1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Power Management Service Unit(PMSU) support for Armada 370/XP platforms.
4 *
5 * Copyright (C) 2012 Marvell
6 *
7 * Yehuda Yitschak <yehuday@marvell.com>
8 * Gregory Clement <gregory.clement@free-electrons.com>
9 * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
10 *
11 * The Armada 370 and Armada XP SOCs have a power management service
12 * unit which is responsible for powering down and waking up CPUs and
13 * other SOC units
14 */
15
16#define pr_fmt(fmt) "mvebu-pmsu: " fmt
17
18#include <linux/clk.h>
19#include <linux/cpu_pm.h>
20#include <linux/delay.h>
21#include <linux/init.h>
22#include <linux/io.h>
23#include <linux/kernel.h>
24#include <linux/mbus.h>
25#include <linux/mvebu-pmsu.h>
26#include <linux/of.h>
27#include <linux/of_address.h>
28#include <linux/platform_device.h>
29#include <linux/resource.h>
30#include <linux/slab.h>
31#include <linux/smp.h>
32#include <asm/cacheflush.h>
33#include <asm/cp15.h>
34#include <asm/smp_scu.h>
35#include <asm/smp_plat.h>
36#include <asm/suspend.h>
37#include <asm/tlbflush.h>
38#include "common.h"
39#include "pmsu.h"
40
41#define PMSU_BASE_OFFSET    0x100
42#define PMSU_REG_SIZE	    0x1000
43
44/* PMSU MP registers */
45#define PMSU_CONTROL_AND_CONFIG(cpu)	    ((cpu * 0x100) + 0x104)
46#define PMSU_CONTROL_AND_CONFIG_DFS_REQ		BIT(18)
47#define PMSU_CONTROL_AND_CONFIG_PWDDN_REQ	BIT(16)
48#define PMSU_CONTROL_AND_CONFIG_L2_PWDDN	BIT(20)
49
50#define PMSU_CPU_POWER_DOWN_CONTROL(cpu)    ((cpu * 0x100) + 0x108)
51
52#define PMSU_CPU_POWER_DOWN_DIS_SNP_Q_SKIP	BIT(0)
53
54#define PMSU_STATUS_AND_MASK(cpu)	    ((cpu * 0x100) + 0x10c)
55#define PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT	BIT(16)
56#define PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT	BIT(17)
57#define PMSU_STATUS_AND_MASK_IRQ_WAKEUP		BIT(20)
58#define PMSU_STATUS_AND_MASK_FIQ_WAKEUP		BIT(21)
59#define PMSU_STATUS_AND_MASK_DBG_WAKEUP		BIT(22)
60#define PMSU_STATUS_AND_MASK_IRQ_MASK		BIT(24)
61#define PMSU_STATUS_AND_MASK_FIQ_MASK		BIT(25)
62
63#define PMSU_EVENT_STATUS_AND_MASK(cpu)     ((cpu * 0x100) + 0x120)
64#define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE        BIT(1)
65#define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK   BIT(17)
66
67#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124)
68
69/* PMSU fabric registers */
70#define L2C_NFABRIC_PM_CTL		    0x4
71#define L2C_NFABRIC_PM_CTL_PWR_DOWN		BIT(20)
72
73/* PMSU delay registers */
74#define PMSU_POWERDOWN_DELAY		    0xF04
75#define PMSU_POWERDOWN_DELAY_PMU		BIT(1)
76#define PMSU_POWERDOWN_DELAY_MASK		0xFFFE
77#define PMSU_DFLT_ARMADA38X_DELAY	        0x64
78
79/* CA9 MPcore SoC Control registers */
80
81#define MPCORE_RESET_CTL		    0x64
82#define MPCORE_RESET_CTL_L2			BIT(0)
83#define MPCORE_RESET_CTL_DEBUG			BIT(16)
84
85#define SRAM_PHYS_BASE  0xFFFF0000
86#define BOOTROM_BASE    0xFFF00000
87#define BOOTROM_SIZE    0x100000
88
89#define ARMADA_370_CRYPT0_ENG_TARGET   0x9
90#define ARMADA_370_CRYPT0_ENG_ATTR     0x1
91
92extern void ll_disable_coherency(void);
93extern void ll_enable_coherency(void);
94
95extern void armada_370_xp_cpu_resume(void);
96extern void armada_38x_cpu_resume(void);
97
98static phys_addr_t pmsu_mp_phys_base;
99static void __iomem *pmsu_mp_base;
100
101static void *mvebu_cpu_resume;
102
103static const struct of_device_id of_pmsu_table[] = {
104	{ .compatible = "marvell,armada-370-pmsu", },
105	{ .compatible = "marvell,armada-370-xp-pmsu", },
106	{ .compatible = "marvell,armada-380-pmsu", },
107	{ /* end of list */ },
108};
109
110void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
111{
112	writel(__pa_symbol(boot_addr), pmsu_mp_base +
113		PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
114}
115
116extern unsigned char mvebu_boot_wa_start[];
117extern unsigned char mvebu_boot_wa_end[];
118
119/*
120 * This function sets up the boot address workaround needed for SMP
121 * boot on Armada 375 Z1 and cpuidle on Armada 370. It unmaps the
122 * BootROM Mbus window, and instead remaps a crypto SRAM into which a
123 * custom piece of code is copied to replace the problematic BootROM.
