xref: /openbmc/linux/drivers/memory/emif.c (revision f3539c12)
1 /*
2  * EMIF driver
3  *
4  * Copyright (C) 2012 Texas Instruments, Inc.
5  *
6  * Aneesh V <aneesh@ti.com>
7  * Santosh Shilimkar <santosh.shilimkar@ti.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/err.h>
14 #include <linux/kernel.h>
15 #include <linux/reboot.h>
16 #include <linux/platform_data/emif_plat.h>
17 #include <linux/io.h>
18 #include <linux/device.h>
19 #include <linux/platform_device.h>
20 #include <linux/interrupt.h>
21 #include <linux/slab.h>
22 #include <linux/of.h>
23 #include <linux/debugfs.h>
24 #include <linux/seq_file.h>
25 #include <linux/module.h>
26 #include <linux/list.h>
27 #include <linux/spinlock.h>
28 #include <linux/pm.h>
29 #include <memory/jedec_ddr.h>
30 #include "emif.h"
31 #include "of_memory.h"
32 
33 /**
34  * struct emif_data - Per device static data for driver's use
35  * @duplicate:			Whether the DDR devices attached to this EMIF
36  *				instance are exactly same as that on EMIF1. In
37  *				this case we can save some memory and processing
38  * @temperature_level:		Maximum temperature of LPDDR2 devices attached
39  *				to this EMIF - read from MR4 register. If there
40  *				are two devices attached to this EMIF, this
41  *				value is the maximum of the two temperature
42  *				levels.
43  * @node:			node in the device list
44  * @base:			base address of memory-mapped IO registers.
45  * @dev:			device pointer.
46  * @addressing			table with addressing information from the spec
47  * @regs_cache:			An array of 'struct emif_regs' that stores
48  *				calculated register values for different
49  *				frequencies, to avoid re-calculating them on
50  *				each DVFS transition.
51  * @curr_regs:			The set of register values used in the last
52  *				frequency change (i.e. corresponding to the
53  *				frequency in effect at the moment)
54  * @plat_data:			Pointer to saved platform data.
55  * @debugfs_root:		dentry to the root folder for EMIF in debugfs
56  * @np_ddr:			Pointer to ddr device tree node
57  */
58 struct emif_data {
59 	u8				duplicate;
60 	u8				temperature_level;
61 	u8				lpmode;
62 	struct list_head		node;
63 	unsigned long			irq_state;
64 	void __iomem			*base;
65 	struct device			*dev;
66 	const struct lpddr2_addressing	*addressing;
67 	struct emif_regs		*regs_cache[EMIF_MAX_NUM_FREQUENCIES];
68 	struct emif_regs		*curr_regs;
69 	struct emif_platform_data	*plat_data;
70 	struct dentry			*debugfs_root;
71 	struct device_node		*np_ddr;
72 };
73 
74 static struct emif_data *emif1;
75 static spinlock_t	emif_lock;
76 static unsigned long	irq_state;
77 static u32		t_ck; /* DDR clock period in ps */
78 static LIST_HEAD(device_list);
79 
80 #ifdef CONFIG_DEBUG_FS
81 static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
82 	struct emif_regs *regs)
83 {
84 	u32 type = emif->plat_data->device_info->type;
85 	u32 ip_rev = emif->plat_data->ip_rev;
86 
87 	seq_printf(s, "EMIF register cache dump for %dMHz\n",
88 		regs->freq/1000000);
89 
90 	seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
91 	seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
92 	seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
93 	seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
94 
95 	if (ip_rev == EMIF_4D) {
96 		seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
97 			regs->read_idle_ctrl_shdw_normal);
98 		seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
99 			regs->read_idle_ctrl_shdw_volt_ramp);
100 	} else if (ip_rev == EMIF_4D5) {
101 		seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
102 			regs->dll_calib_ctrl_shdw_normal);
103 		seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
104 			regs->dll_calib_ctrl_shdw_volt_ramp);
105 	}
106 
107 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
108 		seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
109 			regs->ref_ctrl_shdw_derated);
110 		seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
111 			regs->sdram_tim1_shdw_derated);
112 		seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
113 			regs->sdram_tim3_shdw_derated);
114 	}
115 }
116 
117 static int emif_regdump_show(struct seq_file *s, void *unused)
118 {
119 	struct emif_data	*emif	= s->private;
120 	struct emif_regs	**regs_cache;
121 	int			i;
122 
123 	if (emif->duplicate)
124 		regs_cache = emif1->regs_cache;
125 	else
126 		regs_cache = emif->regs_cache;
127 
128 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
129 		do_emif_regdump_show(s, emif, regs_cache[i]);
130 		seq_printf(s, "\n");
131 	}
132 
133 	return 0;
134 }
135 
136 static int emif_regdump_open(struct inode *inode, struct file *file)
137 {
138 	return single_open(file, emif_regdump_show, inode->i_private);
139 }
140 
141 static const struct file_operations emif_regdump_fops = {
142 	.open			= emif_regdump_open,
143 	.read			= seq_read,
144 	.release		= single_release,
145 };
146 
147 static int emif_mr4_show(struct seq_file *s, void *unused)
148 {
149 	struct emif_data *emif = s->private;
150 
151 	seq_printf(s, "MR4=%d\n", emif->temperature_level);
152 	return 0;
153 }
154 
155 static int emif_mr4_open(struct inode *inode, struct file *file)
156 {
157 	return single_open(file, emif_mr4_show, inode->i_private);
158 }
159 
160 static const struct file_operations emif_mr4_fops = {
161 	.open			= emif_mr4_open,
162 	.read			= seq_read,
163 	.release		= single_release,
164 };
165 
166 static int __init_or_module emif_debugfs_init(struct emif_data *emif)
167 {
168 	struct dentry	*dentry;
169 	int		ret;
170 
171 	dentry = debugfs_create_dir(dev_name(emif->dev), NULL);
172 	if (!dentry) {
173 		ret = -ENOMEM;
174 		goto err0;
175 	}
176 	emif->debugfs_root = dentry;
177 
178 	dentry = debugfs_create_file("regcache_dump", S_IRUGO,
179 			emif->debugfs_root, emif, &emif_regdump_fops);
180 	if (!dentry) {
181 		ret = -ENOMEM;
182 		goto err1;
183 	}
184 
185 	dentry = debugfs_create_file("mr4", S_IRUGO,
186 			emif->debugfs_root, emif, &emif_mr4_fops);
187 	if (!dentry) {
188 		ret = -ENOMEM;
189 		goto err1;
190 	}
191 
192 	return 0;
193 err1:
194 	debugfs_remove_recursive(emif->debugfs_root);
195 err0:
196 	return ret;
197 }
198 
199 static void __exit emif_debugfs_exit(struct emif_data *emif)
200 {
201 	debugfs_remove_recursive(emif->debugfs_root);
202 	emif->debugfs_root = NULL;
203 }
204 #else
205 static inline int __init_or_module emif_debugfs_init(struct emif_data *emif)
206 {
207 	return 0;
208 }
209 
210 static inline void __exit emif_debugfs_exit(struct emif_data *emif)
211 {
212 }
213 #endif
214 
215 /*
216  * Calculate the period of DDR clock from frequency value
217  */
218 static void set_ddr_clk_period(u32 freq)
219 {
220 	/* Divide 10^12 by frequency to get period in ps */
221 	t_ck = (u32)DIV_ROUND_UP_ULL(1000000000000ull, freq);
222 }
223 
224 /*
225  * Get bus width used by EMIF. Note that this may be different from the
226  * bus width of the DDR devices used. For instance two 16-bit DDR devices
227  * may be connected to a given CS of EMIF. In this case bus width as far
228  * as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
229  */
230 static u32 get_emif_bus_width(struct emif_data *emif)
231 {
232 	u32		width;
233 	void __iomem	*base = emif->base;
234 
235 	width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
236 			>> NARROW_MODE_SHIFT;
237 	width = width == 0 ? 32 : 16;
238 
239 	return width;
240 }
241 
242 /*
243  * Get the CL from SDRAM_CONFIG register
244  */
245 static u32 get_cl(struct emif_data *emif)
246 {
247 	u32		cl;
248 	void __iomem	*base = emif->base;
249 
250 	cl = (readl(base + EMIF_SDRAM_CONFIG) & CL_MASK) >> CL_SHIFT;
251 
252 	return cl;
253 }
254 
255 static void set_lpmode(struct emif_data *emif, u8 lpmode)
256 {
257 	u32 temp;
258 	void __iomem *base = emif->base;
259 
260 	/*
261 	 * Workaround for errata i743 - LPDDR2 Power-Down State is Not
262 	 * Efficient
263 	 *
264 	 * i743 DESCRIPTION:
265 	 * The EMIF supports power-down state for low power. The EMIF
266 	 * automatically puts the SDRAM into power-down after the memory is
267 	 * not accessed for a defined number of cycles and the
268 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set to 0x4.
