xref: /openbmc/linux/drivers/memory/emif.c (revision b593bce5)
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 static int emif_regdump_open(struct inode *inode, struct file *file)
135 {
136 	return single_open(file, emif_regdump_show, inode->i_private);
137 }
138 
139 static const struct file_operations emif_regdump_fops = {
140 	.open			= emif_regdump_open,
141 	.read			= seq_read,
142 	.release		= single_release,
143 };
144 
145 static int emif_mr4_show(struct seq_file *s, void *unused)
146 {
147 	struct emif_data *emif = s->private;
148 
149 	seq_printf(s, "MR4=%d\n", emif->temperature_level);
150 	return 0;
151 }
152 
153 static int emif_mr4_open(struct inode *inode, struct file *file)
154 {
155 	return single_open(file, emif_mr4_show, inode->i_private);
156 }
157 
158 static const struct file_operations emif_mr4_fops = {
159 	.open			= emif_mr4_open,
160 	.read			= seq_read,
161 	.release		= single_release,
162 };
163 
164 static int __init_or_module emif_debugfs_init(struct emif_data *emif)
165 {
166 	struct dentry	*dentry;
167 	int		ret;
168 
169 	dentry = debugfs_create_dir(dev_name(emif->dev), NULL);
170 	if (!dentry) {
171 		ret = -ENOMEM;
172 		goto err0;
173 	}
174 	emif->debugfs_root = dentry;
175 
176 	dentry = debugfs_create_file("regcache_dump", S_IRUGO,
177 			emif->debugfs_root, emif, &emif_regdump_fops);
178 	if (!dentry) {
179 		ret = -ENOMEM;
180 		goto err1;
181 	}
182 
183 	dentry = debugfs_create_file("mr4", S_IRUGO,
184 			emif->debugfs_root, emif, &emif_mr4_fops);
185 	if (!dentry) {
186 		ret = -ENOMEM;
187 		goto err1;
188 	}
189 
190 	return 0;
191 err1:
192 	debugfs_remove_recursive(emif->debugfs_root);
193 err0:
194 	return ret;
195 }
196 
197 static void __exit emif_debugfs_exit(struct emif_data *emif)
198 {
199 	debugfs_remove_recursive(emif->debugfs_root);
200 	emif->debugfs_root = NULL;
201 }
202 #else
203 static inline int __init_or_module emif_debugfs_init(struct emif_data *emif)
204 {
205 	return 0;
206 }
207 
208 static inline void __exit emif_debugfs_exit(struct emif_data *emif)
209 {
210 }
211 #endif
212 
213 /*
214  * Calculate the period of DDR clock from frequency value
215  */
216 static void set_ddr_clk_period(u32 freq)
217 {
218 	/* Divide 10^12 by frequency to get period in ps */
219 	t_ck = (u32)DIV_ROUND_UP_ULL(1000000000000ull, freq);
220 }
221 
222 /*
223  * Get bus width used by EMIF. Note that this may be different from the
224  * bus width of the DDR devices used. For instance two 16-bit DDR devices
225  * may be connected to a given CS of EMIF. In this case bus width as far
226  * as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
227  */
228 static u32 get_emif_bus_width(struct emif_data *emif)
229 {
230 	u32		width;
231 	void __iomem	*base = emif->base;
232 
233 	width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
234 			>> NARROW_MODE_SHIFT;
235 	width = width == 0 ? 32 : 16;
236 
237 	return width;
238 }
239 
240 /*
241  * Get the CL from SDRAM_CONFIG register
242  */
243 static u32 get_cl(struct emif_data *emif)
244 {
245 	u32		cl;
246 	void __iomem	*base = emif->base;
247 
248 	cl = (readl(base + EMIF_SDRAM_CONFIG) & CL_MASK) >> CL_SHIFT;
249 
250 	return cl;
251 }
252 
253 static void set_lpmode(struct emif_data *emif, u8 lpmode)
254 {
255 	u32 temp;
256 	void __iomem *base = emif->base;
257 
258 	/*
259 	 * Workaround for errata i743 - LPDDR2 Power-Down State is Not
260 	 * Efficient
261 	 *
262 	 * i743 DESCRIPTION:
263 	 * The EMIF supports power-down state for low power. The EMIF
264 	 * automatically puts the SDRAM into power-down after the memory is
265 	 * not accessed for a defined number of cycles and the
266 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set to 0x4.
267 	 * As the EMIF supports automatic output impedance calibration, a ZQ
268 	 * calibration long command is issued every time it exits active
269 	 * power-down and precharge power-down modes. The EMIF waits and
270 	 * blocks any other command during this calibration.
271 	 * The EMIF does not allow selective disabling of ZQ calibration upon
272 	 * exit of power-down mode. Due to very short periods of power-down
273 	 * cycles, ZQ calibration overhead creates bandwidth issues and
274 	 * increases overall system power consumption. On the other hand,
275 	 * issuing ZQ calibration long commands when exiting self-refresh is
276 	 * still required.
277 	 *
278 	 * WORKAROUND
279 	 * Because there is no power consumption benefit of the power-down due
280 	 * to the calibration and there is a performance risk, the guideline
281 	 * is to not allow power-down state and, therefore, to not have set
282 	 * the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field to 0x4.
283 	 */
284 	if ((emif->plat_data->ip_rev == EMIF_4D) &&
285 	    (EMIF_LP_MODE_PWR_DN == lpmode)) {
286 		WARN_ONCE(1,
287 			  "REG_LP_MODE = LP_MODE_PWR_DN(4) is prohibited by"
288 			  "erratum i743 switch to LP_MODE_SELF_REFRESH(2)\n");
289 		/* rollback LP_MODE to Self-refresh mode */
290 		lpmode = EMIF_LP_MODE_SELF_REFRESH;
291 	}
292 
293 	temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
294 	temp &= ~LP_MODE_MASK;
295 	temp |= (lpmode << LP_MODE_SHIFT);
296 	writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
297 }
298 
299 static void do_freq_update(void)
300 {
301 	struct emif_data *emif;
302 
303 	/*
304 	 * Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
305 	 *
306 	 * i728 DESCRIPTION:
307 	 * The EMIF automatically puts the SDRAM into self-refresh mode
308 	 * after the EMIF has not performed accesses during
309 	 * EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
310 	 * and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
311 	 * to 0x2. If during a small window the following three events
312 	 * occur:
313 	 * - The SR_TIMING counter expires
314 	 * - And frequency change is requested
315 	 * - And OCP access is requested
316 	 * Then it causes instable clock on the DDR interface.
