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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright 2017 NXP
4 * Copyright 2011,2016 Freescale Semiconductor, Inc.
5 * Copyright 2011 Linaro Ltd.
6 */
7
8#include <linux/clk.h>
9#include <linux/hrtimer.h>
10#include <linux/init.h>
11#include <linux/interrupt.h>
12#include <linux/io.h>
13#include <linux/module.h>
14#include <linux/of.h>
15#include <linux/of_address.h>
16#include <linux/of_device.h>
17#include <linux/perf_event.h>
18#include <linux/slab.h>
19
20#include "common.h"
21
22#define MMDC_MAPSR 0x404
23#define BP_MMDC_MAPSR_PSD 0
24#define BP_MMDC_MAPSR_PSS 4
25
26#define MMDC_MDMISC 0x18
27#define BM_MMDC_MDMISC_DDR_TYPE 0x18
28#define BP_MMDC_MDMISC_DDR_TYPE 0x3
29
30#define TOTAL_CYCLES 0x0
31#define BUSY_CYCLES 0x1
32#define READ_ACCESSES 0x2
33#define WRITE_ACCESSES 0x3
34#define READ_BYTES 0x4
35#define WRITE_BYTES 0x5
36
37/* Enables, resets, freezes, overflow profiling*/
38#define DBG_DIS 0x0
39#define DBG_EN 0x1
40#define DBG_RST 0x2
41#define PRF_FRZ 0x4
42#define CYC_OVF 0x8
43#define PROFILE_SEL 0x10
44
45#define MMDC_MADPCR0 0x410
46#define MMDC_MADPCR1 0x414
47#define MMDC_MADPSR0 0x418
48#define MMDC_MADPSR1 0x41C
49#define MMDC_MADPSR2 0x420
50#define MMDC_MADPSR3 0x424
51#define MMDC_MADPSR4 0x428
52#define MMDC_MADPSR5 0x42C
53
54#define MMDC_NUM_COUNTERS 6
55
56#define MMDC_FLAG_PROFILE_SEL 0x1
57#define MMDC_PRF_AXI_ID_CLEAR 0x0
58
59#define to_mmdc_pmu(p) container_of(p, struct mmdc_pmu, pmu)
60
61static int ddr_type;
62
63struct fsl_mmdc_devtype_data {
64 unsigned int flags;
65};
66
67static const struct fsl_mmdc_devtype_data imx6q_data = {
68};
69
70static const struct fsl_mmdc_devtype_data imx6qp_data = {
71 .flags = MMDC_FLAG_PROFILE_SEL,
72};
73
74static const struct of_device_id imx_mmdc_dt_ids[] = {
75 { .compatible = "fsl,imx6q-mmdc", .data = (void *)&imx6q_data},
76 { .compatible = "fsl,imx6qp-mmdc", .data = (void *)&imx6qp_data},
77 { /* sentinel */ }
78};
79
80#ifdef CONFIG_PERF_EVENTS
81
82static enum cpuhp_state cpuhp_mmdc_state;
83static DEFINE_IDA(mmdc_ida);
84
85PMU_EVENT_ATTR_STRING(total-cycles, mmdc_pmu_total_cycles, "event=0x00")
86PMU_EVENT_ATTR_STRING(busy-cycles, mmdc_pmu_busy_cycles, "event=0x01")
87PMU_EVENT_ATTR_STRING(read-accesses, mmdc_pmu_read_accesses, "event=0x02")
88PMU_EVENT_ATTR_STRING(write-accesses, mmdc_pmu_write_accesses, "event=0x03")
89PMU_EVENT_ATTR_STRING(read-bytes, mmdc_pmu_read_bytes, "event=0x04")
90PMU_EVENT_ATTR_STRING(read-bytes.unit, mmdc_pmu_read_bytes_unit, "MB");
91PMU_EVENT_ATTR_STRING(read-bytes.scale, mmdc_pmu_read_bytes_scale, "0.000001");
92PMU_EVENT_ATTR_STRING(write-bytes, mmdc_pmu_write_bytes, "event=0x05")
93PMU_EVENT_ATTR_STRING(write-bytes.unit, mmdc_pmu_write_bytes_unit, "MB");
94PMU_EVENT_ATTR_STRING(write-bytes.scale, mmdc_pmu_write_bytes_scale, "0.000001");
95
96struct mmdc_pmu {
97 struct pmu pmu;
98 void __iomem *mmdc_base;
99 cpumask_t cpu;
100 struct hrtimer hrtimer;
101 unsigned int active_events;
102 struct device *dev;
103 struct perf_event *mmdc_events[MMDC_NUM_COUNTERS];
104 struct hlist_node node;
105 struct fsl_mmdc_devtype_data *devtype_data;
106 struct clk *mmdc_ipg_clk;
107};
108
109/*
110 * Polling period is set to one second, overflow of total-cycles (the fastest
111 * increasing counter) takes ten seconds so one second is safe
112 */
113static unsigned int mmdc_pmu_poll_period_us = 1000000;
114
115module_param_named(pmu_pmu_poll_period_us, mmdc_pmu_poll_period_us, uint,
116 S_IRUGO | S_IWUSR);
117
118static ktime_t mmdc_pmu_timer_period(void)
