xref: /openbmc/linux/drivers/memory/emif.c (revision e15a5365)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * EMIF driver
4  *
5  * Copyright (C) 2012 Texas Instruments, Inc.
6  *
7  * Aneesh V <aneesh@ti.com>
8  * Santosh Shilimkar <santosh.shilimkar@ti.com>
9  */
10 #include <linux/err.h>
11 #include <linux/kernel.h>
12 #include <linux/reboot.h>
13 #include <linux/platform_data/emif_plat.h>
14 #include <linux/io.h>
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
17 #include <linux/interrupt.h>
18 #include <linux/slab.h>
19 #include <linux/of.h>
20 #include <linux/debugfs.h>
21 #include <linux/seq_file.h>
22 #include <linux/module.h>
23 #include <linux/list.h>
24 #include <linux/spinlock.h>
25 #include <linux/pm.h>
26 
27 #include "emif.h"
28 #include "jedec_ddr.h"
29 #include "of_memory.h"
30 
31 /**
32  * struct emif_data - Per device static data for driver's use
33  * @duplicate:			Whether the DDR devices attached to this EMIF
34  *				instance are exactly same as that on EMIF1. In
35  *				this case we can save some memory and processing
36  * @temperature_level:		Maximum temperature of LPDDR2 devices attached
37  *				to this EMIF - read from MR4 register. If there
38  *				are two devices attached to this EMIF, this
39  *				value is the maximum of the two temperature
40  *				levels.
41  * @node:			node in the device list
42  * @base:			base address of memory-mapped IO registers.
43  * @dev:			device pointer.
44  * @addressing			table with addressing information from the spec
45  * @regs_cache:			An array of 'struct emif_regs' that stores
46  *				calculated register values for different
47  *				frequencies, to avoid re-calculating them on
48  *				each DVFS transition.
49  * @curr_regs:			The set of register values used in the last
50  *				frequency change (i.e. corresponding to the
51  *				frequency in effect at the moment)
52  * @plat_data:			Pointer to saved platform data.
53  * @debugfs_root:		dentry to the root folder for EMIF in debugfs
54  * @np_ddr:			Pointer to ddr device tree node
55  */
56 struct emif_data {
57 	u8				duplicate;
58 	u8				temperature_level;
59 	u8				lpmode;
60 	struct list_head		node;
61 	unsigned long			irq_state;
62 	void __iomem			*base;
63 	struct device			*dev;
64 	const struct lpddr2_addressing	*addressing;
65 	struct emif_regs		*regs_cache[EMIF_MAX_NUM_FREQUENCIES];
66 	struct emif_regs		*curr_regs;
67 	struct emif_platform_data	*plat_data;
68 	struct dentry			*debugfs_root;
69 	struct device_node		*np_ddr;
70 };
71 
72 static struct emif_data *emif1;
73 static spinlock_t	emif_lock;
74 static unsigned long	irq_state;
75 static u32		t_ck; /* DDR clock period in ps */
76 static LIST_HEAD(device_list);
77 
78 #ifdef CONFIG_DEBUG_FS
79 static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
80 	struct emif_regs *regs)
81 {
82 	u32 type = emif->plat_data->device_info->type;
83 	u32 ip_rev = emif->plat_data->ip_rev;
84 
85 	seq_printf(s, "EMIF register cache dump for %dMHz\n",
86 		regs->freq/1000000);
87 
88 	seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
89 	seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
90 	seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
91 	seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
92 
93 	if (ip_rev == EMIF_4D) {
94 		seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
95 			regs->read_idle_ctrl_shdw_normal);
96 		seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
97 			regs->read_idle_ctrl_shdw_volt_ramp);
98 	} else if (ip_rev == EMIF_4D5) {
99 		seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
100 			regs->dll_calib_ctrl_shdw_normal);
101 		seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
102 			regs->dll_calib_ctrl_shdw_volt_ramp);
103 	}
104 
105 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
106 		seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
107 			regs->ref_ctrl_shdw_derated);
108 		seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
109 			regs->sdram_tim1_shdw_derated);
110 		seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
111 			regs->sdram_tim3_shdw_derated);
112 	}
113 }
114 
115 static int emif_regdump_show(struct seq_file *s, void *unused)
116 {
117 	struct emif_data	*emif	= s->private;
118 	struct emif_regs	**regs_cache;
119 	int			i;
120 
121 	if (emif->duplicate)
122 		regs_cache = emif1->regs_cache;
123 	else
124 		regs_cache = emif->regs_cache;
125 
126 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
127 		do_emif_regdump_show(s, emif, regs_cache[i]);
128 		seq_putc(s, '\n');
129 	}
130 
131 	return 0;
132 }
133 
134 DEFINE_SHOW_ATTRIBUTE(emif_regdump);
135 
136 static int emif_mr4_show(struct seq_file *s, void *unused)
137 {
138 	struct emif_data *emif = s->private;
139 
140 	seq_printf(s, "MR4=%d\n", emif->temperature_level);
141 	return 0;
142 }
143 
144 DEFINE_SHOW_ATTRIBUTE(emif_mr4);
145 
146 static int __init_or_module emif_debugfs_init(struct emif_data *emif)
147 {
148 	emif->debugfs_root = debugfs_create_dir(dev_name(emif->dev), NULL);
149 	debugfs_create_file("regcache_dump", S_IRUGO, emif->debugfs_root, emif,
150 			    &emif_regdump_fops);
151 	debugfs_create_file("mr4", S_IRUGO, emif->debugfs_root, emif,
152 			    &emif_mr4_fops);
153 	return 0;
154 }
155 
156 static void __exit emif_debugfs_exit(struct emif_data *emif)
157 {
158 	debugfs_remove_recursive(emif->debugfs_root);
159 	emif->debugfs_root = NULL;
160 }
161 #else
162 static inline int __init_or_module emif_debugfs_init(struct emif_data *emif)
163 {
164 	return 0;
165 }
166 
167 static inline void __exit emif_debugfs_exit(struct emif_data *emif)
168 {
169 }
170 #endif
171 
172 /*
173  * Calculate the period of DDR clock from frequency value
174  */
175 static void set_ddr_clk_period(u32 freq)
176 {
177 	/* Divide 10^12 by frequency to get period in ps */
178 	t_ck = (u32)DIV_ROUND_UP_ULL(1000000000000ull, freq);
179 }
180 
181 /*
182  * Get bus width used by EMIF. Note that this may be different from the
183  * bus width of the DDR devices used. For instance two 16-bit DDR devices
184  * may be connected to a given CS of EMIF. In this case bus width as far
185  * as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
186  */
187 static u32 get_emif_bus_width(struct emif_data *emif)
188 {
189 	u32		width;
190 	void __iomem	*base = emif->base;
191 
192 	width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
193 			>> NARROW_MODE_SHIFT;
194 	width = width == 0 ? 32 : 16;
195 
196 	return width;
197 }
198 
199 /*
200  * Get the CL from SDRAM_CONFIG register
201  */
202 static u32 get_cl(struct emif_data *emif)
203 {
204 	u32		cl;
205 	void __iomem	*base = emif->base;
206 
207 	cl = (readl(base + EMIF_SDRAM_CONFIG) & CL_MASK) >> CL_SHIFT;
208 
209 	return cl;
210 }
211 
212 static void set_lpmode(struct emif_data *emif, u8 lpmode)
213 {
214 	u32 temp;
215 	void __iomem *base = emif->base;
216 
217 	/*
218 	 * Workaround for errata i743 - LPDDR2 Power-Down State is Not
219 	 * Efficient
220 	 *
221 	 * i743 DESCRIPTION:
222 	 * The EMIF supports power-down state for low power. The EMIF
223 	 * automatically puts the SDRAM into power-down after the memory is
224 	 * not accessed for a defined number of cycles and the
225 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set to 0x4.
226 	 * As the EMIF supports automatic output impedance calibration, a ZQ
227 	 * calibration long command is issued every time it exits active
228 	 * power-down and precharge power-down modes. The EMIF waits and
229 	 * blocks any other command during this calibration.
230 	 * The EMIF does not allow selective disabling of ZQ calibration upon
231 	 * exit of power-down mode. Due to very short periods of power-down
232 	 * cycles, ZQ calibration overhead creates bandwidth issues and
233 	 * increases overall system power consumption. On the other hand,
234 	 * issuing ZQ calibration long commands when exiting self-refresh is
235 	 * still required.
236 	 *
237 	 * WORKAROUND
238 	 * Because there is no power consumption benefit of the power-down due
239 	 * to the calibration and there is a performance risk, the guideline
240 	 * is to not allow power-down state and, therefore, to not have set
241 	 * the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field to 0x4.
