xref: /openbmc/linux/arch/arm/mach-omap2/pm34xx.c (revision 94cdda6b)
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 */
56 u16 pm34xx_errata;
57 
58 struct 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 
67 static LIST_HEAD(pwrst_list);
68 
69 static int (*_omap_save_secure_sram)(u32 *addr);
70 void (*omap3_do_wfi_sram)(void);
71 
72 static struct powerdomain *mpu_pwrdm, *neon_pwrdm;
73 static struct powerdomain *core_pwrdm, *per_pwrdm;
74 
75 static 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 
95 static 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  */
112 static 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 
136 static 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 
146 static 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 
167 static 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 
182 static int omap34xx_do_sram_idle(unsigned long save_state)
183 {
184 	omap34xx_cpu_suspend(save_state);
185 	return 0;
186 }
187 
188 void 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 
299 static void omap3_pm_idle(void)
300 {
301 	if (omap_irq_pending())
302 		return;
303 
304 	trace_cpu_idle(1, smp_processor_id());
305 
306 	omap_sram_idle();
307 
308 	trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id());
309 }
310 
311 #ifdef CONFIG_SUSPEND
312 static 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 
332 restore:
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 
354 static 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 
361 void 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 
385 int 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 
396 int 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 
409 static 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  */
436 void 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 
445 static 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 
459 int __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 
570 err3:
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);
576 err2:
577 	free_irq(omap_prcm_event_to_irq("wkup"), NULL);
578 err1:
579 	return ret;
580 }
581