xref: /linux/arch/arm/mach-at91/pm.c (revision 18f90d372cf35b387663f1567de701e5393f6eb5)
1 /*
2  * arch/arm/mach-at91/pm.c
3  * AT91 Power Management
4  *
5  * Copyright (C) 2005 David Brownell
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 
13 #include <linux/genalloc.h>
14 #include <linux/io.h>
15 #include <linux/of_address.h>
16 #include <linux/of.h>
17 #include <linux/of_platform.h>
18 #include <linux/parser.h>
19 #include <linux/suspend.h>
20 
21 #include <linux/clk/at91_pmc.h>
22 
23 #include <asm/cacheflush.h>
24 #include <asm/fncpy.h>
25 #include <asm/system_misc.h>
26 #include <asm/suspend.h>
27 
28 #include "generic.h"
29 #include "pm.h"
30 
31 /*
32  * FIXME: this is needed to communicate between the pinctrl driver and
33  * the PM implementation in the machine. Possibly part of the PM
34  * implementation should be moved down into the pinctrl driver and get
35  * called as part of the generic suspend/resume path.
36  */
37 #ifdef CONFIG_PINCTRL_AT91
38 extern void at91_pinctrl_gpio_suspend(void);
39 extern void at91_pinctrl_gpio_resume(void);
40 #endif
41 
42 static const match_table_t pm_modes __initconst = {
43 	{ AT91_PM_STANDBY, "standby" },
44 	{ AT91_PM_ULP0, "ulp0" },
45 	{ AT91_PM_ULP1, "ulp1" },
46 	{ AT91_PM_BACKUP, "backup" },
47 	{ -1, NULL },
48 };
49 
50 static struct at91_pm_data pm_data = {
51 	.standby_mode = AT91_PM_STANDBY,
52 	.suspend_mode = AT91_PM_ULP0,
53 };
54 
55 #define at91_ramc_read(id, field) \
56 	__raw_readl(pm_data.ramc[id] + field)
57 
58 #define at91_ramc_write(id, field, value) \
59 	__raw_writel(value, pm_data.ramc[id] + field)
60 
61 static int at91_pm_valid_state(suspend_state_t state)
62 {
63 	switch (state) {
64 		case PM_SUSPEND_ON:
65 		case PM_SUSPEND_STANDBY:
66 		case PM_SUSPEND_MEM:
67 			return 1;
68 
69 		default:
70 			return 0;
71 	}
72 }
73 
74 static int canary = 0xA5A5A5A5;
75 
76 static struct at91_pm_bu {
77 	int suspended;
78 	unsigned long reserved;
79 	phys_addr_t canary;
80 	phys_addr_t resume;
81 } *pm_bu;
82 
83 struct wakeup_source_info {
84 	unsigned int pmc_fsmr_bit;
85 	unsigned int shdwc_mr_bit;
86 	bool set_polarity;
87 };
88 
89 static const struct wakeup_source_info ws_info[] = {
90 	{ .pmc_fsmr_bit = AT91_PMC_FSTT(10),	.set_polarity = true },
91 	{ .pmc_fsmr_bit = AT91_PMC_RTCAL,	.shdwc_mr_bit = BIT(17) },
92 	{ .pmc_fsmr_bit = AT91_PMC_USBAL },
93 	{ .pmc_fsmr_bit = AT91_PMC_SDMMC_CD },
94 };
95 
96 static const struct of_device_id sama5d2_ws_ids[] = {
97 	{ .compatible = "atmel,sama5d2-gem",		.data = &ws_info[0] },
98 	{ .compatible = "atmel,at91rm9200-rtc",		.data = &ws_info[1] },
99 	{ .compatible = "atmel,sama5d3-udc",		.data = &ws_info[2] },
100 	{ .compatible = "atmel,at91rm9200-ohci",	.data = &ws_info[2] },
101 	{ .compatible = "usb-ohci",			.data = &ws_info[2] },
102 	{ .compatible = "atmel,at91sam9g45-ehci",	.data = &ws_info[2] },
103 	{ .compatible = "usb-ehci",			.data = &ws_info[2] },
104 	{ .compatible = "atmel,sama5d2-sdhci",		.data = &ws_info[3] },
105 	{ /* sentinel */ }
106 };
107 
108 static int at91_pm_config_ws(unsigned int pm_mode, bool set)
109 {
110 	const struct wakeup_source_info *wsi;
111 	const struct of_device_id *match;
