xref: /openbmc/linux/arch/arm/mach-omap2/pm34xx.c (revision 297e77e5)
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-gpmc.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 GPMC context */
84 	omap3_gpmc_save_context();
85 	/* Save the system control module context, padconf already save above*/
86 	omap3_control_save_context();
87 }
88 
89 static void omap3_core_restore_context(void)
90 {
91 	/* Restore the control module context, padconf restored by h/w */
92 	omap3_control_restore_context();
93 	/* Restore the GPMC context */
94 	omap3_gpmc_restore_context();
95 	/* Restore the interrupt controller context */
96 	omap_intc_restore_context();
97 }
98 
99 /*
100  * FIXME: This function should be called before entering off-mode after
101  * OMAP3 secure services have been accessed. Currently it is only called
102  * once during boot sequence, but this works as we are not using secure
103  * services.
104  */
105 static void omap3_save_secure_ram_context(void)
106 {
107 	u32 ret;
108 	int mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
109 
110 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
111 		/*
112 		 * MPU next state must be set to POWER_ON temporarily,
113 		 * otherwise the WFI executed inside the ROM code
114 		 * will hang the system.
115 		 */
116 		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
117 		ret = omap3_save_secure_ram(omap3_secure_ram_storage,
118 					    OMAP3_SAVE_SECURE_RAM_SZ);
119 		pwrdm_set_next_pwrst(mpu_pwrdm, mpu_next_state);
120 		/* Following is for error tracking, it should not happen */
121 		if (ret) {
122 			pr_err("save_secure_sram() returns %08x\n", ret);
123 			while (1)
124 				;
125 		}
126 	}
127 }
128 
129 static irqreturn_t _prcm_int_handle_io(int irq, void *unused)
130 {
131 	int c;
132 
133 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, OMAP3430_ST_IO_MASK |
134 				    OMAP3430_ST_IO_CHAIN_MASK);
135 
136 	return c ? IRQ_HANDLED : IRQ_NONE;
137 }
138 
139 static irqreturn_t _prcm_int_handle_wakeup(int irq, void *unused)
140 {
141 	int c;
142 
143 	/*
144 	 * Clear all except ST_IO and ST_IO_CHAIN for wkup module,
145 	 * these are handled in a separate handler to avoid acking
146 	 * IO events before parsing in mux code
147 	 */
148 	c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, ~(OMAP3430_ST_IO_MASK |
149 						   OMAP3430_ST_IO_CHAIN_MASK));
150 	c += omap_prm_clear_mod_irqs(CORE_MOD, 1, ~0);
151 	c += omap_prm_clear_mod_irqs(OMAP3430_PER_MOD, 1, ~0);
152 	if (omap_rev() > OMAP3430_REV_ES1_0) {
153 		c += omap_prm_clear_mod_irqs(CORE_MOD, 3, ~0);
154 		c += omap_prm_clear_mod_irqs(OMAP3430ES2_USBHOST_MOD, 1, ~0);
155 	}
156 
157 	return c ? IRQ_HANDLED : IRQ_NONE;
158 }
159 
160 static void omap34xx_save_context(u32 *save)
161 {
162 	u32 val;
163 
164 	/* Read Auxiliary Control Register */
165 	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (val));
166 	*save++ = 1;
167 	*save++ = val;
168 
169 	/* Read L2 AUX ctrl register */
170 	asm("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
171 	*save++ = 1;
172 	*save++ = val;
173 }
174 
175 static int omap34xx_do_sram_idle(unsigned long save_state)
176 {
177 	omap34xx_cpu_suspend(save_state);
178 	return 0;
179 }
180 
181 void omap_sram_idle(void)
182 {
183 	/* Variable to tell what needs to be saved and restored
184 	 * in omap_sram_idle*/
