xref: /linux/drivers/memory/tegra/tegra114-emc.c (revision dce208b5405f40c36320bb0ee07e9df8f7f2bea4)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Tegra114 External Memory Controller driver
4  *
5  * Based on downstream driver from NVIDIA and tegra124-emc.c
6  * Copyright (C) 2011-2014 NVIDIA Corporation
7  *
8  * Copyright (C) 2024 Svyatoslav Ryhel <clamor95@gmail.com>
9  */
10 
11 #include <linux/clk.h>
12 #include <linux/clk/tegra.h>
13 #include <linux/debugfs.h>
14 #include <linux/delay.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/iopoll.h>
18 #include <linux/module.h>
19 #include <linux/mutex.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_opp.h>
23 #include <linux/sort.h>
24 #include <linux/string.h>
25 
26 #include <soc/tegra/common.h>
27 #include <soc/tegra/fuse.h>
28 #include <soc/tegra/mc.h>
29 
30 #include "mc.h"
31 #include "tegra-emc-common.h"
32 
33 #define EMC_INTSTATUS				0x0
34 #define EMC_INTSTATUS_REFRESH_OVERFLOW		BIT(3)
35 #define EMC_INTSTATUS_CLKCHANGE_COMPLETE	BIT(4)
36 
37 #define EMC_INTMASK				0x4
38 
39 #define EMC_DBG					0x8
40 #define EMC_DBG_READ_MUX_ASSEMBLY		BIT(0)
41 #define EMC_DBG_WRITE_MUX_ACTIVE		BIT(1)
42 #define EMC_DBG_FORCE_UPDATE			BIT(2)
43 #define EMC_DBG_CFG_PRIORITY			BIT(24)
44 
45 #define EMC_CFG					0xc
46 #define EMC_CFG_DSR_VTTGEN_DRV_EN		BIT(18)
47 #define EMC_CFG_PWR_MASK			((0xF << 28) | BIT(18))
48 #define EMC_CFG_DYN_SREF			BIT(28)
49 #define EMC_CFG_DRAM_ACPD			BIT(29)
50 #define EMC_CFG_DRAM_CLKSTOP_SR			BIT(30)
51 #define EMC_CFG_DRAM_CLKSTOP_PD			BIT(31)
52 
53 #define EMC_ADR_CFG				0x10
54 #define EMC_ADR_CFG_EMEM_NUMDEV			BIT(0)
55 
56 #define EMC_REFCTRL				0x20
57 #define EMC_REFCTRL_DEV_SEL_SHIFT		0
58 #define EMC_REFCTRL_ENABLE			BIT(31)
59 
60 #define EMC_TIMING_CONTROL			0x28
61 #define EMC_RC					0x2c
62 #define EMC_RFC					0x30
63 #define EMC_RAS					0x34
64 #define EMC_RP					0x38
65 #define EMC_R2W					0x3c
66 #define EMC_W2R					0x40
67 #define EMC_R2P					0x44
68 #define EMC_W2P					0x48
69 #define EMC_RD_RCD				0x4c
70 #define EMC_WR_RCD				0x50
71 #define EMC_RRD					0x54
72 #define EMC_REXT				0x58
73 #define EMC_WDV					0x5c
74 #define EMC_QUSE				0x60
75 #define EMC_QRST				0x64
76 #define EMC_QSAFE				0x68
77 #define EMC_RDV					0x6c
78 #define EMC_REFRESH				0x70
79 #define EMC_BURST_REFRESH_NUM			0x74
80 #define EMC_PDEX2WR				0x78
81 #define EMC_PDEX2RD				0x7c
82 #define EMC_PCHG2PDEN				0x80
83 #define EMC_ACT2PDEN				0x84
84 #define EMC_AR2PDEN				0x88
85 #define EMC_RW2PDEN				0x8c
86 #define EMC_TXSR				0x90
87 #define EMC_TCKE				0x94
88 #define EMC_TFAW				0x98
89 #define EMC_TRPAB				0x9c
90 #define EMC_TCLKSTABLE				0xa0
91 #define EMC_TCLKSTOP				0xa4
92 #define EMC_TREFBW				0xa8
93 #define EMC_QUSE_EXTRA				0xac
94 #define EMC_ODT_WRITE				0xb0
95 #define EMC_ODT_READ				0xb4
96 #define EMC_WEXT				0xb8
97 #define EMC_CTT					0xbc
98 #define EMC_RFC_SLR				0xc0
99 #define EMC_MRS_WAIT_CNT2			0xc4
100 
101 #define EMC_MRS_WAIT_CNT			0xc8
102 #define EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT	0
103 #define EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK	\
104 	(0x3FF << EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT)
105 #define EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT	16
106 #define EMC_MRS_WAIT_CNT_LONG_WAIT_MASK		\
107 	(0x3FF << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
108 
109 #define EMC_MRS					0xcc
110 #define EMC_MODE_SET_DLL_RESET			BIT(8)
111 #define EMC_MODE_SET_LONG_CNT			BIT(26)
112 #define EMC_EMRS				0xd0
113 #define EMC_REF					0xd4
114 #define EMC_PRE					0xd8
115 
116 #define EMC_SELF_REF				0xe0
117 #define EMC_SELF_REF_CMD_ENABLED		BIT(0)
118 #define EMC_SELF_REF_DEV_SEL_SHIFT		30
119 
120 #define EMC_MRW					0xe8
121 
122 #define EMC_MRR					0xec
123 #define EMC_MRR_MA_SHIFT			16
124 #define LPDDR2_MR4_TEMP_SHIFT			0
125 
126 #define EMC_XM2DQSPADCTRL3			0xf8
127 #define EMC_FBIO_SPARE				0x100
128 
129 #define EMC_FBIO_CFG5				0x104
130 #define EMC_FBIO_CFG5_DRAM_TYPE_MASK		0x3
131 #define EMC_FBIO_CFG5_DRAM_TYPE_SHIFT		0
132 
133 #define EMC_FBIO_CFG6				0x114
134 #define EMC_EMRS2				0x12c
135 #define EMC_MRW2				0x134
136 #define EMC_MRW4				0x13c
137 #define EMC_EINPUT				0x14c
138 #define EMC_EINPUT_DURATION			0x150
139 #define EMC_PUTERM_EXTRA			0x154
140 #define EMC_TCKESR				0x158
141 #define EMC_TPD					0x15c
142 
143 #define EMC_AUTO_CAL_CONFIG			0x2a4
144 #define EMC_AUTO_CAL_CONFIG_AUTO_CAL_START	BIT(31)
145 #define EMC_AUTO_CAL_INTERVAL			0x2a8
146 #define EMC_AUTO_CAL_STATUS			0x2ac
147 #define EMC_AUTO_CAL_STATUS_ACTIVE		BIT(31)
148 #define EMC_STATUS				0x2b4
149 #define EMC_STATUS_TIMING_UPDATE_STALLED	BIT(23)
150 
151 #define EMC_CFG_2				0x2b8
152 #define EMC_CFG_2_CLKCHANGE_REQ_ENABLE		BIT(0)
153 #define EMC_CFG_2_CLKCHANGE_PD_ENABLE		BIT(1)
154 #define EMC_CFG_2_CLKCHANGE_SR_ENABLE		BIT(2)
155 
156 #define EMC_CFG_DIG_DLL				0x2bc
157 #define EMC_CFG_DIG_DLL_PERIOD			0x2c0
158 #define EMC_RDV_MASK				0x2cc
