1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PolarFire SoC MSS/core complex clock control
4 *
5 * Copyright (C) 2020-2022 Microchip Technology Inc. All rights reserved.
6 */
7#include <linux/auxiliary_bus.h>
8#include <linux/clk-provider.h>
9#include <linux/io.h>
10#include <linux/module.h>
11#include <linux/platform_device.h>
12#include <linux/slab.h>
13#include <dt-bindings/clock/microchip,mpfs-clock.h>
14#include <soc/microchip/mpfs.h>
15
16/* address offset of control registers */
17#define REG_MSSPLL_REF_CR 0x08u
18#define REG_MSSPLL_POSTDIV01_CR 0x10u
19#define REG_MSSPLL_POSTDIV23_CR 0x14u
20#define REG_MSSPLL_SSCG_2_CR 0x2Cu
21#define REG_CLOCK_CONFIG_CR 0x08u
22#define REG_RTC_CLOCK_CR 0x0Cu
23#define REG_SUBBLK_CLOCK_CR 0x84u
24#define REG_SUBBLK_RESET_CR 0x88u
25
26#define MSSPLL_FBDIV_SHIFT 0x00u
27#define MSSPLL_FBDIV_WIDTH 0x0Cu
28#define MSSPLL_REFDIV_SHIFT 0x08u
29#define MSSPLL_REFDIV_WIDTH 0x06u
30#define MSSPLL_POSTDIV02_SHIFT 0x08u
31#define MSSPLL_POSTDIV13_SHIFT 0x18u
32#define MSSPLL_POSTDIV_WIDTH 0x07u
33#define MSSPLL_FIXED_DIV 4u
34
35/*
36 * This clock ID is defined here, rather than the binding headers, as it is an
37 * internal clock only, and therefore has no consumers in other peripheral
38 * blocks.
39 */
40#define CLK_MSSPLL_INTERNAL 38u
41
42struct mpfs_clock_data {
43 struct device *dev;
44 void __iomem *base;
45 void __iomem *msspll_base;
46 struct clk_hw_onecell_data hw_data;
47};
48
49struct mpfs_msspll_hw_clock {
50 void __iomem *base;
51 struct clk_hw hw;
52 struct clk_init_data init;
53 unsigned int id;
54 u32 reg_offset;
55 u32 shift;
56 u32 width;
57 u32 flags;
58};
59
60#define to_mpfs_msspll_clk(_hw) container_of(_hw, struct mpfs_msspll_hw_clock, hw)
61
62struct mpfs_msspll_out_hw_clock {
63 void __iomem *base;
64 struct clk_divider output;
65 struct clk_init_data init;
66 unsigned int id;
67 u32 reg_offset;
68};
69
70#define to_mpfs_msspll_out_clk(_hw) container_of(_hw, struct mpfs_msspll_out_hw_clock, hw)
71
72struct mpfs_cfg_hw_clock {
73 struct clk_divider cfg;
74 struct clk_init_data init;
75 unsigned int id;
76 u32 reg_offset;
77};
78
79struct mpfs_periph_hw_clock {
80 struct clk_gate periph;
81 unsigned int id;
82};
83
84/*
85 * mpfs_clk_lock prevents anything else from writing to the
86 * mpfs clk block while a software locked register is being written.
87 */
88static DEFINE_SPINLOCK(mpfs_clk_lock);
89
90static const struct clk_parent_data mpfs_ext_ref[] = {
91 { .index = 0 },
92};
93
94static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
95 { 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
96 { 0, 0 }
97};
98
99static const struct clk_div_table mpfs_div_ahb_table[] = {
100 { 1, 2 }, { 2, 4}, { 3, 8 },
101 { 0, 0 }
102};
103
104/*
105 * The only two supported reference clock frequencies for the PolarFire SoC are
106 * 100 and 125 MHz, as the rtc reference is required to be 1 MHz.
107 * It therefore only needs to have divider table entries corresponding to
108 * divide by 100 and 125.
