xref: /linux/drivers/memory/tegra/tegra124-emc.c (revision 141267bf)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
4  *
5  * Author:
6  *	Mikko Perttunen <mperttunen@nvidia.com>
7  */
8 
9 #include <linux/clk-provider.h>
10 #include <linux/clk.h>
11 #include <linux/clkdev.h>
12 #include <linux/debugfs.h>
13 #include <linux/delay.h>
14 #include <linux/io.h>
15 #include <linux/of_address.h>
16 #include <linux/of_platform.h>
17 #include <linux/platform_device.h>
18 #include <linux/sort.h>
19 #include <linux/string.h>
20 
21 #include <soc/tegra/emc.h>
22 #include <soc/tegra/fuse.h>
23 #include <soc/tegra/mc.h>
24 
25 #define EMC_FBIO_CFG5				0x104
26 #define	EMC_FBIO_CFG5_DRAM_TYPE_MASK		0x3
27 #define	EMC_FBIO_CFG5_DRAM_TYPE_SHIFT		0
28 
29 #define EMC_INTSTATUS				0x0
30 #define EMC_INTSTATUS_CLKCHANGE_COMPLETE	BIT(4)
31 
32 #define EMC_CFG					0xc
33 #define EMC_CFG_DRAM_CLKSTOP_PD			BIT(31)
34 #define EMC_CFG_DRAM_CLKSTOP_SR			BIT(30)
35 #define EMC_CFG_DRAM_ACPD			BIT(29)
36 #define EMC_CFG_DYN_SREF			BIT(28)
37 #define EMC_CFG_PWR_MASK			((0xF << 28) | BIT(18))
38 #define EMC_CFG_DSR_VTTGEN_DRV_EN		BIT(18)
39 
40 #define EMC_REFCTRL				0x20
41 #define EMC_REFCTRL_DEV_SEL_SHIFT		0
42 #define EMC_REFCTRL_ENABLE			BIT(31)
43 
44 #define EMC_TIMING_CONTROL			0x28
45 #define EMC_RC					0x2c
46 #define EMC_RFC					0x30
47 #define EMC_RAS					0x34
48 #define EMC_RP					0x38
49 #define EMC_R2W					0x3c
50 #define EMC_W2R					0x40
51 #define EMC_R2P					0x44
52 #define EMC_W2P					0x48
53 #define EMC_RD_RCD				0x4c
54 #define EMC_WR_RCD				0x50
55 #define EMC_RRD					0x54
56 #define EMC_REXT				0x58
57 #define EMC_WDV					0x5c
58 #define EMC_QUSE				0x60
59 #define EMC_QRST				0x64
60 #define EMC_QSAFE				0x68
61 #define EMC_RDV					0x6c
62 #define EMC_REFRESH				0x70
63 #define EMC_BURST_REFRESH_NUM			0x74
64 #define EMC_PDEX2WR				0x78
65 #define EMC_PDEX2RD				0x7c
66 #define EMC_PCHG2PDEN				0x80
67 #define EMC_ACT2PDEN				0x84
68 #define EMC_AR2PDEN				0x88
69 #define EMC_RW2PDEN				0x8c
70 #define EMC_TXSR				0x90
71 #define EMC_TCKE				0x94
72 #define EMC_TFAW				0x98
73 #define EMC_TRPAB				0x9c
74 #define EMC_TCLKSTABLE				0xa0
75 #define EMC_TCLKSTOP				0xa4
76 #define EMC_TREFBW				0xa8
77 #define EMC_ODT_WRITE				0xb0
78 #define EMC_ODT_READ				0xb4
79 #define EMC_WEXT				0xb8
80 #define EMC_CTT					0xbc
81 #define EMC_RFC_SLR				0xc0
82 #define EMC_MRS_WAIT_CNT2			0xc4
83 
84 #define EMC_MRS_WAIT_CNT			0xc8
85 #define EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT	0
86 #define EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK	\
87 	(0x3FF << EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT)
