xref: /linux/drivers/memory/emif.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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/cleanup.h>
11 #include <linux/err.h>
12 #include <linux/kernel.h>
13 #include <linux/reboot.h>
14 #include <linux/platform_data/emif_plat.h>
15 #include <linux/io.h>
16 #include <linux/device.h>
17 #include <linux/platform_device.h>
18 #include <linux/interrupt.h>
19 #include <linux/slab.h>
20 #include <linux/of.h>
21 #include <linux/debugfs.h>
22 #include <linux/seq_file.h>
23 #include <linux/module.h>
24 #include <linux/list.h>
25 #include <linux/spinlock.h>
26 #include <linux/pm.h>
27 
28 #include "emif.h"
29 #include "jedec_ddr.h"
30 #include "of_memory.h"
31 
32 /**
33  * struct emif_data - Per device static data for driver's use
34  * @duplicate:			Whether the DDR devices attached to this EMIF
35  *				instance are exactly same as that on EMIF1. In
36  *				this case we can save some memory and processing
37  * @temperature_level:		Maximum temperature of LPDDR2 devices attached
38  *				to this EMIF - read from MR4 register. If there
39  *				are two devices attached to this EMIF, this
40  *				value is the maximum of the two temperature
41  *				levels.
42  * @node:			node in the device list
43  * @base:			base address of memory-mapped IO registers.
44  * @dev:			device pointer.
45  * @regs_cache:			An array of 'struct emif_regs' that stores
46  *				calculated register values for different
47  *				frequencies, to avoid re-calculating them on
48  *				each DVFS transition.
49  * @curr_regs:			The set of register values used in the last
50  *				frequency change (i.e. corresponding to the
51  *				frequency in effect at the moment)
52  * @plat_data:			Pointer to saved platform data.
53  * @debugfs_root:		dentry to the root folder for EMIF in debugfs
54  * @np_ddr:			Pointer to ddr device tree node
55  */
56 struct emif_data {
57 	u8				duplicate;
58 	u8				temperature_level;
59 	u8				lpmode;
60 	struct list_head		node;
61 	void __iomem			*base;
62 	struct device			*dev;
63 	struct emif_regs		*regs_cache[EMIF_MAX_NUM_FREQUENCIES];
64 	struct emif_regs		*curr_regs;
65 	struct emif_platform_data	*plat_data;
66 	struct dentry			*debugfs_root;
67 	struct device_node		*np_ddr;
68 };
69 
70 static struct emif_data *emif1;
71 static DEFINE_SPINLOCK(emif_lock);
72 static LIST_HEAD(device_list);
73 
74 static void do_emif_regdump_show(struct seq_file *s, struct emif_data *emif,
75 	struct emif_regs *regs)
76 {
77 	u32 type = emif->plat_data->device_info->type;
78 	u32 ip_rev = emif->plat_data->ip_rev;
79 
80 	seq_printf(s, "EMIF register cache dump for %dMHz\n",
81 		regs->freq/1000000);
82 
83 	seq_printf(s, "ref_ctrl_shdw\t: 0x%08x\n", regs->ref_ctrl_shdw);
84 	seq_printf(s, "sdram_tim1_shdw\t: 0x%08x\n", regs->sdram_tim1_shdw);
85 	seq_printf(s, "sdram_tim2_shdw\t: 0x%08x\n", regs->sdram_tim2_shdw);
86 	seq_printf(s, "sdram_tim3_shdw\t: 0x%08x\n", regs->sdram_tim3_shdw);
87 
88 	if (ip_rev == EMIF_4D) {
89 		seq_printf(s, "read_idle_ctrl_shdw_normal\t: 0x%08x\n",
90 			regs->read_idle_ctrl_shdw_normal);
91 		seq_printf(s, "read_idle_ctrl_shdw_volt_ramp\t: 0x%08x\n",
92 			regs->read_idle_ctrl_shdw_volt_ramp);
93 	} else if (ip_rev == EMIF_4D5) {
94 		seq_printf(s, "dll_calib_ctrl_shdw_normal\t: 0x%08x\n",
95 			regs->dll_calib_ctrl_shdw_normal);
96 		seq_printf(s, "dll_calib_ctrl_shdw_volt_ramp\t: 0x%08x\n",
97 			regs->dll_calib_ctrl_shdw_volt_ramp);
98 	}
99 
100 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4) {
101 		seq_printf(s, "ref_ctrl_shdw_derated\t: 0x%08x\n",
102 			regs->ref_ctrl_shdw_derated);
103 		seq_printf(s, "sdram_tim1_shdw_derated\t: 0x%08x\n",
104 			regs->sdram_tim1_shdw_derated);
105 		seq_printf(s, "sdram_tim3_shdw_derated\t: 0x%08x\n",
106 			regs->sdram_tim3_shdw_derated);
107 	}
108 }
109 
110 static int emif_regdump_show(struct seq_file *s, void *unused)
111 {
112 	struct emif_data	*emif	= s->private;
113 	struct emif_regs	**regs_cache;
114 	int			i;
115 
116 	if (emif->duplicate)
117 		regs_cache = emif1->regs_cache;
118 	else
119 		regs_cache = emif->regs_cache;
120 
121 	for (i = 0; i < EMIF_MAX_NUM_FREQUENCIES && regs_cache[i]; i++) {
122 		do_emif_regdump_show(s, emif, regs_cache[i]);
123 		seq_putc(s, '\n');
124 	}
125 
126 	return 0;
127 }
128 
129 DEFINE_SHOW_ATTRIBUTE(emif_regdump);
130 
131 static int emif_mr4_show(struct seq_file *s, void *unused)
132 {
133 	struct emif_data *emif = s->private;
134 
135 	seq_printf(s, "MR4=%d\n", emif->temperature_level);
136 	return 0;
137 }
138 
139 DEFINE_SHOW_ATTRIBUTE(emif_mr4);
140 
141 static void emif_debugfs_init(struct emif_data *emif)
142 {
143 	if (IS_ENABLED(CONFIG_DEBUG_FS)) {
144 		emif->debugfs_root = debugfs_create_dir(dev_name(emif->dev), NULL);
145 		debugfs_create_file("regcache_dump", S_IRUGO, emif->debugfs_root, emif,
146 				    &emif_regdump_fops);
147 		debugfs_create_file("mr4", S_IRUGO, emif->debugfs_root, emif,
148 				    &emif_mr4_fops);
149 	}
150 }
151 
152 static void emif_debugfs_exit(struct emif_data *emif)
153 {
154 	if (IS_ENABLED(CONFIG_DEBUG_FS)) {
155 		debugfs_remove_recursive(emif->debugfs_root);
156 		emif->debugfs_root = NULL;
157 	}
158 }
159 
160 /*
161  * Get bus width used by EMIF. Note that this may be different from the
162  * bus width of the DDR devices used. For instance two 16-bit DDR devices
163  * may be connected to a given CS of EMIF. In this case bus width as far
164  * as EMIF is concerned is 32, where as the DDR bus width is 16 bits.
