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);
v4.6
  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/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/io.h>
 26#include <linux/clk/at91_pmc.h>
 27
 28#include <asm/irq.h>
 29#include <linux/atomic.h>
 30#include <asm/mach/time.h>
 31#include <asm/mach/irq.h>
 32#include <asm/fncpy.h>
 33#include <asm/cacheflush.h>
 34#include <asm/system_misc.h>
 35
 36#include "generic.h"
 37#include "pm.h"
 38
 39static void __iomem *pmc;
 40
 41/*
 42 * FIXME: this is needed to communicate between the pinctrl driver and
 43 * the PM implementation in the machine. Possibly part of the PM
 44 * implementation should be moved down into the pinctrl driver and get
 45 * called as part of the generic suspend/resume path.
 46 */
 47#ifdef CONFIG_PINCTRL_AT91
 48extern void at91_pinctrl_gpio_suspend(void);
 49extern void at91_pinctrl_gpio_resume(void);
 50#endif
 51
 52static struct {
 53	unsigned long uhp_udp_mask;
 54	int memctrl;
 55} at91_pm_data;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 56
 57void __iomem *at91_ramc_base[2];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 58
 59static int at91_pm_valid_state(suspend_state_t state)
 60{
 61	switch (state) {
 62		case PM_SUSPEND_ON:
 63		case PM_SUSPEND_STANDBY:
 64		case PM_SUSPEND_MEM:
 65			return 1;
 66
 67		default:
 68			return 0;
 69	}
 70}
 71
 72
 73static suspend_state_t target_state;
 74
 75/*
 76 * Called after processes are frozen, but before we shutdown devices.
 77 */
 78static int at91_pm_begin(suspend_state_t state)
 79{
 80	target_state = state;
 81	return 0;
 82}
 83
 84/*
 85 * Verify that all the clocks are correct before entering
 86 * slow-clock mode.
 87 */
 88static int at91_pm_verify_clocks(void)
 89{
 90	unsigned long scsr;
 91	int i;
 92
 93	scsr = readl(pmc + AT91_PMC_SCSR);
 94
 95	/* USB must not be using PLLB */
 96	if ((scsr & at91_pm_data.uhp_udp_mask) != 0) {
 97		pr_err("AT91: PM - Suspend-to-RAM with USB still active\n");
 98		return 0;
 
 
 
 
 
 
 
 
 99	}
100
 
101	/* PCK0..PCK3 must be disabled, or configured to use clk32k */
102	for (i = 0; i < 4; i++) {
103		u32 css;
104
105		if ((scsr & (AT91_PMC_PCK0 << i)) == 0)
106			continue;
107		css = readl(pmc + AT91_PMC_PCKR(i)) & AT91_PMC_CSS;
 
108		if (css != AT91_PMC_CSS_SLOW) {
109			pr_err("AT91: PM - Suspend-to-RAM with PCK%d src %d\n", i, css);
110			return 0;
111		}
112	}
 
113
114	return 1;
115}
116
117/*
118 * Call this from platform driver suspend() to see how deeply to suspend.
119 * For example, some controllers (like OHCI) need one of the PLL clocks
120 * in order to act as a wakeup source, and those are not available when
121 * going into slow clock mode.
122 *
123 * REVISIT: generalize as clk_will_be_available(clk)?  Other platforms have
124 * the very same problem (but not using at91 main_clk), and it'd be better
125 * to add one generic API rather than lots of platform-specific ones.
126 */
127int at91_suspend_entering_slow_clock(void)
128{
129	return (target_state == PM_SUSPEND_MEM);
130}
131EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
132
133static void (*at91_suspend_sram_fn)(void __iomem *pmc, void __iomem *ramc0,
 
134			  void __iomem *ramc1, int memctrl);
135
136extern void at91_pm_suspend_in_sram(void __iomem *pmc, void __iomem *ramc0,
 
137			    void __iomem *ramc1, int memctrl);
138extern u32 at91_pm_suspend_in_sram_sz;
 
