xref: /openbmc/linux/arch/arm/mach-omap2/pm34xx.c (revision 36fe4655)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OMAP3 Power Management Routines
4  *
5  * Copyright (C) 2006-2008 Nokia Corporation
6  * Tony Lindgren <tony@atomide.com>
7  * Jouni Hogander
8  *
9  * Copyright (C) 2007 Texas Instruments, Inc.
10  * Rajendra Nayak <rnayak@ti.com>
11  *
12  * Copyright (C) 2005 Texas Instruments, Inc.
13  * Richard Woodruff <r-woodruff2@ti.com>
14  *
15  * Based on pm.c for omap1
16  */
17 
18 #include <linux/cpu_pm.h>
19 #include <linux/pm.h>
20 #include <linux/suspend.h>
21 #include <linux/interrupt.h>
22 #include <linux/module.h>
23 #include <linux/list.h>
24 #include <linux/err.h>
25 #include <linux/clk.h>
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 #include <linux/of.h>
29 #include <linux/omap-gpmc.h>
30 
31 #include <trace/events/power.h>
32 
33 #include <asm/fncpy.h>
34 #include <asm/suspend.h>
35 #include <asm/system_misc.h>
36 
37 #include "clockdomain.h"
38 #include "powerdomain.h"
39 #include "soc.h"
40 #include "common.h"
41 #include "cm3xxx.h"
42 #include "cm-regbits-34xx.h"
43 #include "prm-regbits-34xx.h"
44 #include "prm3xxx.h"
45 #include "pm.h"
46 #include "sdrc.h"
47 #include "omap-secure.h"
48 #include "sram.h"
49 #include "control.h"
50 #include "vc.h"
51 
52 /* pm34xx errata defined in pm.h */
53 u16 pm34xx_errata;
54 
55 struct power_state {
56 	struct powerdomain *pwrdm;
57 	u32 next_state;
58 #ifdef CONFIG_SUSPEND
59 	u32 saved_state;
60 #endif
61 	struct list_head node;
62 };
63 
64 static LIST_HEAD(pwrst_list);
65 
66 void (*omap3_do_wfi_sram)(void);
67 
68 static struct powerdomain *mpu_pwrdm, *neon_pwrdm;
69 static struct powerdomain *core_pwrdm, *per_pwrdm;
70 
71 static void omap3_core_save_context(void)
72 {
73 	omap3_ctrl_save_padconf();
74 
75 	/*
76 	 * Force write last pad into memory, as this can fail in some
77 	 * cases according to errata 1.157, 1.185
78 	 */
79 	omap_ctrl_writel(omap_ctrl_readl(OMAP343X_PADCONF_ETK_D14),
80 		OMAP343X_CONTROL_MEM_WKUP + 0x2a0);
81 
82 	/* Save the Interrupt controller context */
83 	omap_intc_save_context();
84 	/* Save the GPMC context */
85 	omap3_gpmc_save_context();
86 	/* Save the system control module context, padconf already save above*/
87 	omap3_control_save_context();
88 }
89 
90 static void omap3_core_restore_context(void)
91 {
92 	/* Restore the control module context, padconf restored by h/w */
93 	omap3_control_restore_context();
94 	/* Restore the GPMC context */
95 	omap3_gpmc_restore_context();
96 	/* Restore the interrupt controller context */
97 	omap_intc_restore_context();
98 }
99 
100 /*
101  * FIXME: This function should be called before entering off-mode after
102  * OMAP3 secure services have been accessed. Currently it is only called
103  * once during boot sequence, but this works as we are not using secure
104  * services.
105  */
106 static void omap3_save_secure_ram_context(void)
107 {
108 	u32 ret;
109 	int mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
110 
111 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
112 		/*
113 		 * MPU next state must be set to POWER_ON temporarily,
114 		 * otherwise the WFI executed inside the ROM code
115 		 * will hang the system.