159 #define EMC_WDV_MASK				0x2d0
160 #define EMC_CTT_DURATION			0x2d8
161 #define EMC_CTT_TERM_CTRL			0x2dc
162 #define EMC_ZCAL_INTERVAL			0x2e0
163 #define EMC_ZCAL_WAIT_CNT			0x2e4
164 
165 #define EMC_ZQ_CAL				0x2ec
166 #define EMC_ZQ_CAL_CMD				BIT(0)
167 #define EMC_ZQ_CAL_LONG				BIT(4)
168 #define EMC_ZQ_CAL_LONG_CMD_DEV0		\
169 	(DRAM_DEV_SEL_0 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
170 #define EMC_ZQ_CAL_LONG_CMD_DEV1		\
171 	(DRAM_DEV_SEL_1 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
172 
173 #define EMC_XM2CMDPADCTRL			0x2f0
174 #define EMC_XM2DQSPADCTRL			0x2f8
175 #define EMC_XM2DQSPADCTRL2			0x2fc
176 #define EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE	BIT(0)
177 #define EMC_XM2DQSPADCTRL2_VREF_ENABLE		BIT(5)
178 #define EMC_XM2DQPADCTRL			0x300
179 #define EMC_XM2DQPADCTRL2			0x304
180 #define EMC_XM2CLKPADCTRL			0x308
181 #define EMC_XM2COMPPADCTRL			0x30c
182 #define EMC_XM2VTTGENPADCTRL			0x310
183 #define EMC_XM2VTTGENPADCTRL2			0x314
184 #define EMC_XM2QUSEPADCTRL			0x318
185 #define EMC_XM2DQSPADCTRL4			0x320
186 #define EMC_DLL_XFORM_DQS0			0x328
187 #define EMC_DLL_XFORM_DQS1			0x32c
188 #define EMC_DLL_XFORM_DQS2			0x330
189 #define EMC_DLL_XFORM_DQS3			0x334
190 #define EMC_DLL_XFORM_DQS4			0x338
191 #define EMC_DLL_XFORM_DQS5			0x33c
192 #define EMC_DLL_XFORM_DQS6			0x340
193 #define EMC_DLL_XFORM_DQS7			0x344
194 #define EMC_DLL_XFORM_QUSE0			0x348
195 #define EMC_DLL_XFORM_QUSE1			0x34c
196 #define EMC_DLL_XFORM_QUSE2			0x350
197 #define EMC_DLL_XFORM_QUSE3			0x354
198 #define EMC_DLL_XFORM_QUSE4			0x358
199 #define EMC_DLL_XFORM_QUSE5			0x35c
200 #define EMC_DLL_XFORM_QUSE6			0x360
201 #define EMC_DLL_XFORM_QUSE7			0x364
202 #define EMC_DLL_XFORM_DQ0			0x368
203 #define EMC_DLL_XFORM_DQ1			0x36c
204 #define EMC_DLL_XFORM_DQ2			0x370
205 #define EMC_DLL_XFORM_DQ3			0x374
206 #define EMC_DLI_TRIM_TXDQS0			0x3a8
207 #define EMC_DLI_TRIM_TXDQS1			0x3ac
208 #define EMC_DLI_TRIM_TXDQS2			0x3b0
209 #define EMC_DLI_TRIM_TXDQS3			0x3b4
210 #define EMC_DLI_TRIM_TXDQS4			0x3b8
211 #define EMC_DLI_TRIM_TXDQS5			0x3bc
212 #define EMC_DLI_TRIM_TXDQS6			0x3c0
213 #define EMC_DLI_TRIM_TXDQS7			0x3c4
214 #define EMC_STALL_THEN_EXE_AFTER_CLKCHANGE	0x3cc
215 #define EMC_SEL_DPD_CTRL			0x3d8
216 #define EMC_SEL_DPD_CTRL_DATA_SEL_DPD		BIT(8)
217 #define EMC_SEL_DPD_CTRL_ODT_SEL_DPD		BIT(5)
218 #define EMC_SEL_DPD_CTRL_RESET_SEL_DPD		BIT(4)
219 #define EMC_SEL_DPD_CTRL_CA_SEL_DPD		BIT(3)
220 #define EMC_SEL_DPD_CTRL_CLK_SEL_DPD		BIT(2)
221 #define EMC_SEL_DPD_CTRL_DDR3_MASK	\
222 	((0xf << 2) | BIT(8))
223 #define EMC_SEL_DPD_CTRL_MASK \
224 	((0x3 << 2) | BIT(5) | BIT(8))
225 #define EMC_PRE_REFRESH_REQ_CNT			0x3dc
226 #define EMC_DYN_SELF_REF_CONTROL		0x3e0
227 #define EMC_TXSRDLL				0x3e4
228 #define EMC_CCFIFO_ADDR				0x3e8
229 #define EMC_CCFIFO_DATA				0x3ec
230 #define EMC_CCFIFO_STATUS			0x3f0
231 #define EMC_CDB_CNTL_1				0x3f4
232 #define EMC_CDB_CNTL_2				0x3f8
233 #define EMC_XM2CLKPADCTRL2			0x3fc
234 #define EMC_AUTO_CAL_CONFIG2			0x458
235 #define EMC_AUTO_CAL_CONFIG3			0x45c
236 #define EMC_IBDLY				0x468
237 #define EMC_DLL_XFORM_ADDR0			0x46c
238 #define EMC_DLL_XFORM_ADDR1			0x470
239 #define EMC_DLL_XFORM_ADDR2			0x474
240 #define EMC_DSR_VTTGEN_DRV			0x47c
241 #define EMC_TXDSRVTTGEN				0x480
242 #define EMC_XM2CMDPADCTRL4			0x484
243 
244 #define DRAM_DEV_SEL_ALL			0
245 #define DRAM_DEV_SEL_0				BIT(31)
246 #define DRAM_DEV_SEL_1				BIT(30)
247 
248 #define EMC_CFG_POWER_FEATURES_MASK		\
249 	(EMC_CFG_DYN_SREF | EMC_CFG_DRAM_ACPD | EMC_CFG_DRAM_CLKSTOP_SR | \
250 	EMC_CFG_DRAM_CLKSTOP_PD | EMC_CFG_DSR_VTTGEN_DRV_EN)
251 #define EMC_REFCTRL_DEV_SEL(n) ((((n) > 1) ? 0 : 2) << EMC_REFCTRL_DEV_SEL_SHIFT)
252 #define EMC_DRAM_DEV_SEL(n) (((n) > 1) ? DRAM_DEV_SEL_ALL : DRAM_DEV_SEL_0)
253 
254 /* Maximum amount of time in us. to wait for changes to become effective */
255 #define EMC_STATUS_UPDATE_TIMEOUT		1000
256 
257 enum emc_dram_type {
258 	DRAM_TYPE_DDR3,
259 	DRAM_TYPE_DDR1,
260 	DRAM_TYPE_LPDDR2,
261 	DRAM_TYPE_DDR2
262 };
263 
264 enum emc_dll_change {
265 	DLL_CHANGE_NONE,
266 	DLL_CHANGE_ON,
267 	DLL_CHANGE_OFF
268 };
269 
270 static const unsigned long emc_burst_regs[] = {
271 	EMC_RC,
272 	EMC_RFC,
273 	EMC_RAS,
274 	EMC_RP,
275 	EMC_R2W,
276 	EMC_W2R,
277 	EMC_R2P,
278 	EMC_W2P,
279 	EMC_RD_RCD,
280 	EMC_WR_RCD,
281 	EMC_RRD,
282 	EMC_REXT,
283 	EMC_WEXT,
284 	EMC_WDV,
285 	EMC_WDV_MASK,
286 	EMC_QUSE,
287 	EMC_IBDLY,
288 	EMC_EINPUT,
289 	EMC_EINPUT_DURATION,
290 	EMC_PUTERM_EXTRA,
291 	EMC_CDB_CNTL_1,
292 	EMC_CDB_CNTL_2,
293 	EMC_QRST,
294 	EMC_QSAFE,
295 	EMC_RDV,
296 	EMC_RDV_MASK,
297 	EMC_REFRESH,
298 	EMC_BURST_REFRESH_NUM,
299 	EMC_PRE_REFRESH_REQ_CNT,
300 	EMC_PDEX2WR,
301 	EMC_PDEX2RD,
302 	EMC_PCHG2PDEN,
303 	EMC_ACT2PDEN,
304 	EMC_AR2PDEN,
305 	EMC_RW2PDEN,
306 	EMC_TXSR,
307 	EMC_TXSRDLL,
308 	EMC_TCKE,
309 	EMC_TCKESR,
310 	EMC_TPD,
311 	EMC_TFAW,
312 	EMC_TRPAB,
313 	EMC_TCLKSTABLE,
314 	EMC_TCLKSTOP,
315 	EMC_TREFBW,
316 	EMC_QUSE_EXTRA,
