xref: /openbmc/linux/drivers/memory/emif.c (revision 4e95bc26)
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 #include <memory/jedec_ddr.h>
27 #include "emif.h"
28 #include "of_memory.h"
29 
30 /**
31  * struct emif_data - Per device static data for driver's use
32  * @duplicate:			Whether the DDR devices attached to this EMIF
33  *				instance are exactly same as that on EMIF1. In
34  *				this case we can save some memory and processing
35  * @temperature_level:		Maximum temperature of LPDDR2 devices attached
36  *				to this EMIF - read from MR4 register. If there
37  *				are two devices attached to this EMIF, this
38  *				value is the maximum of the two temperature
39  *				levels.
40  * @node:			node in the device list
41  * @base:			base address of memory-mapped IO registers.
42  * @dev:			device pointer.
43  * @addressing			table with addressing information from the spec
44  * @regs_cache:			An array of 'struct emif_regs' that stores
45  *				calculated register values for different
46  *				frequencies, to avoid re-calculating them on
47  *				each DVFS transition.
48  * @curr_regs:			The set of register values used in the last
49  *				frequency change (i.e. corresponding to the
50  *				frequency in effect at the moment)
51  * @plat_data:			Pointer to saved platform data.
52  * @debugfs_root:		dentry to the root folder for EMIF in debugfs
53  * @np_ddr:			Pointer to ddr device tree node
54  */
55 struct emif_data {
56 	u8				duplicate;
57 	u8				temperature_level;
58 	u8				lpmode;
59 	struct list_head		node;
60 	unsigned long			irq_state;
61 	void __iomem			*base;
62 	struct device			*dev;
63 	const struct lpddr2_addressing	*addressing;
64 	struct emif_regs		*regs_cache[EMIF_MAX_NUM_FREQUENCIES];
65 	struct emif_regs		*curr_regs;
66 	struct emif_platform_data	*plat_data;
67 	struct dentry			*debugfs_root;
68 	struct device_node		*np_ddr;
69 };
70 
71 static struct emif_data *emif1;
72 static spinlock_t	emif_lock;
73 static unsigned long	irq_state;
74 static u32		t_ck; /* DDR clock period in ps */
75 static LIST_HEAD(device_list);
76 
77 #ifdef CONFIG_DEBUG_FS
78 static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
79 	struct emif_regs *regs)
80 {
81 	u32 type = emif->plat_data->device_info->type;
82 	u32 ip_rev = emif->plat_data->ip_rev;
83 
84 	seq_printf(s, "EMIF register cache dump for %dMHz\n",
85 		regs->freq/1000000);
86 
87 	seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
88 	seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
89 	seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
90 	seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
91 
92 	if (ip_rev == EMIF_4D) {
93 		seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
94 			regs->read_idle_ctrl_shdw_normal);
95 		seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
96 			regs->read_idle_ctrl_shdw_volt_ramp);
97 	} else if (ip_rev == EMIF_4D5) {
98 		seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
99 			regs->dll_calib_ctrl_shdw_normal);
100 		seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
101 			regs->dll_calib_ctrl_shdw_volt_ramp);
102 	}
103 
104 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
105 		seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
106 			regs->ref_ctrl_shdw_derated);
107 		seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
108 			regs->sdram_tim1_shdw_derated);
109 		seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
110 			regs->sdram_tim3_shdw_derated);
111 	}
112 }
113 
114 static int emif_regdump_show(struct seq_file *s, void *unused)
115 {
116 	struct emif_data	*emif	= s->private;
117 	struct emif_regs	**regs_cache;
118 	int			i;
119 
120 	if (emif->duplicate)
121 		regs_cache = emif1->regs_cache;
122 	else
123 		regs_cache = emif->regs_cache;
124 
125 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
126 		do_emif_regdump_show(s, emif, regs_cache[i]);
127 		seq_putc(s, '\n');
128 	}
129 
130 	return 0;
131 }
132 
133 static int emif_regdump_open(struct inode *inode, struct file *file)
134 {
135 	return single_open(file, emif_regdump_show, inode->i_private);
136 }
137 
138 static const struct file_operations emif_regdump_fops = {
139 	.open			= emif_regdump_open,
140 	.read			= seq_read,
141 	.release		= single_release,
142 };
143 
144 static int emif_mr4_show(struct seq_file *s, void *unused)
145 {
146 	struct emif_data *emif = s->private;
147 
148 	seq_printf(s, "MR4=%d\n", emif->temperature_level);
149 	return 0;
150 }
151 
152 static int emif_mr4_open(struct inode *inode, struct file *file)
153 {
154 	return single_open(file, emif_mr4_show, inode->i_private);
155 }
156 
157 static const struct file_operations emif_mr4_fops = {
158 	.open			= emif_mr4_open,
159 	.read			= seq_read,
160 	.release		= single_release,
161 };
162 
163 static int __init_or_module emif_debugfs_init(struct emif_data *emif)
164 {
165 	struct dentry	*dentry;
166 	int		ret;
167 
168 	dentry = debugfs_create_dir(dev_name(emif->dev), NULL);
169 	if (!dentry) {
170 		ret = -ENOMEM;
171 		goto err0;
172 	}
173 	emif->debugfs_root = dentry;
174 
175 	dentry = debugfs_create_file("regcache_dump", S_IRUGO,
176 			emif->debugfs_root, emif, &emif_regdump_fops);
177 	if (!dentry) {
178 		ret = -ENOMEM;
179 		goto err1;
180 	}
181 
182 	dentry = debugfs_create_file("mr4", S_IRUGO,
183 			emif->debugfs_root, emif, &emif_mr4_fops);
184 	if (!dentry) {
185 		ret = -ENOMEM;
186 		goto err1;
187 	}
188 
189 	return 0;
190 err1:
191 	debugfs_remove_recursive(emif->debugfs_root);
192 err0:
193 	return ret;
194 }
195 
196 static void __exit emif_debugfs_exit(struct emif_data *emif)
197 {
198 	debugfs_remove_recursive(emif->debugfs_root);
199 	emif->debugfs_root = NULL;
200 }
201 #else
202 static inline int __init_or_module emif_debugfs_init(struct emif_data *emif)
203 {
204 	return 0;
205 }
206 
207 static inline void __exit emif_debugfs_exit(struct emif_data *emif)
208 {
209 }
210 #endif
211 
212 /*
213  * Calculate the period of DDR clock from frequency value
214  */
215 static void set_ddr_clk_period(u32 freq)
216 {
217 	/* Divide 10^12 by frequency to get period in ps */
218 	t_ck = (u32)DIV_ROUND_UP_ULL(1000000000000ull, freq);
219 }
220 
221 /*
222  * Get bus width used by EMIF. Note that this may be different from the
223  * bus width of the DDR devices used. For instance two 16-bit DDR devices
224  * may be connected to a given CS of EMIF. In this case bus width as far
225  * as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
226  */
227 static u32 get_emif_bus_width(struct emif_data *emif)
228 {
229 	u32		width;
230 	void __iomem	*base = emif->base;
231 
232 	width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
233 			>> NARROW_MODE_SHIFT;
234 	width = width == 0 ? 32 : 16;
235 
236 	return width;
237 }
238 
239 /*
240  * Get the CL from SDRAM_CONFIG register
241  */
242 static u32 get_cl(struct emif_data *emif)
243 {
244 	u32		cl;
245 	void __iomem	*base = emif->base;
246 
247 	cl = (readl(base + EMIF_SDRAM_CONFIG) & CL_MASK) >> CL_SHIFT;
248 
249 	return cl;
250 }
251 
252 static void set_lpmode(struct emif_data *emif, u8 lpmode)
253 {
254 	u32 temp;
255 	void __iomem *base = emif->base;
256 
257 	/*
258 	 * Workaround for errata i743 - LPDDR2 Power-Down State is Not
259 	 * Efficient
260 	 *
261 	 * i743 DESCRIPTION:
262 	 * The EMIF supports power-down state for low power. The EMIF
263 	 * automatically puts the SDRAM into power-down after the memory is
264 	 * not accessed for a defined number of cycles and the
265 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set to 0x4.
266 	 * As the EMIF supports automatic output impedance calibration, a ZQ
267 	 * calibration long command is issued every time it exits active
268 	 * power-down and precharge power-down modes. The EMIF waits and
269 	 * blocks any other command during this calibration.
270 	 * The EMIF does not allow selective disabling of ZQ calibration upon
271 	 * exit of power-down mode. Due to very short periods of power-down
272 	 * cycles, ZQ calibration overhead creates bandwidth issues and
273 	 * increases overall system power consumption. On the other hand,
274 	 * issuing ZQ calibration long commands when exiting self-refresh is
275 	 * still required.
276 	 *
277 	 * WORKAROUND
278 	 * Because there is no power consumption benefit of the power-down due
279 	 * to the calibration and there is a performance risk, the guideline
280 	 * is to not allow power-down state and, therefore, to not have set
281 	 * the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field to 0x4.