112 	struct platform_device *pdev;
113 	struct device_node *np;
114 	unsigned int mode = 0, polarity = 0, val = 0;
115 
116 	if (pm_mode != AT91_PM_ULP1)
117 		return 0;
118 
119 	if (!pm_data.pmc || !pm_data.shdwc)
120 		return -EPERM;
121 
122 	if (!set) {
123 		writel(mode, pm_data.pmc + AT91_PMC_FSMR);
124 		return 0;
125 	}
126 
127 	/* SHDWC.WUIR */
128 	val = readl(pm_data.shdwc + 0x0c);
129 	mode |= (val & 0x3ff);
130 	polarity |= ((val >> 16) & 0x3ff);
131 
132 	/* SHDWC.MR */
133 	val = readl(pm_data.shdwc + 0x04);
134 
135 	/* Loop through defined wakeup sources. */
136 	for_each_matching_node_and_match(np, sama5d2_ws_ids, &match) {
137 		pdev = of_find_device_by_node(np);
138 		if (!pdev)
139 			continue;
140 
141 		if (device_may_wakeup(&pdev->dev)) {
142 			wsi = match->data;
143 
144 			/* Check if enabled on SHDWC. */
145 			if (wsi->shdwc_mr_bit && !(val & wsi->shdwc_mr_bit))
146 				goto put_device;
147 
148 			mode |= wsi->pmc_fsmr_bit;
149 			if (wsi->set_polarity)
150 				polarity |= wsi->pmc_fsmr_bit;
151 		}
152 
153 put_device:
154 		put_device(&pdev->dev);
155 	}
156 
157 	if (mode) {
158 		writel(mode, pm_data.pmc + AT91_PMC_FSMR);
159 		writel(polarity, pm_data.pmc + AT91_PMC_FSPR);
160 	} else {
161 		pr_err("AT91: PM: no ULP1 wakeup sources found!");
162 	}
163 
164 	return mode ? 0 : -EPERM;
165 }
166 
167 /*
168  * Called after processes are frozen, but before we shutdown devices.
169  */
170 static int at91_pm_begin(suspend_state_t state)
171 {
172 	switch (state) {
173 	case PM_SUSPEND_MEM:
174 		pm_data.mode = pm_data.suspend_mode;
175 		break;
176 
177 	case PM_SUSPEND_STANDBY:
178 		pm_data.mode = pm_data.standby_mode;
179 		break;
180 
181 	default:
182 		pm_data.mode = -1;
183 	}
184 
185 	return at91_pm_config_ws(pm_data.mode, true);
186 }
187 
188 /*
189  * Verify that all the clocks are correct before entering
190  * slow-clock mode.
191  */
192 static int at91_pm_verify_clocks(void)
193 {
194 	unsigned long scsr;
195 	int i;
196 
197 	scsr = readl(pm_data.pmc + AT91_PMC_SCSR);
198 
199 	/* USB must not be using PLLB */
200 	if ((scsr & pm_data.uhp_udp_mask) != 0) {
201 		pr_err("AT91: PM - Suspend-to-RAM with USB still active\n");
202 		return 0;
203 	}
204 
205 	/* PCK0..PCK3 must be disabled, or configured to use clk32k */
206 	for (i = 0; i < 4; i++) {
207 		u32 css;
208 
209 		if ((scsr & (AT91_PMC_PCK0 << i)) == 0)
210 			continue;
211 		css = readl(pm_data.pmc + AT91_PMC_PCKR(i)) & AT91_PMC_CSS;
212 		if (css != AT91_PMC_CSS_SLOW) {
213 			pr_err("AT91: PM - Suspend-to-RAM with PCK%d src %d\n", i, css);
214 			return 0;
215 		}
216 	}
217 
218 	return 1;
219 }
220 
221 /*
222  * Call this from platform driver suspend() to see how deeply to suspend.
223  * For example, some controllers (like OHCI) need one of the PLL clocks
224  * in order to act as a wakeup source, and those are not available when
225  * going into slow clock mode.
226  *
227  * REVISIT: generalize as clk_will_be_available(clk)?  Other platforms have
228  * the very same problem (but not using at91 main_clk), and it'd be better
229  * to add one generic API rather than lots of platform-specific ones.