124 */
125int mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,
126			     unsigned int crypto_eng_attribute,
127			     phys_addr_t resume_addr_reg)
128{
129	void __iomem *sram_virt_base;
130	u32 code_len = mvebu_boot_wa_end - mvebu_boot_wa_start;
131
132	mvebu_mbus_del_window(BOOTROM_BASE, BOOTROM_SIZE);
133	mvebu_mbus_add_window_by_id(crypto_eng_target, crypto_eng_attribute,
134				    SRAM_PHYS_BASE, SZ_64K);
135
136	sram_virt_base = ioremap(SRAM_PHYS_BASE, SZ_64K);
137	if (!sram_virt_base) {
138		pr_err("Unable to map SRAM to setup the boot address WA\n");
139		return -ENOMEM;
140	}
141
142	memcpy(sram_virt_base, &mvebu_boot_wa_start, code_len);
143
144	/*
145	 * The last word of the code copied in SRAM must contain the
146	 * physical base address of the PMSU register. We
147	 * intentionally store this address in the native endianness
148	 * of the system.
149	 */
150	__raw_writel((unsigned long)resume_addr_reg,
151		     sram_virt_base + code_len - 4);
152
153	iounmap(sram_virt_base);
154
155	return 0;
156}
157
158static int __init mvebu_v7_pmsu_init(void)
159{
160	struct device_node *np;
161	struct resource res;
162	int ret = 0;
163
164	np = of_find_matching_node(NULL, of_pmsu_table);
165	if (!np)
166		return 0;
167
168	pr_info("Initializing Power Management Service Unit\n");
169
170	if (of_address_to_resource(np, 0, &res)) {
171		pr_err("unable to get resource\n");
172		ret = -ENOENT;
173		goto out;
174	}
175
176	if (of_device_is_compatible(np, "marvell,armada-370-xp-pmsu")) {
177		pr_warn(FW_WARN "deprecated pmsu binding\n");
178		res.start = res.start - PMSU_BASE_OFFSET;
179		res.end = res.start + PMSU_REG_SIZE - 1;
180	}
181
182	if (!request_mem_region(res.start, resource_size(&res),
183				np->full_name)) {
184		pr_err("unable to request region\n");
185		ret = -EBUSY;
186		goto out;
187	}
188
189	pmsu_mp_phys_base = res.start;
190
191	pmsu_mp_base = ioremap(res.start, resource_size(&res));
192	if (!pmsu_mp_base) {
193		pr_err("unable to map registers\n");
194		release_mem_region(res.start, resource_size(&res));
195		ret = -ENOMEM;
196		goto out;
197	}
198
199 out:
200	of_node_put(np);
201	return ret;
202}
203
204static void mvebu_v7_pmsu_enable_l2_powerdown_onidle(void)
205{
206	u32 reg;
207
208	if (pmsu_mp_base == NULL)
209		return;
210
211	/* Enable L2 & Fabric powerdown in Deep-Idle mode - Fabric */
212	reg = readl(pmsu_mp_base + L2C_NFABRIC_PM_CTL);
213	reg |= L2C_NFABRIC_PM_CTL_PWR_DOWN;
214	writel(reg, pmsu_mp_base + L2C_NFABRIC_PM_CTL);
215}
216
217enum pmsu_idle_prepare_flags {
218	PMSU_PREPARE_NORMAL = 0,
219	PMSU_PREPARE_DEEP_IDLE = BIT(0),
220	PMSU_PREPARE_SNOOP_DISABLE = BIT(1),
221};
222
223/* No locking is needed because we only access per-CPU registers */
224static int mvebu_v7_pmsu_idle_prepare(unsigned long flags)
225{
226	unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
227	u32 reg;
228
229	if (pmsu_mp_base == NULL)
230		return -EINVAL;
231
232	/*
233	 * Adjust the PMSU configuration to wait for WFI signal, enable
234	 * IRQ and FIQ as wakeup events, set wait for snoop queue empty
235	 * indication and mask IRQ and FIQ from CPU
236	 */
237	reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
238	reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT    |
239	       PMSU_STATUS_AND_MASK_IRQ_WAKEUP       |
240	       PMSU_STATUS_AND_MASK_FIQ_WAKEUP       |
241	       PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT |
242	       PMSU_STATUS_AND_MASK_IRQ_MASK         |
243	       PMSU_STATUS_AND_MASK_FIQ_MASK;