282 	 */
283 	if ((emif->plat_data->ip_rev == EMIF_4D) &&
284 	    (EMIF_LP_MODE_PWR_DN == lpmode)) {
285 		WARN_ONCE(1,
286 			  "REG_LP_MODE = LP_MODE_PWR_DN(4) is prohibited by"
287 			  "erratum i743 switch to LP_MODE_SELF_REFRESH(2)\n");
288 		/* rollback LP_MODE to Self-refresh mode */
289 		lpmode = EMIF_LP_MODE_SELF_REFRESH;
290 	}
291 
292 	temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
293 	temp &= ~LP_MODE_MASK;
294 	temp |= (lpmode << LP_MODE_SHIFT);
295 	writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
296 }
297 
298 static void do_freq_update(void)
299 {
300 	struct emif_data *emif;
301 
302 	/*
303 	 * Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
304 	 *
305 	 * i728 DESCRIPTION:
306 	 * The EMIF automatically puts the SDRAM into self-refresh mode
307 	 * after the EMIF has not performed accesses during
308 	 * EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
309 	 * and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
310 	 * to 0x2. If during a small window the following three events
311 	 * occur:
312 	 * - The SR_TIMING counter expires
313 	 * - And frequency change is requested
314 	 * - And OCP access is requested
315 	 * Then it causes instable clock on the DDR interface.
316 	 *
317 	 * WORKAROUND
318 	 * To avoid the occurrence of the three events, the workaround
319 	 * is to disable the self-refresh when requesting a frequency
320 	 * change. Before requesting a frequency change the software must
321 	 * program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
322 	 * frequency change has been done, the software can reprogram
323 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
324 	 */
325 	list_for_each_entry(emif, &device_list, node) {
326 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
327 			set_lpmode(emif, EMIF_LP_MODE_DISABLE);
328 	}
329 
330 	/*
331 	 * TODO: Do FREQ_UPDATE here when an API
332 	 * is available for this as part of the new
333 	 * clock framework
334 	 */
335 
336 	list_for_each_entry(emif, &device_list, node) {
337 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
338 			set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
339 	}
340 }
341 
342 /* Find addressing table entry based on the device's type and density */
343 static const struct lpddr2_addressing *get_addressing_table(
344 	const struct ddr_device_info *device_info)
345 {
346 	u32		index, type, density;
347 
348 	type = device_info->type;
349 	density = device_info->density;
350 
351 	switch (type) {
352 	case DDR_TYPE_LPDDR2_S4:
353 		index = density - 1;
354 		break;
355 	case DDR_TYPE_LPDDR2_S2:
356 		switch (density) {
357 		case DDR_DENSITY_1Gb:
358 		case DDR_DENSITY_2Gb:
359 			index = density + 3;
360 			break;
361 		default:
362 			index = density - 1;
363 		}
364 		break;
365 	default:
366 		return NULL;
367 	}
368 
369 	return &lpddr2_jedec_addressing_table[index];
370 }
371 
372 /*
373  * Find the the right timing table from the array of timing
374  * tables of the device using DDR clock frequency
375  */
376 static const struct lpddr2_timings *get_timings_table(struct emif_data *emif,
377 		u32 freq)
378 {
379 	u32				i, min, max, freq_nearest;
380 	const struct lpddr2_timings	*timings = NULL;
381 	const struct lpddr2_timings	*timings_arr = emif->plat_data->timings;
382 	struct				device *dev = emif->dev;
383 
384 	/* Start with a very high frequency - 1GHz */
385 	freq_nearest = 1000000000;
386 
387 	/*
388 	 * Find the timings table such that:
389 	 *  1. the frequency range covers the required frequency(safe) AND
390 	 *  2. the max_freq is closest to the required frequency(optimal)
391 	 */
392 	for (i = 0; i < emif->plat_data->timings_arr_size; i++) {
393 		max = timings_arr[i].max_freq;
394 		min = timings_arr[i].min_freq;
395 		if ((freq >= min) && (freq <= max) && (max < freq_nearest)) {
396 			freq_nearest = max;
397 			timings = &timings_arr[i];
398 		}
399 	}
400 
401 	if (!timings)
402 		dev_err(dev, "%s: couldn't find timings for - %dHz\n",
403 			__func__, freq);
404 
405 	dev_dbg(dev, "%s: timings table: freq %d, speed bin freq %d\n",
406 		__func__, freq, freq_nearest);
407 
408 	return timings;
409 }
410 
411 static u32 get_sdram_ref_ctrl_shdw(u32 freq,
412 		const struct lpddr2_addressing *addressing)
413 {
414 	u32 ref_ctrl_shdw = 0, val = 0, freq_khz, t_refi;
415 
416 	/* Scale down frequency and t_refi to avoid overflow */
417 	freq_khz = freq / 1000;
418 	t_refi = addressing->tREFI_ns / 100;
419 
420 	/*
421 	 * refresh rate to be set is 'tREFI(in us) * freq in MHz
422 	 * division by 10000 to account for change in units
423 	 */
424 	val = t_refi * freq_khz / 10000;
425 	ref_ctrl_shdw |= val << REFRESH_RATE_SHIFT;
426 
427 	return ref_ctrl_shdw;
428 }
429 
430 static u32 get_sdram_tim_1_shdw(const struct lpddr2_timings *timings,
431 		const struct lpddr2_min_tck *min_tck,
432 		const struct lpddr2_addressing *addressing)
433 {
434 	u32 tim1 = 0, val = 0;
435 
436 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
437 	tim1 |= val << T_WTR_SHIFT;
438 
439 	if (addressing->num_banks == B8)
440 		val = DIV_ROUND_UP(timings->tFAW, t_ck*4);
441 	else
442 		val = max(min_tck->tRRD, DIV_ROUND_UP(timings->tRRD, t_ck));
443 	tim1 |= (val - 1) << T_RRD_SHIFT;
444 
445 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab, t_ck) - 1;
446 	tim1 |= val << T_RC_SHIFT;
447 
448 	val = max(min_tck->tRASmin, DIV_ROUND_UP(timings->tRAS_min, t_ck));
449 	tim1 |= (val - 1) << T_RAS_SHIFT;
450 
451 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
452 	tim1 |= val << T_WR_SHIFT;
453 
454 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD, t_ck)) - 1;
455 	tim1 |= val << T_RCD_SHIFT;
456 
457 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab, t_ck)) - 1;
458 	tim1 |= val << T_RP_SHIFT;
459 
460 	return tim1;
461 }
462 
463 static u32 get_sdram_tim_1_shdw_derated(const struct lpddr2_timings *timings,
464 		const struct lpddr2_min_tck *min_tck,
465 		const struct lpddr2_addressing *addressing)
466 {
467 	u32 tim1 = 0, val = 0;
468 
469 	val = max(min_tck->tWTR, DIV_ROUND_UP(timings->tWTR, t_ck)) - 1;
470 	tim1 = val << T_WTR_SHIFT;
471 
472 	/*
473 	 * tFAW is approximately 4 times tRRD. So add 1875*4 = 7500ps
474 	 * to tFAW for de-rating
475 	 */
476 	if (addressing->num_banks == B8) {
477 		val = DIV_ROUND_UP(timings->tFAW + 7500, 4 * t_ck) - 1;
478 	} else {
479 		val = DIV_ROUND_UP(timings->tRRD + 1875, t_ck);
480 		val = max(min_tck->tRRD, val) - 1;
481 	}
482 	tim1 |= val << T_RRD_SHIFT;
483 
484 	val = DIV_ROUND_UP(timings->tRAS_min + timings->tRPab + 1875, t_ck);
485 	tim1 |= (val - 1) << T_RC_SHIFT;
486 
487 	val = DIV_ROUND_UP(timings->tRAS_min + 1875, t_ck);
488 	val = max(min_tck->tRASmin, val) - 1;
489 	tim1 |= val << T_RAS_SHIFT;
490 
491 	val = max(min_tck->tWR, DIV_ROUND_UP(timings->tWR, t_ck)) - 1;
492 	tim1 |= val << T_WR_SHIFT;
493 
494 	val = max(min_tck->tRCD, DIV_ROUND_UP(timings->tRCD + 1875, t_ck));
495 	tim1 |= (val - 1) << T_RCD_SHIFT;
496 
497 	val = max(min_tck->tRPab, DIV_ROUND_UP(timings->tRPab + 1875, t_ck));
498 	tim1 |= (val - 1) << T_RP_SHIFT;
499 
500 	return tim1;
501 }
502 
503 static u32 get_sdram_tim_2_shdw(const struct lpddr2_timings *timings,
504 		const struct lpddr2_min_tck *min_tck,
505 		const struct lpddr2_addressing *addressing,
506 		u32 type)
507 {
508 	u32 tim2 = 0, val = 0;
509 
510 	val = min_tck->tCKE - 1;
511 	tim2 |= val << T_CKE_SHIFT;
512 
513 	val = max(min_tck->tRTP, DIV_ROUND_UP(timings->tRTP, t_ck)) - 1;
514 	tim2 |= val << T_RTP_SHIFT;
515 
516 	/* tXSNR = tRFCab_ps + 10 ns(tRFCab_ps for LPDDR2). */
517 	val = DIV_ROUND_UP(addressing->tRFCab_ps + 10000, t_ck) - 1;
518 	tim2 |= val << T_XSNR_SHIFT;
519 
520 	/* XSRD same as XSNR for LPDDR2 */
521 	tim2 |= val << T_XSRD_SHIFT;
522 
523 	val = max(min_tck->tXP, DIV_ROUND_UP(timings->tXP, t_ck)) - 1;
524 	tim2 |= val << T_XP_SHIFT;
525 
526 	return tim2;
527 }
528 
529 static u32 get_sdram_tim_3_shdw(const struct lpddr2_timings *timings,
530 		const struct lpddr2_min_tck *min_tck,
531 		const struct lpddr2_addressing *addressing,
532 		u32 type, u32 ip_rev, u32 derated)
533 {
534 	u32 tim3 = 0, val = 0, t_dqsck;
535 
536 	val = timings->tRAS_max_ns / addressing->tREFI_ns - 1;
537 	val = val > 0xF ? 0xF : val;
538 	tim3 |= val << T_RAS_MAX_SHIFT;
539 
540 	val = DIV_ROUND_UP(addressing->tRFCab_ps, t_ck) - 1;
541 	tim3 |= val << T_RFC_SHIFT;
542 
543 	t_dqsck = (derated == EMIF_DERATED_TIMINGS) ?