230  */
231 int at91_suspend_entering_slow_clock(void)
232 {
233 	return (pm_data.mode >= AT91_PM_ULP0);
234 }
235 EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
236 
237 static void (*at91_suspend_sram_fn)(struct at91_pm_data *);
238 extern void at91_pm_suspend_in_sram(struct at91_pm_data *pm_data);
239 extern u32 at91_pm_suspend_in_sram_sz;
240 
241 static int at91_suspend_finish(unsigned long val)
242 {
243 	flush_cache_all();
244 	outer_disable();
245 
246 	at91_suspend_sram_fn(&pm_data);
247 
248 	return 0;
249 }
250 
251 static void at91_pm_suspend(suspend_state_t state)
252 {
253 	if (pm_data.mode == AT91_PM_BACKUP) {
254 		pm_bu->suspended = 1;
255 
256 		cpu_suspend(0, at91_suspend_finish);
257 
258 		/* The SRAM is lost between suspend cycles */
259 		at91_suspend_sram_fn = fncpy(at91_suspend_sram_fn,
260 					     &at91_pm_suspend_in_sram,
261 					     at91_pm_suspend_in_sram_sz);
262 	} else {
263 		at91_suspend_finish(0);
264 	}
265 
266 	outer_resume();
267 }
268 
269 /*
270  * STANDBY mode has *all* drivers suspended; ignores irqs not marked as 'wakeup'
271  * event sources; and reduces DRAM power.  But otherwise it's identical to
272  * PM_SUSPEND_ON: cpu idle, and nothing fancy done with main or cpu clocks.
273  *
274  * AT91_PM_ULP0 is like STANDBY plus slow clock mode, so drivers must
275  * suspend more deeply, the master clock switches to the clk32k and turns off
276  * the main oscillator
277  *
278  * AT91_PM_BACKUP turns off the whole SoC after placing the DDR in self refresh
279  */
280 static int at91_pm_enter(suspend_state_t state)
281 {
282 #ifdef CONFIG_PINCTRL_AT91
283 	at91_pinctrl_gpio_suspend();
284 #endif
285 
286 	switch (state) {
287 	case PM_SUSPEND_MEM:
288 	case PM_SUSPEND_STANDBY:
289 		/*
290 		 * Ensure that clocks are in a valid state.
291 		 */
292 		if (pm_data.mode >= AT91_PM_ULP0 &&
293 		    !at91_pm_verify_clocks())
294 			goto error;
295 
296 		at91_pm_suspend(state);
297 
298 		break;
299 
300 	case PM_SUSPEND_ON:
301 		cpu_do_idle();
302 		break;
303 
304 	default:
305 		pr_debug("AT91: PM - bogus suspend state %d\n", state);
306 		goto error;
307 	}
308 
309 error:
310 #ifdef CONFIG_PINCTRL_AT91
311 	at91_pinctrl_gpio_resume();
312 #endif
313 	return 0;
314 }
315 
316 /*
317  * Called right prior to thawing processes.
318  */
319 static void at91_pm_end(void)
320 {
321 	at91_pm_config_ws(pm_data.mode, false);
322 }
323 
324 
325 static const struct platform_suspend_ops at91_pm_ops = {
326 	.valid	= at91_pm_valid_state,
327 	.begin	= at91_pm_begin,
328 	.enter	= at91_pm_enter,
329 	.end	= at91_pm_end,
330 };
331 
332 static struct platform_device at91_cpuidle_device = {
333 	.name = "cpuidle-at91",
334 };
335 
336 /*
337  * The AT91RM9200 goes into self-refresh mode with this command, and will
338  * terminate self-refresh automatically on the next SDRAM access.
339  *
340  * Self-refresh mode is exited as soon as a memory access is made, but we don't
341  * know for sure when that happens. However, we need to restore the low-power
342  * mode if it was enabled before going idle. Restoring low-power mode while
343  * still in self-refresh is "not recommended", but seems to work.
344  */
345 static void at91rm9200_standby(void)
346 {
347 	asm volatile(
348 		"b    1f\n\t"
349 		".align    5\n\t"
350 		"1:  mcr    p15, 0, %0, c7, c10, 4\n\t"
351 		"    str    %2, [%1, %3]\n\t"
352 		"    mcr    p15, 0, %0, c7, c0, 4\n\t"
353 		:
354 		: "r" (0), "r" (pm_data.ramc[0]),
355 		  "r" (1), "r" (AT91_MC_SDRAMC_SRR));
356 }
357 
358 /* We manage both DDRAM/SDRAM controllers, we need more than one value to
359  * remember.
