xref: /openbmc/linux/arch/arm/mach-at91/pm.c (revision ae213c44)
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 struct at91_soc_pm {
43 	int (*config_shdwc_ws)(void __iomem *shdwc, u32 *mode, u32 *polarity);
44 	int (*config_pmc_ws)(void __iomem *pmc, u32 mode, u32 polarity);
45 	const struct of_device_id *ws_ids;
46 	struct at91_pm_data data;
47 };
48 
49 static struct at91_soc_pm soc_pm = {
50 	.data = {
51 		.standby_mode = AT91_PM_STANDBY,
52 		.suspend_mode = AT91_PM_ULP0,
53 	},
54 };
55 
56 static const match_table_t pm_modes __initconst = {
57 	{ AT91_PM_STANDBY, "standby" },
58 	{ AT91_PM_ULP0, "ulp0" },
59 	{ AT91_PM_ULP1, "ulp1" },
60 	{ AT91_PM_BACKUP, "backup" },
61 	{ -1, NULL },
62 };
63 
64 #define at91_ramc_read(id, field) \
65 	__raw_readl(soc_pm.data.ramc[id] + field)
66 
67 #define at91_ramc_write(id, field, value) \
68 	__raw_writel(value, soc_pm.data.ramc[id] + field)
69 
70 static int at91_pm_valid_state(suspend_state_t state)
71 {
72 	switch (state) {
73 		case PM_SUSPEND_ON:
74 		case PM_SUSPEND_STANDBY:
75 		case PM_SUSPEND_MEM:
76 			return 1;
77 
78 		default:
79 			return 0;
80 	}
81 }
82 
83 static int canary = 0xA5A5A5A5;
84 
85 static struct at91_pm_bu {
86 	int suspended;
87 	unsigned long reserved;
88 	phys_addr_t canary;
89 	phys_addr_t resume;
90 } *pm_bu;
91 
92 struct wakeup_source_info {
93 	unsigned int pmc_fsmr_bit;
94 	unsigned int shdwc_mr_bit;
95 	bool set_polarity;
96 };
97 
98 static const struct wakeup_source_info ws_info[] = {
99 	{ .pmc_fsmr_bit = AT91_PMC_FSTT(10),	.set_polarity = true },
100 	{ .pmc_fsmr_bit = AT91_PMC_RTCAL,	.shdwc_mr_bit = BIT(17) },
101 	{ .pmc_fsmr_bit = AT91_PMC_USBAL },
102 	{ .pmc_fsmr_bit = AT91_PMC_SDMMC_CD },
103 	{ .pmc_fsmr_bit = AT91_PMC_RTTAL },
104 	{ .pmc_fsmr_bit = AT91_PMC_RXLP_MCE },
105 };
106 
107 static const struct of_device_id sama5d2_ws_ids[] = {
108 	{ .compatible = "atmel,sama5d2-gem",		.data = &ws_info[0] },
109 	{ .compatible = "atmel,at91rm9200-rtc",		.data = &ws_info[1] },
110 	{ .compatible = "atmel,sama5d3-udc",		.data = &ws_info[2] },
111 	{ .compatible = "atmel,at91rm9200-ohci",	.data = &ws_info[2] },
112 	{ .compatible = "usb-ohci",			.data = &ws_info[2] },
113 	{ .compatible = "atmel,at91sam9g45-ehci",	.data = &ws_info[2] },
114 	{ .compatible = "usb-ehci",			.data = &ws_info[2] },
115 	{ .compatible = "atmel,sama5d2-sdhci",		.data = &ws_info[3] },
116 	{ /* sentinel */ }
117 };
118 
119 static const struct of_device_id sam9x60_ws_ids[] = {
120 	{ .compatible = "atmel,at91sam9x5-rtc",		.data = &ws_info[1] },
121 	{ .compatible = "atmel,at91rm9200-ohci",	.data = &ws_info[2] },
122 	{ .compatible = "usb-ohci",			.data = &ws_info[2] },
123 	{ .compatible = "atmel,at91sam9g45-ehci",	.data = &ws_info[2] },
124 	{ .compatible = "usb-ehci",			.data = &ws_info[2] },
125 	{ .compatible = "atmel,at91sam9260-rtt",	.data = &ws_info[4] },
