegra_emc *emc)
870 {
871 	emc->dram_type = readl(emc->regs + EMC_FBIO_CFG5);
872 	emc->dram_type &= EMC_FBIO_CFG5_DRAM_TYPE_MASK;
873 	emc->dram_type >>= EMC_FBIO_CFG5_DRAM_TYPE_SHIFT;
874 
875 	emc->dram_num = tegra_mc_get_emem_device_count(emc->mc);
876 
877 	emc_read_current_timing(emc, &emc->last_timing);
878 
879 	return 0;
880 }
881 
882 static int load_one_timing_from_dt(struct tegra_emc *emc,
883 				   struct emc_timing *timing,
884 				   struct device_node *node)
885 {
886 	u32 value;
887 	int err;
888 
889 	err = of_property_read_u32(node, "clock-frequency", &value);
890 	if (err) {
891 		dev_err(emc->dev, "timing %s: failed to read rate: %d\n",
892 			node->name, err);
893 		return err;
894 	}
895 
896 	timing->rate = value;
897 
898 	err = of_property_read_u32_array(node, "nvidia,emc-configuration",
899 					 timing->emc_burst_data,
900 					 ARRAY_SIZE(timing->emc_burst_data));
901 	if (err) {
902 		dev_err(emc->dev,
903 			"timing %s: failed to read emc burst data: %d\n",
904 			node->name, err);
905 		return err;
906 	}
907 
908 #define EMC_READ_PROP(prop, dtprop) { \
909 	err = of_property_read_u32(node, dtprop, &timing->prop); \
910 	if (err) { \
911 		dev_err(emc->dev, "timing %s: failed to read " #prop ": %d\n", \
912 			node->name, err); \
913 		return err; \
914 	} \
915 }
916 
917 	EMC_READ_PROP(emc_auto_cal_config, "nvidia,emc-auto-cal-config")
918 	EMC_READ_PROP(emc_auto_cal_config2, "nvidia,emc-auto-cal-config2")
919 	EMC_READ_PROP(emc_auto_cal_config3, "nvidia,emc-auto-cal-config3")
920 	EMC_READ_PROP(emc_auto_cal_interval, "nvidia,emc-auto-cal-interval")
921 	EMC_READ_PROP(emc_bgbias_ctl0, "nvidia,emc-bgbias-ctl0")
922 	EMC_READ_PROP(emc_cfg, "nvidia,emc-cfg")
923 	EMC_READ_PROP(emc_cfg_2, "nvidia,emc-cfg-2")
924 	EMC_READ_PROP(emc_ctt_term_ctrl, "nvidia,emc-ctt-term-ctrl")
925 	EMC_READ_PROP(emc_mode_1, "nvidia,emc-mode-1")
926 	EMC_READ_PROP(emc_mode_2, "nvidia,emc-mode-2")
927 	EMC_READ_PROP(emc_mode_4, "nvidia,emc-mode-4")
928 	EMC_READ_PROP(emc_mode_reset, "nvidia,emc-mode-reset")
929 	EMC_READ_PROP(emc_mrs_wait_cnt, "nvidia,emc-mrs-wait-cnt")
930 	EMC_READ_PROP(emc_sel_dpd_ctrl, "nvidia,emc-sel-dpd-ctrl")
931 	EMC_READ_PROP(emc_xm2dqspadctrl2, "nvidia,emc-xm2dqspadctrl2")
932 	EMC_READ_PROP(emc_zcal_cnt_long, "nvidia,emc-zcal-cnt-long")
933 	EMC_READ_PROP(emc_zcal_interval, "nvidia,emc-zcal-interval")
934 
935 #undef EMC_READ_PROP
936 
937 	return 0;
938 }
939 
940 static int cmp_timings(const void *_a, const void *_b)
941 {
942 	const struct emc_timing *a = _a;
943 	const struct emc_timing *b = _b;
944 
945 	if (a->rate < b->rate)
946 		return -1;
947 	else if (a->rate == b->rate)
948 		return 0;
949 	else
950 		return 1;
951 }
952 
953 static int tegra_emc_load_timings_from_dt(struct tegra_emc *emc,
954 					  struct device_node *node)
955 {
