1/*
2 * OMAP3 Power Management Routines
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation
5 * Tony Lindgren <tony@atomide.com>
6 * Jouni Hogander
7 *
8 * Copyright (C) 2007 Texas Instruments, Inc.
9 * Rajendra Nayak <rnayak@ti.com>
10 *
11 * Copyright (C) 2005 Texas Instruments, Inc.
12 * Richard Woodruff <r-woodruff2@ti.com>
13 *
14 * Based on pm.c for omap1
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License version 2 as
18 * published by the Free Software Foundation.
19 */
20
21#include <linux/pm.h>
22#include <linux/suspend.h>
23#include <linux/interrupt.h>
24#include <linux/module.h>
25#include <linux/list.h>
26#include <linux/err.h>
27#include <linux/gpio.h>
28#include <linux/clk.h>
29#include <linux/delay.h>
30#include <linux/slab.h>
31#include <linux/omap-dma.h>
32#include <linux/omap-gpmc.h>
33#include <linux/platform_data/gpio-omap.h>
34
35#include <trace/events/power.h>
36
37#include <asm/fncpy.h>
38#include <asm/suspend.h>
39#include <asm/system_misc.h>
40
41#include "clockdomain.h"
42#include "powerdomain.h"
43#include "soc.h"
44#include "common.h"
45#include "cm3xxx.h"
46#include "cm-regbits-34xx.h"
47#include "prm-regbits-34xx.h"
48#include "prm3xxx.h"
49#include "pm.h"
50#include "sdrc.h"
51#include "sram.h"
52#include "control.h"
53#include "vc.h"
54
55/* pm34xx errata defined in pm.h */
56u16 pm34xx_errata;
57
58struct power_state {
59	struct powerdomain *pwrdm;
60	u32 next_state;
61#ifdef CONFIG_SUSPEND
62	u32 saved_state;
63#endif
64	struct list_head node;
65};
66
67static LIST_HEAD(pwrst_list);
68
69static int (*_omap_save_secure_sram)(u32 *addr);
70void (*omap3_do_wfi_sram)(void);
71
72static struct powerdomain *mpu_pwrdm, *neon_pwrdm;
73static struct powerdomain *core_pwrdm, *per_pwrdm;
74
75static void omap3_core_save_context(void)
76{
77	omap3_ctrl_save_padconf();
78
79	/*
80	 * Force write last pad into memory, as this can fail in some
81	 * cases according to errata 1.157, 1.185
82	 */
83	omap_ctrl_writel(omap_ctrl_readl(OMAP343X_PADCONF_ETK_D14),
84		OMAP343X_CONTROL_MEM_WKUP + 0x2a0);
85
86	/* Save the Interrupt controller context */
87	omap_intc_save_context();
88	/* Save the GPMC context */
89	omap3_gpmc_save_context();
90	/* Save the system control module context, padconf already save above*/
91	omap3_control_save_context();
92	omap_dma_global_context_save();
93}
94
95static void omap3_core_restore_context(void)
96{
97	/* Restore the control module context, padconf restored by h/w */
98	omap3_control_restore_context();
99	/* Restore the GPMC context */
100	omap3_gpmc_restore_context();
101	/* Restore the interrupt controller context */
102	omap_intc_restore_context();
103	omap_dma_global_context_restore();
104}
105
106/*
107 * FIXME: This function should be called before entering off-mode after
108 * OMAP3 secure services have been accessed. Currently it is only called
109 * once during boot sequence, but this works as we are not using secure
110 * services.
111 */
112static void omap3_save_secure_ram_context(void)
113{
114	u32 ret;
115	int mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
116
117	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
118		/*
119		 * MPU next state must be set to POWER_ON temporarily,
120		 * otherwise the WFI executed inside the ROM code
121		 * will hang the system.