317 	 *
318 	 * WORKAROUND
319 	 * To avoid the occurrence of the three events, the workaround
320 	 * is to disable the self-refresh when requesting a frequency
321 	 * change. Before requesting a frequency change the software must
322 	 * program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
323 	 * frequency change has been done, the software can reprogram
324 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
325 	 */
326 	list_for_each_entry(emif, &device_list, node) {
327 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
328 			set_lpmode(emif, EMIF_LP_MODE_DISABLE);
329 	}
330 
331 	/*
332 	 * TODO: Do FREQ_UPDATE here when an API
333 	 * is available for this as part of the new
334 	 * clock framework
335 	 */
336 
337 	list_for_each_entry(emif, &device_list, node) {
338 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
339 			set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
340 	}
341 }
342 
343 /* Find addressing table entry based on the device's type and density */
344 static const struct lpddr2_addressing *get_addressing_table(
345 	const struct ddr_device_info *device_info)
346 {
347 	u32		index, type, density;
348 
349 	type = device_info->type;
350 	density = device_info->density;
351 
352 	switch (type) {
353 	case DDR_TYPE_LPDDR2_S4:
354 		index = density - 1;
355 		break;
356 	case DDR_TYPE_LPDDR2_S2:
357 		switch (density) {
358 		case DDR_DENSITY_1Gb:
359 		case DDR_DENSITY_2Gb:
360 			index = density + 3;
361 			break;
362 		default:
363 			index = density - 1;
364 		}
365 		break;
366 	default:
367 		return NULL;
368 	}
369 
370 	return &lpddr2_jedec_addressing_table[index];
371 }
372 
373 /*
374  * Find the the right timing table from the array of timing
375  * tables of the device using DDR clock frequency
376  */
377 static const struct lpddr2_timings *get_timings_table(struct emif_data *emif,
378 		u32 freq)
379 {
380 	u32				i, min, max, freq_nearest;
381 	const struct lpddr2_timings	*timings = NULL;
382 	const struct lpddr2_timings	*timings_arr = emif->plat_data->timings;
383 	struct				device *dev = emif->dev;
384 
385 	/* Start with a very high frequency - 1GHz */
386 	freq_nearest = 1000000000;
387 
388 	/*
389 	 * Find the timings table such that:
390 	 *  1. the frequency range covers the required frequency(safe) AND
391 	 *  2. the max_freq is closest to the required frequency(optimal)
392 	 */
393 	for (i = 0; i < emif->plat_data->timings_arr_size; i++) {
394 		max = timings_arr[i].max_freq;
395 		min = timings_arr[i].min_freq;
396 		if ((freq >= min) && (freq <= max) && (max < freq_nearest)) {
397 			freq_nearest = max;
398 			timings = &timings_arr[i];
399 		}
400 	}
401 
402 	if (!timings)
403 		dev_err(dev, "%s: couldn't find timings for - %dHz\n",
404 			__func__, freq);
405 
406 	dev_dbg(dev, "%s: timings table: freq %d, speed bin freq %d\n",
407 		__func__, freq, freq_nearest);
408 
409 	return timings;
410 }
411 
412 static u32 get_sdram_ref_ctrl_shdw(u32 freq,
413 		const struct lpddr2_addressing *addressing)
414 {
415 	u32 ref_ctrl_shdw = 0, val = 0, freq_khz, t_refi;
416 
417 	/* Scale down frequency and t_refi to avoid overflow */
418 	freq_khz = freq / 1000;
419 	t_refi = addressing->tREFI_ns / 100;
420 
421 	/*
422 	 * refresh rate to be set is 'tREFI(in us) * freq in MHz
423 	 * division by 10000 to account for change in units
424 	 */
425 	val = t_refi * freq_khz / 10000;
426 	ref_ctrl_shdw |= val << REFRESH_RATE_SHIFT;
427 
428 	return ref_ctrl_shdw;
429 }
430 
431 static u32 get_sdram_tim_1_shdw(const struct lpddr2_timings *timings,
432 		const struct lpddr2_min_tck *min_tck,
433 		const struct lpddr2_addressing *addressing)
434 {
435 	u32 tim1 = 0, val = 0;
436 
437 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
438 	tim1 |= val << T_WTR_SHIFT;
439 
440 	if (addressing->num_banks == B8)
441 		val = DIV_ROUND_UP(timings->tFAW, t_ck*4);
442 	else
443 		val = max(min_tck->tRRD, DIV_ROUND_UP(timings->tRRD, t_ck));
444 	tim1 |= (val - 1) << T_RRD_SHIFT;
445 
446 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab, t_ck) - 1;
447 	tim1 |= val << T_RC_SHIFT;
448 
449 	val = max(min_tck->tRASmin, DIV_ROUND_UP(timings->tRAS_min, t_ck));
450 	tim1 |= (val - 1) << T_RAS_SHIFT;
451 
452 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
453 	tim1 |= val << T_WR_SHIFT;
454 
455 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD, t_ck)) - 1;
456 	tim1 |= val << T_RCD_SHIFT;
457 
458 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab, t_ck)) - 1;
459 	tim1 |= val << T_RP_SHIFT;
460 
461 	return tim1;
462 }
463 
464 static u32 get_sdram_tim_1_shdw_derated(const struct lpddr2_timings *timings,
465 		const struct lpddr2_min_tck *min_tck,
466 		const struct lpddr2_addressing *addressing)
467 {
468 	u32 tim1 = 0, val = 0;
469 
470 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
471 	tim1 = val << T_WTR_SHIFT;
472 
473 	/*
474 	 * tFAW is approximately 4 times tRRD. So add 1875*4 = 7500ps
475 	 * to tFAW for de-rating
476 	 */
477 	if (addressing->num_banks == B8) {
478 		val = DIV_ROUND_UP(timings->tFAW + 7500, 4 * t_ck) - 1;
479 	} else {
480 		val = DIV_ROUND_UP(timings->tRRD + 1875, t_ck);
481 		val = max(min_tck->tRRD, val) - 1;
482 	}
483 	tim1 |= val << T_RRD_SHIFT;
484 
485 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab + 1875, t_ck);
486 	tim1 |= (val - 1) << T_RC_SHIFT;
487 
488 	val = DIV_ROUND_UP(timings->tRAS_min + 1875, t_ck);
489 	val = max(min_tck->tRASmin, val) - 1;
490 	tim1 |= val << T_RAS_SHIFT;
491 
492 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
493 	tim1 |= val << T_WR_SHIFT;
494 
495 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD + 1875, t_ck));
496 	tim1 |= (val - 1) << T_RCD_SHIFT;
497 
498 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab + 1875, t_ck));
499 	tim1 |= (val - 1) << T_RP_SHIFT;
500 
501 	return tim1;
502 }
503 
504 static u32 get_sdram_tim_2_shdw(const struct lpddr2_timings *timings,
505 		const struct lpddr2_min_tck *min_tck,
506 		const struct lpddr2_addressing *addressing,
507 		u32 type)
508 {
509 	u32 tim2 = 0, val = 0;
510 
511 	val = min_tck->tCKE - 1;
512 	tim2 |= val << T_CKE_SHIFT;
513 
514 	val = max(min_tck->tRTP, DIV_ROUND_UP(timings->tRTP, t_ck)) - 1;
515 	tim2 |= val << T_RTP_SHIFT;
516 
517 	/* tXSNR = tRFCab_ps + 10 ns(tRFCab_ps for LPDDR2). */
518 	val = DIV_ROUND_UP(addressing->tRFCab_ps + 10000, t_ck) - 1;
519 	tim2 |= val << T_XSNR_SHIFT;
520 
521 	/* XSRD same as XSNR for LPDDR2 */
522 	tim2 |= val << T_XSRD_SHIFT;
523 
524 	val = max(min_tck->tXP, DIV_ROUND_UP(timings->tXP, t_ck)) - 1;
525 	tim2 |= val << T_XP_SHIFT;
526 
527 	return tim2;
528 }
529 
530 static u32 get_sdram_tim_3_shdw(const struct lpddr2_timings *timings,
531 		const struct lpddr2_min_tck *min_tck,
532 		const struct lpddr2_addressing *addressing,
533 		u32 type, u32 ip_rev, u32 derated)
534 {
535 	u32 tim3 = 0, val = 0, t_dqsck;
536 
537 	val = timings->tRAS_max_ns / addressing->tREFI_ns - 1;
538 	val = val > 0xF ? 0xF : val;
539 	tim3 |= val << T_RAS_MAX_SHIFT;
540 
541 	val = DIV_ROUND_UP(addressing->tRFCab_ps, t_ck) - 1;
542 	tim3 |= val << T_RFC_SHIFT;
543 
544 	t_dqsck = (derated == EMIF_DERATED_TIMINGS) ?
