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