269 	 * As the EMIF supports automatic output impedance calibration, a ZQ
270 	 * calibration long command is issued every time it exits active
271 	 * power-down and precharge power-down modes. The EMIF waits and
272 	 * blocks any other command during this calibration.
273 	 * The EMIF does not allow selective disabling of ZQ calibration upon
274 	 * exit of power-down mode. Due to very short periods of power-down
275 	 * cycles, ZQ calibration overhead creates bandwidth issues and
276 	 * increases overall system power consumption. On the other hand,
277 	 * issuing ZQ calibration long commands when exiting self-refresh is
278 	 * still required.
279 	 *
280 	 * WORKAROUND
281 	 * Because there is no power consumption benefit of the power-down due
282 	 * to the calibration and there is a performance risk, the guideline
283 	 * is to not allow power-down state and, therefore, to not have set
284 	 * the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field to 0x4.
285 	 */
286 	if ((emif->plat_data->ip_rev == EMIF_4D) &&
287 	    (EMIF_LP_MODE_PWR_DN == lpmode)) {
288 		WARN_ONCE(1,
289 			  "REG_LP_MODE = LP_MODE_PWR_DN(4) is prohibited by"
290 			  "erratum i743 switch to LP_MODE_SELF_REFRESH(2)\n");
291 		/* rollback LP_MODE to Self-refresh mode */
292 		lpmode = EMIF_LP_MODE_SELF_REFRESH;
293 	}
294 
295 	temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
296 	temp &= ~LP_MODE_MASK;
297 	temp |= (lpmode << LP_MODE_SHIFT);
298 	writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
299 }
300 
301 static void do_freq_update(void)
302 {
303 	struct emif_data *emif;
304 
305 	/*
306 	 * Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
307 	 *
308 	 * i728 DESCRIPTION:
309 	 * The EMIF automatically puts the SDRAM into self-refresh mode
310 	 * after the EMIF has not performed accesses during
311 	 * EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
312 	 * and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
313 	 * to 0x2. If during a small window the following three events
314 	 * occur:
315 	 * - The SR_TIMING counter expires
316 	 * - And frequency change is requested
317 	 * - And OCP access is requested
318 	 * Then it causes instable clock on the DDR interface.
319 	 *
320 	 * WORKAROUND
321 	 * To avoid the occurrence of the three events, the workaround
322 	 * is to disable the self-refresh when requesting a frequency
323 	 * change. Before requesting a frequency change the software must
324 	 * program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
325 	 * frequency change has been done, the software can reprogram
326 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
327 	 */
328 	list_for_each_entry(emif, &device_list, node) {
329 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
330 			set_lpmode(emif, EMIF_LP_MODE_DISABLE);
331 	}
332 
333 	/*
334 	 * TODO: Do FREQ_UPDATE here when an API
335 	 * is available for this as part of the new
336 	 * clock framework
337 	 */
338 
339 	list_for_each_entry(emif, &device_list, node) {
340 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
341 			set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
342 	}
343 }
344 
345 /* Find addressing table entry based on the device's type and density */
346 static const struct lpddr2_addressing *get_addressing_table(
347 	const struct ddr_device_info *device_info)
348 {
349 	u32		index, type, density;
350 
351 	type = device_info->type;
352 	density = device_info->density;
353 
354 	switch (type) {
355 	case DDR_TYPE_LPDDR2_S4:
356 		index = density - 1;
357 		break;
358 	case DDR_TYPE_LPDDR2_S2:
359 		switch (density) {
360 		case DDR_DENSITY_1Gb:
361 		case DDR_DENSITY_2Gb:
362 			index = density + 3;
363 			break;
364 		default:
365 			index = density - 1;
366 		}
367 		break;
368 	default:
369 		return NULL;
370 	}
371 
372 	return &lpddr2_jedec_addressing_table[index];
373 }
374 
375 /*
376  * Find the the right timing table from the array of timing
377  * tables of the device using DDR clock frequency
378  */
379 static const struct lpddr2_timings *get_timings_table(struct emif_data *emif,
380 		u32 freq)
381 {
382 	u32				i, min, max, freq_nearest;
383 	const struct lpddr2_timings	*timings = NULL;
384 	const struct lpddr2_timings	*timings_arr = emif->plat_data->timings;
385 	struct				device *dev = emif->dev;
386 
387 	/* Start with a very high frequency - 1GHz */
388 	freq_nearest = 1000000000;
389 
390 	/*
391 	 * Find the timings table such that:
392 	 *  1. the frequency range covers the required frequency(safe) AND
393 	 *  2. the max_freq is closest to the required frequency(optimal)
394 	 */
395 	for (i = 0; i < emif->plat_data->timings_arr_size; i++) {
396 		max = timings_arr[i].max_freq;
397 		min = timings_arr[i].min_freq;
398 		if ((freq >= min) && (freq <= max) && (max < freq_nearest)) {
399 			freq_nearest = max;
400 			timings = &timings_arr[i];
401 		}
402 	}
403 
404 	if (!timings)
405 		dev_err(dev, "%s: couldn't find timings for - %dHz\n",
406 			__func__, freq);
407 
408 	dev_dbg(dev, "%s: timings table: freq %d, speed bin freq %d\n",
409 		__func__, freq, freq_nearest);
410 
411 	return timings;
412 }
413 
414 static u32 get_sdram_ref_ctrl_shdw(u32 freq,
415 		const struct lpddr2_addressing *addressing)
416 {
417 	u32 ref_ctrl_shdw = 0, val = 0, freq_khz, t_refi;
418 
419 	/* Scale down frequency and t_refi to avoid overflow */
420 	freq_khz = freq / 1000;
421 	t_refi = addressing->tREFI_ns / 100;
422 
423 	/*
424 	 * refresh rate to be set is 'tREFI(in us) * freq in MHz
425 	 * division by 10000 to account for change in units
426 	 */
427 	val = t_refi * freq_khz / 10000;
428 	ref_ctrl_shdw |= val << REFRESH_RATE_SHIFT;
429 
430 	return ref_ctrl_shdw;
431 }
432 
433 static u32 get_sdram_tim_1_shdw(const struct lpddr2_timings *timings,
434 		const struct lpddr2_min_tck *min_tck,
435 		const struct lpddr2_addressing *addressing)
436 {
437 	u32 tim1 = 0, val = 0;
438 
439 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
440 	tim1 |= val << T_WTR_SHIFT;
441 
442 	if (addressing->num_banks == B8)
443 		val = DIV_ROUND_UP(timings->tFAW, t_ck*4);
444 	else
445 		val = max(min_tck->tRRD, DIV_ROUND_UP(timings->tRRD, t_ck));
446 	tim1 |= (val - 1) << T_RRD_SHIFT;
447 
448 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab, t_ck) - 1;
449 	tim1 |= val << T_RC_SHIFT;
450 
451 	val = max(min_tck->tRASmin, DIV_ROUND_UP(timings->tRAS_min, t_ck));
452 	tim1 |= (val - 1) << T_RAS_SHIFT;
453 
454 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
455 	tim1 |= val << T_WR_SHIFT;
456 
457 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD, t_ck)) - 1;
458 	tim1 |= val << T_RCD_SHIFT;
459 
460 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab, t_ck)) - 1;
461 	tim1 |= val << T_RP_SHIFT;
462 
463 	return tim1;
464 }
465 
466 static u32 get_sdram_tim_1_shdw_derated(const struct lpddr2_timings *timings,
467 		const struct lpddr2_min_tck *min_tck,
468 		const struct lpddr2_addressing *addressing)
469 {
470 	u32 tim1 = 0, val = 0;
471 
472 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
473 	tim1 = val << T_WTR_SHIFT;
474 
475 	/*
476 	 * tFAW is approximately 4 times tRRD. So add 1875*4 = 7500ps
477 	 * to tFAW for de-rating
478 	 */
479 	if (addressing->num_banks == B8) {
480 		val = DIV_ROUND_UP(timings->tFAW + 7500, 4 * t_ck) - 1;
481 	} else {
482 		val = DIV_ROUND_UP(timings->tRRD + 1875, t_ck);
483 		val = max(min_tck->tRRD, val) - 1;
484 	}
485 	tim1 |= val << T_RRD_SHIFT;
486 
487 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab + 1875, t_ck);
488 	tim1 |= (val - 1) << T_RC_SHIFT;
489 
490 	val = DIV_ROUND_UP(timings->tRAS_min + 1875, t_ck);
491 	val = max(min_tck->tRASmin, val) - 1;
492 	tim1 |= val << T_RAS_SHIFT;
493 
494 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
495 	tim1 |= val << T_WR_SHIFT;
496 
497 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD + 1875, t_ck));
498 	tim1 |= (val - 1) << T_RCD_SHIFT;
499 
500 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab + 1875, t_ck));
501 	tim1 |= (val - 1) << T_RP_SHIFT;
502 
503 	return tim1;
504 }
505 
506 static u32 get_sdram_tim_2_shdw(const struct lpddr2_timings *timings,
507 		const struct lpddr2_min_tck *min_tck,
508 		const struct lpddr2_addressing *addressing,
509 		u32 type)
510 {
511 	u32 tim2 = 0, val = 0;
512 
513 	val = min_tck->tCKE - 1;
514 	tim2 |= val << T_CKE_SHIFT;
515 
516 	val = max(min_tck->tRTP, DIV_ROUND_UP(timings->tRTP, t_ck)) - 1;
517 	tim2 |= val << T_RTP_SHIFT;
518 
519 	/* tXSNR = tRFCab_ps + 10 ns(tRFCab_ps for LPDDR2). */
520 	val = DIV_ROUND_UP(addressing->tRFCab_ps + 10000, t_ck) - 1;
521 	tim2 |= val << T_XSNR_SHIFT;
522 
523 	/* XSRD same as XSNR for LPDDR2 */
524 	tim2 |= val << T_XSRD_SHIFT;
525 
526 	val = max(min_tck->tXP, DIV_ROUND_UP(timings->tXP, t_ck)) - 1;
527 	tim2 |= val << T_XP_SHIFT;
528 
529 	return tim2;
530 }
531 
532 static u32 get_sdram_tim_3_shdw(const struct lpddr2_timings *timings,
533 		const struct lpddr2_min_tck *min_tck,
534 		const struct lpddr2_addressing *addressing,
535 		u32 type, u32 ip_rev, u32 derated)
536 {
537 	u32 tim3 = 0, val = 0, t_dqsck;
538 
539 	val = timings->tRAS_max_ns / addressing->tREFI_ns - 1;
540 	val = val > 0xF ? 0xF : val;
541 	tim3 |= val << T_RAS_MAX_SHIFT;
542 
543 	val = DIV_ROUND_UP(addressing->tRFCab_ps, t_ck) - 1;
544 	tim3 |= val << T_RFC_SHIFT;
545 
546 	t_dqsck = (derated == EMIF_DERATED_TIMINGS) ?
