Linux Audio

Check our new training course

Loading...
v3.5.6
  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/gpio.h>
 14#include <linux/suspend.h>
 15#include <linux/sched.h>
 16#include <linux/proc_fs.h>
 
 17#include <linux/interrupt.h>
 18#include <linux/sysfs.h>
 19#include <linux/module.h>
 
 
 
 20#include <linux/platform_device.h>
 
 21#include <linux/io.h>
 
 22
 23#include <asm/irq.h>
 24#include <linux/atomic.h>
 25#include <asm/mach/time.h>
 26#include <asm/mach/irq.h>
 27
 28#include <mach/at91_pmc.h>
 29#include <mach/cpu.h>
 30
 31#include "generic.h"
 32#include "pm.h"
 33
 
 
 34/*
 35 * Show the reason for the previous system reset.
 
 
 
 36 */
 
 
 
 
 37
 38#include <mach/at91_rstc.h>
 39#include <mach/at91_shdwc.h>
 40
 41static void __init show_reset_status(void)
 42{
 43	static char reset[] __initdata = "reset";
 44
 45	static char general[] __initdata = "general";
 46	static char wakeup[] __initdata = "wakeup";
 47	static char watchdog[] __initdata = "watchdog";
 48	static char software[] __initdata = "software";
 49	static char user[] __initdata = "user";
 50	static char unknown[] __initdata = "unknown";
 51
 52	static char signal[] __initdata = "signal";
 53	static char rtc[] __initdata = "rtc";
 54	static char rtt[] __initdata = "rtt";
 55	static char restore[] __initdata = "power-restored";
 56
 57	char *reason, *r2 = reset;
 58	u32 reset_type, wake_type;
 59
 60	if (!at91_shdwc_base || !at91_rstc_base)
 61		return;
 62
 63	reset_type = at91_rstc_read(AT91_RSTC_SR) & AT91_RSTC_RSTTYP;
 64	wake_type = at91_shdwc_read(AT91_SHDW_SR);
 65
 66	switch (reset_type) {
 67	case AT91_RSTC_RSTTYP_GENERAL:
 68		reason = general;
 69		break;
 70	case AT91_RSTC_RSTTYP_WAKEUP:
 71		/* board-specific code enabled the wakeup sources */
 72		reason = wakeup;
 73
 74		/* "wakeup signal" */
 75		if (wake_type & AT91_SHDW_WAKEUP0)
 76			r2 = signal;
 77		else {
 78			r2 = reason;
 79			if (wake_type & AT91_SHDW_RTTWK)	/* rtt wakeup */
 80				reason = rtt;
 81			else if (wake_type & AT91_SHDW_RTCWK)	/* rtc wakeup */
 82				reason = rtc;
 83			else if (wake_type == 0)	/* power-restored wakeup */
 84				reason = restore;
 85			else				/* unknown wakeup */
 86				reason = unknown;
 87		}
 88		break;
 89	case AT91_RSTC_RSTTYP_WATCHDOG:
 90		reason = watchdog;
 91		break;
 92	case AT91_RSTC_RSTTYP_SOFTWARE:
 93		reason = software;
 94		break;
 95	case AT91_RSTC_RSTTYP_USER:
 96		reason = user;
 97		break;
 98	default:
 99		reason = unknown;
100		break;
101	}
102	pr_info("AT91: Starting after %s %s\n", reason, r2);
103}
104
105static int at91_pm_valid_state(suspend_state_t state)
106{
107	switch (state) {
108		case PM_SUSPEND_ON:
