1 /*
2 * Power Management Service Unit(PMSU) support for Armada 370/XP platforms.
3 *
4 * Copyright (C) 2012 Marvell
5 *
6 * Yehuda Yitschak <yehuday@marvell.com>
7 * Gregory Clement <gregory.clement@free-electrons.com>
8 * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
9 *
10 * This file is licensed under the terms of the GNU General Public
11 * License version 2. This program is licensed "as is" without any
12 * warranty of any kind, whether express or implied.
13 *
14 * The Armada 370 and Armada XP SOCs have a power management service
15 * unit which is responsible for powering down and waking up CPUs and
16 * other SOC units
17 */
18
19 #define pr_fmt(fmt) "mvebu-pmsu: " fmt
20
21 #include <linux/clk.h>
22 #include <linux/cpu_pm.h>
23 #include <linux/cpufreq-dt.h>
24 #include <linux/delay.h>
25 #include <linux/init.h>
26 #include <linux/io.h>
27 #include <linux/kernel.h>
28 #include <linux/mbus.h>
29 #include <linux/of_address.h>
30 #include <linux/of_device.h>
31 #include <linux/platform_device.h>
32 #include <linux/pm_opp.h>
33 #include <linux/resource.h>
34 #include <linux/slab.h>
35 #include <linux/smp.h>
36 #include <asm/cacheflush.h>
37 #include <asm/cp15.h>
38 #include <asm/smp_scu.h>
39 #include <asm/smp_plat.h>
40 #include <asm/suspend.h>
41 #include <asm/tlbflush.h>
42 #include "common.h"
43
44
45 #define PMSU_BASE_OFFSET 0x100
46 #define PMSU_REG_SIZE 0x1000
47
48 /* PMSU MP registers */
49 #define PMSU_CONTROL_AND_CONFIG(cpu) ((cpu * 0x100) + 0x104)
50 #define PMSU_CONTROL_AND_CONFIG_DFS_REQ BIT(18)
51 #define PMSU_CONTROL_AND_CONFIG_PWDDN_REQ BIT(16)
52 #define PMSU_CONTROL_AND_CONFIG_L2_PWDDN BIT(20)
53
54 #define PMSU_CPU_POWER_DOWN_CONTROL(cpu) ((cpu * 0x100) + 0x108)
55
56 #define PMSU_CPU_POWER_DOWN_DIS_SNP_Q_SKIP BIT(0)
57
58 #define PMSU_STATUS_AND_MASK(cpu) ((cpu * 0x100) + 0x10c)
59 #define PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT BIT(16)
60 #define PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT BIT(17)
61 #define PMSU_STATUS_AND_MASK_IRQ_WAKEUP BIT(20)
62 #define PMSU_STATUS_AND_MASK_FIQ_WAKEUP BIT(21)
63 #define PMSU_STATUS_AND_MASK_DBG_WAKEUP BIT(22)
64 #define PMSU_STATUS_AND_MASK_IRQ_MASK BIT(24)
65 #define PMSU_STATUS_AND_MASK_FIQ_MASK BIT(25)
66
67 #define PMSU_EVENT_STATUS_AND_MASK(cpu) ((cpu * 0x100) + 0x120)
68 #define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE BIT(1)
69 #define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK BIT(17)
70
71 #define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124)
72
73 /* PMSU fabric registers */
74 #define L2C_NFABRIC_PM_CTL 0x4
75 #define L2C_NFABRIC_PM_CTL_PWR_DOWN BIT(20)
76
77 /* PMSU delay registers */
78 #define PMSU_POWERDOWN_DELAY 0xF04
79 #define PMSU_POWERDOWN_DELAY_PMU BIT(1)
80 #define PMSU_POWERDOWN_DELAY_MASK 0xFFFE
81 #define PMSU_DFLT_ARMADA38X_DELAY 0x64
82
83 /* CA9 MPcore SoC Control registers */
84
85 #define MPCORE_RESET_CTL 0x64
86 #define MPCORE_RESET_CTL_L2 BIT(0)
87 #define MPCORE_RESET_CTL_DEBUG BIT(16)
88
89 #define SRAM_PHYS_BASE 0xFFFF0000
90 #define BOOTROM_BASE 0xFFF00000
91 #define BOOTROM_SIZE 0x100000
92
93 #define ARMADA_370_CRYPT0_ENG_TARGET 0x9
94 #define ARMADA_370_CRYPT0_ENG_ATTR 0x1
95
96 extern void ll_disable_coherency(void);
97 extern void ll_enable_coherency(void);
98