126 	{ .compatible = "cdns,sam9x60-macb",		.data = &ws_info[5] },
127 	{ /* sentinel */ }
128 };
129 
130 static int at91_pm_config_ws(unsigned int pm_mode, bool set)
131 {
132 	const struct wakeup_source_info *wsi;
133 	const struct of_device_id *match;
134 	struct platform_device *pdev;
135 	struct device_node *np;
136 	unsigned int mode = 0, polarity = 0, val = 0;
137 
138 	if (pm_mode != AT91_PM_ULP1)
139 		return 0;
140 
141 	if (!soc_pm.data.pmc || !soc_pm.data.shdwc || !soc_pm.ws_ids)
142 		return -EPERM;
143 
144 	if (!set) {
145 		writel(mode, soc_pm.data.pmc + AT91_PMC_FSMR);
146 		return 0;
147 	}
148 
149 	if (soc_pm.config_shdwc_ws)
150 		soc_pm.config_shdwc_ws(soc_pm.data.shdwc, &mode, &polarity);
151 
152 	/* SHDWC.MR */
153 	val = readl(soc_pm.data.shdwc + 0x04);
154 
155 	/* Loop through defined wakeup sources. */
156 	for_each_matching_node_and_match(np, soc_pm.ws_ids, &match) {
157 		pdev = of_find_device_by_node(np);
158 		if (!pdev)
159 			continue;
160 
161 		if (device_may_wakeup(&pdev->dev)) {
162 			wsi = match->data;
163 
164 			/* Check if enabled on SHDWC. */
165 			if (wsi->shdwc_mr_bit && !(val & wsi->shdwc_mr_bit))
166 				goto put_device;
167 
168 			mode |= wsi->pmc_fsmr_bit;
169 			if (wsi->set_polarity)
170 				polarity |= wsi->pmc_fsmr_bit;
171 		}
172 
173 put_device:
174 		put_device(&pdev->dev);
175 	}
176 
177 	if (mode) {
178 		if (soc_pm.config_pmc_ws)
179 			soc_pm.config_pmc_ws(soc_pm.data.pmc, mode, polarity);
180 	} else {
181 		pr_err("AT91: PM: no ULP1 wakeup sources found!");
182 	}
183 
184 	return mode ? 0 : -EPERM;
185 }
186 
187 static int at91_sama5d2_config_shdwc_ws(void __iomem *shdwc, u32 *mode,
188 					u32 *polarity)
189 {
190 	u32 val;
191 
192 	/* SHDWC.WUIR */
193 	val = readl(shdwc + 0x0c);
194 	*mode |= (val & 0x3ff);
195 	*polarity |= ((val >> 16) & 0x3ff);
196 
197 	return 0;
198 }
199 
200 static int at91_sama5d2_config_pmc_ws(void __iomem *pmc, u32 mode, u32 polarity)
201 {
202 	writel(mode, pmc + AT91_PMC_FSMR);
203 	writel(polarity, pmc + AT91_PMC_FSPR);
204 
205 	return 0;
206 }
207 
208 static int at91_sam9x60_config_pmc_ws(void __iomem *pmc, u32 mode, u32 polarity)
209 {
210 	writel(mode, pmc + AT91_PMC_FSMR);
211 
212 	return 0;
213 }
214 
215 /*
216  * Called after processes are frozen, but before we shutdown devices.
217  */
218 static int at91_pm_begin(suspend_state_t state)
219 {
220 	switch (state) {
221 	case PM_SUSPEND_MEM:
222 		soc_pm.data.mode = soc_pm.data.suspend_mode;
223 		break;
224 
225 	case PM_SUSPEND_STANDBY:
226 		soc_pm.data.mode = soc_pm.data.standby_mode;
227 		break;
228 
229 	default:
230 		soc_pm.data.mode = -1;
231 	}
232 
233 	return at91_pm_config_ws(soc_pm.data.mode, true);
234 }
235 
236 /*
237  * Verify that all the clocks are correct before entering
238  * slow-clock mode.