109		case PM_SUSPEND_STANDBY:
110		case PM_SUSPEND_MEM:
111			return 1;
112
113		default:
114			return 0;
115	}
116}
117
118
119static suspend_state_t target_state;
120
121/*
122 * Called after processes are frozen, but before we shutdown devices.
123 */
124static int at91_pm_begin(suspend_state_t state)
125{
126	target_state = state;
127	return 0;
128}
129
130/*
131 * Verify that all the clocks are correct before entering
132 * slow-clock mode.
133 */
134static int at91_pm_verify_clocks(void)
135{
136	unsigned long scsr;
137	int i;
138
139	scsr = at91_pmc_read(AT91_PMC_SCSR);
140
141	/* USB must not be using PLLB */
142	if (cpu_is_at91rm9200()) {
143		if ((scsr & (AT91RM9200_PMC_UHP | AT91RM9200_PMC_UDP)) != 0) {
144			pr_err("AT91: PM - Suspend-to-RAM with USB still active\n");
145			return 0;
146		}
147	} else if (cpu_is_at91sam9260() || cpu_is_at91sam9261() || cpu_is_at91sam9263()
148			|| cpu_is_at91sam9g20() || cpu_is_at91sam9g10()) {
149		if ((scsr & (AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP)) != 0) {
150			pr_err("AT91: PM - Suspend-to-RAM with USB still active\n");
151			return 0;
152		}
153	}
154
155#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS
156	/* PCK0..PCK3 must be disabled, or configured to use clk32k */
157	for (i = 0; i < 4; i++) {
158		u32 css;
159
160		if ((scsr & (AT91_PMC_PCK0 << i)) == 0)
161			continue;
162
163		css = at91_pmc_read(AT91_PMC_PCKR(i)) & AT91_PMC_CSS;
164		if (css != AT91_PMC_CSS_SLOW) {
165			pr_err("AT91: PM - Suspend-to-RAM with PCK%d src %d\n", i, css);
166			return 0;
167		}
168	}
169#endif
170
171	return 1;
172}
173
174/*
175 * Call this from platform driver suspend() to see how deeply to suspend.
176 * For example, some controllers (like OHCI) need one of the PLL clocks
177 * in order to act as a wakeup source, and those are not available when
178 * going into slow clock mode.
179 *
180 * REVISIT: generalize as clk_will_be_available(clk)?  Other platforms have
181 * the very same problem (but not using at91 main_clk), and it'd be better
182 * to add one generic API rather than lots of platform-specific ones.
183 */
184int at91_suspend_entering_slow_clock(void)
185{
186	return (target_state == PM_SUSPEND_MEM);
187}
188EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
189
190
191static void (*slow_clock)(void __iomem *pmc, void __iomem *ramc0,
192			  void __iomem *ramc1, int memctrl);
193
194#ifdef CONFIG_AT91_SLOW_CLOCK
195extern void at91_slow_clock(void __iomem *pmc, void __iomem *ramc0,
196			    void __iomem *ramc1, int memctrl);
197extern u32 at91_slow_clock_sz;
198#endif
199
200static int at91_pm_enter(suspend_state_t state)
201{
202	at91_gpio_suspend();
203	at91_irq_suspend();
 