116 		 */
117 		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
118 		ret = omap3_save_secure_ram(omap3_secure_ram_storage,
119 					    OMAP3_SAVE_SECURE_RAM_SZ);
120 		pwrdm_set_next_pwrst(mpu_pwrdm, mpu_next_state);
121 		/* Following is for error tracking, it should not happen */
122 		if (ret) {
123 			pr_err("save_secure_sram() returns %08x\n", ret);
124 			while (1)
125 				;
126 		}
127 	}
128 }
129 
130 static irqreturn_t _prcm_int_handle_io(int irq, void *unused)
131 {
132 	int c;
133 
134 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, OMAP3430_ST_IO_MASK |
135 				    OMAP3430_ST_IO_CHAIN_MASK);
136 
137 	return c ? IRQ_HANDLED : IRQ_NONE;
138 }
139 
140 static irqreturn_t _prcm_int_handle_wakeup(int irq, void *unused)
141 {
142 	int c;
143 
144 	/*
145 	 * Clear all except ST_IO and ST_IO_CHAIN for wkup module,
146 	 * these are handled in a separate handler to avoid acking
147 	 * IO events before parsing in mux code
148 	 */
149 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, ~(OMAP3430_ST_IO_MASK |
150 						   OMAP3430_ST_IO_CHAIN_MASK));
151 	c += omap_prm_clear_mod_irqs(CORE_MOD, 1, ~0);
152 	c += omap_prm_clear_mod_irqs(OMAP3430_PER_MOD, 1, ~0);
153 	if (omap_rev() > OMAP3430_REV_ES1_0) {
154 		c += omap_prm_clear_mod_irqs(CORE_MOD, 3, ~0);
155 		c += omap_prm_clear_mod_irqs(OMAP3430ES2_USBHOST_MOD, 1, ~0);
156 	}
157 
158 	return c ? IRQ_HANDLED : IRQ_NONE;
159 }
160 
161 static void omap34xx_save_context(u32 *save)
162 {
163 	u32 val;
164 
165 	/* Read Auxiliary Control Register */
166 	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (val));
167 	*save++ = 1;
168 	*save++ = val;
169 
170 	/* Read L2 AUX ctrl register */
171 	asm("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
172 	*save++ = 1;
173 	*save++ = val;
174 }
175 
176 static int omap34xx_do_sram_idle(unsigned long save_state)
177 {
178 	omap34xx_cpu_suspend(save_state);
179 	return 0;
180 }
181 
182 void omap_sram_idle(void)
183 {
184 	/* Variable to tell what needs to be saved and restored
185 	 * in omap_sram_idle*/
186 	/* save_state = 0 => Nothing to save and restored */
187 	/* save_state = 1 => Only L1 and logic lost */
188 	/* save_state = 2 => Only L2 lost */
189 	/* save_state = 3 => L1, L2 and logic lost */
190 	int save_state = 0;
191 	int mpu_next_state = PWRDM_POWER_ON;
192 	int per_next_state = PWRDM_POWER_ON;
193 	int core_next_state = PWRDM_POWER_ON;
194 	u32 sdrc_pwr = 0;
195 	int error;
196 
197 	mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
198 	switch (mpu_next_state) {
199 	case PWRDM_POWER_ON:
200 	case PWRDM_POWER_RET:
201 		/* No need to save context */
202 		save_state = 0;
203 		break;
204 	case PWRDM_POWER_OFF:
205 		save_state = 3;
206 		break;
207 	default:
208 		/* Invalid state */
209 		pr_err("Invalid mpu state in sram_idle\n");
210 		return;
211 	}
212 
213 	/* NEON control */
214 	if (pwrdm_read_pwrst(neon_pwrdm) == PWRDM_POWER_ON)
215 		pwrdm_set_next_pwrst(neon_pwrdm, mpu_next_state);
216 
217 	/* Enable IO-PAD and IO-CHAIN wakeups */
218 	per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
219 	core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
220 
221 	pwrdm_pre_transition(NULL);
222 
223 	/* PER */
224 	if (per_next_state == PWRDM_POWER_OFF) {
225 		error = cpu_cluster_pm_enter();
226 		if (error)
227 			return;
228 	}
229 
230 	/* CORE */
231 	if (core_next_state < PWRDM_POWER_ON) {
232 		if (core_next_state == PWRDM_POWER_OFF) {
233 			omap3_core_save_context();
234 			omap3_cm_save_context();
235 		}
236 	}
237 
238 	/* Configure PMIC signaling for I2C4 or sys_off_mode */
239 	omap3_vc_set_pmic_signaling(core_next_state);
240 
241 	omap3_intc_prepare_idle();
242 
243 	/*
244 	 * On EMU/HS devices ROM code restores a SRDC value
245 	 * from scratchpad which has automatic self refresh on timeout
246 	 * of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
247 	 * Hence store/restore the SDRC_POWER register here.