185 	/* save_state = 0 => Nothing to save and restored */
186 	/* save_state = 1 => Only L1 and logic lost */
187 	/* save_state = 2 => Only L2 lost */
188 	/* save_state = 3 => L1, L2 and logic lost */
189 	int save_state = 0;
190 	int mpu_next_state = PWRDM_POWER_ON;
191 	int per_next_state = PWRDM_POWER_ON;
192 	int core_next_state = PWRDM_POWER_ON;
193 	u32 sdrc_pwr = 0;
194 	int error;
195 
196 	mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
197 	switch (mpu_next_state) {
198 	case PWRDM_POWER_ON:
199 	case PWRDM_POWER_RET:
200 		/* No need to save context */
201 		save_state = 0;
202 		break;
203 	case PWRDM_POWER_OFF:
204 		save_state = 3;
205 		break;
206 	default:
207 		/* Invalid state */
208 		pr_err("Invalid mpu state in sram_idle\n");
209 		return;
210 	}
211 
212 	/* NEON control */
213 	if (pwrdm_read_pwrst(neon_pwrdm) == PWRDM_POWER_ON)
214 		pwrdm_set_next_pwrst(neon_pwrdm, mpu_next_state);
215 
216 	/* Enable IO-PAD and IO-CHAIN wakeups */
217 	per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
218 	core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
219 
220 	pwrdm_pre_transition(NULL);
221 
222 	/* PER */
223 	if (per_next_state == PWRDM_POWER_OFF) {
224 		error = cpu_cluster_pm_enter();
225 		if (error)
226 			return;
227 	}
228 
229 	/* CORE */
230 	if (core_next_state < PWRDM_POWER_ON) {
231 		if (core_next_state == PWRDM_POWER_OFF) {
232 			omap3_core_save_context();
233 			omap3_cm_save_context();
234 		}
235 	}
236 
237 	/* Configure PMIC signaling for I2C4 or sys_off_mode */
238 	omap3_vc_set_pmic_signaling(core_next_state);
239 
240 	omap3_intc_prepare_idle();
241 
242 	/*
243 	 * On EMU/HS devices ROM code restores a SRDC value
244 	 * from scratchpad which has automatic self refresh on timeout
245 	 * of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
246 	 * Hence store/restore the SDRC_POWER register here.
247 	 */
248 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
249 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
250 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
251 	    core_next_state == PWRDM_POWER_OFF)
252 		sdrc_pwr = sdrc_read_reg(SDRC_POWER);
253 
254 	/*
255 	 * omap3_arm_context is the location where some ARM context
256 	 * get saved. The rest is placed on the stack, and restored
257 	 * from there before resuming.
258 	 */
259 	if (save_state)
260 		omap34xx_save_context(omap3_arm_context);
261 	if (save_state == 1 || save_state == 3)
262 		cpu_suspend(save_state, omap34xx_do_sram_idle);
263 	else
264 		omap34xx_do_sram_idle(save_state);
265 
266 	/* Restore normal SDRC POWER settings */
267 	if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
268 	    (omap_type() == OMAP2_DEVICE_TYPE_EMU ||
269 	     omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
270 	    core_next_state == PWRDM_POWER_OFF)
271 		sdrc_write_reg(sdrc_pwr, SDRC_POWER);
272 
273 	/* CORE */
274 	if (core_next_state < PWRDM_POWER_ON &&
275 	    pwrdm_read_prev_pwrst(core_pwrdm) == PWRDM_POWER_OFF) {
276 		omap3_core_restore_context();
277 		omap3_cm_restore_context();
278 		omap3_sram_restore_context();
279 		omap2_sms_restore_context();
280 	} else {
281 		/*
282 		 * In off-mode resume path above, omap3_core_restore_context
283 		 * also handles the INTC autoidle restore done here so limit
284 		 * this to non-off mode resume paths so we don't do it twice.