88 #define EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT	16
89 #define EMC_MRS_WAIT_CNT_LONG_WAIT_MASK		\
90 	(0x3FF << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
91 
92 #define EMC_MRS					0xcc
93 #define EMC_MODE_SET_DLL_RESET			BIT(8)
94 #define EMC_MODE_SET_LONG_CNT			BIT(26)
95 #define EMC_EMRS				0xd0
96 #define EMC_REF					0xd4
97 #define EMC_PRE					0xd8
98 
99 #define EMC_SELF_REF				0xe0
100 #define EMC_SELF_REF_CMD_ENABLED		BIT(0)
101 #define EMC_SELF_REF_DEV_SEL_SHIFT		30
102 
103 #define EMC_MRW					0xe8
104 
105 #define EMC_MRR					0xec
106 #define EMC_MRR_MA_SHIFT			16
107 #define LPDDR2_MR4_TEMP_SHIFT			0
108 
109 #define EMC_XM2DQSPADCTRL3			0xf8
110 #define EMC_FBIO_SPARE				0x100
111 
112 #define EMC_FBIO_CFG6				0x114
113 #define EMC_EMRS2				0x12c
114 #define EMC_MRW2				0x134
115 #define EMC_MRW4				0x13c
116 #define EMC_EINPUT				0x14c
117 #define EMC_EINPUT_DURATION			0x150
118 #define EMC_PUTERM_EXTRA			0x154
119 #define EMC_TCKESR				0x158
120 #define EMC_TPD					0x15c
121 
122 #define EMC_AUTO_CAL_CONFIG			0x2a4
123 #define EMC_AUTO_CAL_CONFIG_AUTO_CAL_START	BIT(31)
124 #define EMC_AUTO_CAL_INTERVAL			0x2a8
125 #define EMC_AUTO_CAL_STATUS			0x2ac
126 #define EMC_AUTO_CAL_STATUS_ACTIVE		BIT(31)
127 #define EMC_STATUS				0x2b4
128 #define EMC_STATUS_TIMING_UPDATE_STALLED	BIT(23)
129 
130 #define EMC_CFG_2				0x2b8
131 #define EMC_CFG_2_MODE_SHIFT			0
132 #define EMC_CFG_2_DIS_STP_OB_CLK_DURING_NON_WR	BIT(6)
133 
134 #define EMC_CFG_DIG_DLL				0x2bc
135 #define EMC_CFG_DIG_DLL_PERIOD			0x2c0
136 #define EMC_RDV_MASK				0x2cc
137 #define EMC_WDV_MASK				0x2d0
138 #define EMC_CTT_DURATION			0x2d8
139 #define EMC_CTT_TERM_CTRL			0x2dc
140 #define EMC_ZCAL_INTERVAL			0x2e0
141 #define EMC_ZCAL_WAIT_CNT			0x2e4
142 
143 #define EMC_ZQ_CAL				0x2ec
144 #define EMC_ZQ_CAL_CMD				BIT(0)
145 #define EMC_ZQ_CAL_LONG				BIT(4)
146 #define EMC_ZQ_CAL_LONG_CMD_DEV0		\
147 	(DRAM_DEV_SEL_0 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
148 #define EMC_ZQ_CAL_LONG_CMD_DEV1		\
149 	(DRAM_DEV_SEL_1 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
150 
151 #define EMC_XM2CMDPADCTRL			0x2f0
152 #define EMC_XM2DQSPADCTRL			0x2f8
153 #define EMC_XM2DQSPADCTRL2			0x2fc
154 #define EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE	BIT(0)
155 #define EMC_XM2DQSPADCTRL2_VREF_ENABLE		BIT(5)
156 #define EMC_XM2DQPADCTRL			0x300
157 #define EMC_XM2DQPADCTRL2			0x304
158 #define EMC_XM2CLKPADCTRL			0x308
159 #define EMC_XM2COMPPADCTRL			0x30c
160 #define EMC_XM2VTTGENPADCTRL			0x310
161 #define EMC_XM2VTTGENPADCTRL2			0x314
162 #define EMC_XM2VTTGENPADCTRL3			0x318
163 #define EMC_XM2DQSPADCTRL4			0x320