544 		timings->tDQSCK_max_derated : timings->tDQSCK_max;
545 	if (ip_rev == EMIF_4D5)
546 		val = DIV_ROUND_UP(t_dqsck + 1000, t_ck) - 1;
547 	else
548 		val = DIV_ROUND_UP(t_dqsck, t_ck) - 1;
549 
550 	tim3 |= val << T_TDQSCKMAX_SHIFT;
551 
552 	val = DIV_ROUND_UP(timings->tZQCS, t_ck) - 1;
553 	tim3 |= val << ZQ_ZQCS_SHIFT;
554 
555 	val = DIV_ROUND_UP(timings->tCKESR, t_ck);
556 	val = max(min_tck->tCKESR, val) - 1;
557 	tim3 |= val << T_CKESR_SHIFT;
558 
559 	if (ip_rev == EMIF_4D5) {
560 		tim3 |= (EMIF_T_CSTA - 1) << T_CSTA_SHIFT;
561 
562 		val = DIV_ROUND_UP(EMIF_T_PDLL_UL, 128) - 1;
563 		tim3 |= val << T_PDLL_UL_SHIFT;
564 	}
565 
566 	return tim3;
567 }
568 
569 static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
570 		bool cs1_used, bool cal_resistors_per_cs)
571 {
572 	u32 zq = 0, val = 0;
573 
574 	val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
575 	zq |= val << ZQ_REFINTERVAL_SHIFT;
576 
577 	val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
578 	zq |= val << ZQ_ZQCL_MULT_SHIFT;
579 
580 	val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
581 	zq |= val << ZQ_ZQINIT_MULT_SHIFT;
582 
583 	zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
584 
585 	if (cal_resistors_per_cs)
586 		zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
587 	else
588 		zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
589 
590 	zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
591 
592 	val = cs1_used ? 1 : 0;
593 	zq |= val << ZQ_CS1EN_SHIFT;
594 
595 	return zq;
596 }
597 
598 static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
599 		const struct emif_custom_configs *custom_configs, bool cs1_used,
600 		u32 sdram_io_width, u32 emif_bus_width)
601 {
602 	u32 alert = 0, interval, devcnt;
603 
604 	if (custom_configs && (custom_configs->mask &
605 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
606 		interval = custom_configs->temp_alert_poll_interval_ms;
607 	else
608 		interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
609 
610 	interval *= 1000000;			/* Convert to ns */
611 	interval /= addressing->tREFI_ns;	/* Convert to refresh cycles */
612 	alert |= (interval << TA_REFINTERVAL_SHIFT);
613 
614 	/*
615 	 * sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
616 	 * also to this form and subtract to get TA_DEVCNT, which is
617 	 * in log2(x) form.
618 	 */
619 	emif_bus_width = __fls(emif_bus_width) - 1;
620 	devcnt = emif_bus_width - sdram_io_width;
621 	alert |= devcnt << TA_DEVCNT_SHIFT;
622 
623 	/* DEVWDT is in 'log2(x) - 3' form */
624 	alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
625 
626 	alert |= 1 << TA_SFEXITEN_SHIFT;
627 	alert |= 1 << TA_CS0EN_SHIFT;
628 	alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
629 
630 	return alert;
631 }
632 
633 static u32 get_read_idle_ctrl_shdw(u8 volt_ramp)
634 {
635 	u32 idle = 0, val = 0;
636 
637 	/*
638 	 * Maximum value in normal conditions and increased frequency
639 	 * when voltage is ramping
640 	 */
641 	if (volt_ramp)
642 		val = READ_IDLE_INTERVAL_DVFS / t_ck / 64 - 1;
643 	else
644 		val = 0x1FF;
645 
646 	/*
647 	 * READ_IDLE_CTRL register in EMIF4D has same offset and fields
648 	 * as DLL_CALIB_CTRL in EMIF4D5, so use the same shifts
649 	 */
650 	idle |= val << DLL_CALIB_INTERVAL_SHIFT;
651 	idle |= EMIF_READ_IDLE_LEN_VAL << ACK_WAIT_SHIFT;
652 
653 	return idle;
654 }
655 
656 static u32 get_dll_calib_ctrl_shdw(u8 volt_ramp)
657 {
658 	u32 calib = 0, val = 0;
659 
660 	if (volt_ramp == DDR_VOLTAGE_RAMPING)
661 		val = DLL_CALIB_INTERVAL_DVFS / t_ck / 16 - 1;
662 	else
663 		val = 0; /* Disabled when voltage is stable */
664 
665 	calib |= val << DLL_CALIB_INTERVAL_SHIFT;
666 	calib |= DLL_CALIB_ACK_WAIT_VAL << ACK_WAIT_SHIFT;
667 
668 	return calib;
669 }
670 
671 static u32 get_ddr_phy_ctrl_1_attilaphy_4d(const struct lpddr2_timings *timings,
672 	u32 freq, u8 RL)
673 {
674 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_ATTILAPHY, val = 0;
675 
676 	val = RL + DIV_ROUND_UP(timings->tDQSCK_max, t_ck) - 1;
677 	phy |= val << READ_LATENCY_SHIFT_4D;
678 
679 	if (freq <= 100000000)
680 		val = EMIF_DLL_SLAVE_DLY_CTRL_100_MHZ_AND_LESS_ATTILAPHY;
681 	else if (freq <= 200000000)
682 		val = EMIF_DLL_SLAVE_DLY_CTRL_200_MHZ_ATTILAPHY;
683 	else
684 		val = EMIF_DLL_SLAVE_DLY_CTRL_400_MHZ_ATTILAPHY;
685 
686 	phy |= val << DLL_SLAVE_DLY_CTRL_SHIFT_4D;
687 
688 	return phy;
689 }
690 
691 static u32 get_phy_ctrl_1_intelliphy_4d5(u32 freq, u8 cl)
692 {
693 	u32 phy = EMIF_DDR_PHY_CTRL_1_BASE_VAL_INTELLIPHY, half_delay;
694 
695 	/*
696 	 * DLL operates at 266 MHz. If DDR frequency is near 266 MHz,
697 	 * half-delay is not needed else set half-delay
698 	 */
699 	if (freq >= 265000000 && freq < 267000000)
700 		half_delay = 0;
701 	else
702 		half_delay = 1;
703 
704 	phy |= half_delay << DLL_HALF_DELAY_SHIFT_4D5;
705 	phy |= ((cl + DIV_ROUND_UP(EMIF_PHY_TOTAL_READ_LATENCY_INTELLIPHY_PS,
706 			t_ck) - 1) << READ_LATENCY_SHIFT_4D5);
707 
708 	return phy;
709 }
710 
711 static u32 get_ext_phy_ctrl_2_intelliphy_4d5(void)
712 {
713 	u32 fifo_we_slave_ratio;
714 
715 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
716 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
717 
718 	return fifo_we_slave_ratio | fifo_we_slave_ratio << 11 |
719 		fifo_we_slave_ratio << 22;
720 }
721 
722 static u32 get_ext_phy_ctrl_3_intelliphy_4d5(void)
723 {
724 	u32 fifo_we_slave_ratio;
725 
726 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
727 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
728 
729 	return fifo_we_slave_ratio >> 10 | fifo_we_slave_ratio << 1 |
730 		fifo_we_slave_ratio << 12 | fifo_we_slave_ratio << 23;
731 }
732 
733 static u32 get_ext_phy_ctrl_4_intelliphy_4d5(void)
734 {
735 	u32 fifo_we_slave_ratio;
736 
737 	fifo_we_slave_ratio =  DIV_ROUND_CLOSEST(
738 		EMIF_INTELLI_PHY_DQS_GATE_OPENING_DELAY_PS * 256 , t_ck);
739 
740 	return fifo_we_slave_ratio >> 9 | fifo_we_slave_ratio << 2 |
741 		fifo_we_slave_ratio << 13;
742 }
743 
744 static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