317 	EMC_FBIO_CFG6,
318 	EMC_ODT_WRITE,
319 	EMC_ODT_READ,
320 	EMC_FBIO_CFG5,
321 	EMC_CFG_DIG_DLL,
322 	EMC_CFG_DIG_DLL_PERIOD,
323 	EMC_DLL_XFORM_DQS0,
324 	EMC_DLL_XFORM_DQS1,
325 	EMC_DLL_XFORM_DQS2,
326 	EMC_DLL_XFORM_DQS3,
327 	EMC_DLL_XFORM_DQS4,
328 	EMC_DLL_XFORM_DQS5,
329 	EMC_DLL_XFORM_DQS6,
330 	EMC_DLL_XFORM_DQS7,
331 	EMC_DLL_XFORM_QUSE0,
332 	EMC_DLL_XFORM_QUSE1,
333 	EMC_DLL_XFORM_QUSE2,
334 	EMC_DLL_XFORM_QUSE3,
335 	EMC_DLL_XFORM_QUSE4,
336 	EMC_DLL_XFORM_QUSE5,
337 	EMC_DLL_XFORM_QUSE6,
338 	EMC_DLL_XFORM_QUSE7,
339 	EMC_DLI_TRIM_TXDQS0,
340 	EMC_DLI_TRIM_TXDQS1,
341 	EMC_DLI_TRIM_TXDQS2,
342 	EMC_DLI_TRIM_TXDQS3,
343 	EMC_DLI_TRIM_TXDQS4,
344 	EMC_DLI_TRIM_TXDQS5,
345 	EMC_DLI_TRIM_TXDQS6,
346 	EMC_DLI_TRIM_TXDQS7,
347 	EMC_DLL_XFORM_DQ0,
348 	EMC_DLL_XFORM_DQ1,
349 	EMC_DLL_XFORM_DQ2,
350 	EMC_DLL_XFORM_DQ3,
351 	EMC_XM2CMDPADCTRL,
352 	EMC_XM2CMDPADCTRL4,
353 	EMC_XM2DQPADCTRL2,
354 	EMC_XM2CLKPADCTRL,
355 	EMC_XM2COMPPADCTRL,
356 	EMC_XM2VTTGENPADCTRL,
357 	EMC_XM2VTTGENPADCTRL2,
358 	EMC_XM2DQSPADCTRL3,
359 	EMC_XM2DQSPADCTRL4,
360 	EMC_DSR_VTTGEN_DRV,
361 	EMC_TXDSRVTTGEN,
362 	EMC_FBIO_SPARE,
363 	EMC_ZCAL_WAIT_CNT,
364 	EMC_MRS_WAIT_CNT2,
365 	EMC_CTT,
366 	EMC_CTT_DURATION,
367 	EMC_DYN_SELF_REF_CONTROL,
368 };
369 
370 struct emc_timing {
371 	unsigned long rate;
372 
373 	u32 emc_burst_data[ARRAY_SIZE(emc_burst_regs)];
374 
375 	u32 emc_auto_cal_config;
376 	u32 emc_auto_cal_config2;
377 	u32 emc_auto_cal_config3;
378 	u32 emc_auto_cal_interval;
379 	u32 emc_cfg;
380 	u32 emc_ctt_term_ctrl;
381 	u32 emc_mode_1;
382 	u32 emc_mode_2;
383 	u32 emc_mode_4;
384 	u32 emc_mode_reset;
385 	u32 emc_mrs_wait_cnt;
386 	u32 emc_sel_dpd_ctrl;
387 	u32 emc_xm2dqspadctrl2;
388 	u32 emc_zcal_cnt_long;
389 	u32 emc_zcal_interval;
390 };
391 
392 struct tegra_emc {
393 	struct device *dev;
394 	struct tegra_mc *mc;
395 	void __iomem *regs;
396 	unsigned int irq;
397 	struct clk *clk;
398 
399 	enum emc_dram_type dram_type;
400 	unsigned int dram_num;
401 
402 	struct emc_timing last_timing;
403 	struct emc_timing *timings;
404 	unsigned int num_timings;
405 
406 	struct {
407 		struct dentry *root;
408 		unsigned long min_rate;
409 		unsigned long max_rate;
410 	} debugfs;
411 
412 	struct icc_provider provider;
413 	struct tegra_emc_rate_requests reqs;
414 };
415 
416 static irqreturn_t tegra114_emc_isr(int irq, void *data)
417 {
418 	struct tegra_emc *emc = data;
419 	u32 intmask = EMC_INTSTATUS_REFRESH_OVERFLOW;
420 	u32 status;
421 
422 	status = readl_relaxed(emc->regs + EMC_INTSTATUS) & intmask;
423 	if (!status)
424 		return IRQ_NONE;
425 
426 	/* notify about HW problem */
427 	if (status & EMC_INTSTATUS_REFRESH_OVERFLOW)
428 		dev_err_ratelimited(emc->dev,
429 				    "refresh request overflow timeout\n");
430 
431 	/* clear interrupts */
432 	writel_relaxed(status, emc->regs + EMC_INTSTATUS);
433 
434 	return IRQ_HANDLED;
435 }
436 
437 /* Timing change sequence functions */
438 
439 static void emc_ccfifo_writel(struct tegra_emc *emc, u32 value,
440 			      unsigned long offset)
441 {
442 	writel(value, emc->regs + EMC_CCFIFO_DATA);
443 	writel(offset, emc->regs + EMC_CCFIFO_ADDR);
444 }
445 
446 static void emc_seq_update_timing(struct tegra_emc *emc)
447 {
448 	int ret;
449 	u32 value;
450 
451 	writel(1, emc->regs + EMC_TIMING_CONTROL);
452 
453 	ret = readl_poll_timeout_atomic(emc->regs + EMC_STATUS, value,
454 					!(value & EMC_STATUS_TIMING_UPDATE_STALLED),
455 					1, EMC_STATUS_UPDATE_TIMEOUT);
456 	if (ret)
457 		dev_err(emc->dev, "timing update timed out\n");
458 }
459 
460 static void emc_seq_disable_auto_cal(struct tegra_emc *emc)
461 {
462 	int ret;
463 	u32 value;
464 
465 	writel(0, emc->regs + EMC_AUTO_CAL_INTERVAL);
466 
467 	ret = readl_poll_timeout_atomic(emc->regs + EMC_AUTO_CAL_STATUS, value,
468 					!(value & EMC_AUTO_CAL_STATUS_ACTIVE),
469 					1, EMC_STATUS_UPDATE_TIMEOUT);
470 	if (ret)
471 		dev_err(emc->dev, "auto cal disable timed out\n");
472 }
473 
474 static void emc_seq_wait_clkchange(struct tegra_emc *emc)
475 {
476 	int ret;
477 	u32 value;
478 
479 	ret = readl_poll_timeout_atomic(emc->regs + EMC_INTSTATUS, value,
480 					value & EMC_INTSTATUS_CLKCHANGE_COMPLETE,
481 					1, EMC_STATUS_UPDATE_TIMEOUT);
482 	if (ret)
483 		dev_err(emc->dev, "clock change timed out\n");
484 }
485 
486 static struct emc_timing *tegra114_emc_find_timing(struct tegra_emc *emc,
487 						   unsigned long rate)
488 {
489 	struct emc_timing *timing = NULL;
490 	unsigned int i;
491 
492 	for (i = 0; i < emc->num_timings; i++) {
493 		if (emc->timings[i].rate == rate) {
494 			timing = &emc->timings[i];
495 			break;
496 		}
497 	}
498 
499 	if (!timing) {
500 		dev_err(emc->dev, "no timing for rate %lu\n", rate);
501 		return NULL;
502 	}
503 
504 	return timing;
505 }
506 
507 static int tegra114_emc_prepare_timing_change(struct tegra_emc *emc,
508 					      unsigned long rate)
509 {
510 	struct emc_timing *timing = tegra114_emc_find_timing(emc, rate);
511 	struct emc_timing *last = &emc->last_timing;