248 	 */
249 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
250 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
251 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
252 	    core_next_state == PWRDM_POWER_OFF)
253 		sdrc_pwr = sdrc_read_reg(SDRC_POWER);
254 
255 	/*
256 	 * omap3_arm_context is the location where some ARM context
257 	 * get saved. The rest is placed on the stack, and restored
258 	 * from there before resuming.
259 	 */
260 	if (save_state)
261 		omap34xx_save_context(omap3_arm_context);
262 	if (save_state == 1 || save_state == 3)
263 		cpu_suspend(save_state, omap34xx_do_sram_idle);
264 	else
265 		omap34xx_do_sram_idle(save_state);
266 
267 	/* Restore normal SDRC POWER settings */
268 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
269 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
270 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
271 	    core_next_state == PWRDM_POWER_OFF)
272 		sdrc_write_reg(sdrc_pwr, SDRC_POWER);
273 
274 	/* CORE */
275 	if (core_next_state < PWRDM_POWER_ON &&
276 	    pwrdm_read_prev_pwrst(core_pwrdm) == PWRDM_POWER_OFF) {
277 		omap3_core_restore_context();
278 		omap3_cm_restore_context();
279 		omap3_sram_restore_context();
280 		omap2_sms_restore_context();
281 	} else {
282 		/*
283 		 * In off-mode resume path above, omap3_core_restore_context
284 		 * also handles the INTC autoidle restore done here so limit
285 		 * this to non-off mode resume paths so we don't do it twice.
286 		 */
287 		omap3_intc_resume_idle();
288 	}
289 
290 	pwrdm_post_transition(NULL);
291 
292 	/* PER */
293 	if (per_next_state == PWRDM_POWER_OFF)
294 		cpu_cluster_pm_exit();
295 }
296 
297 static void omap3_pm_idle(void)
298 {
299 	if (omap_irq_pending())
300 		return;
301 
302 	omap_sram_idle();
303 }
304 
305 #ifdef CONFIG_SUSPEND
306 static int omap3_pm_suspend(void)
307 {
308 	struct power_state *pwrst;
309 	int state, ret = 0;
310 
311 	/* Read current next_pwrsts */
312 	list_for_each_entry(pwrst, &pwrst_list, node)
313 		pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
314 	/* Set ones wanted by suspend */
315 	list_for_each_entry(pwrst, &pwrst_list, node) {
316 		if (omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state))
317 			goto restore;
318 		if (pwrdm_clear_all_prev_pwrst(pwrst->pwrdm))
319 			goto restore;
320 	}
321 
322 	omap3_intc_suspend();
323 
324 	omap_sram_idle();
325 
326 restore:
327 	/* Restore next_pwrsts */
328 	list_for_each_entry(pwrst, &pwrst_list, node) {
329 		state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
330 		if (state > pwrst->next_state) {
331 			pr_info("Powerdomain (%s) didn't enter target state %d\n",
332 				pwrst->pwrdm->name, pwrst->next_state);
333 			ret = -1;
334 		}
335 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
336 	}
337 	if (ret)
338 		pr_err("Could not enter target state in pm_suspend\n");
339 	else
340 		pr_info("Successfully put all powerdomains to target state\n");
341 
342 	return ret;
343 }
344 #else
345 #define omap3_pm_suspend NULL
346 #endif /* CONFIG_SUSPEND */
347 
348 static void __init prcm_setup_regs(void)
349 {
350 	omap3_ctrl_init();
351 
352 	omap3_prm_init_pm(cpu_is_omap3630(), omap3_has_iva());
353 }
354 
355 void omap3_pm_off_mode_enable(int enable)
356 {
357 	struct power_state *pwrst;
358 	u32 state;
359 
360 	if (enable)
361 		state = PWRDM_POWER_OFF;