360  */
361 static void at91_ddr_standby(void)
362 {
363 	/* Those two values allow us to delay self-refresh activation
364 	 * to the maximum. */
365 	u32 lpr0, lpr1 = 0;
366 	u32 mdr, saved_mdr0, saved_mdr1 = 0;
367 	u32 saved_lpr0, saved_lpr1 = 0;
368 
369 	/* LPDDR1 --> force DDR2 mode during self-refresh */
370 	saved_mdr0 = at91_ramc_read(0, AT91_DDRSDRC_MDR);
371 	if ((saved_mdr0 & AT91_DDRSDRC_MD) == AT91_DDRSDRC_MD_LOW_POWER_DDR) {
372 		mdr = saved_mdr0 & ~AT91_DDRSDRC_MD;
373 		mdr |= AT91_DDRSDRC_MD_DDR2;
374 		at91_ramc_write(0, AT91_DDRSDRC_MDR, mdr);
375 	}
376 
377 	if (pm_data.ramc[1]) {
378 		saved_lpr1 = at91_ramc_read(1, AT91_DDRSDRC_LPR);
379 		lpr1 = saved_lpr1 & ~AT91_DDRSDRC_LPCB;
380 		lpr1 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
381 		saved_mdr1 = at91_ramc_read(1, AT91_DDRSDRC_MDR);
382 		if ((saved_mdr1 & AT91_DDRSDRC_MD) == AT91_DDRSDRC_MD_LOW_POWER_DDR) {
383 			mdr = saved_mdr1 & ~AT91_DDRSDRC_MD;
384 			mdr |= AT91_DDRSDRC_MD_DDR2;
385 			at91_ramc_write(1, AT91_DDRSDRC_MDR, mdr);
386 		}
387 	}
388 
389 	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
390 	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
391 	lpr0 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
392 
393 	/* self-refresh mode now */
394 	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
395 	if (pm_data.ramc[1])
396 		at91_ramc_write(1, AT91_DDRSDRC_LPR, lpr1);
397 
398 	cpu_do_idle();
399 
400 	at91_ramc_write(0, AT91_DDRSDRC_MDR, saved_mdr0);
401 	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
402 	if (pm_data.ramc[1]) {
403 		at91_ramc_write(0, AT91_DDRSDRC_MDR, saved_mdr1);
404 		at91_ramc_write(1, AT91_DDRSDRC_LPR, saved_lpr1);
405 	}
406 }
407 
408 static void sama5d3_ddr_standby(void)
409 {
410 	u32 lpr0;
411 	u32 saved_lpr0;
412 
413 	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
414 	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
415 	lpr0 |= AT91_DDRSDRC_LPCB_POWER_DOWN;
416 
417 	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
418 
419 	cpu_do_idle();
420 
421 	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
422 }
423 
424 /* We manage both DDRAM/SDRAM controllers, we need more than one value to
425  * remember.
426  */
427 static void at91sam9_sdram_standby(void)
428 {
429 	u32 lpr0, lpr1 = 0;
430 	u32 saved_lpr0, saved_lpr1 = 0;
431 
432 	if (pm_data.ramc[1]) {
433 		saved_lpr1 = at91_ramc_read(1, AT91_SDRAMC_LPR);
434 		lpr1 = saved_lpr1 & ~AT91_SDRAMC_LPCB;
435 		lpr1 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
436 	}
437 
438 	saved_lpr0 = at91_ramc_read(0, AT91_SDRAMC_LPR);
439 	lpr0 = saved_lpr0 & ~AT91_SDRAMC_LPCB;
440 	lpr0 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
441 
442 	/* self-refresh mode now */
443 	at91_ramc_write(0, AT91_SDRAMC_LPR, lpr0);
444 	if (pm_data.ramc[1])
445 		at91_ramc_write(1, AT91_SDRAMC_LPR, lpr1);
446 
447 	cpu_do_idle();
448 
449 	at91_ramc_write(0, AT91_SDRAMC_LPR, saved_lpr0);
450 	if (pm_data.ramc[1])
451 		at91_ramc_write(1, AT91_SDRAMC_LPR, saved_lpr1);
452 }
453 
454 struct ramc_info {
455 	void (*idle)(void);
456 	unsigned int memctrl;
457 };
458 
459 static const struct ramc_info ramc_infos[] __initconst = {