119{
120 return ns_to_ktime((u64)mmdc_pmu_poll_period_us * 1000);
121}
122
123static ssize_t mmdc_pmu_cpumask_show(struct device *dev,
124 struct device_attribute *attr, char *buf)
125{
126 struct mmdc_pmu *pmu_mmdc = dev_get_drvdata(dev);
127
128 return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu);
129}
130
131static struct device_attribute mmdc_pmu_cpumask_attr =
132 __ATTR(cpumask, S_IRUGO, mmdc_pmu_cpumask_show, NULL);
133
134static struct attribute *mmdc_pmu_cpumask_attrs[] = {
135 &mmdc_pmu_cpumask_attr.attr,
136 NULL,
137};
138
139static struct attribute_group mmdc_pmu_cpumask_attr_group = {
140 .attrs = mmdc_pmu_cpumask_attrs,
141};
142
143static struct attribute *mmdc_pmu_events_attrs[] = {
144 &mmdc_pmu_total_cycles.attr.attr,
145 &mmdc_pmu_busy_cycles.attr.attr,
146 &mmdc_pmu_read_accesses.attr.attr,
147 &mmdc_pmu_write_accesses.attr.attr,
148 &mmdc_pmu_read_bytes.attr.attr,
149 &mmdc_pmu_read_bytes_unit.attr.attr,
150 &mmdc_pmu_read_bytes_scale.attr.attr,
151 &mmdc_pmu_write_bytes.attr.attr,
152 &mmdc_pmu_write_bytes_unit.attr.attr,
153 &mmdc_pmu_write_bytes_scale.attr.attr,
154 NULL,
155};
156
157static struct attribute_group mmdc_pmu_events_attr_group = {
158 .name = "events",
159 .attrs = mmdc_pmu_events_attrs,
160};
161
162PMU_FORMAT_ATTR(event, "config:0-63");
163PMU_FORMAT_ATTR(axi_id, "config1:0-63");
164
165static struct attribute *mmdc_pmu_format_attrs[] = {
166 &format_attr_event.attr,
167 &format_attr_axi_id.attr,
168 NULL,
169};
170
171static struct attribute_group mmdc_pmu_format_attr_group = {
172 .name = "format",
173 .attrs = mmdc_pmu_format_attrs,
174};
175
176static const struct attribute_group *attr_groups[] = {
177 &mmdc_pmu_events_attr_group,
178 &mmdc_pmu_format_attr_group,
179 &mmdc_pmu_cpumask_attr_group,
180 NULL,
181};
182
183static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
184{
185 void __iomem *mmdc_base, *reg;
186
187 mmdc_base = pmu_mmdc->mmdc_base;
188
189 switch (cfg) {
190 case TOTAL_CYCLES:
191 reg = mmdc_base + MMDC_MADPSR0;
192 break;
193 case BUSY_CYCLES:
194 reg = mmdc_base + MMDC_MADPSR1;
195 break;
196 case READ_ACCESSES:
197 reg = mmdc_base + MMDC_MADPSR2;
198 break;
199 case WRITE_ACCESSES:
200 reg = mmdc_base + MMDC_MADPSR3;
201 break;
202 case READ_BYTES:
203 reg = mmdc_base + MMDC_MADPSR4;
204 break;
205 case WRITE_BYTES:
206 reg = mmdc_base + MMDC_MADPSR5;
207 break;
208 default:
209 return WARN_ONCE(1,
210 "invalid configuration %d for mmdc counter", cfg);
211 }
212 return readl(reg);
213}
214
215static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
216{
217 struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
218 int target;
219
220 if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
221 return 0;
222
223 target = cpumask_any_but(cpu_online_mask, cpu);
224 if (target >= nr_cpu_ids)
225 return 0;
226
227 perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
228 cpumask_set_cpu(target, &pmu_mmdc->cpu);
229
230 return 0;
231}
232
233static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
234 struct pmu *pmu,
235 unsigned long *used_counters)
236{
237 int cfg = event->attr.config;
238
239 if (is_software_event(event))
240 return true;
241
242 if (event->pmu != pmu)
243 return false;
244
245 return !test_and_set_bit(cfg, used_counters);
246}
247
248/*
249 * Each event has a single fixed-purpose counter, so we can only have a
250 * single active event for each at any point in time. Here we just check
251 * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
252 * event numbers are valid.