239  */
240 static int at91_pm_verify_clocks(void)
241 {
242 	unsigned long scsr;
243 	int i;
244 
245 	scsr = readl(soc_pm.data.pmc + AT91_PMC_SCSR);
246 
247 	/* USB must not be using PLLB */
248 	if ((scsr & soc_pm.data.uhp_udp_mask) != 0) {
249 		pr_err("AT91: PM - Suspend-to-RAM with USB still active\n");
250 		return 0;
251 	}
252 
253 	/* PCK0..PCK3 must be disabled, or configured to use clk32k */
254 	for (i = 0; i < 4; i++) {
255 		u32 css;
256 
257 		if ((scsr & (AT91_PMC_PCK0 << i)) == 0)
258 			continue;
259 		css = readl(soc_pm.data.pmc + AT91_PMC_PCKR(i)) & AT91_PMC_CSS;
260 		if (css != AT91_PMC_CSS_SLOW) {
261 			pr_err("AT91: PM - Suspend-to-RAM with PCK%d src %d\n", i, css);
262 			return 0;
263 		}
264 	}
265 
266 	return 1;
267 }
268 
269 /*
270  * Call this from platform driver suspend() to see how deeply to suspend.
271  * For example, some controllers (like OHCI) need one of the PLL clocks
272  * in order to act as a wakeup source, and those are not available when
273  * going into slow clock mode.
274  *
275  * REVISIT: generalize as clk_will_be_available(clk)?  Other platforms have
276  * the very same problem (but not using at91 main_clk), and it'd be better
277  * to add one generic API rather than lots of platform-specific ones.
278  */
279 int at91_suspend_entering_slow_clock(void)
280 {
281 	return (soc_pm.data.mode >= AT91_PM_ULP0);
282 }
283 EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
284 
285 static void (*at91_suspend_sram_fn)(struct at91_pm_data *);
286 extern void at91_pm_suspend_in_sram(struct at91_pm_data *pm_data);
287 extern u32 at91_pm_suspend_in_sram_sz;
288 
289 static int at91_suspend_finish(unsigned long val)
290 {
291 	flush_cache_all();
292 	outer_disable();
293 
294 	at91_suspend_sram_fn(&soc_pm.data);
295 
296 	return 0;
297 }
298 
299 static void at91_pm_suspend(suspend_state_t state)
300 {
301 	if (soc_pm.data.mode == AT91_PM_BACKUP) {
302 		pm_bu->suspended = 1;
303 
304 		cpu_suspend(0, at91_suspend_finish);
305 
306 		/* The SRAM is lost between suspend cycles */
307 		at91_suspend_sram_fn = fncpy(at91_suspend_sram_fn,
308 					     &at91_pm_suspend_in_sram,
309 					     at91_pm_suspend_in_sram_sz);
310 	} else {
311 		at91_suspend_finish(0);
312 	}
313 
314 	outer_resume();
315 }
316 
317 /*
318  * STANDBY mode has *all* drivers suspended; ignores irqs not marked as 'wakeup'
319  * event sources; and reduces DRAM power.  But otherwise it's identical to
320  * PM_SUSPEND_ON: cpu idle, and nothing fancy done with main or cpu clocks.
321  *
322  * AT91_PM_ULP0 is like STANDBY plus slow clock mode, so drivers must
323  * suspend more deeply, the master clock switches to the clk32k and turns off
324  * the main oscillator
325  *
326  * AT91_PM_BACKUP turns off the whole SoC after placing the DDR in self refresh
327  */
328 static int at91_pm_enter(suspend_state_t state)
329 {
330 #ifdef CONFIG_PINCTRL_AT91
331 	at91_pinctrl_gpio_suspend();
332 #endif
333 
334 	switch (state) {
335 	case PM_SUSPEND_MEM:
336 	case PM_SUSPEND_STANDBY:
337 		/*
338 		 * Ensure that clocks are in a valid state.