460 	{ .idle = at91rm9200_standby, .memctrl = AT91_MEMCTRL_MC},
461 	{ .idle = at91sam9_sdram_standby, .memctrl = AT91_MEMCTRL_SDRAMC},
462 	{ .idle = at91_ddr_standby, .memctrl = AT91_MEMCTRL_DDRSDR},
463 	{ .idle = sama5d3_ddr_standby, .memctrl = AT91_MEMCTRL_DDRSDR},
464 };
465 
466 static const struct of_device_id ramc_ids[] __initconst = {
467 	{ .compatible = "atmel,at91rm9200-sdramc", .data = &ramc_infos[0] },
468 	{ .compatible = "atmel,at91sam9260-sdramc", .data = &ramc_infos[1] },
469 	{ .compatible = "atmel,at91sam9g45-ddramc", .data = &ramc_infos[2] },
470 	{ .compatible = "atmel,sama5d3-ddramc", .data = &ramc_infos[3] },
471 	{ /*sentinel*/ }
472 };
473 
474 static __init void at91_dt_ramc(void)
475 {
476 	struct device_node *np;
477 	const struct of_device_id *of_id;
478 	int idx = 0;
479 	void *standby = NULL;
480 	const struct ramc_info *ramc;
481 
482 	for_each_matching_node_and_match(np, ramc_ids, &of_id) {
483 		pm_data.ramc[idx] = of_iomap(np, 0);
484 		if (!pm_data.ramc[idx])
485 			panic(pr_fmt("unable to map ramc[%d] cpu registers\n"), idx);
486 
487 		ramc = of_id->data;
488 		if (!standby)
489 			standby = ramc->idle;
490 		pm_data.memctrl = ramc->memctrl;
491 
492 		idx++;
493 	}
494 
495 	if (!idx)
496 		panic(pr_fmt("unable to find compatible ram controller node in dtb\n"));
497 
498 	if (!standby) {
499 		pr_warn("ramc no standby function available\n");
500 		return;
501 	}
502 
503 	at91_cpuidle_device.dev.platform_data = standby;
504 }
505 
506 static void at91rm9200_idle(void)
507 {
508 	/*
509 	 * Disable the processor clock.  The processor will be automatically
510 	 * re-enabled by an interrupt or by a reset.
511 	 */
512 	writel(AT91_PMC_PCK, pm_data.pmc + AT91_PMC_SCDR);
513 }
514 
515 static void at91sam9_idle(void)
516 {
517 	writel(AT91_PMC_PCK, pm_data.pmc + AT91_PMC_SCDR);
518 	cpu_do_idle();
519 }
520 
521 static void __init at91_pm_sram_init(void)
522 {
523 	struct gen_pool *sram_pool;
524 	phys_addr_t sram_pbase;
525 	unsigned long sram_base;
526 	struct device_node *node;
527 	struct platform_device *pdev = NULL;
528 
529 	for_each_compatible_node(node, NULL, "mmio-sram") {
530 		pdev = of_find_device_by_node(node);
531 		if (pdev) {
532 			of_node_put(node);
533 			break;
534 		}
535 	}
536 
537 	if (!pdev) {
538 		pr_warn("%s: failed to find sram device!\n", __func__);
539 		return;
540 	}
541 
542 	sram_pool = gen_pool_get(&pdev->dev, NULL);
543 	if (!sram_pool) {
544 		pr_warn("%s: sram pool unavailable!\n", __func__);
545 		return;
546 	}
547 
548 	sram_base = gen_pool_alloc(sram_pool, at91_pm_suspend_in_sram_sz);
549 	if (!sram_base) {
550 		pr_warn("%s: unable to alloc sram!\n", __func__);
551 		return;
552 	}
553 
554 	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
555 	at91_suspend_sram_fn = __arm_ioremap_exec(sram_pbase,
556 					at91_pm_suspend_in_sram_sz, false);
557 	if (!at91_suspend_sram_fn) {
558 		pr_warn("SRAM: Could not map\n");
559 		return;
560 	}
561 
562 	/* Copy the pm suspend handler to SRAM */
563 	at91_suspend_sram_fn = fncpy(at91_suspend_sram_fn,
564 			&at91_pm_suspend_in_sram, at91_pm_suspend_in_sram_sz);
565 }
566 
567 static bool __init at91_is_pm_mode_active(int pm_mode)