122		 */
123		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
124		ret = _omap_save_secure_sram((u32 *)(unsigned long)
125				__pa(omap3_secure_ram_storage));
126		pwrdm_set_next_pwrst(mpu_pwrdm, mpu_next_state);
127		/* Following is for error tracking, it should not happen */
128		if (ret) {
129			pr_err("save_secure_sram() returns %08x\n", ret);
130			while (1)
131				;
132		}
133	}
134}
135
136static irqreturn_t _prcm_int_handle_io(int irq, void *unused)
137{
138	int c;
139
140	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, OMAP3430_ST_IO_MASK |
141				    OMAP3430_ST_IO_CHAIN_MASK);
142
143	return c ? IRQ_HANDLED : IRQ_NONE;
144}
145
146static irqreturn_t _prcm_int_handle_wakeup(int irq, void *unused)
147{
148	int c;
149
150	/*
151	 * Clear all except ST_IO and ST_IO_CHAIN for wkup module,
152	 * these are handled in a separate handler to avoid acking
153	 * IO events before parsing in mux code
154	 */
155	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, ~(OMAP3430_ST_IO_MASK |
156						   OMAP3430_ST_IO_CHAIN_MASK));
157	c += omap_prm_clear_mod_irqs(CORE_MOD, 1, ~0);
158	c += omap_prm_clear_mod_irqs(OMAP3430_PER_MOD, 1, ~0);
159	if (omap_rev() > OMAP3430_REV_ES1_0) {
160		c += omap_prm_clear_mod_irqs(CORE_MOD, 3, ~0);
161		c += omap_prm_clear_mod_irqs(OMAP3430ES2_USBHOST_MOD, 1, ~0);
162	}
163
164	return c ? IRQ_HANDLED : IRQ_NONE;
165}
166
167static void omap34xx_save_context(u32 *save)
168{
169	u32 val;
170
171	/* Read Auxiliary Control Register */
172	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (val));
173	*save++ = 1;
174	*save++ = val;
175
176	/* Read L2 AUX ctrl register */
177	asm("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
178	*save++ = 1;
179	*save++ = val;
180}
181
182static int omap34xx_do_sram_idle(unsigned long save_state)
183{
184	omap34xx_cpu_suspend(save_state);
185	return 0;
186}
187
188void omap_sram_idle(void)
189{
190	/* Variable to tell what needs to be saved and restored
191	 * in omap_sram_idle*/
192	/* save_state = 0 => Nothing to save and restored */
193	/* save_state = 1 => Only L1 and logic lost */
194	/* save_state = 2 => Only L2 lost */
195	/* save_state = 3 => L1, L2 and logic lost */
196	int save_state = 0;
197	int mpu_next_state = PWRDM_POWER_ON;
198	int per_next_state = PWRDM_POWER_ON;
199	int core_next_state = PWRDM_POWER_ON;
200	int per_going_off;
201	int core_prev_state;
202	u32 sdrc_pwr = 0;
203
204	mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
205	switch (mpu_next_state) {
206	case PWRDM_POWER_ON:
207	case PWRDM_POWER_RET:
208		/* No need to save context */
209		save_state = 0;
210		break;
211	case PWRDM_POWER_OFF:
212		save_state = 3;
213		break;
214	default:
215		/* Invalid state */
216		pr_err("Invalid mpu state in sram_idle\n");
217		return;
218	}
219
220	/* NEON control */
221	if (pwrdm_read_pwrst(neon_pwrdm) == PWRDM_POWER_ON)
222		pwrdm_set_next_pwrst(neon_pwrdm, mpu_next_state);
223
224	/* Enable IO-PAD and IO-CHAIN wakeups */
225	per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
226	core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
227
228	pwrdm_pre_transition(NULL);
229
230	/* PER */
231	if (per_next_state < PWRDM_POWER_ON) {
232		per_going_off = (per_next_state == PWRDM_POWER_OFF) ? 1 : 0;
233		omap2_gpio_prepare_for_idle(per_going_off);
234	}
235
236	/* CORE */
237	if (core_next_state < PWRDM_POWER_ON) {
238		if (core_next_state == PWRDM_POWER_OFF) {
239			omap3_core_save_context();
240			omap3_cm_save_context();
241		}
242	}
243
244	/* Configure PMIC signaling for I2C4 or sys_off_mode */
245	omap3_vc_set_pmic_signaling(core_next_state);
246
247	omap3_intc_prepare_idle();
248
249	/*
250	 * On EMU/HS devices ROM code restores a SRDC value
251	 * from scratchpad which has automatic self refresh on timeout
252	 * of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
253	 * Hence store/restore the SDRC_POWER register here.