242 	 */
243 	if ((emif->plat_data->ip_rev == EMIF_4D) &&
244 	    (lpmode == EMIF_LP_MODE_PWR_DN)) {
245 		WARN_ONCE(1,
246 			  "REG_LP_MODE = LP_MODE_PWR_DN(4) is prohibited by erratum i743 switch to LP_MODE_SELF_REFRESH(2)\n");
247 		/* rollback LP_MODE to Self-refresh mode */
248 		lpmode = EMIF_LP_MODE_SELF_REFRESH;
249 	}
250 
251 	temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
252 	temp &= ~LP_MODE_MASK;
253 	temp |= (lpmode << LP_MODE_SHIFT);
254 	writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
255 }
256 
257 static void do_freq_update(void)
258 {
259 	struct emif_data *emif;
260 
261 	/*
262 	 * Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
263 	 *
264 	 * i728 DESCRIPTION:
265 	 * The EMIF automatically puts the SDRAM into self-refresh mode
266 	 * after the EMIF has not performed accesses during
267 	 * EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
268 	 * and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
269 	 * to 0x2. If during a small window the following three events
270 	 * occur:
271 	 * - The SR_TIMING counter expires
272 	 * - And frequency change is requested
273 	 * - And OCP access is requested
274 	 * Then it causes instable clock on the DDR interface.
275 	 *
276 	 * WORKAROUND
277 	 * To avoid the occurrence of the three events, the workaround
278 	 * is to disable the self-refresh when requesting a frequency
279 	 * change. Before requesting a frequency change the software must
280 	 * program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
281 	 * frequency change has been done, the software can reprogram
282 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
283 	 */
284 	list_for_each_entry(emif, &device_list, node) {
285 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
286 			set_lpmode(emif, EMIF_LP_MODE_DISABLE);
287 	}
288 
289 	/*
290 	 * TODO: Do FREQ_UPDATE here when an API
291 	 * is available for this as part of the new
292 	 * clock framework
293 	 */
294 
295 	list_for_each_entry(emif, &device_list, node) {
296 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
297 			set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
298 	}
299 }
300 
301 /* Find addressing table entry based on the device's type and density */
302 static const struct lpddr2_addressing *get_addressing_table(
303 	const struct ddr_device_info *device_info)
304 {
305 	u32		index, type, density;
306 
307 	type = device_info->type;
308 	density = device_info->density;
309 
310 	switch (type) {
311 	case DDR_TYPE_LPDDR2_S4:
312 		index = density - 1;
313 		break;
314 	case DDR_TYPE_LPDDR2_S2:
315 		switch (density) {
316 		case DDR_DENSITY_1Gb:
317 		case DDR_DENSITY_2Gb:
318 			index = density + 3;
319 			break;
320 		default:
321 			index = density - 1;
322 		}
323 		break;
324 	default:
325 		return NULL;
326 	}
327 
328 	return &lpddr2_jedec_addressing_table[index];
329 }
330 
331 /*
332  * Find the the right timing table from the array of timing
333  * tables of the device using DDR clock frequency
334  */
335 static const struct lpddr2_timings *get_timings_table(struct emif_data *emif,
336 		u32 freq)
337 {
338 	u32				i, min, max, freq_nearest;
339 	const struct lpddr2_timings	*timings = NULL;
340 	const struct lpddr2_timings	*timings_arr = emif->plat_data->timings;
341 	struct				device *dev = emif->dev;
342 
343 	/* Start with a very high frequency - 1GHz */
344 	freq_nearest = 1000000000;
345 
346 	/*
347 	 * Find the timings table such that:
348 	 *  1. the frequency range covers the required frequency(safe) AND
349 	 *  2. the max_freq is closest to the required frequency(optimal)
350 	 */
351 	for (i = 0; i < emif->plat_data->timings_arr_size; i++) {
352 		max = timings_arr[i].max_freq;
353 		min = timings_arr[i].min_freq;
354 		if ((freq >= min) && (freq <= max) && (max < freq_nearest)) {
355 			freq_nearest = max;
356 			timings = &timings_arr[i];
357 		}
358 	}
359 
360 	if (!timings)
361 		dev_err(dev, "%s: couldn't find timings for - %dHz\n",
362 			__func__, freq);
363 
364 	dev_dbg(dev, "%s: timings table: freq %d, speed bin freq %d\n",
365 		__func__, freq, freq_nearest);
366 
367 	return timings;
368 }
369 
370 static u32 get_sdram_ref_ctrl_shdw(u32 freq,
371 		const struct lpddr2_addressing *addressing)
372 {
373 	u32 ref_ctrl_shdw = 0, val = 0, freq_khz, t_refi;
374 
375 	/* Scale down frequency and t_refi to avoid overflow */
376 	freq_khz = freq / 1000;
377 	t_refi = addressing->tREFI_ns / 100;
378 
379 	/*
380 	 * refresh rate to be set is 'tREFI(in us) * freq in MHz
381 	 * division by 10000 to account for change in units
382 	 */
383 	val = t_refi * freq_khz / 10000;
384 	ref_ctrl_shdw |= val << REFRESH_RATE_SHIFT;
385 
386 	return ref_ctrl_shdw;
387 }
388 
389 static u32 get_sdram_tim_1_shdw(const struct lpddr2_timings *timings,
390 		const struct lpddr2_min_tck *min_tck,
391 		const struct lpddr2_addressing *addressing)
392 {
393 	u32 tim1 = 0, val = 0;
394 
395 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
396 	tim1 |= val << T_WTR_SHIFT;
397 
398 	if (addressing->num_banks == B8)
399 		val = DIV_ROUND_UP(timings->tFAW, t_ck*4);
400 	else
401 		val = max(min_tck->tRRD, DIV_ROUND_UP(timings->tRRD, t_ck));
402 	tim1 |= (val - 1) << T_RRD_SHIFT;
403 
404 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab, t_ck) - 1;
405 	tim1 |= val << T_RC_SHIFT;
406 
407 	val = max(min_tck->tRASmin, DIV_ROUND_UP(timings->tRAS_min, t_ck));
408 	tim1 |= (val - 1) << T_RAS_SHIFT;
409 
410 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
411 	tim1 |= val << T_WR_SHIFT;
412 
413 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD, t_ck)) - 1;
414 	tim1 |= val << T_RCD_SHIFT;
415 
416 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab, t_ck)) - 1;
417 	tim1 |= val << T_RP_SHIFT;
418 
419 	return tim1;
420 }
421 
422 static u32 get_sdram_tim_1_shdw_derated(const struct lpddr2_timings *timings,
423 		const struct lpddr2_min_tck *min_tck,
424 		const struct lpddr2_addressing *addressing)
425 {
426 	u32 tim1 = 0, val = 0;
427 
428 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
429 	tim1 = val << T_WTR_SHIFT;
430 
431 	/*
432 	 * tFAW is approximately 4 times tRRD. So add 1875*4 = 7500ps
433 	 * to tFAW for de-rating
434 	 */
435 	if (addressing->num_banks == B8) {
436 		val = DIV_ROUND_UP(timings->tFAW + 7500, 4 * t_ck) - 1;
437 	} else {
438 		val = DIV_ROUND_UP(timings->tRRD + 1875, t_ck);
439 		val = max(min_tck->tRRD, val) - 1;
440 	}
441 	tim1 |= val << T_RRD_SHIFT;
442 
443 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab + 1875, t_ck);
444 	tim1 |= (val - 1) << T_RC_SHIFT;
445 
446 	val = DIV_ROUND_UP(timings->tRAS_min + 1875, t_ck);
447 	val = max(min_tck->tRASmin, val) - 1;
448 	tim1 |= val << T_RAS_SHIFT;
449 
450 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
451 	tim1 |= val << T_WR_SHIFT;
452 
453 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD + 1875, t_ck));
454 	tim1 |= (val - 1) << T_RCD_SHIFT;
455 
456 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab + 1875, t_ck));
457 	tim1 |= (val - 1) << T_RP_SHIFT;
458 
459 	return tim1;
460 }
461 
462 static u32 get_sdram_tim_2_shdw(const struct lpddr2_timings *timings,
463 		const struct lpddr2_min_tck *min_tck,
464 		const struct lpddr2_addressing *addressing,
465 		u32 type)
466 {
467 	u32 tim2 = 0, val = 0;
468 
469 	val = min_tck->tCKE - 1;
470 	tim2 |= val << T_CKE_SHIFT;
471 
472 	val = max(min_tck->tRTP, DIV_ROUND_UP(timings->tRTP, t_ck)) - 1;
473 	tim2 |= val << T_RTP_SHIFT;
474 
475 	/* tXSNR = tRFCab_ps + 10 ns(tRFCab_ps for LPDDR2). */
476 	val = DIV_ROUND_UP(addressing->tRFCab_ps + 10000, t_ck) - 1;
477 	tim2 |= val << T_XSNR_SHIFT;
478 
479 	/* XSRD same as XSNR for LPDDR2 */
480 	tim2 |= val << T_XSRD_SHIFT;
481 
482 	val = max(min_tck->tXP, DIV_ROUND_UP(timings->tXP, t_ck)) - 1;
483 	tim2 |= val << T_XP_SHIFT;
484 
485 	return tim2;
486 }
487 
488 static u32 get_sdram_tim_3_shdw(const struct lpddr2_timings *timings,
489 		const struct lpddr2_min_tck *min_tck,
490 		const struct lpddr2_addressing *addressing,
491 		u32 type, u32 ip_rev, u32 derated)
492 {
493 	u32 tim3 = 0, val = 0, t_dqsck;
494 
495 	val = timings->tRAS_max_ns / addressing->tREFI_ns - 1;
496 	val = val > 0xF ? 0xF : val;
497 	tim3 |= val << T_RAS_MAX_SHIFT;
498 
499 	val = DIV_ROUND_UP(addressing->tRFCab_ps, t_ck) - 1;
500 	tim3 |= val << T_RFC_SHIFT;
501 
502 	t_dqsck = (derated == EMIF_DERATED_TIMINGS) ?
