xref: /openbmc/linux/arch/arm/mach-omap2/pm34xx.c (revision 63705da3)
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 
30 #include <trace/events/power.h>
31 
32 #include <asm/fncpy.h>
33 #include <asm/suspend.h>
34 #include <asm/system_misc.h>
35 
36 #include "clockdomain.h"
37 #include "powerdomain.h"
38 #include "soc.h"
39 #include "common.h"
40 #include "cm3xxx.h"
41 #include "cm-regbits-34xx.h"
42 #include "prm-regbits-34xx.h"
43 #include "prm3xxx.h"
44 #include "pm.h"
45 #include "sdrc.h"
46 #include "omap-secure.h"
47 #include "sram.h"
48 #include "control.h"
49 #include "vc.h"
50 
51 /* pm34xx errata defined in pm.h */
52 u16 pm34xx_errata;
53 
54 struct power_state {
55 	struct powerdomain *pwrdm;
56 	u32 next_state;
57 #ifdef CONFIG_SUSPEND
58 	u32 saved_state;
59 #endif
60 	struct list_head node;
61 };
62 
63 static LIST_HEAD(pwrst_list);
64 
65 void (*omap3_do_wfi_sram)(void);
66 
67 static struct powerdomain *mpu_pwrdm, *neon_pwrdm;
68 static struct powerdomain *core_pwrdm, *per_pwrdm;
69 
70 static void omap3_core_save_context(void)
71 {
72 	omap3_ctrl_save_padconf();
73 
74 	/*
75 	 * Force write last pad into memory, as this can fail in some
76 	 * cases according to errata 1.157, 1.185
77 	 */
78 	omap_ctrl_writel(omap_ctrl_readl(OMAP343X_PADCONF_ETK_D14),
79 		OMAP343X_CONTROL_MEM_WKUP + 0x2a0);
80 
81 	/* Save the Interrupt controller context */
82 	omap_intc_save_context();
83 	/* Save the system control module context, padconf already save above*/
84 	omap3_control_save_context();
85 }
86 
87 static void omap3_core_restore_context(void)
88 {
89 	/* Restore the control module context, padconf restored by h/w */
90 	omap3_control_restore_context();
91 	/* Restore the interrupt controller context */
92 	omap_intc_restore_context();
93 }
94 
95 /*
96  * FIXME: This function should be called before entering off-mode after
97  * OMAP3 secure services have been accessed. Currently it is only called
98  * once during boot sequence, but this works as we are not using secure
99  * services.
100  */
101 static void omap3_save_secure_ram_context(void)
102 {
103 	u32 ret;
104 	int mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
105 
106 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
107 		/*
108 		 * MPU next state must be set to POWER_ON temporarily,
109 		 * otherwise the WFI executed inside the ROM code
110 		 * will hang the system.
111 		 */
112 		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
113 		ret = omap3_save_secure_ram(omap3_secure_ram_storage,
114 					    OMAP3_SAVE_SECURE_RAM_SZ);
115 		pwrdm_set_next_pwrst(mpu_pwrdm, mpu_next_state);
116 		/* Following is for error tracking, it should not happen */
117 		if (ret) {
118 			pr_err("save_secure_sram() returns %08x\n", ret);
119 			while (1)
120 				;
121 		}
122 	}
123 }
124 
125 static irqreturn_t _prcm_int_handle_io(int irq, void *unused)
126 {
127 	int c;
128 
129 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, OMAP3430_ST_IO_MASK |
130 				    OMAP3430_ST_IO_CHAIN_MASK);
131 
132 	return c ? IRQ_HANDLED : IRQ_NONE;
133 }
134 
135 static irqreturn_t _prcm_int_handle_wakeup(int irq, void *unused)
136 {
137 	int c;
138 
139 	/*
140 	 * Clear all except ST_IO and ST_IO_CHAIN for wkup module,
141 	 * these are handled in a separate handler to avoid acking
142 	 * IO events before parsing in mux code
143 	 */