339 		 */
340 		if (soc_pm.data.mode >= AT91_PM_ULP0 &&
341 		    !at91_pm_verify_clocks())
342 			goto error;
343 
344 		at91_pm_suspend(state);
345 
346 		break;
347 
348 	case PM_SUSPEND_ON:
349 		cpu_do_idle();
350 		break;
351 
352 	default:
353 		pr_debug("AT91: PM - bogus suspend state %d\n", state);
354 		goto error;
355 	}
356 
357 error:
358 #ifdef CONFIG_PINCTRL_AT91
359 	at91_pinctrl_gpio_resume();
360 #endif
361 	return 0;
362 }
363 
364 /*
365  * Called right prior to thawing processes.
366  */
367 static void at91_pm_end(void)
368 {
369 	at91_pm_config_ws(soc_pm.data.mode, false);
370 }
371 
372 
373 static const struct platform_suspend_ops at91_pm_ops = {
374 	.valid	= at91_pm_valid_state,
375 	.begin	= at91_pm_begin,
376 	.enter	= at91_pm_enter,
377 	.end	= at91_pm_end,
378 };
379 
380 static struct platform_device at91_cpuidle_device = {
381 	.name = "cpuidle-at91",
382 };
383 
384 /*
385  * The AT91RM9200 goes into self-refresh mode with this command, and will
386  * terminate self-refresh automatically on the next SDRAM access.
387  *
388  * Self-refresh mode is exited as soon as a memory access is made, but we don't
389  * know for sure when that happens. However, we need to restore the low-power
390  * mode if it was enabled before going idle. Restoring low-power mode while
391  * still in self-refresh is "not recommended", but seems to work.
392  */
393 static void at91rm9200_standby(void)
394 {
395 	asm volatile(
396 		"b    1f\n\t"
397 		".align    5\n\t"
398 		"1:  mcr    p15, 0, %0, c7, c10, 4\n\t"
399 		"    str    %2, [%1, %3]\n\t"
400 		"    mcr    p15, 0, %0, c7, c0, 4\n\t"
401 		:
402 		: "r" (0), "r" (soc_pm.data.ramc[0]),
403 		  "r" (1), "r" (AT91_MC_SDRAMC_SRR));
404 }
405 
406 /* We manage both DDRAM/SDRAM controllers, we need more than one value to
407  * remember.
408  */
409 static void at91_ddr_standby(void)
410 {
411 	/* Those two values allow us to delay self-refresh activation
412 	 * to the maximum. */
413 	u32 lpr0, lpr1 = 0;
414 	u32 mdr, saved_mdr0, saved_mdr1 = 0;
415 	u32 saved_lpr0, saved_lpr1 = 0;
416 
417 	/* LPDDR1 --> force DDR2 mode during self-refresh */
418 	saved_mdr0 = at91_ramc_read(0, AT91_DDRSDRC_MDR);
419 	if ((saved_mdr0 & AT91_DDRSDRC_MD) == AT91_DDRSDRC_MD_LOW_POWER_DDR) {
420 		mdr = saved_mdr0 & ~AT91_DDRSDRC_MD;
421 		mdr |= AT91_DDRSDRC_MD_DDR2;
422 		at91_ramc_write(0, AT91_DDRSDRC_MDR, mdr);
423 	}
424 
425 	if (soc_pm.data.ramc[1]) {
426 		saved_lpr1 = at91_ramc_read(1, AT91_DDRSDRC_LPR);
427 		lpr1 = saved_lpr1 & ~AT91_DDRSDRC_LPCB;
428 		lpr1 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
429 		saved_mdr1 = at91_ramc_read(1, AT91_DDRSDRC_MDR);
430 		if ((saved_mdr1 & AT91_DDRSDRC_MD) == AT91_DDRSDRC_MD_LOW_POWER_DDR) {
431 			mdr = saved_mdr1 & ~AT91_DDRSDRC_MD;
432 			mdr |= AT91_DDRSDRC_MD_DDR2;
433 			at91_ramc_write(1, AT91_DDRSDRC_MDR, mdr);
434 		}
435 	}
436 
437 	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
438 	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
439 	lpr0 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
440 
441 	/* self-refresh mode now */
442 	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
443 	if (soc_pm.data.ramc[1])
444 		at91_ramc_write(1, AT91_DDRSDRC_LPR, lpr1);
445 
446 	cpu_do_idle();
447 
448 	at91_ramc_write(0, AT91_DDRSDRC_MDR, saved_mdr0);
449 	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
450 	if (soc_pm.data.ramc[1]) {
451 		at91_ramc_write(0, AT91_DDRSDRC_MDR, saved_mdr1);
452 		at91_ramc_write(1, AT91_DDRSDRC_LPR, saved_lpr1);
453 	}
454 }
455 
456 static void sama5d3_ddr_standby(void)
457 {
458 	u32 lpr0;
459 	u32 saved_lpr0;
460 
461 	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
462 	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
463 	lpr0 |= AT91_DDRSDRC_LPCB_POWER_DOWN;
464 
465 	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
466 
467 	cpu_do_idle();
468 
469 	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
470 }
471 
472 /* We manage both DDRAM/SDRAM controllers, we need more than one value to
473  * remember.