503 		timings->tDQSCK_max_derated : timings->tDQSCK_max;
504 	if (ip_rev == EMIF_4D5)
505 		val = DIV_ROUND_UP(t_dqsck + 1000, t_ck) - 1;
506 	else
507 		val = DIV_ROUND_UP(t_dqsck, t_ck) - 1;
508 
509 	tim3 |= val << T_TDQSCKMAX_SHIFT;
510 
511 	val = DIV_ROUND_UP(timings->tZQCS, t_ck) - 1;
512 	tim3 |= val << ZQ_ZQCS_SHIFT;
513 
514 	val = DIV_ROUND_UP(timings->tCKESR, t_ck);
515 	val = max(min_tck->tCKESR, val) - 1;
516 	tim3 |= val << T_CKESR_SHIFT;
517 
518 	if (ip_rev == EMIF_4D5) {
519 		tim3 |= (EMIF_T_CSTA - 1) << T_CSTA_SHIFT;
520 
521 		val = DIV_ROUND_UP(EMIF_T_PDLL_UL, 128) - 1;
522 		tim3 |= val << T_PDLL_UL_SHIFT;
523 	}
524 
525 	return tim3;
526 }
527 
528 static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
529 		bool cs1_used, bool cal_resistors_per_cs)
530 {
531 	u32 zq = 0, val = 0;
532 
533 	val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
534 	zq |= val << ZQ_REFINTERVAL_SHIFT;
535 
536 	val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
537 	zq |= val << ZQ_ZQCL_MULT_SHIFT;
538 
539 	val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
540 	zq |= val << ZQ_ZQINIT_MULT_SHIFT;
541 
542 	zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
543 
544 	if (cal_resistors_per_cs)
545 		zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
546 	else
547 		zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
548 
549 	zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
550 
551 	val = cs1_used ? 1 : 0;
552 	zq |= val << ZQ_CS1EN_SHIFT;
553 
554 	return zq;
555 }
556 
557 static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
558 		const struct emif_custom_configs *custom_configs, bool cs1_used,
559 		u32 sdram_io_width, u32 emif_bus_width)
560 {
561 	u32 alert = 0, interval, devcnt;
562 
563 	if (custom_configs && (custom_configs->mask &
564 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
565 		interval = custom_configs->temp_alert_poll_interval_ms;
566 	else
567 		interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
568 
569 	interval *= 1000000;			/* Convert to ns */
570 	interval /= addressing->tREFI_ns;	/* Convert to refresh cycles */
571 	alert |= (interval << TA_REFINTERVAL_SHIFT);
572 
573 	/*
574 	 * sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
575 	 * also to this form and subtract to get TA_DEVCNT, which is
576 	 * in log2(x) form.
577 	 */
578 	emif_bus_width = __fls(emif_bus_width) - 1;
579 	devcnt = emif_bus_width - sdram_io_width;
580 	alert |= devcnt << TA_DEVCNT_SHIFT;
581 
582 	/* DEVWDT is in 'log2(x) - 3' form */
583 	alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
584 
585 	alert |= 1 << TA_SFEXITEN_SHIFT;
586 	alert |= 1 << TA_CS0EN_SHIFT;
587 	alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
588 
589 	return alert;
590 }
591 
592 static u32 get_read_idle_ctrl_shdw(u8 volt_ramp)
593 {
594 	u32 idle = 0, val = 0;
595 
596 	/*
597 	 * Maximum value in normal conditions and increased frequency
598 	 * when voltage is ramping
599 	 */
600 	if (volt_ramp)
601 		val = READ_IDLE_INTERVAL_DVFS / t_ck / 64 - 1;
602 	else
603 		val = 0x1FF;
604 
605 	/*
606 	 * READ_IDLE_CTRL register in EMIF4D has same offset and fields
607 	 * as DLL_CALIB_CTRL in EMIF4D5, so use the same shifts
608 	 */
609 	idle |= val << DLL_CALIB_INTERVAL_SHIFT;
610 	idle |= EMIF_READ_IDLE_LEN_VAL << ACK_WAIT_SHIFT;
611 
612 	return idle;
613 }
614 
615 static u32 get_dll_calib_ctrl_shdw(u8 volt_ramp)
616 {
617 	u32 calib = 0, val = 0;
618 
619 	if (volt_ramp == DDR_VOLTAGE_RAMPING)
620 		val = DLL_CALIB_INTERVAL_DVFS / t_ck / 16 - 1;
621 	else
622 		val = 0; /* Disabled when voltage is stable */
623 
624 	calib |= val << DLL_CALIB_INTERVAL_SHIFT;
625 	calib |= DLL_CALIB_ACK_WAIT_VAL << ACK_WAIT_SHIFT;
626 
627 	return calib;
628 }
629 
630 static u32 get_ddr_phy_ctrl_1_attilaphy_4d(const struct lpddr2_timings *timings,
631 	u32 freq, u8 RL)
632 {
633 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_ATTILAPHY, val = 0;
634 
635 	val = RL + DIV_ROUND_UP(timings->tDQSCK_max, t_ck) - 1;
636 	phy |= val << READ_LATENCY_SHIFT_4D;
637 
638 	if (freq <= 100000000)
639 		val = EMIF_DLL_SLAVE_DLY_CTRL_100_MHZ_AND_LESS_ATTILAPHY;
640 	else if (freq <= 200000000)
641 		val = EMIF_DLL_SLAVE_DLY_CTRL_200_MHZ_ATTILAPHY;
642 	else
643 		val = EMIF_DLL_SLAVE_DLY_CTRL_400_MHZ_ATTILAPHY;
644 
645 	phy |= val << DLL_SLAVE_DLY_CTRL_SHIFT_4D;
646 
647 	return phy;
648 }
649 
650 static u32 get_phy_ctrl_1_intelliphy_4d5(u32 freq, u8 cl)
651 {
652 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_INTELLIPHY, half_delay;
653 
654 	/*
655 	 * DLL operates at 266 MHz. If DDR frequency is near 266 MHz,
656 	 * half-delay is not needed else set half-delay
657 	 */
658 	if (freq >= 265000000 && freq < 267000000)
659 		half_delay = 0;
660 	else
661 		half_delay = 1;
662 
663 	phy |= half_delay << DLL_HALF_DELAY_SHIFT_4D5;
664 	phy |= ((cl + DIV_ROUND_UP(EMIF_PHY_TOTAL_READ_LATENCY_INTELLIPHY_PS,
665 			t_ck) - 1) << READ_LATENCY_SHIFT_4D5);
666 
667 	return phy;
668 }
669 
670 static u32 get_ext_phy_ctrl_2_intelliphy_4d5(void)
671 {
672 	u32 fifo_we_slave_ratio;
673 
674 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
675 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256, t_ck);
676 
677 	return fifo_we_slave_ratio | fifo_we_slave_ratio << 11 |
678 		fifo_we_slave_ratio << 22;
679 }
680 
681 static u32 get_ext_phy_ctrl_3_intelliphy_4d5(void)
682 {
683 	u32 fifo_we_slave_ratio;
684 
685 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
686 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256, t_ck);
687 
688 	return fifo_we_slave_ratio >> 10 | fifo_we_slave_ratio << 1 |
689 		fifo_we_slave_ratio << 12 | fifo_we_slave_ratio << 23;
690 }
691 
692 static u32 get_ext_phy_ctrl_4_intelliphy_4d5(void)
693 {
694 	u32 fifo_we_slave_ratio;
695 
696 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
697 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256, t_ck);
698 
699 	return fifo_we_slave_ratio >> 9 | fifo_we_slave_ratio << 2 |
700 		fifo_we_slave_ratio << 13;
701 }
702 