144 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, ~(OMAP3430_ST_IO_MASK |
145 						   OMAP3430_ST_IO_CHAIN_MASK));
146 	c += omap_prm_clear_mod_irqs(CORE_MOD, 1, ~0);
147 	c += omap_prm_clear_mod_irqs(OMAP3430_PER_MOD, 1, ~0);
148 	if (omap_rev() > OMAP3430_REV_ES1_0) {
149 		c += omap_prm_clear_mod_irqs(CORE_MOD, 3, ~0);
150 		c += omap_prm_clear_mod_irqs(OMAP3430ES2_USBHOST_MOD, 1, ~0);
151 	}
152 
153 	return c ? IRQ_HANDLED : IRQ_NONE;
154 }
155 
156 static void omap34xx_save_context(u32 *save)
157 {
158 	u32 val;
159 
160 	/* Read Auxiliary Control Register */
161 	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (val));
162 	*save++ = 1;
163 	*save++ = val;
164 
165 	/* Read L2 AUX ctrl register */
166 	asm("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
167 	*save++ = 1;
168 	*save++ = val;
169 }
170 
171 static int omap34xx_do_sram_idle(unsigned long save_state)
172 {
173 	omap34xx_cpu_suspend(save_state);
174 	return 0;
175 }
176 
177 void omap_sram_idle(void)
178 {
179 	/* Variable to tell what needs to be saved and restored
180 	 * in omap_sram_idle*/
181 	/* save_state = 0 => Nothing to save and restored */
182 	/* save_state = 1 => Only L1 and logic lost */
183 	/* save_state = 2 => Only L2 lost */
184 	/* save_state = 3 => L1, L2 and logic lost */
185 	int save_state = 0;
186 	int mpu_next_state = PWRDM_POWER_ON;
187 	int per_next_state = PWRDM_POWER_ON;
188 	int core_next_state = PWRDM_POWER_ON;
189 	u32 sdrc_pwr = 0;
190 	int error;
191 
192 	mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
193 	switch (mpu_next_state) {
194 	case PWRDM_POWER_ON:
195 	case PWRDM_POWER_RET:
196 		/* No need to save context */
197 		save_state = 0;
198 		break;
199 	case PWRDM_POWER_OFF:
200 		save_state = 3;
201 		break;
202 	default:
203 		/* Invalid state */
204 		pr_err("Invalid mpu state in sram_idle\n");
205 		return;
206 	}
207 
208 	/* NEON control */
209 	if (pwrdm_read_pwrst(neon_pwrdm) == PWRDM_POWER_ON)
210 		pwrdm_set_next_pwrst(neon_pwrdm, mpu_next_state);
211 
212 	/* Enable IO-PAD and IO-CHAIN wakeups */
213 	per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
214 	core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
215 
216 	pwrdm_pre_transition(NULL);
217 
218 	/* PER */
219 	if (per_next_state == PWRDM_POWER_OFF) {
220 		error = cpu_cluster_pm_enter();
221 		if (error)
222 			return;
223 	}
224 
225 	/* CORE */
226 	if (core_next_state < PWRDM_POWER_ON) {
227 		if (core_next_state == PWRDM_POWER_OFF) {
228 			omap3_core_save_context();
229 			omap3_cm_save_context();
230 		}
231 	}
232 
233 	/* Configure PMIC signaling for I2C4 or sys_off_mode */
234 	omap3_vc_set_pmic_signaling(core_next_state);
235 
236 	omap3_intc_prepare_idle();
237 
238 	/*
239 	 * On EMU/HS devices ROM code restores a SRDC value
240 	 * from scratchpad which has automatic self refresh on timeout
241 	 * of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
242 	 * Hence store/restore the SDRC_POWER register here.
243 	 */
244 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
245 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
246 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
247 	    core_next_state == PWRDM_POWER_OFF)
248 		sdrc_pwr = sdrc_read_reg(SDRC_POWER);
249 
250 	/*
251 	 * omap3_arm_context is the location where some ARM context
252 	 * get saved. The rest is placed on the stack, and restored
253 	 * from there before resuming.