244	writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
245
246	reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
247	/* ask HW to power down the L2 Cache if needed */
248	if (flags & PMSU_PREPARE_DEEP_IDLE)
249		reg |= PMSU_CONTROL_AND_CONFIG_L2_PWDDN;
250
251	/* request power down */
252	reg |= PMSU_CONTROL_AND_CONFIG_PWDDN_REQ;
253	writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
254
255	if (flags & PMSU_PREPARE_SNOOP_DISABLE) {
256		/* Disable snoop disable by HW - SW is taking care of it */
257		reg = readl(pmsu_mp_base + PMSU_CPU_POWER_DOWN_CONTROL(hw_cpu));
258		reg |= PMSU_CPU_POWER_DOWN_DIS_SNP_Q_SKIP;
259		writel(reg, pmsu_mp_base + PMSU_CPU_POWER_DOWN_CONTROL(hw_cpu));
260	}
261
262	return 0;
263}
264
265int armada_370_xp_pmsu_idle_enter(unsigned long deepidle)
266{
267	unsigned long flags = PMSU_PREPARE_SNOOP_DISABLE;
268	int ret;
269
270	if (deepidle)
271		flags |= PMSU_PREPARE_DEEP_IDLE;
272
273	ret = mvebu_v7_pmsu_idle_prepare(flags);
274	if (ret)
275		return ret;
276
277	v7_exit_coherency_flush(all);
278
279	ll_disable_coherency();
280
281	dsb();
282
283	wfi();
284
285	/* If we are here, wfi failed. As processors run out of
286	 * coherency for some time, tlbs might be stale, so flush them
287	 */
288	local_flush_tlb_all();
289
290	ll_enable_coherency();
291
292	/* Test the CR_C bit and set it if it was cleared */
293	asm volatile(
294	".arch	armv7-a\n\t"
295	"mrc	p15, 0, r0, c1, c0, 0 \n\t"
296	"tst	r0, %0 \n\t"
297	"orreq	r0, r0, #(1 << 2) \n\t"
298	"mcreq	p15, 0, r0, c1, c0, 0 \n\t"
299	"isb	"
300	: : "Ir" (CR_C) : "r0");
301
302	pr_debug("Failed to suspend the system\n");
303
304	return 0;
305}
306
307static int armada_370_xp_cpu_suspend(unsigned long deepidle)
308{
309	return cpu_suspend(deepidle, armada_370_xp_pmsu_idle_enter);
310}
311
312int armada_38x_do_cpu_suspend(unsigned long deepidle)
313{
314	unsigned long flags = 0;
315
316	if (deepidle)
317		flags |= PMSU_PREPARE_DEEP_IDLE;
318
319	mvebu_v7_pmsu_idle_prepare(flags);
320	/*
321	 * Already flushed cache, but do it again as the outer cache
322	 * functions dirty the cache with spinlocks
323	 */
324	v7_exit_coherency_flush(louis);
325
326	scu_power_mode(mvebu_get_scu_base(), SCU_PM_POWEROFF);
327
328	cpu_do_idle();
329
330	return 1;
331}
332
333static int armada_38x_cpu_suspend(unsigned long deepidle)
334{
335	return cpu_suspend(false, armada_38x_do_cpu_suspend);
336}
337
338/* No locking is needed because we only access per-CPU registers */
339void mvebu_v7_pmsu_idle_exit(void)
340{
341	unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
342	u32 reg;
343
344	if (pmsu_mp_base == NULL)
345		return;
346	/* cancel ask HW to power down the L2 Cache if possible */
347	reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
348	reg &= ~PMSU_CONTROL_AND_CONFIG_L2_PWDDN;
349	writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
350
351	/* cancel Enable wakeup events and mask interrupts */
352	reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
353	reg &= ~(PMSU_STATUS_AND_MASK_IRQ_WAKEUP | PMSU_STATUS_AND_MASK_FIQ_WAKEUP);
354	reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
355	reg &= ~PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT;
356	reg &= ~(PMSU_STATUS_AND_MASK_IRQ_MASK | PMSU_STATUS_AND_MASK_FIQ_MASK);
357	writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
358}
359
360static int mvebu_v7_cpu_pm_notify(struct notifier_block *self,
361				    unsigned long action, void *hcpu)
362{
363	if (action == CPU_PM_ENTER) {
364		unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