703 static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
704 {
705 	u32 pwr_mgmt_ctrl	= 0, timeout;
706 	u32 lpmode		= EMIF_LP_MODE_SELF_REFRESH;
707 	u32 timeout_perf	= EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
708 	u32 timeout_pwr		= EMIF_LP_MODE_TIMEOUT_POWER;
709 	u32 freq_threshold	= EMIF_LP_MODE_FREQ_THRESHOLD;
710 	u32 mask;
711 	u8 shift;
712 
713 	struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
714 
715 	if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
716 		lpmode		= cust_cfgs->lpmode;
717 		timeout_perf	= cust_cfgs->lpmode_timeout_performance;
718 		timeout_pwr	= cust_cfgs->lpmode_timeout_power;
719 		freq_threshold  = cust_cfgs->lpmode_freq_threshold;
720 	}
721 
722 	/* Timeout based on DDR frequency */
723 	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
724 
725 	/*
726 	 * The value to be set in register is "log2(timeout) - 3"
727 	 * if timeout < 16 load 0 in register
728 	 * if timeout is not a power of 2, round to next highest power of 2
729 	 */
730 	if (timeout < 16) {
731 		timeout = 0;
732 	} else {
733 		if (timeout & (timeout - 1))
734 			timeout <<= 1;
735 		timeout = __fls(timeout) - 3;
736 	}
737 
738 	switch (lpmode) {
739 	case EMIF_LP_MODE_CLOCK_STOP:
740 		shift = CS_TIM_SHIFT;
741 		mask = CS_TIM_MASK;
742 		break;
743 	case EMIF_LP_MODE_SELF_REFRESH:
744 		/* Workaround for errata i735 */
745 		if (timeout < 6)
746 			timeout = 6;
747 
748 		shift = SR_TIM_SHIFT;
749 		mask = SR_TIM_MASK;
750 		break;
751 	case EMIF_LP_MODE_PWR_DN:
752 		shift = PD_TIM_SHIFT;
753 		mask = PD_TIM_MASK;
754 		break;
755 	case EMIF_LP_MODE_DISABLE:
756 	default:
757 		mask = 0;
758 		shift = 0;
759 		break;
760 	}
761 	/* Round to maximum in case of overflow, BUT warn! */
762 	if (lpmode != EMIF_LP_MODE_DISABLE && timeout > mask >> shift) {
763 		pr_err("TIMEOUT Overflow - lpmode=%d perf=%d pwr=%d freq=%d\n",
764 		       lpmode,
765 		       timeout_perf,
766 		       timeout_pwr,
767 		       freq_threshold);
768 		WARN(1, "timeout=0x%02x greater than 0x%02x. Using max\n",
769 		     timeout, mask >> shift);
770 		timeout = mask >> shift;
771 	}
772 
773 	/* Setup required timing */
774 	pwr_mgmt_ctrl = (timeout << shift) & mask;
775 	/* setup a default mask for rest of the modes */
776 	pwr_mgmt_ctrl |= (SR_TIM_MASK | CS_TIM_MASK | PD_TIM_MASK) &
777 			  ~mask;
778 
779 	/* No CS_TIM in EMIF_4D5 */
780 	if (ip_rev == EMIF_4D5)
781 		pwr_mgmt_ctrl &= ~CS_TIM_MASK;
782 
783 	pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
784 
785 	return pwr_mgmt_ctrl;
786 }
787 
788 /*
789  * Get the temperature level of the EMIF instance:
790  * Reads the MR4 register of attached SDRAM parts to find out the temperature
791  * level. If there are two parts attached(one on each CS), then the temperature
792  * level for the EMIF instance is the higher of the two temperatures.
793  */
794 static void get_temperature_level(struct emif_data *emif)
795 {
796 	u32		temp, temperature_level;
797 	void __iomem	*base;
798 
799 	base = emif->base;
800 
801 	/* Read mode register 4 */
802 	writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
803 	temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
804 	temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
805 				MR4_SDRAM_REF_RATE_SHIFT;
806 
807 	if (emif->plat_data->device_info->cs1_used) {
808 		writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
809 		temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
810 		temp = (temp & MR4_SDRAM_REF_RATE_MASK)
811 				>> MR4_SDRAM_REF_RATE_SHIFT;
812 		temperature_level = max(temp, temperature_level);
813 	}
814 
815 	/* treat everything less than nominal(3) in MR4 as nominal */
816 	if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
817 		temperature_level = SDRAM_TEMP_NOMINAL;
818 
819 	/* if we get reserved value in MR4 persist with the existing value */
820 	if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
821 		emif->temperature_level = temperature_level;
822 }
823 
824 /*
825  * Program EMIF shadow registers that are not dependent on temperature
826  * or voltage
827  */
828 static void setup_registers(struct emif_data *emif, struct emif_regs *regs)
829 {
830 	void __iomem	*base = emif->base;
831 
832 	writel(regs->sdram_tim2_shdw, base + EMIF_SDRAM_TIMING_2_SHDW);
833 	writel(regs->phy_ctrl_1_shdw, base + EMIF_DDR_PHY_CTRL_1_SHDW);
834 	writel(regs->pwr_mgmt_ctrl_shdw,
835 	       base + EMIF_POWER_MANAGEMENT_CTRL_SHDW);
836 
837 	/* Settings specific for EMIF4D5 */
838 	if (emif->plat_data->ip_rev != EMIF_4D5)
839 		return;
840 	writel(regs->ext_phy_ctrl_2_shdw, base + EMIF_EXT_PHY_CTRL_2_SHDW);
841 	writel(regs->ext_phy_ctrl_3_shdw, base + EMIF_EXT_PHY_CTRL_3_SHDW);
842 	writel(regs->ext_phy_ctrl_4_shdw, base + EMIF_EXT_PHY_CTRL_4_SHDW);
843 }
844 
845 /*
846  * When voltage ramps dll calibration and forced read idle should
847  * happen more often
848  */
849 static void setup_volt_sensitive_regs(struct emif_data *emif,
850 		struct emif_regs *regs, u32 volt_state)
851 {
852 	u32		calib_ctrl;
853 	void __iomem	*base = emif->base;
854 
855 	/*
856 	 * EMIF_READ_IDLE_CTRL in EMIF4D refers to the same register as
857 	 * EMIF_DLL_CALIB_CTRL in EMIF4D5 and dll_calib_ctrl_shadow_*
858 	 * is an alias of the respective read_idle_ctrl_shdw_* (members of
859 	 * a union). So, the below code takes care of both cases
860 	 */
861 	if (volt_state == DDR_VOLTAGE_RAMPING)
862 		calib_ctrl = regs->dll_calib_ctrl_shdw_volt_ramp;
863 	else
864 		calib_ctrl = regs->dll_calib_ctrl_shdw_normal;
865 
866 	writel(calib_ctrl, base + EMIF_DLL_CALIB_CTRL_SHDW);
867 }
868 
869 /*
870  * setup_temperature_sensitive_regs() - set the timings for temperature
871  * sensitive registers. This happens once at initialisation time based
872  * on the temperature at boot time and subsequently based on the temperature
873  * alert interrupt. Temperature alert can happen when the temperature
874  * increases or drops. So this function can have the effect of either
875  * derating the timings or going back to nominal values.