164 #define EMC_DLL_XFORM_DQS0			0x328
165 #define EMC_DLL_XFORM_DQS1			0x32c
166 #define EMC_DLL_XFORM_DQS2			0x330
167 #define EMC_DLL_XFORM_DQS3			0x334
168 #define EMC_DLL_XFORM_DQS4			0x338
169 #define EMC_DLL_XFORM_DQS5			0x33c
170 #define EMC_DLL_XFORM_DQS6			0x340
171 #define EMC_DLL_XFORM_DQS7			0x344
172 #define EMC_DLL_XFORM_QUSE0			0x348
173 #define EMC_DLL_XFORM_QUSE1			0x34c
174 #define EMC_DLL_XFORM_QUSE2			0x350
175 #define EMC_DLL_XFORM_QUSE3			0x354
176 #define EMC_DLL_XFORM_QUSE4			0x358
177 #define EMC_DLL_XFORM_QUSE5			0x35c
178 #define EMC_DLL_XFORM_QUSE6			0x360
179 #define EMC_DLL_XFORM_QUSE7			0x364
180 #define EMC_DLL_XFORM_DQ0			0x368
181 #define EMC_DLL_XFORM_DQ1			0x36c
182 #define EMC_DLL_XFORM_DQ2			0x370
183 #define EMC_DLL_XFORM_DQ3			0x374
184 #define EMC_DLI_TRIM_TXDQS0			0x3a8
185 #define EMC_DLI_TRIM_TXDQS1			0x3ac
186 #define EMC_DLI_TRIM_TXDQS2			0x3b0
187 #define EMC_DLI_TRIM_TXDQS3			0x3b4
188 #define EMC_DLI_TRIM_TXDQS4			0x3b8
189 #define EMC_DLI_TRIM_TXDQS5			0x3bc
190 #define EMC_DLI_TRIM_TXDQS6			0x3c0
191 #define EMC_DLI_TRIM_TXDQS7			0x3c4
192 #define EMC_STALL_THEN_EXE_AFTER_CLKCHANGE	0x3cc
193 #define EMC_SEL_DPD_CTRL			0x3d8
194 #define EMC_SEL_DPD_CTRL_DATA_SEL_DPD		BIT(8)
195 #define EMC_SEL_DPD_CTRL_ODT_SEL_DPD		BIT(5)
196 #define EMC_SEL_DPD_CTRL_RESET_SEL_DPD		BIT(4)
197 #define EMC_SEL_DPD_CTRL_CA_SEL_DPD		BIT(3)
198 #define EMC_SEL_DPD_CTRL_CLK_SEL_DPD		BIT(2)
199 #define EMC_SEL_DPD_CTRL_DDR3_MASK	\
200 	((0xf << 2) | BIT(8))
201 #define EMC_SEL_DPD_CTRL_MASK \
202 	((0x3 << 2) | BIT(5) | BIT(8))
203 #define EMC_PRE_REFRESH_REQ_CNT			0x3dc
204 #define EMC_DYN_SELF_REF_CONTROL		0x3e0
205 #define EMC_TXSRDLL				0x3e4
206 #define EMC_CCFIFO_ADDR				0x3e8
207 #define EMC_CCFIFO_DATA				0x3ec
208 #define EMC_CCFIFO_STATUS			0x3f0
209 #define EMC_CDB_CNTL_1				0x3f4
210 #define EMC_CDB_CNTL_2				0x3f8
211 #define EMC_XM2CLKPADCTRL2			0x3fc
212 #define EMC_AUTO_CAL_CONFIG2			0x458
213 #define EMC_AUTO_CAL_CONFIG3			0x45c
214 #define EMC_IBDLY				0x468
215 #define EMC_DLL_XFORM_ADDR0			0x46c
216 #define EMC_DLL_XFORM_ADDR1			0x470
217 #define EMC_DLL_XFORM_ADDR2			0x474
218 #define EMC_DSR_VTTGEN_DRV			0x47c
219 #define EMC_TXDSRVTTGEN				0x480
220 #define EMC_XM2CMDPADCTRL4			0x484
221 #define EMC_XM2CMDPADCTRL5			0x488
222 #define EMC_DLL_XFORM_DQS8			0x4a0
223 #define EMC_DLL_XFORM_DQS9			0x4a4
224 #define EMC_DLL_XFORM_DQS10			0x4a8
225 #define EMC_DLL_XFORM_DQS11			0x4ac
226 #define EMC_DLL_XFORM_DQS12			0x4b0
227 #define EMC_DLL_XFORM_DQS13			0x4b4
228 #define EMC_DLL_XFORM_DQS14			0x4b8
229 #define EMC_DLL_XFORM_DQS15			0x4bc
230 #define EMC_DLL_XFORM_QUSE8			0x4c0
231 #define EMC_DLL_XFORM_QUSE9			0x4c4