365		mvebu_pmsu_set_cpu_boot_addr(hw_cpu, mvebu_cpu_resume);
366	} else if (action == CPU_PM_EXIT) {
367		mvebu_v7_pmsu_idle_exit();
368	}
369
370	return NOTIFY_OK;
371}
372
373static struct notifier_block mvebu_v7_cpu_pm_notifier = {
374	.notifier_call = mvebu_v7_cpu_pm_notify,
375};
376
377static struct platform_device mvebu_v7_cpuidle_device;
378
379static int broken_idle(struct device_node *np)
380{
381	if (of_property_read_bool(np, "broken-idle")) {
382		pr_warn("CPU idle is currently broken: disabling\n");
383		return 1;
384	}
385
386	return 0;
387}
388
389static __init int armada_370_cpuidle_init(void)
390{
391	struct device_node *np;
392	phys_addr_t redirect_reg;
393
394	np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
395	if (!np)
396		return -ENODEV;
397
398	if (broken_idle(np))
399		goto end;
400
401	/*
402	 * On Armada 370, there is "a slow exit process from the deep
403	 * idle state due to heavy L1/L2 cache cleanup operations
404	 * performed by the BootROM software". To avoid this, we
405	 * replace the restart code of the bootrom by a a simple jump
406	 * to the boot address. Then the code located at this boot
407	 * address will take care of the initialization.
408	 */
409	redirect_reg = pmsu_mp_phys_base + PMSU_BOOT_ADDR_REDIRECT_OFFSET(0);
410	mvebu_setup_boot_addr_wa(ARMADA_370_CRYPT0_ENG_TARGET,
411				 ARMADA_370_CRYPT0_ENG_ATTR,
412				 redirect_reg);
413
414	mvebu_cpu_resume = armada_370_xp_cpu_resume;
415	mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
416	mvebu_v7_cpuidle_device.name = "cpuidle-armada-370";
417
418end:
419	of_node_put(np);
420	return 0;
421}
422
423static __init int armada_38x_cpuidle_init(void)
424{
425	struct device_node *np;
426	void __iomem *mpsoc_base;
427	u32 reg;
428
429	pr_warn("CPU idle is currently broken on Armada 38x: disabling\n");
430	return 0;
431
432	np = of_find_compatible_node(NULL, NULL,
433				     "marvell,armada-380-coherency-fabric");
434	if (!np)
435		return -ENODEV;
436
437	if (broken_idle(np))
438		goto end;
439
440	of_node_put(np);
441
442	np = of_find_compatible_node(NULL, NULL,
443				     "marvell,armada-380-mpcore-soc-ctrl");
444	if (!np)
445		return -ENODEV;
446	mpsoc_base = of_iomap(np, 0);
447	BUG_ON(!mpsoc_base);
448
449	/* Set up reset mask when powering down the cpus */
450	reg = readl(mpsoc_base + MPCORE_RESET_CTL);
451	reg |= MPCORE_RESET_CTL_L2;
452	reg |= MPCORE_RESET_CTL_DEBUG;
453	writel(reg, mpsoc_base + MPCORE_RESET_CTL);
454	iounmap(mpsoc_base);
455
456	/* Set up delay */
457	reg = readl(pmsu_mp_base + PMSU_POWERDOWN_DELAY);
458	reg &= ~PMSU_POWERDOWN_DELAY_MASK;
459	reg |= PMSU_DFLT_ARMADA38X_DELAY;
460	reg |= PMSU_POWERDOWN_DELAY_PMU;
461	writel(reg, pmsu_mp_base + PMSU_POWERDOWN_DELAY);
462
463	mvebu_cpu_resume = armada_38x_cpu_resume;
464	mvebu_v7_cpuidle_device.dev.platform_data = armada_38x_cpu_suspend;
465	mvebu_v7_cpuidle_device.name = "cpuidle-armada-38x";
466
467end:
468	of_node_put(np);
469	return 0;
470}
471
472static __init int armada_xp_cpuidle_init(void)
473{
474	struct device_node *np;
475
476	np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
477	if (!np)
478		return -ENODEV;
479
480	if (broken_idle(np))
481		goto end;
482
483	mvebu_cpu_resume = armada_370_xp_cpu_resume;
484	mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
485	mvebu_v7_cpuidle_device.name = "cpuidle-armada-xp";
486
487end:
488	of_node_put(np);
489	return 0;
490}
491
492static int __init mvebu_v7_cpu_pm_init(void)
493{
494	struct device_node *np;
495	int ret;
496
497	np = of_find_matching_node(NULL, of_pmsu_table);