876  */
877 static void setup_temperature_sensitive_regs(struct emif_data *emif,
878 		struct emif_regs *regs)
879 {
880 	u32		tim1, tim3, ref_ctrl, type;
881 	void __iomem	*base = emif->base;
882 	u32		temperature;
883 
884 	type = emif->plat_data->device_info->type;
885 
886 	tim1 = regs->sdram_tim1_shdw;
887 	tim3 = regs->sdram_tim3_shdw;
888 	ref_ctrl = regs->ref_ctrl_shdw;
889 
890 	/* No de-rating for non-lpddr2 devices */
891 	if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
892 		goto out;
893 
894 	temperature = emif->temperature_level;
895 	if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
896 		ref_ctrl = regs->ref_ctrl_shdw_derated;
897 	} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
898 		tim1 = regs->sdram_tim1_shdw_derated;
899 		tim3 = regs->sdram_tim3_shdw_derated;
900 		ref_ctrl = regs->ref_ctrl_shdw_derated;
901 	}
902 
903 out:
904 	writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
905 	writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
906 	writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
907 }
908 
909 static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
910 {
911 	u32		old_temp_level;
912 	irqreturn_t	ret = IRQ_HANDLED;
913 	struct emif_custom_configs *custom_configs;
914 
915 	spin_lock_irqsave(&emif_lock, irq_state);
916 	old_temp_level = emif->temperature_level;
917 	get_temperature_level(emif);
918 
919 	if (unlikely(emif->temperature_level == old_temp_level)) {
920 		goto out;
921 	} else if (!emif->curr_regs) {
922 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
923 		goto out;
924 	}
925 
926 	custom_configs = emif->plat_data->custom_configs;
927 
928 	/*
929 	 * IF we detect higher than "nominal rating" from DDR sensor
930 	 * on an unsupported DDR part, shutdown system
931 	 */
932 	if (custom_configs && !(custom_configs->mask &
933 				EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART)) {
934 		if (emif->temperature_level >= SDRAM_TEMP_HIGH_DERATE_REFRESH) {
935 			dev_err(emif->dev,
936 				"%s:NOT Extended temperature capable memory. Converting MR4=0x%02x as shutdown event\n",
937 				__func__, emif->temperature_level);
938 			/*
939 			 * Temperature far too high - do kernel_power_off()
940 			 * from thread context
941 			 */
942 			emif->temperature_level = SDRAM_TEMP_VERY_HIGH_SHUTDOWN;
943 			ret = IRQ_WAKE_THREAD;
944 			goto out;
945 		}
946 	}
947 
948 	if (emif->temperature_level < old_temp_level ||
949 		emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
950 		/*
951 		 * Temperature coming down - defer handling to thread OR
952 		 * Temperature far too high - do kernel_power_off() from
953 		 * thread context
954 		 */
955 		ret = IRQ_WAKE_THREAD;
956 	} else {
957 		/* Temperature is going up - handle immediately */
958 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
959 		do_freq_update();
960 	}
961 
962 out:
963 	spin_unlock_irqrestore(&emif_lock, irq_state);
964 	return ret;
965 }
966 
967 static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
968 {
969 	u32			interrupts;
970 	struct emif_data	*emif = dev_id;
971 	void __iomem		*base = emif->base;
972 	struct device		*dev = emif->dev;
973 	irqreturn_t		ret = IRQ_HANDLED;
974 
975 	/* Save the status and clear it */
976 	interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
977 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
978 
979 	/*
980 	 * Handle temperature alert
981 	 * Temperature alert should be same for all ports
982 	 * So, it's enough to process it only for one of the ports
983 	 */
984 	if (interrupts & TA_SYS_MASK)
985 		ret = handle_temp_alert(base, emif);
986 
987 	if (interrupts & ERR_SYS_MASK)
988 		dev_err(dev, "Access error from SYS port - %x\n", interrupts);
989 
990 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
991 		/* Save the status and clear it */
992 		interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
993 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
994 
995 		if (interrupts & ERR_LL_MASK)
996 			dev_err(dev, "Access error from LL port - %x\n",
997 				interrupts);
998 	}
999 
1000 	return ret;
1001 }
1002 
1003 static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
1004 {
1005 	struct emif_data	*emif = dev_id;
1006 
1007 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
1008 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1009 
1010 		/* If we have Power OFF ability, use it, else try restarting */
1011 		if (pm_power_off) {
1012 			kernel_power_off();
1013 		} else {
1014 			WARN(1, "FIXME: NO pm_power_off!!! trying restart\n");
1015 			kernel_restart("SDRAM Over-temp Emergency restart");
1016 		}
1017 		return IRQ_HANDLED;
1018 	}
1019 
1020 	spin_lock_irqsave(&emif_lock, irq_state);
1021 
1022 	if (emif->curr_regs) {
1023 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
1024 		do_freq_update();
1025 	} else {
1026 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
1027 	}
1028 
1029 	spin_unlock_irqrestore(&emif_lock, irq_state);
1030 
1031 	return IRQ_HANDLED;
1032 }
1033 
1034 static void clear_all_interrupts(struct emif_data *emif)
1035 {
1036 	void __iomem	*base = emif->base;
1037 
1038 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
1039 		base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1040 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1041 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
1042 			base + EMIF_LL_OCP_INTERRUPT_STATUS);
1043 }
1044 
1045 static void disable_and_clear_all_interrupts(struct emif_data *emif)
1046 {
1047 	void __iomem		*base = emif->base;
1048 
1049 	/* Disable all interrupts */
1050 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
1051 		base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
1052 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1053 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
1054 			base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
1055 
1056 	/* Clear all interrupts */
1057 	clear_all_interrupts(emif);
1058 }
1059 
1060 static int __init_or_module setup_interrupts(struct emif_data *emif, u32 irq)
1061 {
1062 	u32		interrupts, type;
1063 	void __iomem	*base = emif->base;
1064 
1065 	type = emif->plat_data->device_info->type;
1066 
1067 	clear_all_interrupts(emif);
1068 
1069 	/* Enable interrupts for SYS interface */
1070 	interrupts = EN_ERR_SYS_MASK;
1071 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
1072 		interrupts |= EN_TA_SYS_MASK;
1073 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
1074 
1075 	/* Enable interrupts for LL interface */
1076 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1077 		/* TA need not be enabled for LL */
1078 		interrupts = EN_ERR_LL_MASK;
1079 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
1080 	}
1081 
1082 	/* setup IRQ handlers */
1083 	return devm_request_threaded_irq(emif->dev, irq,
1084 				    emif_interrupt_handler,
1085 				    emif_threaded_isr,
1086 				    0, dev_name(emif->dev),
1087 				    emif);
1088 
1089 }
1090 
1091 static void __init_or_module emif_onetime_settings(struct emif_data *emif)
1092 {
1093 	u32				pwr_mgmt_ctrl, zq, temp_alert_cfg;
1094 	void __iomem			*base = emif->base;
1095 	const struct lpddr2_addressing	*addressing;
1096 	const struct ddr_device_info	*device_info;
1097 
1098 	device_info = emif->plat_data->device_info;
1099 	addressing = get_addressing_table(device_info);
1100 
1101 	/*
1102 	 * Init power management settings
1103 	 * We don't know the frequency yet. Use a high frequency
1104 	 * value for a conservative timeout setting
1105 	 */
1106 	pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
1107 			emif->plat_data->ip_rev);
1108 	emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
1109 	writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
1110 
1111 	/* Init ZQ calibration settings */
1112 	zq = get_zq_config_reg(addressing, device_info->cs1_used,
1113 		device_info->cal_resistors_per_cs);
1114 	writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
1115 
1116 	/* Check temperature level temperature level*/
1117 	get_temperature_level(emif);
1118 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
1119 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1120 
1121 	/* Init temperature polling */
1122 	temp_alert_cfg = get_temp_alert_config(addressing,
1123 		emif->plat_data->custom_configs, device_info->cs1_used,
1124 		device_info->io_width, get_emif_bus_width(emif));
1125 	writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
1126 
1127 	/*
1128 	 * Program external PHY control registers that are not frequency
1129 	 * dependent
1130 	 */
1131 	if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
1132 		return;
1133 	writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
1134 	writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
1135 	writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
1136 	writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
1137 	writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
1138 	writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
1139 	writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
1140 	writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
1141 	writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
1142 	writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
1143 	writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
1144 	writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