165  */
166 static u32 get_emif_bus_width(struct emif_data *emif)
167 {
168 	u32		width;
169 	void __iomem	*base = emif->base;
170 
171 	width = (readl(base + EMIF_SDRAM_CONFIG) & NARROW_MODE_MASK)
172 			>> NARROW_MODE_SHIFT;
173 	width = width == 0 ? 32 : 16;
174 
175 	return width;
176 }
177 
178 static void set_lpmode(struct emif_data *emif, u8 lpmode)
179 {
180 	u32 temp;
181 	void __iomem *base = emif->base;
182 
183 	/*
184 	 * Workaround for errata i743 - LPDDR2 Power-Down State is Not
185 	 * Efficient
186 	 *
187 	 * i743 DESCRIPTION:
188 	 * The EMIF supports power-down state for low power. The EMIF
189 	 * automatically puts the SDRAM into power-down after the memory is
190 	 * not accessed for a defined number of cycles and the
191 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set to 0x4.
192 	 * As the EMIF supports automatic output impedance calibration, a ZQ
193 	 * calibration long command is issued every time it exits active
194 	 * power-down and precharge power-down modes. The EMIF waits and
195 	 * blocks any other command during this calibration.
196 	 * The EMIF does not allow selective disabling of ZQ calibration upon
197 	 * exit of power-down mode. Due to very short periods of power-down
198 	 * cycles, ZQ calibration overhead creates bandwidth issues and
199 	 * increases overall system power consumption. On the other hand,
200 	 * issuing ZQ calibration long commands when exiting self-refresh is
201 	 * still required.
202 	 *
203 	 * WORKAROUND
204 	 * Because there is no power consumption benefit of the power-down due
205 	 * to the calibration and there is a performance risk, the guideline
206 	 * is to not allow power-down state and, therefore, to not have set
207 	 * the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field to 0x4.
208 	 */
209 	if ((emif->plat_data->ip_rev == EMIF_4D) &&
210 	    (lpmode == EMIF_LP_MODE_PWR_DN)) {
211 		WARN_ONCE(1,
212 			  "REG_LP_MODE = LP_MODE_PWR_DN(4) is prohibited by erratum i743 switch to LP_MODE_SELF_REFRESH(2)\n");
213 		/* rollback LP_MODE to Self-refresh mode */
214 		lpmode = EMIF_LP_MODE_SELF_REFRESH;
215 	}
216 
217 	temp = readl(base + EMIF_POWER_MANAGEMENT_CONTROL);
218 	temp &= ~LP_MODE_MASK;
219 	temp |= (lpmode << LP_MODE_SHIFT);
220 	writel(temp, base + EMIF_POWER_MANAGEMENT_CONTROL);
221 }
222 
223 static void do_freq_update(void)
224 {
225 	struct emif_data *emif;
226 
227 	/*
228 	 * Workaround for errata i728: Disable LPMODE during FREQ_UPDATE
229 	 *
230 	 * i728 DESCRIPTION:
231 	 * The EMIF automatically puts the SDRAM into self-refresh mode
232 	 * after the EMIF has not performed accesses during
233 	 * EMIF_PWR_MGMT_CTRL[7:4] REG_SR_TIM number of DDR clock cycles
234 	 * and the EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE bit field is set
235 	 * to 0x2. If during a small window the following three events
236 	 * occur:
237 	 * - The SR_TIMING counter expires
238 	 * - And frequency change is requested
239 	 * - And OCP access is requested
240 	 * Then it causes instable clock on the DDR interface.