568 {
569 	return (pm_data.standby_mode == pm_mode ||
570 		pm_data.suspend_mode == pm_mode);
571 }
572 
573 static int __init at91_pm_backup_init(void)
574 {
575 	struct gen_pool *sram_pool;
576 	struct device_node *np;
577 	struct platform_device *pdev = NULL;
578 	int ret = -ENODEV;
579 
580 	if (!at91_is_pm_mode_active(AT91_PM_BACKUP))
581 		return 0;
582 
583 	np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-sfrbu");
584 	if (!np) {
585 		pr_warn("%s: failed to find sfrbu!\n", __func__);
586 		return ret;
587 	}
588 
589 	pm_data.sfrbu = of_iomap(np, 0);
590 	of_node_put(np);
591 
592 	np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-securam");
593 	if (!np)
594 		goto securam_fail_no_ref_dev;
595 
596 	pdev = of_find_device_by_node(np);
597 	of_node_put(np);
598 	if (!pdev) {
599 		pr_warn("%s: failed to find securam device!\n", __func__);
600 		goto securam_fail_no_ref_dev;
601 	}
602 
603 	sram_pool = gen_pool_get(&pdev->dev, NULL);
604 	if (!sram_pool) {
605 		pr_warn("%s: securam pool unavailable!\n", __func__);
606 		goto securam_fail;
607 	}
608 
609 	pm_bu = (void *)gen_pool_alloc(sram_pool, sizeof(struct at91_pm_bu));
610 	if (!pm_bu) {
611 		pr_warn("%s: unable to alloc securam!\n", __func__);
612 		ret = -ENOMEM;
613 		goto securam_fail;
614 	}
615 
616 	pm_bu->suspended = 0;
617 	pm_bu->canary = __pa_symbol(&canary);
618 	pm_bu->resume = __pa_symbol(cpu_resume);
619 
620 	return 0;
621 
622 securam_fail:
623 	put_device(&pdev->dev);
624 securam_fail_no_ref_dev:
625 	iounmap(pm_data.sfrbu);
626 	pm_data.sfrbu = NULL;
627 	return ret;
628 }
629 
630 static void __init at91_pm_use_default_mode(int pm_mode)
631 {
632 	if (pm_mode != AT91_PM_ULP1 && pm_mode != AT91_PM_BACKUP)
633 		return;
634 
635 	if (pm_data.standby_mode == pm_mode)
636 		pm_data.standby_mode = AT91_PM_ULP0;
637 	if (pm_data.suspend_mode == pm_mode)
638 		pm_data.suspend_mode = AT91_PM_ULP0;
639 }
640 
641 static void __init at91_pm_modes_init(void)
642 {
643 	struct device_node *np;
644 	int ret;
645 
646 	if (!at91_is_pm_mode_active(AT91_PM_BACKUP) &&
647 	    !at91_is_pm_mode_active(AT91_PM_ULP1))
648 		return;
649 
650 	np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-shdwc");
651 	if (!np) {
652 		pr_warn("%s: failed to find shdwc!\n", __func__);
653 		goto ulp1_default;
654 	}
655 
656 	pm_data.shdwc = of_iomap(np, 0);
657 	of_node_put(np);
658 
659 	ret = at91_pm_backup_init();
660 	if (ret) {
661 		if (!at91_is_pm_mode_active(AT91_PM_ULP1))
662 			goto unmap;
663 		else
664 			goto backup_default;
665 	}
666 
667 	return;
668 
669 unmap:
670 	iounmap(pm_data.shdwc);
671 	pm_data.shdwc = NULL;
672 ulp1_default:
673 	at91_pm_use_default_mode(AT91_PM_ULP1);
674 backup_default:
675 	at91_pm_use_default_mode(AT91_PM_BACKUP);
676 }
677 
678 struct pmc_info {
679 	unsigned long uhp_udp_mask;
680 };
681 
682 static const struct pmc_info pmc_infos[] __initconst = {
683 	{ .uhp_udp_mask = AT91RM9200_PMC_UHP | AT91RM9200_PMC_UDP },
684 	{ .uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP },
685 	{ .uhp_udp_mask = AT91SAM926x_PMC_UHP },
686 	{ .uhp_udp_mask = 0 },
687 };
688 
689 static const struct of_device_id atmel_pmc_ids[] __initconst = {