745 {
746 	u32 pwr_mgmt_ctrl	= 0, timeout;
747 	u32 lpmode		= EMIF_LP_MODE_SELF_REFRESH;
748 	u32 timeout_perf	= EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
749 	u32 timeout_pwr		= EMIF_LP_MODE_TIMEOUT_POWER;
750 	u32 freq_threshold	= EMIF_LP_MODE_FREQ_THRESHOLD;
751 	u32 mask;
752 	u8 shift;
753 
754 	struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
755 
756 	if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
757 		lpmode		= cust_cfgs->lpmode;
758 		timeout_perf	= cust_cfgs->lpmode_timeout_performance;
759 		timeout_pwr	= cust_cfgs->lpmode_timeout_power;
760 		freq_threshold  = cust_cfgs->lpmode_freq_threshold;
761 	}
762 
763 	/* Timeout based on DDR frequency */
764 	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
765 
766 	/*
767 	 * The value to be set in register is "log2(timeout) - 3"
768 	 * if timeout < 16 load 0 in register
769 	 * if timeout is not a power of 2, round to next highest power of 2
770 	 */
771 	if (timeout < 16) {
772 		timeout = 0;
773 	} else {
774 		if (timeout & (timeout - 1))
775 			timeout <<= 1;
776 		timeout = __fls(timeout) - 3;
777 	}
778 
779 	switch (lpmode) {
780 	case EMIF_LP_MODE_CLOCK_STOP:
781 		shift = CS_TIM_SHIFT;
782 		mask = CS_TIM_MASK;
783 		break;
784 	case EMIF_LP_MODE_SELF_REFRESH:
785 		/* Workaround for errata i735 */
786 		if (timeout < 6)
787 			timeout = 6;
788 
789 		shift = SR_TIM_SHIFT;
790 		mask = SR_TIM_MASK;
791 		break;
792 	case EMIF_LP_MODE_PWR_DN:
793 		shift = PD_TIM_SHIFT;
794 		mask = PD_TIM_MASK;
795 		break;
796 	case EMIF_LP_MODE_DISABLE:
797 	default:
798 		mask = 0;
799 		shift = 0;
800 		break;
801 	}
802 	/* Round to maximum in case of overflow, BUT warn! */
803 	if (lpmode != EMIF_LP_MODE_DISABLE && timeout > mask >> shift) {
804 		pr_err("TIMEOUT Overflow - lpmode=%d perf=%d pwr=%d freq=%d\n",
805 		       lpmode,
806 		       timeout_perf,
807 		       timeout_pwr,
808 		       freq_threshold);
809 		WARN(1, "timeout=0x%02x greater than 0x%02x. Using max\n",
810 		     timeout, mask >> shift);
811 		timeout = mask >> shift;
812 	}
813 
814 	/* Setup required timing */
815 	pwr_mgmt_ctrl = (timeout << shift) & mask;
816 	/* setup a default mask for rest of the modes */
817 	pwr_mgmt_ctrl |= (SR_TIM_MASK | CS_TIM_MASK | PD_TIM_MASK) &
818 			  ~mask;
819 
820 	/* No CS_TIM in EMIF_4D5 */
821 	if (ip_rev == EMIF_4D5)
822 		pwr_mgmt_ctrl &= ~CS_TIM_MASK;
823 
824 	pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
825 
826 	return pwr_mgmt_ctrl;
827 }
828 
829 /*
830  * Get the temperature level of the EMIF instance:
831  * Reads the MR4 register of attached SDRAM parts to find out the temperature
832  * level. If there are two parts attached(one on each CS), then the temperature
833  * level for the EMIF instance is the higher of the two temperatures.
834  */
835 static void get_temperature_level(struct emif_data *emif)
836 {
837 	u32		temp, temperature_level;
838 	void __iomem	*base;
839 
840 	base = emif->base;
841 
842 	/* Read mode register 4 */
843 	writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
844 	temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
845 	temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
846 				MR4_SDRAM_REF_RATE_SHIFT;
847 
848 	if (emif->plat_data->device_info->cs1_used) {
849 		writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
850 		temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
851 		temp = (temp & MR4_SDRAM_REF_RATE_MASK)
852 				>> MR4_SDRAM_REF_RATE_SHIFT;
853 		temperature_level = max(temp, temperature_level);
854 	}
855 
856 	/* treat everything less than nominal(3) in MR4 as nominal */
857 	if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
858 		temperature_level = SDRAM_TEMP_NOMINAL;
859 
860 	/* if we get reserved value in MR4 persist with the existing value */
861 	if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
862 		emif->temperature_level = temperature_level;
863 }
864 
865 /*
866  * Program EMIF shadow registers that are not dependent on temperature
867  * or voltage
868  */
869 static void setup_registers(struct emif_data *emif, struct emif_regs *regs)
870 {
871 	void __iomem	*base = emif->base;
872 
873 	writel(regs->sdram_tim2_shdw, base + EMIF_SDRAM_TIMING_2_SHDW);
874 	writel(regs->phy_ctrl_1_shdw, base + EMIF_DDR_PHY_CTRL_1_SHDW);
875 	writel(regs->pwr_mgmt_ctrl_shdw,
876 	       base + EMIF_POWER_MANAGEMENT_CTRL_SHDW);
877 
878 	/* Settings specific for EMIF4D5 */
879 	if (emif->plat_data->ip_rev != EMIF_4D5)
880 		return;
881 	writel(regs->ext_phy_ctrl_2_shdw, base + EMIF_EXT_PHY_CTRL_2_SHDW);
882 	writel(regs->ext_phy_ctrl_3_shdw, base + EMIF_EXT_PHY_CTRL_3_SHDW);
883 	writel(regs->ext_phy_ctrl_4_shdw, base + EMIF_EXT_PHY_CTRL_4_SHDW);
884 }
885 
886 /*
887  * When voltage ramps dll calibration and forced read idle should
888  * happen more often
889  */
890 static void setup_volt_sensitive_regs(struct emif_data *emif,
891 		struct emif_regs *regs, u32 volt_state)
892 {
893 	u32		calib_ctrl;
894 	void __iomem	*base = emif->base;
895 
896 	/*
897 	 * EMIF_READ_IDLE_CTRL in EMIF4D refers to the same register as
898 	 * EMIF_DLL_CALIB_CTRL in EMIF4D5 and dll_calib_ctrl_shadow_*
899 	 * is an alias of the respective read_idle_ctrl_shdw_* (members of
900 	 * a union). So, the below code takes care of both cases
901 	 */
902 	if (volt_state == DDR_VOLTAGE_RAMPING)
903 		calib_ctrl = regs->dll_calib_ctrl_shdw_volt_ramp;
904 	else
905 		calib_ctrl = regs->dll_calib_ctrl_shdw_normal;
906 
907 	writel(calib_ctrl, base + EMIF_DLL_CALIB_CTRL_SHDW);
908 }
909 
910 /*
911  * setup_temperature_sensitive_regs() - set the timings for temperature
912  * sensitive registers. This happens once at initialisation time based
913  * on the temperature at boot time and subsequently based on the temperature
914  * alert interrupt. Temperature alert can happen when the temperature
915  * increases or drops. So this function can have the effect of either
916  * derating the timings or going back to nominal values.