254 	 */
255 	if (save_state)
256 		omap34xx_save_context(omap3_arm_context);
257 	if (save_state == 1 || save_state == 3)
258 		cpu_suspend(save_state, omap34xx_do_sram_idle);
259 	else
260 		omap34xx_do_sram_idle(save_state);
261 
262 	/* Restore normal SDRC POWER settings */
263 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
264 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
265 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
266 	    core_next_state == PWRDM_POWER_OFF)
267 		sdrc_write_reg(sdrc_pwr, SDRC_POWER);
268 
269 	/* CORE */
270 	if (core_next_state < PWRDM_POWER_ON &&
271 	    pwrdm_read_prev_pwrst(core_pwrdm) == PWRDM_POWER_OFF) {
272 		omap3_core_restore_context();
273 		omap3_cm_restore_context();
274 		omap3_sram_restore_context();
275 		omap2_sms_restore_context();
276 	} else {
277 		/*
278 		 * In off-mode resume path above, omap3_core_restore_context
279 		 * also handles the INTC autoidle restore done here so limit
280 		 * this to non-off mode resume paths so we don't do it twice.
281 		 */
282 		omap3_intc_resume_idle();
283 	}
284 
285 	pwrdm_post_transition(NULL);
286 
287 	/* PER */
288 	if (per_next_state == PWRDM_POWER_OFF)
289 		cpu_cluster_pm_exit();
290 }
291 
292 static void omap3_pm_idle(void)
293 {
294 	if (omap_irq_pending())
295 		return;
296 
297 	omap_sram_idle();
298 }
299 
300 #ifdef CONFIG_SUSPEND
301 static int omap3_pm_suspend(void)
302 {
303 	struct power_state *pwrst;
304 	int state, ret = 0;
305 
306 	/* Read current next_pwrsts */
307 	list_for_each_entry(pwrst, &pwrst_list, node)
308 		pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
309 	/* Set ones wanted by suspend */
310 	list_for_each_entry(pwrst, &pwrst_list, node) {
311 		if (omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state))
312 			goto restore;
313 		if (pwrdm_clear_all_prev_pwrst(pwrst->pwrdm))
314 			goto restore;
315 	}
316 
317 	omap3_intc_suspend();
318 
319 	omap_sram_idle();
320 
321 restore:
322 	/* Restore next_pwrsts */
323 	list_for_each_entry(pwrst, &pwrst_list, node) {
324 		state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
325 		if (state > pwrst->next_state) {
326 			pr_info("Powerdomain (%s) didn't enter target state %d\n",
327 				pwrst->pwrdm->name, pwrst->next_state);
328 			ret = -1;
329 		}
330 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
331 	}
332 	if (ret)
333 		pr_err("Could not enter target state in pm_suspend\n");
334 	else
335 		pr_info("Successfully put all powerdomains to target state\n");
336 
337 	return ret;
338 }
339 #else
340 #define omap3_pm_suspend NULL
341 #endif /* CONFIG_SUSPEND */
342 
343 static void __init prcm_setup_regs(void)
344 {
345 	omap3_ctrl_init();
346 
347 	omap3_prm_init_pm(cpu_is_omap3630(), omap3_has_iva());
348 }
349 
350 void omap3_pm_off_mode_enable(int enable)
351 {
352 	struct power_state *pwrst;
353 	u32 state;
354 
355 	if (enable)
356 		state = PWRDM_POWER_OFF;
357 	else
358 		state = PWRDM_POWER_RET;
359 
360 	list_for_each_entry(pwrst, &pwrst_list, node) {
361 		if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) &&
362 				pwrst->pwrdm == core_pwrdm &&
363 				state == PWRDM_POWER_OFF) {
364 			pwrst->next_state = PWRDM_POWER_RET;