241 	 *
242 	 * WORKAROUND
243 	 * To avoid the occurrence of the three events, the workaround
244 	 * is to disable the self-refresh when requesting a frequency
245 	 * change. Before requesting a frequency change the software must
246 	 * program EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x0. When the
247 	 * frequency change has been done, the software can reprogram
248 	 * EMIF_PWR_MGMT_CTRL[10:8] REG_LP_MODE to 0x2
249 	 */
250 	list_for_each_entry(emif, &device_list, node) {
251 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
252 			set_lpmode(emif, EMIF_LP_MODE_DISABLE);
253 	}
254 
255 	/*
256 	 * TODO: Do FREQ_UPDATE here when an API
257 	 * is available for this as part of the new
258 	 * clock framework
259 	 */
260 
261 	list_for_each_entry(emif, &device_list, node) {
262 		if (emif->lpmode == EMIF_LP_MODE_SELF_REFRESH)
263 			set_lpmode(emif, EMIF_LP_MODE_SELF_REFRESH);
264 	}
265 }
266 
267 /* Find addressing table entry based on the device's type and density */
268 static const struct lpddr2_addressing *get_addressing_table(
269 	const struct ddr_device_info *device_info)
270 {
271 	u32		index, type, density;
272 
273 	type = device_info->type;
274 	density = device_info->density;
275 
276 	switch (type) {
277 	case DDR_TYPE_LPDDR2_S4:
278 		index = density - 1;
279 		break;
280 	case DDR_TYPE_LPDDR2_S2:
281 		switch (density) {
282 		case DDR_DENSITY_1Gb:
283 		case DDR_DENSITY_2Gb:
284 			index = density + 3;
285 			break;
286 		default:
287 			index = density - 1;
288 		}
289 		break;
290 	default:
291 		return NULL;
292 	}
293 
294 	return &lpddr2_jedec_addressing_table[index];
295 }
296 
297 static u32 get_zq_config_reg(const struct lpddr2_addressing *addressing,
298 		bool cs1_used, bool cal_resistors_per_cs)
299 {
300 	u32 zq = 0, val = 0;
301 
302 	val = EMIF_ZQCS_INTERVAL_US * 1000 / addressing->tREFI_ns;
303 	zq |= val << ZQ_REFINTERVAL_SHIFT;
304 
305 	val = DIV_ROUND_UP(T_ZQCL_DEFAULT_NS, T_ZQCS_DEFAULT_NS) - 1;
306 	zq |= val << ZQ_ZQCL_MULT_SHIFT;
307 
308 	val = DIV_ROUND_UP(T_ZQINIT_DEFAULT_NS, T_ZQCL_DEFAULT_NS) - 1;
309 	zq |= val << ZQ_ZQINIT_MULT_SHIFT;
310 
311 	zq |= ZQ_SFEXITEN_ENABLE << ZQ_SFEXITEN_SHIFT;
312 
313 	if (cal_resistors_per_cs)
314 		zq |= ZQ_DUALCALEN_ENABLE << ZQ_DUALCALEN_SHIFT;
315 	else
316 		zq |= ZQ_DUALCALEN_DISABLE << ZQ_DUALCALEN_SHIFT;
317 
318 	zq |= ZQ_CS0EN_MASK; /* CS0 is used for sure */
319 
320 	val = cs1_used ? 1 : 0;
321 	zq |= val << ZQ_CS1EN_SHIFT;
322 
323 	return zq;
324 }
325 
326 static u32 get_temp_alert_config(const struct lpddr2_addressing *addressing,
327 		const struct emif_custom_configs *custom_configs, bool cs1_used,
328 		u32 sdram_io_width, u32 emif_bus_width)
329 {
330 	u32 alert = 0, interval, devcnt;
331 
332 	if (custom_configs && (custom_configs->mask &
333 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL))
334 		interval = custom_configs->temp_alert_poll_interval_ms;
335 	else
336 		interval = TEMP_ALERT_POLL_INTERVAL_DEFAULT_MS;
337 
338 	interval *= 1000000;			/* Convert to ns */
339 	interval /= addressing->tREFI_ns;	/* Convert to refresh cycles */
340 	alert |= (interval << TA_REFINTERVAL_SHIFT);
341 
342 	/*
343 	 * sdram_io_width is in 'log2(x) - 1' form. Convert emif_bus_width
344 	 * also to this form and subtract to get TA_DEVCNT, which is
345 	 * in log2(x) form.
346 	 */
347 	emif_bus_width = __fls(emif_bus_width) - 1;
348 	devcnt = emif_bus_width - sdram_io_width;
349 	alert |= devcnt << TA_DEVCNT_SHIFT;
350 
351 	/* DEVWDT is in 'log2(x) - 3' form */
352 	alert |= (sdram_io_width - 2) << TA_DEVWDT_SHIFT;
353 
354 	alert |= 1 << TA_SFEXITEN_SHIFT;
355 	alert |= 1 << TA_CS0EN_SHIFT;
356 	alert |= (cs1_used ? 1 : 0) << TA_CS1EN_SHIFT;
357 
358 	return alert;
359 }
360 
361 static u32 get_pwr_mgmt_ctrl(u32 freq, struct emif_data *emif, u32 ip_rev)
362 {
363 	u32 pwr_mgmt_ctrl	= 0, timeout;
364 	u32 lpmode		= EMIF_LP_MODE_SELF_REFRESH;
365 	u32 timeout_perf	= EMIF_LP_MODE_TIMEOUT_PERFORMANCE;
366 	u32 timeout_pwr		= EMIF_LP_MODE_TIMEOUT_POWER;
367 	u32 freq_threshold	= EMIF_LP_MODE_FREQ_THRESHOLD;
368 	u32 mask;
369 	u8 shift;
370 
371 	struct emif_custom_configs *cust_cfgs = emif->plat_data->custom_configs;
372 
373 	if (cust_cfgs && (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE)) {
374 		lpmode		= cust_cfgs->lpmode;
375 		timeout_perf	= cust_cfgs->lpmode_timeout_performance;
376 		timeout_pwr	= cust_cfgs->lpmode_timeout_power;
377 		freq_threshold  = cust_cfgs->lpmode_freq_threshold;
378 	}
379 
380 	/* Timeout based on DDR frequency */
381 	timeout = freq >= freq_threshold ? timeout_perf : timeout_pwr;
382 
383 	/*
384 	 * The value to be set in register is "log2(timeout) - 3"
385 	 * if timeout < 16 load 0 in register
386 	 * if timeout is not a power of 2, round to next highest power of 2
387 	 */
388 	if (timeout < 16) {
389 		timeout = 0;
390 	} else {
391 		if (timeout & (timeout - 1))
392 			timeout <<= 1;
393 		timeout = __fls(timeout) - 3;
394 	}
395 
396 	switch (lpmode) {
397 	case EMIF_LP_MODE_CLOCK_STOP:
398 		shift = CS_TIM_SHIFT;
399 		mask = CS_TIM_MASK;
400 		break;
401 	case EMIF_LP_MODE_SELF_REFRESH:
402 		/* Workaround for errata i735 */
403 		if (timeout < 6)
404 			timeout = 6;
405 
406 		shift = SR_TIM_SHIFT;
407 		mask = SR_TIM_MASK;
408 		break;
409 	case EMIF_LP_MODE_PWR_DN:
410 		shift = PD_TIM_SHIFT;
411 		mask = PD_TIM_MASK;
412 		break;
413 	case EMIF_LP_MODE_DISABLE:
414 	default:
415 		mask = 0;
416 		shift = 0;
417 		break;
418 	}
419 	/* Round to maximum in case of overflow, BUT warn! */
420 	if (lpmode != EMIF_LP_MODE_DISABLE && timeout > mask >> shift) {
421 		pr_err("TIMEOUT Overflow - lpmode=%d perf=%d pwr=%d freq=%d\n",
422 		       lpmode,
423 		       timeout_perf,
424 		       timeout_pwr,
425 		       freq_threshold);
426 		WARN(1, "timeout=0x%02x greater than 0x%02x. Using max\n",
427 		     timeout, mask >> shift);
428 		timeout = mask >> shift;
429 	}
430 
431 	/* Setup required timing */
432 	pwr_mgmt_ctrl = (timeout << shift) & mask;
433 	/* setup a default mask for rest of the modes */
434 	pwr_mgmt_ctrl |= (SR_TIM_MASK | CS_TIM_MASK | PD_TIM_MASK) &
435 			  ~mask;
436 
437 	/* No CS_TIM in EMIF_4D5 */
438 	if (ip_rev == EMIF_4D5)
439 		pwr_mgmt_ctrl &= ~CS_TIM_MASK;
440 
441 	pwr_mgmt_ctrl |= lpmode << LP_MODE_SHIFT;
442 
443 	return pwr_mgmt_ctrl;
444 }
445 
446 /*
447  * Get the temperature level of the EMIF instance:
448  * Reads the MR4 register of attached SDRAM parts to find out the temperature
449  * level. If there are two parts attached(one on each CS), then the temperature
450  * level for the EMIF instance is the higher of the two temperatures.
