xref: /openbmc/linux/arch/arm/mach-omap2/pm34xx.c (revision 3dc4b6fb)
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/omap-dma.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 	omap_dma_global_context_save();
89 }
90 
91 static void omap3_core_restore_context(void)
92 {
93 	/* Restore the control module context, padconf restored by h/w */
94 	omap3_control_restore_context();
95 	/* Restore the GPMC context */
96 	omap3_gpmc_restore_context();
97 	/* Restore the interrupt controller context */
98 	omap_intc_restore_context();
99 	omap_dma_global_context_restore();
100 }
101 
102 /*
103  * FIXME: This function should be called before entering off-mode after
104  * OMAP3 secure services have been accessed. Currently it is only called
105  * once during boot sequence, but this works as we are not using secure
106  * services.
107  */
108 static void omap3_save_secure_ram_context(void)
109 {
110 	u32 ret;
111 	int mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
112 
113 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
114 		/*
115 		 * MPU next state must be set to POWER_ON temporarily,
116 		 * otherwise the WFI executed inside the ROM code
117 		 * will hang the system.
118 		 */
119 		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
120 		ret = omap3_save_secure_ram(omap3_secure_ram_storage,
121 					    OMAP3_SAVE_SECURE_RAM_SZ);
122 		pwrdm_set_next_pwrst(mpu_pwrdm, mpu_next_state);
123 		/* Following is for error tracking, it should not happen */
124 		if (ret) {
125 			pr_err("save_secure_sram() returns %08x\n", ret);
126 			while (1)
127 				;
128 		}
129 	}
130 }
131 
132 static irqreturn_t _prcm_int_handle_io(int irq, void *unused)
133 {
134 	int c;
135 
136 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, OMAP3430_ST_IO_MASK |
137 				    OMAP3430_ST_IO_CHAIN_MASK);
138 
139 	return c ? IRQ_HANDLED : IRQ_NONE;
140 }
141 
142 static irqreturn_t _prcm_int_handle_wakeup(int irq, void *unused)
143 {
144 	int c;
145 
146 	/*
147 	 * Clear all except ST_IO and ST_IO_CHAIN for wkup module,
148 	 * these are handled in a separate handler to avoid acking
149 	 * IO events before parsing in mux code
150 	 */
151 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, ~(OMAP3430_ST_IO_MASK |
152 						   OMAP3430_ST_IO_CHAIN_MASK));
153 	c += omap_prm_clear_mod_irqs(CORE_MOD, 1, ~0);
154 	c += omap_prm_clear_mod_irqs(OMAP3430_PER_MOD, 1, ~0);
155 	if (omap_rev() > OMAP3430_REV_ES1_0) {
156 		c += omap_prm_clear_mod_irqs(CORE_MOD, 3, ~0);
157 		c += omap_prm_clear_mod_irqs(OMAP3430ES2_USBHOST_MOD, 1, ~0);
158 	}
159 
160 	return c ? IRQ_HANDLED : IRQ_NONE;
161 }
162 
163 static void omap34xx_save_context(u32 *save)
164 {
165 	u32 val;
166 
167 	/* Read Auxiliary Control Register */
168 	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (val));
169 	*save++ = 1;
170 	*save++ = val;
171 
172 	/* Read L2 AUX ctrl register */
173 	asm("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
174 	*save++ = 1;
175 	*save++ = val;
176 }
177 
178 static int omap34xx_do_sram_idle(unsigned long save_state)
179 {
180 	omap34xx_cpu_suspend(save_state);
181 	return 0;
182 }
183 
184 void omap_sram_idle(void)
185 {
186 	/* Variable to tell what needs to be saved and restored
187 	 * in omap_sram_idle*/
188 	/* save_state = 0 => Nothing to save and restored */
189 	/* save_state = 1 => Only L1 and logic lost */
190 	/* save_state = 2 => Only L2 lost */
191 	/* save_state = 3 => L1, L2 and logic lost */
192 	int save_state = 0;
193 	int mpu_next_state = PWRDM_POWER_ON;
194 	int per_next_state = PWRDM_POWER_ON;
195 	int core_next_state = PWRDM_POWER_ON;
196 	u32 sdrc_pwr = 0;
197 
198 	mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
199 	switch (mpu_next_state) {