254	 */
255	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
256	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
257	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
258	    core_next_state == PWRDM_POWER_OFF)
259		sdrc_pwr = sdrc_read_reg(SDRC_POWER);
260
261	/*
262	 * omap3_arm_context is the location where some ARM context
263	 * get saved. The rest is placed on the stack, and restored
264	 * from there before resuming.
265	 */
266	if (save_state)
267		omap34xx_save_context(omap3_arm_context);
268	if (save_state == 1 || save_state == 3)
269		cpu_suspend(save_state, omap34xx_do_sram_idle);
270	else
271		omap34xx_do_sram_idle(save_state);
272
273	/* Restore normal SDRC POWER settings */
274	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
275	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
276	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
277	    core_next_state == PWRDM_POWER_OFF)
278		sdrc_write_reg(sdrc_pwr, SDRC_POWER);
279
280	/* CORE */
281	if (core_next_state < PWRDM_POWER_ON) {
282		core_prev_state = pwrdm_read_prev_pwrst(core_pwrdm);
283		if (core_prev_state == PWRDM_POWER_OFF) {
284			omap3_core_restore_context();
285			omap3_cm_restore_context();
286			omap3_sram_restore_context();
287			omap2_sms_restore_context();
288		}
289	}
290	omap3_intc_resume_idle();
291
292	pwrdm_post_transition(NULL);
293
294	/* PER */
295	if (per_next_state < PWRDM_POWER_ON)
296		omap2_gpio_resume_after_idle();
297}
298
299static void omap3_pm_idle(void)
300{
301	if (omap_irq_pending())
302		return;
303
304	trace_cpu_idle_rcuidle(1, smp_processor_id());
305
306	omap_sram_idle();
307
308	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
309}
310
311#ifdef CONFIG_SUSPEND
312static int omap3_pm_suspend(void)
313{
314	struct power_state *pwrst;
315	int state, ret = 0;
316
317	/* Read current next_pwrsts */
318	list_for_each_entry(pwrst, &pwrst_list, node)
319		pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
320	/* Set ones wanted by suspend */
321	list_for_each_entry(pwrst, &pwrst_list, node) {
322		if (omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state))
323			goto restore;
324		if (pwrdm_clear_all_prev_pwrst(pwrst->pwrdm))
325			goto restore;
326	}
327
328	omap3_intc_suspend();
329
330	omap_sram_idle();
331
332restore:
333	/* Restore next_pwrsts */
334	list_for_each_entry(pwrst, &pwrst_list, node) {
335		state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
336		if (state > pwrst->next_state) {
337			pr_info("Powerdomain (%s) didn't enter target state %d\n",
338				pwrst->pwrdm->name, pwrst->next_state);
339			ret = -1;
340		}
341		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
342	}
343	if (ret)
344		pr_err("Could not enter target state in pm_suspend\n");
345	else
346		pr_info("Successfully put all powerdomains to target state\n");
347
348	return ret;
349}
350#else
351#define omap3_pm_suspend NULL
352#endif /* CONFIG_SUSPEND */
353
354static void __init prcm_setup_regs(void)
355{
356	omap3_ctrl_init();
357
358	omap3_prm_init_pm(cpu_is_omap3630(), omap3_has_iva());
359}
360
361void omap3_pm_off_mode_enable(int enable)
362{
363	struct power_state *pwrst;
364	u32 state;
365
366	if (enable)
