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_address.h>
27 #include <linux/of_device.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
92 extern void ll_disable_coherency(void);
93 extern void ll_enable_coherency(void);
94
95 extern void armada_370_xp_cpu_resume(void);
96 extern void armada_38x_cpu_resume(void);
97
98 static phys_addr_t pmsu_mp_phys_base;
99 static void __iomem *pmsu_mp_base;
100
101 static void *mvebu_cpu_resume;
102
103 static 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
mvebu_pmsu_set_cpu_boot_addr(int hw_cpu,void * boot_addr)110 void 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
116 extern unsigned char mvebu_boot_wa_start[];
117 extern 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 */
mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,unsigned int crypto_eng_attribute,phys_addr_t resume_addr_reg)125 int 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
mvebu_v7_pmsu_init(void)158 static 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
mvebu_v7_pmsu_enable_l2_powerdown_onidle(void)204 static 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
217 enum 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 */
mvebu_v7_pmsu_idle_prepare(unsigned long flags)224 static 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
armada_370_xp_pmsu_idle_enter(unsigned long deepidle)265 int 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 "mrc p15, 0, r0, c1, c0, 0 \n\t"
295 "tst r0, %0 \n\t"
296 "orreq r0, r0, #(1 << 2) \n\t"
297 "mcreq p15, 0, r0, c1, c0, 0 \n\t"
298 "isb "
299 : : "Ir" (CR_C) : "r0");
300
301 pr_debug("Failed to suspend the system\n");
302
303 return 0;
304 }
305
armada_370_xp_cpu_suspend(unsigned long deepidle)306 static int armada_370_xp_cpu_suspend(unsigned long deepidle)
307 {
308 return cpu_suspend(deepidle, armada_370_xp_pmsu_idle_enter);
309 }
310
armada_38x_do_cpu_suspend(unsigned long deepidle)311 int armada_38x_do_cpu_suspend(unsigned long deepidle)
312 {
313 unsigned long flags = 0;
314
315 if (deepidle)
316 flags |= PMSU_PREPARE_DEEP_IDLE;
317
318 mvebu_v7_pmsu_idle_prepare(flags);
319 /*
320 * Already flushed cache, but do it again as the outer cache
321 * functions dirty the cache with spinlocks
322 */
323 v7_exit_coherency_flush(louis);
324
325 scu_power_mode(mvebu_get_scu_base(), SCU_PM_POWEROFF);
326
327 cpu_do_idle();
328
329 return 1;
330 }
331
armada_38x_cpu_suspend(unsigned long deepidle)332 static int armada_38x_cpu_suspend(unsigned long deepidle)
333 {
334 return cpu_suspend(false, armada_38x_do_cpu_suspend);
335 }
336
337 /* No locking is needed because we only access per-CPU registers */
mvebu_v7_pmsu_idle_exit(void)338 void mvebu_v7_pmsu_idle_exit(void)
339 {
340 unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
341 u32 reg;
342
343 if (pmsu_mp_base == NULL)
344 return;
345 /* cancel ask HW to power down the L2 Cache if possible */
346 reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
347 reg &= ~PMSU_CONTROL_AND_CONFIG_L2_PWDDN;
348 writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
349
350 /* cancel Enable wakeup events and mask interrupts */
351 reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
352 reg &= ~(PMSU_STATUS_AND_MASK_IRQ_WAKEUP | PMSU_STATUS_AND_MASK_FIQ_WAKEUP);
353 reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
354 reg &= ~PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT;
355 reg &= ~(PMSU_STATUS_AND_MASK_IRQ_MASK | PMSU_STATUS_AND_MASK_FIQ_MASK);
356 writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
357 }
358
mvebu_v7_cpu_pm_notify(struct notifier_block * self,unsigned long action,void * hcpu)359 static int mvebu_v7_cpu_pm_notify(struct notifier_block *self,