200 	case PWRDM_POWER_ON:
201 	case PWRDM_POWER_RET:
202 		/* No need to save context */
203 		save_state = 0;
204 		break;
205 	case PWRDM_POWER_OFF:
206 		save_state = 3;
207 		break;
208 	default:
209 		/* Invalid state */
210 		pr_err("Invalid mpu state in sram_idle\n");
211 		return;
212 	}
213 
214 	/* NEON control */
215 	if (pwrdm_read_pwrst(neon_pwrdm) == PWRDM_POWER_ON)
216 		pwrdm_set_next_pwrst(neon_pwrdm, mpu_next_state);
217 
218 	/* Enable IO-PAD and IO-CHAIN wakeups */
219 	per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
220 	core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
221 
222 	pwrdm_pre_transition(NULL);
223 
224 	/* PER */
225 	if (per_next_state == PWRDM_POWER_OFF)
226 		cpu_cluster_pm_enter();
227 
228 	/* CORE */
229 	if (core_next_state < PWRDM_POWER_ON) {
230 		if (core_next_state == PWRDM_POWER_OFF) {
231 			omap3_core_save_context();
232 			omap3_cm_save_context();
233 		}
234 	}
235 
236 	/* Configure PMIC signaling for I2C4 or sys_off_mode */
237 	omap3_vc_set_pmic_signaling(core_next_state);
238 
239 	omap3_intc_prepare_idle();
240 
241 	/*
242 	 * On EMU/HS devices ROM code restores a SRDC value
243 	 * from scratchpad which has automatic self refresh on timeout
244 	 * of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
245 	 * Hence store/restore the SDRC_POWER register here.
246 	 */
247 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
248 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
249 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
250 	    core_next_state == PWRDM_POWER_OFF)
251 		sdrc_pwr = sdrc_read_reg(SDRC_POWER);
252 
253 	/*
254 	 * omap3_arm_context is the location where some ARM context
255 	 * get saved. The rest is placed on the stack, and restored
256 	 * from there before resuming.
257 	 */
258 	if (save_state)
259 		omap34xx_save_context(omap3_arm_context);
260 	if (save_state == 1 || save_state == 3)
261 		cpu_suspend(save_state, omap34xx_do_sram_idle);
262 	else
263 		omap34xx_do_sram_idle(save_state);
264 
265 	/* Restore normal SDRC POWER settings */
266 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
267 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
268 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
269 	    core_next_state == PWRDM_POWER_OFF)
270 		sdrc_write_reg(sdrc_pwr, SDRC_POWER);
271 
272 	/* CORE */
273 	if (core_next_state < PWRDM_POWER_ON &&
274 	    pwrdm_read_prev_pwrst(core_pwrdm) == PWRDM_POWER_OFF) {
275 		omap3_core_restore_context();
276 		omap3_cm_restore_context();
277 		omap3_sram_restore_context();
278 		omap2_sms_restore_context();
279 	} else {
280 		/*
281 		 * In off-mode resume path above, omap3_core_restore_context
282 		 * also handles the INTC autoidle restore done here so limit
283 		 * this to non-off mode resume paths so we don't do it twice.
284 		 */
285 		omap3_intc_resume_idle();
286 	}
287 
288 	pwrdm_post_transition(NULL);
289 
290 	/* PER */
291 	if (per_next_state == PWRDM_POWER_OFF)
292 		cpu_cluster_pm_exit();
293 }
294 
295 static void omap3_pm_idle(void)
296 {
297 	if (omap_irq_pending())
298 		return;
299 
300 	trace_cpu_idle_rcuidle(1, smp_processor_id());
301 
302 	omap_sram_idle();
303 
304 	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
305 }
306 
307 #ifdef CONFIG_SUSPEND
308 static int omap3_pm_suspend(void)
309 {
310 	struct power_state *pwrst;
311 	int state, ret = 0;
312 
313 	/* Read current next_pwrsts */
314 	list_for_each_entry(pwrst, &pwrst_list, node)
315 		pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
316 	/* Set ones wanted by suspend */
317 	list_for_each_entry(pwrst, &pwrst_list, node) {
318 		if (omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state))
319 			goto restore;