512 	enum emc_dll_change dll_change;
513 	unsigned int pre_wait = 0;
514 	u32 val, mask;
515 	bool next_dll_enabled = !(timing->emc_mode_1 & 0x1);
516 	bool last_dll_enabled = !(last->emc_mode_1 & 0x1);
517 	bool update = false;
518 	unsigned int i;
519 
520 	if (!timing)
521 		return -ENOENT;
522 
523 	if (next_dll_enabled == last_dll_enabled)
524 		dll_change = DLL_CHANGE_NONE;
525 	else if (next_dll_enabled)
526 		dll_change = DLL_CHANGE_ON;
527 	else
528 		dll_change = DLL_CHANGE_OFF;
529 
530 	/* Clear CLKCHANGE_COMPLETE interrupts */
531 	writel(EMC_INTSTATUS_CLKCHANGE_COMPLETE, emc->regs + EMC_INTSTATUS);
532 
533 	/* Disable dynamic self-refresh */
534 	val = readl(emc->regs + EMC_CFG);
535 	if (val & EMC_CFG_PWR_MASK) {
536 		val &= ~EMC_CFG_POWER_FEATURES_MASK;
537 		writel(val, emc->regs + EMC_CFG);
538 
539 		pre_wait = 5;
540 	}
541 
542 	/* Disable SEL_DPD_CTRL for clock change */
543 	if (emc->dram_type == DRAM_TYPE_DDR3)
544 		mask = EMC_SEL_DPD_CTRL_DDR3_MASK;
545 	else
546 		mask = EMC_SEL_DPD_CTRL_MASK;
547 
548 	val = readl(emc->regs + EMC_SEL_DPD_CTRL);
549 	if (val & mask) {
550 		val &= ~mask;
551 		writel(val, emc->regs + EMC_SEL_DPD_CTRL);
552 	}
553 
554 	/* Prepare DQ/DQS for clock change */
555 	val = readl(emc->regs + EMC_XM2DQSPADCTRL2);
556 	if (timing->emc_xm2dqspadctrl2 & EMC_XM2DQSPADCTRL2_VREF_ENABLE &&
557 	    !(val & EMC_XM2DQSPADCTRL2_VREF_ENABLE)) {
558 		val |= EMC_XM2DQSPADCTRL2_VREF_ENABLE;
559 		update = true;
560 	}
561 
562 	if (timing->emc_xm2dqspadctrl2 & EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE &&
563 	    !(val & EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE)) {
564 		val |= EMC_XM2DQSPADCTRL2_RX_FT_REC_ENABLE;
565 		update = true;
566 	}
567 
568 	if (update) {
569 		writel(val, emc->regs + EMC_XM2DQSPADCTRL2);
570 		if (pre_wait < 30)
571 			pre_wait = 30;
572 	}
573 
574 	/* Wait to settle */
575 	if (pre_wait) {
576 		emc_seq_update_timing(emc);
577 		udelay(pre_wait);
578 	}
579 
580 	/* Program CTT_TERM control */
581 	if (last->emc_ctt_term_ctrl != timing->emc_ctt_term_ctrl) {
582 		emc_seq_disable_auto_cal(emc);
583 		writel(timing->emc_ctt_term_ctrl,
584 		       emc->regs + EMC_CTT_TERM_CTRL);
585 		emc_seq_update_timing(emc);
586 	}
587 
588 	/* Program burst shadow registers */
589 	for (i = 0; i < ARRAY_SIZE(timing->emc_burst_data); ++i)
590 		writel(timing->emc_burst_data[i],
591 		       emc->regs + emc_burst_regs[i]);
592 
593 	writel(timing->emc_xm2dqspadctrl2, emc->regs + EMC_XM2DQSPADCTRL2);
594 	writel(timing->emc_zcal_interval, emc->regs + EMC_ZCAL_INTERVAL);
595 
596 	tegra_mc_write_emem_configuration(emc->mc, timing->rate);
597 
598 	val = timing->emc_cfg & ~EMC_CFG_POWER_FEATURES_MASK;
599 	emc_ccfifo_writel(emc, val, EMC_CFG);
600 
601 	/* Program AUTO_CAL_CONFIG */
602 	if (timing->emc_auto_cal_config2 != last->emc_auto_cal_config2)
603 		emc_ccfifo_writel(emc, timing->emc_auto_cal_config2,
604 				  EMC_AUTO_CAL_CONFIG2);
605 
606 	if (timing->emc_auto_cal_config3 != last->emc_auto_cal_config3)
607 		emc_ccfifo_writel(emc, timing->emc_auto_cal_config3,
608 				  EMC_AUTO_CAL_CONFIG3);
609 
610 	if (timing->emc_auto_cal_config != last->emc_auto_cal_config) {
611 		val = timing->emc_auto_cal_config;
612 		val &= EMC_AUTO_CAL_CONFIG_AUTO_CAL_START;
613 		emc_ccfifo_writel(emc, val, EMC_AUTO_CAL_CONFIG);
614 	}
615 
616 	/* DDR3: predict MRS long wait count */
617 	if (emc->dram_type == DRAM_TYPE_DDR3 &&
618 	    dll_change == DLL_CHANGE_ON) {
619 		u32 cnt = 512;
620 
621 		if (timing->emc_zcal_interval != 0 &&
622 		    last->emc_zcal_interval == 0)
623 			cnt -= emc->dram_num * 256;
624 
625 		val = (timing->emc_mrs_wait_cnt
626 			& EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK)
627 			>> EMC_MRS_WAIT_CNT_SHORT_WAIT_SHIFT;
628 		if (cnt < val)
629 			cnt = val;
630 
631 		val = timing->emc_mrs_wait_cnt
632 			& ~EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
633 		val |= (cnt << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
634 			& EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
635 
636 		writel(val, emc->regs + EMC_MRS_WAIT_CNT);
637 	}
638 
639 	/* DDR3: Turn off DLL and enter self-refresh */
640 	if (emc->dram_type == DRAM_TYPE_DDR3 && dll_change == DLL_CHANGE_OFF)
641 		emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_EMRS);
642 
643 	/* Disable refresh controller */
644 	emc_ccfifo_writel(emc, EMC_REFCTRL_DEV_SEL(emc->dram_num),
645 			  EMC_REFCTRL);
646 	if (emc->dram_type == DRAM_TYPE_DDR3)
647 		emc_ccfifo_writel(emc, EMC_DRAM_DEV_SEL(emc->dram_num) |
648 				       EMC_SELF_REF_CMD_ENABLED,
649 				  EMC_SELF_REF);
650 
651 	/* Flow control marker */
652 	emc_ccfifo_writel(emc, 1, EMC_STALL_THEN_EXE_AFTER_CLKCHANGE);
653 
654 	/* DDR3: Exit self-refresh */
655 	if (emc->dram_type == DRAM_TYPE_DDR3)
656 		emc_ccfifo_writel(emc, EMC_DRAM_DEV_SEL(emc->dram_num),
657 				  EMC_SELF_REF);
658 	emc_ccfifo_writel(emc, EMC_REFCTRL_DEV_SEL(emc->dram_num) |
659 			       EMC_REFCTRL_ENABLE,