1145 	writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
1146 	writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
1147 	writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
1148 	writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
1149 	writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
1150 	writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
1151 	writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
1152 	writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
1153 	writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
1154 }
1155 
1156 static void get_default_timings(struct emif_data *emif)
1157 {
1158 	struct emif_platform_data *pd = emif->plat_data;
1159 
1160 	pd->timings		= lpddr2_jedec_timings;
1161 	pd->timings_arr_size	= ARRAY_SIZE(lpddr2_jedec_timings);
1162 
1163 	dev_warn(emif->dev, "%s: using default timings\n", __func__);
1164 }
1165 
1166 static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
1167 		u32 ip_rev, struct device *dev)
1168 {
1169 	int valid;
1170 
1171 	valid = (type == DDR_TYPE_LPDDR2_S4 ||
1172 			type == DDR_TYPE_LPDDR2_S2)
1173 		&& (density >= DDR_DENSITY_64Mb
1174 			&& density <= DDR_DENSITY_8Gb)
1175 		&& (io_width >= DDR_IO_WIDTH_8
1176 			&& io_width <= DDR_IO_WIDTH_32);
1177 
1178 	/* Combinations of EMIF and PHY revisions that we support today */
1179 	switch (ip_rev) {
1180 	case EMIF_4D:
1181 		valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
1182 		break;
1183 	case EMIF_4D5:
1184 		valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
1185 		break;
1186 	default:
1187 		valid = 0;
1188 	}
1189 
1190 	if (!valid)
1191 		dev_err(dev, "%s: invalid DDR details\n", __func__);
1192 	return valid;
1193 }
1194 
1195 static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
1196 		struct device *dev)
1197 {
1198 	int valid = 1;
1199 
1200 	if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
1201 		(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
1202 		valid = cust_cfgs->lpmode_freq_threshold &&
1203 			cust_cfgs->lpmode_timeout_performance &&
1204 			cust_cfgs->lpmode_timeout_power;
1205 
1206 	if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
1207 		valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
1208 
1209 	if (!valid)
1210 		dev_warn(dev, "%s: invalid custom configs\n", __func__);
1211 
1212 	return valid;
1213 }
1214 
1215 #if defined(CONFIG_OF)
1216 static void __init_or_module of_get_custom_configs(struct device_node *np_emif,
1217 		struct emif_data *emif)
1218 {
1219 	struct emif_custom_configs	*cust_cfgs = NULL;
1220 	int				len;
1221 	const __be32			*lpmode, *poll_intvl;
1222 
1223 	lpmode = of_get_property(np_emif, "low-power-mode", &len);
1224 	poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
1225 
1226 	if (lpmode || poll_intvl)
1227 		cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
1228 			GFP_KERNEL);
1229 
1230 	if (!cust_cfgs)
1231 		return;
1232 
1233 	if (lpmode) {
1234 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
1235 		cust_cfgs->lpmode = be32_to_cpup(lpmode);
1236 		of_property_read_u32(np_emif,
1237 				"low-power-mode-timeout-performance",
1238 				&cust_cfgs->lpmode_timeout_performance);
1239 		of_property_read_u32(np_emif,
1240 				"low-power-mode-timeout-power",
1241 				&cust_cfgs->lpmode_timeout_power);
1242 		of_property_read_u32(np_emif,
1243 				"low-power-mode-freq-threshold",
1244 				&cust_cfgs->lpmode_freq_threshold);
1245 	}
1246 
1247 	if (poll_intvl) {
1248 		cust_cfgs->mask |=
1249 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
1250 		cust_cfgs->temp_alert_poll_interval_ms =
1251 						be32_to_cpup(poll_intvl);
1252 	}
1253 
1254 	if (of_find_property(np_emif, "extended-temp-part", &len))
1255 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART;
1256 
1257 	if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
1258 		devm_kfree(emif->dev, cust_cfgs);
1259 		return;
1260 	}
1261 
1262 	emif->plat_data->custom_configs = cust_cfgs;
1263 }
1264 
1265 static void __init_or_module of_get_ddr_info(struct device_node *np_emif,
1266 		struct device_node *np_ddr,
1267 		struct ddr_device_info *dev_info)
1268 {
1269 	u32 density = 0, io_width = 0;
1270 	int len;
1271 
1272 	if (of_find_property(np_emif, "cs1-used", &len))
1273 		dev_info->cs1_used = true;
1274 
1275 	if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
1276 		dev_info->cal_resistors_per_cs = true;
1277 
1278 	if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s4"))
1279 		dev_info->type = DDR_TYPE_LPDDR2_S4;
1280 	else if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s2"))
1281 		dev_info->type = DDR_TYPE_LPDDR2_S2;
1282 
1283 	of_property_read_u32(np_ddr, "density", &density);
1284 	of_property_read_u32(np_ddr, "io-width", &io_width);
1285 
1286 	/* Convert from density in Mb to the density encoding in jedc_ddr.h */
1287 	if (density & (density - 1))
1288 		dev_info->density = 0;
1289 	else
1290 		dev_info->density = __fls(density) - 5;
1291 
1292 	/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
1293 	if (io_width & (io_width - 1))
1294 		dev_info->io_width = 0;
1295 	else
1296 		dev_info->io_width = __fls(io_width) - 1;
1297 }
1298 
1299 static struct emif_data * __init_or_module of_get_memory_device_details(
1300 		struct device_node *np_emif, struct device *dev)
1301 {
1302 	struct emif_data		*emif = NULL;
1303 	struct ddr_device_info		*dev_info = NULL;
1304 	struct emif_platform_data	*pd = NULL;
1305 	struct device_node		*np_ddr;
1306 	int				len;
1307 
1308 	np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
1309 	if (!np_ddr)
1310 		goto error;
1311 	emif	= devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
1312 	pd	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1313 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1314 
1315 	if (!emif || !pd || !dev_info) {
1316 		dev_err(dev, "%s: Out of memory!!\n",
1317 			__func__);
1318 		goto error;
1319 	}
1320 
1321 	emif->plat_data		= pd;
1322 	pd->device_info		= dev_info;
1323 	emif->dev		= dev;
1324 	emif->np_ddr		= np_ddr;
1325 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1326 
1327 	if (of_device_is_compatible(np_emif, "ti,emif-4d"))
1328 		emif->plat_data->ip_rev = EMIF_4D;
1329 	else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
1330 		emif->plat_data->ip_rev = EMIF_4D5;
1331 
1332 	of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
1333 
1334 	if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
1335 		pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
1336 
1337 	of_get_ddr_info(np_emif, np_ddr, dev_info);
1338 	if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
1339 			pd->device_info->io_width, pd->phy_type, pd->ip_rev,
1340 			emif->dev)) {
1341 		dev_err(dev, "%s: invalid device data!!\n", __func__);
1342 		goto error;
1343 	}
1344 	/*
1345 	 * For EMIF instances other than EMIF1 see if the devices connected
1346 	 * are exactly same as on EMIF1(which is typically the case). If so,
1347 	 * mark it as a duplicate of EMIF1. This will save some memory and
1348 	 * computation.
1349 	 */
1350 	if (emif1 && emif1->np_ddr == np_ddr) {
1351 		emif->duplicate = true;
1352 		goto out;
1353 	} else if (emif1) {
1354 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1355 			__func__);
1356 	}
1357 
1358 	of_get_custom_configs(np_emif, emif);
1359 	emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
1360 					emif->plat_data->device_info->type,
1361 					&emif->plat_data->timings_arr_size);
1362 
1363 	emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
1364 	goto out;
1365 
1366 error:
1367 	return NULL;
1368 out:
1369 	return emif;
1370 }
1371 
1372 #else
1373 
1374 static struct emif_data * __init_or_module of_get_memory_device_details(
1375 		struct device_node *np_emif, struct device *dev)
1376 {
1377 	return NULL;
1378 }
1379 #endif
1380 
1381 static struct emif_data *__init_or_module get_device_details(
1382 		struct platform_device *pdev)
1383 {
1384 	u32				size;
1385 	struct emif_data		*emif = NULL;
1386 	struct ddr_device_info		*dev_info;
1387 	struct emif_custom_configs	*cust_cfgs;
1388 	struct emif_platform_data	*pd;
1389 	struct device			*dev;
1390 	void				*temp;
1391 
1392 	pd = pdev->dev.platform_data;
1393 	dev = &pdev->dev;
1394 
1395 	if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
1396 			pd->device_info->density, pd->device_info->io_width,
1397 			pd->phy_type, pd->ip_rev, dev))) {
1398 		dev_err(dev, "%s: invalid device data\n", __func__);
1399 		goto error;
1400 	}
1401 
1402 	emif	= devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
1403 	temp	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1404 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1405 
1406 	if (!emif || !pd || !dev_info) {
1407 		dev_err(dev, "%s:%d: allocation error\n", __func__, __LINE__);
1408 		goto error;
1409 	}
1410 
1411 	memcpy(temp, pd, sizeof(*pd));
1412 	pd = temp;
1413 	memcpy(dev_info, pd->device_info, sizeof(*dev_info));
1414 
1415 	pd->device_info		= dev_info;
1416 	emif->plat_data		= pd;
1417 	emif->dev		= dev;
1418 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1419 
1420 	/*
1421 	 * For EMIF instances other than EMIF1 see if the devices connected
1422 	 * are exactly same as on EMIF1(which is typically the case). If so,
1423 	 * mark it as a duplicate of EMIF1 and skip copying timings data.
1424 	 * This will save some memory and some computation later.