451  */
452 static void get_temperature_level(struct emif_data *emif)
453 {
454 	u32		temp, temperature_level;
455 	void __iomem	*base;
456 
457 	base = emif->base;
458 
459 	/* Read mode register 4 */
460 	writel(DDR_MR4, base + EMIF_LPDDR2_MODE_REG_CONFIG);
461 	temperature_level = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
462 	temperature_level = (temperature_level & MR4_SDRAM_REF_RATE_MASK) >>
463 				MR4_SDRAM_REF_RATE_SHIFT;
464 
465 	if (emif->plat_data->device_info->cs1_used) {
466 		writel(DDR_MR4 | CS_MASK, base + EMIF_LPDDR2_MODE_REG_CONFIG);
467 		temp = readl(base + EMIF_LPDDR2_MODE_REG_DATA);
468 		temp = (temp & MR4_SDRAM_REF_RATE_MASK)
469 				>> MR4_SDRAM_REF_RATE_SHIFT;
470 		temperature_level = max(temp, temperature_level);
471 	}
472 
473 	/* treat everything less than nominal(3) in MR4 as nominal */
474 	if (unlikely(temperature_level < SDRAM_TEMP_NOMINAL))
475 		temperature_level = SDRAM_TEMP_NOMINAL;
476 
477 	/* if we get reserved value in MR4 persist with the existing value */
478 	if (likely(temperature_level != SDRAM_TEMP_RESERVED_4))
479 		emif->temperature_level = temperature_level;
480 }
481 
482 /*
483  * setup_temperature_sensitive_regs() - set the timings for temperature
484  * sensitive registers. This happens once at initialisation time based
485  * on the temperature at boot time and subsequently based on the temperature
486  * alert interrupt. Temperature alert can happen when the temperature
487  * increases or drops. So this function can have the effect of either
488  * derating the timings or going back to nominal values.
489  */
490 static void setup_temperature_sensitive_regs(struct emif_data *emif,
491 		struct emif_regs *regs)
492 {
493 	u32		tim1, tim3, ref_ctrl, type;
494 	void __iomem	*base = emif->base;
495 	u32		temperature;
496 
497 	type = emif->plat_data->device_info->type;
498 
499 	tim1 = regs->sdram_tim1_shdw;
500 	tim3 = regs->sdram_tim3_shdw;
501 	ref_ctrl = regs->ref_ctrl_shdw;
502 
503 	/* No de-rating for non-lpddr2 devices */
504 	if (type != DDR_TYPE_LPDDR2_S2 && type != DDR_TYPE_LPDDR2_S4)
505 		goto out;
506 
507 	temperature = emif->temperature_level;
508 	if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH) {
509 		ref_ctrl = regs->ref_ctrl_shdw_derated;
510 	} else if (temperature == SDRAM_TEMP_HIGH_DERATE_REFRESH_AND_TIMINGS) {
511 		tim1 = regs->sdram_tim1_shdw_derated;
512 		tim3 = regs->sdram_tim3_shdw_derated;
513 		ref_ctrl = regs->ref_ctrl_shdw_derated;
514 	}
515 
516 out:
517 	writel(tim1, base + EMIF_SDRAM_TIMING_1_SHDW);
518 	writel(tim3, base + EMIF_SDRAM_TIMING_3_SHDW);
519 	writel(ref_ctrl, base + EMIF_SDRAM_REFRESH_CTRL_SHDW);
520 }
521 
522 static irqreturn_t handle_temp_alert(void __iomem *base, struct emif_data *emif)
523 {
524 	u32		old_temp_level;
525 	irqreturn_t	ret;
526 	struct emif_custom_configs *custom_configs;
527 
528 	guard(spinlock_irqsave)(&emif_lock);
529 	old_temp_level = emif->temperature_level;
530 	get_temperature_level(emif);
531 
532 	if (unlikely(emif->temperature_level == old_temp_level)) {
533 		return IRQ_HANDLED;
534 	} else if (!emif->curr_regs) {
535 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
536 		return IRQ_HANDLED;
537 	}
538 
539 	custom_configs = emif->plat_data->custom_configs;
540 
541 	/*
542 	 * IF we detect higher than "nominal rating" from DDR sensor
543 	 * on an unsupported DDR part, shutdown system
544 	 */
545 	if (custom_configs && !(custom_configs->mask &
546 				EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART)) {
547 		if (emif->temperature_level >= SDRAM_TEMP_HIGH_DERATE_REFRESH) {
548 			dev_err(emif->dev,
549 				"%s:NOT Extended temperature capable memory. Converting MR4=0x%02x as shutdown event\n",
550 				__func__, emif->temperature_level);
551 			/*
552 			 * Temperature far too high - do kernel_power_off()
553 			 * from thread context
554 			 */
555 			emif->temperature_level = SDRAM_TEMP_VERY_HIGH_SHUTDOWN;
556 			return IRQ_WAKE_THREAD;
557 		}
558 	}
559 
560 	if (emif->temperature_level < old_temp_level ||
561 		emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
562 		/*
563 		 * Temperature coming down - defer handling to thread OR
564 		 * Temperature far too high - do kernel_power_off() from
565 		 * thread context
566 		 */
567 		ret = IRQ_WAKE_THREAD;
568 	} else {
569 		/* Temperature is going up - handle immediately */
570 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
571 		do_freq_update();
572 		ret = IRQ_HANDLED;
573 	}
574 
575 	return ret;
576 }
577 
578 static irqreturn_t emif_interrupt_handler(int irq, void *dev_id)
579 {
580 	u32			interrupts;
581 	struct emif_data	*emif = dev_id;
582 	void __iomem		*base = emif->base;
583 	struct device		*dev = emif->dev;
584 	irqreturn_t		ret = IRQ_HANDLED;
585 
586 	/* Save the status and clear it */
587 	interrupts = readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
588 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
589 
590 	/*
591 	 * Handle temperature alert