365 			pr_warn("%s: Core OFF disabled due to errata i583\n",
366 				__func__);
367 		} else {
368 			pwrst->next_state = state;
369 		}
370 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
371 	}
372 }
373 
374 int omap3_pm_get_suspend_state(struct powerdomain *pwrdm)
375 {
376 	struct power_state *pwrst;
377 
378 	list_for_each_entry(pwrst, &pwrst_list, node) {
379 		if (pwrst->pwrdm == pwrdm)
380 			return pwrst->next_state;
381 	}
382 	return -EINVAL;
383 }
384 
385 int omap3_pm_set_suspend_state(struct powerdomain *pwrdm, int state)
386 {
387 	struct power_state *pwrst;
388 
389 	list_for_each_entry(pwrst, &pwrst_list, node) {
390 		if (pwrst->pwrdm == pwrdm) {
391 			pwrst->next_state = state;
392 			return 0;
393 		}
394 	}
395 	return -EINVAL;
396 }
397 
398 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
399 {
400 	struct power_state *pwrst;
401 
402 	if (!pwrdm->pwrsts)
403 		return 0;
404 
405 	pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
406 	if (!pwrst)
407 		return -ENOMEM;
408 	pwrst->pwrdm = pwrdm;
409 
410 	if (enable_off_mode)
411 		pwrst->next_state = PWRDM_POWER_OFF;
412 	else
413 		pwrst->next_state = PWRDM_POWER_RET;
414 
415 	list_add(&pwrst->node, &pwrst_list);
416 
417 	if (pwrdm_has_hdwr_sar(pwrdm))
418 		pwrdm_enable_hdwr_sar(pwrdm);
419 
420 	return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
421 }
422 
423 /*
424  * Push functions to SRAM
425  *
426  * The minimum set of functions is pushed to SRAM for execution:
427  * - omap3_do_wfi for erratum i581 WA,
428  */
429 void omap_push_sram_idle(void)
430 {
431 	omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
432 }
433 
434 static void __init pm_errata_configure(void)
435 {
436 	if (cpu_is_omap3630()) {
437 		pm34xx_errata |= PM_RTA_ERRATUM_i608;
438 		/* Enable the l2 cache toggling in sleep logic */
439 		enable_omap3630_toggle_l2_on_restore();
440 		if (omap_rev() < OMAP3630_REV_ES1_2)
441 			pm34xx_errata |= (PM_SDRC_WAKEUP_ERRATUM_i583 |
442 					  PM_PER_MEMORIES_ERRATUM_i582);
443 	} else if (cpu_is_omap34xx()) {
444 		pm34xx_errata |= PM_PER_MEMORIES_ERRATUM_i582;
445 	}
446 }
447 
448 static void __init omap3_pm_check_pmic(void)
449 {
450 	struct device_node *np;
451 
452 	np = of_find_compatible_node(NULL, NULL, "ti,twl4030-power-idle");
453 	if (!np)
454 		np = of_find_compatible_node(NULL, NULL, "ti,twl4030-power-idle-osc-off");
455 
456 	if (np) {
457 		of_node_put(np);
458 		enable_off_mode = 1;
459 	} else {
460 		enable_off_mode = 0;
461 	}
462 }
463 
464 int __init omap3_pm_init(void)
465 {
466 	struct power_state *pwrst, *tmp;
467 	struct clockdomain *neon_clkdm, *mpu_clkdm, *per_clkdm, *wkup_clkdm;
468 	int ret;
469 
470 	if (!omap3_has_io_chain_ctrl())
471 		pr_warn("PM: no software I/O chain control; some wakeups may be lost\n");
472 
473 	pm_errata_configure();
474 
475 	/* XXX prcm_setup_regs needs to be before enabling hw
476 	 * supervised mode for powerdomains */
477 	prcm_setup_regs();
478 
479 	ret = request_irq(omap_prcm_event_to_irq("wkup"),
480 		_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
481 
482 	if (ret) {
483 		pr_err("pm: Failed to request pm_wkup irq\n");
484 		goto err1;
485 	}
486 
487 	/* IO interrupt is shared with mux code */