99 extern void armada_370_xp_cpu_resume(void);
100 extern void armada_38x_cpu_resume(void);
101
102 static phys_addr_t pmsu_mp_phys_base;
103 static void __iomem *pmsu_mp_base;
104
105 static void *mvebu_cpu_resume;
106
107 static const struct of_device_id of_pmsu_table[] = {
108 { .compatible = "marvell,armada-370-pmsu", },
109 { .compatible = "marvell,armada-370-xp-pmsu", },
110 { .compatible = "marvell,armada-380-pmsu", },
111 { /* end of list */ },
112 };
113
mvebu_pmsu_set_cpu_boot_addr(int hw_cpu,void * boot_addr)114 void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
115 {
116 writel(virt_to_phys(boot_addr), pmsu_mp_base +
117 PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
118 }
119
120 extern unsigned char mvebu_boot_wa_start[];
121 extern unsigned char mvebu_boot_wa_end[];
122
123 /*
124 * This function sets up the boot address workaround needed for SMP
125 * boot on Armada 375 Z1 and cpuidle on Armada 370. It unmaps the
126 * BootROM Mbus window, and instead remaps a crypto SRAM into which a
127 * custom piece of code is copied to replace the problematic BootROM.
128 */
mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,unsigned int crypto_eng_attribute,phys_addr_t resume_addr_reg)129 int mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,
130 unsigned int crypto_eng_attribute,
131 phys_addr_t resume_addr_reg)
132 {
133 void __iomem *sram_virt_base;
134 u32 code_len = mvebu_boot_wa_end - mvebu_boot_wa_start;
135
136 mvebu_mbus_del_window(BOOTROM_BASE, BOOTROM_SIZE);
137 mvebu_mbus_add_window_by_id(crypto_eng_target, crypto_eng_attribute,
138 SRAM_PHYS_BASE, SZ_64K);
139
140 sram_virt_base = ioremap(SRAM_PHYS_BASE, SZ_64K);
141 if (!sram_virt_base) {
142 pr_err("Unable to map SRAM to setup the boot address WA\n");
143 return -ENOMEM;
144 }
145
146 memcpy(sram_virt_base, &mvebu_boot_wa_start, code_len);
147
148 /*
149 * The last word of the code copied in SRAM must contain the
150 * physical base address of the PMSU register. We
151 * intentionally store this address in the native endianness
152 * of the system.
153 */
154 __raw_writel((unsigned long)resume_addr_reg,
155 sram_virt_base + code_len - 4);
156
157 iounmap(sram_virt_base);
158
159 return 0;
160 }
161
mvebu_v7_pmsu_init(void)162 static int __init mvebu_v7_pmsu_init(void)
163 {
164 struct device_node *np;
165 struct resource res;
166 int ret = 0;
167
168 np = of_find_matching_node(NULL, of_pmsu_table);
169 if (!np)
170 return 0;
171
172 pr_info("Initializing Power Management Service Unit\n");
173
174 if (of_address_to_resource(np, 0, &res)) {
175 pr_err("unable to get resource\n");
176 ret = -ENOENT;
177 goto out;
178 }
179
180 if (of_device_is_compatible(np, "marvell,armada-370-xp-pmsu")) {
181 pr_warn(FW_WARN "deprecated pmsu binding\n");
182 res.start = res.start - PMSU_BASE_OFFSET;
183 res.end = res.start + PMSU_REG_SIZE - 1;
184 }
185
186 if (!request_mem_region(res.start, resource_size(&res),
187 np->full_name)) {
188 pr_err("unable to request region\n");
189 ret = -EBUSY;
190 goto out;
191 }
192
193 pmsu_mp_phys_base = res.start;
194
195 pmsu_mp_base = ioremap(res.start, resource_size(&res));
196 if (!pmsu_mp_base) {
197 pr_err("unable to map registers\n");
198 release_mem_region(res.start, resource_size(&res));
199 ret = -ENOMEM;
200 goto out;