139
140static void at91_pm_suspend(suspend_state_t state)
141{
142	unsigned int pm_data = at91_pm_data.memctrl;
143
144	pm_data |= (state == PM_SUSPEND_MEM) ?
145				AT91_PM_MODE(AT91_PM_SLOW_CLOCK) : 0;
146
147	flush_cache_all();
148	outer_disable();
 
 
 
 
 
 
149
150	at91_suspend_sram_fn(pmc, at91_ramc_base[0],
151			     at91_ramc_base[1], pm_data);
152
153	outer_resume();
154}
155
156static int at91_pm_enter(suspend_state_t state)
157{
158#ifdef CONFIG_PINCTRL_AT91
159	at91_pinctrl_gpio_suspend();
160#endif
161	switch (state) {
162	/*
163	 * Suspend-to-RAM is like STANDBY plus slow clock mode, so
164	 * drivers must suspend more deeply, the master clock switches
165	 * to the clk32k and turns off the main oscillator
166	 */
167	case PM_SUSPEND_MEM:
168		/*
169		 * Ensure that clocks are in a valid state.
 
 
170		 */
171		if (!at91_pm_verify_clocks())
172			goto error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
173
174		at91_pm_suspend(state);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
175
176		break;
 
 
177
178	/*
179	 * STANDBY mode has *all* drivers suspended; ignores irqs not
180	 * marked as 'wakeup' event sources; and reduces DRAM power.
181	 * But otherwise it's identical to PM_SUSPEND_ON: cpu idle, and
182	 * nothing fancy done with main or cpu clocks.
183	 */
184	case PM_SUSPEND_STANDBY:
185		at91_pm_suspend(state);
186		break;
187
188	case PM_SUSPEND_ON:
189		cpu_do_idle();
190		break;
191
192	default:
193		pr_debug("AT91: PM - bogus suspend state %d\n", state);
194		goto error;
195	}
196
197error:
198	target_state = PM_SUSPEND_ON;
199
200#ifdef CONFIG_PINCTRL_AT91
201	at91_pinctrl_gpio_resume();
202#endif
203	return 0;
204}
205
206/*
207 * Called right prior to thawing processes.
208 */
209static void at91_pm_end(void)
210{
211	target_state = PM_SUSPEND_ON;
212}
213
214
215static const struct platform_suspend_ops at91_pm_ops = {
216	.valid	= at91_pm_valid_state,
217	.begin	= at91_pm_begin,
218	.enter	= at91_pm_enter,
219	.end	= at91_pm_end,
220};
221
222static struct platform_device at91_cpuidle_device = {
223	.name = "cpuidle-at91",
224};
225
226static void at91_pm_set_standby(void (*at91_standby)(void))
227{
228	if (at91_standby)
229		at91_cpuidle_device.dev.platform_data = at91_standby;
230}
231
232/*
233 * The AT91RM9200 goes into self-refresh mode with this command, and will
234 * terminate self-refresh automatically on the next SDRAM access.
235 *
236 * Self-refresh mode is exited as soon as a memory access is made, but we don't
237 * know for sure when that happens. However, we need to restore the low-power
238 * mode if it was enabled before going idle. Restoring low-power mode while
239 * still in self-refresh is "not recommended", but seems to work.
240 */
241static void at91rm9200_standby(void)
242{
243	u32 lpr = at91_ramc_read(0, AT91_MC_SDRAMC_LPR);
244
245	asm volatile(
246		"b    1f\n\t"
247		".align    5\n\t"
248		"1:  mcr    p15, 0, %0, c7, c10, 4\n\t"
249		"    str    %0, [%1, %2]\n\t"
250		"    str    %3, [%1, %4]\n\t"
251		"    mcr    p15, 0, %0, c7, c0, 4\n\t"
252		"    str    %5, [%1, %2]"
253		:
254		: "r" (0), "r" (at91_ramc_base[0]), "r" (AT91_MC_SDRAMC_LPR),
255		  "r" (1), "r" (AT91_MC_SDRAMC_SRR),
256		  "r" (lpr));
257}
258
259/* We manage both DDRAM/SDRAM controllers, we need more than one value to
260 * remember.
261 */
262static void at91_ddr_standby(void)