592 	 * Temperature alert should be same for all ports
593 	 * So, it's enough to process it only for one of the ports
594 	 */
595 	if (interrupts & TA_SYS_MASK)
596 		ret = handle_temp_alert(base, emif);
597 
598 	if (interrupts & ERR_SYS_MASK)
599 		dev_err(dev, "Access error from SYS port - %x\n", interrupts);
600 
601 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
602 		/* Save the status and clear it */
603 		interrupts = readl(base + EMIF_LL_OCP_INTERRUPT_STATUS);
604 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_STATUS);
605 
606 		if (interrupts & ERR_LL_MASK)
607 			dev_err(dev, "Access error from LL port - %x\n",
608 				interrupts);
609 	}
610 
611 	return ret;
612 }
613 
614 static irqreturn_t emif_threaded_isr(int irq, void *dev_id)
615 {
616 	struct emif_data	*emif = dev_id;
617 	unsigned long		irq_state;
618 
619 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN) {
620 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
621 
622 		/* If we have Power OFF ability, use it, else try restarting */
623 		if (kernel_can_power_off()) {
624 			kernel_power_off();
625 		} else {
626 			WARN(1, "FIXME: NO pm_power_off!!! trying restart\n");
627 			kernel_restart("SDRAM Over-temp Emergency restart");
628 		}
629 		return IRQ_HANDLED;
630 	}
631 
632 	spin_lock_irqsave(&emif_lock, irq_state);
633 
634 	if (emif->curr_regs) {
635 		setup_temperature_sensitive_regs(emif, emif->curr_regs);
636 		do_freq_update();
637 	} else {
638 		dev_err(emif->dev, "temperature alert before registers are calculated, not de-rating timings\n");
639 	}
640 
641 	spin_unlock_irqrestore(&emif_lock, irq_state);
642 
643 	return IRQ_HANDLED;
644 }
645 
646 static void clear_all_interrupts(struct emif_data *emif)
647 {
648 	void __iomem	*base = emif->base;
649 
650 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS),
651 		base + EMIF_SYSTEM_OCP_INTERRUPT_STATUS);
652 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
653 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_STATUS),
654 			base + EMIF_LL_OCP_INTERRUPT_STATUS);
655 }
656 
657 static void disable_and_clear_all_interrupts(struct emif_data *emif)
658 {
659 	void __iomem		*base = emif->base;
660 
661 	/* Disable all interrupts */
662 	writel(readl(base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET),
663 		base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_CLEAR);
664 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE)
665 		writel(readl(base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET),
666 			base + EMIF_LL_OCP_INTERRUPT_ENABLE_CLEAR);
667 
668 	/* Clear all interrupts */
669 	clear_all_interrupts(emif);
670 }
671 
672 static int setup_interrupts(struct emif_data *emif, u32 irq)
673 {
674 	u32		interrupts, type;
675 	void __iomem	*base = emif->base;
676 
677 	type = emif->plat_data->device_info->type;
678 
679 	clear_all_interrupts(emif);
680 
681 	/* Enable interrupts for SYS interface */
682 	interrupts = EN_ERR_SYS_MASK;
683 	if (type == DDR_TYPE_LPDDR2_S2 || type == DDR_TYPE_LPDDR2_S4)
684 		interrupts |= EN_TA_SYS_MASK;
685 	writel(interrupts, base + EMIF_SYSTEM_OCP_INTERRUPT_ENABLE_SET);
686 
687 	/* Enable interrupts for LL interface */
688 	if (emif->plat_data->hw_caps & EMIF_HW_CAPS_LL_INTERFACE) {
689 		/* TA need not be enabled for LL */
690 		interrupts = EN_ERR_LL_MASK;
691 		writel(interrupts, base + EMIF_LL_OCP_INTERRUPT_ENABLE_SET);
692 	}
693 
694 	/* setup IRQ handlers */
695 	return devm_request_threaded_irq(emif->dev, irq,
696 				    emif_interrupt_handler,
697 				    emif_threaded_isr,
698 				    0, dev_name(emif->dev),
699 				    emif);
700 
701 }
702 
703 static void emif_onetime_settings(struct emif_data *emif)
704 {
705 	u32				pwr_mgmt_ctrl, zq, temp_alert_cfg;
706 	void __iomem			*base = emif->base;
707 	const struct lpddr2_addressing	*addressing;
708 	const struct ddr_device_info	*device_info;
709 
710 	device_info = emif->plat_data->device_info;
711 	addressing = get_addressing_table(device_info);
712 
713 	/*
714 	 * Init power management settings
715 	 * We don't know the frequency yet. Use a high frequency
716 	 * value for a conservative timeout setting
717 	 */
718 	pwr_mgmt_ctrl = get_pwr_mgmt_ctrl(1000000000, emif,
719 			emif->plat_data->ip_rev);
720 	emif->lpmode = (pwr_mgmt_ctrl & LP_MODE_MASK) >> LP_MODE_SHIFT;
721 	writel(pwr_mgmt_ctrl, base + EMIF_POWER_MANAGEMENT_CONTROL);
722 
723 	/* Init ZQ calibration settings */
724 	zq = get_zq_config_reg(addressing, device_info->cs1_used,
725 		device_info->cal_resistors_per_cs);
726 	writel(zq, base + EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG);
727 
728 	/* Check temperature level temperature level*/
729 	get_temperature_level(emif);
730 	if (emif->temperature_level == SDRAM_TEMP_VERY_HIGH_SHUTDOWN)
731 		dev_emerg(emif->dev, "SDRAM temperature exceeds operating limit.. Needs shut down!!!\n");
732 
733 	/* Init temperature polling */
734 	temp_alert_cfg = get_temp_alert_config(addressing,
735 		emif->plat_data->custom_configs, device_info->cs1_used,