660 			  EMC_REFCTRL);
661 
662 	/* Set DRAM mode registers */
663 	if (emc->dram_type == DRAM_TYPE_DDR3) {
664 		if (timing->emc_mode_1 != last->emc_mode_1)
665 			emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_EMRS);
666 		if (timing->emc_mode_2 != last->emc_mode_2)
667 			emc_ccfifo_writel(emc, timing->emc_mode_2, EMC_EMRS2);
668 
669 		if (timing->emc_mode_reset != last->emc_mode_reset ||
670 		    dll_change == DLL_CHANGE_ON) {
671 			val = timing->emc_mode_reset;
672 			if (dll_change == DLL_CHANGE_ON) {
673 				val |= EMC_MODE_SET_DLL_RESET;
674 				val |= EMC_MODE_SET_LONG_CNT;
675 			} else {
676 				val &= ~EMC_MODE_SET_DLL_RESET;
677 			}
678 			emc_ccfifo_writel(emc, val, EMC_MRS);
679 		}
680 	} else {
681 		if (timing->emc_mode_2 != last->emc_mode_2)
682 			emc_ccfifo_writel(emc, timing->emc_mode_2, EMC_MRW2);
683 		if (timing->emc_mode_1 != last->emc_mode_1)
684 			emc_ccfifo_writel(emc, timing->emc_mode_1, EMC_MRW);
685 		if (timing->emc_mode_4 != last->emc_mode_4)
686 			emc_ccfifo_writel(emc, timing->emc_mode_4, EMC_MRW4);
687 	}
688 
689 	/*  Issue ZCAL command if turning ZCAL on */
690 	if (timing->emc_zcal_interval != 0 && last->emc_zcal_interval == 0) {
691 		emc_ccfifo_writel(emc, EMC_ZQ_CAL_LONG_CMD_DEV0, EMC_ZQ_CAL);
692 		if (emc->dram_num > 1)
693 			emc_ccfifo_writel(emc, EMC_ZQ_CAL_LONG_CMD_DEV1,
694 					  EMC_ZQ_CAL);
695 	}
696 
697 	/*  Write to RO register to remove stall after change */
698 	emc_ccfifo_writel(emc, 0, EMC_CCFIFO_STATUS);
699 
700 	/* Disable AUTO_CAL for clock change */
701 	emc_seq_disable_auto_cal(emc);
702 
703 	/* Read register to wait until programming has settled */
704 	mc_readl(emc->mc, MC_EMEM_ADR_CFG);
705 
706 	return 0;
707 }
708 
709 static void tegra114_emc_complete_timing_change(struct tegra_emc *emc,
710 						unsigned long rate)
711 {
712 	struct emc_timing *timing = tegra114_emc_find_timing(emc, rate);
713 	struct emc_timing *last = &emc->last_timing;
714 
715 	if (!timing)
716 		return;
717 
718 	/* Wait until the state machine has settled */
719 	emc_seq_wait_clkchange(emc);
720 
721 	/* Restore AUTO_CAL */
722 	if (timing->emc_ctt_term_ctrl != last->emc_ctt_term_ctrl)
723 		writel(timing->emc_auto_cal_interval,
724 		       emc->regs + EMC_AUTO_CAL_INTERVAL);
725 
726 	/* Restore dynamic self-refresh */
727 	if (timing->emc_cfg & EMC_CFG_PWR_MASK)
728 		writel(timing->emc_cfg, emc->regs + EMC_CFG);
729 
730 	/* Set ZCAL wait count */
731 	writel(timing->emc_zcal_cnt_long, emc->regs + EMC_ZCAL_WAIT_CNT);
732 
733 	/* Wait for timing to settle */
734 	udelay(2);
735 
736 	/* Reprogram SEL_DPD_CTRL */
737 	writel(timing->emc_sel_dpd_ctrl, emc->regs + EMC_SEL_DPD_CTRL);
738 	emc_seq_update_timing(emc);
739 
740 	emc->last_timing = *timing;
741 }
742 
743 /* Initialization and deinitialization */
744 
745 static void emc_read_current_timing(struct tegra_emc *emc,
746 				    struct emc_timing *timing)
747 {
748 	unsigned int i;
749 
750 	for (i = 0; i < ARRAY_SIZE(emc_burst_regs); ++i)
751 		timing->emc_burst_data[i] =
752 			readl(emc->regs + emc_burst_regs[i]);
753 
754 	timing->emc_cfg = readl(emc->regs + EMC_CFG);
755 
756 	timing->emc_auto_cal_interval = 0;
757 	timing->emc_zcal_cnt_long = 0;
758 	timing->emc_mode_1 = 0;
759 	timing->emc_mode_2 = 0;
760 	timing->emc_mode_4 = 0;
761 	timing->emc_mode_reset = 0;
762 }
763 
764 static void emc_init(struct tegra_emc *emc)
765 {
766 	u32 emc_cfg, emc_dbg;
767 	u32 intmask = EMC_INTSTATUS_REFRESH_OVERFLOW;
768 	const char *dram_type_str;
769 
770 	emc->dram_type = readl(emc->regs + EMC_FBIO_CFG5);
771 
772 	emc->dram_type &= EMC_FBIO_CFG5_DRAM_TYPE_MASK;
773 	emc->dram_type >>= EMC_FBIO_CFG5_DRAM_TYPE_SHIFT;
774 
775 	emc->dram_num = tegra_mc_get_emem_device_count(emc->mc);
776 
777 	emc_cfg = readl_relaxed(emc->regs + EMC_CFG_2);
778 
779 	/* enable EMC and CAR to handshake on PLL divider/source changes */
780 	emc_cfg |= EMC_CFG_2_CLKCHANGE_REQ_ENABLE;
781 
782 	/* configure clock change mode accordingly to DRAM type */
783 	if (emc->dram_type == DRAM_TYPE_LPDDR2)
784 		emc_cfg |= EMC_CFG_2_CLKCHANGE_PD_ENABLE;
785 	else
786 		emc_cfg &= ~EMC_CFG_2_CLKCHANGE_PD_ENABLE;
787 
788 	writel_relaxed(emc_cfg, emc->regs + EMC_CFG_2);
789 
790 	/* initialize interrupt */
791 	writel_relaxed(intmask, emc->regs + EMC_INTMASK);
792 	writel_relaxed(0xffffffff, emc->regs + EMC_INTSTATUS);
793 
794 	/* ensure that unwanted debug features are disabled */
795 	emc_dbg = readl_relaxed(emc->regs + EMC_DBG);
796 	emc_dbg |= EMC_DBG_CFG_PRIORITY;
797 	emc_dbg &= ~EMC_DBG_READ_MUX_ASSEMBLY;
798 	emc_dbg &= ~EMC_DBG_WRITE_MUX_ACTIVE;
799 	emc_dbg &= ~EMC_DBG_FORCE_UPDATE;
800 	writel_relaxed(emc_dbg, emc->regs + EMC_DBG);
801 
802 	switch (emc->dram_type) {
803 	case DRAM_TYPE_DDR1:
804 		dram_type_str = "DDR1";
805 		break;
806 	case DRAM_TYPE_LPDDR2:
807 		dram_type_str = "LPDDR2";
808 		break;
809 	case DRAM_TYPE_DDR2:
810 		dram_type_str = "DDR2";
811 		break;
812 	case DRAM_TYPE_DDR3:
813 		dram_type_str = "DDR3";