263{
264	/* Those two values allow us to delay self-refresh activation
265	 * to the maximum. */
266	u32 lpr0, lpr1 = 0;
267	u32 saved_lpr0, saved_lpr1 = 0;
268
269	if (at91_ramc_base[1]) {
270		saved_lpr1 = at91_ramc_read(1, AT91_DDRSDRC_LPR);
271		lpr1 = saved_lpr1 & ~AT91_DDRSDRC_LPCB;
272		lpr1 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
273	}
274
275	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
276	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
277	lpr0 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
278
279	/* self-refresh mode now */
280	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
281	if (at91_ramc_base[1])
282		at91_ramc_write(1, AT91_DDRSDRC_LPR, lpr1);
283
284	cpu_do_idle();
285
286	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
287	if (at91_ramc_base[1])
288		at91_ramc_write(1, AT91_DDRSDRC_LPR, saved_lpr1);
289}
290
291/* We manage both DDRAM/SDRAM controllers, we need more than one value to
292 * remember.
293 */
294static void at91sam9_sdram_standby(void)
295{
296	u32 lpr0, lpr1 = 0;
297	u32 saved_lpr0, saved_lpr1 = 0;
298
299	if (at91_ramc_base[1]) {
300		saved_lpr1 = at91_ramc_read(1, AT91_SDRAMC_LPR);
301		lpr1 = saved_lpr1 & ~AT91_SDRAMC_LPCB;
302		lpr1 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
303	}
304
305	saved_lpr0 = at91_ramc_read(0, AT91_SDRAMC_LPR);
306	lpr0 = saved_lpr0 & ~AT91_SDRAMC_LPCB;
307	lpr0 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
308
309	/* self-refresh mode now */
310	at91_ramc_write(0, AT91_SDRAMC_LPR, lpr0);
311	if (at91_ramc_base[1])
312		at91_ramc_write(1, AT91_SDRAMC_LPR, lpr1);
313
314	cpu_do_idle();
315
316	at91_ramc_write(0, AT91_SDRAMC_LPR, saved_lpr0);
317	if (at91_ramc_base[1])
318		at91_ramc_write(1, AT91_SDRAMC_LPR, saved_lpr1);
319}
320
321static const struct of_device_id const ramc_ids[] __initconst = {
322	{ .compatible = "atmel,at91rm9200-sdramc", .data = at91rm9200_standby },
323	{ .compatible = "atmel,at91sam9260-sdramc", .data = at91sam9_sdram_standby },
324	{ .compatible = "atmel,at91sam9g45-ddramc", .data = at91_ddr_standby },
325	{ .compatible = "atmel,sama5d3-ddramc", .data = at91_ddr_standby },
326	{ /*sentinel*/ }
327};
328
329static __init void at91_dt_ramc(void)
330{
331	struct device_node *np;
332	const struct of_device_id *of_id;
333	int idx = 0;
334	const void *standby = NULL;
335
336	for_each_matching_node_and_match(np, ramc_ids, &of_id) {
337		at91_ramc_base[idx] = of_iomap(np, 0);
338		if (!at91_ramc_base[idx])
339			panic(pr_fmt("unable to map ramc[%d] cpu registers\n"), idx);
340
341		if (!standby)
342			standby = of_id->data;
343
344		idx++;
345	}
346
347	if (!idx)
348		panic(pr_fmt("unable to find compatible ram controller node in dtb\n"));
349
350	if (!standby) {
351		pr_warn("ramc no standby function available\n");
352		return;
353	}
354
355	at91_pm_set_standby(standby);
356}
357
358void at91rm9200_idle(void)
359{
360	/*
361	 * Disable the processor clock.  The processor will be automatically
362	 * re-enabled by an interrupt or by a reset.
363	 */
364	writel(AT91_PMC_PCK, pmc + AT91_PMC_SCDR);
365}
366
367void at91sam9_idle(void)
368{
369	writel(AT91_PMC_PCK, pmc + AT91_PMC_SCDR);
370	cpu_do_idle();
371}
372
373static void __init at91_pm_sram_init(void)
374{
375	struct gen_pool *sram_pool;
376	phys_addr_t sram_pbase;
377	unsigned long sram_base;