253 */
254static bool mmdc_pmu_group_is_valid(struct perf_event *event)
255{
256 struct pmu *pmu = event->pmu;
257 struct perf_event *leader = event->group_leader;
258 struct perf_event *sibling;
259 unsigned long counter_mask = 0;
260
261 set_bit(leader->attr.config, &counter_mask);
262
263 if (event != leader) {
264 if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
265 return false;
266 }
267
268 for_each_sibling_event(sibling, leader) {
269 if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
270 return false;
271 }
272
273 return true;
274}
275
276static int mmdc_pmu_event_init(struct perf_event *event)
277{
278 struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
279 int cfg = event->attr.config;
280
281 if (event->attr.type != event->pmu->type)
282 return -ENOENT;
283
284 if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
285 return -EOPNOTSUPP;
286
287 if (event->cpu < 0) {
288 dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
289 return -EOPNOTSUPP;
290 }
291
292 if (event->attr.sample_period)
293 return -EINVAL;
294
295 if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
296 return -EINVAL;
297
298 if (!mmdc_pmu_group_is_valid(event))
299 return -EINVAL;
300
301 event->cpu = cpumask_first(&pmu_mmdc->cpu);
302 return 0;
303}
304
305static void mmdc_pmu_event_update(struct perf_event *event)
306{
307 struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
308 struct hw_perf_event *hwc = &event->hw;
309 u64 delta, prev_raw_count, new_raw_count;
310
311 do {
312 prev_raw_count = local64_read(&hwc->prev_count);
313 new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
314 event->attr.config);
315 } while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
316 new_raw_count) != prev_raw_count);
317
318 delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
319
320 local64_add(delta, &event->count);
321}
322
323static void mmdc_pmu_event_start(struct perf_event *event, int flags)
324{
325 struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
326 struct hw_perf_event *hwc = &event->hw;
327 void __iomem *mmdc_base, *reg;
328 u32 val;
329
330 mmdc_base = pmu_mmdc->mmdc_base;
331 reg = mmdc_base + MMDC_MADPCR0;
332
333 /*
334 * hrtimer is required because mmdc does not provide an interrupt so
335 * polling is necessary
336 */
337 hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
338 HRTIMER_MODE_REL_PINNED);
339
340 local64_set(&hwc->prev_count, 0);
341
342 writel(DBG_RST, reg);
343
344 /*
345 * Write the AXI id parameter to MADPCR1.
346 */
347 val = event->attr.config1;
348 reg = mmdc_base + MMDC_MADPCR1;
349 writel(val, reg);
350
351 reg = mmdc_base + MMDC_MADPCR0;
352 val = DBG_EN;
353 if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
354 val |= PROFILE_SEL;
355
356 writel(val, reg);
357}
358
359static int mmdc_pmu_event_add(struct perf_event *event, int flags)
360{
361 struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
362 struct hw_perf_event *hwc = &event->hw;
363
364 int cfg = event->attr.config;
365
366 if (flags & PERF_EF_START)
367 mmdc_pmu_event_start(event, flags);
368
369 if (pmu_mmdc->mmdc_events[cfg] != NULL)
370 return -EAGAIN;
371
372 pmu_mmdc->mmdc_events[cfg] = event;
373 pmu_mmdc->active_events++;
374
375 local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
376
377 return 0;
378}
379
380static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
381{
382 struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
383 void __iomem *mmdc_base, *reg;
384
385 mmdc_base = pmu_mmdc->mmdc_base;
386 reg = mmdc_base + MMDC_MADPCR0;
387
388 writel(PRF_FRZ, reg);
389
390 reg = mmdc_base + MMDC_MADPCR1;
391 writel(MMDC_PRF_AXI_ID_CLEAR, reg);
392
393 mmdc_pmu_event_update(event);
394}
395
396static void mmdc_pmu_event_del(struct perf_event *event, int flags)