232 #define EMC_DLL_XFORM_QUSE10			0x4c8
233 #define EMC_DLL_XFORM_QUSE11			0x4cc
234 #define EMC_DLL_XFORM_QUSE12			0x4d0
235 #define EMC_DLL_XFORM_QUSE13			0x4d4
236 #define EMC_DLL_XFORM_QUSE14			0x4d8
237 #define EMC_DLL_XFORM_QUSE15			0x4dc
238 #define EMC_DLL_XFORM_DQ4			0x4e0
239 #define EMC_DLL_XFORM_DQ5			0x4e4
240 #define EMC_DLL_XFORM_DQ6			0x4e8
241 #define EMC_DLL_XFORM_DQ7			0x4ec
242 #define EMC_DLI_TRIM_TXDQS8			0x520
243 #define EMC_DLI_TRIM_TXDQS9			0x524
244 #define EMC_DLI_TRIM_TXDQS10			0x528
245 #define EMC_DLI_TRIM_TXDQS11			0x52c
246 #define EMC_DLI_TRIM_TXDQS12			0x530
247 #define EMC_DLI_TRIM_TXDQS13			0x534
248 #define EMC_DLI_TRIM_TXDQS14			0x538
249 #define EMC_DLI_TRIM_TXDQS15			0x53c
250 #define EMC_CDB_CNTL_3				0x540
251 #define EMC_XM2DQSPADCTRL5			0x544
252 #define EMC_XM2DQSPADCTRL6			0x548
253 #define EMC_XM2DQPADCTRL3			0x54c
254 #define EMC_DLL_XFORM_ADDR3			0x550
255 #define EMC_DLL_XFORM_ADDR4			0x554
256 #define EMC_DLL_XFORM_ADDR5			0x558
257 #define EMC_CFG_PIPE				0x560
258 #define EMC_QPOP				0x564
259 #define EMC_QUSE_WIDTH				0x568
260 #define EMC_PUTERM_WIDTH			0x56c
261 #define EMC_BGBIAS_CTL0				0x570
262 #define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_RX BIT(3)
263 #define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD_IBIAS_VTTGEN BIT(2)
264 #define EMC_BGBIAS_CTL0_BIAS0_DSC_E_PWRD	BIT(1)
265 #define EMC_PUTERM_ADJ				0x574
266 
267 #define DRAM_DEV_SEL_ALL			0
268 #define DRAM_DEV_SEL_0				(2 << 30)
269 #define DRAM_DEV_SEL_1				(1 << 30)
270 
271 #define EMC_CFG_POWER_FEATURES_MASK		\
272 	(EMC_CFG_DYN_SREF | EMC_CFG_DRAM_ACPD | EMC_CFG_DRAM_CLKSTOP_SR | \
273 	EMC_CFG_DRAM_CLKSTOP_PD | EMC_CFG_DSR_VTTGEN_DRV_EN)
274 #define EMC_REFCTRL_DEV_SEL(n) (((n > 1) ? 0 : 2) << EMC_REFCTRL_DEV_SEL_SHIFT)
275 #define EMC_DRAM_DEV_SEL(n) ((n > 1) ? DRAM_DEV_SEL_ALL : DRAM_DEV_SEL_0)
276 
277 /* Maximum amount of time in us. to wait for changes to become effective */
278 #define EMC_STATUS_UPDATE_TIMEOUT		1000
279 
280 enum emc_dram_type {
281 	DRAM_TYPE_DDR3 = 0,
282 	DRAM_TYPE_DDR1 = 1,
283 	DRAM_TYPE_LPDDR3 = 2,
284 	DRAM_TYPE_DDR2 = 3
285 };
286 
287 enum emc_dll_change {
288 	DLL_CHANGE_NONE,
289 	DLL_CHANGE_ON,
290 	DLL_CHANGE_OFF
291 };
292 
293 static const unsigned long emc_burst_regs[] = {
294 	EMC_RC,
295 	EMC_RFC,
296 	EMC_RFC_SLR,
297 	EMC_RAS,
298 	EMC_RP,
299 	EMC_R2W,
300 	EMC_W2R,
301 	EMC_R2P,
302 	EMC_W2P,
303 	EMC_RD_RCD,
304 	EMC_WR_RCD,
305 	EMC_RRD,
306 	EMC_REXT,
307 	EMC_WEXT,
308 	EMC_WDV,
309 	EMC_WDV_MASK,
310 	EMC_QUSE,
311 	EMC_QUSE_WIDTH,
312 	EMC_IBDLY,
313 	EMC_EINPUT,
314 	EMC_EINPUT_DURATION,
315 	EMC_PUTERM_EXTRA,