109 */
110static const struct clk_div_table mpfs_div_rtcref_table[] = {
111 { 100, 100 }, { 125, 125 },
112 { 0, 0 }
113};
114
115/*
116 * MSS PLL internal clock
117 */
118
119static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned long prate)
120{
121 struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
122 void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
123 void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
124 u32 mult, ref_div;
125
126 mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
127 mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
128 ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
129 ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
130
131 return prate * mult / (ref_div * MSSPLL_FIXED_DIV);
132}
133
134static const struct clk_ops mpfs_clk_msspll_ops = {
135 .recalc_rate = mpfs_clk_msspll_recalc_rate,
136};
137
138#define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) { \
139 .id = _id, \
140 .flags = _flags, \
141 .shift = _shift, \
142 .width = _width, \
143 .reg_offset = _offset, \
144 .hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_msspll_ops, 0), \
145}
146
147static struct mpfs_msspll_hw_clock mpfs_msspll_clks[] = {
148 CLK_PLL(CLK_MSSPLL_INTERNAL, "clk_msspll_internal", mpfs_ext_ref, MSSPLL_FBDIV_SHIFT,
149 MSSPLL_FBDIV_WIDTH, 0, REG_MSSPLL_SSCG_2_CR),
150};
151
152static int mpfs_clk_register_mssplls(struct device *dev, struct mpfs_msspll_hw_clock *msspll_hws,
153 unsigned int num_clks, struct mpfs_clock_data *data)
154{
155 unsigned int i;
156 int ret;
157
158 for (i = 0; i < num_clks; i++) {
159 struct mpfs_msspll_hw_clock *msspll_hw = &msspll_hws[i];
160
161 msspll_hw->base = data->msspll_base;
162 ret = devm_clk_hw_register(dev, hw: &msspll_hw->hw);
163 if (ret)
164 return dev_err_probe(dev, err: ret, fmt: "failed to register msspll id: %d\n",
165 CLK_MSSPLL_INTERNAL);
166
167 data->hw_data.hws[msspll_hw->id] = &msspll_hw->hw;
168 }
169
170 return 0;
171}
172
173/*
174 * MSS PLL output clocks
175 */
176
177#define CLK_PLL_OUT(_id, _name, _parent, _flags, _shift, _width, _offset) { \
178 .id = _id, \
179 .output.shift = _shift, \
180 .output.width = _width, \
181 .output.table = NULL, \
182 .reg_offset = _offset, \
183 .output.flags = _flags, \
184 .output.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0), \
185 .output.lock = &mpfs_clk_lock, \
186}
187
188static struct mpfs_msspll_out_hw_clock mpfs_msspll_out_clks[] = {
189 CLK_PLL_OUT(CLK_MSSPLL0, "clk_msspll", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
190 MSSPLL_POSTDIV02_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV01_CR),
191 CLK_PLL_OUT(CLK_MSSPLL1, "clk_msspll1", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
192 MSSPLL_POSTDIV13_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV01_CR),
193 CLK_PLL_OUT(CLK_MSSPLL2, "clk_msspll2", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
194 MSSPLL_POSTDIV02_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV23_CR),
195 CLK_PLL_OUT(CLK_MSSPLL3, "clk_msspll3", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
196 MSSPLL_POSTDIV13_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV23_CR),
197};
198
199static int mpfs_clk_register_msspll_outs(struct device *dev,
200 struct mpfs_msspll_out_hw_clock *msspll_out_hws,
201 unsigned int num_clks, struct mpfs_clock_data *data)
202{
203 unsigned int i;
204 int ret;
205
206 for (i = 0; i < num_clks; i++) {
207 struct mpfs_msspll_out_hw_clock *msspll_out_hw = &msspll_out_hws[i];
208
209 msspll_out_hw->output.reg = data->msspll_base + msspll_out_hw->reg_offset;
210 ret = devm_clk_hw_register(dev, hw: &msspll_out_hw->output.hw);
211 if (ret)
212 return dev_err_probe(dev, err: ret, fmt: "failed to register msspll out id: %d\n",
213 msspll_out_hw->id);
214
215 data->hw_data.hws[msspll_out_hw->id] = &msspll_out_hw->output.hw;
216 }
217
218 return 0;
219}
220
221/*
222 * "CFG" clocks
223 */
224
225#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags, _offset) { \
226 .id = _id, \
227 .cfg.shift = _shift, \
228 .cfg.width = _width, \
229 .cfg.table = _table, \
230 .reg_offset = _offset, \
231 .cfg.flags = _flags, \
232 .cfg.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0), \
233 .cfg.lock = &mpfs_clk_lock, \
234}
235
236#define CLK_CPU_OFFSET 0u
237#define CLK_AXI_OFFSET 1u
238#define CLK_AHB_OFFSET 2u
239#define CLK_RTCREF_OFFSET 3u
240