 
 
 
 
204
205	pr_debug("AT91: PM - wake mask %08x, pm state %d\n",
206			/* remember all the always-wake irqs */
207			(at91_pmc_read(AT91_PMC_PCSR)
208					| (1 << AT91_ID_FIQ)
209					| (1 << AT91_ID_SYS)
210					| (at91_extern_irq))
211				& at91_aic_read(AT91_AIC_IMR),
212			state);
213
 
 
 
 
 
214	switch (state) {
 
 
 
 
 
 
215		/*
216		 * Suspend-to-RAM is like STANDBY plus slow clock mode, so
217		 * drivers must suspend more deeply:  only the master clock
218		 * controller may be using the main oscillator.
219		 */
220		case PM_SUSPEND_MEM:
221			/*
222			 * Ensure that clocks are in a valid state.
223			 */
224			if (!at91_pm_verify_clocks())
225				goto error;
226
227			/*
228			 * Enter slow clock mode by switching over to clk32k and
229			 * turning off the main oscillator; reverse on wakeup.
230			 */
231			if (slow_clock) {
232				int memctrl = AT91_MEMCTRL_SDRAMC;
233
234				if (cpu_is_at91rm9200())
235					memctrl = AT91_MEMCTRL_MC;
236				else if (cpu_is_at91sam9g45())
237					memctrl = AT91_MEMCTRL_DDRSDR;
238#ifdef CONFIG_AT91_SLOW_CLOCK
239				/* copy slow_clock handler to SRAM, and call it */
240				memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);
241#endif
242				slow_clock(at91_pmc_base, at91_ramc_base[0],
243					   at91_ramc_base[1], memctrl);
244				break;
245			} else {
246				pr_info("AT91: PM - no slow clock mode enabled ...\n");
247				/* FALLTHROUGH leaving master clock alone */
248			}
249
250		/*
251		 * STANDBY mode has *all* drivers suspended; ignores irqs not
252		 * marked as 'wakeup' event sources; and reduces DRAM power.
253		 * But otherwise it's identical to PM_SUSPEND_ON:  cpu idle, and
254		 * nothing fancy done with main or cpu clocks.
255		 */
256		case PM_SUSPEND_STANDBY:
257			/*
258			 * NOTE: the Wait-for-Interrupt instruction needs to be
259			 * in icache so no SDRAM accesses are needed until the
260			 * wakeup IRQ occurs and self-refresh is terminated.
261			 * For ARM 926 based chips, this requirement is weaker
262			 * as at91sam9 can access a RAM in self-refresh mode.
263			 */
264			if (cpu_is_at91rm9200())
265				at91rm9200_standby();
266			else if (cpu_is_at91sam9g45())
267				at91sam9g45_standby();
268			else
269				at91sam9_standby();
270			break;
271
272		case PM_SUSPEND_ON:
273			cpu_do_idle();
274			break;
275
276		default:
277			pr_debug("AT91: PM - bogus suspend state %d\n", state);
278			goto error;
279	}
 
 
 
 
 
280
281	pr_debug("AT91: PM - wakeup %08x\n",
282			at91_aic_read(AT91_AIC_IPR) & at91_aic_read(AT91_AIC_IMR));
 
 
 
 
 
 
283
284error:
285	target_state = PM_SUSPEND_ON;
286	at91_irq_resume();
287	at91_gpio_resume();
 
 
288	return 0;
289}
290
291/*
292 * Called right prior to thawing processes.
293 */
294static void at91_pm_end(void)
295{
296	target_state = PM_SUSPEND_ON;
297}
298
299
300static const struct platform_suspend_ops at91_pm_ops = {
301	.valid	= at91_pm_valid_state,
302	.begin	= at91_pm_begin,
303	.enter	= at91_pm_enter,
304	.end	= at91_pm_end,
305};
306
307static int __init at91_pm_init(void)
 
 
 
 
308{
309#ifdef CONFIG_AT91_SLOW_CLOCK
310	slow_clock = (void *) (AT91_IO_VIRT_BASE - at91_slow_clock_sz);
311#endif
312
313	pr_info("AT91: Power Management%s\n", (slow_clock ? " (with slow clock mode)" : ""));
 
 
 
 
 
 
 
 
 
 
 
314
315	/* AT91RM9200 SDRAM low-power mode cannot be used with self-refresh. */
316	if (cpu_is_at91rm9200())
317		at91_ramc_write(0, AT91RM9200_SDRAMC_LPR, 0);
 
 
 
 
 
 
 
 
 
