xref: /openbmc/linux/arch/arm/mach-omap2/pm34xx.c (revision ca460cc2)
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/platform_data/gpio-omap.h>
33 
34 #include <trace/events/power.h>
35 
36 #include <asm/fncpy.h>
37 #include <asm/suspend.h>
38 #include <asm/system_misc.h>
39 
40 #include "clockdomain.h"
41 #include "powerdomain.h"
42 #include "soc.h"
43 #include "common.h"
44 #include "cm3xxx.h"
45 #include "cm-regbits-34xx.h"
46 #include "gpmc.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 = omap3xxx_prm_clear_mod_irqs(WKUP_MOD, 1,
141 					~(OMAP3430_ST_IO_MASK |
142 					  OMAP3430_ST_IO_CHAIN_MASK));
143 
144 	return c ? IRQ_HANDLED : IRQ_NONE;
145 }
146 
147 static irqreturn_t _prcm_int_handle_wakeup(int irq, void *unused)
148 {
149 	int c;
150 
151 	/*
152 	 * Clear all except ST_IO and ST_IO_CHAIN for wkup module,
153 	 * these are handled in a separate handler to avoid acking
154 	 * IO events before parsing in mux code
155 	 */
156 	c = omap3xxx_prm_clear_mod_irqs(WKUP_MOD, 1,
157 					OMAP3430_ST_IO_MASK |
158 					OMAP3430_ST_IO_CHAIN_MASK);
159 	c += omap3xxx_prm_clear_mod_irqs(CORE_MOD, 1, 0);
160 	c += omap3xxx_prm_clear_mod_irqs(OMAP3430_PER_MOD, 1, 0);
161 	if (omap_rev() > OMAP3430_REV_ES1_0) {
162 		c += omap3xxx_prm_clear_mod_irqs(CORE_MOD, 3, 0);
163 		c += omap3xxx_prm_clear_mod_irqs(OMAP3430ES2_USBHOST_MOD, 1, 0);
164 	}
165 
166 	return c ? IRQ_HANDLED : IRQ_NONE;
167 }
168 
169 static void omap34xx_save_context(u32 *save)
170 {
171 	u32 val;
172 
173 	/* Read Auxiliary Control Register */
174 	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (val));
175 	*save++ = 1;
176 	*save++ = val;
177 
178 	/* Read L2 AUX ctrl register */
179 	asm("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
180 	*save++ = 1;
181 	*save++ = val;
182 }
183 
184 static int omap34xx_do_sram_idle(unsigned long save_state)
185 {
186 	omap34xx_cpu_suspend(save_state);
187 	return 0;
188 }
189 
190 void omap_sram_idle(void)
191 {
192 	/* Variable to tell what needs to be saved and restored
193 	 * in omap_sram_idle*/
194 	/* save_state = 0 => Nothing to save and restored */
195 	/* save_state = 1 => Only L1 and logic lost */
196 	/* save_state = 2 => Only L2 lost */
197 	/* save_state = 3 => L1, L2 and logic lost */
198 	int save_state = 0;
199 	int mpu_next_state = PWRDM_POWER_ON;
200 	int per_next_state = PWRDM_POWER_ON;
201 	int core_next_state = PWRDM_POWER_ON;
202 	int per_going_off;
203 	int core_prev_state;
204 	u32 sdrc_pwr = 0;
205 
206 	mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
207 	switch (mpu_next_state) {
208 	case PWRDM_POWER_ON:
209 	case PWRDM_POWER_RET:
210 		/* No need to save context */
211 		save_state = 0;
212 		break;
213 	case PWRDM_POWER_OFF:
214 		save_state = 3;
215 		break;
216 	default:
217 		/* Invalid state */
218 		pr_err("Invalid mpu state in sram_idle\n");
219 		return;
220 	}
221 
222 	/* NEON control */
223 	if (pwrdm_read_pwrst(neon_pwrdm) == PWRDM_POWER_ON)
224 		pwrdm_set_next_pwrst(neon_pwrdm, mpu_next_state);
225 
226 	/* Enable IO-PAD and IO-CHAIN wakeups */
227 	per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
228 	core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
229 
230 	pwrdm_pre_transition(NULL);
231 
232 	/* PER */
233 	if (per_next_state < PWRDM_POWER_ON) {
234 		per_going_off = (per_next_state == PWRDM_POWER_OFF) ? 1 : 0;
235 		omap2_gpio_prepare_for_idle(per_going_off);
236 	}
237 
238 	/* CORE */
239 	if (core_next_state < PWRDM_POWER_ON) {
240 		if (core_next_state == PWRDM_POWER_OFF) {
241 			omap3_core_save_context();
242 			omap3_cm_save_context();
243 		}
244 	}
245 
246 	/* Configure PMIC signaling for I2C4 or sys_off_mode */
247 	omap3_vc_set_pmic_signaling(core_next_state);
248 
249 	omap3_intc_prepare_idle();
250 
251 	/*
252 	 * On EMU/HS devices ROM code restores a SRDC value
253 	 * from scratchpad which has automatic self refresh on timeout
254 	 * of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
255 	 * Hence store/restore the SDRC_POWER register here.