545 		timings->tDQSCK_max_derated : timings->tDQSCK_max;
546 	if (ip_rev == EMIF_4D5)
547 		val = DIV_ROUND_UP(t_dqsck + 1000, t_ck) - 1;
548 	else
549 		val = DIV_ROUND_UP(t_dqsck, t_ck) - 1;
550 
551 	tim3 |= val << T_TDQSCKMAX_SHIFT;
552 
553 	val = DIV_ROUND_UP(timings->tZQCS, t_ck) - 1;
554 	tim3 |= val << ZQ_ZQCS_SHIFT;
555 
556 	val = DIV_ROUND_UP(timings->tCKESR, t_ck);
557 	val = max(min_tck->tCKESR, val) - 1;
558 	tim3 |= val << T_CKESR_SHIFT;
559 
560 	if (ip_rev == EMIF_4D5) {
561 		tim3 |= (EMIF_T_CSTA - 1) << T_CSTA_SHIFT;
562 
563 		val = DIV_ROUND_UP(EMIF_T_PDLL_UL, 128) - 1;
564 		tim3 |= val << T_PDLL_UL_SHIFT;
565 	}
566 
567 	return tim3;
568 }
569 
570 static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
571 		bool cs1_used, bool cal_resistors_per_cs)
572 {
573 	u32 zq = 0, val = 0;
574 
575 	val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
576 	zq |= val << ZQ_REFINTERVAL_SHIFT;
577 
578 	val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
579 	zq |= val << ZQ_ZQCL_MULT_SHIFT;
580 
581 	val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
582 	zq |= val << ZQ_ZQINIT_MULT_SHIFT;
583 
584 	zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
585 
586 	if (cal_resistors_per_cs)
587 		zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
588 	else
589 		zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
590 
591 	zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
592 
593 	val = cs1_used ? 1 : 0;
594 	zq |= val << ZQ_CS1EN_SHIFT;
595 
596 	return zq;
597 }
598 
599 static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
600 		const struct emif_custom_configs *custom_configs, bool cs1_used,
601 		u32 sdram_io_width, u32 emif_bus_width)
602 {
603 	u32 alert = 0, interval, devcnt;
604 
605 	if (custom_configs && (custom_configs->mask &
606 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
607 		interval = custom_configs->temp_alert_poll_interval_ms;
608 	else
609 		interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
610 
611 	interval *= 1000000;			/* Convert to ns */
612 	interval /= addressing->tREFI_ns;	/* Convert to refresh cycles */
613 	alert |= (interval << TA_REFINTERVAL_SHIFT);
614 
615 	/*
616 	 * sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
617 	 * also to this form and subtract to get TA_DEVCNT, which is
618 	 * in log2(x) form.
619 	 */
620 	emif_bus_width = __fls(emif_bus_width) - 1;
621 	devcnt = emif_bus_width - sdram_io_width;
622 	alert |= devcnt << TA_DEVCNT_SHIFT;
623 
624 	/* DEVWDT is in 'log2(x) - 3' form */
625 	alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
626 
627 	alert |= 1 << TA_SFEXITEN_SHIFT;
628 	alert |= 1 << TA_CS0EN_SHIFT;
629 	alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
630 
631 	return alert;
632 }
633 
634 static u32 get_read_idle_ctrl_shdw(u8 volt_ramp)
635 {
636 	u32 idle = 0, val = 0;
637 
638 	/*
639 	 * Maximum value in normal conditions and increased frequency
640 	 * when voltage is ramping
641 	 */
642 	if (volt_ramp)
643 		val = READ_IDLE_INTERVAL_DVFS / t_ck / 64 - 1;
644 	else
645 		val = 0x1FF;
646 
647 	/*
648 	 * READ_IDLE_CTRL register in EMIF4D has same offset and fields
649 	 * as DLL_CALIB_CTRL in EMIF4D5, so use the same shifts
650 	 */
651 	idle |= val << DLL_CALIB_INTERVAL_SHIFT;
652 	idle |= EMIF_READ_IDLE_LEN_VAL << ACK_WAIT_SHIFT;
653 
654 	return idle;
655 }
656 
657 static u32 get_dll_calib_ctrl_shdw(u8 volt_ramp)
658 {
659 	u32 calib = 0, val = 0;
660 
661 	if (volt_ramp == DDR_VOLTAGE_RAMPING)
662 		val = DLL_CALIB_INTERVAL_DVFS / t_ck / 16 - 1;
663 	else
664 		val = 0; /* Disabled when voltage is stable */
665 
666 	calib |= val << DLL_CALIB_INTERVAL_SHIFT;
667 	calib |= DLL_CALIB_ACK_WAIT_VAL << ACK_WAIT_SHIFT;
668 
669 	return calib;
670 }
671 
672 static u32 get_ddr_phy_ctrl_1_attilaphy_4d(const struct lpddr2_timings *timings,
673 	u32 freq, u8 RL)
674 {
675 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_ATTILAPHY, val = 0;
676 
677 	val = RL + DIV_ROUND_UP(timings->tDQSCK_max, t_ck) - 1;
678 	phy |= val << READ_LATENCY_SHIFT_4D;
679 
680 	if (freq <= 100000000)
681 		val = EMIF_DLL_SLAVE_DLY_CTRL_100_MHZ_AND_LESS_ATTILAPHY;
682 	else if (freq <= 200000000)
683 		val = EMIF_DLL_SLAVE_DLY_CTRL_200_MHZ_ATTILAPHY;
684 	else
685 		val = EMIF_DLL_SLAVE_DLY_CTRL_400_MHZ_ATTILAPHY;
686 
687 	phy |= val << DLL_SLAVE_DLY_CTRL_SHIFT_4D;
688 
689 	return phy;
690 }
691 
692 static u32 get_phy_ctrl_1_intelliphy_4d5(u32 freq, u8 cl)
693 {
694 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_INTELLIPHY, half_delay;
695 
696 	/*
697 	 * DLL operates at 266 MHz. If DDR frequency is near 266 MHz,
698 	 * half-delay is not needed else set half-delay
699 	 */
700 	if (freq >= 265000000 && freq < 267000000)
701 		half_delay = 0;
702 	else
703 		half_delay = 1;
704 
705 	phy |= half_delay << DLL_HALF_DELAY_SHIFT_4D5;
706 	phy |= ((cl + DIV_ROUND_UP(EMIF_PHY_TOTAL_READ_LATENCY_INTELLIPHY_PS,
707 			t_ck) - 1) << READ_LATENCY_SHIFT_4D5);
708 
709 	return phy;
710 }
711 
712 static u32 get_ext_phy_ctrl_2_intelliphy_4d5(void)
713 {
714 	u32 fifo_we_slave_ratio;
715 
716 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
717 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
718 
719 	return fifo_we_slave_ratio | fifo_we_slave_ratio << 11 |
720 		fifo_we_slave_ratio << 22;
721 }
722 
723 static u32 get_ext_phy_ctrl_3_intelliphy_4d5(void)
724 {
725 	u32 fifo_we_slave_ratio;
726 
727 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
728 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
729 
730 	return fifo_we_slave_ratio >> 10 | fifo_we_slave_ratio << 1 |
731 		fifo_we_slave_ratio << 12 | fifo_we_slave_ratio << 23;
732 }
733 
734 static u32 get_ext_phy_ctrl_4_intelliphy_4d5(void)
735 {
736 	u32 fifo_we_slave_ratio;
737 
738 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
739 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
740 
741 	return fifo_we_slave_ratio >> 9 | fifo_we_slave_ratio << 2 |
742 		fifo_we_slave_ratio << 13;
743 }
744 
745 static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
746 {
747 	u32 pwr_mgmt_ctrl	= 0, timeout;
748 	u32 lpmode		= EMIF_LP_MODE_SELF_REFRESH;
749 	u32 timeout_perf	= EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
750 	u32 timeout_pwr		= EMIF_LP_MODE_TIMEOUT_POWER;
751 	u32 freq_threshold	= EMIF_LP_MODE_FREQ_THRESHOLD;
752 	u32 mask;
753 	u8 shift;
754 
755 	struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
756 
757 	if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
758 		lpmode		= cust_cfgs->lpmode;
759 		timeout_perf	= cust_cfgs->lpmode_timeout_performance;
760 		timeout_pwr	= cust_cfgs->lpmode_timeout_power;
761 		freq_threshold  = cust_cfgs->lpmode_freq_threshold;
762 	}
763 
764 	/* Timeout based on DDR frequency */
765 	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
766 
767 	/*
768 	 * The value to be set in register is "log2(timeout) - 3"
769 	 * if timeout < 16 load 0 in register
770 	 * if timeout is not a power of 2, round to next highest power of 2
771 	 */
772 	if (timeout < 16) {
773 		timeout = 0;
774 	} else {
775 		if (timeout & (timeout - 1))
776 			timeout <<= 1;
777 		timeout = __fls(timeout) - 3;
778 	}
779 
780 	switch (lpmode) {
781 	case EMIF_LP_MODE_CLOCK_STOP:
782 		shift = CS_TIM_SHIFT;
783 		mask = CS_TIM_MASK;
784 		break;
785 	case EMIF_LP_MODE_SELF_REFRESH:
786 		/* Workaround for errata i735 */
787 		if (timeout < 6)
788 			timeout = 6;
789 
790 		shift = SR_TIM_SHIFT;
791 		mask = SR_TIM_MASK;
792 		break;
793 	case EMIF_LP_MODE_PWR_DN:
794 		shift = PD_TIM_SHIFT;
795 		mask = PD_TIM_MASK;
796 		break;
797 	case EMIF_LP_MODE_DISABLE:
798 	default:
799 		mask = 0;
800 		shift = 0;
801 		break;
802 	}
803 	/* Round to maximum in case of overflow, BUT warn! */
804 	if (lpmode != EMIF_LP_MODE_DISABLE && timeout > mask >> shift) {
805 		pr_err("TIMEOUT Overflow - lpmode=%d perf=%d pwr=%d freq=%d\n",
806 		       lpmode,
807 		       timeout_perf,
808 		       timeout_pwr,
809 		       freq_threshold);
810 		WARN(1, "timeout=0x%02x greater than 0x%02x. Using max\n",
811 		     timeout, mask >> shift);
812 		timeout = mask >> shift;
813 	}
814 
815 	/* Setup required timing */
816 	pwr_mgmt_ctrl = (timeout << shift) & mask;
817 	/* setup a default mask for rest of the modes */
818 	pwr_mgmt_ctrl |= (SR_TIM_MASK | CS_TIM_MASK | PD_TIM_MASK) &
819 			  ~mask;
820 
821 	/* No CS_TIM in EMIF_4D5 */
822 	if (ip_rev == EMIF_4D5)
823 		pwr_mgmt_ctrl &= ~CS_TIM_MASK;
824 
825 	pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
826 
827 	return pwr_mgmt_ctrl;
828 }
829 
830 /*
831  * Get the temperature level of the EMIF instance:
832  * Reads the MR4 register of attached SDRAM parts to find out the temperature
833  * level. If there are two parts attached(one on each CS), then the temperature
834  * level for the EMIF instance is the higher of the two temperatures.