956 	int child_count = of_get_child_count(node);
957 	struct device_node *child;
958 	struct emc_timing *timing;
959 	unsigned int i = 0;
960 	int err;
961 
962 	emc->timings = devm_kcalloc(emc->dev, child_count, sizeof(*timing),
963 				    GFP_KERNEL);
964 	if (!emc->timings)
965 		return -ENOMEM;
966 
967 	emc->num_timings = child_count;
968 
969 	for_each_child_of_node(node, child) {
970 		timing = &emc->timings[i++];
971 
972 		err = load_one_timing_from_dt(emc, timing, child);
973 		if (err)
974 			return err;
975 	}
976 
977 	sort(emc->timings, emc->num_timings, sizeof(*timing), cmp_timings,
978 	     NULL);
979 
980 	return 0;
981 }
982 
983 static const struct of_device_id tegra_emc_of_match[] = {
984 	{ .compatible = "nvidia,tegra124-emc" },
985 	{}
986 };
987 
988 static struct device_node *
989 tegra_emc_find_node_by_ram_code(struct device_node *node, u32 ram_code)
990 {
991 	struct device_node *np;
992 	int err;
993 
994 	for_each_child_of_node(node, np) {
995 		u32 value;
996 
997 		err = of_property_read_u32(np, "nvidia,ram-code", &value);
998 		if (err || (value != ram_code)) {
999 			of_node_put(np);
1000 			continue;
1001 		}
1002 
1003 		return np;
1004 	}
1005 
1006 	return NULL;
1007 }
1008 
1009 /* Debugfs entry */
1010 
1011 static int emc_debug_rate_get(void *data, u64 *rate)
1012 {
1013 	struct clk *c = data;
1014 
1015 	*rate = clk_get_rate(c);
1016 
1017 	return 0;
1018 }
1019 
1020 static int emc_debug_rate_set(void *data, u64 rate)
1021 {
1022 	struct clk *c = data;
1023 
1024 	return clk_set_rate(c, rate);
1025 }
1026 
1027 DEFINE_SIMPLE_ATTRIBUTE(emc_debug_rate_fops, emc_debug_rate_get,
1028 			emc_debug_rate_set, "%lld\n");
1029 
1030 static int emc_debug_supported_rates_show(struct seq_file *s, void *data)
1031 {
1032 	struct tegra_emc *emc = s->private;
1033 	const char *prefix = "";
1034 	unsigned int i;
1035 
1036 	for (i = 0; i < emc->num_timings; i++) {
1037 		struct emc_timing *timing = &emc->timings[i];
1038 
1039 		seq_printf(s, "%s%lu", prefix, timing->rate);
1040 
1041 		prefix = " ";
1042 	}
1043 
1044 	seq_puts(s, "\n");
1045 
1046 	return 0;
1047 }
1048 
1049 static int emc_debug_supported_rates_open(struct inode *inode,
1050 					  struct file *file)
1051 {
1052 	return single_open(file, emc_debug_supported_rates_show,
1053 			   inode->i_private);
1054 }
1055 
1056 static const struct file_operations emc_debug_supported_rates_fops = {
1057 	.open = emc_debug_supported_rates_open,
1058 	.read = seq_read,
1059 	.llseek = seq_lseek,
1060 	.release = single_release,
1061 };
1062 
1063 static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc)
1064 {
1065 	struct dentry *root, *file;
1066 	struct clk *clk;
1067 
1068 	root = debugfs_create_dir("emc", NULL);
1069 	if (!root) {
1070 		dev_err(dev, "failed to create debugfs directory\n");