362 	else
363 		state = PWRDM_POWER_RET;
364 
365 	list_for_each_entry(pwrst, &pwrst_list, node) {
366 		if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) &&
367 				pwrst->pwrdm == core_pwrdm &&
368 				state == PWRDM_POWER_OFF) {
369 			pwrst->next_state = PWRDM_POWER_RET;
370 			pr_warn("%s: Core OFF disabled due to errata i583\n",
371 				__func__);
372 		} else {
373 			pwrst->next_state = state;
374 		}
375 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
376 	}
377 }
378 
379 int omap3_pm_get_suspend_state(struct powerdomain *pwrdm)
380 {
381 	struct power_state *pwrst;
382 
383 	list_for_each_entry(pwrst, &pwrst_list, node) {
384 		if (pwrst->pwrdm == pwrdm)
385 			return pwrst->next_state;
386 	}
387 	return -EINVAL;
388 }
389 
390 int omap3_pm_set_suspend_state(struct powerdomain *pwrdm, int state)
391 {
392 	struct power_state *pwrst;
393 
394 	list_for_each_entry(pwrst, &pwrst_list, node) {
395 		if (pwrst->pwrdm == pwrdm) {
396 			pwrst->next_state = state;
397 			return 0;
398 		}
399 	}
400 	return -EINVAL;
401 }
402 
403 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
404 {
405 	struct power_state *pwrst;
406 
407 	if (!pwrdm->pwrsts)
408 		return 0;
409 
410 	pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
411 	if (!pwrst)
412 		return -ENOMEM;
413 	pwrst->pwrdm = pwrdm;
414 
415 	if (enable_off_mode)
416 		pwrst->next_state = PWRDM_POWER_OFF;
417 	else
418 		pwrst->next_state = PWRDM_POWER_RET;
419 
420 	list_add(&pwrst->node, &pwrst_list);
421 
422 	if (pwrdm_has_hdwr_sar(pwrdm))
423 		pwrdm_enable_hdwr_sar(pwrdm);
424 
425 	return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
426 }
427 
428 /*
429  * Push functions to SRAM
430  *
431  * The minimum set of functions is pushed to SRAM for execution:
432  * - omap3_do_wfi for erratum i581 WA,
433  */
434 void omap_push_sram_idle(void)
435 {
436 	omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
437 }
438 
439 static void __init pm_errata_configure(void)
440 {
441 	if (cpu_is_omap3630()) {
442 		pm34xx_errata |= PM_RTA_ERRATUM_i608;
443 		/* Enable the l2 cache toggling in sleep logic */
444 		enable_omap3630_toggle_l2_on_restore();
445 		if (omap_rev() < OMAP3630_REV_ES1_2)
446 			pm34xx_errata |= (PM_SDRC_WAKEUP_ERRATUM_i583 |
447 					  PM_PER_MEMORIES_ERRATUM_i582);
448 	} else if (cpu_is_omap34xx()) {
449 		pm34xx_errata |= PM_PER_MEMORIES_ERRATUM_i582;
450 	}
451 }
452 
453 static void __init omap3_pm_check_pmic(void)
454 {
455 	struct device_node *np;
456 
457 	np = of_find_compatible_node(NULL, NULL, "ti,twl4030-power-idle");
458 	if (!np)
459 		np = of_find_compatible_node(NULL, NULL, "ti,twl4030-power-idle-osc-off");
460 
461 	if (np) {
462 		of_node_put(np);
463 		enable_off_mode = 1;
464 	} else {
465 		enable_off_mode = 0;
466 	}
467 }
468 
469 int __init omap3_pm_init(void)
470 {
471 	struct power_state *pwrst, *tmp;
472 	struct clockdomain *neon_clkdm, *mpu_clkdm, *per_clkdm, *wkup_clkdm;
473 	int ret;
474 
475 	if (!omap3_has_io_chain_ctrl())
476 		pr_warn("PM: no software I/O chain control; some wakeups may be lost\n");
477 
478 	pm_errata_configure();
479 
480 	/* XXX prcm_setup_regs needs to be before enabling hw
481 	 * supervised mode for powerdomains */
482 	prcm_setup_regs();
483 
484 	ret = request_irq(omap_prcm_event_to_irq("wkup"),
485 		_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
486 
487 	if (ret) {