498	if (!np)
499		return 0;
500	of_node_put(np);
501
502	/*
503	 * Currently the CPU idle support for Armada 38x is broken, as
504	 * the CPU hotplug uses some of the CPU idle functions it is
505	 * broken too, so let's disable it
506	 */
507	if (of_machine_is_compatible("marvell,armada380")) {
508		cpu_hotplug_disable();
509		pr_warn("CPU hotplug support is currently broken on Armada 38x: disabling\n");
510	}
511
512	if (of_machine_is_compatible("marvell,armadaxp"))
513		ret = armada_xp_cpuidle_init();
514	else if (of_machine_is_compatible("marvell,armada370"))
515		ret = armada_370_cpuidle_init();
516	else if (of_machine_is_compatible("marvell,armada380"))
517		ret = armada_38x_cpuidle_init();
518	else
519		return 0;
520
521	if (ret)
522		return ret;
523
524	mvebu_v7_pmsu_enable_l2_powerdown_onidle();
525	if (mvebu_v7_cpuidle_device.name)
526		platform_device_register(&mvebu_v7_cpuidle_device);
527	cpu_pm_register_notifier(&mvebu_v7_cpu_pm_notifier);
528
529	return 0;
530}
531
532arch_initcall(mvebu_v7_cpu_pm_init);
533early_initcall(mvebu_v7_pmsu_init);
534
535static void mvebu_pmsu_dfs_request_local(void *data)
536{
537	u32 reg;
538	u32 cpu = smp_processor_id();
539	unsigned long flags;
540
541	local_irq_save(flags);
542
543	/* Prepare to enter idle */
544	reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
545	reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT |
546	       PMSU_STATUS_AND_MASK_IRQ_MASK     |
547	       PMSU_STATUS_AND_MASK_FIQ_MASK;
548	writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
549
550	/* Request the DFS transition */
551	reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
552	reg |= PMSU_CONTROL_AND_CONFIG_DFS_REQ;
553	writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
554
555	/* The fact of entering idle will trigger the DFS transition */
556	wfi();
557
558	/*
559	 * We're back from idle, the DFS transition has completed,
560	 * clear the idle wait indication.
561	 */
562	reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
563	reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
564	writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
565
566	local_irq_restore(flags);
567}
568
569int mvebu_pmsu_dfs_request(int cpu)
570{
571	unsigned long timeout;
572	int hwcpu = cpu_logical_map(cpu);
573	u32 reg;
574
575	/* Clear any previous DFS DONE event */
576	reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
577	reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE;
578	writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
579
580	/* Mask the DFS done interrupt, since we are going to poll */
581	reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
582	reg |= PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
583	writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
584
585	/* Trigger the DFS on the appropriate CPU */
586	smp_call_function_single(cpu, mvebu_pmsu_dfs_request_local,
587				 NULL, false);
588
589	/* Poll until the DFS done event is generated */
590	timeout = jiffies + HZ;
591	while (time_before(jiffies, timeout)) {
592		reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
593		if (reg & PMSU_EVENT_STATUS_AND_MASK_DFS_DONE)
594			break;
595		udelay(10);
596	}
597
598	if (time_after(jiffies, timeout))
599		return -ETIME;
600
601	/* Restore the DFS mask to its original state */
602	reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
603	reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
604	writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
605
606	return 0;
607}
608