547 		timings->tDQSCK_max_derated : timings->tDQSCK_max;
548 	if (ip_rev == EMIF_4D5)
549 		val = DIV_ROUND_UP(t_dqsck + 1000, t_ck) - 1;
550 	else
551 		val = DIV_ROUND_UP(t_dqsck, t_ck) - 1;
552 
553 	tim3 |= val << T_TDQSCKMAX_SHIFT;
554 
555 	val = DIV_ROUND_UP(timings->tZQCS, t_ck) - 1;
556 	tim3 |= val << ZQ_ZQCS_SHIFT;
557 
558 	val = DIV_ROUND_UP(timings->tCKESR, t_ck);
559 	val = max(min_tck->tCKESR, val) - 1;
560 	tim3 |= val << T_CKESR_SHIFT;
561 
562 	if (ip_rev == EMIF_4D5) {
563 		tim3 |= (EMIF_T_CSTA - 1) << T_CSTA_SHIFT;
564 
565 		val = DIV_ROUND_UP(EMIF_T_PDLL_UL, 128) - 1;
566 		tim3 |= val << T_PDLL_UL_SHIFT;
567 	}
568 
569 	return tim3;
570 }
571 
572 static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
573 		bool cs1_used, bool cal_resistors_per_cs)
574 {
575 	u32 zq = 0, val = 0;
576 
577 	val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
578 	zq |= val << ZQ_REFINTERVAL_SHIFT;
579 
580 	val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
581 	zq |= val << ZQ_ZQCL_MULT_SHIFT;
582 
583 	val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
584 	zq |= val << ZQ_ZQINIT_MULT_SHIFT;
585 
586 	zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
587 
588 	if (cal_resistors_per_cs)
589 		zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
590 	else
591 		zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
592 
593 	zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
594 
595 	val = cs1_used ? 1 : 0;
596 	zq |= val << ZQ_CS1EN_SHIFT;
597 
598 	return zq;
599 }
600 
601 static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
602 		const struct emif_custom_configs *custom_configs, bool cs1_used,
603 		u32 sdram_io_width, u32 emif_bus_width)
604 {
605 	u32 alert = 0, interval, devcnt;
606 
607 	if (custom_configs && (custom_configs->mask &
608 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
609 		interval = custom_configs->temp_alert_poll_interval_ms;
610 	else
611 		interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
612 
613 	interval *= 1000000;			/* Convert to ns */
614 	interval /= addressing->tREFI_ns;	/* Convert to refresh cycles */
615 	alert |= (interval << TA_REFINTERVAL_SHIFT);
616 
617 	/*
618 	 * sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
619 	 * also to this form and subtract to get TA_DEVCNT, which is
620 	 * in log2(x) form.
621 	 */
622 	emif_bus_width = __fls(emif_bus_width) - 1;
623 	devcnt = emif_bus_width - sdram_io_width;
624 	alert |= devcnt << TA_DEVCNT_SHIFT;
625 
626 	/* DEVWDT is in 'log2(x) - 3' form */
627 	alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
628 
629 	alert |= 1 << TA_SFEXITEN_SHIFT;
630 	alert |= 1 << TA_CS0EN_SHIFT;
631 	alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
632 
633 	return alert;
634 }
635 
636 static u32 get_read_idle_ctrl_shdw(u8 volt_ramp)
637 {
638 	u32 idle = 0, val = 0;
639 
640 	/*
641 	 * Maximum value in normal conditions and increased frequency
642 	 * when voltage is ramping
643 	 */
644 	if (volt_ramp)
645 		val = READ_IDLE_INTERVAL_DVFS / t_ck / 64 - 1;
646 	else
647 		val = 0x1FF;
648 
649 	/*
650 	 * READ_IDLE_CTRL register in EMIF4D has same offset and fields
651 	 * as DLL_CALIB_CTRL in EMIF4D5, so use the same shifts
652 	 */
653 	idle |= val << DLL_CALIB_INTERVAL_SHIFT;
654 	idle |= EMIF_READ_IDLE_LEN_VAL << ACK_WAIT_SHIFT;
655 
656 	return idle;
657 }
658 
659 static u32 get_dll_calib_ctrl_shdw(u8 volt_ramp)
660 {
661 	u32 calib = 0, val = 0;
662 
663 	if (volt_ramp == DDR_VOLTAGE_RAMPING)
664 		val = DLL_CALIB_INTERVAL_DVFS / t_ck / 16 - 1;
665 	else
666 		val = 0; /* Disabled when voltage is stable */
667 
668 	calib |= val << DLL_CALIB_INTERVAL_SHIFT;
669 	calib |= DLL_CALIB_ACK_WAIT_VAL << ACK_WAIT_SHIFT;
670 
671 	return calib;
672 }
673 
674 static u32 get_ddr_phy_ctrl_1_attilaphy_4d(const struct lpddr2_timings *timings,
675 	u32 freq, u8 RL)
676 {
677 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_ATTILAPHY, val = 0;
678 
679 	val = RL + DIV_ROUND_UP(timings->tDQSCK_max, t_ck) - 1;
680 	phy |= val << READ_LATENCY_SHIFT_4D;
681 
682 	if (freq <= 100000000)
683 		val = EMIF_DLL_SLAVE_DLY_CTRL_100_MHZ_AND_LESS_ATTILAPHY;
684 	else if (freq <= 200000000)
685 		val = EMIF_DLL_SLAVE_DLY_CTRL_200_MHZ_ATTILAPHY;
686 	else
687 		val = EMIF_DLL_SLAVE_DLY_CTRL_400_MHZ_ATTILAPHY;
688 
689 	phy |= val << DLL_SLAVE_DLY_CTRL_SHIFT_4D;
690 
691 	return phy;
692 }
693 
694 static u32 get_phy_ctrl_1_intelliphy_4d5(u32 freq, u8 cl)
695 {
696 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_INTELLIPHY, half_delay;
697 
698 	/*
699 	 * DLL operates at 266 MHz. If DDR frequency is near 266 MHz,
700 	 * half-delay is not needed else set half-delay
701 	 */
702 	if (freq >= 265000000 && freq < 267000000)
703 		half_delay = 0;
704 	else
705 		half_delay = 1;
706 
707 	phy |= half_delay << DLL_HALF_DELAY_SHIFT_4D5;
708 	phy |= ((cl + DIV_ROUND_UP(EMIF_PHY_TOTAL_READ_LATENCY_INTELLIPHY_PS,
709 			t_ck) - 1) << READ_LATENCY_SHIFT_4D5);
710 
711 	return phy;
712 }
713 
714 static u32 get_ext_phy_ctrl_2_intelliphy_4d5(void)
715 {
716 	u32 fifo_we_slave_ratio;
717 
718 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
719 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
720 
721 	return fifo_we_slave_ratio | fifo_we_slave_ratio << 11 |
722 		fifo_we_slave_ratio << 22;
723 }
724 
725 static u32 get_ext_phy_ctrl_3_intelliphy_4d5(void)
726 {
727 	u32 fifo_we_slave_ratio;
728 
729 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
730 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
731 
732 	return fifo_we_slave_ratio >> 10 | fifo_we_slave_ratio << 1 |
733 		fifo_we_slave_ratio << 12 | fifo_we_slave_ratio << 23;
734 }
735 
736 static u32 get_ext_phy_ctrl_4_intelliphy_4d5(void)
737 {
738 	u32 fifo_we_slave_ratio;
739 
740 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
741 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
742 
743 	return fifo_we_slave_ratio >> 9 | fifo_we_slave_ratio << 2 |
744 		fifo_we_slave_ratio << 13;
745 }
746 