360 unsigned long action, void *hcpu)
361 {
362 if (action == CPU_PM_ENTER) {
363 unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
364 mvebu_pmsu_set_cpu_boot_addr(hw_cpu, mvebu_cpu_resume);
365 } else if (action == CPU_PM_EXIT) {
366 mvebu_v7_pmsu_idle_exit();
367 }
368
369 return NOTIFY_OK;
370 }
371
372 static struct notifier_block mvebu_v7_cpu_pm_notifier = {
373 .notifier_call = mvebu_v7_cpu_pm_notify,
374 };
375
376 static struct platform_device mvebu_v7_cpuidle_device;
377
broken_idle(struct device_node * np)378 static int broken_idle(struct device_node *np)
379 {
380 if (of_property_read_bool(np, "broken-idle")) {
381 pr_warn("CPU idle is currently broken: disabling\n");
382 return 1;
383 }
384
385 return 0;
386 }
387
armada_370_cpuidle_init(void)388 static __init int armada_370_cpuidle_init(void)
389 {
390 struct device_node *np;
391 phys_addr_t redirect_reg;
392
393 np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
394 if (!np)
395 return -ENODEV;
396
397 if (broken_idle(np))
398 goto end;
399
400 /*
401 * On Armada 370, there is "a slow exit process from the deep
402 * idle state due to heavy L1/L2 cache cleanup operations
403 * performed by the BootROM software". To avoid this, we
404 * replace the restart code of the bootrom by a a simple jump
405 * to the boot address. Then the code located at this boot
406 * address will take care of the initialization.
407 */
408 redirect_reg = pmsu_mp_phys_base + PMSU_BOOT_ADDR_REDIRECT_OFFSET(0);
409 mvebu_setup_boot_addr_wa(ARMADA_370_CRYPT0_ENG_TARGET,
410 ARMADA_370_CRYPT0_ENG_ATTR,
411 redirect_reg);
412
413 mvebu_cpu_resume = armada_370_xp_cpu_resume;
414 mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
415 mvebu_v7_cpuidle_device.name = "cpuidle-armada-370";
416
417 end:
418 of_node_put(np);
419 return 0;
420 }
421
armada_38x_cpuidle_init(void)422 static __init int armada_38x_cpuidle_init(void)
423 {
424 struct device_node *np;
425 void __iomem *mpsoc_base;
426 u32 reg;
427
428 pr_warn("CPU idle is currently broken on Armada 38x: disabling\n");
429 return 0;
430
431 np = of_find_compatible_node(NULL, NULL,
432 "marvell,armada-380-coherency-fabric");
433 if (!np)
434 return -ENODEV;
435
436 if (broken_idle(np))
437 goto end;
438
439 of_node_put(np);
440
441 np = of_find_compatible_node(NULL, NULL,
442 "marvell,armada-380-mpcore-soc-ctrl");
443 if (!np)
444 return -ENODEV;
445 mpsoc_base = of_iomap(np, 0);
446 BUG_ON(!mpsoc_base);
447
448 /* Set up reset mask when powering down the cpus */
449 reg = readl(mpsoc_base + MPCORE_RESET_CTL);
450 reg |= MPCORE_RESET_CTL_L2;
451 reg |= MPCORE_RESET_CTL_DEBUG;
452 writel(reg, mpsoc_base + MPCORE_RESET_CTL);
453 iounmap(mpsoc_base);
454
455 /* Set up delay */
456 reg = readl(pmsu_mp_base + PMSU_POWERDOWN_DELAY);
457 reg &= ~PMSU_POWERDOWN_DELAY_MASK;
458 reg |= PMSU_DFLT_ARMADA38X_DELAY;
459 reg |= PMSU_POWERDOWN_DELAY_PMU;
460 writel(reg, pmsu_mp_base + PMSU_POWERDOWN_DELAY);
461
462 mvebu_cpu_resume = armada_38x_cpu_resume;
463 mvebu_v7_cpuidle_device.dev.platform_data = armada_38x_cpu_suspend;
464 mvebu_v7_cpuidle_device.name = "cpuidle-armada-38x";
465
466 end:
467 of_node_put(np);
468 return 0;
469 }
470
armada_xp_cpuidle_init(void)471 static __init int armada_xp_cpuidle_init(void)
472 {
473 struct device_node *np;
474
475 np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
476 if (!np)
477 return -ENODEV;
478
479 if (broken_idle(np))
480 goto end;
481
482 mvebu_cpu_resume = armada_370_xp_cpu_resume;
483 mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
484 mvebu_v7_cpuidle_device.name = "cpuidle-armada-xp";
485
486 end:
487 of_node_put(np);
488 return 0;
489 }
490
mvebu_v7_cpu_pm_init(void)491 static int __init mvebu_v7_cpu_pm_init(void)