474  */
475 static void at91sam9_sdram_standby(void)
476 {
477 	u32 lpr0, lpr1 = 0;
478 	u32 saved_lpr0, saved_lpr1 = 0;
479 
480 	if (soc_pm.data.ramc[1]) {
481 		saved_lpr1 = at91_ramc_read(1, AT91_SDRAMC_LPR);
482 		lpr1 = saved_lpr1 & ~AT91_SDRAMC_LPCB;
483 		lpr1 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
484 	}
485 
486 	saved_lpr0 = at91_ramc_read(0, AT91_SDRAMC_LPR);
487 	lpr0 = saved_lpr0 & ~AT91_SDRAMC_LPCB;
488 	lpr0 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
489 
490 	/* self-refresh mode now */
491 	at91_ramc_write(0, AT91_SDRAMC_LPR, lpr0);
492 	if (soc_pm.data.ramc[1])
493 		at91_ramc_write(1, AT91_SDRAMC_LPR, lpr1);
494 
495 	cpu_do_idle();
496 
497 	at91_ramc_write(0, AT91_SDRAMC_LPR, saved_lpr0);
498 	if (soc_pm.data.ramc[1])
499 		at91_ramc_write(1, AT91_SDRAMC_LPR, saved_lpr1);
500 }
501 
502 struct ramc_info {
503 	void (*idle)(void);
504 	unsigned int memctrl;
505 };
506 
507 static const struct ramc_info ramc_infos[] __initconst = {
508 	{ .idle = at91rm9200_standby, .memctrl = AT91_MEMCTRL_MC},
509 	{ .idle = at91sam9_sdram_standby, .memctrl = AT91_MEMCTRL_SDRAMC},
510 	{ .idle = at91_ddr_standby, .memctrl = AT91_MEMCTRL_DDRSDR},
511 	{ .idle = sama5d3_ddr_standby, .memctrl = AT91_MEMCTRL_DDRSDR},
512 };
513 
514 static const struct of_device_id ramc_ids[] __initconst = {
515 	{ .compatible = "atmel,at91rm9200-sdramc", .data = &ramc_infos[0] },
516 	{ .compatible = "atmel,at91sam9260-sdramc", .data = &ramc_infos[1] },
517 	{ .compatible = "atmel,at91sam9g45-ddramc", .data = &ramc_infos[2] },
518 	{ .compatible = "atmel,sama5d3-ddramc", .data = &ramc_infos[3] },
519 	{ /*sentinel*/ }
520 };
521 
522 static __init void at91_dt_ramc(void)
523 {
524 	struct device_node *np;
525 	const struct of_device_id *of_id;
526 	int idx = 0;
527 	void *standby = NULL;
528 	const struct ramc_info *ramc;
529 
530 	for_each_matching_node_and_match(np, ramc_ids, &of_id) {
531 		soc_pm.data.ramc[idx] = of_iomap(np, 0);
532 		if (!soc_pm.data.ramc[idx])
533 			panic(pr_fmt("unable to map ramc[%d] cpu registers\n"), idx);
534 
535 		ramc = of_id->data;
536 		if (!standby)
537 			standby = ramc->idle;
538 		soc_pm.data.memctrl = ramc->memctrl;
539 
540 		idx++;
541 	}
542 
543 	if (!idx)
544 		panic(pr_fmt("unable to find compatible ram controller node in dtb\n"));
545 
546 	if (!standby) {
547 		pr_warn("ramc no standby function available\n");
548 		return;
549 	}
550 
551 	at91_cpuidle_device.dev.platform_data = standby;
552 }
553 
554 static void at91rm9200_idle(void)
555 {
556 	/*
557 	 * Disable the processor clock.  The processor will be automatically
558 	 * re-enabled by an interrupt or by a reset.