747 static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
748 {
749 	u32 pwr_mgmt_ctrl	= 0, timeout;
750 	u32 lpmode		= EMIF_LP_MODE_SELF_REFRESH;
751 	u32 timeout_perf	= EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
752 	u32 timeout_pwr		= EMIF_LP_MODE_TIMEOUT_POWER;
753 	u32 freq_threshold	= EMIF_LP_MODE_FREQ_THRESHOLD;
754 	u32 mask;
755 	u8 shift;
756 
757 	struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
758 
759 	if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
760 		lpmode		= cust_cfgs->lpmode;
761 		timeout_perf	= cust_cfgs->lpmode_timeout_performance;
762 		timeout_pwr	= cust_cfgs->lpmode_timeout_power;
763 		freq_threshold  = cust_cfgs->lpmode_freq_threshold;
764 	}
765 
766 	/* Timeout based on DDR frequency */
767 	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
768 
769 	/*
770 	 * The value to be set in register is "log2(timeout) - 3"
771 	 * if timeout < 16 load 0 in register
772 	 * if timeout is not a power of 2, round to next highest power of 2
773 	 */
774 	if (timeout < 16) {
775 		timeout = 0;
776 	} else {
777 		if (timeout & (timeout - 1))
778 			timeout <<= 1;
779 		timeout = __fls(timeout) - 3;
780 	}
781 
782 	switch (lpmode) {
783 	case EMIF_LP_MODE_CLOCK_STOP:
784 		shift = CS_TIM_SHIFT;
785 		mask = CS_TIM_MASK;
786 		break;
787 	case EMIF_LP_MODE_SELF_REFRESH:
788 		/* Workaround for errata i735 */
789 		if (timeout < 6)
790 			timeout = 6;
791 
792 		shift = SR_TIM_SHIFT;
793 		mask = SR_TIM_MASK;
794 		break;
795 	case EMIF_LP_MODE_PWR_DN:
796 		shift = PD_TIM_SHIFT;
797 		mask = PD_TIM_MASK;
798 		break;
799 	case EMIF_LP_MODE_DISABLE:
800 	default:
801 		mask = 0;
802 		shift = 0;
803 		break;
804 	}
805 	/* Round to maximum in case of overflow, BUT warn! */
806 	if (lpmode != EMIF_LP_MODE_DISABLE && timeout > mask >> shift) {
807 		pr_err("TIMEOUT Overflow - lpmode=%d perf=%d pwr=%d freq=%d\n",
808 		       lpmode,
809 		       timeout_perf,
810 		       timeout_pwr,
811 		       freq_threshold);
812 		WARN(1, "timeout=0x%02x greater than 0x%02x. Using max\n",
813 		     timeout, mask >> shift);
814 		timeout = mask >> shift;
815 	}
816 
817 	/* Setup required timing */
818 	pwr_mgmt_ctrl = (timeout << shift) & mask;
819 	/* setup a default mask for rest of the modes */
820 	pwr_mgmt_ctrl |= (SR_TIM_MASK | CS_TIM_MASK | PD_TIM_MASK) &
821 			  ~mask;
822 
823 	/* No CS_TIM in EMIF_4D5 */
824 	if (ip_rev == EMIF_4D5)
825 		pwr_mgmt_ctrl &= ~CS_TIM_MASK;
826 
827 	pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
828 
829 	return pwr_mgmt_ctrl;
830 }
831 
832 /*
833  * Get the temperature level of the EMIF instance:
834  * Reads the MR4 register of attached SDRAM parts to find out the temperature
835  * level. If there are two parts attached(one on each CS), then the temperature
836  * level for the EMIF instance is the higher of the two temperatures.
837  */
838 static void get_temperature_level(struct emif_data *emif)
839 {
840 	u32		temp, temperature_level;
841 	void __iomem	*base;
842 
843 	base = emif->base;
844 
845 	/* Read mode register 4 */
846 	writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
847 	temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
848 	temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
849 				MR4_SDRAM_REF_RATE_SHIFT;
850 
851 	if (emif->plat_data->device_info->cs1_used) {
852 		writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
853 		temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
854 		temp = (temp & MR4_SDRAM_REF_RATE_MASK)
855 				>> MR4_SDRAM_REF_RATE_SHIFT;
856 		temperature_level = max(temp, temperature_level);
857 	}
858 
859 	/* treat everything less than nominal(3) in MR4 as nominal */
860 	if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
861 		temperature_level = SDRAM_TEMP_NOMINAL;
862 
863 	/* if we get reserved value in MR4 persist with the existing value */
864 	if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
865 		emif->temperature_level = temperature_level;
866 }
867 
868 /*
869  * Program EMIF shadow registers that are not dependent on temperature
870  * or voltage
871  */
872 static void setup_registers(struct emif_data *emif, struct emif_regs *regs)
873 {
874 	void __iomem	*base = emif->base;
875 
876 	writel(regs->sdram_tim2_shdw, base + EMIF_SDRAM_TIMING_2_SHDW);
877 	writel(regs->phy_ctrl_1_shdw, base + EMIF_DDR_PHY_CTRL_1_SHDW);
878 	writel(regs->pwr_mgmt_ctrl_shdw,
879 	       base + EMIF_POWER_MANAGEMENT_CTRL_SHDW);
880 
881 	/* Settings specific for EMIF4D5 */
882 	if (emif->plat_data->ip_rev != EMIF_4D5)
883 		return;
884 	writel(regs->ext_phy_ctrl_2_shdw, base + EMIF_EXT_PHY_CTRL_2_SHDW);
885 	writel(regs->ext_phy_ctrl_3_shdw, base + EMIF_EXT_PHY_CTRL_3_SHDW);
886 	writel(regs->ext_phy_ctrl_4_shdw, base + EMIF_EXT_PHY_CTRL_4_SHDW);
887 }
888 
889 /*
890  * When voltage ramps dll calibration and forced read idle should
891  * happen more often
892  */
893 static void setup_volt_sensitive_regs(struct emif_data *emif,
894 		struct emif_regs *regs, u32 volt_state)
895 {
896 	u32		calib_ctrl;
897 	void __iomem	*base = emif->base;
898 
899 	/*
900 	 * EMIF_READ_IDLE_CTRL in EMIF4D refers to the same register as
901 	 * EMIF_DLL_CALIB_CTRL in EMIF4D5 and dll_calib_ctrl_shadow_*
902 	 * is an alias of the respective read_idle_ctrl_shdw_* (members of
903 	 * a union). So, the below code takes care of both cases
904 	 */
905 	if (volt_state == DDR_VOLTAGE_RAMPING)
906 		calib_ctrl = regs->dll_calib_ctrl_shdw_volt_ramp;
907 	else
908 		calib_ctrl = regs->dll_calib_ctrl_shdw_normal;
909 
910 	writel(calib_ctrl, base + EMIF_DLL_CALIB_CTRL_SHDW);
911 }
912 
913 /*
914  * setup_temperature_sensitive_regs() - set the timings for temperature
915  * sensitive registers. This happens once at initialisation time based
916  * on the temperature at boot time and subsequently based on the temperature
917  * alert interrupt. Temperature alert can happen when the temperature
918  * increases or drops. So this function can have the effect of either
919  * derating the timings or going back to nominal values.