 
318
319	suspend_set_ops(&at91_pm_ops);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
320
321	show_reset_status();
322	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
323}
324arch_initcall(at91_pm_init);
v4.10.11
  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/gpio.h>
 14#include <linux/suspend.h>
 15#include <linux/sched.h>
 16#include <linux/proc_fs.h>
 17#include <linux/genalloc.h>
 18#include <linux/interrupt.h>
 19#include <linux/sysfs.h>
 20#include <linux/module.h>
 21#include <linux/of.h>
 22#include <linux/of_platform.h>
 23#include <linux/of_address.h>
 24#include <linux/platform_device.h>
 25#include <linux/platform_data/atmel.h>
 26#include <linux/io.h>
 27#include <linux/clk/at91_pmc.h>
 28
 29#include <asm/irq.h>
 30#include <linux/atomic.h>
 31#include <asm/mach/time.h>
 32#include <asm/mach/irq.h>
 33#include <asm/fncpy.h>
 34#include <asm/cacheflush.h>
 35#include <asm/system_misc.h>
 36
 37#include "generic.h"
 38#include "pm.h"
 39
 40static void __iomem *pmc;
 41
 42/*
 43 * FIXME: this is needed to communicate between the pinctrl driver and
 44 * the PM implementation in the machine. Possibly part of the PM
 45 * implementation should be moved down into the pinctrl driver and get
 46 * called as part of the generic suspend/resume path.
 47 */
 48#ifdef CONFIG_PINCTRL_AT91
 49extern void at91_pinctrl_gpio_suspend(void);
 50extern void at91_pinctrl_gpio_resume(void);
 51#endif
 52
 53static struct {
 54	unsigned long uhp_udp_mask;
 55	int memctrl;
 56} at91_pm_data;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 57
 58void __iomem *at91_ramc_base[2];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 59
 60static int at91_pm_valid_state(suspend_state_t state)
 61{
 62	switch (state) {
 63		case PM_SUSPEND_ON:
 64		case PM_SUSPEND_STANDBY:
 65		case PM_SUSPEND_MEM:
 66			return 1;
 67
 68		default:
 69			return 0;
 70	}
 71}
 72
 73
 74static suspend_state_t target_state;
 75
 76/*
 77 * Called after processes are frozen, but before we shutdown devices.
 78 */
 79static int at91_pm_begin(suspend_state_t state)
 80{
 81	target_state = state;
 82	return 0;
 83}
 84
 85/*
 86 * Verify that all the clocks are correct before entering
 87 * slow-clock mode.
 88 */
 89static int at91_pm_verify_clocks(void)
 90{
 91	unsigned long scsr;
 92	int i;
 93
 94	scsr = readl(pmc + AT91_PMC_SCSR);
 95
 96	/* USB must not be using PLLB */
 97	if ((scsr & at91_pm_data.uhp_udp_mask) != 0) {
 98		pr_err("AT91: PM - Suspend-to-RAM with USB still active\n");
 99		return 0;
 
 
 
 
 
 
 
 
100	}
101
 
102	/* PCK0..PCK3 must be disabled, or configured to use clk32k */
103	for (i = 0; i < 4; i++) {
104		u32 css;
105
106		if ((scsr & (AT91_PMC_PCK0 << i)) == 0)
107			continue;
108		css = readl(pmc + AT91_PMC_PCKR(i)) & AT91_PMC_CSS;
 
109		if (css != AT91_PMC_CSS_SLOW) {
110			pr_err("AT91: PM - Suspend-to-RAM with PCK%d src %d\n", i, css);
111			return 0;
112		}
113	}
 
114
115	return 1;
116}
117
118/*
119 * Call this from platform driver suspend() to see how deeply to suspend.
120 * For example, some controllers (like OHCI) need one of the PLL clocks
121 * in order to act as a wakeup source, and those are not available when
122 * going into slow clock mode.
123 *
124 * REVISIT: generalize as clk_will_be_available(clk)?  Other platforms have
125 * the very same problem (but not using at91 main_clk), and it'd be better
126 * to add one generic API rather than lots of platform-specific ones.
127 */
128int at91_suspend_entering_slow_clock(void)
129{
130	return (target_state == PM_SUSPEND_MEM);
131}
132EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
133
134static void (*at91_suspend_sram_fn)(void __iomem *pmc, void __iomem *ramc0,
 
135			  void __iomem *ramc1, int memctrl);
136
137extern void at91_pm_suspend_in_sram(void __iomem *pmc, void __iomem *ramc0,
 
138			    void __iomem *ramc1, int memctrl);
139extern u32 at91_pm_suspend_in_sram_sz;
 
140
141static void at91_pm_suspend(suspend_state_t state)
142{
143	unsigned int pm_data = at91_pm_data.memctrl;
144
145	pm_data |= (state == PM_SUSPEND_MEM) ?
146				AT91_PM_MODE(AT91_PM_SLOW_CLOCK) : 0;
147
148	flush_cache_all();
149	outer_disable();
150
151	at91_suspend_sram_fn(pmc, at91_ramc_base[0],
152			     at91_ramc_base[1], pm_data);
153
154	outer_resume();
155}
 
 
 
156
157static int at91_pm_enter(suspend_state_t state)
158{
159#ifdef CONFIG_PINCTRL_AT91
160	at91_pinctrl_gpio_suspend();
161#endif
162	switch (state) {
163	/*
164	 * Suspend-to-RAM is like STANDBY plus slow clock mode, so
165	 * drivers must suspend more deeply, the master clock switches
166	 * to the clk32k and turns off the main oscillator
167	 */
168	case PM_SUSPEND_MEM:
169		/*
170		 * Ensure that clocks are in a valid state.
 