256 	 */
257 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
258 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
259 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
260 	    core_next_state == PWRDM_POWER_OFF)
261 		sdrc_pwr = sdrc_read_reg(SDRC_POWER);
262 
263 	/*
264 	 * omap3_arm_context is the location where some ARM context
265 	 * get saved. The rest is placed on the stack, and restored
266 	 * from there before resuming.
267 	 */
268 	if (save_state)
269 		omap34xx_save_context(omap3_arm_context);
270 	if (save_state == 1 || save_state == 3)
271 		cpu_suspend(save_state, omap34xx_do_sram_idle);
272 	else
273 		omap34xx_do_sram_idle(save_state);
274 
275 	/* Restore normal SDRC POWER settings */
276 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
277 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
278 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
279 	    core_next_state == PWRDM_POWER_OFF)
280 		sdrc_write_reg(sdrc_pwr, SDRC_POWER);
281 
282 	/* CORE */
283 	if (core_next_state < PWRDM_POWER_ON) {
284 		core_prev_state = pwrdm_read_prev_pwrst(core_pwrdm);
285 		if (core_prev_state == PWRDM_POWER_OFF) {
286 			omap3_core_restore_context();
287 			omap3_cm_restore_context();
288 			omap3_sram_restore_context();
289 			omap2_sms_restore_context();
290 		}
291 	}
292 	omap3_intc_resume_idle();
293 
294 	pwrdm_post_transition(NULL);
295 
296 	/* PER */
297 	if (per_next_state < PWRDM_POWER_ON)
298 		omap2_gpio_resume_after_idle();
299 }
300 
301 static void omap3_pm_idle(void)
302 {
303 	if (omap_irq_pending())
304 		return;
305 
306 	trace_cpu_idle(1, smp_processor_id());
307 
308 	omap_sram_idle();
309 
310 	trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id());
311 }
312 
313 #ifdef CONFIG_SUSPEND
314 static int omap3_pm_suspend(void)
315 {
316 	struct power_state *pwrst;
317 	int state, ret = 0;
318 
319 	/* Read current next_pwrsts */
320 	list_for_each_entry(pwrst, &pwrst_list, node)
321 		pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
322 	/* Set ones wanted by suspend */
323 	list_for_each_entry(pwrst, &pwrst_list, node) {
324 		if (omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state))
325 			goto restore;
326 		if (pwrdm_clear_all_prev_pwrst(pwrst->pwrdm))
327 			goto restore;
328 	}
329 
330 	omap3_intc_suspend();
331 
332 	omap_sram_idle();
333 
334 restore:
335 	/* Restore next_pwrsts */
336 	list_for_each_entry(pwrst, &pwrst_list, node) {
337 		state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
338 		if (state > pwrst->next_state) {
339 			pr_info("Powerdomain (%s) didn't enter target state %d\n",
340 				pwrst->pwrdm->name, pwrst->next_state);
341 			ret = -1;
342 		}
343 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
344 	}
345 	if (ret)
346 		pr_err("Could not enter target state in pm_suspend\n");
347 	else
348 		pr_info("Successfully put all powerdomains to target state\n");
349 
350 	return ret;
351 }
352 #else
353 #define omap3_pm_suspend NULL
354 #endif /* CONFIG_SUSPEND */
355 
356 static void __init prcm_setup_regs(void)
357 {
358 	omap3_ctrl_init();
359 
360 	omap3_prm_init_pm(cpu_is_omap3630(), omap3_has_iva());
361 }
362 
363 void omap3_pm_off_mode_enable(int enable)
364 {
365 	struct power_state *pwrst;
366 	u32 state;
367 
368 	if (enable)