320 		if (pwrdm_clear_all_prev_pwrst(pwrst->pwrdm))
321 			goto restore;
322 	}
323 
324 	omap3_intc_suspend();
325 
326 	omap_sram_idle();
327 
328 restore:
329 	/* Restore next_pwrsts */
330 	list_for_each_entry(pwrst, &pwrst_list, node) {
331 		state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
332 		if (state > pwrst->next_state) {
333 			pr_info("Powerdomain (%s) didn't enter target state %d\n",
334 				pwrst->pwrdm->name, pwrst->next_state);
335 			ret = -1;
336 		}
337 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
338 	}
339 	if (ret)
340 		pr_err("Could not enter target state in pm_suspend\n");
341 	else
342 		pr_info("Successfully put all powerdomains to target state\n");
343 
344 	return ret;
345 }
346 #else
347 #define omap3_pm_suspend NULL
348 #endif /* CONFIG_SUSPEND */
349 
350 static void __init prcm_setup_regs(void)
351 {
352 	omap3_ctrl_init();
353 
354 	omap3_prm_init_pm(cpu_is_omap3630(), omap3_has_iva());
355 }
356 
357 void omap3_pm_off_mode_enable(int enable)
358 {
359 	struct power_state *pwrst;
360 	u32 state;
361 
362 	if (enable)
363 		state = PWRDM_POWER_OFF;
364 	else
365 		state = PWRDM_POWER_RET;
366 
367 	list_for_each_entry(pwrst, &pwrst_list, node) {
368 		if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) &&
369 				pwrst->pwrdm == core_pwrdm &&
370 				state == PWRDM_POWER_OFF) {
371 			pwrst->next_state = PWRDM_POWER_RET;
372 			pr_warn("%s: Core OFF disabled due to errata i583\n",
373 				__func__);
374 		} else {
375 			pwrst->next_state = state;
376 		}
377 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
378 	}
379 }
380 
381 int omap3_pm_get_suspend_state(struct powerdomain *pwrdm)
382 {
383 	struct power_state *pwrst;
384 
385 	list_for_each_entry(pwrst, &pwrst_list, node) {
386 		if (pwrst->pwrdm == pwrdm)
387 			return pwrst->next_state;
388 	}
389 	return -EINVAL;
390 }
391 
392 int omap3_pm_set_suspend_state(struct powerdomain *pwrdm, int state)
393 {
394 	struct power_state *pwrst;
395 
396 	list_for_each_entry(pwrst, &pwrst_list, node) {
397 		if (pwrst->pwrdm == pwrdm) {
398 			pwrst->next_state = state;
399 			return 0;
400 		}
401 	}
402 	return -EINVAL;
403 }
404 
405 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
406 {
407 	struct power_state *pwrst;
408 
409 	if (!pwrdm->pwrsts)
410 		return 0;
411 
412 	pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
413 	if (!pwrst)
414 		return -ENOMEM;
415 	pwrst->pwrdm = pwrdm;
416 	pwrst->next_state = PWRDM_POWER_RET;
417 	list_add(&pwrst->node, &pwrst_list);
418 
419 	if (pwrdm_has_hdwr_sar(pwrdm))
420 		pwrdm_enable_hdwr_sar(pwrdm);
421 
422 	return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
423 }
424 
425 /*
426  * Push functions to SRAM
427  *
428  * The minimum set of functions is pushed to SRAM for execution:
429  * - omap3_do_wfi for erratum i581 WA,
430  */
431 void omap_push_sram_idle(void)
432 {
433 	omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
434 }
435 
436 static void __init pm_errata_configure(void)
437 {
438 	if (cpu_is_omap3630()) {
439 		pm34xx_errata |= PM_RTA_ERRATUM_i608;
440 		/* Enable the l2 cache toggling in sleep logic */
441 		enable_omap3630_toggle_l2_on_restore();
442 		if (omap_rev() < OMAP3630_REV_ES1_2)
443 			pm34xx_errata |= (PM_SDRC_WAKEUP_ERRATUM_i583 |
444 					  PM_PER_MEMORIES_ERRATUM_i582);
445 	} else if (cpu_is_omap34xx()) {
446 		pm34xx_errata |= PM_PER_MEMORIES_ERRATUM_i582;
447 	}
448 }
449 
450 int __init omap3_pm_init(void)
451 {
452 	struct power_state *pwrst, *tmp;
453 	struct clockdomain *neon_clkdm, *mpu_clkdm, *per_clkdm, *wkup_clkdm;
454 	int ret;
455 
456 	if (!omap3_has_io_chain_ctrl())
457 		pr_warn("PM: no software I/O chain control; some wakeups may be lost\n");