488 	ret = request_irq(omap_prcm_event_to_irq("io"),
489 		_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
490 		omap3_pm_init);
491 
492 	if (ret) {
493 		pr_err("pm: Failed to request pm_io irq\n");
494 		goto err2;
495 	}
496 
497 	omap3_pm_check_pmic();
498 
499 	ret = pwrdm_for_each(pwrdms_setup, NULL);
500 	if (ret) {
501 		pr_err("Failed to setup powerdomains\n");
502 		goto err3;
503 	}
504 
505 	(void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
506 
507 	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
508 	if (mpu_pwrdm == NULL) {
509 		pr_err("Failed to get mpu_pwrdm\n");
510 		ret = -EINVAL;
511 		goto err3;
512 	}
513 
514 	neon_pwrdm = pwrdm_lookup("neon_pwrdm");
515 	per_pwrdm = pwrdm_lookup("per_pwrdm");
516 	core_pwrdm = pwrdm_lookup("core_pwrdm");
517 
518 	neon_clkdm = clkdm_lookup("neon_clkdm");
519 	mpu_clkdm = clkdm_lookup("mpu_clkdm");
520 	per_clkdm = clkdm_lookup("per_clkdm");
521 	wkup_clkdm = clkdm_lookup("wkup_clkdm");
522 
523 	omap_common_suspend_init(omap3_pm_suspend);
524 
525 	arm_pm_idle = omap3_pm_idle;
526 	omap3_idle_init();
527 
528 	/*
529 	 * RTA is disabled during initialization as per erratum i608
530 	 * it is safer to disable RTA by the bootloader, but we would like
531 	 * to be doubly sure here and prevent any mishaps.
532 	 */
533 	if (IS_PM34XX_ERRATUM(PM_RTA_ERRATUM_i608))
534 		omap3630_ctrl_disable_rta();
535 
536 	/*
537 	 * The UART3/4 FIFO and the sidetone memory in McBSP2/3 are
538 	 * not correctly reset when the PER powerdomain comes back
539 	 * from OFF or OSWR when the CORE powerdomain is kept active.
540 	 * See OMAP36xx Erratum i582 "PER Domain reset issue after
541 	 * Domain-OFF/OSWR Wakeup".  This wakeup dependency is not a
542 	 * complete workaround.  The kernel must also prevent the PER
543 	 * powerdomain from going to OSWR/OFF while the CORE
544 	 * powerdomain is not going to OSWR/OFF.  And if PER last
545 	 * power state was off while CORE last power state was ON, the
546 	 * UART3/4 and McBSP2/3 SIDETONE devices need to run a
547 	 * self-test using their loopback tests; if that fails, those
548 	 * devices are unusable until the PER/CORE can complete a transition
549 	 * from ON to OSWR/OFF and then back to ON.
550 	 *
551 	 * XXX Technically this workaround is only needed if off-mode
552 	 * or OSWR is enabled.
553 	 */
554 	if (IS_PM34XX_ERRATUM(PM_PER_MEMORIES_ERRATUM_i582))
555 		clkdm_add_wkdep(per_clkdm, wkup_clkdm);
556 
557 	clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
558 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
559 		omap3_secure_ram_storage =
560 			kmalloc(OMAP3_SAVE_SECURE_RAM_SZ, GFP_KERNEL);
561 		if (!omap3_secure_ram_storage)
562 			pr_err("Memory allocation failed when allocating for secure sram context\n");
563 
564 		local_irq_disable();
565 
566 		omap3_save_secure_ram_context();
567 
568 		local_irq_enable();
569 	}
570 
571 	omap3_save_scratchpad_contents();
572 	return ret;
573 
574 err3:
575 	list_for_each_entry_safe(pwrst, tmp, &pwrst_list, node) {
576 		list_del(&pwrst->node);
577 		kfree(pwrst);
578 	}
579 	free_irq(omap_prcm_event_to_irq("io"), omap3_pm_init);
580 err2:
581 	free_irq(omap_prcm_event_to_irq("wkup"), NULL);
582 err1:
583 	return ret;
584 }
585