835  */
836 static void get_temperature_level(struct emif_data *emif)
837 {
838 	u32		temp, temperature_level;
839 	void __iomem	*base;
840 
841 	base = emif->base;
842 
843 	/* Read mode register 4 */
844 	writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
845 	temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
846 	temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
847 				MR4_SDRAM_REF_RATE_SHIFT;
848 
849 	if (emif->plat_data->device_info->cs1_used) {
850 		writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
851 		temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
852 		temp = (temp & MR4_SDRAM_REF_RATE_MASK)
853 				>> MR4_SDRAM_REF_RATE_SHIFT;
854 		temperature_level = max(temp, temperature_level);
855 	}
856 
857 	/* treat everything less than nominal(3) in MR4 as nominal */
858 	if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
859 		temperature_level = SDRAM_TEMP_NOMINAL;
860 
861 	/* if we get reserved value in MR4 persist with the existing value */
862 	if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
863 		emif->temperature_level = temperature_level;
864 }
865 
866 /*
867  * Program EMIF shadow registers that are not dependent on temperature
868  * or voltage
869  */
870 static void setup_registers(struct emif_data *emif, struct emif_regs *regs)
871 {
872 	void __iomem	*base = emif->base;
873 
874 	writel(regs->sdram_tim2_shdw, base + EMIF_SDRAM_TIMING_2_SHDW);
875 	writel(regs->phy_ctrl_1_shdw, base + EMIF_DDR_PHY_CTRL_1_SHDW);
876 	writel(regs->pwr_mgmt_ctrl_shdw,
877 	       base + EMIF_POWER_MANAGEMENT_CTRL_SHDW);
878 
879 	/* Settings specific for EMIF4D5 */
880 	if (emif->plat_data->ip_rev != EMIF_4D5)
881 		return;
882 	writel(regs->ext_phy_ctrl_2_shdw, base + EMIF_EXT_PHY_CTRL_2_SHDW);
883 	writel(regs->ext_phy_ctrl_3_shdw, base + EMIF_EXT_PHY_CTRL_3_SHDW);
884 	writel(regs->ext_phy_ctrl_4_shdw, base + EMIF_EXT_PHY_CTRL_4_SHDW);
885 }
886 
887 /*
888  * When voltage ramps dll calibration and forced read idle should
889  * happen more often
890  */
891 static void setup_volt_sensitive_regs(struct emif_data *emif,
892 		struct emif_regs *regs, u32 volt_state)
893 {
894 	u32		calib_ctrl;
895 	void __iomem	*base = emif->base;
896 
897 	/*
898 	 * EMIF_READ_IDLE_CTRL in EMIF4D refers to the same register as
899 	 * EMIF_DLL_CALIB_CTRL in EMIF4D5 and dll_calib_ctrl_shadow_*
900 	 * is an alias of the respective read_idle_ctrl_shdw_* (members of
901 	 * a union). So, the below code takes care of both cases
902 	 */
903 	if (volt_state == DDR_VOLTAGE_RAMPING)
904 		calib_ctrl = regs->dll_calib_ctrl_shdw_volt_ramp;
905 	else
906 		calib_ctrl = regs->dll_calib_ctrl_shdw_normal;
907 
908 	writel(calib_ctrl, base + EMIF_DLL_CALIB_CTRL_SHDW);
909 }
910 
911 /*
912  * setup_temperature_sensitive_regs() - set the timings for temperature
913  * sensitive registers. This happens once at initialisation time based
914  * on the temperature at boot time and subsequently based on the temperature
915  * alert interrupt. Temperature alert can happen when the temperature
916  * increases or drops. So this function can have the effect of either
917  * derating the timings or going back to nominal values.
918  */
919 static void setup_temperature_sensitive_regs(struct emif_data *emif,
920 		struct emif_regs *regs)
921 {
922 	u32		tim1, tim3, ref_ctrl, type;
923 	void __iomem	*base = emif->base;
924 	u32		temperature;
925 
926 	type = emif->plat_data->device_info->type;
927 
928 	tim1 = regs->sdram_tim1_shdw;
929 	tim3 = regs->sdram_tim3_shdw;
930 	ref_ctrl = regs->ref_ctrl_shdw;
931 
932 	/* No de-rating for non-lpddr2 devices */
933 	if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
934 		goto out;
935 
936 	temperature = emif->temperature_level;
937 	if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
938 		ref_ctrl = regs->ref_ctrl_shdw_derated;
939 	} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
940 		tim1 = regs->sdram_tim1_shdw_derated;
941 		tim3 = regs->sdram_tim3_shdw_derated;
942 		ref_ctrl = regs->ref_ctrl_shdw_derated;
943 	}
944 
945 out:
946 	writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
947 	writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
948 	writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
949 }
950 
951 static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
952 {
953 	u32		old_temp_level;
954 	irqreturn_t	ret = IRQ_HANDLED;
955 	struct emif_custom_configs *custom_configs;
956 
957 	spin_lock_irqsave(&emif_lock, irq_state);
958 	old_temp_level = emif->temperature_level;
959 	get_temperature_level(emif);
960 
961 	if (unlikely(emif->temperature_level == old_temp_level)) {
962 		goto out;
963 	} else if (!emif->curr_regs) {
964 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
965 		goto out;
966 	}
967 
968 	custom_configs = emif->plat_data->custom_configs;
969 
970 	/*
971 	 * IF we detect higher than "nominal rating" from DDR sensor
972 	 * on an unsupported DDR part, shutdown system
973 	 */
974 	if (custom_configs && !(custom_configs->mask &
975 				EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART)) {
976 		if (emif->temperature_level >= SDRAM_TEMP_HIGH_DERATE_REFRESH) {
977 			dev_err(emif->dev,
978 				"%s:NOT Extended temperature capable memory."