 
171		 */
172		if (!at91_pm_verify_clocks())
173			goto error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
174
175		at91_pm_suspend(state);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
176
177		break;
 
 
178
179	/*
180	 * STANDBY mode has *all* drivers suspended; ignores irqs not
181	 * marked as 'wakeup' event sources; and reduces DRAM power.
182	 * But otherwise it's identical to PM_SUSPEND_ON: cpu idle, and
183	 * nothing fancy done with main or cpu clocks.
184	 */
185	case PM_SUSPEND_STANDBY:
186		at91_pm_suspend(state);
187		break;
188
189	case PM_SUSPEND_ON:
190		cpu_do_idle();
191		break;
192
193	default:
194		pr_debug("AT91: PM - bogus suspend state %d\n", state);
195		goto error;
196	}
197
198error:
199	target_state = PM_SUSPEND_ON;
200
201#ifdef CONFIG_PINCTRL_AT91
202	at91_pinctrl_gpio_resume();
203#endif
204	return 0;
205}
206
207/*
208 * Called right prior to thawing processes.
209 */
210static void at91_pm_end(void)
211{
212	target_state = PM_SUSPEND_ON;
213}
214
215
216static const struct platform_suspend_ops at91_pm_ops = {
217	.valid	= at91_pm_valid_state,
218	.begin	= at91_pm_begin,
219	.enter	= at91_pm_enter,
220	.end	= at91_pm_end,
221};
222
223static struct platform_device at91_cpuidle_device = {
224	.name = "cpuidle-at91",
225};
226
227static void at91_pm_set_standby(void (*at91_standby)(void))
228{
229	if (at91_standby)
230		at91_cpuidle_device.dev.platform_data = at91_standby;
231}
232
233/*
234 * The AT91RM9200 goes into self-refresh mode with this command, and will
235 * terminate self-refresh automatically on the next SDRAM access.
236 *
237 * Self-refresh mode is exited as soon as a memory access is made, but we don't
238 * know for sure when that happens. However, we need to restore the low-power
239 * mode if it was enabled before going idle. Restoring low-power mode while
240 * still in self-refresh is "not recommended", but seems to work.
241 */
242static void at91rm9200_standby(void)
243{
244	u32 lpr = at91_ramc_read(0, AT91_MC_SDRAMC_LPR);
245
246	asm volatile(
247		"b    1f\n\t"
248		".align    5\n\t"
249		"1:  mcr    p15, 0, %0, c7, c10, 4\n\t"
250		"    str    %0, [%1, %2]\n\t"
251		"    str    %3, [%1, %4]\n\t"
252		"    mcr    p15, 0, %0, c7, c0, 4\n\t"
253		"    str    %5, [%1, %2]"
254		:
255		: "r" (0), "r" (at91_ramc_base[0]), "r" (AT91_MC_SDRAMC_LPR),
256		  "r" (1), "r" (AT91_MC_SDRAMC_SRR),
257		  "r" (lpr));
258}
259
260/* We manage both DDRAM/SDRAM controllers, we need more than one value to
261 * remember.
262 */
263static void at91_ddr_standby(void)
264{
265	/* Those two values allow us to delay self-refresh activation
266	 * to the maximum. */
267	u32 lpr0, lpr1 = 0;
268	u32 saved_lpr0, saved_lpr1 = 0;
269
270	if (at91_ramc_base[1]) {
271		saved_lpr1 = at91_ramc_read(1, AT91_DDRSDRC_LPR);
272		lpr1 = saved_lpr1 & ~AT91_DDRSDRC_LPCB;
273		lpr1 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
274	}
275
276	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
277	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
278	lpr0 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
279
280	/* self-refresh mode now */
281	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
282	if (at91_ramc_base[1])