316 	EMC_PUTERM_WIDTH,
317 	EMC_PUTERM_ADJ,
318 	EMC_CDB_CNTL_1,
319 	EMC_CDB_CNTL_2,
320 	EMC_CDB_CNTL_3,
321 	EMC_QRST,
322 	EMC_QSAFE,
323 	EMC_RDV,
324 	EMC_RDV_MASK,
325 	EMC_REFRESH,
326 	EMC_BURST_REFRESH_NUM,
327 	EMC_PRE_REFRESH_REQ_CNT,
328 	EMC_PDEX2WR,
329 	EMC_PDEX2RD,
330 	EMC_PCHG2PDEN,
331 	EMC_ACT2PDEN,
332 	EMC_AR2PDEN,
333 	EMC_RW2PDEN,
334 	EMC_TXSR,
335 	EMC_TXSRDLL,
336 	EMC_TCKE,
337 	EMC_TCKESR,
338 	EMC_TPD,
339 	EMC_TFAW,
340 	EMC_TRPAB,
341 	EMC_TCLKSTABLE,
342 	EMC_TCLKSTOP,
343 	EMC_TREFBW,
344 	EMC_FBIO_CFG6,
345 	EMC_ODT_WRITE,
346 	EMC_ODT_READ,
347 	EMC_FBIO_CFG5,
348 	EMC_CFG_DIG_DLL,
349 	EMC_CFG_DIG_DLL_PERIOD,
350 	EMC_DLL_XFORM_DQS0,
351 	EMC_DLL_XFORM_DQS1,
352 	EMC_DLL_XFORM_DQS2,
353 	EMC_DLL_XFORM_DQS3,
354 	EMC_DLL_XFORM_DQS4,
355 	EMC_DLL_XFORM_DQS5,
356 	EMC_DLL_XFORM_DQS6,
357 	EMC_DLL_XFORM_DQS7,
358 	EMC_DLL_XFORM_DQS8,
359 	EMC_DLL_XFORM_DQS9,
360 	EMC_DLL_XFORM_DQS10,
361 	EMC_DLL_XFORM_DQS11,
362 	EMC_DLL_XFORM_DQS12,
363 	EMC_DLL_XFORM_DQS13,
364 	EMC_DLL_XFORM_DQS14,
365 	EMC_DLL_XFORM_DQS15,
366 	EMC_DLL_XFORM_QUSE0,
367 	EMC_DLL_XFORM_QUSE1,
368 	EMC_DLL_XFORM_QUSE2,
369 	EMC_DLL_XFORM_QUSE3,
370 	EMC_DLL_XFORM_QUSE4,
371 	EMC_DLL_XFORM_QUSE5,
372 	EMC_DLL_XFORM_QUSE6,
373 	EMC_DLL_XFORM_QUSE7,
374 	EMC_DLL_XFORM_ADDR0,
375 	EMC_DLL_XFORM_ADDR1,
376 	EMC_DLL_XFORM_ADDR2,
377 	EMC_DLL_XFORM_ADDR3,
378 	EMC_DLL_XFORM_ADDR4,
379 	EMC_DLL_XFORM_ADDR5,
380 	EMC_DLL_XFORM_QUSE8,
381 	EMC_DLL_XFORM_QUSE9,
382 	EMC_DLL_XFORM_QUSE10,
383 	EMC_DLL_XFORM_QUSE11,
384 	EMC_DLL_XFORM_QUSE12,
385 	EMC_DLL_XFORM_QUSE13,
386 	EMC_DLL_XFORM_QUSE14,
387 	EMC_DLL_XFORM_QUSE15,
388 	EMC_DLI_TRIM_TXDQS0,
389 	EMC_DLI_TRIM_TXDQS1,
390 	EMC_DLI_TRIM_TXDQS2,
391 	EMC_DLI_TRIM_TXDQS3,
392 	EMC_DLI_TRIM_TXDQS4,
393 	EMC_DLI_TRIM_TXDQS5,
394 	EMC_DLI_TRIM_TXDQS6,
395 	EMC_DLI_TRIM_TXDQS7,
396 	EMC_DLI_TRIM_TXDQS8,
397 	EMC_DLI_TRIM_TXDQS9,
398 	EMC_DLI_TRIM_TXDQS10,
399 	EMC_DLI_TRIM_TXDQS11,
400 	EMC_DLI_TRIM_TXDQS12,
401 	EMC_DLI_TRIM_TXDQS13,
402 	EMC_DLI_TRIM_TXDQS14,
403 	EMC_DLI_TRIM_TXDQS15,
404 	EMC_DLL_XFORM_DQ0,
405 	EMC_DLL_XFORM_DQ1,
406 	EMC_DLL_XFORM_DQ2,
407 	EMC_DLL_XFORM_DQ3,
408 	EMC_DLL_XFORM_DQ4,
409 	EMC_DLL_XFORM_DQ5,
410 	EMC_DLL_XFORM_DQ6,
411 	EMC_DLL_XFORM_DQ7,
412 	EMC_XM2CMDPADCTRL,
413 	EMC_XM2CMDPADCTRL4,
414 	EMC_XM2CMDPADCTRL5,
415 	EMC_XM2DQPADCTRL2,
416 	EMC_XM2DQPADCTRL3,
417 	EMC_XM2CLKPADCTRL,
418 	EMC_XM2CLKPADCTRL2,
419 	EMC_XM2COMPPADCTRL,
420 	EMC_XM2VTTGENPADCTRL,
421 	EMC_XM2VTTGENPADCTRL2,
422 	EMC_XM2VTTGENPADCTRL3,
423 	EMC_XM2DQSPADCTRL3,
424 	EMC_XM2DQSPADCTRL4,
425 	EMC_XM2DQSPADCTRL5,
426 	EMC_XM2DQSPADCTRL6,
427 	EMC_DSR_VTTGEN_DRV,
428 	EMC_TXDSRVTTGEN,
429 	EMC_FBIO_SPARE,