979 				"Converting MR4=0x%02x as shutdown event\n",
980 				__func__, emif->temperature_level);
981 			/*
982 			 * Temperature far too high - do kernel_power_off()
983 			 * from thread context
984 			 */
985 			emif->temperature_level = SDRAM_TEMP_VERY_HIGH_SHUTDOWN;
986 			ret = IRQ_WAKE_THREAD;
987 			goto out;
988 		}
989 	}
990 
991 	if (emif->temperature_level < old_temp_level ||
992 		emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
993 		/*
994 		 * Temperature coming down - defer handling to thread OR
995 		 * Temperature far too high - do kernel_power_off() from
996 		 * thread context
997 		 */
998 		ret = IRQ_WAKE_THREAD;
999 	} else {
1000 		/* Temperature is going up - handle immediately */
1001 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
1002 		do_freq_update();
1003 	}
1004 
1005 out:
1006 	spin_unlock_irqrestore(&emif_lock, irq_state);
1007 	return ret;
1008 }
1009 
1010 static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
1011 {
1012 	u32			interrupts;
1013 	struct emif_data	*emif = dev_id;
1014 	void __iomem		*base = emif->base;
1015 	struct device		*dev = emif->dev;
1016 	irqreturn_t		ret = IRQ_HANDLED;
1017 
1018 	/* Save the status and clear it */
1019 	interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1020 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1021 
1022 	/*
1023 	 * Handle temperature alert
1024 	 * Temperature alert should be same for all ports
1025 	 * So, it's enough to process it only for one of the ports
1026 	 */
1027 	if (interrupts & TA_SYS_MASK)
1028 		ret = handle_temp_alert(base, emif);
1029 
1030 	if (interrupts & ERR_SYS_MASK)
1031 		dev_err(dev, "Access error from SYS port - %x\n", interrupts);
1032 
1033 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1034 		/* Save the status and clear it */
1035 		interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
1036 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
1037 
1038 		if (interrupts & ERR_LL_MASK)
1039 			dev_err(dev, "Access error from LL port - %x\n",
1040 				interrupts);
1041 	}
1042 
1043 	return ret;
1044 }
1045 
1046 static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
1047 {
1048 	struct emif_data	*emif = dev_id;
1049 
1050 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
1051 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1052 
1053 		/* If we have Power OFF ability, use it, else try restarting */
1054 		if (pm_power_off) {
1055 			kernel_power_off();
1056 		} else {
1057 			WARN(1, "FIXME: NO pm_power_off!!! trying restart\n");
1058 			kernel_restart("SDRAM Over-temp Emergency restart");
1059 		}
1060 		return IRQ_HANDLED;
1061 	}
1062 
1063 	spin_lock_irqsave(&emif_lock, irq_state);
1064 
1065 	if (emif->curr_regs) {
1066 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
1067 		do_freq_update();
1068 	} else {
1069 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
1070 	}
1071 
1072 	spin_unlock_irqrestore(&emif_lock, irq_state);
1073 
1074 	return IRQ_HANDLED;
1075 }
1076 
1077 static void clear_all_interrupts(struct emif_data *emif)
1078 {
1079 	void __iomem	*base = emif->base;
1080 
1081 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
1082 		base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1083 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1084 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
1085 			base + EMIF_LL_OCP_INTERRUPT_STATUS);
1086 }
1087 
1088 static void disable_and_clear_all_interrupts(struct emif_data *emif)
1089 {
1090 	void __iomem		*base = emif->base;
1091 
1092 	/* Disable all interrupts */
1093 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
1094 		base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
1095 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1096 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
1097 			base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
1098 
1099 	/* Clear all interrupts */
1100 	clear_all_interrupts(emif);
1101 }
1102 
1103 static int __init_or_module setup_interrupts(struct emif_data *emif, u32 irq)
1104 {
1105 	u32		interrupts, type;
1106 	void __iomem	*base = emif->base;
1107 
1108 	type = emif->plat_data->device_info->type;
1109 
1110 	clear_all_interrupts(emif);
1111 
1112 	/* Enable interrupts for SYS interface */
1113 	interrupts = EN_ERR_SYS_MASK;
1114 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
1115 		interrupts |= EN_TA_SYS_MASK;
1116 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
1117 
1118 	/* Enable interrupts for LL interface */
1119 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1120 		/* TA need not be enabled for LL */
1121 		interrupts = EN_ERR_LL_MASK;
1122 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
1123 	}
1124 
1125 	/* setup IRQ handlers */
1126 	return devm_request_threaded_irq(emif->dev, irq,
1127 				    emif_interrupt_handler,
1128 				    emif_threaded_isr,
1129 				    0, dev_name(emif->dev),
1130 				    emif);
1131 
1132 }
1133 
1134 static void __init_or_module emif_onetime_settings(struct emif_data *emif)
1135 {
1136 	u32				pwr_mgmt_ctrl, zq, temp_alert_cfg;
1137 	void __iomem			*base = emif->base;
1138 	const struct lpddr2_addressing	*addressing;
1139 	const struct ddr_device_info	*device_info;
1140 
1141 	device_info = emif->plat_data->device_info;
1142 	addressing = get_addressing_table(device_info);
1143 
1144 	/*
1145 	 * Init power management settings
1146 	 * We don't know the frequency yet. Use a high frequency
1147 	 * value for a conservative timeout setting
1148 	 */
1149 	pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
1150 			emif->plat_data->ip_rev);
1151 	emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
1152 	writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
1153 
1154 	/* Init ZQ calibration settings */
1155 	zq = get_zq_config_reg(addressing, device_info->cs1_used,
1156 		device_info->cal_resistors_per_cs);
1157 	writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
1158 
1159 	/* Check temperature level temperature level*/
1160 	get_temperature_level(emif);
1161 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
1162 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1163 
1164 	/* Init temperature polling */
1165 	temp_alert_cfg = get_temp_alert_config(addressing,
1166 		emif->plat_data->custom_configs, device_info->cs1_used,
1167 		device_info->io_width, get_emif_bus_width(emif));
1168 	writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
1169 
1170 	/*
1171 	 * Program external PHY control registers that are not frequency
1172 	 * dependent
1173 	 */
1174 	if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
1175 		return;
1176 	writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
1177 	writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
1178 	writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
1179 	writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
1180 	writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
1181 	writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
1182 	writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
1183 	writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
1184 	writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
1185 	writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
1186 	writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
1187 	writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
1188 	writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
1189 	writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
1190 	writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
1191 	writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
1192 	writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
1193 	writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
1194 	writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
1195 	writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
1196 	writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
1197 }
1198 
1199 static void get_default_timings(struct emif_data *emif)
1200 {
1201 	struct emif_platform_data *pd = emif->plat_data;
1202 
1203 	pd->timings		= lpddr2_jedec_timings;
1204 	pd->timings_arr_size	= ARRAY_SIZE(lpddr2_jedec_timings);
1205 
1206 	dev_warn(emif->dev, "%s: using default timings\n", __func__);
1207 }
1208 
1209 static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
1210 		u32 ip_rev, struct device *dev)