283		at91_ramc_write(1, AT91_DDRSDRC_LPR, lpr1);
284
285	cpu_do_idle();
286
287	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
288	if (at91_ramc_base[1])
289		at91_ramc_write(1, AT91_DDRSDRC_LPR, saved_lpr1);
290}
291
292static void sama5d3_ddr_standby(void)
293{
294	u32 lpr0;
295	u32 saved_lpr0;
296
297	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
298	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
299	lpr0 |= AT91_DDRSDRC_LPCB_POWER_DOWN;
300
301	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
302
303	cpu_do_idle();
304
305	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
306}
307
308/* We manage both DDRAM/SDRAM controllers, we need more than one value to
309 * remember.
310 */
311static void at91sam9_sdram_standby(void)
312{
313	u32 lpr0, lpr1 = 0;
314	u32 saved_lpr0, saved_lpr1 = 0;
315
316	if (at91_ramc_base[1]) {
317		saved_lpr1 = at91_ramc_read(1, AT91_SDRAMC_LPR);
318		lpr1 = saved_lpr1 & ~AT91_SDRAMC_LPCB;
319		lpr1 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
320	}
321
322	saved_lpr0 = at91_ramc_read(0, AT91_SDRAMC_LPR);
323	lpr0 = saved_lpr0 & ~AT91_SDRAMC_LPCB;
324	lpr0 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
325
326	/* self-refresh mode now */
327	at91_ramc_write(0, AT91_SDRAMC_LPR, lpr0);
328	if (at91_ramc_base[1])
329		at91_ramc_write(1, AT91_SDRAMC_LPR, lpr1);
330
331	cpu_do_idle();
332
333	at91_ramc_write(0, AT91_SDRAMC_LPR, saved_lpr0);
334	if (at91_ramc_base[1])
335		at91_ramc_write(1, AT91_SDRAMC_LPR, saved_lpr1);
336}
337
338static const struct of_device_id const ramc_ids[] __initconst = {
339	{ .compatible = "atmel,at91rm9200-sdramc", .data = at91rm9200_standby },
340	{ .compatible = "atmel,at91sam9260-sdramc", .data = at91sam9_sdram_standby },
341	{ .compatible = "atmel,at91sam9g45-ddramc", .data = at91_ddr_standby },
342	{ .compatible = "atmel,sama5d3-ddramc", .data = sama5d3_ddr_standby },
343	{ /*sentinel*/ }
344};
345
346static __init void at91_dt_ramc(void)
347{
348	struct device_node *np;
349	const struct of_device_id *of_id;
350	int idx = 0;
351	const void *standby = NULL;
352
353	for_each_matching_node_and_match(np, ramc_ids, &of_id) {
354		at91_ramc_base[idx] = of_iomap(np, 0);
355		if (!at91_ramc_base[idx])
356			panic(pr_fmt("unable to map ramc[%d] cpu registers\n"), idx);
357
358		if (!standby)
359			standby = of_id->data;
360
361		idx++;
362	}
363
364	if (!idx)
365		panic(pr_fmt("unable to find compatible ram controller node in dtb\n"));
366
367	if (!standby) {
368		pr_warn("ramc no standby function available\n");
369		return;
370	}
371
372	at91_pm_set_standby(standby);
373}
374
375static void at91rm9200_idle(void)
376{
377	/*
378	 * Disable the processor clock.  The processor will be automatically
379	 * re-enabled by an interrupt or by a reset.
380	 */
381	writel(AT91_PMC_PCK, pmc + AT91_PMC_SCDR);
382}
383
384static void at91sam9_idle(void)
385{
386	writel(AT91_PMC_PCK, pmc + AT91_PMC_SCDR);
387	cpu_do_idle();
388}
389
390static void __init at91_pm_sram_init(void)
391{
392	struct gen_pool *sram_pool;
393	phys_addr_t sram_pbase;
394	unsigned long sram_base;
395	struct device_node *node;
396	struct platform_device *pdev = NULL;
397
398	for_each_compatible_node(node, NULL, "mmio-sram") {