397{
398 struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
399 int cfg = event->attr.config;
400
401 pmu_mmdc->mmdc_events[cfg] = NULL;
402 pmu_mmdc->active_events--;
403
404 if (pmu_mmdc->active_events == 0)
405 hrtimer_cancel(&pmu_mmdc->hrtimer);
406
407 mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
408}
409
410static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
411{
412 int i;
413
414 for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
415 struct perf_event *event = pmu_mmdc->mmdc_events[i];
416
417 if (event)
418 mmdc_pmu_event_update(event);
419 }
420}
421
422static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
423{
424 struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
425 hrtimer);
426
427 mmdc_pmu_overflow_handler(pmu_mmdc);
428 hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
429
430 return HRTIMER_RESTART;
431}
432
433static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
434 void __iomem *mmdc_base, struct device *dev)
435{
436 int mmdc_num;
437
438 *pmu_mmdc = (struct mmdc_pmu) {
439 .pmu = (struct pmu) {
440 .task_ctx_nr = perf_invalid_context,
441 .attr_groups = attr_groups,
442 .event_init = mmdc_pmu_event_init,
443 .add = mmdc_pmu_event_add,
444 .del = mmdc_pmu_event_del,
445 .start = mmdc_pmu_event_start,
446 .stop = mmdc_pmu_event_stop,
447 .read = mmdc_pmu_event_update,
448 .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
449 },
450 .mmdc_base = mmdc_base,
451 .dev = dev,
452 .active_events = 0,
453 };
454
455 mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
456
457 return mmdc_num;
458}
459
460static int imx_mmdc_remove(struct platform_device *pdev)
461{
462 struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
463
464 cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
465 perf_pmu_unregister(&pmu_mmdc->pmu);
466 iounmap(pmu_mmdc->mmdc_base);
467 clk_disable_unprepare(pmu_mmdc->mmdc_ipg_clk);
468 kfree(pmu_mmdc);
469 return 0;
470}
471
472static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base,
473 struct clk *mmdc_ipg_clk)
474{
475 struct mmdc_pmu *pmu_mmdc;
476 char *name;
477 int mmdc_num;
478 int ret;
479 const struct of_device_id *of_id =
480 of_match_device(imx_mmdc_dt_ids, &pdev->dev);
481
482 pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
483 if (!pmu_mmdc) {
484 pr_err("failed to allocate PMU device!\n");
485 return -ENOMEM;
486 }
487
488 /* The first instance registers the hotplug state */
489 if (!cpuhp_mmdc_state) {
490 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
491 "perf/arm/mmdc:online", NULL,
492 mmdc_pmu_offline_cpu);
493 if (ret < 0) {
494 pr_err("cpuhp_setup_state_multi failed\n");
495 goto pmu_free;
496 }
497 cpuhp_mmdc_state = ret;
498 }
499
500 mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
501 pmu_mmdc->mmdc_ipg_clk = mmdc_ipg_clk;
502 if (mmdc_num == 0)
503 name = "mmdc";
504 else
505 name = devm_kasprintf(&pdev->dev,
506 GFP_KERNEL, "mmdc%d", mmdc_num);
507
508 pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
509
510 hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
511 HRTIMER_MODE_REL);
512 pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
513
514 cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
515
516 /* Register the pmu instance for cpu hotplug */
517 cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
518
519 ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
520 if (ret)
521 goto pmu_register_err;
522
523 platform_set_drvdata(pdev, pmu_mmdc);
524 return 0;
525
526pmu_register_err:
527 pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
528 cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
529 hrtimer_cancel(&pmu_mmdc->hrtimer);
530pmu_free:
531 kfree(pmu_mmdc);
532 return ret;
533}