430 	EMC_ZCAL_WAIT_CNT,
431 	EMC_MRS_WAIT_CNT2,
432 	EMC_CTT,
433 	EMC_CTT_DURATION,
434 	EMC_CFG_PIPE,
435 	EMC_DYN_SELF_REF_CONTROL,
436 	EMC_QPOP
437 };
438 
439 struct emc_timing {
440 	unsigned long rate;
441 
442 	u32 emc_burst_data[ARRAY_SIZE(emc_burst_regs)];
443 
444 	u32 emc_auto_cal_config;
445 	u32 emc_auto_cal_config2;
446 	u32 emc_auto_cal_config3;
447 	u32 emc_auto_cal_interval;
448 	u32 emc_bgbias_ctl0;
449 	u32 emc_cfg;
450 	u32 emc_cfg_2;
451 	u32 emc_ctt_term_ctrl;
452 	u32 emc_mode_1;
453 	u32 emc_mode_2;
454 	u32 emc_mode_4;
455 	u32 emc_mode_reset;
456 	u32 emc_mrs_wait_cnt;
457 	u32 emc_sel_dpd_ctrl;
458 	u32 emc_xm2dqspadctrl2;
459 	u32 emc_zcal_cnt_long;
460 	u32 emc_zcal_interval;
461 };
462 
463 struct tegra_emc {
464 	struct device *dev;
465 
466 	struct tegra_mc *mc;
467 
468 	void __iomem *regs;
469 
470 	struct clk *clk;
471 
472 	enum emc_dram_type dram_type;
473 	unsigned int dram_num;
474 
475 	struct emc_timing last_timing;
476 	struct emc_timing *timings;
477 	unsigned int num_timings;
478 
479 	struct {
480 		struct dentry *root;
481 		unsigned long min_rate;
482 		unsigned long max_rate;
483 	} debugfs;
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 %pOFn: failed to read rate: %d\n",
892 			node, 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 %pOFn: failed to read emc burst data: %d\n",
904 			node, 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 %pOFn: failed to read " #prop ": %d\n", \
912 			node, 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 			of_node_put(child);
975 			return err;
976 		}
977 	}
978 
979 	sort(emc->timings, emc->num_timings, sizeof(*timing), cmp_timings,
980 	     NULL);
981 
982 	return 0;
983 }
984 
985 static const struct of_device_id tegra_emc_of_match[] = {
986 	{ .compatible = "nvidia,tegra124-emc" },
987 	{}
988 };
989 
990 static struct device_node *
991 tegra_emc_find_node_by_ram_code(struct device_node *node, u32 ram_code)
992 {
993 	struct device_node *np;
994 	int err;
995 
996 	for_each_child_of_node(node, np) {
997 		u32 value;
998 
999 		err = of_property_read_u32(np, "nvidia,ram-code", &value);
1000 		if (err || (value != ram_code))
1001 			continue;
1002 
1003 		return np;
1004 	}
1005 
1006 	return NULL;
1007 }
1008 
1009 /*
1010  * debugfs interface
1011  *
1012  * The memory controller driver exposes some files in debugfs that can be used
1013  * to control the EMC frequency. The top-level directory can be found here:
1014  *
1015  *   /sys/kernel/debug/emc
1016  *
1017  * It contains the following files:
1018  *
1019  *   - available_rates: This file contains a list of valid, space-separated
1020  *     EMC frequencies.