736 		device_info->io_width, get_emif_bus_width(emif));
737 	writel(temp_alert_cfg, base + EMIF_TEMPERATURE_ALERT_CONFIG);
738 
739 	/*
740 	 * Program external PHY control registers that are not frequency
741 	 * dependent
742 	 */
743 	if (emif->plat_data->phy_type != EMIF_PHY_TYPE_INTELLIPHY)
744 		return;
745 	writel(EMIF_EXT_PHY_CTRL_1_VAL, base + EMIF_EXT_PHY_CTRL_1_SHDW);
746 	writel(EMIF_EXT_PHY_CTRL_5_VAL, base + EMIF_EXT_PHY_CTRL_5_SHDW);
747 	writel(EMIF_EXT_PHY_CTRL_6_VAL, base + EMIF_EXT_PHY_CTRL_6_SHDW);
748 	writel(EMIF_EXT_PHY_CTRL_7_VAL, base + EMIF_EXT_PHY_CTRL_7_SHDW);
749 	writel(EMIF_EXT_PHY_CTRL_8_VAL, base + EMIF_EXT_PHY_CTRL_8_SHDW);
750 	writel(EMIF_EXT_PHY_CTRL_9_VAL, base + EMIF_EXT_PHY_CTRL_9_SHDW);
751 	writel(EMIF_EXT_PHY_CTRL_10_VAL, base + EMIF_EXT_PHY_CTRL_10_SHDW);
752 	writel(EMIF_EXT_PHY_CTRL_11_VAL, base + EMIF_EXT_PHY_CTRL_11_SHDW);
753 	writel(EMIF_EXT_PHY_CTRL_12_VAL, base + EMIF_EXT_PHY_CTRL_12_SHDW);
754 	writel(EMIF_EXT_PHY_CTRL_13_VAL, base + EMIF_EXT_PHY_CTRL_13_SHDW);
755 	writel(EMIF_EXT_PHY_CTRL_14_VAL, base + EMIF_EXT_PHY_CTRL_14_SHDW);
756 	writel(EMIF_EXT_PHY_CTRL_15_VAL, base + EMIF_EXT_PHY_CTRL_15_SHDW);
757 	writel(EMIF_EXT_PHY_CTRL_16_VAL, base + EMIF_EXT_PHY_CTRL_16_SHDW);
758 	writel(EMIF_EXT_PHY_CTRL_17_VAL, base + EMIF_EXT_PHY_CTRL_17_SHDW);
759 	writel(EMIF_EXT_PHY_CTRL_18_VAL, base + EMIF_EXT_PHY_CTRL_18_SHDW);
760 	writel(EMIF_EXT_PHY_CTRL_19_VAL, base + EMIF_EXT_PHY_CTRL_19_SHDW);
761 	writel(EMIF_EXT_PHY_CTRL_20_VAL, base + EMIF_EXT_PHY_CTRL_20_SHDW);
762 	writel(EMIF_EXT_PHY_CTRL_21_VAL, base + EMIF_EXT_PHY_CTRL_21_SHDW);
763 	writel(EMIF_EXT_PHY_CTRL_22_VAL, base + EMIF_EXT_PHY_CTRL_22_SHDW);
764 	writel(EMIF_EXT_PHY_CTRL_23_VAL, base + EMIF_EXT_PHY_CTRL_23_SHDW);
765 	writel(EMIF_EXT_PHY_CTRL_24_VAL, base + EMIF_EXT_PHY_CTRL_24_SHDW);
766 }
767 
768 static void get_default_timings(struct emif_data *emif)
769 {
770 	struct emif_platform_data *pd = emif->plat_data;
771 
772 	pd->timings		= lpddr2_jedec_timings;
773 	pd->timings_arr_size	= ARRAY_SIZE(lpddr2_jedec_timings);
774 
775 	dev_warn(emif->dev, "%s: using default timings\n", __func__);
776 }
777 
778 static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type,
779 		u32 ip_rev, struct device *dev)
780 {
781 	int valid;
782 
783 	valid = (type == DDR_TYPE_LPDDR2_S4 ||
784 			type == DDR_TYPE_LPDDR2_S2)
785 		&& (density >= DDR_DENSITY_64Mb
786 			&& density <= DDR_DENSITY_8Gb)
787 		&& (io_width >= DDR_IO_WIDTH_8
788 			&& io_width <= DDR_IO_WIDTH_32);
789 
790 	/* Combinations of EMIF and PHY revisions that we support today */
791 	switch (ip_rev) {
792 	case EMIF_4D:
793 		valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY);
794 		break;
795 	case EMIF_4D5:
796 		valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY);
797 		break;
798 	default:
799 		valid = 0;
800 	}
801 
802 	if (!valid)
803 		dev_err(dev, "%s: invalid DDR details\n", __func__);
804 	return valid;
805 }
806 
807 static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
808 		struct device *dev)
809 {
810 	int valid = 1;
811 
812 	if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) &&
813 		(cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE))
814 		valid = cust_cfgs->lpmode_freq_threshold &&
815 			cust_cfgs->lpmode_timeout_performance &&
816 			cust_cfgs->lpmode_timeout_power;
817 
818 	if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL)
819 		valid = valid && cust_cfgs->temp_alert_poll_interval_ms;
820 
821 	if (!valid)
822 		dev_warn(dev, "%s: invalid custom configs\n", __func__);
823 
824 	return valid;
825 }
826 
827 static void of_get_custom_configs(struct device_node *np_emif,
828 		struct emif_data *emif)
829 {
830 	struct emif_custom_configs	*cust_cfgs = NULL;
831 	int				len;
832 	const __be32			*lpmode, *poll_intvl;
833 
834 	lpmode = of_get_property(np_emif, "low-power-mode", &len);
835 	poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
836 
837 	if (lpmode || poll_intvl)
838 		cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
839 			GFP_KERNEL);
840 
841 	if (!cust_cfgs)
842 		return;
843 
844 	if (lpmode) {
845 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
846 		cust_cfgs->lpmode = be32_to_cpup(lpmode);
847 		of_property_read_u32(np_emif,
848 				"low-power-mode-timeout-performance",
849 				&cust_cfgs->lpmode_timeout_performance);
850 		of_property_read_u32(np_emif,
851 				"low-power-mode-timeout-power",
852 				&cust_cfgs->lpmode_timeout_power);
853 		of_property_read_u32(np_emif,
854 				"low-power-mode-freq-threshold",
855 				&cust_cfgs->lpmode_freq_threshold);
856 	}
857 
858 	if (poll_intvl) {
859 		cust_cfgs->mask |=
860 				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
861 		cust_cfgs->temp_alert_poll_interval_ms =
862 						be32_to_cpup(poll_intvl);
863 	}
864 
865 	if (of_property_read_bool(np_emif, "extended-temp-part"))
866 		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_EXTENDED_TEMP_PART;
867 
868 	if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