399		pdev = of_find_device_by_node(node);
400		if (pdev) {
401			of_node_put(node);
402			break;
403		}
404	}
405
406	if (!pdev) {
407		pr_warn("%s: failed to find sram device!\n", __func__);
408		return;
409	}
410
411	sram_pool = gen_pool_get(&pdev->dev, NULL);
412	if (!sram_pool) {
413		pr_warn("%s: sram pool unavailable!\n", __func__);
414		return;
415	}
416
417	sram_base = gen_pool_alloc(sram_pool, at91_pm_suspend_in_sram_sz);
418	if (!sram_base) {
419		pr_warn("%s: unable to alloc sram!\n", __func__);
420		return;
421	}
422
423	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
424	at91_suspend_sram_fn = __arm_ioremap_exec(sram_pbase,
425					at91_pm_suspend_in_sram_sz, false);
426	if (!at91_suspend_sram_fn) {
427		pr_warn("SRAM: Could not map\n");
428		return;
429	}
430
431	/* Copy the pm suspend handler to SRAM */
432	at91_suspend_sram_fn = fncpy(at91_suspend_sram_fn,
433			&at91_pm_suspend_in_sram, at91_pm_suspend_in_sram_sz);
434}
435
436static const struct of_device_id atmel_pmc_ids[] __initconst = {
437	{ .compatible = "atmel,at91rm9200-pmc"  },
438	{ .compatible = "atmel,at91sam9260-pmc" },
439	{ .compatible = "atmel,at91sam9g45-pmc" },
440	{ .compatible = "atmel,at91sam9n12-pmc" },
441	{ .compatible = "atmel,at91sam9x5-pmc" },
442	{ .compatible = "atmel,sama5d3-pmc" },
443	{ .compatible = "atmel,sama5d2-pmc" },
444	{ /* sentinel */ },
445};
446
447static void __init at91_pm_init(void (*pm_idle)(void))
448{
449	struct device_node *pmc_np;
450
451	if (at91_cpuidle_device.dev.platform_data)
452		platform_device_register(&at91_cpuidle_device);
453
454	pmc_np = of_find_matching_node(NULL, atmel_pmc_ids);
455	pmc = of_iomap(pmc_np, 0);
456	if (!pmc) {
457		pr_err("AT91: PM not supported, PMC not found\n");
458		return;
459	}
460
461	if (pm_idle)
462		arm_pm_idle = pm_idle;
463
464	at91_pm_sram_init();
465
466	if (at91_suspend_sram_fn)
467		suspend_set_ops(&at91_pm_ops);
468	else
469		pr_info("AT91: PM not supported, due to no SRAM allocated\n");
470}
471
472void __init at91rm9200_pm_init(void)
473{
474	at91_dt_ramc();
475
476	/*
477	 * AT91RM9200 SDRAM low-power mode cannot be used with self-refresh.
478	 */
479	at91_ramc_write(0, AT91_MC_SDRAMC_LPR, 0);
480
481	at91_pm_data.uhp_udp_mask = AT91RM9200_PMC_UHP | AT91RM9200_PMC_UDP;
482	at91_pm_data.memctrl = AT91_MEMCTRL_MC;
483
484	at91_pm_init(at91rm9200_idle);
485}
486
487void __init at91sam9260_pm_init(void)
488{
489	at91_dt_ramc();
490	at91_pm_data.memctrl = AT91_MEMCTRL_SDRAMC;
491	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP;
492	at91_pm_init(at91sam9_idle);
493}
494
495void __init at91sam9g45_pm_init(void)
496{
497	at91_dt_ramc();
498	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP;
499	at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR;
500	at91_pm_init(at91sam9_idle);
501}
502
503void __init at91sam9x5_pm_init(void)
504{
505	at91_dt_ramc();
506	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP;
507	at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR;
508	at91_pm_init(at91sam9_idle);
509}
510
511void __init sama5_pm_init(void)
512{
513	at91_dt_ramc();
514	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP;
515	at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR;
516	at91_pm_init(NULL);
517}