367		state = PWRDM_POWER_OFF;
368	else
369		state = PWRDM_POWER_RET;
370
371	list_for_each_entry(pwrst, &pwrst_list, node) {
372		if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) &&
373				pwrst->pwrdm == core_pwrdm &&
374				state == PWRDM_POWER_OFF) {
375			pwrst->next_state = PWRDM_POWER_RET;
376			pr_warn("%s: Core OFF disabled due to errata i583\n",
377				__func__);
378		} else {
379			pwrst->next_state = state;
380		}
381		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
382	}
383}
384
385int omap3_pm_get_suspend_state(struct powerdomain *pwrdm)
386{
387	struct power_state *pwrst;
388
389	list_for_each_entry(pwrst, &pwrst_list, node) {
390		if (pwrst->pwrdm == pwrdm)
391			return pwrst->next_state;
392	}
393	return -EINVAL;
394}
395
396int omap3_pm_set_suspend_state(struct powerdomain *pwrdm, int state)
397{
398	struct power_state *pwrst;
399
400	list_for_each_entry(pwrst, &pwrst_list, node) {
401		if (pwrst->pwrdm == pwrdm) {
402			pwrst->next_state = state;
403			return 0;
404		}
405	}
406	return -EINVAL;
407}
408
409static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
410{
411	struct power_state *pwrst;
412
413	if (!pwrdm->pwrsts)
414		return 0;
415
416	pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
417	if (!pwrst)
418		return -ENOMEM;
419	pwrst->pwrdm = pwrdm;
420	pwrst->next_state = PWRDM_POWER_RET;
421	list_add(&pwrst->node, &pwrst_list);
422
423	if (pwrdm_has_hdwr_sar(pwrdm))
424		pwrdm_enable_hdwr_sar(pwrdm);
425
426	return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
427}
428
429/*
430 * Push functions to SRAM
431 *
432 * The minimum set of functions is pushed to SRAM for execution:
433 * - omap3_do_wfi for erratum i581 WA,
434 * - save_secure_ram_context for security extensions.
435 */
436void omap_push_sram_idle(void)
437{
438	omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
439
440	if (omap_type() != OMAP2_DEVICE_TYPE_GP)
441		_omap_save_secure_sram = omap_sram_push(save_secure_ram_context,
442				save_secure_ram_context_sz);
443}
444
445static void __init pm_errata_configure(void)
446{
447	if (cpu_is_omap3630()) {
448		pm34xx_errata |= PM_RTA_ERRATUM_i608;
449		/* Enable the l2 cache toggling in sleep logic */
450		enable_omap3630_toggle_l2_on_restore();
451		if (omap_rev() < OMAP3630_REV_ES1_2)
452			pm34xx_errata |= (PM_SDRC_WAKEUP_ERRATUM_i583 |
453					  PM_PER_MEMORIES_ERRATUM_i582);
454	} else if (cpu_is_omap34xx()) {
455		pm34xx_errata |= PM_PER_MEMORIES_ERRATUM_i582;
456	}
457}
458
459int __init omap3_pm_init(void)
460{
461	struct power_state *pwrst, *tmp;
462	struct clockdomain *neon_clkdm, *mpu_clkdm, *per_clkdm, *wkup_clkdm;
463	int ret;
464
465	if (!omap3_has_io_chain_ctrl())
466		pr_warn("PM: no software I/O chain control; some wakeups may be lost\n");
467
468	pm_errata_configure();
469
470	/* XXX prcm_setup_regs needs to be before enabling hw
471	 * supervised mode for powerdomains */
472	prcm_setup_regs();
473
474	ret = request_irq(omap_prcm_event_to_irq("wkup"),
475		_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
476
477	if (ret) {
478		pr_err("pm: Failed to request pm_wkup irq\n");
479		goto err1;
480	}
481
482	/* IO interrupt is shared with mux code */
483	ret = request_irq(omap_prcm_event_to_irq("io"),