869 		devm_kfree(emif->dev, cust_cfgs);
870 		return;
871 	}
872 
873 	emif->plat_data->custom_configs = cust_cfgs;
874 }
875 
876 static void of_get_ddr_info(struct device_node *np_emif,
877 		struct device_node *np_ddr,
878 		struct ddr_device_info *dev_info)
879 {
880 	u32 density = 0, io_width = 0;
881 
882 	dev_info->cs1_used = of_property_read_bool(np_emif, "cs1-used");
883 	dev_info->cal_resistors_per_cs = of_property_read_bool(np_emif, "cal-resistor-per-cs");
884 
885 	if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s4"))
886 		dev_info->type = DDR_TYPE_LPDDR2_S4;
887 	else if (of_device_is_compatible(np_ddr, "jedec,lpddr2-s2"))
888 		dev_info->type = DDR_TYPE_LPDDR2_S2;
889 
890 	of_property_read_u32(np_ddr, "density", &density);
891 	of_property_read_u32(np_ddr, "io-width", &io_width);
892 
893 	/* Convert from density in Mb to the density encoding in jedc_ddr.h */
894 	if (density & (density - 1))
895 		dev_info->density = 0;
896 	else
897 		dev_info->density = __fls(density) - 5;
898 
899 	/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
900 	if (io_width & (io_width - 1))
901 		dev_info->io_width = 0;
902 	else
903 		dev_info->io_width = __fls(io_width) - 1;
904 }
905 
906 static struct emif_data *of_get_memory_device_details(
907 		struct device_node *np_emif, struct device *dev)
908 {
909 	struct emif_data		*emif = NULL;
910 	struct ddr_device_info		*dev_info = NULL;
911 	struct emif_platform_data	*pd = NULL;
912 	struct device_node		*np_ddr;
913 
914 	np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
915 	if (!np_ddr)
916 		goto error;
917 	emif	= devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
918 	pd	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
919 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
920 
921 	if (!emif || !pd || !dev_info) {
922 		dev_err(dev, "%s: Out of memory!!\n",
923 			__func__);
924 		goto error;
925 	}
926 
927 	emif->plat_data		= pd;
928 	pd->device_info		= dev_info;
929 	emif->dev		= dev;
930 	emif->np_ddr		= np_ddr;
931 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
932 
933 	if (of_device_is_compatible(np_emif, "ti,emif-4d"))
934 		emif->plat_data->ip_rev = EMIF_4D;
935 	else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
936 		emif->plat_data->ip_rev = EMIF_4D5;
937 
938 	of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
939 
940 	if (of_property_read_bool(np_emif, "hw-caps-ll-interface"))
941 		pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
942 
943 	of_get_ddr_info(np_emif, np_ddr, dev_info);
944 	if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
945 			pd->device_info->io_width, pd->phy_type, pd->ip_rev,
946 			emif->dev)) {
947 		dev_err(dev, "%s: invalid device data!!\n", __func__);
948 		goto error;
949 	}
950 	/*
951 	 * For EMIF instances other than EMIF1 see if the devices connected
952 	 * are exactly same as on EMIF1(which is typically the case). If so,
953 	 * mark it as a duplicate of EMIF1. This will save some memory and
954 	 * computation.
955 	 */
956 	if (emif1 && emif1->np_ddr == np_ddr) {
957 		emif->duplicate = true;
958 		goto out;
959 	} else if (emif1) {
960 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
961 			__func__);
962 	}
963 
964 	of_get_custom_configs(np_emif, emif);
965 	emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
966 					emif->plat_data->device_info->type,
967 					&emif->plat_data->timings_arr_size);
968 
969 	emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
970 	goto out;
971 
972 error:
973 	return NULL;
974 out:
975 	return emif;
976 }
977 
978 static struct emif_data *get_device_details(
979 		struct platform_device *pdev)
980 {
981 	u32				size;
982 	struct emif_data		*emif = NULL;
983 	struct ddr_device_info		*dev_info;
984 	struct emif_custom_configs	*cust_cfgs;
985 	struct emif_platform_data	*pd;
986 	struct device			*dev;
987 	void				*temp;
988 
989 	pd = pdev->dev.platform_data;
990 	dev = &pdev->dev;
991 
992 	if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type,
993 			pd->device_info->density, pd->device_info->io_width,
994 			pd->phy_type, pd->ip_rev, dev))) {
995 		dev_err(dev, "%s: invalid device data\n", __func__);
996 		goto error;
997 	}
998 
999 	emif	= devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL);
1000 	temp	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
1001 	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
1002 
1003 	if (!emif || !temp || !dev_info)
1004 		goto error;
1005 
1006 	memcpy(temp, pd, sizeof(*pd));
1007 	pd = temp;
1008 	memcpy(dev_info, pd->device_info, sizeof(*dev_info));
1009 
1010 	pd->device_info		= dev_info;
1011 	emif->plat_data		= pd;
1012 	emif->dev		= dev;
1013 	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
1014 
1015 	/*
1016 	 * For EMIF instances other than EMIF1 see if the devices connected
1017 	 * are exactly same as on EMIF1(which is typically the case). If so,
1018 	 * mark it as a duplicate of EMIF1 and skip copying timings data.