1425 	 */
1426 	emif->duplicate = emif1 && (memcmp(dev_info,
1427 		emif1->plat_data->device_info,
1428 		sizeof(struct ddr_device_info)) == 0);
1429 
1430 	if (emif->duplicate) {
1431 		pd->timings = NULL;
1432 		pd->min_tck = NULL;
1433 		goto out;
1434 	} else if (emif1) {
1435 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1436 			__func__);
1437 	}
1438 
1439 	/*
1440 	 * Copy custom configs - ignore allocation error, if any, as
1441 	 * custom_configs is not very critical
1442 	 */
1443 	cust_cfgs = pd->custom_configs;
1444 	if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
1445 		temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
1446 		if (temp)
1447 			memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
1448 		else
1449 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1450 				__LINE__);
1451 		pd->custom_configs = temp;
1452 	}
1453 
1454 	/*
1455 	 * Copy timings and min-tck values from platform data. If it is not
1456 	 * available or if memory allocation fails, use JEDEC defaults
1457 	 */
1458 	size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
1459 	if (pd->timings) {
1460 		temp = devm_kzalloc(dev, size, GFP_KERNEL);
1461 		if (temp) {
1462 			memcpy(temp, pd->timings, size);
1463 			pd->timings = temp;
1464 		} else {
1465 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1466 				__LINE__);
1467 			get_default_timings(emif);
1468 		}
1469 	} else {
1470 		get_default_timings(emif);
1471 	}
1472 
1473 	if (pd->min_tck) {
1474 		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
1475 		if (temp) {
1476 			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
1477 			pd->min_tck = temp;
1478 		} else {
1479 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1480 				__LINE__);
1481 			pd->min_tck = &lpddr2_jedec_min_tck;
1482 		}
1483 	} else {
1484 		pd->min_tck = &lpddr2_jedec_min_tck;
1485 	}
1486 
1487 out:
1488 	return emif;
1489 
1490 error:
1491 	return NULL;
1492 }
1493 
1494 static int __init_or_module emif_probe(struct platform_device *pdev)
1495 {
1496 	struct emif_data	*emif;
1497 	struct resource		*res;
1498 	int			irq;
1499 
1500 	if (pdev->dev.of_node)
1501 		emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
1502 	else
1503 		emif = get_device_details(pdev);
1504 
1505 	if (!emif) {
1506 		pr_err("%s: error getting device data\n", __func__);
1507 		goto error;
1508 	}
1509 
1510 	list_add(&emif->node, &device_list);
1511 	emif->addressing = get_addressing_table(emif->plat_data->device_info);
1512 
1513 	/* Save pointers to each other in emif and device structures */
1514 	emif->dev = &pdev->dev;
1515 	platform_set_drvdata(pdev, emif);
1516 
1517 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1518 	emif->base = devm_ioremap_resource(emif->dev, res);
1519 	if (IS_ERR(emif->base))
1520 		goto error;
1521 
1522 	irq = platform_get_irq(pdev, 0);
1523 	if (irq < 0)
1524 		goto error;
1525 
1526 	emif_onetime_settings(emif);
1527 	emif_debugfs_init(emif);
1528 	disable_and_clear_all_interrupts(emif);
1529 	setup_interrupts(emif, irq);
1530 
1531 	/* One-time actions taken on probing the first device */
1532 	if (!emif1) {
1533 		emif1 = emif;
1534 		spin_lock_init(&emif_lock);
1535 
1536 		/*
1537 		 * TODO: register notifiers for frequency and voltage
1538 		 * change here once the respective frameworks are
1539 		 * available
1540 		 */
1541 	}
1542 
1543 	dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
1544 		__func__, emif->base, irq);
1545 
1546 	return 0;
1547 error:
1548 	return -ENODEV;
1549 }
1550 
1551 static int __exit emif_remove(struct platform_device *pdev)
1552 {
1553 	struct emif_data *emif = platform_get_drvdata(pdev);
1554 
1555 	emif_debugfs_exit(emif);
1556 
1557 	return 0;
1558 }
1559 
1560 static void emif_shutdown(struct platform_device *pdev)
1561 {
1562 	struct emif_data	*emif = platform_get_drvdata(pdev);
1563 
1564 	disable_and_clear_all_interrupts(emif);
1565 }
1566 
1567 static int get_emif_reg_values(struct emif_data *emif, u32 freq,
1568 		struct emif_regs *regs)
1569 {
1570 	u32				ip_rev, phy_type;
1571 	u32				cl, type;
1572 	const struct lpddr2_timings	*timings;
1573 	const struct lpddr2_min_tck	*min_tck;
1574 	const struct ddr_device_info	*device_info;
1575 	const struct lpddr2_addressing	*addressing;
1576 	struct emif_data		*emif_for_calc;
1577 	struct device			*dev;
1578 
1579 	dev = emif->dev;
1580 	/*
1581 	 * If the devices on this EMIF instance is duplicate of EMIF1,
1582 	 * use EMIF1 details for the calculation
1583 	 */
1584 	emif_for_calc	= emif->duplicate ? emif1 : emif;
1585 	timings		= get_timings_table(emif_for_calc, freq);
1586 	addressing	= emif_for_calc->addressing;
1587 	if (!timings || !addressing) {
1588 		dev_err(dev, "%s: not enough data available for %dHz",
1589 			__func__, freq);
1590 		return -1;
1591 	}
1592 
1593 	device_info	= emif_for_calc->plat_data->device_info;
1594 	type		= device_info->type;
1595 	ip_rev		= emif_for_calc->plat_data->ip_rev;
1596 	phy_type	= emif_for_calc->plat_data->phy_type;
1597 
1598 	min_tck		= emif_for_calc->plat_data->min_tck;
1599 
1600 	set_ddr_clk_period(freq);
1601 
1602 	regs->ref_ctrl_shdw = get_sdram_ref_ctrl_shdw(freq, addressing);
1603 	regs->sdram_tim1_shdw = get_sdram_tim_1_shdw(timings, min_tck,
1604 			addressing);
1605 	regs->sdram_tim2_shdw = get_sdram_tim_2_shdw(timings, min_tck,
1606 			addressing, type);
1607 	regs->sdram_tim3_shdw = get_sdram_tim_3_shdw(timings, min_tck,
1608 		addressing, type, ip_rev, EMIF_NORMAL_TIMINGS);
1609 
1610 	cl = get_cl(emif);
1611 
1612 	if (phy_type == EMIF_PHY_TYPE_ATTILAPHY && ip_rev == EMIF_4D) {
1613 		regs->phy_ctrl_1_shdw = get_ddr_phy_ctrl_1_attilaphy_4d(
1614 			timings, freq, cl);
1615 	} else if (phy_type == EMIF_PHY_TYPE_INTELLIPHY && ip_rev == EMIF_4D5) {
1616 		regs->phy_ctrl_1_shdw = get_phy_ctrl_1_intelliphy_4d5(freq, cl);
1617 		regs->ext_phy_ctrl_2_shdw = get_ext_phy_ctrl_2_intelliphy_4d5();
1618 		regs->ext_phy_ctrl_3_shdw = get_ext_phy_ctrl_3_intelliphy_4d5();
1619 		regs->ext_phy_ctrl_4_shdw = get_ext_phy_ctrl_4_intelliphy_4d5();
1620 	} else {
1621 		return -1;
1622 	}
1623 
1624 	/* Only timeout values in pwr_mgmt_ctrl_shdw register */
1625 	regs->pwr_mgmt_ctrl_shdw =
1626 		get_pwr_mgmt_ctrl(freq, emif_for_calc, ip_rev) &
1627 		(CS_TIM_MASK | SR_TIM_MASK | PD_TIM_MASK);
1628 
1629 	if (ip_rev & EMIF_4D) {
1630 		regs->read_idle_ctrl_shdw_normal =
1631 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_STABLE);
1632 
1633 		regs->read_idle_ctrl_shdw_volt_ramp =
1634 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1635 	} else if (ip_rev & EMIF_4D5) {
1636 		regs->dll_calib_ctrl_shdw_normal =
1637 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_STABLE);
1638 
1639 		regs->dll_calib_ctrl_shdw_volt_ramp =
1640 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1641 	}
1642 
1643 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
1644 		regs->ref_ctrl_shdw_derated = get_sdram_ref_ctrl_shdw(freq / 4,
1645 			addressing);
1646 
1647 		regs->sdram_tim1_shdw_derated =
1648 			get_sdram_tim_1_shdw_derated(timings, min_tck,
1649 				addressing);
1650 
1651 		regs->sdram_tim3_shdw_derated = get_sdram_tim_3_shdw(timings,
1652 			min_tck, addressing, type, ip_rev,
1653 			EMIF_DERATED_TIMINGS);
1654 	}
1655 
1656 	regs->freq = freq;
1657 
1658 	return 0;
1659 }
1660 
1661 /*
1662  * get_regs() - gets the cached emif_regs structure for a given EMIF instance
1663  * given frequency(freq):
1664  *
1665  * As an optimisation, every EMIF instance other than EMIF1 shares the
1666  * register cache with EMIF1 if the devices connected on this instance
1667  * are same as that on EMIF1(indicated by the duplicate flag)
1668  *
1669  * If we do not have an entry corresponding to the frequency given, we
1670  * allocate a new entry and calculate the values
1671  *
1672  * Upon finding the right reg dump, save it in curr_regs. It can be
1673  * directly used for thermal de-rating and voltage ramping changes.