492 {
493 struct device_node *np;
494 int ret;
495
496 np = of_find_matching_node(NULL, of_pmsu_table);
497 if (!np)
498 return 0;
499 of_node_put(np);
500
501 /*
502 * Currently the CPU idle support for Armada 38x is broken, as
503 * the CPU hotplug uses some of the CPU idle functions it is
504 * broken too, so let's disable it
505 */
506 if (of_machine_is_compatible("marvell,armada380")) {
507 cpu_hotplug_disable();
508 pr_warn("CPU hotplug support is currently broken on Armada 38x: disabling\n");
509 }
510
511 if (of_machine_is_compatible("marvell,armadaxp"))
512 ret = armada_xp_cpuidle_init();
513 else if (of_machine_is_compatible("marvell,armada370"))
514 ret = armada_370_cpuidle_init();
515 else if (of_machine_is_compatible("marvell,armada380"))
516 ret = armada_38x_cpuidle_init();
517 else
518 return 0;
519
520 if (ret)
521 return ret;
522
523 mvebu_v7_pmsu_enable_l2_powerdown_onidle();
524 if (mvebu_v7_cpuidle_device.name)
525 platform_device_register(&mvebu_v7_cpuidle_device);
526 cpu_pm_register_notifier(&mvebu_v7_cpu_pm_notifier);
527
528 return 0;
529 }
530
531 arch_initcall(mvebu_v7_cpu_pm_init);
532 early_initcall(mvebu_v7_pmsu_init);
533
mvebu_pmsu_dfs_request_local(void * data)534 static void mvebu_pmsu_dfs_request_local(void *data)
535 {
536 u32 reg;
537 u32 cpu = smp_processor_id();
538 unsigned long flags;
539
540 local_irq_save(flags);
541
542 /* Prepare to enter idle */
543 reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
544 reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT |
545 PMSU_STATUS_AND_MASK_IRQ_MASK |
546 PMSU_STATUS_AND_MASK_FIQ_MASK;
547 writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
548
549 /* Request the DFS transition */
550 reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
551 reg |= PMSU_CONTROL_AND_CONFIG_DFS_REQ;
552 writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
553
554 /* The fact of entering idle will trigger the DFS transition */
555 wfi();
556
557 /*
558 * We're back from idle, the DFS transition has completed,
559 * clear the idle wait indication.
560 */
561 reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
562 reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
563 writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
564
565 local_irq_restore(flags);
566 }
567
mvebu_pmsu_dfs_request(int cpu)568 int mvebu_pmsu_dfs_request(int cpu)
569 {
570 unsigned long timeout;
571 int hwcpu = cpu_logical_map(cpu);
572 u32 reg;
573
574 /* Clear any previous DFS DONE event */
575 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
576 reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE;
577 writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
578
579 /* Mask the DFS done interrupt, since we are going to poll */
580 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
581 reg |= PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
582 writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
583
584 /* Trigger the DFS on the appropriate CPU */
585 smp_call_function_single(cpu, mvebu_pmsu_dfs_request_local,
586 NULL, false);
587
588 /* Poll until the DFS done event is generated */
589 timeout = jiffies + HZ;
590 while (time_before(jiffies, timeout)) {
591 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
592 if (reg & PMSU_EVENT_STATUS_AND_MASK_DFS_DONE)
593 break;
594 udelay(10);
595 }
596
597 if (time_after(jiffies, timeout))
598 return -ETIME;
599
600 /* Restore the DFS mask to its original state */
601 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
602 reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
603 writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
604
605 return 0;
606 }
607