1019 	 * This will save some memory and some computation later.
1020 	 */
1021 	emif->duplicate = emif1 && (memcmp(dev_info,
1022 		emif1->plat_data->device_info,
1023 		sizeof(struct ddr_device_info)) == 0);
1024 
1025 	if (emif->duplicate) {
1026 		pd->timings = NULL;
1027 		pd->min_tck = NULL;
1028 		goto out;
1029 	} else if (emif1) {
1030 		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
1031 			__func__);
1032 	}
1033 
1034 	/*
1035 	 * Copy custom configs - ignore allocation error, if any, as
1036 	 * custom_configs is not very critical
1037 	 */
1038 	cust_cfgs = pd->custom_configs;
1039 	if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) {
1040 		temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL);
1041 		if (temp)
1042 			memcpy(temp, cust_cfgs, sizeof(*cust_cfgs));
1043 		pd->custom_configs = temp;
1044 	}
1045 
1046 	/*
1047 	 * Copy timings and min-tck values from platform data. If it is not
1048 	 * available or if memory allocation fails, use JEDEC defaults
1049 	 */
1050 	size = sizeof(struct lpddr2_timings) * pd->timings_arr_size;
1051 	if (pd->timings) {
1052 		temp = devm_kzalloc(dev, size, GFP_KERNEL);
1053 		if (temp) {
1054 			memcpy(temp, pd->timings, size);
1055 			pd->timings = temp;
1056 		} else {
1057 			get_default_timings(emif);
1058 		}
1059 	} else {
1060 		get_default_timings(emif);
1061 	}
1062 
1063 	if (pd->min_tck) {
1064 		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
1065 		if (temp) {
1066 			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
1067 			pd->min_tck = temp;
1068 		} else {
1069 			pd->min_tck = &lpddr2_jedec_min_tck;
1070 		}
1071 	} else {
1072 		pd->min_tck = &lpddr2_jedec_min_tck;
1073 	}
1074 
1075 out:
1076 	return emif;
1077 
1078 error:
1079 	return NULL;
1080 }
1081 
1082 static int emif_probe(struct platform_device *pdev)
1083 {
1084 	struct emif_data	*emif;
1085 	int			irq, ret;
1086 
1087 	if (pdev->dev.of_node)
1088 		emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
1089 	else
1090 		emif = get_device_details(pdev);
1091 
1092 	if (!emif) {
1093 		pr_err("%s: error getting device data\n", __func__);
1094 		goto error;
1095 	}
1096 
1097 	list_add(&emif->node, &device_list);
1098 
1099 	/* Save pointers to each other in emif and device structures */
1100 	emif->dev = &pdev->dev;
1101 	platform_set_drvdata(pdev, emif);
1102 
1103 	emif->base = devm_platform_ioremap_resource(pdev, 0);
1104 	if (IS_ERR(emif->base))
1105 		goto error;
1106 
1107 	irq = platform_get_irq(pdev, 0);
1108 	if (irq < 0)
1109 		goto error;
1110 
1111 	emif_onetime_settings(emif);
1112 	emif_debugfs_init(emif);
1113 	disable_and_clear_all_interrupts(emif);
1114 	ret = setup_interrupts(emif, irq);
1115 	if (ret)
1116 		goto error;
1117 
1118 	/* One-time actions taken on probing the first device */
1119 	if (!emif1) {
1120 		emif1 = emif;
1121 
1122 		/*
1123 		 * TODO: register notifiers for frequency and voltage
1124 		 * change here once the respective frameworks are
1125 		 * available
1126 		 */
1127 	}
1128 
1129 	dev_info(&pdev->dev, "%s: device configured with addr = %p and IRQ%d\n",
1130 		__func__, emif->base, irq);
1131 
1132 	return 0;
1133 error:
1134 	return -ENODEV;
1135 }
1136 
1137 static void emif_remove(struct platform_device *pdev)
1138 {
1139 	struct emif_data *emif = platform_get_drvdata(pdev);
1140 
1141 	emif_debugfs_exit(emif);
1142 }
1143 
1144 static void emif_shutdown(struct platform_device *pdev)
1145 {
1146 	struct emif_data	*emif = platform_get_drvdata(pdev);
1147 
1148 	disable_and_clear_all_interrupts(emif);
1149 }
1150 
1151 #if defined(CONFIG_OF)
1152 static const struct of_device_id emif_of_match[] = {
1153 		{ .compatible = "ti,emif-4d" },
1154 		{ .compatible = "ti,emif-4d5" },
1155 		{},
1156 };
1157 MODULE_DEVICE_TABLE(of, emif_of_match);
1158 #endif
1159 
1160 static struct platform_driver emif_driver = {
1161 	.probe		= emif_probe,
1162 	.remove_new	= emif_remove,
1163 	.shutdown	= emif_shutdown,
1164 	.driver = {
1165 		.name = "emif",
1166 		.of_match_table = of_match_ptr(emif_of_match),
1167 	},
1168 };
1169 
1170 module_platform_driver(emif_driver);
1171 
1172 MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver");
1173 MODULE_LICENSE("GPL");
1174 MODULE_ALIAS("platform:emif");
1175 MODULE_AUTHOR("Texas Instruments Inc");
1176