920  */
921 static void setup_temperature_sensitive_regs(struct emif_data *emif,
922 		struct emif_regs *regs)
923 {
924 	u32		tim1, tim3, ref_ctrl, type;
925 	void __iomem	*base = emif->base;
926 	u32		temperature;
927 
928 	type = emif->plat_data->device_info->type;
929 
930 	tim1 = regs->sdram_tim1_shdw;
931 	tim3 = regs->sdram_tim3_shdw;
932 	ref_ctrl = regs->ref_ctrl_shdw;
933 
934 	/* No de-rating for non-lpddr2 devices */
935 	if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
936 		goto out;
937 
938 	temperature = emif->temperature_level;
939 	if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
940 		ref_ctrl = regs->ref_ctrl_shdw_derated;
941 	} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
942 		tim1 = regs->sdram_tim1_shdw_derated;
943 		tim3 = regs->sdram_tim3_shdw_derated;
944 		ref_ctrl = regs->ref_ctrl_shdw_derated;
945 	}
946 
947 out:
948 	writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
949 	writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
950 	writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
951 }
952 
953 static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
954 {
955 	u32		old_temp_level;
956 	irqreturn_t	ret = IRQ_HANDLED;
957 	struct emif_custom_configs *custom_configs;
958 
959 	spin_lock_irqsave(&emif_lock, irq_state);
960 	old_temp_level = emif->temperature_level;
961 	get_temperature_level(emif);
962 
963 	if (unlikely(emif->temperature_level == old_temp_level)) {
964 		goto out;
965 	} else if (!emif->curr_regs) {
966 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
967 		goto out;
968 	}
969 
970 	custom_configs = emif->plat_data->custom_configs;
971 
972 	/*
973 	 * IF we detect higher than "nominal rating" from DDR sensor
974 	 * on an unsupported DDR part, shutdown system
975 	 */
976 	if (custom_configs && !(custom_configs->mask &
977 				EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART)) {
978 		if (emif->temperature_level >= SDRAM_TEMP_HIGH_DERATE_REFRESH) {
979 			dev_err(emif->dev,
980 				"%s:NOT Extended temperature capable memory."
981 				"Converting MR4=0x%02x as shutdown event\n",
982 				__func__, emif->temperature_level);
983 			/*
984 			 * Temperature far too high - do kernel_power_off()
985 			 * from thread context
986 			 */
987 			emif->temperature_level = SDRAM_TEMP_VERY_HIGH_SHUTDOWN;
988 			ret = IRQ_WAKE_THREAD;
989 			goto out;
990 		}
991 	}
992 
993 	if (emif->temperature_level < old_temp_level ||
994 		emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
995 		/*
996 		 * Temperature coming down - defer handling to thread OR
997 		 * Temperature far too high - do kernel_power_off() from
998 		 * thread context
999 		 */
1000 		ret = IRQ_WAKE_THREAD;
1001 	} else {
1002 		/* Temperature is going up - handle immediately */
1003 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
1004 		do_freq_update();
1005 	}
1006 
1007 out:
1008 	spin_unlock_irqrestore(&emif_lock, irq_state);
1009 	return ret;
1010 }
1011 
1012 static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
1013 {
1014 	u32			interrupts;
1015 	struct emif_data	*emif = dev_id;
1016 	void __iomem		*base = emif->base;
1017 	struct device		*dev = emif->dev;
1018 	irqreturn_t		ret = IRQ_HANDLED;
1019 
1020 	/* Save the status and clear it */
1021 	interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1022 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1023 
1024 	/*
1025 	 * Handle temperature alert
1026 	 * Temperature alert should be same for all ports
1027 	 * So, it's enough to process it only for one of the ports
1028 	 */
1029 	if (interrupts & TA_SYS_MASK)
1030 		ret = handle_temp_alert(base, emif);
1031 
1032 	if (interrupts & ERR_SYS_MASK)
1033 		dev_err(dev, "Access error from SYS port - %x\n", interrupts);
1034 
1035 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1036 		/* Save the status and clear it */
1037 		interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
1038 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
1039 
1040 		if (interrupts & ERR_LL_MASK)
1041 			dev_err(dev, "Access error from LL port - %x\n",
1042 				interrupts);
1043 	}
1044 
1045 	return ret;
1046 }
1047 
1048 static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
1049 {
1050 	struct emif_data	*emif = dev_id;
1051 
1052 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
1053 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1054 
1055 		/* If we have Power OFF ability, use it, else try restarting */
1056 		if (pm_power_off) {
1057 			kernel_power_off();
1058 		} else {
1059 			WARN(1, "FIXME: NO pm_power_off!!! trying restart\n");
1060 			kernel_restart("SDRAM Over-temp Emergency restart");
1061 		}
1062 		return IRQ_HANDLED;
1063 	}
1064 
1065 	spin_lock_irqsave(&emif_lock, irq_state);
1066 
1067 	if (emif->curr_regs) {
1068 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
1069 		do_freq_update();
1070 	} else {
1071 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
1072 	}
1073 
1074 	spin_unlock_irqrestore(&emif_lock, irq_state);
1075 
1076 	return IRQ_HANDLED;
1077 }
1078 
1079 static void clear_all_interrupts(struct emif_data *emif)
1080 {
1081 	void __iomem	*base = emif->base;
1082 
1083 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
1084 		base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1085 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1086 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
1087 			base + EMIF_LL_OCP_INTERRUPT_STATUS);
1088 }
1089 
1090 static void disable_and_clear_all_interrupts(struct emif_data *emif)
1091 {
1092 	void __iomem		*base = emif->base;
1093 
1094 	/* Disable all interrupts */
1095 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
1096 		base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
1097 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1098 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
1099 			base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
1100 
1101 	/* Clear all interrupts */
1102 	clear_all_interrupts(emif);
1103 }
1104 
1105 static int __init_or_module setup_interrupts(struct emif_data *emif, u32 irq)
1106 {
1107 	u32		interrupts, type;
1108 	void __iomem	*base = emif->base;
1109 
1110 	type = emif->plat_data->device_info->type;
1111 
1112 	clear_all_interrupts(emif);
1113 
1114 	/* Enable interrupts for SYS interface */
1115 	interrupts = EN_ERR_SYS_MASK;
1116 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
1117 		interrupts |= EN_TA_SYS_MASK;
1118 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
1119 
1120 	/* Enable interrupts for LL interface */
1121 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1122 		/* TA need not be enabled for LL */
1123 		interrupts = EN_ERR_LL_MASK;
1124 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
1125 	}
1126 
1127 	/* setup IRQ handlers */
1128 	return devm_request_threaded_irq(emif->dev, irq,
1129 				    emif_interrupt_handler,
1130 				    emif_threaded_isr,
1131 				    0, dev_name(emif->dev),
1132 				    emif);
1133 
1134 }
1135 
1136 static void __init_or_module emif_onetime_settings(struct emif_data *emif)
1137 {
1138 	u32				pwr_mgmt_ctrl, zq, temp_alert_cfg;
1139 	void __iomem			*base = emif->base;
1140 	const struct lpddr2_addressing	*addressing;
1141 	const struct ddr_device_info	*device_info;
1142 
1143 	device_info = emif->plat_data->device_info;
1144 	addressing = get_addressing_table(device_info);
1145 
1146 	/*
1147 	 * Init power management settings
1148 	 * We don't know the frequency yet. Use a high frequency
1149 	 * value for a conservative timeout setting
1150 	 */
1151 	pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
1152 			emif->plat_data->ip_rev);
1153 	emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
1154 	writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
1155 
1156 	/* Init ZQ calibration settings */
1157 	zq = get_zq_config_reg(addressing, device_info->cs1_used,
1158 		device_info->cal_resistors_per_cs);
1159 	writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
1160 
1161 	/* Check temperature level temperature level*/
1162 	get_temperature_level(emif);
1163 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
1164 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1165 
1166 	/* Init temperature polling */
1167 	temp_alert_cfg = get_temp_alert_config(addressing,
1168 		emif->plat_data->custom_configs, device_info->cs1_used,
1169 		device_info->io_width, get_emif_bus_width(emif));
1170 	writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
1171 
1172 	/*
1173 	 * Program external PHY control registers that are not frequency
1174 	 * dependent
1175 	 */
1176 	if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
1177 		return;
1178 	writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
1179 	writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
1180 	writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
1181 	writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
1182 	writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
1183 	writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
1184 	writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
1185 	writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
1186 	writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
1187 	writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
1188 	writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
1189 	writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