1021  *
1022  *   - min_rate: Writing a value to this file sets the given frequency as the
1023  *       floor of the permitted range. If this is higher than the currently
1024  *       configured EMC frequency, this will cause the frequency to be
1025  *       increased so that it stays within the valid range.
1026  *
1027  *   - max_rate: Similarily to the min_rate file, writing a value to this file
1028  *       sets the given frequency as the ceiling of the permitted range. If
1029  *       the value is lower than the currently configured EMC frequency, this
1030  *       will cause the frequency to be decreased so that it stays within the
1031  *       valid range.
1032  */
1033 
1034 static bool tegra_emc_validate_rate(struct tegra_emc *emc, unsigned long rate)
1035 {
1036 	unsigned int i;
1037 
1038 	for (i = 0; i < emc->num_timings; i++)
1039 		if (rate == emc->timings[i].rate)
1040 			return true;
1041 
1042 	return false;
1043 }
1044 
1045 static int tegra_emc_debug_available_rates_show(struct seq_file *s,
1046 						void *data)
1047 {
1048 	struct tegra_emc *emc = s->private;
1049 	const char *prefix = "";
1050 	unsigned int i;
1051 
1052 	for (i = 0; i < emc->num_timings; i++) {
1053 		seq_printf(s, "%s%lu", prefix, emc->timings[i].rate);
1054 		prefix = " ";
1055 	}
1056 
1057 	seq_puts(s, "\n");
1058 
1059 	return 0;
1060 }
1061 
1062 static int tegra_emc_debug_available_rates_open(struct inode *inode,
1063 						struct file *file)
1064 {
1065 	return single_open(file, tegra_emc_debug_available_rates_show,
1066 			   inode->i_private);
1067 }
1068 
1069 static const struct file_operations tegra_emc_debug_available_rates_fops = {
1070 	.open = tegra_emc_debug_available_rates_open,
1071 	.read = seq_read,
1072 	.llseek = seq_lseek,
1073 	.release = single_release,
1074 };
1075 
1076 static int tegra_emc_debug_min_rate_get(void *data, u64 *rate)
1077 {
1078 	struct tegra_emc *emc = data;
1079 
1080 	*rate = emc->debugfs.min_rate;
1081 
1082 	return 0;
1083 }
1084 
1085 static int tegra_emc_debug_min_rate_set(void *data, u64 rate)
1086 {
1087 	struct tegra_emc *emc = data;
1088 	int err;
1089 
1090 	if (!tegra_emc_validate_rate(emc, rate))
1091 		return -EINVAL;
1092 
1093 	err = clk_set_min_rate(emc->clk, rate);
1094 	if (err < 0)
1095 		return err;
1096 
1097 	emc->debugfs.min_rate = rate;
1098 
1099 	return 0;
1100 }
1101 
1102 DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_min_rate_fops,
1103 			tegra_emc_debug_min_rate_get,
1104 			tegra_emc_debug_min_rate_set, "%llu\n");
1105 
1106 static int tegra_emc_debug_max_rate_get(void *data, u64 *rate)
1107 {
1108 	struct tegra_emc *emc = data;
1109 
1110 	*rate = emc->debugfs.max_rate;
1111 
1112 	return 0;
1113 }
1114 
1115 static int tegra_emc_debug_max_rate_set(void *data, u64 rate)
1116 {
1117 	struct tegra_emc *emc = data;
1118 	int err;
1119 
1120 	if (!tegra_emc_validate_rate(emc, rate))
1121 		return -EINVAL;
1122 
1123 	err = clk_set_max_rate(emc->clk, rate);
1124 	if (err < 0)
1125 		return err;
1126 
1127 	emc->debugfs.max_rate = rate;
1128 
1129 	return 0;
1130 }
1131 
1132 DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_max_rate_fops,
1133 			tegra_emc_debug_max_rate_get,
1134 			tegra_emc_debug_max_rate_set, "%llu\n");
1135 
1136 static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc)
1137 {
1138 	unsigned int i;
1139 	int err;
1140 
1141 	emc->clk = devm_clk_get(dev, "emc");
1142 	if (IS_ERR(emc->clk)) {
1143 		if (PTR_ERR(emc->clk) != -ENODEV) {
1144 			dev_err(dev, "failed to get EMC clock: %ld\n",
1145 				PTR_ERR(emc->clk));
1146 			return;
1147 		}
1148 	}
1149 