814 		break;
815 	}
816 
817 	dev_info_once(emc->dev, "%u %s %s attached\n", emc->dram_num,
818 		      dram_type_str, emc->dram_num == 2 ? "devices" : "device");
819 
820 	emc_read_current_timing(emc, &emc->last_timing);
821 }
822 
823 static int load_one_timing_from_dt(struct tegra_emc *emc,
824 				   struct emc_timing *timing,
825 				   struct device_node *node)
826 {
827 	u32 value;
828 	int err;
829 
830 	err = of_property_read_u32(node, "clock-frequency", &value);
831 	if (err) {
832 		dev_err(emc->dev, "timing %pOFn: failed to read rate: %d\n",
833 			node, err);
834 		return err;
835 	}
836 
837 	timing->rate = value;
838 
839 	err = of_property_read_u32_array(node, "nvidia,emc-configuration",
840 					 timing->emc_burst_data,
841 					 ARRAY_SIZE(timing->emc_burst_data));
842 	if (err) {
843 		dev_err(emc->dev,
844 			"timing %pOFn: failed to read emc burst data: %d\n",
845 			node, err);
846 		return err;
847 	}
848 
849 #define EMC_READ_PROP(prop, dtprop) { \
850 	err = of_property_read_u32(node, dtprop, &timing->prop); \
851 	if (err) { \
852 		dev_err(emc->dev, "timing %pOFn: failed to read " #prop ": %d\n", \
853 			node, err); \
854 		return err; \
855 	} \
856 }
857 
858 	EMC_READ_PROP(emc_auto_cal_config, "nvidia,emc-auto-cal-config")
859 	EMC_READ_PROP(emc_auto_cal_config2, "nvidia,emc-auto-cal-config2")
860 	EMC_READ_PROP(emc_auto_cal_config3, "nvidia,emc-auto-cal-config3")
861 	EMC_READ_PROP(emc_auto_cal_interval, "nvidia,emc-auto-cal-interval")
862 	EMC_READ_PROP(emc_cfg, "nvidia,emc-cfg")
863 	EMC_READ_PROP(emc_ctt_term_ctrl, "nvidia,emc-ctt-term-ctrl")
864 	EMC_READ_PROP(emc_mode_1, "nvidia,emc-mode-1")
865 	EMC_READ_PROP(emc_mode_2, "nvidia,emc-mode-2")
866 	EMC_READ_PROP(emc_mode_4, "nvidia,emc-mode-4")
867 	EMC_READ_PROP(emc_mode_reset, "nvidia,emc-mode-reset")
868 	EMC_READ_PROP(emc_mrs_wait_cnt, "nvidia,emc-mrs-wait-cnt")
869 	EMC_READ_PROP(emc_sel_dpd_ctrl, "nvidia,emc-sel-dpd-ctrl")
870 	EMC_READ_PROP(emc_xm2dqspadctrl2, "nvidia,emc-xm2dqspadctrl2")
871 	EMC_READ_PROP(emc_zcal_cnt_long, "nvidia,emc-zcal-cnt-long")
872 	EMC_READ_PROP(emc_zcal_interval, "nvidia,emc-zcal-interval")
873 
874 #undef EMC_READ_PROP
875 
876 	return 0;
877 }
878 
879 static int cmp_timings(const void *_a, const void *_b)
880 {
881 	const struct emc_timing *a = _a;
882 	const struct emc_timing *b = _b;
883 
884 	if (a->rate < b->rate)
885 		return -1;
886 	else if (a->rate == b->rate)
887 		return 0;
888 	else
889 		return 1;
890 }
891 
892 static int emc_check_mc_timings(struct tegra_emc *emc)
893 {
894 	struct tegra_mc *mc = emc->mc;
895 	unsigned int i;
896 
897 	if (emc->num_timings != mc->num_timings) {
898 		dev_err(emc->dev, "emc/mc timings number mismatch: %u %u\n",
899 			emc->num_timings, mc->num_timings);
900 		return -EINVAL;
901 	}
902 
903 	for (i = 0; i < mc->num_timings; i++) {
904 		if (emc->timings[i].rate != mc->timings[i].rate) {
905 			dev_err(emc->dev,
906 				"emc/mc timing rate mismatch: %lu %lu\n",
907 				emc->timings[i].rate, mc->timings[i].rate);
908 			return -EINVAL;
909 		}
910 	}
911 
912 	return 0;
913 }
914 
915 static int tegra114_emc_load_timings_from_dt(struct tegra_emc *emc,
916 					     struct device_node *node)
917 {
918 	int child_count = of_get_child_count(node);
919 	struct emc_timing *timing;
920 	unsigned int i = 0;
921 	int err;
922 
923 	emc->timings = devm_kcalloc(emc->dev, child_count, sizeof(*timing),
924 				    GFP_KERNEL);
925 	if (!emc->timings)
926 		return -ENOMEM;
927 
928 	emc->num_timings = child_count;
929 
930 	for_each_child_of_node_scoped(node, child) {
931 		timing = &emc->timings[i++];
932 
933 		err = load_one_timing_from_dt(emc, timing, child);
934 		if (err)
935 			return err;
936 	}
937 
938 	sort(emc->timings, emc->num_timings, sizeof(*timing), cmp_timings,
939 	     NULL);
940 
941 	err = emc_check_mc_timings(emc);
942 	if (err)
943 		return err;
944 
945 	dev_info_once(emc->dev,
946 		      "got %u timings for RAM code %u (min %luMHz max %luMHz)\n",
947 		      emc->num_timings,
948 		      tegra_read_ram_code(),
949 		      emc->timings[0].rate / 1000000,
950 		      emc->timings[emc->num_timings - 1].rate / 1000000);
951 
952 	return 0;
953 }
954 
955 static struct device_node *
956 tegra114_emc_find_node_by_ram_code(struct device_node *node, u32 ram_code)
957 {
958 	struct device_node *np;
959 	int err;
960 
961 	for_each_child_of_node(node, np) {
962 		u32 value;
963 
964 		err = of_property_read_u32(np, "nvidia,ram-code", &value);
965 		if (err || value != ram_code)
966 			continue;
967 
968 		return np;
969 	}
970 
971 	return NULL;
972 }
973 
974 /*
975  * debugfs interface
976  *
977  * The memory controller driver exposes some files in debugfs that can be used
978  * to control the EMC frequency. The top-level directory can be found here:
979  *
980  *   /sys/kernel/debug/emc
981  *
982  * It contains the following files:
983  *
984  *   - available_rates: This file contains a list of valid, space-separated
985  *     EMC frequencies.