484		_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
485		omap3_pm_init);
486	enable_irq(omap_prcm_event_to_irq("io"));
487
488	if (ret) {
489		pr_err("pm: Failed to request pm_io irq\n");
490		goto err2;
491	}
492
493	ret = pwrdm_for_each(pwrdms_setup, NULL);
494	if (ret) {
495		pr_err("Failed to setup powerdomains\n");
496		goto err3;
497	}
498
499	(void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
500
501	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
502	if (mpu_pwrdm == NULL) {
503		pr_err("Failed to get mpu_pwrdm\n");
504		ret = -EINVAL;
505		goto err3;
506	}
507
508	neon_pwrdm = pwrdm_lookup("neon_pwrdm");
509	per_pwrdm = pwrdm_lookup("per_pwrdm");
510	core_pwrdm = pwrdm_lookup("core_pwrdm");
511
512	neon_clkdm = clkdm_lookup("neon_clkdm");
513	mpu_clkdm = clkdm_lookup("mpu_clkdm");
514	per_clkdm = clkdm_lookup("per_clkdm");
515	wkup_clkdm = clkdm_lookup("wkup_clkdm");
516
517	omap_common_suspend_init(omap3_pm_suspend);
518
519	arm_pm_idle = omap3_pm_idle;
520	omap3_idle_init();
521
522	/*
523	 * RTA is disabled during initialization as per erratum i608
524	 * it is safer to disable RTA by the bootloader, but we would like
525	 * to be doubly sure here and prevent any mishaps.
526	 */
527	if (IS_PM34XX_ERRATUM(PM_RTA_ERRATUM_i608))
528		omap3630_ctrl_disable_rta();
529
530	/*
531	 * The UART3/4 FIFO and the sidetone memory in McBSP2/3 are
532	 * not correctly reset when the PER powerdomain comes back
533	 * from OFF or OSWR when the CORE powerdomain is kept active.
534	 * See OMAP36xx Erratum i582 "PER Domain reset issue after
535	 * Domain-OFF/OSWR Wakeup".  This wakeup dependency is not a
536	 * complete workaround.  The kernel must also prevent the PER
537	 * powerdomain from going to OSWR/OFF while the CORE
538	 * powerdomain is not going to OSWR/OFF.  And if PER last
539	 * power state was off while CORE last power state was ON, the
540	 * UART3/4 and McBSP2/3 SIDETONE devices need to run a
541	 * self-test using their loopback tests; if that fails, those
542	 * devices are unusable until the PER/CORE can complete a transition
543	 * from ON to OSWR/OFF and then back to ON.
544	 *
545	 * XXX Technically this workaround is only needed if off-mode
546	 * or OSWR is enabled.
547	 */
548	if (IS_PM34XX_ERRATUM(PM_PER_MEMORIES_ERRATUM_i582))
549		clkdm_add_wkdep(per_clkdm, wkup_clkdm);
550
551	clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
552	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
553		omap3_secure_ram_storage =
554			kmalloc(0x803F, GFP_KERNEL);
555		if (!omap3_secure_ram_storage)
556			pr_err("Memory allocation failed when allocating for secure sram context\n");
557
558		local_irq_disable();
559
560		omap_dma_global_context_save();
561		omap3_save_secure_ram_context();
562		omap_dma_global_context_restore();
563
564		local_irq_enable();
565	}
566
567	omap3_save_scratchpad_contents();
568	return ret;
569
570err3:
571	list_for_each_entry_safe(pwrst, tmp, &pwrst_list, node) {
572		list_del(&pwrst->node);
573		kfree(pwrst);
574	}
575	free_irq(omap_prcm_event_to_irq("io"), omap3_pm_init);
576err2:
577	free_irq(omap_prcm_event_to_irq("wkup"), NULL);
578err1:
579	return ret;
580}
581