1211 {
1212 	int valid;
1213 
1214 	valid = (type == DDR_TYPE_LPDDR2_S4 ||
1215 			type == DDR_TYPE_LPDDR2_S2)
1216 		&& (density >= DDR_DENSITY_64Mb
1217 			&& density <= DDR_DENSITY_8Gb)
1218 		&& (io_width >= DDR_IO_WIDTH_8
1219 			&& io_width <= DDR_IO_WIDTH_32);
1220 
1221 	/* Combinations of EMIF and PHY revisions that we support today */
1222 	switch (ip_rev) {
1223 	case EMIF_4D:
1224 		valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
1225 		break;
1226 	case EMIF_4D5:
1227 		valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
1228 		break;
1229 	default:
1230 		valid = 0;
1231 	}
1232 
1233 	if (!valid)
1234 		dev_err(dev, "%s: invalid DDR details\n", __func__);
1235 	return valid;
1236 }
1237 
1238 static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
1239 		struct device *dev)
1240 {
1241 	int valid = 1;
1242 
1243 	if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
1244 		(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
1245 		valid = cust_cfgs->lpmode_freq_threshold &&
1246 			cust_cfgs->lpmode_timeout_performance &&
1247 			cust_cfgs->lpmode_timeout_power;
1248 
1249 	if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
1250 		valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
1251 
1252 	if (!valid)
1253 		dev_warn(dev, "%s: invalid custom configs\n", __func__);
1254 
1255 	return valid;
1256 }
1257 
1258 #if defined(CONFIG_OF)
1259 static void __init_or_module of_get_custom_configs(struct device_node *np_emif,
1260 		struct emif_data *emif)
1261 {
1262 	struct emif_custom_configs	*cust_cfgs = NULL;
1263 	int				len;
1264 	const __be32			*lpmode, *poll_intvl;
1265 
1266 	lpmode = of_get_property(np_emif, "low-power-mode", &len);
1267 	poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
1268 
1269 	if (lpmode || poll_intvl)
1270 		cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
1271 			GFP_KERNEL);
1272 
1273 	if (!cust_cfgs)
1274 		return;
1275 
1276 	if (lpmode) {
1277 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
1278 		cust_cfgs->lpmode = be32_to_cpup(lpmode);
1279 		of_property_read_u32(np_emif,
1280 				"low-power-mode-timeout-performance",
1281 				&cust_cfgs->lpmode_timeout_performance);
1282 		of_property_read_u32(np_emif,
1283 				"low-power-mode-timeout-power",
1284 				&cust_cfgs->lpmode_timeout_power);
1285 		of_property_read_u32(np_emif,
1286 				"low-power-mode-freq-threshold",
1287 				&cust_cfgs->lpmode_freq_threshold);
1288 	}
1289 
1290 	if (poll_intvl) {
1291 		cust_cfgs->mask |=
1292 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
1293 		cust_cfgs->temp_alert_poll_interval_ms =
1294 						be32_to_cpup(poll_intvl);
1295 	}
1296 
1297 	if (of_find_property(np_emif, "extended-temp-part", &len))
1298 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART;
1299 
1300 	if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
1301 		devm_kfree(emif->dev, cust_cfgs);
1302 		return;
1303 	}
1304 
1305 	emif->plat_data->custom_configs = cust_cfgs;
1306 }
1307 
1308 static void __init_or_module of_get_ddr_info(struct device_node *np_emif,
1309 		struct device_node *np_ddr,
1310 		struct ddr_device_info *dev_info)
1311 {
1312 	u32 density = 0, io_width = 0;
1313 	int len;
1314 
1315 	if (of_find_property(np_emif, "cs1-used", &len))
1316 		dev_info->cs1_used = true;
1317 
1318 	if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
1319 		dev_info->cal_resistors_per_cs = true;
1320 
1321 	if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s4"))
1322 		dev_info->type = DDR_TYPE_LPDDR2_S4;
1323 	else if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s2"))
1324 		dev_info->type = DDR_TYPE_LPDDR2_S2;
1325 
1326 	of_property_read_u32(np_ddr, "density", &density);
1327 	of_property_read_u32(np_ddr, "io-width", &io_width);
1328 
1329 	/* Convert from density in Mb to the density encoding in jedc_ddr.h */
1330 	if (density & (density - 1))
1331 		dev_info->density = 0;
1332 	else
1333 		dev_info->density = __fls(density) - 5;
1334 
1335 	/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
1336 	if (io_width & (io_width - 1))
1337 		dev_info->io_width = 0;
1338 	else
1339 		dev_info->io_width = __fls(io_width) - 1;
1340 }
1341 
1342 static struct emif_data * __init_or_module of_get_memory_device_details(
1343 		struct device_node *np_emif, struct device *dev)
1344 {
1345 	struct emif_data		*emif = NULL;
1346 	struct ddr_device_info		*dev_info = NULL;
1347 	struct emif_platform_data	*pd = NULL;
1348 	struct device_node		*np_ddr;
1349 	int				len;
1350 
1351 	np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
1352 	if (!np_ddr)
1353 		goto error;
1354 	emif	= devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
1355 	pd	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1356 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1357 
1358 	if (!emif || !pd || !dev_info) {
1359 		dev_err(dev, "%s: Out of memory!!\n",
1360 			__func__);
1361 		goto error;
1362 	}
1363 
1364 	emif->plat_data		= pd;
1365 	pd->device_info		= dev_info;
1366 	emif->dev		= dev;
1367 	emif->np_ddr		= np_ddr;
1368 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1369 
1370 	if (of_device_is_compatible(np_emif, "ti,emif-4d"))
1371 		emif->plat_data->ip_rev = EMIF_4D;
1372 	else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
1373 		emif->plat_data->ip_rev = EMIF_4D5;
1374 
1375 	of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
1376 
1377 	if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
1378 		pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
1379 
1380 	of_get_ddr_info(np_emif, np_ddr, dev_info);
1381 	if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
1382 			pd->device_info->io_width, pd->phy_type, pd->ip_rev,
1383 			emif->dev)) {
1384 		dev_err(dev, "%s: invalid device data!!\n", __func__);
1385 		goto error;
1386 	}
1387 	/*
1388 	 * For EMIF instances other than EMIF1 see if the devices connected
1389 	 * are exactly same as on EMIF1(which is typically the case). If so,
1390 	 * mark it as a duplicate of EMIF1. This will save some memory and
1391 	 * computation.
1392 	 */
1393 	if (emif1 && emif1->np_ddr == np_ddr) {
1394 		emif->duplicate = true;
1395 		goto out;
1396 	} else if (emif1) {
1397 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1398 			__func__);
1399 	}
1400 
1401 	of_get_custom_configs(np_emif, emif);
1402 	emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
1403 					emif->plat_data->device_info->type,
1404 					&emif->plat_data->timings_arr_size);
1405 
1406 	emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
1407 	goto out;
1408 
1409 error:
1410 	return NULL;
1411 out:
1412 	return emif;
1413 }
1414 
1415 #else
1416 
1417 static struct emif_data * __init_or_module of_get_memory_device_details(
1418 		struct device_node *np_emif, struct device *dev)
1419 {
1420 	return NULL;
1421 }
1422 #endif
1423 
1424 static struct emif_data *__init_or_module get_device_details(
1425 		struct platform_device *pdev)
1426 {
1427 	u32				size;
1428 	struct emif_data		*emif = NULL;
1429 	struct ddr_device_info		*dev_info;
1430 	struct emif_custom_configs	*cust_cfgs;
1431 	struct emif_platform_data	*pd;
1432 	struct device			*dev;
1433 	void				*temp;
1434 
1435 	pd = pdev->dev.platform_data;
1436 	dev = &pdev->dev;
1437 
1438 	if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
1439 			pd->device_info->density, pd->device_info->io_width,
1440 			pd->phy_type, pd->ip_rev, dev))) {
1441 		dev_err(dev, "%s: invalid device data\n", __func__);
1442 		goto error;
1443 	}
1444 
1445 	emif	= devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
1446 	temp	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1447 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1448 
1449 	if (!emif || !pd || !dev_info) {
1450 		dev_err(dev, "%s:%d: allocation error\n", __func__, __LINE__);
1451 		goto error;
1452 	}
1453 
1454 	memcpy(temp, pd, sizeof(*pd));
1455 	pd = temp;
1456 	memcpy(dev_info, pd->device_info, sizeof(*dev_info));
1457 
1458 	pd->device_info		= dev_info;
1459 	emif->plat_data		= pd;
1460 	emif->dev		= dev;
1461 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1462 
1463 	/*
1464 	 * For EMIF instances other than EMIF1 see if the devices connected
1465 	 * are exactly same as on EMIF1(which is typically the case). If so,
1466 	 * mark it as a duplicate of EMIF1 and skip copying timings data.
1467 	 * This will save some memory and some computation later.