1190 	writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
1191 	writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
1192 	writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
1193 	writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
1194 	writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
1195 	writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
1196 	writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
1197 	writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
1198 	writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
1199 }
1200 
1201 static void get_default_timings(struct emif_data *emif)
1202 {
1203 	struct emif_platform_data *pd = emif->plat_data;
1204 
1205 	pd->timings		= lpddr2_jedec_timings;
1206 	pd->timings_arr_size	= ARRAY_SIZE(lpddr2_jedec_timings);
1207 
1208 	dev_warn(emif->dev, "%s: using default timings\n", __func__);
1209 }
1210 
1211 static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
1212 		u32 ip_rev, struct device *dev)
1213 {
1214 	int valid;
1215 
1216 	valid = (type == DDR_TYPE_LPDDR2_S4 ||
1217 			type == DDR_TYPE_LPDDR2_S2)
1218 		&& (density >= DDR_DENSITY_64Mb
1219 			&& density <= DDR_DENSITY_8Gb)
1220 		&& (io_width >= DDR_IO_WIDTH_8
1221 			&& io_width <= DDR_IO_WIDTH_32);
1222 
1223 	/* Combinations of EMIF and PHY revisions that we support today */
1224 	switch (ip_rev) {
1225 	case EMIF_4D:
1226 		valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
1227 		break;
1228 	case EMIF_4D5:
1229 		valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
1230 		break;
1231 	default:
1232 		valid = 0;
1233 	}
1234 
1235 	if (!valid)
1236 		dev_err(dev, "%s: invalid DDR details\n", __func__);
1237 	return valid;
1238 }
1239 
1240 static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
1241 		struct device *dev)
1242 {
1243 	int valid = 1;
1244 
1245 	if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
1246 		(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
1247 		valid = cust_cfgs->lpmode_freq_threshold &&
1248 			cust_cfgs->lpmode_timeout_performance &&
1249 			cust_cfgs->lpmode_timeout_power;
1250 
1251 	if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
1252 		valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
1253 
1254 	if (!valid)
1255 		dev_warn(dev, "%s: invalid custom configs\n", __func__);
1256 
1257 	return valid;
1258 }
1259 
1260 #if defined(CONFIG_OF)
1261 static void __init_or_module of_get_custom_configs(struct device_node *np_emif,
1262 		struct emif_data *emif)
1263 {
1264 	struct emif_custom_configs	*cust_cfgs = NULL;
1265 	int				len;
1266 	const __be32			*lpmode, *poll_intvl;
1267 
1268 	lpmode = of_get_property(np_emif, "low-power-mode", &len);
1269 	poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
1270 
1271 	if (lpmode || poll_intvl)
1272 		cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
1273 			GFP_KERNEL);
1274 
1275 	if (!cust_cfgs)
1276 		return;
1277 
1278 	if (lpmode) {
1279 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
1280 		cust_cfgs->lpmode = be32_to_cpup(lpmode);
1281 		of_property_read_u32(np_emif,
1282 				"low-power-mode-timeout-performance",
1283 				&cust_cfgs->lpmode_timeout_performance);
1284 		of_property_read_u32(np_emif,
1285 				"low-power-mode-timeout-power",
1286 				&cust_cfgs->lpmode_timeout_power);
1287 		of_property_read_u32(np_emif,
1288 				"low-power-mode-freq-threshold",
1289 				&cust_cfgs->lpmode_freq_threshold);
1290 	}
1291 
1292 	if (poll_intvl) {
1293 		cust_cfgs->mask |=
1294 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
1295 		cust_cfgs->temp_alert_poll_interval_ms =
1296 						be32_to_cpup(poll_intvl);
1297 	}
1298 
1299 	if (of_find_property(np_emif, "extended-temp-part", &len))
1300 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART;
1301 
1302 	if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
1303 		devm_kfree(emif->dev, cust_cfgs);
1304 		return;
1305 	}
1306 
1307 	emif->plat_data->custom_configs = cust_cfgs;
1308 }
1309 
1310 static void __init_or_module of_get_ddr_info(struct device_node *np_emif,
1311 		struct device_node *np_ddr,
1312 		struct ddr_device_info *dev_info)
1313 {
1314 	u32 density = 0, io_width = 0;
1315 	int len;
1316 
1317 	if (of_find_property(np_emif, "cs1-used", &len))
1318 		dev_info->cs1_used = true;
1319 
1320 	if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
1321 		dev_info->cal_resistors_per_cs = true;
1322 
1323 	if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s4"))
1324 		dev_info->type = DDR_TYPE_LPDDR2_S4;
1325 	else if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s2"))
1326 		dev_info->type = DDR_TYPE_LPDDR2_S2;
1327 
1328 	of_property_read_u32(np_ddr, "density", &density);
1329 	of_property_read_u32(np_ddr, "io-width", &io_width);
1330 
1331 	/* Convert from density in Mb to the density encoding in jedc_ddr.h */
1332 	if (density & (density - 1))
1333 		dev_info->density = 0;
1334 	else
1335 		dev_info->density = __fls(density) - 5;
1336 
1337 	/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
1338 	if (io_width & (io_width - 1))
1339 		dev_info->io_width = 0;
1340 	else
1341 		dev_info->io_width = __fls(io_width) - 1;
1342 }
1343 
1344 static struct emif_data * __init_or_module of_get_memory_device_details(
1345 		struct device_node *np_emif, struct device *dev)
1346 {
1347 	struct emif_data		*emif = NULL;
1348 	struct ddr_device_info		*dev_info = NULL;
1349 	struct emif_platform_data	*pd = NULL;
1350 	struct device_node		*np_ddr;
1351 	int				len;
1352 
1353 	np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
1354 	if (!np_ddr)
1355 		goto error;
1356 	emif	= devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
1357 	pd	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1358 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1359 
1360 	if (!emif || !pd || !dev_info) {
1361 		dev_err(dev, "%s: Out of memory!!\n",
1362 			__func__);
1363 		goto error;
1364 	}
1365 
1366 	emif->plat_data		= pd;
1367 	pd->device_info		= dev_info;
1368 	emif->dev		= dev;
1369 	emif->np_ddr		= np_ddr;
1370 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1371 
1372 	if (of_device_is_compatible(np_emif, "ti,emif-4d"))
1373 		emif->plat_data->ip_rev = EMIF_4D;
1374 	else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
1375 		emif->plat_data->ip_rev = EMIF_4D5;
1376 
1377 	of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
1378 
1379 	if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
1380 		pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
1381 
1382 	of_get_ddr_info(np_emif, np_ddr, dev_info);
1383 	if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
1384 			pd->device_info->io_width, pd->phy_type, pd->ip_rev,
1385 			emif->dev)) {
1386 		dev_err(dev, "%s: invalid device data!!\n", __func__);
1387 		goto error;
1388 	}
1389 	/*
1390 	 * For EMIF instances other than EMIF1 see if the devices connected
1391 	 * are exactly same as on EMIF1(which is typically the case). If so,
1392 	 * mark it as a duplicate of EMIF1. This will save some memory and
1393 	 * computation.
1394 	 */
1395 	if (emif1 && emif1->np_ddr == np_ddr) {
1396 		emif->duplicate = true;
1397 		goto out;
1398 	} else if (emif1) {
1399 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1400 			__func__);
1401 	}
1402 
1403 	of_get_custom_configs(np_emif, emif);
1404 	emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
1405 					emif->plat_data->device_info->type,
1406 					&emif->plat_data->timings_arr_size);
1407 
1408 	emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
1409 	goto out;
1410 
1411 error:
1412 	return NULL;
1413 out:
1414 	return emif;
1415 }
1416 
1417 #else
1418 
1419 static struct emif_data * __init_or_module of_get_memory_device_details(
1420 		struct device_node *np_emif, struct device *dev)
1421 {
1422 	return NULL;
1423 }
1424 #endif
1425 
1426 static struct emif_data *__init_or_module get_device_details(
1427 		struct platform_device *pdev)
1428 {
1429 	u32				size;
1430 	struct emif_data		*emif = NULL;
1431 	struct ddr_device_info		*dev_info;
1432 	struct emif_custom_configs	*cust_cfgs;
1433 	struct emif_platform_data	*pd;
1434 	struct device			*dev;
1435 	void				*temp;
1436 
1437 	pd = pdev->dev.platform_data;
1438 	dev = &pdev->dev;
1439 
1440 	if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
1441 			pd->device_info->density, pd->device_info->io_width,
1442 			pd->phy_type, pd->ip_rev, dev))) {
1443 		dev_err(dev, "%s: invalid device data\n", __func__);
1444 		goto error;
1445 	}
1446 
1447 	emif	= devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
1448 	temp	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1449 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1450 
1451 	if (!emif || !pd || !dev_info) {
1452 		dev_err(dev, "%s:%d: allocation error\n", __func__, __LINE__);
1453 		goto error;
1454 	}
1455 
1456 	memcpy(temp, pd, sizeof(*pd));
1457 	pd = temp;
1458 	memcpy(dev_info, pd->device_info, sizeof(*dev_info));
1459 
1460 	pd->device_info		= dev_info;
1461 	emif->plat_data		= pd;
1462 	emif->dev		= dev;
1463 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1464 
1465 	/*
1466 	 * For EMIF instances other than EMIF1 see if the devices connected
1467 	 * are exactly same as on EMIF1(which is typically the case). If so,
1468 	 * mark it as a duplicate of EMIF1 and skip copying timings data.
1469 	 * This will save some memory and some computation later.