690 	{ .compatible = "atmel,at91rm9200-pmc", .data = &pmc_infos[0] },
691 	{ .compatible = "atmel,at91sam9260-pmc", .data = &pmc_infos[1] },
692 	{ .compatible = "atmel,at91sam9261-pmc", .data = &pmc_infos[1] },
693 	{ .compatible = "atmel,at91sam9263-pmc", .data = &pmc_infos[1] },
694 	{ .compatible = "atmel,at91sam9g45-pmc", .data = &pmc_infos[2] },
695 	{ .compatible = "atmel,at91sam9n12-pmc", .data = &pmc_infos[1] },
696 	{ .compatible = "atmel,at91sam9rl-pmc", .data = &pmc_infos[3] },
697 	{ .compatible = "atmel,at91sam9x5-pmc", .data = &pmc_infos[1] },
698 	{ .compatible = "atmel,sama5d3-pmc", .data = &pmc_infos[1] },
699 	{ .compatible = "atmel,sama5d4-pmc", .data = &pmc_infos[1] },
700 	{ .compatible = "atmel,sama5d2-pmc", .data = &pmc_infos[1] },
701 	{ /* sentinel */ },
702 };
703 
704 static void __init at91_pm_init(void (*pm_idle)(void))
705 {
706 	struct device_node *pmc_np;
707 	const struct of_device_id *of_id;
708 	const struct pmc_info *pmc;
709 
710 	if (at91_cpuidle_device.dev.platform_data)
711 		platform_device_register(&at91_cpuidle_device);
712 
713 	pmc_np = of_find_matching_node_and_match(NULL, atmel_pmc_ids, &of_id);
714 	pm_data.pmc = of_iomap(pmc_np, 0);
715 	if (!pm_data.pmc) {
716 		pr_err("AT91: PM not supported, PMC not found\n");
717 		return;
718 	}
719 
720 	pmc = of_id->data;
721 	pm_data.uhp_udp_mask = pmc->uhp_udp_mask;
722 
723 	if (pm_idle)
724 		arm_pm_idle = pm_idle;
725 
726 	at91_pm_sram_init();
727 
728 	if (at91_suspend_sram_fn) {
729 		suspend_set_ops(&at91_pm_ops);
730 		pr_info("AT91: PM: standby: %s, suspend: %s\n",
731 			pm_modes[pm_data.standby_mode].pattern,
732 			pm_modes[pm_data.suspend_mode].pattern);
733 	} else {
734 		pr_info("AT91: PM not supported, due to no SRAM allocated\n");
735 	}
736 }
737 
738 void __init at91rm9200_pm_init(void)
739 {
740 	if (!IS_ENABLED(CONFIG_SOC_AT91RM9200))
741 		return;
742 
743 	at91_dt_ramc();
744 
745 	/*
746 	 * AT91RM9200 SDRAM low-power mode cannot be used with self-refresh.
747 	 */
748 	at91_ramc_write(0, AT91_MC_SDRAMC_LPR, 0);
749 
750 	at91_pm_init(at91rm9200_idle);
751 }
752 
753 void __init at91sam9_pm_init(void)
754 {
755 	if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
756 		return;
757 
758 	at91_dt_ramc();
759 	at91_pm_init(at91sam9_idle);
760 }
761 
762 void __init sama5_pm_init(void)
763 {
764 	if (!IS_ENABLED(CONFIG_SOC_SAMA5))
765 		return;
766 
767 	at91_dt_ramc();
768 	at91_pm_init(NULL);
769 }
770 
771 void __init sama5d2_pm_init(void)
772 {
773 	if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
774 		return;
775 
776 	at91_pm_modes_init();
777 	sama5_pm_init();
778 }
779 
780 static int __init at91_pm_modes_select(char *str)
781 {
782 	char *s;
783 	substring_t args[MAX_OPT_ARGS];
784 	int standby, suspend;
785 
786 	if (!str)
787 		return 0;
788 
789 	s = strsep(&str, ",");
790 	standby = match_token(s, pm_modes, args);
791 	if (standby < 0)
792 		return 0;
793 
794 	suspend = match_token(str, pm_modes, args);
795 	if (suspend < 0)
796 		return 0;
797 
798 	pm_data.standby_mode = standby;
799 	pm_data.suspend_mode = suspend;
800 
801 	return 0;
802 }
803 early_param("atmel.pm_modes", at91_pm_modes_select);
804