1468 	 */
1469 	emif->duplicate = emif1 && (memcmp(dev_info,
1470 		emif1->plat_data->device_info,
1471 		sizeof(struct ddr_device_info)) == 0);
1472 
1473 	if (emif->duplicate) {
1474 		pd->timings = NULL;
1475 		pd->min_tck = NULL;
1476 		goto out;
1477 	} else if (emif1) {
1478 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1479 			__func__);
1480 	}
1481 
1482 	/*
1483 	 * Copy custom configs - ignore allocation error, if any, as
1484 	 * custom_configs is not very critical
1485 	 */
1486 	cust_cfgs = pd->custom_configs;
1487 	if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
1488 		temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
1489 		if (temp)
1490 			memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
1491 		else
1492 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1493 				__LINE__);
1494 		pd->custom_configs = temp;
1495 	}
1496 
1497 	/*
1498 	 * Copy timings and min-tck values from platform data. If it is not
1499 	 * available or if memory allocation fails, use JEDEC defaults
1500 	 */
1501 	size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
1502 	if (pd->timings) {
1503 		temp = devm_kzalloc(dev, size, GFP_KERNEL);
1504 		if (temp) {
1505 			memcpy(temp, pd->timings, size);
1506 			pd->timings = temp;
1507 		} else {
1508 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1509 				__LINE__);
1510 			get_default_timings(emif);
1511 		}
1512 	} else {
1513 		get_default_timings(emif);
1514 	}
1515 
1516 	if (pd->min_tck) {
1517 		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
1518 		if (temp) {
1519 			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
1520 			pd->min_tck = temp;
1521 		} else {
1522 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1523 				__LINE__);
1524 			pd->min_tck = &lpddr2_jedec_min_tck;
1525 		}
1526 	} else {
1527 		pd->min_tck = &lpddr2_jedec_min_tck;
1528 	}
1529 
1530 out:
1531 	return emif;
1532 
1533 error:
1534 	return NULL;
1535 }
1536 
1537 static int __init_or_module emif_probe(struct platform_device *pdev)
1538 {
1539 	struct emif_data	*emif;
1540 	struct resource		*res;
1541 	int			irq;
1542 
1543 	if (pdev->dev.of_node)
1544 		emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
1545 	else
1546 		emif = get_device_details(pdev);
1547 
1548 	if (!emif) {
1549 		pr_err("%s: error getting device data\n", __func__);
1550 		goto error;
1551 	}
1552 
1553 	list_add(&emif->node, &device_list);
1554 	emif->addressing = get_addressing_table(emif->plat_data->device_info);
1555 
1556 	/* Save pointers to each other in emif and device structures */
1557 	emif->dev = &pdev->dev;
1558 	platform_set_drvdata(pdev, emif);
1559 
1560 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1561 	emif->base = devm_ioremap_resource(emif->dev, res);
1562 	if (IS_ERR(emif->base))
1563 		goto error;
1564 
1565 	irq = platform_get_irq(pdev, 0);
1566 	if (irq < 0) {
1567 		dev_err(emif->dev, "%s: error getting IRQ resource - %d\n",
1568 			__func__, irq);
1569 		goto error;
1570 	}
1571 
1572 	emif_onetime_settings(emif);
1573 	emif_debugfs_init(emif);
1574 	disable_and_clear_all_interrupts(emif);
1575 	setup_interrupts(emif, irq);
1576 
1577 	/* One-time actions taken on probing the first device */
1578 	if (!emif1) {
1579 		emif1 = emif;
1580 		spin_lock_init(&emif_lock);
1581 
1582 		/*
1583 		 * TODO: register notifiers for frequency and voltage
1584 		 * change here once the respective frameworks are
1585 		 * available
1586 		 */
1587 	}
1588 
1589 	dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
1590 		__func__, emif->base, irq);
1591 
1592 	return 0;
1593 error:
1594 	return -ENODEV;
1595 }
1596 
1597 static int __exit emif_remove(struct platform_device *pdev)
1598 {
1599 	struct emif_data *emif = platform_get_drvdata(pdev);
1600 
1601 	emif_debugfs_exit(emif);
1602 
1603 	return 0;
1604 }
1605 
1606 static void emif_shutdown(struct platform_device *pdev)
1607 {
1608 	struct emif_data	*emif = platform_get_drvdata(pdev);
1609 
1610 	disable_and_clear_all_interrupts(emif);
1611 }
1612 
1613 static int get_emif_reg_values(struct emif_data *emif, u32 freq,
1614 		struct emif_regs *regs)
1615 {
1616 	u32				cs1_used, ip_rev, phy_type;
1617 	u32				cl, type;
1618 	const struct lpddr2_timings	*timings;
1619 	const struct lpddr2_min_tck	*min_tck;
1620 	const struct ddr_device_info	*device_info;
1621 	const struct lpddr2_addressing	*addressing;
1622 	struct emif_data		*emif_for_calc;
1623 	struct device			*dev;
1624 	const struct emif_custom_configs *custom_configs;
1625 
1626 	dev = emif->dev;
1627 	/*
1628 	 * If the devices on this EMIF instance is duplicate of EMIF1,
1629 	 * use EMIF1 details for the calculation
1630 	 */
1631 	emif_for_calc	= emif->duplicate ? emif1 : emif;
1632 	timings		= get_timings_table(emif_for_calc, freq);
1633 	addressing	= emif_for_calc->addressing;
1634 	if (!timings || !addressing) {
1635 		dev_err(dev, "%s: not enough data available for %dHz",
1636 			__func__, freq);
1637 		return -1;
1638 	}
1639 
1640 	device_info	= emif_for_calc->plat_data->device_info;
1641 	type		= device_info->type;
1642 	cs1_used	= device_info->cs1_used;
1643 	ip_rev		= emif_for_calc->plat_data->ip_rev;
1644 	phy_type	= emif_for_calc->plat_data->phy_type;
1645 
1646 	min_tck		= emif_for_calc->plat_data->min_tck;
1647 	custom_configs	= emif_for_calc->plat_data->custom_configs;
1648 
1649 	set_ddr_clk_period(freq);
1650 
1651 	regs->ref_ctrl_shdw = get_sdram_ref_ctrl_shdw(freq, addressing);
1652 	regs->sdram_tim1_shdw = get_sdram_tim_1_shdw(timings, min_tck,
1653 			addressing);
1654 	regs->sdram_tim2_shdw = get_sdram_tim_2_shdw(timings, min_tck,
1655 			addressing, type);
1656 	regs->sdram_tim3_shdw = get_sdram_tim_3_shdw(timings, min_tck,
1657 		addressing, type, ip_rev, EMIF_NORMAL_TIMINGS);
1658 
1659 	cl = get_cl(emif);
1660 
1661 	if (phy_type == EMIF_PHY_TYPE_ATTILAPHY && ip_rev == EMIF_4D) {
1662 		regs->phy_ctrl_1_shdw = get_ddr_phy_ctrl_1_attilaphy_4d(
1663 			timings, freq, cl);
1664 	} else if (phy_type == EMIF_PHY_TYPE_INTELLIPHY && ip_rev == EMIF_4D5) {
1665 		regs->phy_ctrl_1_shdw = get_phy_ctrl_1_intelliphy_4d5(freq, cl);
1666 		regs->ext_phy_ctrl_2_shdw = get_ext_phy_ctrl_2_intelliphy_4d5();
1667 		regs->ext_phy_ctrl_3_shdw = get_ext_phy_ctrl_3_intelliphy_4d5();
1668 		regs->ext_phy_ctrl_4_shdw = get_ext_phy_ctrl_4_intelliphy_4d5();
1669 	} else {
1670 		return -1;
1671 	}
1672 
1673 	/* Only timeout values in pwr_mgmt_ctrl_shdw register */
1674 	regs->pwr_mgmt_ctrl_shdw =
1675 		get_pwr_mgmt_ctrl(freq, emif_for_calc, ip_rev) &
1676 		(CS_TIM_MASK | SR_TIM_MASK | PD_TIM_MASK);
1677 
1678 	if (ip_rev & EMIF_4D) {
1679 		regs->read_idle_ctrl_shdw_normal =
1680 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_STABLE);
1681 
1682 		regs->read_idle_ctrl_shdw_volt_ramp =
1683 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1684 	} else if (ip_rev & EMIF_4D5) {
1685 		regs->dll_calib_ctrl_shdw_normal =
1686 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_STABLE);
1687 
1688 		regs->dll_calib_ctrl_shdw_volt_ramp =
1689 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1690 	}
1691 
1692 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
1693 		regs->ref_ctrl_shdw_derated = get_sdram_ref_ctrl_shdw(freq / 4,
1694 			addressing);
1695 
1696 		regs->sdram_tim1_shdw_derated =
1697 			get_sdram_tim_1_shdw_derated(timings, min_tck,
1698 				addressing);
1699 
1700 		regs->sdram_tim3_shdw_derated = get_sdram_tim_3_shdw(timings,
1701 			min_tck, addressing, type, ip_rev,
1702 			EMIF_DERATED_TIMINGS);
1703 	}
1704 
1705 	regs->freq = freq;
1706 
1707 	return 0;
1708 }
1709 
1710 /*
1711  * get_regs() - gets the cached emif_regs structure for a given EMIF instance
1712  * given frequency(freq):
1713  *
1714  * As an optimisation, every EMIF instance other than EMIF1 shares the
1715  * register cache with EMIF1 if the devices connected on this instance
1716  * are same as that on EMIF1(indicated by the duplicate flag)
1717  *
1718  * If we do not have an entry corresponding to the frequency given, we
1719  * allocate a new entry and calculate the values
1720  *
1721  * Upon finding the right reg dump, save it in curr_regs. It can be
1722  * directly used for thermal de-rating and voltage ramping changes.