369 		state = PWRDM_POWER_OFF;
370 	else
371 		state = PWRDM_POWER_RET;
372 
373 	list_for_each_entry(pwrst, &pwrst_list, node) {
374 		if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) &&
375 				pwrst->pwrdm == core_pwrdm &&
376 				state == PWRDM_POWER_OFF) {
377 			pwrst->next_state = PWRDM_POWER_RET;
378 			pr_warn("%s: Core OFF disabled due to errata i583\n",
379 				__func__);
380 		} else {
381 			pwrst->next_state = state;
382 		}
383 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
384 	}
385 }
386 
387 int omap3_pm_get_suspend_state(struct powerdomain *pwrdm)
388 {
389 	struct power_state *pwrst;
390 
391 	list_for_each_entry(pwrst, &pwrst_list, node) {
392 		if (pwrst->pwrdm == pwrdm)
393 			return pwrst->next_state;
394 	}
395 	return -EINVAL;
396 }
397 
398 int omap3_pm_set_suspend_state(struct powerdomain *pwrdm, int state)
399 {
400 	struct power_state *pwrst;
401 
402 	list_for_each_entry(pwrst, &pwrst_list, node) {
403 		if (pwrst->pwrdm == pwrdm) {
404 			pwrst->next_state = state;
405 			return 0;
406 		}
407 	}
408 	return -EINVAL;
409 }
410 
411 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
412 {
413 	struct power_state *pwrst;
414 
415 	if (!pwrdm->pwrsts)
416 		return 0;
417 
418 	pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
419 	if (!pwrst)
420 		return -ENOMEM;
421 	pwrst->pwrdm = pwrdm;
422 	pwrst->next_state = PWRDM_POWER_RET;
423 	list_add(&pwrst->node, &pwrst_list);
424 
425 	if (pwrdm_has_hdwr_sar(pwrdm))
426 		pwrdm_enable_hdwr_sar(pwrdm);
427 
428 	return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
429 }
430 
431 /*
432  * Push functions to SRAM
433  *
434  * The minimum set of functions is pushed to SRAM for execution:
435  * - omap3_do_wfi for erratum i581 WA,
436  * - save_secure_ram_context for security extensions.
437  */
438 void omap_push_sram_idle(void)
439 {
440 	omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
441 
442 	if (omap_type() != OMAP2_DEVICE_TYPE_GP)
443 		_omap_save_secure_sram = omap_sram_push(save_secure_ram_context,
444 				save_secure_ram_context_sz);
445 }
446 
447 static void __init pm_errata_configure(void)
448 {
449 	if (cpu_is_omap3630()) {
450 		pm34xx_errata |= PM_RTA_ERRATUM_i608;
451 		/* Enable the l2 cache toggling in sleep logic */
452 		enable_omap3630_toggle_l2_on_restore();
453 		if (omap_rev() < OMAP3630_REV_ES1_2)
454 			pm34xx_errata |= (PM_SDRC_WAKEUP_ERRATUM_i583 |
455 					  PM_PER_MEMORIES_ERRATUM_i582);
456 	} else if (cpu_is_omap34xx()) {
457 		pm34xx_errata |= PM_PER_MEMORIES_ERRATUM_i582;
458 	}
459 }
460 
461 int __init omap3_pm_init(void)
462 {
463 	struct power_state *pwrst, *tmp;
464 	struct clockdomain *neon_clkdm, *mpu_clkdm, *per_clkdm, *wkup_clkdm;
465 	int ret;
466 
467 	if (!omap3_has_io_chain_ctrl())
468 		pr_warn("PM: no software I/O chain control; some wakeups may be lost\n");
469 
470 	pm_errata_configure();
471 
472 	/* XXX prcm_setup_regs needs to be before enabling hw
473 	 * supervised mode for powerdomains */
474 	prcm_setup_regs();
475 
476 	ret = request_irq(omap_prcm_event_to_irq("wkup"),
477 		_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
478 
479 	if (ret) {
480 		pr_err("pm: Failed to request pm_wkup irq\n");
481 		goto err1;
482 	}
483 
484 	/* IO interrupt is shared with mux code */