1470 	 */
1471 	emif->duplicate = emif1 && (memcmp(dev_info,
1472 		emif1->plat_data->device_info,
1473 		sizeof(struct ddr_device_info)) == 0);
1474 
1475 	if (emif->duplicate) {
1476 		pd->timings = NULL;
1477 		pd->min_tck = NULL;
1478 		goto out;
1479 	} else if (emif1) {
1480 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1481 			__func__);
1482 	}
1483 
1484 	/*
1485 	 * Copy custom configs - ignore allocation error, if any, as
1486 	 * custom_configs is not very critical
1487 	 */
1488 	cust_cfgs = pd->custom_configs;
1489 	if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
1490 		temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
1491 		if (temp)
1492 			memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
1493 		else
1494 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1495 				__LINE__);
1496 		pd->custom_configs = temp;
1497 	}
1498 
1499 	/*
1500 	 * Copy timings and min-tck values from platform data. If it is not
1501 	 * available or if memory allocation fails, use JEDEC defaults
1502 	 */
1503 	size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
1504 	if (pd->timings) {
1505 		temp = devm_kzalloc(dev, size, GFP_KERNEL);
1506 		if (temp) {
1507 			memcpy(temp, pd->timings, size);
1508 			pd->timings = temp;
1509 		} else {
1510 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1511 				__LINE__);
1512 			get_default_timings(emif);
1513 		}
1514 	} else {
1515 		get_default_timings(emif);
1516 	}
1517 
1518 	if (pd->min_tck) {
1519 		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
1520 		if (temp) {
1521 			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
1522 			pd->min_tck = temp;
1523 		} else {
1524 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1525 				__LINE__);
1526 			pd->min_tck = &lpddr2_jedec_min_tck;
1527 		}
1528 	} else {
1529 		pd->min_tck = &lpddr2_jedec_min_tck;
1530 	}
1531 
1532 out:
1533 	return emif;
1534 
1535 error:
1536 	return NULL;
1537 }
1538 
1539 static int __init_or_module emif_probe(struct platform_device *pdev)
1540 {
1541 	struct emif_data	*emif;
1542 	struct resource		*res;
1543 	int			irq;
1544 
1545 	if (pdev->dev.of_node)
1546 		emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
1547 	else
1548 		emif = get_device_details(pdev);
1549 
1550 	if (!emif) {
1551 		pr_err("%s: error getting device data\n", __func__);
1552 		goto error;
1553 	}
1554 
1555 	list_add(&emif->node, &device_list);
1556 	emif->addressing = get_addressing_table(emif->plat_data->device_info);
1557 
1558 	/* Save pointers to each other in emif and device structures */
1559 	emif->dev = &pdev->dev;
1560 	platform_set_drvdata(pdev, emif);
1561 
1562 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1563 	emif->base = devm_ioremap_resource(emif->dev, res);
1564 	if (IS_ERR(emif->base))
1565 		goto error;
1566 
1567 	irq = platform_get_irq(pdev, 0);
1568 	if (irq < 0) {
1569 		dev_err(emif->dev, "%s: error getting IRQ resource - %d\n",
1570 			__func__, irq);
1571 		goto error;
1572 	}
1573 
1574 	emif_onetime_settings(emif);
1575 	emif_debugfs_init(emif);
1576 	disable_and_clear_all_interrupts(emif);
1577 	setup_interrupts(emif, irq);
1578 
1579 	/* One-time actions taken on probing the first device */
1580 	if (!emif1) {
1581 		emif1 = emif;
1582 		spin_lock_init(&emif_lock);
1583 
1584 		/*
1585 		 * TODO: register notifiers for frequency and voltage
1586 		 * change here once the respective frameworks are
1587 		 * available
1588 		 */
1589 	}
1590 
1591 	dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
1592 		__func__, emif->base, irq);
1593 
1594 	return 0;
1595 error:
1596 	return -ENODEV;
1597 }
1598 
1599 static int __exit emif_remove(struct platform_device *pdev)
1600 {
1601 	struct emif_data *emif = platform_get_drvdata(pdev);
1602 
1603 	emif_debugfs_exit(emif);
1604 
1605 	return 0;
1606 }
1607 
1608 static void emif_shutdown(struct platform_device *pdev)
1609 {
1610 	struct emif_data	*emif = platform_get_drvdata(pdev);
1611 
1612 	disable_and_clear_all_interrupts(emif);
1613 }
1614 
1615 static int get_emif_reg_values(struct emif_data *emif, u32 freq,
1616 		struct emif_regs *regs)
1617 {
1618 	u32				cs1_used, ip_rev, phy_type;
1619 	u32				cl, type;
1620 	const struct lpddr2_timings	*timings;
1621 	const struct lpddr2_min_tck	*min_tck;
1622 	const struct ddr_device_info	*device_info;
1623 	const struct lpddr2_addressing	*addressing;
1624 	struct emif_data		*emif_for_calc;
1625 	struct device			*dev;
1626 	const struct emif_custom_configs *custom_configs;
1627 
1628 	dev = emif->dev;
1629 	/*
1630 	 * If the devices on this EMIF instance is duplicate of EMIF1,
1631 	 * use EMIF1 details for the calculation
1632 	 */
1633 	emif_for_calc	= emif->duplicate ? emif1 : emif;
1634 	timings		= get_timings_table(emif_for_calc, freq);
1635 	addressing	= emif_for_calc->addressing;
1636 	if (!timings || !addressing) {
1637 		dev_err(dev, "%s: not enough data available for %dHz",
1638 			__func__, freq);
1639 		return -1;
1640 	}
1641 
1642 	device_info	= emif_for_calc->plat_data->device_info;
1643 	type		= device_info->type;
1644 	cs1_used	= device_info->cs1_used;
1645 	ip_rev		= emif_for_calc->plat_data->ip_rev;
1646 	phy_type	= emif_for_calc->plat_data->phy_type;
1647 
1648 	min_tck		= emif_for_calc->plat_data->min_tck;
1649 	custom_configs	= emif_for_calc->plat_data->custom_configs;
1650 
1651 	set_ddr_clk_period(freq);
1652 
1653 	regs->ref_ctrl_shdw = get_sdram_ref_ctrl_shdw(freq, addressing);
1654 	regs->sdram_tim1_shdw = get_sdram_tim_1_shdw(timings, min_tck,
1655 			addressing);
1656 	regs->sdram_tim2_shdw = get_sdram_tim_2_shdw(timings, min_tck,
1657 			addressing, type);
1658 	regs->sdram_tim3_shdw = get_sdram_tim_3_shdw(timings, min_tck,
1659 		addressing, type, ip_rev, EMIF_NORMAL_TIMINGS);
1660 
1661 	cl = get_cl(emif);
1662 
1663 	if (phy_type == EMIF_PHY_TYPE_ATTILAPHY && ip_rev == EMIF_4D) {
1664 		regs->phy_ctrl_1_shdw = get_ddr_phy_ctrl_1_attilaphy_4d(
1665 			timings, freq, cl);
1666 	} else if (phy_type == EMIF_PHY_TYPE_INTELLIPHY && ip_rev == EMIF_4D5) {
1667 		regs->phy_ctrl_1_shdw = get_phy_ctrl_1_intelliphy_4d5(freq, cl);
1668 		regs->ext_phy_ctrl_2_shdw = get_ext_phy_ctrl_2_intelliphy_4d5();
1669 		regs->ext_phy_ctrl_3_shdw = get_ext_phy_ctrl_3_intelliphy_4d5();
1670 		regs->ext_phy_ctrl_4_shdw = get_ext_phy_ctrl_4_intelliphy_4d5();
1671 	} else {
1672 		return -1;
1673 	}
1674 
1675 	/* Only timeout values in pwr_mgmt_ctrl_shdw register */
1676 	regs->pwr_mgmt_ctrl_shdw =
1677 		get_pwr_mgmt_ctrl(freq, emif_for_calc, ip_rev) &
1678 		(CS_TIM_MASK | SR_TIM_MASK | PD_TIM_MASK);
1679 
1680 	if (ip_rev & EMIF_4D) {
1681 		regs->read_idle_ctrl_shdw_normal =
1682 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_STABLE);
1683 
1684 		regs->read_idle_ctrl_shdw_volt_ramp =
1685 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1686 	} else if (ip_rev & EMIF_4D5) {
1687 		regs->dll_calib_ctrl_shdw_normal =
1688 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_STABLE);
1689 
1690 		regs->dll_calib_ctrl_shdw_volt_ramp =
1691 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1692 	}
1693 
1694 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
1695 		regs->ref_ctrl_shdw_derated = get_sdram_ref_ctrl_shdw(freq / 4,
1696 			addressing);
1697 
1698 		regs->sdram_tim1_shdw_derated =
1699 			get_sdram_tim_1_shdw_derated(timings, min_tck,
1700 				addressing);
1701 
1702 		regs->sdram_tim3_shdw_derated = get_sdram_tim_3_shdw(timings,
1703 			min_tck, addressing, type, ip_rev,
1704 			EMIF_DERATED_TIMINGS);
1705 	}
1706 
1707 	regs->freq = freq;
1708 
1709 	return 0;
1710 }
1711 
1712 /*
1713  * get_regs() - gets the cached emif_regs structure for a given EMIF instance
1714  * given frequency(freq):
1715  *
1716  * As an optimisation, every EMIF instance other than EMIF1 shares the
1717  * register cache with EMIF1 if the devices connected on this instance
1718  * are same as that on EMIF1(indicated by the duplicate flag)
1719  *
1720  * If we do not have an entry corresponding to the frequency given, we
1721  * allocate a new entry and calculate the values
1722  *
1723  * Upon finding the right reg dump, save it in curr_regs. It can be
1724  * directly used for thermal de-rating and voltage ramping changes.