1674  */
1675 static struct emif_regs *get_regs(struct emif_data *emif, u32 freq)
1676 {
1677 	int			i;
1678 	struct emif_regs	**regs_cache;
1679 	struct emif_regs	*regs = NULL;
1680 	struct device		*dev;
1681 
1682 	dev = emif->dev;
1683 	if (emif->curr_regs && emif->curr_regs->freq == freq) {
1684 		dev_dbg(dev, "%s: using curr_regs - %u Hz", __func__, freq);
1685 		return emif->curr_regs;
1686 	}
1687 
1688 	if (emif->duplicate)
1689 		regs_cache = emif1->regs_cache;
1690 	else
1691 		regs_cache = emif->regs_cache;
1692 
1693 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
1694 		if (regs_cache[i]->freq == freq) {
1695 			regs = regs_cache[i];
1696 			dev_dbg(dev,
1697 				"%s: reg dump found in reg cache for %u Hz\n",
1698 				__func__, freq);
1699 			break;
1700 		}
1701 	}
1702 
1703 	/*
1704 	 * If we don't have an entry for this frequency in the cache create one
1705 	 * and calculate the values
1706 	 */
1707 	if (!regs) {
1708 		regs = devm_kzalloc(emif->dev, sizeof(*regs), GFP_ATOMIC);
1709 		if (!regs)
1710 			return NULL;
1711 
1712 		if (get_emif_reg_values(emif, freq, regs)) {
1713 			devm_kfree(emif->dev, regs);
1714 			return NULL;
1715 		}
1716 
1717 		/*
1718 		 * Now look for an un-used entry in the cache and save the
1719 		 * newly created struct. If there are no free entries
1720 		 * over-write the last entry
1721 		 */
1722 		for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++)
1723 			;
1724 
1725 		if (i >= EMIF_MAX_NUM_FREQUENCIES) {
1726 			dev_warn(dev, "%s: regs_cache full - reusing a slot!!\n",
1727 				__func__);
1728 			i = EMIF_MAX_NUM_FREQUENCIES - 1;
1729 			devm_kfree(emif->dev, regs_cache[i]);
1730 		}
1731 		regs_cache[i] = regs;
1732 	}
1733 
1734 	return regs;
1735 }
1736 
1737 static void do_volt_notify_handling(struct emif_data *emif, u32 volt_state)
1738 {
1739 	dev_dbg(emif->dev, "%s: voltage notification : %d", __func__,
1740 		volt_state);
1741 
1742 	if (!emif->curr_regs) {
1743 		dev_err(emif->dev,
1744 			"%s: volt-notify before registers are ready: %d\n",
1745 			__func__, volt_state);
1746 		return;
1747 	}
1748 
1749 	setup_volt_sensitive_regs(emif, emif->curr_regs, volt_state);
1750 }
1751 
1752 /*
1753  * TODO: voltage notify handling should be hooked up to
1754  * regulator framework as soon as the necessary support
1755  * is available in mainline kernel. This function is un-used
1756  * right now.
1757  */
1758 static void __attribute__((unused)) volt_notify_handling(u32 volt_state)
1759 {
1760 	struct emif_data *emif;
1761 
1762 	spin_lock_irqsave(&emif_lock, irq_state);
1763 
1764 	list_for_each_entry(emif, &device_list, node)
1765 		do_volt_notify_handling(emif, volt_state);
1766 	do_freq_update();
1767 
1768 	spin_unlock_irqrestore(&emif_lock, irq_state);
1769 }
1770 
1771 static void do_freq_pre_notify_handling(struct emif_data *emif, u32 new_freq)
1772 {
1773 	struct emif_regs *regs;
1774 
1775 	regs = get_regs(emif, new_freq);
1776 	if (!regs)
1777 		return;
1778 
1779 	emif->curr_regs = regs;
1780 
1781 	/*
1782 	 * Update the shadow registers:
1783 	 * Temperature and voltage-ramp sensitive settings are also configured
1784 	 * in terms of DDR cycles. So, we need to update them too when there
1785 	 * is a freq change
1786 	 */
1787 	dev_dbg(emif->dev, "%s: setting up shadow registers for %uHz",
1788 		__func__, new_freq);
1789 	setup_registers(emif, regs);
1790 	setup_temperature_sensitive_regs(emif, regs);
1791 	setup_volt_sensitive_regs(emif, regs, DDR_VOLTAGE_STABLE);
1792 
1793 	/*
1794 	 * Part of workaround for errata i728. See do_freq_update()
1795 	 * for more details
1796 	 */
1797 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1798 		set_lpmode(emif, EMIF_LP_MODE_DISABLE);
1799 }
1800 
1801 /*
1802  * TODO: frequency notify handling should be hooked up to
1803  * clock framework as soon as the necessary support is
1804  * available in mainline kernel. This function is un-used
1805  * right now.
1806  */
1807 static void __attribute__((unused)) freq_pre_notify_handling(u32 new_freq)
1808 {
1809 	struct emif_data *emif;
1810 
1811 	/*
1812 	 * NOTE: we are taking the spin-lock here and releases it
1813 	 * only in post-notifier. This doesn't look good and
1814 	 * Sparse complains about it, but this seems to be
1815 	 * un-avoidable. We need to lock a sequence of events
1816 	 * that is split between EMIF and clock framework.
1817 	 *
1818 	 * 1. EMIF driver updates EMIF timings in shadow registers in the
1819 	 *    frequency pre-notify callback from clock framework
1820 	 * 2. clock framework sets up the registers for the new frequency
1821 	 * 3. clock framework initiates a hw-sequence that updates
1822 	 *    the frequency EMIF timings synchronously.
1823 	 *
1824 	 * All these 3 steps should be performed as an atomic operation
1825 	 * vis-a-vis similar sequence in the EMIF interrupt handler
1826 	 * for temperature events. Otherwise, there could be race
1827 	 * conditions that could result in incorrect EMIF timings for
1828 	 * a given frequency
1829 	 */
1830 	spin_lock_irqsave(&emif_lock, irq_state);
1831 
1832 	list_for_each_entry(emif, &device_list, node)
1833 		do_freq_pre_notify_handling(emif, new_freq);
1834 }
1835 
1836 static void do_freq_post_notify_handling(struct emif_data *emif)
1837 {
1838 	/*
1839 	 * Part of workaround for errata i728. See do_freq_update()
1840 	 * for more details
1841 	 */
1842 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1843 		set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
1844 }
1845 
1846 /*
1847  * TODO: frequency notify handling should be hooked up to
1848  * clock framework as soon as the necessary support is
1849  * available in mainline kernel. This function is un-used
1850  * right now.
1851  */
1852 static void __attribute__((unused)) freq_post_notify_handling(void)
1853 {
1854 	struct emif_data *emif;
1855 
1856 	list_for_each_entry(emif, &device_list, node)
1857 		do_freq_post_notify_handling(emif);
1858 
1859 	/*
1860 	 * Lock is done in pre-notify handler. See freq_pre_notify_handling()
1861 	 * for more details
1862 	 */
1863 	spin_unlock_irqrestore(&emif_lock, irq_state);
1864 }
1865 
1866 #if defined(CONFIG_OF)
1867 static const struct of_device_id emif_of_match[] = {
1868 		{ .compatible = "ti,emif-4d" },
1869 		{ .compatible = "ti,emif-4d5" },
1870 		{},
1871 };
1872 MODULE_DEVICE_TABLE(of, emif_of_match);
1873 #endif
1874 
1875 static struct platform_driver emif_driver = {
1876 	.remove		= __exit_p(emif_remove),
1877 	.shutdown	= emif_shutdown,
1878 	.driver = {
1879 		.name = "emif",
1880 		.of_match_table = of_match_ptr(emif_of_match),
1881 	},
1882 };
1883 
1884 module_platform_driver_probe(emif_driver, emif_probe);
1885 
1886 MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
1887 MODULE_LICENSE("GPL");
1888 MODULE_ALIAS("platform:emif");
1889 MODULE_AUTHOR("Texas Instruments Inc");
1890