485 	ret = request_irq(omap_prcm_event_to_irq("io"),
486 		_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
487 		omap3_pm_init);
488 	enable_irq(omap_prcm_event_to_irq("io"));
489 
490 	if (ret) {
491 		pr_err("pm: Failed to request pm_io irq\n");
492 		goto err2;
493 	}
494 
495 	ret = pwrdm_for_each(pwrdms_setup, NULL);
496 	if (ret) {
497 		pr_err("Failed to setup powerdomains\n");
498 		goto err3;
499 	}
500 
501 	(void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
502 
503 	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
504 	if (mpu_pwrdm == NULL) {
505 		pr_err("Failed to get mpu_pwrdm\n");
506 		ret = -EINVAL;
507 		goto err3;
508 	}
509 
510 	neon_pwrdm = pwrdm_lookup("neon_pwrdm");
511 	per_pwrdm = pwrdm_lookup("per_pwrdm");
512 	core_pwrdm = pwrdm_lookup("core_pwrdm");
513 
514 	neon_clkdm = clkdm_lookup("neon_clkdm");
515 	mpu_clkdm = clkdm_lookup("mpu_clkdm");
516 	per_clkdm = clkdm_lookup("per_clkdm");
517 	wkup_clkdm = clkdm_lookup("wkup_clkdm");
518 
519 	omap_common_suspend_init(omap3_pm_suspend);
520 
521 	arm_pm_idle = omap3_pm_idle;
522 	omap3_idle_init();
523 
524 	/*
525 	 * RTA is disabled during initialization as per erratum i608
526 	 * it is safer to disable RTA by the bootloader, but we would like
527 	 * to be doubly sure here and prevent any mishaps.
528 	 */
529 	if (IS_PM34XX_ERRATUM(PM_RTA_ERRATUM_i608))
530 		omap3630_ctrl_disable_rta();
531 
532 	/*
533 	 * The UART3/4 FIFO and the sidetone memory in McBSP2/3 are
534 	 * not correctly reset when the PER powerdomain comes back
535 	 * from OFF or OSWR when the CORE powerdomain is kept active.
536 	 * See OMAP36xx Erratum i582 "PER Domain reset issue after
537 	 * Domain-OFF/OSWR Wakeup".  This wakeup dependency is not a
538 	 * complete workaround.  The kernel must also prevent the PER
539 	 * powerdomain from going to OSWR/OFF while the CORE
540 	 * powerdomain is not going to OSWR/OFF.  And if PER last
541 	 * power state was off while CORE last power state was ON, the
542 	 * UART3/4 and McBSP2/3 SIDETONE devices need to run a
543 	 * self-test using their loopback tests; if that fails, those
544 	 * devices are unusable until the PER/CORE can complete a transition
545 	 * from ON to OSWR/OFF and then back to ON.
546 	 *
547 	 * XXX Technically this workaround is only needed if off-mode
548 	 * or OSWR is enabled.
549 	 */
550 	if (IS_PM34XX_ERRATUM(PM_PER_MEMORIES_ERRATUM_i582))
551 		clkdm_add_wkdep(per_clkdm, wkup_clkdm);
552 
553 	clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
554 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
555 		omap3_secure_ram_storage =
556 			kmalloc(0x803F, GFP_KERNEL);
557 		if (!omap3_secure_ram_storage)
558 			pr_err("Memory allocation failed when allocating for secure sram context\n");
559 
560 		local_irq_disable();
561 
562 		omap_dma_global_context_save();
563 		omap3_save_secure_ram_context();
564 		omap_dma_global_context_restore();
565 
566 		local_irq_enable();
567 	}
568 
569 	omap3_save_scratchpad_contents();
570 	return ret;
571 
572 err3:
573 	list_for_each_entry_safe(pwrst, tmp, &pwrst_list, node) {
574 		list_del(&pwrst->node);
575 		kfree(pwrst);
576 	}
577 	free_irq(omap_prcm_event_to_irq("io"), omap3_pm_init);
578 err2:
579 	free_irq(omap_prcm_event_to_irq("wkup"), NULL);
580 err1:
581 	return ret;
582 }
583