458 
459 	pm_errata_configure();
460 
461 	/* XXX prcm_setup_regs needs to be before enabling hw
462 	 * supervised mode for powerdomains */
463 	prcm_setup_regs();
464 
465 	ret = request_irq(omap_prcm_event_to_irq("wkup"),
466 		_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
467 
468 	if (ret) {
469 		pr_err("pm: Failed to request pm_wkup irq\n");
470 		goto err1;
471 	}
472 
473 	/* IO interrupt is shared with mux code */
474 	ret = request_irq(omap_prcm_event_to_irq("io"),
475 		_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
476 		omap3_pm_init);
477 
478 	if (ret) {
479 		pr_err("pm: Failed to request pm_io irq\n");
480 		goto err2;
481 	}
482 
483 	ret = pwrdm_for_each(pwrdms_setup, NULL);
484 	if (ret) {
485 		pr_err("Failed to setup powerdomains\n");
486 		goto err3;
487 	}
488 
489 	(void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
490 
491 	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
492 	if (mpu_pwrdm == NULL) {
493 		pr_err("Failed to get mpu_pwrdm\n");
494 		ret = -EINVAL;
495 		goto err3;
496 	}
497 
498 	neon_pwrdm = pwrdm_lookup("neon_pwrdm");
499 	per_pwrdm = pwrdm_lookup("per_pwrdm");
500 	core_pwrdm = pwrdm_lookup("core_pwrdm");
501 
502 	neon_clkdm = clkdm_lookup("neon_clkdm");
503 	mpu_clkdm = clkdm_lookup("mpu_clkdm");
504 	per_clkdm = clkdm_lookup("per_clkdm");
505 	wkup_clkdm = clkdm_lookup("wkup_clkdm");
506 
507 	omap_common_suspend_init(omap3_pm_suspend);
508 
509 	arm_pm_idle = omap3_pm_idle;
510 	omap3_idle_init();
511 
512 	/*
513 	 * RTA is disabled during initialization as per erratum i608
514 	 * it is safer to disable RTA by the bootloader, but we would like
515 	 * to be doubly sure here and prevent any mishaps.
516 	 */
517 	if (IS_PM34XX_ERRATUM(PM_RTA_ERRATUM_i608))
518 		omap3630_ctrl_disable_rta();
519 
520 	/*
521 	 * The UART3/4 FIFO and the sidetone memory in McBSP2/3 are
522 	 * not correctly reset when the PER powerdomain comes back
523 	 * from OFF or OSWR when the CORE powerdomain is kept active.
524 	 * See OMAP36xx Erratum i582 "PER Domain reset issue after
525 	 * Domain-OFF/OSWR Wakeup".  This wakeup dependency is not a
526 	 * complete workaround.  The kernel must also prevent the PER
527 	 * powerdomain from going to OSWR/OFF while the CORE
528 	 * powerdomain is not going to OSWR/OFF.  And if PER last
529 	 * power state was off while CORE last power state was ON, the
530 	 * UART3/4 and McBSP2/3 SIDETONE devices need to run a
531 	 * self-test using their loopback tests; if that fails, those
532 	 * devices are unusable until the PER/CORE can complete a transition
533 	 * from ON to OSWR/OFF and then back to ON.
534 	 *
535 	 * XXX Technically this workaround is only needed if off-mode
536 	 * or OSWR is enabled.
537 	 */
538 	if (IS_PM34XX_ERRATUM(PM_PER_MEMORIES_ERRATUM_i582))
539 		clkdm_add_wkdep(per_clkdm, wkup_clkdm);
540 
541 	clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
542 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
543 		omap3_secure_ram_storage =
544 			kmalloc(OMAP3_SAVE_SECURE_RAM_SZ, GFP_KERNEL);
545 		if (!omap3_secure_ram_storage)
546 			pr_err("Memory allocation failed when allocating for secure sram context\n");
547 
548 		local_irq_disable();
549 
550 		omap_dma_global_context_save();
551 		omap3_save_secure_ram_context();
552 		omap_dma_global_context_restore();
553 
554 		local_irq_enable();
555 	}
556 
557 	omap3_save_scratchpad_contents();
558 	return ret;
559 
560 err3:
561 	list_for_each_entry_safe(pwrst, tmp, &pwrst_list, node) {
562 		list_del(&pwrst->node);
563 		kfree(pwrst);
564 	}
565 	free_irq(omap_prcm_event_to_irq("io"), omap3_pm_init);
566 err2:
567 	free_irq(omap_prcm_event_to_irq("wkup"), NULL);
568 err1:
569 	return ret;
570 }
571