986  *
987  *   - min_rate: Writing a value to this file sets the given frequency as the
988  *       floor of the permitted range. If this is higher than the currently
989  *       configured EMC frequency, this will cause the frequency to be
990  *       increased so that it stays within the valid range.
991  *
992  *   - max_rate: Similarly to the min_rate file, writing a value to this file
993  *       sets the given frequency as the ceiling of the permitted range. If
994  *       the value is lower than the currently configured EMC frequency, this
995  *       will cause the frequency to be decreased so that it stays within the
996  *       valid range.
997  */
998 
999 static bool tegra114_emc_validate_rate(struct tegra_emc *emc, unsigned long rate)
1000 {
1001 	unsigned int i;
1002 
1003 	for (i = 0; i < emc->num_timings; i++)
1004 		if (rate == emc->timings[i].rate)
1005 			return true;
1006 
1007 	return false;
1008 }
1009 
1010 static int tegra114_emc_debug_available_rates_show(struct seq_file *s,
1011 						   void *data)
1012 {
1013 	struct tegra_emc *emc = s->private;
1014 	const char *prefix = "";
1015 	unsigned int i;
1016 
1017 	for (i = 0; i < emc->num_timings; i++) {
1018 		seq_printf(s, "%s%lu", prefix, emc->timings[i].rate);
1019 		prefix = " ";
1020 	}
1021 
1022 	seq_puts(s, "\n");
1023 
1024 	return 0;
1025 }
1026 
1027 DEFINE_SHOW_ATTRIBUTE(tegra114_emc_debug_available_rates);
1028 
1029 static int tegra114_emc_debug_min_rate_get(void *data, u64 *rate)
1030 {
1031 	struct tegra_emc *emc = data;
1032 
1033 	*rate = emc->debugfs.min_rate;
1034 
1035 	return 0;
1036 }
1037 
1038 static int tegra114_emc_debug_min_rate_set(void *data, u64 rate)
1039 {
1040 	struct tegra_emc *emc = data;
1041 	int err;
1042 
1043 	if (!tegra114_emc_validate_rate(emc, rate))
1044 		return -EINVAL;
1045 
1046 	err = tegra_emc_set_min_rate(&emc->reqs, rate, TEGRA_EMC_RATE_DEBUG);
1047 	if (err < 0)
1048 		return err;
1049 
1050 	emc->debugfs.min_rate = rate;
1051 
1052 	return 0;
1053 }
1054 
1055 DEFINE_DEBUGFS_ATTRIBUTE(tegra114_emc_debug_min_rate_fops,
1056 			 tegra114_emc_debug_min_rate_get,
1057 			 tegra114_emc_debug_min_rate_set, "%llu\n");
1058 
1059 static int tegra114_emc_debug_max_rate_get(void *data, u64 *rate)
1060 {
1061 	struct tegra_emc *emc = data;
1062 
1063 	*rate = emc->debugfs.max_rate;
1064 
1065 	return 0;
1066 }
1067 
1068 static int tegra114_emc_debug_max_rate_set(void *data, u64 rate)
1069 {
1070 	struct tegra_emc *emc = data;
1071 	int err;
1072 
1073 	if (!tegra114_emc_validate_rate(emc, rate))
1074 		return -EINVAL;
1075 
1076 	err = tegra_emc_set_max_rate(&emc->reqs, rate, TEGRA_EMC_RATE_DEBUG);
1077 	if (err < 0)
1078 		return err;
1079 
1080 	emc->debugfs.max_rate = rate;
1081 
1082 	return 0;
1083 }
1084 
1085 DEFINE_DEBUGFS_ATTRIBUTE(tegra114_emc_debug_max_rate_fops,
1086 			 tegra114_emc_debug_max_rate_get,
1087 			 tegra114_emc_debug_max_rate_set, "%llu\n");
1088 
1089 static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc)
1090 {
1091 	unsigned int i;
1092 	int err;
1093 
1094 	emc->debugfs.min_rate = ULONG_MAX;
1095 	emc->debugfs.max_rate = 0;
1096 
1097 	for (i = 0; i < emc->num_timings; i++) {
1098 		if (emc->timings[i].rate < emc->debugfs.min_rate)
1099 			emc->debugfs.min_rate = emc->timings[i].rate;
1100 
1101 		if (emc->timings[i].rate > emc->debugfs.max_rate)
1102 			emc->debugfs.max_rate = emc->timings[i].rate;
1103 	}
1104 
1105 	if (!emc->num_timings) {
1106 		emc->debugfs.min_rate = clk_get_rate(emc->clk);
1107 		emc->debugfs.max_rate = emc->debugfs.min_rate;
1108 	}
1109 
1110 	err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
1111 				 emc->debugfs.max_rate);
1112 	if (err < 0) {
1113 		dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n",
1114 			emc->debugfs.min_rate, emc->debugfs.max_rate,
1115 			emc->clk);
1116 		return;
1117 	}
1118 
1119 	emc->debugfs.root = debugfs_create_dir("emc", NULL);
1120 
1121 	debugfs_create_file("available_rates", 0444, emc->debugfs.root, emc,
1122 			    &tegra114_emc_debug_available_rates_fops);
1123 	debugfs_create_file("min_rate", 0644, emc->debugfs.root,
1124 			    emc, &tegra114_emc_debug_min_rate_fops);
1125 	debugfs_create_file("max_rate", 0644, emc->debugfs.root,
1126 			    emc, &tegra114_emc_debug_max_rate_fops);
1127 }
1128 
1129 static inline struct tegra_emc *
1130 to_tegra_emc_provider(struct icc_provider *provider)
1131 {
1132 	return container_of(provider, struct tegra_emc, provider);
1133 }
1134 
1135 static struct icc_node_data *
1136 emc_of_icc_xlate_extended(const struct of_phandle_args *spec, void *data)
1137 {
1138 	struct icc_provider *provider = data;
1139 	struct icc_node_data *ndata;
1140 	struct icc_node *node;
1141 
1142 	/* External Memory is the only possible ICC route */
1143 	list_for_each_entry(node, &provider->nodes, node_list) {
1144 		if (node->id != TEGRA_ICC_EMEM)
1145 			continue;
1146 
1147 		ndata = kzalloc_obj(*ndata);
1148 		if (!ndata)
1149 			return ERR_PTR(-ENOMEM);
1150 
1151 		/*
1152 		 * SRC and DST nodes should have matching TAG in order to have
1153 		 * it set by default for a requested path.