285 		 */
286 		omap3_intc_resume_idle();
287 	}
288 
289 	pwrdm_post_transition(NULL);
290 
291 	/* PER */
292 	if (per_next_state == PWRDM_POWER_OFF)
293 		cpu_cluster_pm_exit();
294 }
295 
296 static void omap3_pm_idle(void)
297 {
298 	if (omap_irq_pending())
299 		return;
300 
301 	omap_sram_idle();
302 }
303 
304 #ifdef CONFIG_SUSPEND
305 static int omap3_pm_suspend(void)
306 {
307 	struct power_state *pwrst;
308 	int state, ret = 0;
309 
310 	/* Read current next_pwrsts */
311 	list_for_each_entry(pwrst, &pwrst_list, node)
312 		pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
313 	/* Set ones wanted by suspend */
314 	list_for_each_entry(pwrst, &pwrst_list, node) {
315 		if (omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state))
316 			goto restore;
317 		if (pwrdm_clear_all_prev_pwrst(pwrst->pwrdm))
318 			goto restore;
319 	}
320 
321 	omap3_intc_suspend();
322 
323 	omap_sram_idle();
324 
325 restore:
326 	/* Restore next_pwrsts */
327 	list_for_each_entry(pwrst, &pwrst_list, node) {
328 		state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
329 		if (state > pwrst->next_state) {
330 			pr_info("Powerdomain (%s) didn't enter target state %d\n",
331 				pwrst->pwrdm->name, pwrst->next_state);
332 			ret = -1;
333 		}
334 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
335 	}
336 	if (ret)
337 		pr_err("Could not enter target state in pm_suspend\n");
338 	else
339 		pr_info("Successfully put all powerdomains to target state\n");
340 
341 	return ret;
342 }
343 #else
344 #define omap3_pm_suspend NULL
345 #endif /* CONFIG_SUSPEND */
346 
347 static void __init prcm_setup_regs(void)
348 {
349 	omap3_ctrl_init();
350 
351 	omap3_prm_init_pm(cpu_is_omap3630(), omap3_has_iva());
352 }
353 
354 void omap3_pm_off_mode_enable(int enable)
355 {
356 	struct power_state *pwrst;
357 	u32 state;
358 
359 	if (enable)
360 		state = PWRDM_POWER_OFF;
361 	else
362 		state = PWRDM_POWER_RET;
363 
364 	list_for_each_entry(pwrst, &pwrst_list, node) {
365 		if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) &&
366 				pwrst->pwrdm == core_pwrdm &&
367 				state == PWRDM_POWER_OFF) {
368 			pwrst->next_state = PWRDM_POWER_RET;
369 			pr_warn("%s: Core OFF disabled due to errata i583\n",
370 				__func__);
371 		} else {
372 			pwrst->next_state = state;
373 		}
374 		omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
375 	}
376 }
377 
378 int omap3_pm_get_suspend_state(struct powerdomain *pwrdm)
379 {
380 	struct power_state *pwrst;
381 
382 	list_for_each_entry(pwrst, &pwrst_list, node) {
383 		if (pwrst->pwrdm == pwrdm)
384 			return pwrst->next_state;
385 	}
386 	return -EINVAL;
387 }
388 
389 int omap3_pm_set_suspend_state(struct powerdomain *pwrdm, int state)
390 {
391 	struct power_state *pwrst;
392 
393 	list_for_each_entry(pwrst, &pwrst_list, node) {
394 		if (pwrst->pwrdm == pwrdm) {
395 			pwrst->next_state = state;
396 			return 0;
397 		}
398 	}
399 	return -EINVAL;
400 }
401 
402 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
403 {
404 	struct power_state *pwrst;
405 
406 	if (!pwrdm->pwrsts)
407 		return 0;
408 
409 	pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
410 	if (!pwrst)
411 		return -ENOMEM;
412 	pwrst->pwrdm = pwrdm;
413 	pwrst->next_state = PWRDM_POWER_RET;
414 	list_add(&pwrst->node, &pwrst_list);
415 
416 	if (pwrdm_has_hdwr_sar(pwrdm))
417 		pwrdm_enable_hdwr_sar(pwrdm);
418 
419 	return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
420 }
421 
422 /*
423  * Push functions to SRAM
424  *
425  * The minimum set of functions is pushed to SRAM for execution:
426  * - omap3_do_wfi for erratum i581 WA,
427  */
428 void omap_push_sram_idle(void)
429 {
430 	omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
431 }
432 
433 static void __init pm_errata_configure(void)
434 {
435 	if (cpu_is_omap3630()) {
436 		pm34xx_errata |= PM_RTA_ERRATUM_i608;
437 		/* Enable the l2 cache toggling in sleep logic */
438 		enable_omap3630_toggle_l2_on_restore();
439 		if (omap_rev() < OMAP3630_REV_ES1_2)
440 			pm34xx_errata |= (PM_SDRC_WAKEUP_ERRATUM_i583 |