1150 	emc->debugfs.min_rate = ULONG_MAX;
1151 	emc->debugfs.max_rate = 0;
1152 
1153 	for (i = 0; i < emc->num_timings; i++) {
1154 		if (emc->timings[i].rate < emc->debugfs.min_rate)
1155 			emc->debugfs.min_rate = emc->timings[i].rate;
1156 
1157 		if (emc->timings[i].rate > emc->debugfs.max_rate)
1158 			emc->debugfs.max_rate = emc->timings[i].rate;
1159 	}
1160 
1161 	if (!emc->num_timings) {
1162 		emc->debugfs.min_rate = clk_get_rate(emc->clk);
1163 		emc->debugfs.max_rate = emc->debugfs.min_rate;
1164 	}
1165 
1166 	err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
1167 				 emc->debugfs.max_rate);
1168 	if (err < 0) {
1169 		dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n",
1170 			emc->debugfs.min_rate, emc->debugfs.max_rate,
1171 			emc->clk);
1172 		return;
1173 	}
1174 
1175 	emc->debugfs.root = debugfs_create_dir("emc", NULL);
1176 	if (!emc->debugfs.root) {
1177 		dev_err(dev, "failed to create debugfs directory\n");
1178 		return;
1179 	}
1180 
1181 	debugfs_create_file("available_rates", S_IRUGO, emc->debugfs.root, emc,
1182 			    &tegra_emc_debug_available_rates_fops);
1183 	debugfs_create_file("min_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
1184 			    emc, &tegra_emc_debug_min_rate_fops);
1185 	debugfs_create_file("max_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
1186 			    emc, &tegra_emc_debug_max_rate_fops);
1187 }
1188 
1189 static int tegra_emc_probe(struct platform_device *pdev)
1190 {
1191 	struct platform_device *mc;
1192 	struct device_node *np;
1193 	struct tegra_emc *emc;
1194 	struct resource *res;
1195 	u32 ram_code;
1196 	int err;
1197 
1198 	emc = devm_kzalloc(&pdev->dev, sizeof(*emc), GFP_KERNEL);
1199 	if (!emc)
1200 		return -ENOMEM;
1201 
1202 	emc->dev = &pdev->dev;
1203 
1204 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1205 	emc->regs = devm_ioremap_resource(&pdev->dev, res);
1206 	if (IS_ERR(emc->regs))
1207 		return PTR_ERR(emc->regs);
1208 
1209 	np = of_parse_phandle(pdev->dev.of_node, "nvidia,memory-controller", 0);
1210 	if (!np) {
1211 		dev_err(&pdev->dev, "could not get memory controller\n");
1212 		return -ENOENT;
1213 	}
1214 
1215 	mc = of_find_device_by_node(np);
1216 	of_node_put(np);
1217 	if (!mc)
1218 		return -ENOENT;
1219 
1220 	emc->mc = platform_get_drvdata(mc);
1221 	if (!emc->mc)
1222 		return -EPROBE_DEFER;
1223 
1224 	ram_code = tegra_read_ram_code();
1225 
1226 	np = tegra_emc_find_node_by_ram_code(pdev->dev.of_node, ram_code);
1227 	if (!np) {
1228 		dev_err(&pdev->dev,
1229 			"no memory timings for RAM code %u found in DT\n",
1230 			ram_code);
1231 		return -ENOENT;
1232 	}
1233 
1234 	err = tegra_emc_load_timings_from_dt(emc, np);
1235 	of_node_put(np);
1236 	if (err)
1237 		return err;
1238 
1239 	if (emc->num_timings == 0) {
1240 		dev_err(&pdev->dev,
1241 			"no memory timings for RAM code %u registered\n",
1242 			ram_code);
1243 		return -ENOENT;
1244 	}
1245 
1246 	err = emc_init(emc);
1247 	if (err) {
1248 		dev_err(&pdev->dev, "EMC initialization failed: %d\n", err);
1249 		return err;
1250 	}
1251 
1252 	platform_set_drvdata(pdev, emc);
1253 
1254 	if (IS_ENABLED(CONFIG_DEBUG_FS))
1255 		emc_debugfs_init(&pdev->dev, emc);
1256 
1257 	return 0;
1258 };
1259 
1260 static struct platform_driver tegra_emc_driver = {
1261 	.probe = tegra_emc_probe,
1262 	.driver = {
1263 		.name = "tegra-emc",
1264 		.of_match_table = tegra_emc_of_match,
1265 		.suppress_bind_attrs = true,
1266 	},
1267 };
1268 
1269 static int tegra_emc_init(void)
1270 {
1271 	return platform_driver_register(&tegra_emc_driver);
1272 }
1273 subsys_initcall(tegra_emc_init);
1274