559 	 */
560 	writel(AT91_PMC_PCK, soc_pm.data.pmc + AT91_PMC_SCDR);
561 }
562 
563 static void at91sam9x60_idle(void)
564 {
565 	cpu_do_idle();
566 }
567 
568 static void at91sam9_idle(void)
569 {
570 	writel(AT91_PMC_PCK, soc_pm.data.pmc + AT91_PMC_SCDR);
571 	cpu_do_idle();
572 }
573 
574 static void __init at91_pm_sram_init(void)
575 {
576 	struct gen_pool *sram_pool;
577 	phys_addr_t sram_pbase;
578 	unsigned long sram_base;
579 	struct device_node *node;
580 	struct platform_device *pdev = NULL;
581 
582 	for_each_compatible_node(node, NULL, "mmio-sram") {
583 		pdev = of_find_device_by_node(node);
584 		if (pdev) {
585 			of_node_put(node);
586 			break;
587 		}
588 	}
589 
590 	if (!pdev) {
591 		pr_warn("%s: failed to find sram device!\n", __func__);
592 		return;
593 	}
594 
595 	sram_pool = gen_pool_get(&pdev->dev, NULL);
596 	if (!sram_pool) {
597 		pr_warn("%s: sram pool unavailable!\n", __func__);
598 		return;
599 	}
600 
601 	sram_base = gen_pool_alloc(sram_pool, at91_pm_suspend_in_sram_sz);
602 	if (!sram_base) {
603 		pr_warn("%s: unable to alloc sram!\n", __func__);
604 		return;
605 	}
606 
607 	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
608 	at91_suspend_sram_fn = __arm_ioremap_exec(sram_pbase,
609 					at91_pm_suspend_in_sram_sz, false);
610 	if (!at91_suspend_sram_fn) {
611 		pr_warn("SRAM: Could not map\n");
612 		return;
613 	}
614 
615 	/* Copy the pm suspend handler to SRAM */
616 	at91_suspend_sram_fn = fncpy(at91_suspend_sram_fn,
617 			&at91_pm_suspend_in_sram, at91_pm_suspend_in_sram_sz);
618 }
619 
620 static bool __init at91_is_pm_mode_active(int pm_mode)
621 {
622 	return (soc_pm.data.standby_mode == pm_mode ||
623 		soc_pm.data.suspend_mode == pm_mode);
624 }
625 
626 static int __init at91_pm_backup_init(void)
627 {
628 	struct gen_pool *sram_pool;
629 	struct device_node *np;
630 	struct platform_device *pdev = NULL;
631 	int ret = -ENODEV;
632 
633 	if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
634 		return -EPERM;
635 
636 	if (!at91_is_pm_mode_active(AT91_PM_BACKUP))
637 		return 0;
638 
639 	np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-sfrbu");
640 	if (!np) {
641 		pr_warn("%s: failed to find sfrbu!\n", __func__);
642 		return ret;
643 	}
644 
645 	soc_pm.data.sfrbu = of_iomap(np, 0);
646 	of_node_put(np);
647 
648 	np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-securam");
649 	if (!np)
650 		goto securam_fail_no_ref_dev;
651 
652 	pdev = of_find_device_by_node(np);
653 	of_node_put(np);
654 	if (!pdev) {
655 		pr_warn("%s: failed to find securam device!\n", __func__);
656 		goto securam_fail_no_ref_dev;
657 	}
658 
659 	sram_pool = gen_pool_get(&pdev->dev, NULL);
660 	if (!sram_pool) {
661 		pr_warn("%s: securam pool unavailable!\n", __func__);
662 		goto securam_fail;
663 	}
664 
665 	pm_bu = (void *)gen_pool_alloc(sram_pool, sizeof(struct at91_pm_bu));