201 }
202
203 out:
204 of_node_put(np);
205 return ret;
206 }
207
mvebu_v7_pmsu_enable_l2_powerdown_onidle(void)208 static void mvebu_v7_pmsu_enable_l2_powerdown_onidle(void)
209 {
210 u32 reg;
211
212 if (pmsu_mp_base == NULL)
213 return;
214
215 /* Enable L2 & Fabric powerdown in Deep-Idle mode - Fabric */
216 reg = readl(pmsu_mp_base + L2C_NFABRIC_PM_CTL);
217 reg |= L2C_NFABRIC_PM_CTL_PWR_DOWN;
218 writel(reg, pmsu_mp_base + L2C_NFABRIC_PM_CTL);
219 }
220
221 enum pmsu_idle_prepare_flags {
222 PMSU_PREPARE_NORMAL = 0,
223 PMSU_PREPARE_DEEP_IDLE = BIT(0),
224 PMSU_PREPARE_SNOOP_DISABLE = BIT(1),
225 };
226
227 /* No locking is needed because we only access per-CPU registers */
mvebu_v7_pmsu_idle_prepare(unsigned long flags)228 static int mvebu_v7_pmsu_idle_prepare(unsigned long flags)
229 {
230 unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
231 u32 reg;
232
233 if (pmsu_mp_base == NULL)
234 return -EINVAL;
235
236 /*
237 * Adjust the PMSU configuration to wait for WFI signal, enable
238 * IRQ and FIQ as wakeup events, set wait for snoop queue empty
239 * indication and mask IRQ and FIQ from CPU
240 */
241 reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
242 reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT |
243 PMSU_STATUS_AND_MASK_IRQ_WAKEUP |
244 PMSU_STATUS_AND_MASK_FIQ_WAKEUP |
245 PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT |
246 PMSU_STATUS_AND_MASK_IRQ_MASK |
247 PMSU_STATUS_AND_MASK_FIQ_MASK;
248 writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
249
250 reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
251 /* ask HW to power down the L2 Cache if needed */
252 if (flags & PMSU_PREPARE_DEEP_IDLE)
253 reg |= PMSU_CONTROL_AND_CONFIG_L2_PWDDN;
254
255 /* request power down */
256 reg |= PMSU_CONTROL_AND_CONFIG_PWDDN_REQ;
257 writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
258
259 if (flags & PMSU_PREPARE_SNOOP_DISABLE) {
260 /* Disable snoop disable by HW - SW is taking care of it */
261 reg = readl(pmsu_mp_base + PMSU_CPU_POWER_DOWN_CONTROL(hw_cpu));
262 reg |= PMSU_CPU_POWER_DOWN_DIS_SNP_Q_SKIP;
263 writel(reg, pmsu_mp_base + PMSU_CPU_POWER_DOWN_CONTROL(hw_cpu));
264 }
265
266 return 0;
267 }
268
armada_370_xp_pmsu_idle_enter(unsigned long deepidle)269 int armada_370_xp_pmsu_idle_enter(unsigned long deepidle)
270 {
271 unsigned long flags = PMSU_PREPARE_SNOOP_DISABLE;
272 int ret;
273
274 if (deepidle)
275 flags |= PMSU_PREPARE_DEEP_IDLE;
276
277 ret = mvebu_v7_pmsu_idle_prepare(flags);
278 if (ret)
279 return ret;
280
281 v7_exit_coherency_flush(all);
282
283 ll_disable_coherency();
284
285 dsb();
286
287 wfi();
288
289 /* If we are here, wfi failed. As processors run out of
290 * coherency for some time, tlbs might be stale, so flush them
291 */
292 local_flush_tlb_all();
293
294 ll_enable_coherency();
295
296 /* Test the CR_C bit and set it if it was cleared */
297 asm volatile(
298 "mrc p15, 0, r0, c1, c0, 0 \n\t"
299 "tst r0, %0 \n\t"
300 "orreq r0, r0, #(1 << 2) \n\t"
301 "mcreq p15, 0, r0, c1, c0, 0 \n\t"
302 "isb "
303 : : "Ir" (CR_C) : "r0");
304
305 pr_debug("Failed to suspend the system\n");
306
307 return 0;
308 }
309
armada_370_xp_cpu_suspend(unsigned long deepidle)310 static int armada_370_xp_cpu_suspend(unsigned long deepidle)
311 {