917  */
918 static void setup_temperature_sensitive_regs(struct emif_data *emif,
919 		struct emif_regs *regs)
920 {
921 	u32		tim1, tim3, ref_ctrl, type;
922 	void __iomem	*base = emif->base;
923 	u32		temperature;
924 
925 	type = emif->plat_data->device_info->type;
926 
927 	tim1 = regs->sdram_tim1_shdw;
928 	tim3 = regs->sdram_tim3_shdw;
929 	ref_ctrl = regs->ref_ctrl_shdw;
930 
931 	/* No de-rating for non-lpddr2 devices */
932 	if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
933 		goto out;
934 
935 	temperature = emif->temperature_level;
936 	if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
937 		ref_ctrl = regs->ref_ctrl_shdw_derated;
938 	} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
939 		tim1 = regs->sdram_tim1_shdw_derated;
940 		tim3 = regs->sdram_tim3_shdw_derated;
941 		ref_ctrl = regs->ref_ctrl_shdw_derated;
942 	}
943 
944 out:
945 	writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
946 	writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
947 	writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
948 }
949 
950 static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
951 {
952 	u32		old_temp_level;
953 	irqreturn_t	ret = IRQ_HANDLED;
954 	struct emif_custom_configs *custom_configs;
955 
956 	spin_lock_irqsave(&emif_lock, irq_state);
957 	old_temp_level = emif->temperature_level;
958 	get_temperature_level(emif);
959 
960 	if (unlikely(emif->temperature_level == old_temp_level)) {
961 		goto out;
962 	} else if (!emif->curr_regs) {
963 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
964 		goto out;
965 	}
966 
967 	custom_configs = emif->plat_data->custom_configs;
968 
969 	/*
970 	 * IF we detect higher than "nominal rating" from DDR sensor
971 	 * on an unsupported DDR part, shutdown system
972 	 */
973 	if (custom_configs && !(custom_configs->mask &
974 				EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART)) {
975 		if (emif->temperature_level >= SDRAM_TEMP_HIGH_DERATE_REFRESH) {
976 			dev_err(emif->dev,
977 				"%s:NOT Extended temperature capable memory."
978 				"Converting MR4=0x%02x as shutdown event\n",
979 				__func__, emif->temperature_level);
980 			/*
981 			 * Temperature far too high - do kernel_power_off()
982 			 * from thread context
983 			 */
984 			emif->temperature_level = SDRAM_TEMP_VERY_HIGH_SHUTDOWN;
985 			ret = IRQ_WAKE_THREAD;
986 			goto out;
987 		}
988 	}
989 
990 	if (emif->temperature_level < old_temp_level ||
991 		emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
992 		/*
993 		 * Temperature coming down - defer handling to thread OR
994 		 * Temperature far too high - do kernel_power_off() from
995 		 * thread context
996 		 */
997 		ret = IRQ_WAKE_THREAD;
998 	} else {
999 		/* Temperature is going up - handle immediately */
1000 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
1001 		do_freq_update();
1002 	}
1003 
1004 out:
1005 	spin_unlock_irqrestore(&emif_lock, irq_state);
1006 	return ret;
1007 }
1008 
1009 static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
1010 {
1011 	u32			interrupts;
1012 	struct emif_data	*emif = dev_id;
1013 	void __iomem		*base = emif->base;
1014 	struct device		*dev = emif->dev;
1015 	irqreturn_t		ret = IRQ_HANDLED;
1016 
1017 	/* Save the status and clear it */
1018 	interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1019 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1020 
1021 	/*
1022 	 * Handle temperature alert
1023 	 * Temperature alert should be same for all ports
1024 	 * So, it's enough to process it only for one of the ports
1025 	 */
1026 	if (interrupts & TA_SYS_MASK)
1027 		ret = handle_temp_alert(base, emif);
1028 
1029 	if (interrupts & ERR_SYS_MASK)
1030 		dev_err(dev, "Access error from SYS port - %x\n", interrupts);
1031 
1032 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1033 		/* Save the status and clear it */
1034 		interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
1035 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
1036 
1037 		if (interrupts & ERR_LL_MASK)
1038 			dev_err(dev, "Access error from LL port - %x\n",
1039 				interrupts);
1040 	}
1041 
1042 	return ret;
1043 }
1044 
1045 static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
1046 {
1047 	struct emif_data	*emif = dev_id;
1048 
1049 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
1050 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1051 
1052 		/* If we have Power OFF ability, use it, else try restarting */
1053 		if (pm_power_off) {
1054 			kernel_power_off();
1055 		} else {
1056 			WARN(1, "FIXME: NO pm_power_off!!! trying restart\n");
1057 			kernel_restart("SDRAM Over-temp Emergency restart");
1058 		}
1059 		return IRQ_HANDLED;
1060 	}
1061 
1062 	spin_lock_irqsave(&emif_lock, irq_state);
1063 
1064 	if (emif->curr_regs) {
1065 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
1066 		do_freq_update();
1067 	} else {
1068 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
1069 	}
1070 
1071 	spin_unlock_irqrestore(&emif_lock, irq_state);
1072 
1073 	return IRQ_HANDLED;
1074 }
1075 
1076 static void clear_all_interrupts(struct emif_data *emif)
1077 {
1078 	void __iomem	*base = emif->base;
1079 
1080 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
1081 		base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
1082 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1083 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
1084 			base + EMIF_LL_OCP_INTERRUPT_STATUS);
1085 }
1086 
1087 static void disable_and_clear_all_interrupts(struct emif_data *emif)
1088 {
1089 	void __iomem		*base = emif->base;
1090 
1091 	/* Disable all interrupts */
1092 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
1093 		base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
1094 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
1095 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
1096 			base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
1097 
1098 	/* Clear all interrupts */
1099 	clear_all_interrupts(emif);
1100 }
1101 
1102 static int __init_or_module setup_interrupts(struct emif_data *emif, u32 irq)
1103 {
1104 	u32		interrupts, type;
1105 	void __iomem	*base = emif->base;
1106 
1107 	type = emif->plat_data->device_info->type;
1108 
1109 	clear_all_interrupts(emif);
1110 
1111 	/* Enable interrupts for SYS interface */
1112 	interrupts = EN_ERR_SYS_MASK;
1113 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
1114 		interrupts |= EN_TA_SYS_MASK;
1115 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
1116 
1117 	/* Enable interrupts for LL interface */
1118 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
1119 		/* TA need not be enabled for LL */
1120 		interrupts = EN_ERR_LL_MASK;
1121 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
1122 	}
1123 
1124 	/* setup IRQ handlers */
1125 	return devm_request_threaded_irq(emif->dev, irq,
1126 				    emif_interrupt_handler,
1127 				    emif_threaded_isr,
1128 				    0, dev_name(emif->dev),
1129 				    emif);
1130 
1131 }
1132 
1133 static void __init_or_module emif_onetime_settings(struct emif_data *emif)
1134 {
1135 	u32				pwr_mgmt_ctrl, zq, temp_alert_cfg;
1136 	void __iomem			*base = emif->base;
1137 	const struct lpddr2_addressing	*addressing;
1138 	const struct ddr_device_info	*device_info;
1139 
1140 	device_info = emif->plat_data->device_info;
1141 	addressing = get_addressing_table(device_info);
1142 
1143 	/*
1144 	 * Init power management settings
1145 	 * We don't know the frequency yet. Use a high frequency
1146 	 * value for a conservative timeout setting
1147 	 */
1148 	pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
1149 			emif->plat_data->ip_rev);
1150 	emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
1151 	writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
1152 
1153 	/* Init ZQ calibration settings */
1154 	zq = get_zq_config_reg(addressing, device_info->cs1_used,
1155 		device_info->cal_resistors_per_cs);
1156 	writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
1157 
1158 	/* Check temperature level temperature level*/
1159 	get_temperature_level(emif);
1160 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
1161 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
1162 
1163 	/* Init temperature polling */
1164 	temp_alert_cfg = get_temp_alert_config(addressing,
1165 		emif->plat_data->custom_configs, device_info->cs1_used,
1166 		device_info->io_width, get_emif_bus_width(emif));
1167 	writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
1168 
1169 	/*
1170 	 * Program external PHY control registers that are not frequency
1171 	 * dependent
1172 	 */
1173 	if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
1174 		return;
1175 	writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
1176 	writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
1177 	writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
1178 	writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
1179 	writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
1180 	writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
1181 	writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
1182 	writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
1183 	writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
1184 	writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
1185 	writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
1186 	writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