1071 		return;
1072 	}
1073 
1074 	clk = clk_get_sys("tegra-clk-debug", "emc");
1075 	if (IS_ERR(clk)) {
1076 		dev_err(dev, "failed to get debug clock: %ld\n", PTR_ERR(clk));
1077 		return;
1078 	}
1079 
1080 	file = debugfs_create_file("rate", S_IRUGO | S_IWUSR, root, clk,
1081 				   &emc_debug_rate_fops);
1082 	if (!file)
1083 		dev_err(dev, "failed to create debugfs entry\n");
1084 
1085 	file = debugfs_create_file("supported_rates", S_IRUGO, root, emc,
1086 				   &emc_debug_supported_rates_fops);
1087 	if (!file)
1088 		dev_err(dev, "failed to create debugfs entry\n");
1089 }
1090 
1091 static int tegra_emc_probe(struct platform_device *pdev)
1092 {
1093 	struct platform_device *mc;
1094 	struct device_node *np;
1095 	struct tegra_emc *emc;
1096 	struct resource *res;
1097 	u32 ram_code;
1098 	int err;
1099 
1100 	emc = devm_kzalloc(&pdev->dev, sizeof(*emc), GFP_KERNEL);
1101 	if (!emc)
1102 		return -ENOMEM;
1103 
1104 	emc->dev = &pdev->dev;
1105 
1106 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1107 	emc->regs = devm_ioremap_resource(&pdev->dev, res);
1108 	if (IS_ERR(emc->regs))
1109 		return PTR_ERR(emc->regs);
1110 
1111 	np = of_parse_phandle(pdev->dev.of_node, "nvidia,memory-controller", 0);
1112 	if (!np) {
1113 		dev_err(&pdev->dev, "could not get memory controller\n");
1114 		return -ENOENT;
1115 	}
1116 
1117 	mc = of_find_device_by_node(np);
1118 	if (!mc)
1119 		return -ENOENT;
1120 
1121 	of_node_put(np);
1122 
1123 	emc->mc = platform_get_drvdata(mc);
1124 	if (!emc->mc)
1125 		return -EPROBE_DEFER;
1126 
1127 	ram_code = tegra_read_ram_code();
1128 
1129 	np = tegra_emc_find_node_by_ram_code(pdev->dev.of_node, ram_code);
1130 	if (!np) {
1131 		dev_err(&pdev->dev,
1132 			"no memory timings for RAM code %u found in DT\n",
1133 			ram_code);
1134 		return -ENOENT;
1135 	}
1136 
1137 	err = tegra_emc_load_timings_from_dt(emc, np);
1138 
1139 	of_node_put(np);
1140 
1141 	if (err)
1142 		return err;
1143 
1144 	if (emc->num_timings == 0) {
1145 		dev_err(&pdev->dev,
1146 			"no memory timings for RAM code %u registered\n",
1147 			ram_code);
1148 		return -ENOENT;
1149 	}
1150 
1151 	err = emc_init(emc);
1152 	if (err) {
1153 		dev_err(&pdev->dev, "EMC initialization failed: %d\n", err);
1154 		return err;
1155 	}
1156 
1157 	platform_set_drvdata(pdev, emc);
1158 
1159 	if (IS_ENABLED(CONFIG_DEBUG_FS))
1160 		emc_debugfs_init(&pdev->dev, emc);
1161 
1162 	return 0;
1163 };
1164 
1165 static struct platform_driver tegra_emc_driver = {
1166 	.probe = tegra_emc_probe,
1167 	.driver = {
1168 		.name = "tegra-emc",
1169 		.of_match_table = tegra_emc_of_match,
1170 		.suppress_bind_attrs = true,
1171 	},
1172 };
1173 
1174 static int tegra_emc_init(void)
1175 {
1176 	return platform_driver_register(&tegra_emc_driver);
1177 }
1178 subsys_initcall(tegra_emc_init);
1179