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