441 					  PM_PER_MEMORIES_ERRATUM_i582);
442 	} else if (cpu_is_omap34xx()) {
443 		pm34xx_errata |= PM_PER_MEMORIES_ERRATUM_i582;
444 	}
445 }
446 
447 int __init omap3_pm_init(void)
448 {
449 	struct power_state *pwrst, *tmp;
450 	struct clockdomain *neon_clkdm, *mpu_clkdm, *per_clkdm, *wkup_clkdm;
451 	int ret;
452 
453 	if (!omap3_has_io_chain_ctrl())
454 		pr_warn("PM: no software I/O chain control; some wakeups may be lost\n");
455 
456 	pm_errata_configure();
457 
458 	/* XXX prcm_setup_regs needs to be before enabling hw
459 	 * supervised mode for powerdomains */
460 	prcm_setup_regs();
461 
462 	ret = request_irq(omap_prcm_event_to_irq("wkup"),
463 		_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
464 
465 	if (ret) {
466 		pr_err("pm: Failed to request pm_wkup irq\n");
467 		goto err1;
468 	}
469 
470 	/* IO interrupt is shared with mux code */
471 	ret = request_irq(omap_prcm_event_to_irq("io"),
472 		_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
473 		omap3_pm_init);
474 
475 	if (ret) {
476 		pr_err("pm: Failed to request pm_io irq\n");
477 		goto err2;
478 	}
479 
480 	ret = pwrdm_for_each(pwrdms_setup, NULL);
481 	if (ret) {
482 		pr_err("Failed to setup powerdomains\n");
483 		goto err3;
484 	}
485 
486 	(void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
487 
488 	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
489 	if (mpu_pwrdm == NULL) {
490 		pr_err("Failed to get mpu_pwrdm\n");
491 		ret = -EINVAL;
492 		goto err3;
493 	}
494 
495 	neon_pwrdm = pwrdm_lookup("neon_pwrdm");
496 	per_pwrdm = pwrdm_lookup("per_pwrdm");
497 	core_pwrdm = pwrdm_lookup("core_pwrdm");
498 
499 	neon_clkdm = clkdm_lookup("neon_clkdm");
500 	mpu_clkdm = clkdm_lookup("mpu_clkdm");
501 	per_clkdm = clkdm_lookup("per_clkdm");
502 	wkup_clkdm = clkdm_lookup("wkup_clkdm");
503 
504 	omap_common_suspend_init(omap3_pm_suspend);
505 
506 	arm_pm_idle = omap3_pm_idle;
507 	omap3_idle_init();
508 
509 	/*
510 	 * RTA is disabled during initialization as per erratum i608
511 	 * it is safer to disable RTA by the bootloader, but we would like
512 	 * to be doubly sure here and prevent any mishaps.
513 	 */
514 	if (IS_PM34XX_ERRATUM(PM_RTA_ERRATUM_i608))
515 		omap3630_ctrl_disable_rta();
516 
517 	/*
518 	 * The UART3/4 FIFO and the sidetone memory in McBSP2/3 are
519 	 * not correctly reset when the PER powerdomain comes back
520 	 * from OFF or OSWR when the CORE powerdomain is kept active.
521 	 * See OMAP36xx Erratum i582 "PER Domain reset issue after
522 	 * Domain-OFF/OSWR Wakeup".  This wakeup dependency is not a
523 	 * complete workaround.  The kernel must also prevent the PER
524 	 * powerdomain from going to OSWR/OFF while the CORE
525 	 * powerdomain is not going to OSWR/OFF.  And if PER last
526 	 * power state was off while CORE last power state was ON, the
527 	 * UART3/4 and McBSP2/3 SIDETONE devices need to run a
528 	 * self-test using their loopback tests; if that fails, those
529 	 * devices are unusable until the PER/CORE can complete a transition
530 	 * from ON to OSWR/OFF and then back to ON.
531 	 *
532 	 * XXX Technically this workaround is only needed if off-mode
533 	 * or OSWR is enabled.
534 	 */
535 	if (IS_PM34XX_ERRATUM(PM_PER_MEMORIES_ERRATUM_i582))
536 		clkdm_add_wkdep(per_clkdm, wkup_clkdm);
537 
538 	clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
539 	if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
540 		omap3_secure_ram_storage =
541 			kmalloc(OMAP3_SAVE_SECURE_RAM_SZ, GFP_KERNEL);
542 		if (!omap3_secure_ram_storage)
543 			pr_err("Memory allocation failed when allocating for secure sram context\n");
544 
545 		local_irq_disable();
546 
547 		omap3_save_secure_ram_context();
548 
549 		local_irq_enable();
550 	}
551 
552 	omap3_save_scratchpad_contents();
553 	return ret;
554 
555 err3:
556 	list_for_each_entry_safe(pwrst, tmp, &pwrst_list, node) {
557 		list_del(&pwrst->node);
558 		kfree(pwrst);
559 	}
560 	free_irq(omap_prcm_event_to_irq("io"), omap3_pm_init);
561 err2:
562 	free_irq(omap_prcm_event_to_irq("wkup"), NULL);
563 err1:
564 	return ret;
565 }
566