1725  */
1726 static struct emif_regs *get_regs(struct emif_data *emif, u32 freq)
1727 {
1728 	int			i;
1729 	struct emif_regs	**regs_cache;
1730 	struct emif_regs	*regs = NULL;
1731 	struct device		*dev;
1732 
1733 	dev = emif->dev;
1734 	if (emif->curr_regs && emif->curr_regs->freq == freq) {
1735 		dev_dbg(dev, "%s: using curr_regs - %u Hz", __func__, freq);
1736 		return emif->curr_regs;
1737 	}
1738 
1739 	if (emif->duplicate)
1740 		regs_cache = emif1->regs_cache;
1741 	else
1742 		regs_cache = emif->regs_cache;
1743 
1744 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
1745 		if (regs_cache[i]->freq == freq) {
1746 			regs = regs_cache[i];
1747 			dev_dbg(dev,
1748 				"%s: reg dump found in reg cache for %u Hz\n",
1749 				__func__, freq);
1750 			break;
1751 		}
1752 	}
1753 
1754 	/*
1755 	 * If we don't have an entry for this frequency in the cache create one
1756 	 * and calculate the values
1757 	 */
1758 	if (!regs) {
1759 		regs = devm_kzalloc(emif->dev, sizeof(*regs), GFP_ATOMIC);
1760 		if (!regs)
1761 			return NULL;
1762 
1763 		if (get_emif_reg_values(emif, freq, regs)) {
1764 			devm_kfree(emif->dev, regs);
1765 			return NULL;
1766 		}
1767 
1768 		/*
1769 		 * Now look for an un-used entry in the cache and save the
1770 		 * newly created struct. If there are no free entries
1771 		 * over-write the last entry
1772 		 */
1773 		for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++)
1774 			;
1775 
1776 		if (i >= EMIF_MAX_NUM_FREQUENCIES) {
1777 			dev_warn(dev, "%s: regs_cache full - reusing a slot!!\n",
1778 				__func__);
1779 			i = EMIF_MAX_NUM_FREQUENCIES - 1;
1780 			devm_kfree(emif->dev, regs_cache[i]);
1781 		}
1782 		regs_cache[i] = regs;
1783 	}
1784 
1785 	return regs;
1786 }
1787 
1788 static void do_volt_notify_handling(struct emif_data *emif, u32 volt_state)
1789 {
1790 	dev_dbg(emif->dev, "%s: voltage notification : %d", __func__,
1791 		volt_state);
1792 
1793 	if (!emif->curr_regs) {
1794 		dev_err(emif->dev,
1795 			"%s: volt-notify before registers are ready: %d\n",
1796 			__func__, volt_state);
1797 		return;
1798 	}
1799 
1800 	setup_volt_sensitive_regs(emif, emif->curr_regs, volt_state);
1801 }
1802 
1803 /*
1804  * TODO: voltage notify handling should be hooked up to
1805  * regulator framework as soon as the necessary support
1806  * is available in mainline kernel. This function is un-used
1807  * right now.
1808  */
1809 static void __attribute__((unused)) volt_notify_handling(u32 volt_state)
1810 {
1811 	struct emif_data *emif;
1812 
1813 	spin_lock_irqsave(&emif_lock, irq_state);
1814 
1815 	list_for_each_entry(emif, &device_list, node)
1816 		do_volt_notify_handling(emif, volt_state);
1817 	do_freq_update();
1818 
1819 	spin_unlock_irqrestore(&emif_lock, irq_state);
1820 }
1821 
1822 static void do_freq_pre_notify_handling(struct emif_data *emif, u32 new_freq)
1823 {
1824 	struct emif_regs *regs;
1825 
1826 	regs = get_regs(emif, new_freq);
1827 	if (!regs)
1828 		return;
1829 
1830 	emif->curr_regs = regs;
1831 
1832 	/*
1833 	 * Update the shadow registers:
1834 	 * Temperature and voltage-ramp sensitive settings are also configured
1835 	 * in terms of DDR cycles. So, we need to update them too when there
1836 	 * is a freq change
1837 	 */
1838 	dev_dbg(emif->dev, "%s: setting up shadow registers for %uHz",
1839 		__func__, new_freq);
1840 	setup_registers(emif, regs);
1841 	setup_temperature_sensitive_regs(emif, regs);
1842 	setup_volt_sensitive_regs(emif, regs, DDR_VOLTAGE_STABLE);
1843 
1844 	/*
1845 	 * Part of workaround for errata i728. See do_freq_update()
1846 	 * for more details
1847 	 */
1848 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1849 		set_lpmode(emif, EMIF_LP_MODE_DISABLE);
1850 }
1851 
1852 /*
1853  * TODO: frequency notify handling should be hooked up to
1854  * clock framework as soon as the necessary support is
1855  * available in mainline kernel. This function is un-used
1856  * right now.
1857  */
1858 static void __attribute__((unused)) freq_pre_notify_handling(u32 new_freq)
1859 {
1860 	struct emif_data *emif;
1861 
1862 	/*
1863 	 * NOTE: we are taking the spin-lock here and releases it
1864 	 * only in post-notifier. This doesn't look good and
1865 	 * Sparse complains about it, but this seems to be
1866 	 * un-avoidable. We need to lock a sequence of events
1867 	 * that is split between EMIF and clock framework.
1868 	 *
1869 	 * 1. EMIF driver updates EMIF timings in shadow registers in the
1870 	 *    frequency pre-notify callback from clock framework
1871 	 * 2. clock framework sets up the registers for the new frequency
1872 	 * 3. clock framework initiates a hw-sequence that updates
1873 	 *    the frequency EMIF timings synchronously.
1874 	 *
1875 	 * All these 3 steps should be performed as an atomic operation
1876 	 * vis-a-vis similar sequence in the EMIF interrupt handler
1877 	 * for temperature events. Otherwise, there could be race
1878 	 * conditions that could result in incorrect EMIF timings for
1879 	 * a given frequency
1880 	 */
1881 	spin_lock_irqsave(&emif_lock, irq_state);
1882 
1883 	list_for_each_entry(emif, &device_list, node)
1884 		do_freq_pre_notify_handling(emif, new_freq);
1885 }
1886 
1887 static void do_freq_post_notify_handling(struct emif_data *emif)
1888 {
1889 	/*
1890 	 * Part of workaround for errata i728. See do_freq_update()
1891 	 * for more details
1892 	 */
1893 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1894 		set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
1895 }
1896 
1897 /*
1898  * TODO: frequency notify handling should be hooked up to
1899  * clock framework as soon as the necessary support is
1900  * available in mainline kernel. This function is un-used
1901  * right now.
1902  */
1903 static void __attribute__((unused)) freq_post_notify_handling(void)
1904 {
1905 	struct emif_data *emif;
1906 
1907 	list_for_each_entry(emif, &device_list, node)
1908 		do_freq_post_notify_handling(emif);
1909 
1910 	/*
1911 	 * Lock is done in pre-notify handler. See freq_pre_notify_handling()
1912 	 * for more details
1913 	 */
1914 	spin_unlock_irqrestore(&emif_lock, irq_state);
1915 }
1916 
1917 #if defined(CONFIG_OF)
1918 static const struct of_device_id emif_of_match[] = {
1919 		{ .compatible = "ti,emif-4d" },
1920 		{ .compatible = "ti,emif-4d5" },
1921 		{},
1922 };
1923 MODULE_DEVICE_TABLE(of, emif_of_match);
1924 #endif
1925 
1926 static struct platform_driver emif_driver = {
1927 	.remove		= __exit_p(emif_remove),
1928 	.shutdown	= emif_shutdown,
1929 	.driver = {
1930 		.name = "emif",
1931 		.of_match_table = of_match_ptr(emif_of_match),
1932 	},
1933 };
1934 
1935 module_platform_driver_probe(emif_driver, emif_probe);
1936 
1937 MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
1938 MODULE_LICENSE("GPL");
1939 MODULE_ALIAS("platform:emif");
1940 MODULE_AUTHOR("Texas Instruments Inc");
1941