1187 	writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
1188 	writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
1189 	writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
1190 	writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
1191 	writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
1192 	writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
1193 	writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
1194 	writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
1195 	writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
1196 }
1197 
1198 static void get_default_timings(struct emif_data *emif)
1199 {
1200 	struct emif_platform_data *pd = emif->plat_data;
1201 
1202 	pd->timings		= lpddr2_jedec_timings;
1203 	pd->timings_arr_size	= ARRAY_SIZE(lpddr2_jedec_timings);
1204 
1205 	dev_warn(emif->dev, "%s: using default timings\n", __func__);
1206 }
1207 
1208 static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
1209 		u32 ip_rev, struct device *dev)
1210 {
1211 	int valid;
1212 
1213 	valid = (type == DDR_TYPE_LPDDR2_S4 ||
1214 			type == DDR_TYPE_LPDDR2_S2)
1215 		&& (density >= DDR_DENSITY_64Mb
1216 			&& density <= DDR_DENSITY_8Gb)
1217 		&& (io_width >= DDR_IO_WIDTH_8
1218 			&& io_width <= DDR_IO_WIDTH_32);
1219 
1220 	/* Combinations of EMIF and PHY revisions that we support today */
1221 	switch (ip_rev) {
1222 	case EMIF_4D:
1223 		valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
1224 		break;
1225 	case EMIF_4D5:
1226 		valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
1227 		break;
1228 	default:
1229 		valid = 0;
1230 	}
1231 
1232 	if (!valid)
1233 		dev_err(dev, "%s: invalid DDR details\n", __func__);
1234 	return valid;
1235 }
1236 
1237 static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
1238 		struct device *dev)
1239 {
1240 	int valid = 1;
1241 
1242 	if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
1243 		(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
1244 		valid = cust_cfgs->lpmode_freq_threshold &&
1245 			cust_cfgs->lpmode_timeout_performance &&
1246 			cust_cfgs->lpmode_timeout_power;
1247 
1248 	if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
1249 		valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
1250 
1251 	if (!valid)
1252 		dev_warn(dev, "%s: invalid custom configs\n", __func__);
1253 
1254 	return valid;
1255 }
1256 
1257 #if defined(CONFIG_OF)
1258 static void __init_or_module of_get_custom_configs(struct device_node *np_emif,
1259 		struct emif_data *emif)
1260 {
1261 	struct emif_custom_configs	*cust_cfgs = NULL;
1262 	int				len;
1263 	const __be32			*lpmode, *poll_intvl;
1264 
1265 	lpmode = of_get_property(np_emif, "low-power-mode", &len);
1266 	poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
1267 
1268 	if (lpmode || poll_intvl)
1269 		cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
1270 			GFP_KERNEL);
1271 
1272 	if (!cust_cfgs)
1273 		return;
1274 
1275 	if (lpmode) {
1276 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
1277 		cust_cfgs->lpmode = be32_to_cpup(lpmode);
1278 		of_property_read_u32(np_emif,
1279 				"low-power-mode-timeout-performance",
1280 				&cust_cfgs->lpmode_timeout_performance);
1281 		of_property_read_u32(np_emif,
1282 				"low-power-mode-timeout-power",
1283 				&cust_cfgs->lpmode_timeout_power);
1284 		of_property_read_u32(np_emif,
1285 				"low-power-mode-freq-threshold",
1286 				&cust_cfgs->lpmode_freq_threshold);
1287 	}
1288 
1289 	if (poll_intvl) {
1290 		cust_cfgs->mask |=
1291 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
1292 		cust_cfgs->temp_alert_poll_interval_ms =
1293 						be32_to_cpup(poll_intvl);
1294 	}
1295 
1296 	if (of_find_property(np_emif, "extended-temp-part", &len))
1297 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART;
1298 
1299 	if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
1300 		devm_kfree(emif->dev, cust_cfgs);
1301 		return;
1302 	}
1303 
1304 	emif->plat_data->custom_configs = cust_cfgs;
1305 }
1306 
1307 static void __init_or_module of_get_ddr_info(struct device_node *np_emif,
1308 		struct device_node *np_ddr,
1309 		struct ddr_device_info *dev_info)
1310 {
1311 	u32 density = 0, io_width = 0;
1312 	int len;
1313 
1314 	if (of_find_property(np_emif, "cs1-used", &len))
1315 		dev_info->cs1_used = true;
1316 
1317 	if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
1318 		dev_info->cal_resistors_per_cs = true;
1319 
1320 	if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s4"))
1321 		dev_info->type = DDR_TYPE_LPDDR2_S4;
1322 	else if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s2"))
1323 		dev_info->type = DDR_TYPE_LPDDR2_S2;
1324 
1325 	of_property_read_u32(np_ddr, "density", &density);
1326 	of_property_read_u32(np_ddr, "io-width", &io_width);
1327 
1328 	/* Convert from density in Mb to the density encoding in jedc_ddr.h */
1329 	if (density & (density - 1))
1330 		dev_info->density = 0;
1331 	else
1332 		dev_info->density = __fls(density) - 5;
1333 
1334 	/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
1335 	if (io_width & (io_width - 1))
1336 		dev_info->io_width = 0;
1337 	else
1338 		dev_info->io_width = __fls(io_width) - 1;
1339 }
1340 
1341 static struct emif_data * __init_or_module of_get_memory_device_details(
1342 		struct device_node *np_emif, struct device *dev)
1343 {
1344 	struct emif_data		*emif = NULL;
1345 	struct ddr_device_info		*dev_info = NULL;
1346 	struct emif_platform_data	*pd = NULL;
1347 	struct device_node		*np_ddr;
1348 	int				len;
1349 
1350 	np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
1351 	if (!np_ddr)
1352 		goto error;
1353 	emif	= devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
1354 	pd	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1355 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1356 
1357 	if (!emif || !pd || !dev_info) {
1358 		dev_err(dev, "%s: Out of memory!!\n",
1359 			__func__);
1360 		goto error;
1361 	}
1362 
1363 	emif->plat_data		= pd;
1364 	pd->device_info		= dev_info;
1365 	emif->dev		= dev;
1366 	emif->np_ddr		= np_ddr;
1367 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1368 
1369 	if (of_device_is_compatible(np_emif, "ti,emif-4d"))
1370 		emif->plat_data->ip_rev = EMIF_4D;
1371 	else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
1372 		emif->plat_data->ip_rev = EMIF_4D5;
1373 
1374 	of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
1375 
1376 	if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
1377 		pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
1378 
1379 	of_get_ddr_info(np_emif, np_ddr, dev_info);
1380 	if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
1381 			pd->device_info->io_width, pd->phy_type, pd->ip_rev,
1382 			emif->dev)) {
1383 		dev_err(dev, "%s: invalid device data!!\n", __func__);
1384 		goto error;
1385 	}
1386 	/*
1387 	 * For EMIF instances other than EMIF1 see if the devices connected
1388 	 * are exactly same as on EMIF1(which is typically the case). If so,
1389 	 * mark it as a duplicate of EMIF1. This will save some memory and
1390 	 * computation.
1391 	 */
1392 	if (emif1 && emif1->np_ddr == np_ddr) {
1393 		emif->duplicate = true;
1394 		goto out;
1395 	} else if (emif1) {
1396 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1397 			__func__);
1398 	}
1399 
1400 	of_get_custom_configs(np_emif, emif);
1401 	emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
1402 					emif->plat_data->device_info->type,
1403 					&emif->plat_data->timings_arr_size);
1404 
1405 	emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
1406 	goto out;
1407 
1408 error:
1409 	return NULL;
1410 out:
1411 	return emif;
1412 }
1413 
1414 #else
1415 
1416 static struct emif_data * __init_or_module of_get_memory_device_details(
1417 		struct device_node *np_emif, struct device *dev)
1418 {
1419 	return NULL;
1420 }
1421 #endif
1422 
1423 static struct emif_data *__init_or_module get_device_details(
1424 		struct platform_device *pdev)
1425 {
1426 	u32				size;
1427 	struct emif_data		*emif = NULL;
1428 	struct ddr_device_info		*dev_info;
1429 	struct emif_custom_configs	*cust_cfgs;
1430 	struct emif_platform_data	*pd;
1431 	struct device			*dev;
1432 	void				*temp;
1433 
1434 	pd = pdev->dev.platform_data;
1435 	dev = &pdev->dev;
1436 
1437 	if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
1438 			pd->device_info->density, pd->device_info->io_width,
1439 			pd->phy_type, pd->ip_rev, dev))) {
1440 		dev_err(dev, "%s: invalid device data\n", __func__);
1441 		goto error;
1442 	}
1443 
1444 	emif	= devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
1445 	temp	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1446 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1447 
1448 	if (!emif || !pd || !dev_info) {
1449 		dev_err(dev, "%s:%d: allocation error\n", __func__, __LINE__);
1450 		goto error;
1451 	}
1452 
1453 	memcpy(temp, pd, sizeof(*pd));
1454 	pd = temp;
1455 	memcpy(dev_info, pd->device_info, sizeof(*dev_info));
1456 
1457 	pd->device_info		= dev_info;
1458 	emif->plat_data		= pd;
1459 	emif->dev		= dev;
1460 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1461 
1462 	/*
1463 	 * For EMIF instances other than EMIF1 see if the devices connected
1464 	 * are exactly same as on EMIF1(which is typically the case). If so,
1465 	 * mark it as a duplicate of EMIF1 and skip copying timings data.
1466 	 * This will save some memory and some computation later.