666 	if (!pm_bu) {
667 		pr_warn("%s: unable to alloc securam!\n", __func__);
668 		ret = -ENOMEM;
669 		goto securam_fail;
670 	}
671 
672 	pm_bu->suspended = 0;
673 	pm_bu->canary = __pa_symbol(&canary);
674 	pm_bu->resume = __pa_symbol(cpu_resume);
675 
676 	return 0;
677 
678 securam_fail:
679 	put_device(&pdev->dev);
680 securam_fail_no_ref_dev:
681 	iounmap(soc_pm.data.sfrbu);
682 	soc_pm.data.sfrbu = NULL;
683 	return ret;
684 }
685 
686 static void __init at91_pm_use_default_mode(int pm_mode)
687 {
688 	if (pm_mode != AT91_PM_ULP1 && pm_mode != AT91_PM_BACKUP)
689 		return;
690 
691 	if (soc_pm.data.standby_mode == pm_mode)
692 		soc_pm.data.standby_mode = AT91_PM_ULP0;
693 	if (soc_pm.data.suspend_mode == pm_mode)
694 		soc_pm.data.suspend_mode = AT91_PM_ULP0;
695 }
696 
697 static void __init at91_pm_modes_init(void)
698 {
699 	struct device_node *np;
700 	int ret;
701 
702 	if (!at91_is_pm_mode_active(AT91_PM_BACKUP) &&
703 	    !at91_is_pm_mode_active(AT91_PM_ULP1))
704 		return;
705 
706 	np = of_find_compatible_node(NULL, NULL, "atmel,sama5d2-shdwc");
707 	if (!np) {
708 		pr_warn("%s: failed to find shdwc!\n", __func__);
709 		goto ulp1_default;
710 	}
711 
712 	soc_pm.data.shdwc = of_iomap(np, 0);
713 	of_node_put(np);
714 
715 	ret = at91_pm_backup_init();
716 	if (ret) {
717 		if (!at91_is_pm_mode_active(AT91_PM_ULP1))
718 			goto unmap;
719 		else
720 			goto backup_default;
721 	}
722 
723 	return;
724 
725 unmap:
726 	iounmap(soc_pm.data.shdwc);
727 	soc_pm.data.shdwc = NULL;
728 ulp1_default:
729 	at91_pm_use_default_mode(AT91_PM_ULP1);
730 backup_default:
731 	at91_pm_use_default_mode(AT91_PM_BACKUP);
732 }
733 
734 struct pmc_info {
735 	unsigned long uhp_udp_mask;
736 };
737 
738 static const struct pmc_info pmc_infos[] __initconst = {
739 	{ .uhp_udp_mask = AT91RM9200_PMC_UHP | AT91RM9200_PMC_UDP },
740 	{ .uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP },
741 	{ .uhp_udp_mask = AT91SAM926x_PMC_UHP },
742 	{ .uhp_udp_mask = 0 },
743 };
744 
745 static const struct of_device_id atmel_pmc_ids[] __initconst = {
746 	{ .compatible = "atmel,at91rm9200-pmc", .data = &pmc_infos[0] },
747 	{ .compatible = "atmel,at91sam9260-pmc", .data = &pmc_infos[1] },
748 	{ .compatible = "atmel,at91sam9261-pmc", .data = &pmc_infos[1] },
749 	{ .compatible = "atmel,at91sam9263-pmc", .data = &pmc_infos[1] },
750 	{ .compatible = "atmel,at91sam9g45-pmc", .data = &pmc_infos[2] },
751 	{ .compatible = "atmel,at91sam9n12-pmc", .data = &pmc_infos[1] },
752 	{ .compatible = "atmel,at91sam9rl-pmc", .data = &pmc_infos[3] },
753 	{ .compatible = "atmel,at91sam9x5-pmc", .data = &pmc_infos[1] },
754 	{ .compatible = "atmel,sama5d3-pmc", .data = &pmc_infos[1] },
755 	{ .compatible = "atmel,sama5d4-pmc", .data = &pmc_infos[1] },
756 	{ .compatible = "atmel,sama5d2-pmc", .data = &pmc_infos[1] },
757 	{ /* sentinel */ },
758 };
759 