312 return cpu_suspend(deepidle, armada_370_xp_pmsu_idle_enter);
313 }
314
armada_38x_do_cpu_suspend(unsigned long deepidle)315 int armada_38x_do_cpu_suspend(unsigned long deepidle)
316 {
317 unsigned long flags = 0;
318
319 if (deepidle)
320 flags |= PMSU_PREPARE_DEEP_IDLE;
321
322 mvebu_v7_pmsu_idle_prepare(flags);
323 /*
324 * Already flushed cache, but do it again as the outer cache
325 * functions dirty the cache with spinlocks
326 */
327 v7_exit_coherency_flush(louis);
328
329 scu_power_mode(mvebu_get_scu_base(), SCU_PM_POWEROFF);
330
331 cpu_do_idle();
332
333 return 1;
334 }
335
armada_38x_cpu_suspend(unsigned long deepidle)336 static int armada_38x_cpu_suspend(unsigned long deepidle)
337 {
338 return cpu_suspend(false, armada_38x_do_cpu_suspend);
339 }
340
341 /* No locking is needed because we only access per-CPU registers */
mvebu_v7_pmsu_idle_exit(void)342 void mvebu_v7_pmsu_idle_exit(void)
343 {
344 unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
345 u32 reg;
346
347 if (pmsu_mp_base == NULL)
348 return;
349 /* cancel ask HW to power down the L2 Cache if possible */
350 reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
351 reg &= ~PMSU_CONTROL_AND_CONFIG_L2_PWDDN;
352 writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
353
354 /* cancel Enable wakeup events and mask interrupts */
355 reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
356 reg &= ~(PMSU_STATUS_AND_MASK_IRQ_WAKEUP | PMSU_STATUS_AND_MASK_FIQ_WAKEUP);
357 reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
358 reg &= ~PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT;
359 reg &= ~(PMSU_STATUS_AND_MASK_IRQ_MASK | PMSU_STATUS_AND_MASK_FIQ_MASK);
360 writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
361 }
362
mvebu_v7_cpu_pm_notify(struct notifier_block * self,unsigned long action,void * hcpu)363 static int mvebu_v7_cpu_pm_notify(struct notifier_block *self,
364 unsigned long action, void *hcpu)
365 {
366 if (action == CPU_PM_ENTER) {
367 unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
368 mvebu_pmsu_set_cpu_boot_addr(hw_cpu, mvebu_cpu_resume);
369 } else if (action == CPU_PM_EXIT) {
370 mvebu_v7_pmsu_idle_exit();
371 }
372
373 return NOTIFY_OK;
374 }
375
376 static struct notifier_block mvebu_v7_cpu_pm_notifier = {
377 .notifier_call = mvebu_v7_cpu_pm_notify,
378 };
379
380 static struct platform_device mvebu_v7_cpuidle_device;
381
broken_idle(struct device_node * np)382 static int broken_idle(struct device_node *np)
383 {
384 if (of_property_read_bool(np, "broken-idle")) {
385 pr_warn("CPU idle is currently broken: disabling\n");
386 return 1;
387 }
388
389 return 0;
390 }
391
armada_370_cpuidle_init(void)392 static __init int armada_370_cpuidle_init(void)
393 {
394 struct device_node *np;
395 phys_addr_t redirect_reg;
396
397 np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
398 if (!np)
399 return -ENODEV;
400
401 if (broken_idle(np))
402 goto end;
403
404 /*
405 * On Armada 370, there is "a slow exit process from the deep
406 * idle state due to heavy L1/L2 cache cleanup operations
407 * performed by the BootROM software". To avoid this, we
408 * replace the restart code of the bootrom by a a simple jump
409 * to the boot address. Then the code located at this boot
410 * address will take care of the initialization.