1467 	 */
1468 	emif->duplicate = emif1 && (memcmp(dev_info,
1469 		emif1->plat_data->device_info,
1470 		sizeof(struct ddr_device_info)) == 0);
1471 
1472 	if (emif->duplicate) {
1473 		pd->timings = NULL;
1474 		pd->min_tck = NULL;
1475 		goto out;
1476 	} else if (emif1) {
1477 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1478 			__func__);
1479 	}
1480 
1481 	/*
1482 	 * Copy custom configs - ignore allocation error, if any, as
1483 	 * custom_configs is not very critical
1484 	 */
1485 	cust_cfgs = pd->custom_configs;
1486 	if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
1487 		temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
1488 		if (temp)
1489 			memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
1490 		else
1491 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1492 				__LINE__);
1493 		pd->custom_configs = temp;
1494 	}
1495 
1496 	/*
1497 	 * Copy timings and min-tck values from platform data. If it is not
1498 	 * available or if memory allocation fails, use JEDEC defaults
1499 	 */
1500 	size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
1501 	if (pd->timings) {
1502 		temp = devm_kzalloc(dev, size, GFP_KERNEL);
1503 		if (temp) {
1504 			memcpy(temp, pd->timings, size);
1505 			pd->timings = temp;
1506 		} else {
1507 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1508 				__LINE__);
1509 			get_default_timings(emif);
1510 		}
1511 	} else {
1512 		get_default_timings(emif);
1513 	}
1514 
1515 	if (pd->min_tck) {
1516 		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
1517 		if (temp) {
1518 			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
1519 			pd->min_tck = temp;
1520 		} else {
1521 			dev_warn(dev, "%s:%d: allocation error\n", __func__,
1522 				__LINE__);
1523 			pd->min_tck = &lpddr2_jedec_min_tck;
1524 		}
1525 	} else {
1526 		pd->min_tck = &lpddr2_jedec_min_tck;
1527 	}
1528 
1529 out:
1530 	return emif;
1531 
1532 error:
1533 	return NULL;
1534 }
1535 
1536 static int __init_or_module emif_probe(struct platform_device *pdev)
1537 {
1538 	struct emif_data	*emif;
1539 	struct resource		*res;
1540 	int			irq;
1541 
1542 	if (pdev->dev.of_node)
1543 		emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
1544 	else
1545 		emif = get_device_details(pdev);
1546 
1547 	if (!emif) {
1548 		pr_err("%s: error getting device data\n", __func__);
1549 		goto error;
1550 	}
1551 
1552 	list_add(&emif->node, &device_list);
1553 	emif->addressing = get_addressing_table(emif->plat_data->device_info);
1554 
1555 	/* Save pointers to each other in emif and device structures */
1556 	emif->dev = &pdev->dev;
1557 	platform_set_drvdata(pdev, emif);
1558 
1559 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1560 	emif->base = devm_ioremap_resource(emif->dev, res);
1561 	if (IS_ERR(emif->base))
1562 		goto error;
1563 
1564 	irq = platform_get_irq(pdev, 0);
1565 	if (irq < 0) {
1566 		dev_err(emif->dev, "%s: error getting IRQ resource - %d\n",
1567 			__func__, irq);
1568 		goto error;
1569 	}
1570 
1571 	emif_onetime_settings(emif);
1572 	emif_debugfs_init(emif);
1573 	disable_and_clear_all_interrupts(emif);
1574 	setup_interrupts(emif, irq);
1575 
1576 	/* One-time actions taken on probing the first device */
1577 	if (!emif1) {
1578 		emif1 = emif;
1579 		spin_lock_init(&emif_lock);
1580 
1581 		/*
1582 		 * TODO: register notifiers for frequency and voltage
1583 		 * change here once the respective frameworks are
1584 		 * available
1585 		 */
1586 	}
1587 
1588 	dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
1589 		__func__, emif->base, irq);
1590 
1591 	return 0;
1592 error:
1593 	return -ENODEV;
1594 }
1595 
1596 static int __exit emif_remove(struct platform_device *pdev)
1597 {
1598 	struct emif_data *emif = platform_get_drvdata(pdev);
1599 
1600 	emif_debugfs_exit(emif);
1601 
1602 	return 0;
1603 }
1604 
1605 static void emif_shutdown(struct platform_device *pdev)
1606 {
1607 	struct emif_data	*emif = platform_get_drvdata(pdev);
1608 
1609 	disable_and_clear_all_interrupts(emif);
1610 }
1611 
1612 static int get_emif_reg_values(struct emif_data *emif, u32 freq,
1613 		struct emif_regs *regs)
1614 {
1615 	u32				cs1_used, ip_rev, phy_type;
1616 	u32				cl, type;
1617 	const struct lpddr2_timings	*timings;
1618 	const struct lpddr2_min_tck	*min_tck;
1619 	const struct ddr_device_info	*device_info;
1620 	const struct lpddr2_addressing	*addressing;
1621 	struct emif_data		*emif_for_calc;
1622 	struct device			*dev;
1623 	const struct emif_custom_configs *custom_configs;
1624 
1625 	dev = emif->dev;
1626 	/*
1627 	 * If the devices on this EMIF instance is duplicate of EMIF1,
1628 	 * use EMIF1 details for the calculation
1629 	 */
1630 	emif_for_calc	= emif->duplicate ? emif1 : emif;
1631 	timings		= get_timings_table(emif_for_calc, freq);
1632 	addressing	= emif_for_calc->addressing;
1633 	if (!timings || !addressing) {
1634 		dev_err(dev, "%s: not enough data available for %dHz",
1635 			__func__, freq);
1636 		return -1;
1637 	}
1638 
1639 	device_info	= emif_for_calc->plat_data->device_info;
1640 	type		= device_info->type;
1641 	cs1_used	= device_info->cs1_used;
1642 	ip_rev		= emif_for_calc->plat_data->ip_rev;
1643 	phy_type	= emif_for_calc->plat_data->phy_type;
1644 
1645 	min_tck		= emif_for_calc->plat_data->min_tck;
1646 	custom_configs	= emif_for_calc->plat_data->custom_configs;
1647 
1648 	set_ddr_clk_period(freq);
1649 
1650 	regs->ref_ctrl_shdw = get_sdram_ref_ctrl_shdw(freq, addressing);
1651 	regs->sdram_tim1_shdw = get_sdram_tim_1_shdw(timings, min_tck,
1652 			addressing);
1653 	regs->sdram_tim2_shdw = get_sdram_tim_2_shdw(timings, min_tck,
1654 			addressing, type);
1655 	regs->sdram_tim3_shdw = get_sdram_tim_3_shdw(timings, min_tck,
1656 		addressing, type, ip_rev, EMIF_NORMAL_TIMINGS);
1657 
1658 	cl = get_cl(emif);
1659 
1660 	if (phy_type == EMIF_PHY_TYPE_ATTILAPHY && ip_rev == EMIF_4D) {
1661 		regs->phy_ctrl_1_shdw = get_ddr_phy_ctrl_1_attilaphy_4d(
1662 			timings, freq, cl);
1663 	} else if (phy_type == EMIF_PHY_TYPE_INTELLIPHY && ip_rev == EMIF_4D5) {
1664 		regs->phy_ctrl_1_shdw = get_phy_ctrl_1_intelliphy_4d5(freq, cl);
1665 		regs->ext_phy_ctrl_2_shdw = get_ext_phy_ctrl_2_intelliphy_4d5();
1666 		regs->ext_phy_ctrl_3_shdw = get_ext_phy_ctrl_3_intelliphy_4d5();
1667 		regs->ext_phy_ctrl_4_shdw = get_ext_phy_ctrl_4_intelliphy_4d5();
1668 	} else {
1669 		return -1;
1670 	}
1671 
1672 	/* Only timeout values in pwr_mgmt_ctrl_shdw register */
1673 	regs->pwr_mgmt_ctrl_shdw =
1674 		get_pwr_mgmt_ctrl(freq, emif_for_calc, ip_rev) &
1675 		(CS_TIM_MASK | SR_TIM_MASK | PD_TIM_MASK);
1676 
1677 	if (ip_rev & EMIF_4D) {
1678 		regs->read_idle_ctrl_shdw_normal =
1679 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_STABLE);
1680 
1681 		regs->read_idle_ctrl_shdw_volt_ramp =
1682 			get_read_idle_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1683 	} else if (ip_rev & EMIF_4D5) {
1684 		regs->dll_calib_ctrl_shdw_normal =
1685 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_STABLE);
1686 
1687 		regs->dll_calib_ctrl_shdw_volt_ramp =
1688 			get_dll_calib_ctrl_shdw(DDR_VOLTAGE_RAMPING);
1689 	}
1690 
1691 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
1692 		regs->ref_ctrl_shdw_derated = get_sdram_ref_ctrl_shdw(freq / 4,
1693 			addressing);
1694 
1695 		regs->sdram_tim1_shdw_derated =
1696 			get_sdram_tim_1_shdw_derated(timings, min_tck,
1697 				addressing);
1698 
1699 		regs->sdram_tim3_shdw_derated = get_sdram_tim_3_shdw(timings,
1700 			min_tck, addressing, type, ip_rev,
1701 			EMIF_DERATED_TIMINGS);
1702 	}
1703 
1704 	regs->freq = freq;
1705 
1706 	return 0;
1707 }
1708 
1709 /*
1710  * get_regs() - gets the cached emif_regs structure for a given EMIF instance
1711  * given frequency(freq):
1712  *
1713  * As an optimisation, every EMIF instance other than EMIF1 shares the
1714  * register cache with EMIF1 if the devices connected on this instance
1715  * are same as that on EMIF1(indicated by the duplicate flag)
1716  *
1717  * If we do not have an entry corresponding to the frequency given, we
1718  * allocate a new entry and calculate the values
1719  *
1720  * Upon finding the right reg dump, save it in curr_regs. It can be
1721  * directly used for thermal de-rating and voltage ramping changes.