534
535#else
536#define imx_mmdc_remove NULL
537#define imx_mmdc_perf_init(pdev, mmdc_base, mmdc_ipg_clk) 0
538#endif
539
540static int imx_mmdc_probe(struct platform_device *pdev)
541{
542 struct device_node *np = pdev->dev.of_node;
543 void __iomem *mmdc_base, *reg;
544 struct clk *mmdc_ipg_clk;
545 u32 val;
546 int err;
547
548 /* the ipg clock is optional */
549 mmdc_ipg_clk = devm_clk_get(&pdev->dev, NULL);
550 if (IS_ERR(mmdc_ipg_clk))
551 mmdc_ipg_clk = NULL;
552
553 err = clk_prepare_enable(mmdc_ipg_clk);
554 if (err) {
555 dev_err(&pdev->dev, "Unable to enable mmdc ipg clock.\n");
556 return err;
557 }
558
559 mmdc_base = of_iomap(np, 0);
560 WARN_ON(!mmdc_base);
561
562 reg = mmdc_base + MMDC_MDMISC;
563 /* Get ddr type */
564 val = readl_relaxed(reg);
565 ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
566 BP_MMDC_MDMISC_DDR_TYPE;
567
568 reg = mmdc_base + MMDC_MAPSR;
569
570 /* Enable automatic power saving */
571 val = readl_relaxed(reg);
572 val &= ~(1 << BP_MMDC_MAPSR_PSD);
573 writel_relaxed(val, reg);
574
575 err = imx_mmdc_perf_init(pdev, mmdc_base, mmdc_ipg_clk);
576 if (err) {
577 iounmap(mmdc_base);
578 clk_disable_unprepare(mmdc_ipg_clk);
579 }
580
581 return err;
582}
583
584int imx_mmdc_get_ddr_type(void)
585{
586 return ddr_type;
587}
588
589static struct platform_driver imx_mmdc_driver = {
590 .driver = {
591 .name = "imx-mmdc",
592 .of_match_table = imx_mmdc_dt_ids,
593 },
594 .probe = imx_mmdc_probe,
595 .remove = imx_mmdc_remove,
596};
597
598static int __init imx_mmdc_init(void)
599{
600 return platform_driver_register(&imx_mmdc_driver);
601}
602postcore_initcall(imx_mmdc_init);
1/*
2 * Copyright 2011 Freescale Semiconductor, Inc.
3 * Copyright 2011 Linaro Ltd.
4 *
5 * The code contained herein is licensed under the GNU General Public
6 * License. You may obtain a copy of the GNU General Public License
7 * Version 2 or later at the following locations:
8 *
9 * http://www.opensource.org/licenses/gpl-license.html
10 * http://www.gnu.org/copyleft/gpl.html
11 */
12
13#include <linux/init.h>
14#include <linux/io.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <linux/of_device.h>
19
20#include "common.h"
21
22#define MMDC_MAPSR 0x404
23#define BP_MMDC_MAPSR_PSD 0
24#define BP_MMDC_MAPSR_PSS 4
25
26#define MMDC_MDMISC 0x18
27#define BM_MMDC_MDMISC_DDR_TYPE 0x18
28#define BP_MMDC_MDMISC_DDR_TYPE 0x3
29
30static int ddr_type;
31
32static int imx_mmdc_probe(struct platform_device *pdev)
33{
34 struct device_node *np = pdev->dev.of_node;
35 void __iomem *mmdc_base, *reg;
36 u32 val;
37 int timeout = 0x400;
38
39 mmdc_base = of_iomap(np, 0);
40 WARN_ON(!mmdc_base);
41
42 reg = mmdc_base + MMDC_MDMISC;
43 /* Get ddr type */
44 val = readl_relaxed(reg);
45 ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
46 BP_MMDC_MDMISC_DDR_TYPE;
47
48 reg = mmdc_base + MMDC_MAPSR;
49
50 /* Enable automatic power saving */
51 val = readl_relaxed(reg);
52 val &= ~(1 << BP_MMDC_MAPSR_PSD);
53 writel_relaxed(val, reg);
54
55 /* Ensure it's successfully enabled */
56 while (!(readl_relaxed(reg) & 1 << BP_MMDC_MAPSR_PSS) && --timeout)
57 cpu_relax();
58
59 if (unlikely(!timeout)) {
60 pr_warn("%s: failed to enable automatic power saving\n",
61 __func__);
62 return -EBUSY;
63 }
64
65 return 0;
66}
67
68int imx_mmdc_get_ddr_type(void)
69{
70 return ddr_type;
71}
72
73static const struct of_device_id imx_mmdc_dt_ids[] = {
74 { .compatible = "fsl,imx6q-mmdc", },
75 { /* sentinel */ }
76};
77
78static struct platform_driver imx_mmdc_driver = {
79 .driver = {
80 .name = "imx-mmdc",
81 .of_match_table = imx_mmdc_dt_ids,
82 },
83 .probe = imx_mmdc_probe,
84};
85
86static int __init imx_mmdc_init(void)
87{
88 return platform_driver_register(&imx_mmdc_driver);
89}
90postcore_initcall(imx_mmdc_init);