488 		pr_err("pm: Failed to request pm_wkup irq\n");
489 		goto err1;
490 	}
491 
492 	/* IO interrupt is shared with mux code */
493 	ret = request_irq(omap_prcm_event_to_irq("io"),
494 		_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
495 		omap3_pm_init);
496 
497 	if (ret) {
498 		pr_err("pm: Failed to request pm_io irq\n");
499 		goto err2;
500 	}
501 
502 	omap3_pm_check_pmic();
503 
504 	ret = pwrdm_for_each(pwrdms_setup, NULL);
505 	if (ret) {
506 		pr_err("Failed to setup powerdomains\n");
507 		goto err3;
508 	}
509 
510 	(void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
511 
512 	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
513 	if (mpu_pwrdm == NULL) {
514 		pr_err("Failed to get mpu_pwrdm\n");
515 		ret = -EINVAL;
516 		goto err3;
517 	}
518 
519 	neon_pwrdm = pwrdm_lookup("neon_pwrdm");
520 	per_pwrdm = pwrdm_lookup("per_pwrdm");
521 	core_pwrdm = pwrdm_lookup("core_pwrdm");
522 
523 	neon_clkdm = clkdm_lookup("neon_clkdm");
524 	mpu_clkdm = clkdm_lookup("mpu_clkdm");
525 	per_clkdm = clkdm_lookup("per_clkdm");
526 	wkup_clkdm = clkdm_lookup("wkup_clkdm");
527 
528 	omap_common_suspend_init(omap3_pm_suspend);
529 
530 	arm_pm_idle = omap3_pm_idle;
531 	omap3_idle_init();
532 
533 	/*
534 	 * RTA is disabled during initialization as per erratum i608
535 	 * it is safer to disable RTA by the bootloader, but we would like
536 	 * to be doubly sure here and prevent any mishaps.
537 	 */
538 	if (IS_PM34XX_ERRATUM(PM_RTA_ERRATUM_i608))
539 		omap3630_ctrl_disable_rta();
540 
541 	/*
542 	 * The UART3/4 FIFO and the sidetone memory in McBSP2/3 are
543 	 * not correctly reset when the PER powerdomain comes back
544 	 * from OFF or OSWR when the CORE powerdomain is kept active.
545 	 * See OMAP36xx Erratum i582 "PER Domain reset issue after
546 	 * Domain-OFF/OSWR Wakeup".  This wakeup dependency is not a
547 	 * complete workaround.  The kernel must also prevent the PER
548 	 * powerdomain from going to OSWR/OFF while the CORE
549 	 * powerdomain is not going to OSWR/OFF.  And if PER last
550 	 * power state was off while CORE last power state was ON, the
551 	 * UART3/4 and McBSP2/3 SIDETONE devices need to run a
552 	 * self-test using their loopback tests; if that fails, those
553 	 * devices are unusable until the PER/CORE can complete a transition
554 	 * from ON to OSWR/OFF and then back to ON.
555 	 *
556 	 * XXX Technically this workaround is only needed if off-mode
557 	 * or OSWR is enabled.
558 	 */
559 	if (IS_PM34XX_ERRATUM(PM_PER_MEMORIES_ERRATUM_i582))
560 		clkdm_add_wkdep(per_clkdm, wkup_clkdm);
561 
562 	clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
563 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
564 		omap3_secure_ram_storage =
565 			kmalloc(OMAP3_SAVE_SECURE_RAM_SZ, GFP_KERNEL);
566 		if (!omap3_secure_ram_storage)
567 			pr_err("Memory allocation failed when allocating for secure sram context\n");
568 
569 		local_irq_disable();
570 
571 		omap3_save_secure_ram_context();
572 
573 		local_irq_enable();
574 	}
575 
576 	omap3_save_scratchpad_contents();
577 	return ret;
578 
579 err3:
580 	list_for_each_entry_safe(pwrst, tmp, &pwrst_list, node) {
581 		list_del(&pwrst->node);
582 		kfree(pwrst);
583 	}
584 	free_irq(omap_prcm_event_to_irq("io"), omap3_pm_init);
585 err2:
586 	free_irq(omap_prcm_event_to_irq("wkup"), NULL);
587 err1:
588 	return ret;
589 }
590