1722  */
1723 static struct emif_regs *get_regs(struct emif_data *emif, u32 freq)
1724 {
1725 	int			i;
1726 	struct emif_regs	**regs_cache;
1727 	struct emif_regs	*regs = NULL;
1728 	struct device		*dev;
1729 
1730 	dev = emif->dev;
1731 	if (emif->curr_regs && emif->curr_regs->freq == freq) {
1732 		dev_dbg(dev, "%s: using curr_regs - %u Hz", __func__, freq);
1733 		return emif->curr_regs;
1734 	}
1735 
1736 	if (emif->duplicate)
1737 		regs_cache = emif1->regs_cache;
1738 	else
1739 		regs_cache = emif->regs_cache;
1740 
1741 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
1742 		if (regs_cache[i]->freq == freq) {
1743 			regs = regs_cache[i];
1744 			dev_dbg(dev,
1745 				"%s: reg dump found in reg cache for %u Hz\n",
1746 				__func__, freq);
1747 			break;
1748 		}
1749 	}
1750 
1751 	/*
1752 	 * If we don't have an entry for this frequency in the cache create one
1753 	 * and calculate the values
1754 	 */
1755 	if (!regs) {
1756 		regs = devm_kzalloc(emif->dev, sizeof(*regs), GFP_ATOMIC);
1757 		if (!regs)
1758 			return NULL;
1759 
1760 		if (get_emif_reg_values(emif, freq, regs)) {
1761 			devm_kfree(emif->dev, regs);
1762 			return NULL;
1763 		}
1764 
1765 		/*
1766 		 * Now look for an un-used entry in the cache and save the
1767 		 * newly created struct. If there are no free entries
1768 		 * over-write the last entry
1769 		 */
1770 		for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++)
1771 			;
1772 
1773 		if (i >= EMIF_MAX_NUM_FREQUENCIES) {
1774 			dev_warn(dev, "%s: regs_cache full - reusing a slot!!\n",
1775 				__func__);
1776 			i = EMIF_MAX_NUM_FREQUENCIES - 1;
1777 			devm_kfree(emif->dev, regs_cache[i]);
1778 		}
1779 		regs_cache[i] = regs;
1780 	}
1781 
1782 	return regs;
1783 }
1784 
1785 static void do_volt_notify_handling(struct emif_data *emif, u32 volt_state)
1786 {
1787 	dev_dbg(emif->dev, "%s: voltage notification : %d", __func__,
1788 		volt_state);
1789 
1790 	if (!emif->curr_regs) {
1791 		dev_err(emif->dev,
1792 			"%s: volt-notify before registers are ready: %d\n",
1793 			__func__, volt_state);
1794 		return;
1795 	}
1796 
1797 	setup_volt_sensitive_regs(emif, emif->curr_regs, volt_state);
1798 }
1799 
1800 /*
1801  * TODO: voltage notify handling should be hooked up to
1802  * regulator framework as soon as the necessary support
1803  * is available in mainline kernel. This function is un-used
1804  * right now.
1805  */
1806 static void __attribute__((unused)) volt_notify_handling(u32 volt_state)
1807 {
1808 	struct emif_data *emif;
1809 
1810 	spin_lock_irqsave(&emif_lock, irq_state);
1811 
1812 	list_for_each_entry(emif, &device_list, node)
1813 		do_volt_notify_handling(emif, volt_state);
1814 	do_freq_update();
1815 
1816 	spin_unlock_irqrestore(&emif_lock, irq_state);
1817 }
1818 
1819 static void do_freq_pre_notify_handling(struct emif_data *emif, u32 new_freq)
1820 {
1821 	struct emif_regs *regs;
1822 
1823 	regs = get_regs(emif, new_freq);
1824 	if (!regs)
1825 		return;
1826 
1827 	emif->curr_regs = regs;
1828 
1829 	/*
1830 	 * Update the shadow registers:
1831 	 * Temperature and voltage-ramp sensitive settings are also configured
1832 	 * in terms of DDR cycles. So, we need to update them too when there
1833 	 * is a freq change
1834 	 */
1835 	dev_dbg(emif->dev, "%s: setting up shadow registers for %uHz",
1836 		__func__, new_freq);
1837 	setup_registers(emif, regs);
1838 	setup_temperature_sensitive_regs(emif, regs);
1839 	setup_volt_sensitive_regs(emif, regs, DDR_VOLTAGE_STABLE);
1840 
1841 	/*
1842 	 * Part of workaround for errata i728. See do_freq_update()
1843 	 * for more details
1844 	 */
1845 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1846 		set_lpmode(emif, EMIF_LP_MODE_DISABLE);
1847 }
1848 
1849 /*
1850  * TODO: frequency notify handling should be hooked up to
1851  * clock framework as soon as the necessary support is
1852  * available in mainline kernel. This function is un-used
1853  * right now.
1854  */
1855 static void __attribute__((unused)) freq_pre_notify_handling(u32 new_freq)
1856 {
1857 	struct emif_data *emif;
1858 
1859 	/*
1860 	 * NOTE: we are taking the spin-lock here and releases it
1861 	 * only in post-notifier. This doesn't look good and
1862 	 * Sparse complains about it, but this seems to be
1863 	 * un-avoidable. We need to lock a sequence of events
1864 	 * that is split between EMIF and clock framework.
1865 	 *
1866 	 * 1. EMIF driver updates EMIF timings in shadow registers in the
1867 	 *    frequency pre-notify callback from clock framework
1868 	 * 2. clock framework sets up the registers for the new frequency
1869 	 * 3. clock framework initiates a hw-sequence that updates
1870 	 *    the frequency EMIF timings synchronously.
1871 	 *
1872 	 * All these 3 steps should be performed as an atomic operation
1873 	 * vis-a-vis similar sequence in the EMIF interrupt handler
1874 	 * for temperature events. Otherwise, there could be race
1875 	 * conditions that could result in incorrect EMIF timings for
1876 	 * a given frequency
1877 	 */
1878 	spin_lock_irqsave(&emif_lock, irq_state);
1879 
1880 	list_for_each_entry(emif, &device_list, node)
1881 		do_freq_pre_notify_handling(emif, new_freq);
1882 }
1883 
1884 static void do_freq_post_notify_handling(struct emif_data *emif)
1885 {
1886 	/*
1887 	 * Part of workaround for errata i728. See do_freq_update()
1888 	 * for more details
1889 	 */
1890 	if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
1891 		set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
1892 }
1893 
1894 /*
1895  * TODO: frequency notify handling should be hooked up to
1896  * clock framework as soon as the necessary support is
1897  * available in mainline kernel. This function is un-used
1898  * right now.
1899  */
1900 static void __attribute__((unused)) freq_post_notify_handling(void)
1901 {
1902 	struct emif_data *emif;
1903 
1904 	list_for_each_entry(emif, &device_list, node)
1905 		do_freq_post_notify_handling(emif);
1906 
1907 	/*
1908 	 * Lock is done in pre-notify handler. See freq_pre_notify_handling()
1909 	 * for more details
1910 	 */
1911 	spin_unlock_irqrestore(&emif_lock, irq_state);
1912 }
1913 
1914 #if defined(CONFIG_OF)
1915 static const struct of_device_id emif_of_match[] = {
1916 		{ .compatible = "ti,emif-4d" },
1917 		{ .compatible = "ti,emif-4d5" },
1918 		{},
1919 };
1920 MODULE_DEVICE_TABLE(of, emif_of_match);
1921 #endif
1922 
1923 static struct platform_driver emif_driver = {
1924 	.remove		= __exit_p(emif_remove),
1925 	.shutdown	= emif_shutdown,
1926 	.driver = {
1927 		.name = "emif",
1928 		.of_match_table = of_match_ptr(emif_of_match),
1929 	},
1930 };
1931 
1932 module_platform_driver_probe(emif_driver, emif_probe);
1933 
1934 MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
1935 MODULE_LICENSE("GPL");
1936 MODULE_ALIAS("platform:emif");
1937 MODULE_AUTHOR("Texas Instruments Inc");
1938