1154 		 */
1155 		ndata->tag = TEGRA_MC_ICC_TAG_ISO;
1156 		ndata->node = node;
1157 
1158 		return ndata;
1159 	}
1160 
1161 	return ERR_PTR(-EPROBE_DEFER);
1162 }
1163 
1164 static int emc_icc_set(struct icc_node *src, struct icc_node *dst)
1165 {
1166 	struct tegra_emc *emc = to_tegra_emc_provider(dst->provider);
1167 	unsigned long long peak_bw = icc_units_to_bps(dst->peak_bw);
1168 	unsigned long long avg_bw = icc_units_to_bps(dst->avg_bw);
1169 	unsigned long long rate = max(avg_bw, peak_bw);
1170 	unsigned int dram_data_bus_width_bytes = 4;
1171 	const unsigned int ddr = 2;
1172 	int err;
1173 
1174 	/*
1175 	 * Tegra114 EMC runs on a clock rate of SDRAM bus. This means that
1176 	 * EMC clock rate is twice smaller than the peak data rate because
1177 	 * data is sampled on both EMC clock edges.
1178 	 */
1179 	do_div(rate, ddr * dram_data_bus_width_bytes);
1180 	rate = min_t(u64, rate, U32_MAX);
1181 
1182 	err = tegra_emc_set_min_rate(&emc->reqs, rate, TEGRA_EMC_RATE_ICC);
1183 	if (err)
1184 		return err;
1185 
1186 	return 0;
1187 }
1188 
1189 static int tegra114_emc_interconnect_init(struct tegra_emc *emc)
1190 {
1191 	const struct tegra_mc_soc *soc = emc->mc->soc;
1192 	struct icc_node *node;
1193 	int err;
1194 
1195 	emc->provider.dev = emc->dev;
1196 	emc->provider.set = emc_icc_set;
1197 	emc->provider.data = &emc->provider;
1198 	emc->provider.aggregate = soc->icc_ops->aggregate;
1199 	emc->provider.xlate_extended = emc_of_icc_xlate_extended;
1200 
1201 	icc_provider_init(&emc->provider);
1202 
1203 	/* create External Memory Controller node */
1204 	node = icc_node_create(TEGRA_ICC_EMC);
1205 	if (IS_ERR(node)) {
1206 		err = PTR_ERR(node);
1207 		goto err_msg;
1208 	}
1209 
1210 	node->name = "External Memory Controller";
1211 	icc_node_add(node, &emc->provider);
1212 
1213 	/* link External Memory Controller to External Memory (DRAM) */
1214 	err = icc_link_create(node, TEGRA_ICC_EMEM);
1215 	if (err)
1216 		goto remove_nodes;
1217 
1218 	/* create External Memory node */
1219 	node = icc_node_create(TEGRA_ICC_EMEM);
1220 	if (IS_ERR(node)) {
1221 		err = PTR_ERR(node);
1222 		goto remove_nodes;
1223 	}
1224 
1225 	node->name = "External Memory (DRAM)";
1226 	icc_node_add(node, &emc->provider);
1227 
1228 	err = icc_provider_register(&emc->provider);
1229 	if (err)
1230 		goto remove_nodes;
1231 
1232 	return 0;
1233 
1234 remove_nodes:
1235 	icc_nodes_remove(&emc->provider);
1236 err_msg:
1237 	dev_err(emc->dev, "failed to initialize ICC: %d\n", err);
1238 
1239 	return err;
1240 }
1241 
1242 static void devm_tegra114_emc_unset_callback(void *data)
1243 {
1244 	tegra124_clk_set_emc_callbacks(NULL, NULL);
1245 }
1246 
1247 static int tegra114_emc_probe(struct platform_device *pdev)
1248 {
1249 	struct tegra_core_opp_params opp_params = {};
1250 	struct device *dev = &pdev->dev;
1251 	struct device_node *np;
1252 	struct tegra_emc *emc;
1253 	u32 ram_code;
1254 	int err;
1255 
1256 	emc = devm_kzalloc(dev, sizeof(*emc), GFP_KERNEL);
1257 	if (!emc)
1258 		return -ENOMEM;
1259 
1260 	emc->dev = dev;
1261 
1262 	emc->regs = devm_platform_ioremap_resource(pdev, 0);
1263 	if (IS_ERR(emc->regs))
1264 		return PTR_ERR(emc->regs);
1265 
1266 	emc->mc = devm_tegra_memory_controller_get(dev);
1267 	if (IS_ERR(emc->mc))
1268 		return PTR_ERR(emc->mc);
1269 
1270 	ram_code = tegra_read_ram_code();
1271 
1272 	np = tegra114_emc_find_node_by_ram_code(dev->of_node, ram_code);
1273 	if (np) {
1274 		err = tegra114_emc_load_timings_from_dt(emc, np);
1275 		of_node_put(np);
1276 		if (err)
1277 			return err;
1278 	} else {
1279 		dev_info_once(dev, "no memory timings for RAM code %u found in DT\n",
1280 			      ram_code);
1281 	}
1282 
1283 	emc_init(emc);
1284 
1285 	platform_set_drvdata(pdev, emc);
1286 
1287 	tegra124_clk_set_emc_callbacks(tegra114_emc_prepare_timing_change,
1288 				       tegra114_emc_complete_timing_change);
1289 
1290 	err = devm_add_action_or_reset(dev, devm_tegra114_emc_unset_callback,
1291 				       NULL);
1292 	if (err)
1293 		return err;
1294 
1295 	err = platform_get_irq(pdev, 0);
1296 	if (err < 0)
1297 		return err;
1298 
1299 	emc->irq = err;
1300 
1301 	err = devm_request_irq(dev, emc->irq, tegra114_emc_isr, 0,
1302 			       dev_name(dev), emc);
1303 	if (err)
1304 		return dev_err_probe(dev, err, "failed to request irq\n");
1305 
1306 	emc->clk = devm_clk_get(dev, "emc");
1307 	if (IS_ERR(emc->clk))
1308 		return dev_err_probe(dev, PTR_ERR(emc->clk),
1309 				     "failed to get EMC clock\n");
1310 
1311 	opp_params.init_state = true;
1312 
1313 	err = devm_tegra_core_dev_init_opp_table(dev, &opp_params);
1314 	if (err)
1315 		return err;
1316 
1317 	tegra_emc_rate_requests_init(&emc->reqs, dev);
1318 
1319 	if (IS_ENABLED(CONFIG_DEBUG_FS))
1320 		emc_debugfs_init(dev, emc);
1321 
1322 	tegra114_emc_interconnect_init(emc);
1323 
1324 	/*
1325 	 * Don't allow the kernel module to be unloaded. Unloading adds some
1326 	 * extra complexity which doesn't really worth the effort in a case of
1327 	 * this driver.
1328 	 */
1329 	try_module_get(THIS_MODULE);
1330 
1331 	return 0;
1332 };
1333 
1334 static const struct of_device_id tegra114_emc_of_match[] = {
1335 	{ .compatible = "nvidia,tegra114-emc" },
1336 	{ }
1337 };
1338 MODULE_DEVICE_TABLE(of, tegra114_emc_of_match);
1339 
1340 static struct platform_driver tegra114_emc_driver = {
1341 	.probe = tegra114_emc_probe,
1342 	.driver = {
1343 		.name = "tegra114-emc",
1344 		.of_match_table = tegra114_emc_of_match,
1345 		.suppress_bind_attrs = true,
1346 		.sync_state = icc_sync_state,
1347 	},
1348 };
1349 module_platform_driver(tegra114_emc_driver);
1350 
1351 MODULE_AUTHOR("Svyatoslav Ryhel <clamor95@gmail.com>");
1352 MODULE_DESCRIPTION("NVIDIA Tegra114 EMC driver");
1353 MODULE_LICENSE("GPL");
1354