760 static void __init at91_pm_init(void (*pm_idle)(void))
761 {
762 	struct device_node *pmc_np;
763 	const struct of_device_id *of_id;
764 	const struct pmc_info *pmc;
765 
766 	if (at91_cpuidle_device.dev.platform_data)
767 		platform_device_register(&at91_cpuidle_device);
768 
769 	pmc_np = of_find_matching_node_and_match(NULL, atmel_pmc_ids, &of_id);
770 	soc_pm.data.pmc = of_iomap(pmc_np, 0);
771 	if (!soc_pm.data.pmc) {
772 		pr_err("AT91: PM not supported, PMC not found\n");
773 		return;
774 	}
775 
776 	pmc = of_id->data;
777 	soc_pm.data.uhp_udp_mask = pmc->uhp_udp_mask;
778 
779 	if (pm_idle)
780 		arm_pm_idle = pm_idle;
781 
782 	at91_pm_sram_init();
783 
784 	if (at91_suspend_sram_fn) {
785 		suspend_set_ops(&at91_pm_ops);
786 		pr_info("AT91: PM: standby: %s, suspend: %s\n",
787 			pm_modes[soc_pm.data.standby_mode].pattern,
788 			pm_modes[soc_pm.data.suspend_mode].pattern);
789 	} else {
790 		pr_info("AT91: PM not supported, due to no SRAM allocated\n");
791 	}
792 }
793 
794 void __init at91rm9200_pm_init(void)
795 {
796 	if (!IS_ENABLED(CONFIG_SOC_AT91RM9200))
797 		return;
798 
799 	at91_dt_ramc();
800 
801 	/*
802 	 * AT91RM9200 SDRAM low-power mode cannot be used with self-refresh.
803 	 */
804 	at91_ramc_write(0, AT91_MC_SDRAMC_LPR, 0);
805 
806 	at91_pm_init(at91rm9200_idle);
807 }
808 
809 void __init sam9x60_pm_init(void)
810 {
811 	if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
812 		return;
813 
814 	at91_pm_modes_init();
815 	at91_dt_ramc();
816 	at91_pm_init(at91sam9x60_idle);
817 
818 	soc_pm.ws_ids = sam9x60_ws_ids;
819 	soc_pm.config_pmc_ws = at91_sam9x60_config_pmc_ws;
820 }
821 
822 void __init at91sam9_pm_init(void)
823 {
824 	if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
825 		return;
826 
827 	at91_dt_ramc();
828 	at91_pm_init(at91sam9_idle);
829 }
830 
831 void __init sama5_pm_init(void)
832 {
833 	if (!IS_ENABLED(CONFIG_SOC_SAMA5))
834 		return;
835 
836 	at91_dt_ramc();
837 	at91_pm_init(NULL);
838 }
839 
840 void __init sama5d2_pm_init(void)
841 {
842 	if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
843 		return;
844 
845 	at91_pm_modes_init();
846 	sama5_pm_init();
847 
848 	soc_pm.ws_ids = sama5d2_ws_ids;
849 	soc_pm.config_shdwc_ws = at91_sama5d2_config_shdwc_ws;
850 	soc_pm.config_pmc_ws = at91_sama5d2_config_pmc_ws;
851 }
852 
853 static int __init at91_pm_modes_select(char *str)
854 {
855 	char *s;
856 	substring_t args[MAX_OPT_ARGS];
857 	int standby, suspend;
858 
859 	if (!str)
860 		return 0;
861 
862 	s = strsep(&str, ",");
863 	standby = match_token(s, pm_modes, args);
864 	if (standby < 0)
865 		return 0;
866 
867 	suspend = match_token(str, pm_modes, args);
868 	if (suspend < 0)
869 		return 0;
870 
871 	soc_pm.data.standby_mode = standby;
872 	soc_pm.data.suspend_mode = suspend;
873 
874 	return 0;
875 }
876 early_param("atmel.pm_modes", at91_pm_modes_select);
877