411 */
412 redirect_reg = pmsu_mp_phys_base + PMSU_BOOT_ADDR_REDIRECT_OFFSET(0);
413 mvebu_setup_boot_addr_wa(ARMADA_370_CRYPT0_ENG_TARGET,
414 ARMADA_370_CRYPT0_ENG_ATTR,
415 redirect_reg);
416
417 mvebu_cpu_resume = armada_370_xp_cpu_resume;
418 mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
419 mvebu_v7_cpuidle_device.name = "cpuidle-armada-370";
420
421 end:
422 of_node_put(np);
423 return 0;
424 }
425
armada_38x_cpuidle_init(void)426 static __init int armada_38x_cpuidle_init(void)
427 {
428 struct device_node *np;
429 void __iomem *mpsoc_base;
430 u32 reg;
431
432 pr_warn("CPU idle is currently broken on Armada 38x: disabling\n");
433 return 0;
434
435 np = of_find_compatible_node(NULL, NULL,
436 "marvell,armada-380-coherency-fabric");
437 if (!np)
438 return -ENODEV;
439
440 if (broken_idle(np))
441 goto end;
442
443 of_node_put(np);
444
445 np = of_find_compatible_node(NULL, NULL,
446 "marvell,armada-380-mpcore-soc-ctrl");
447 if (!np)
448 return -ENODEV;
449 mpsoc_base = of_iomap(np, 0);
450 BUG_ON(!mpsoc_base);
451
452 /* Set up reset mask when powering down the cpus */
453 reg = readl(mpsoc_base + MPCORE_RESET_CTL);
454 reg |= MPCORE_RESET_CTL_L2;
455 reg |= MPCORE_RESET_CTL_DEBUG;
456 writel(reg, mpsoc_base + MPCORE_RESET_CTL);
457 iounmap(mpsoc_base);
458
459 /* Set up delay */
460 reg = readl(pmsu_mp_base + PMSU_POWERDOWN_DELAY);
461 reg &= ~PMSU_POWERDOWN_DELAY_MASK;
462 reg |= PMSU_DFLT_ARMADA38X_DELAY;
463 reg |= PMSU_POWERDOWN_DELAY_PMU;
464 writel(reg, pmsu_mp_base + PMSU_POWERDOWN_DELAY);
465
466 mvebu_cpu_resume = armada_38x_cpu_resume;
467 mvebu_v7_cpuidle_device.dev.platform_data = armada_38x_cpu_suspend;
468 mvebu_v7_cpuidle_device.name = "cpuidle-armada-38x";
469
470 end:
471 of_node_put(np);
472 return 0;
473 }
474
armada_xp_cpuidle_init(void)475 static __init int armada_xp_cpuidle_init(void)
476 {
477 struct device_node *np;
478
479 np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
480 if (!np)
481 return -ENODEV;
482
483 if (broken_idle(np))
484 goto end;
485
486 mvebu_cpu_resume = armada_370_xp_cpu_resume;
487 mvebu_v7_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
488 mvebu_v7_cpuidle_device.name = "cpuidle-armada-xp";
489
490 end:
491 of_node_put(np);
492 return 0;
493 }
494
mvebu_v7_cpu_pm_init(void)495 static int __init mvebu_v7_cpu_pm_init(void)
496 {
497 struct device_node *np;
498 int ret;
499
500 np = of_find_matching_node(NULL, of_pmsu_table);
501 if (!np)
502 return 0;
503 of_node_put(np);
504
505 /*
506 * Currently the CPU idle support for Armada 38x is broken, as
507 * the CPU hotplug uses some of the CPU idle functions it is
508 * broken too, so let's disable it
509 */
510 if (of_machine_is_compatible("marvell,armada380")) {
511 cpu_hotplug_disable();
512 pr_warn("CPU hotplug support is currently broken on Armada 38x: disabling\n");
513 }
514
515 if (of_machine_is_compatible("marvell,armadaxp"))
516 ret = armada_xp_cpuidle_init();
517 else if (of_machine_is_compatible("marvell,armada370"))
518 ret = armada_370_cpuidle_init();
519 else if (of_machine_is_compatible("marvell,armada380"))
520 ret = armada_38x_cpuidle_init();
521 else
522 return 0;
523
524 if (ret)
525 return ret;
526
527 mvebu_v7_pmsu_enable_l2_powerdown_onidle();
528 if (mvebu_v7_cpuidle_device.name)
529 platform_device_register(&mvebu_v7_cpuidle_device);
530 cpu_pm_register_notifier(&mvebu_v7_cpu_pm_notifier);
531
532 return 0;
533 }
534
535 arch_initcall(mvebu_v7_cpu_pm_init);
536 early_initcall(mvebu_v7_pmsu_init);
537
mvebu_pmsu_dfs_request_local(void * data)538 static void mvebu_pmsu_dfs_request_local(void *data)
539 {
540 u32 reg;
541 u32 cpu = smp_processor_id();
542 unsigned long flags;
543
544 local_irq_save(flags);
545
546 /* Prepare to enter idle */
547 reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
548 reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT |
549 PMSU_STATUS_AND_MASK_IRQ_MASK |
550 PMSU_STATUS_AND_MASK_FIQ_MASK;
551 writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
552
553 /* Request the DFS transition */
554 reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
555 reg |= PMSU_CONTROL_AND_CONFIG_DFS_REQ;
556 writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
557
558 /* The fact of entering idle will trigger the DFS transition */
559 wfi();
560
561 /*
562 * We're back from idle, the DFS transition has completed,
563 * clear the idle wait indication.