1723  */
1724 static struct emif_regs *get_regs(struct emif_data *emif, u32 freq)
1725 {
1726 	int			i;
1727 	struct emif_regs	**regs_cache;
1728 	struct emif_regs	*regs = NULL;
1729 	struct device		*dev;
1730 
1731 	dev = emif->dev;
1732 	if (emif->curr_regs && emif->curr_regs->freq == freq) {
1733 		dev_dbg(dev, "%s: using curr_regs - %u Hz", __func__, freq);
1734 		return emif->curr_regs;
1735 	}
1736 
1737 	if (emif->duplicate)
1738 		regs_cache = emif1->regs_cache;
1739 	else
1740 		regs_cache = emif->regs_cache;
1741 
1742 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
1743 		if (regs_cache[i]->freq == freq) {
1744 			regs = regs_cache[i];
1745 			dev_dbg(dev,
1746 				"%s: reg dump found in reg cache for %u Hz\n",
1747 				__func__, freq);
1748 			break;
1749 		}
1750 	}
1751 
1752 	/*
1753 	 * If we don't have an entry for this frequency in the cache create one
1754 	 * and calculate the values
1755 	 */
1756 	if (!regs) {
1757 		regs = devm_kzalloc(emif->dev, sizeof(*regs), GFP_ATOMIC);
1758 		if (!regs)
1759 			return NULL;
1760 
1761 		if (get_emif_reg_values(emif, freq, regs)) {
1762 			devm_kfree(emif->dev, regs);
1763 			return NULL;
1764 		}
1765 
1766 		/*
1767 		 * Now look for an un-used entry in the cache and save the
1768 		 * newly created struct. If there are no free entries
1769 		 * over-write the last entry
1770 		 */
1771 		for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++)
1772 			;
1773 
1774 		if (i >= EMIF_MAX_NUM_FREQUENCIES) {
1775 			dev_warn(dev, "%s: regs_cache full - reusing a slot!!\n",
1776 				__func__);
1777 			i = EMIF_MAX_NUM_FREQUENCIES - 1;
1778 			devm_kfree(emif->dev, regs_cache[i]);
1779 		}
1780 		regs_cache[i] = regs;
1781 	}
1782 
1783 	return regs;
1784 }
1785 
1786 static void do_volt_notify_handling(struct emif_data *emif, u32 volt_state)
1787 {
1788 	dev_dbg(emif->dev, "%s: voltage notification : %d", __func__,
1789 		volt_state);
1790 
1791 	if (!emif->curr_regs) {
1792 		dev_err(emif->dev,
1793 			"%s: volt-notify before registers are ready: %d\n",
1794 			__func__, volt_state);
1795 		return;
1796 	}
1797 
1798 	setup_volt_sensitive_regs(emif, emif->curr_regs, volt_state);
1799 }
1800 
1801 /*
1802  * TODO: voltage notify handling should be hooked up to
1803  * regulator framework as soon as the necessary support
1804  * is available in mainline kernel. This function is un-used
1805  * right now.
1806  */
1807 static void __attribute__((unused)) volt_notify_handling(u32 volt_state)
1808 {
1809 	struct emif_data *emif;
1810 
1811 	spin_lock_irqsave(&emif_lock, irq_state);
1812 
1813 	list_for_each_entry(emif, &device_list, node)
1814 		do_volt_notify_handling(emif, volt_state);
1815 	do_freq_update();
1816 
1817 	spin_unlock_irqrestore(&emif_lock, irq_state);
1818 }
1819 
1820 static void do_freq_pre_notify_handling(struct emif_data *emif, u32 new_freq)
1821 {
1822 	struct emif_regs *regs;
1823 
1824 	regs = get_regs(emif, new_freq);
1825 	if (!regs)
1826 		return;
1827 
1828 	emif->curr_regs = regs;
1829 
1830 	/*
1831 	 * Update the shadow registers:
1832 	 * Temperature and voltage-ramp sensitive settings are also configured
1833 	 * in terms of DDR cycles. So, we need to update them too when there
1834 	 * is a freq change
1835 	 */
1836 	dev_dbg(emif->dev, "%s: setting up shadow registers for %uHz",
1837 		__func__, new_freq);
1838 	setup_registers(emif, regs);
1839 	setup_temperature_sensitive_regs(emif, regs);
1840 	setup_volt_sensitive_regs(emif, regs, DDR_VOLTAGE_STABLE);
1841 
1842 	/*
1843 	 * Part of workaround for errata i728. See do_freq_update()
1844 	 * for more details
1845 	 */
1846 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1847 		set_lpmode(emif, EMIF_LP_MODE_DISABLE);
1848 }
1849 
1850 /*
1851  * TODO: frequency notify handling should be hooked up to
1852  * clock framework as soon as the necessary support is
1853  * available in mainline kernel. This function is un-used
1854  * right now.
1855  */
1856 static void __attribute__((unused)) freq_pre_notify_handling(u32 new_freq)
1857 {
1858 	struct emif_data *emif;
1859 
1860 	/*
1861 	 * NOTE: we are taking the spin-lock here and releases it
1862 	 * only in post-notifier. This doesn't look good and
1863 	 * Sparse complains about it, but this seems to be
1864 	 * un-avoidable. We need to lock a sequence of events
1865 	 * that is split between EMIF and clock framework.
1866 	 *
1867 	 * 1. EMIF driver updates EMIF timings in shadow registers in the
1868 	 *    frequency pre-notify callback from clock framework
1869 	 * 2. clock framework sets up the registers for the new frequency
1870 	 * 3. clock framework initiates a hw-sequence that updates
1871 	 *    the frequency EMIF timings synchronously.
1872 	 *
1873 	 * All these 3 steps should be performed as an atomic operation
1874 	 * vis-a-vis similar sequence in the EMIF interrupt handler
1875 	 * for temperature events. Otherwise, there could be race
1876 	 * conditions that could result in incorrect EMIF timings for
1877 	 * a given frequency
1878 	 */
1879 	spin_lock_irqsave(&emif_lock, irq_state);
1880 
1881 	list_for_each_entry(emif, &device_list, node)
1882 		do_freq_pre_notify_handling(emif, new_freq);
1883 }
1884 
1885 static void do_freq_post_notify_handling(struct emif_data *emif)
1886 {
1887 	/*
1888 	 * Part of workaround for errata i728. See do_freq_update()
1889 	 * for more details
1890 	 */
1891 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1892 		set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
1893 }
1894 
1895 /*
1896  * TODO: frequency notify handling should be hooked up to
1897  * clock framework as soon as the necessary support is
1898  * available in mainline kernel. This function is un-used
1899  * right now.
1900  */
1901 static void __attribute__((unused)) freq_post_notify_handling(void)
1902 {
1903 	struct emif_data *emif;
1904 
1905 	list_for_each_entry(emif, &device_list, node)
1906 		do_freq_post_notify_handling(emif);
1907 
1908 	/*
1909 	 * Lock is done in pre-notify handler. See freq_pre_notify_handling()
1910 	 * for more details
1911 	 */
1912 	spin_unlock_irqrestore(&emif_lock, irq_state);
1913 }
1914 
1915 #if defined(CONFIG_OF)
1916 static const struct of_device_id emif_of_match[] = {
1917 		{ .compatible = "ti,emif-4d" },
1918 		{ .compatible = "ti,emif-4d5" },
1919 		{},
1920 };
1921 MODULE_DEVICE_TABLE(of, emif_of_match);
1922 #endif
1923 
1924 static struct platform_driver emif_driver = {
1925 	.remove		= __exit_p(emif_remove),
1926 	.shutdown	= emif_shutdown,
1927 	.driver = {
1928 		.name = "emif",
1929 		.of_match_table = of_match_ptr(emif_of_match),
1930 	},
1931 };
1932 
1933 module_platform_driver_probe(emif_driver, emif_probe);
1934 
1935 MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
1936 MODULE_LICENSE("GPL");
1937 MODULE_ALIAS("platform:emif");
1938 MODULE_AUTHOR("Texas Instruments Inc");
1939