378	struct device_node *node;
379	struct platform_device *pdev = NULL;
380
381	for_each_compatible_node(node, NULL, "mmio-sram") {
382		pdev = of_find_device_by_node(node);
383		if (pdev) {
384			of_node_put(node);
385			break;
386		}
387	}
388
389	if (!pdev) {
390		pr_warn("%s: failed to find sram device!\n", __func__);
391		return;
392	}
393
394	sram_pool = gen_pool_get(&pdev->dev, NULL);
395	if (!sram_pool) {
396		pr_warn("%s: sram pool unavailable!\n", __func__);
397		return;
398	}
399
400	sram_base = gen_pool_alloc(sram_pool, at91_pm_suspend_in_sram_sz);
401	if (!sram_base) {
402		pr_warn("%s: unable to alloc sram!\n", __func__);
403		return;
404	}
405
406	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
407	at91_suspend_sram_fn = __arm_ioremap_exec(sram_pbase,
408					at91_pm_suspend_in_sram_sz, false);
409	if (!at91_suspend_sram_fn) {
410		pr_warn("SRAM: Could not map\n");
411		return;
412	}
413
414	/* Copy the pm suspend handler to SRAM */
415	at91_suspend_sram_fn = fncpy(at91_suspend_sram_fn,
416			&at91_pm_suspend_in_sram, at91_pm_suspend_in_sram_sz);
417}
418
419static const struct of_device_id atmel_pmc_ids[] __initconst = {
420	{ .compatible = "atmel,at91rm9200-pmc"  },
421	{ .compatible = "atmel,at91sam9260-pmc" },
422	{ .compatible = "atmel,at91sam9g45-pmc" },
423	{ .compatible = "atmel,at91sam9n12-pmc" },
424	{ .compatible = "atmel,at91sam9x5-pmc" },
425	{ .compatible = "atmel,sama5d3-pmc" },
426	{ .compatible = "atmel,sama5d2-pmc" },
427	{ /* sentinel */ },
428};
429
430static void __init at91_pm_init(void (*pm_idle)(void))
431{
432	struct device_node *pmc_np;
433
434	if (at91_cpuidle_device.dev.platform_data)
435		platform_device_register(&at91_cpuidle_device);
436
437	pmc_np = of_find_matching_node(NULL, atmel_pmc_ids);
438	pmc = of_iomap(pmc_np, 0);
439	if (!pmc) {
440		pr_err("AT91: PM not supported, PMC not found\n");
441		return;
442	}
443
444	if (pm_idle)
445		arm_pm_idle = pm_idle;
446
447	at91_pm_sram_init();
448
449	if (at91_suspend_sram_fn)
450		suspend_set_ops(&at91_pm_ops);
451	else
452		pr_info("AT91: PM not supported, due to no SRAM allocated\n");
453}
454
455void __init at91rm9200_pm_init(void)
456{
457	at91_dt_ramc();
458
459	/*
460	 * AT91RM9200 SDRAM low-power mode cannot be used with self-refresh.
461	 */
462	at91_ramc_write(0, AT91_MC_SDRAMC_LPR, 0);
463
464	at91_pm_data.uhp_udp_mask = AT91RM9200_PMC_UHP | AT91RM9200_PMC_UDP;
465	at91_pm_data.memctrl = AT91_MEMCTRL_MC;
466
467	at91_pm_init(at91rm9200_idle);
468}
469
470void __init at91sam9260_pm_init(void)
471{
472	at91_dt_ramc();
473	at91_pm_data.memctrl = AT91_MEMCTRL_SDRAMC;
474	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP;
475	at91_pm_init(at91sam9_idle);
476}
477
478void __init at91sam9g45_pm_init(void)
479{
480	at91_dt_ramc();
481	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP;
482	at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR;
483	at91_pm_init(at91sam9_idle);
484}
485
486void __init at91sam9x5_pm_init(void)
487{
488	at91_dt_ramc();
489	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP;
490	at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR;
491	at91_pm_init(at91sam9_idle);
492}
493
494void __init sama5_pm_init(void)
495{
496	at91_dt_ramc();
497	at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP;
498	at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR;
499	at91_pm_init(NULL);
500}