564 */
565 reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
566 reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
567 writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
568
569 local_irq_restore(flags);
570 }
571
mvebu_pmsu_dfs_request(int cpu)572 int mvebu_pmsu_dfs_request(int cpu)
573 {
574 unsigned long timeout;
575 int hwcpu = cpu_logical_map(cpu);
576 u32 reg;
577
578 /* Clear any previous DFS DONE event */
579 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
580 reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE;
581 writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
582
583 /* Mask the DFS done interrupt, since we are going to poll */
584 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
585 reg |= PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
586 writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
587
588 /* Trigger the DFS on the appropriate CPU */
589 smp_call_function_single(cpu, mvebu_pmsu_dfs_request_local,
590 NULL, false);
591
592 /* Poll until the DFS done event is generated */
593 timeout = jiffies + HZ;
594 while (time_before(jiffies, timeout)) {
595 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
596 if (reg & PMSU_EVENT_STATUS_AND_MASK_DFS_DONE)
597 break;
598 udelay(10);
599 }
600
601 if (time_after(jiffies, timeout))
602 return -ETIME;
603
604 /* Restore the DFS mask to its original state */
605 reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
606 reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
607 writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
608
609 return 0;
610 }
611
612 struct cpufreq_dt_platform_data cpufreq_dt_pd = {
613 .independent_clocks = true,
614 };
615
armada_xp_pmsu_cpufreq_init(void)616 static int __init armada_xp_pmsu_cpufreq_init(void)
617 {
618 struct device_node *np;
619 struct resource res;
620 int ret, cpu;
621
622 if (!of_machine_is_compatible("marvell,armadaxp"))
623 return 0;
624
625 /*
626 * In order to have proper cpufreq handling, we need to ensure
627 * that the Device Tree description of the CPU clock includes
628 * the definition of the PMU DFS registers. If not, we do not
629 * register the clock notifier and the cpufreq driver. This
630 * piece of code is only for compatibility with old Device
631 * Trees.
632 */
633 np = of_find_compatible_node(NULL, NULL, "marvell,armada-xp-cpu-clock");
634 if (!np)
635 return 0;
636
637 ret = of_address_to_resource(np, 1, &res);
638 if (ret) {
639 pr_warn(FW_WARN "not enabling cpufreq, deprecated armada-xp-cpu-clock binding\n");
640 of_node_put(np);
641 return 0;
642 }
643
644 of_node_put(np);
645
646 /*
647 * For each CPU, this loop registers the operating points
648 * supported (which are the nominal CPU frequency and half of
649 * it), and registers the clock notifier that will take care
650 * of doing the PMSU part of a frequency transition.
651 */
652 for_each_possible_cpu(cpu) {
653 struct device *cpu_dev;
654 struct clk *clk;
655 int ret;
656
657 cpu_dev = get_cpu_device(cpu);
658 if (!cpu_dev) {
659 pr_err("Cannot get CPU %d\n", cpu);
660 continue;
661 }
662
663 clk = clk_get(cpu_dev, 0);
664 if (IS_ERR(clk)) {
665 pr_err("Cannot get clock for CPU %d\n", cpu);
666 return PTR_ERR(clk);
667 }
668
669 /*
670 * In case of a failure of dev_pm_opp_add(), we don't
671 * bother with cleaning up the registered OPP (there's
672 * no function to do so), and simply cancel the
673 * registration of the cpufreq device.
674 */
675 ret = dev_pm_opp_add(cpu_dev, clk_get_rate(clk), 0);
676 if (ret) {
677 clk_put(clk);
678 return ret;
679 }
680
681 ret = dev_pm_opp_add(cpu_dev, clk_get_rate(clk) / 2, 0);
682 if (ret) {
683 clk_put(clk);
684 return ret;
685 }
686 }
687
688 platform_device_register_data(NULL, "cpufreq-dt", -1,
689 &cpufreq_dt_pd, sizeof(cpufreq_dt_pd));
690 return 0;
691 }
692
693 device_initcall(armada_xp_pmsu_cpufreq_init);
694