241static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
242 CLK_CFG(CLK_CPU, "clk_cpu", "clk_msspll", 0, 2, mpfs_div_cpu_axi_table, 0,
243 REG_CLOCK_CONFIG_CR),
244 CLK_CFG(CLK_AXI, "clk_axi", "clk_msspll", 2, 2, mpfs_div_cpu_axi_table, 0,
245 REG_CLOCK_CONFIG_CR),
246 CLK_CFG(CLK_AHB, "clk_ahb", "clk_msspll", 4, 2, mpfs_div_ahb_table, 0,
247 REG_CLOCK_CONFIG_CR),
248 {
249 .id = CLK_RTCREF,
250 .cfg.shift = 0,
251 .cfg.width = 12,
252 .cfg.table = mpfs_div_rtcref_table,
253 .reg_offset = REG_RTC_CLOCK_CR,
254 .cfg.flags = CLK_DIVIDER_ONE_BASED,
255 .cfg.hw.init =
256 CLK_HW_INIT_PARENTS_DATA("clk_rtcref", mpfs_ext_ref, &clk_divider_ops, 0),
257 }
258};
259
260static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
261 unsigned int num_clks, struct mpfs_clock_data *data)
262{
263 unsigned int i, id;
264 int ret;
265
266 for (i = 0; i < num_clks; i++) {
267 struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
268
269 cfg_hw->cfg.reg = data->base + cfg_hw->reg_offset;
270 ret = devm_clk_hw_register(dev, hw: &cfg_hw->cfg.hw);
271 if (ret)
272 return dev_err_probe(dev, err: ret, fmt: "failed to register clock id: %d\n",
273 cfg_hw->id);
274
275 id = cfg_hw->id;
276 data->hw_data.hws[id] = &cfg_hw->cfg.hw;
277 }
278
279 return 0;
280}
281
282/*
283 * peripheral clocks - devices connected to axi or ahb buses.
284 */
285
286#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) { \
287 .id = _id, \
288 .periph.bit_idx = _shift, \
289 .periph.hw.init = CLK_HW_INIT_HW(_name, _parent, &clk_gate_ops, \
290 _flags), \
291 .periph.lock = &mpfs_clk_lock, \
292}
293
294#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT##_OFFSET].cfg.hw)
295
296/*
297 * Critical clocks:
298 * - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
299 * trap handler
300 * - CLK_MMUART0: reserved by the hss
301 * - CLK_DDRC: provides clock to the ddr subsystem
302 * - CLK_RTC: the onboard RTC's AHB bus clock must be kept running as the rtc will stop
303 * if the AHB interface clock is disabled
304 * - CLK_FICx: these provide the processor side clocks to the "FIC" (Fabric InterConnect)
305 * clock domain crossers which provide the interface to the FPGA fabric. Disabling them
306 * causes the FPGA fabric to go into reset.
307 * - CLK_ATHENA: The athena clock is FIC4, which is reserved for the Athena TeraFire.
308 */
309
310static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
311 CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
312 CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
313 CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
314 CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
315 CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(RTCREF), 4, 0),
316 CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
317 CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
318 CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
319 CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
320 CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
321 CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
322 CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
323 CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
324 CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
325 CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
326 CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
327 CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
328 CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, CLK_IS_CRITICAL),
329 CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
330 CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
331 CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
332 CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
333 CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
334 CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AXI), 24, CLK_IS_CRITICAL),
335 CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AXI), 25, CLK_IS_CRITICAL),
336 CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AXI), 26, CLK_IS_CRITICAL),
337 CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AXI), 27, CLK_IS_CRITICAL),
338 CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AXI), 28, CLK_IS_CRITICAL),
339 CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
340};
341
342static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
343 int num_clks, struct mpfs_clock_data *data)
344{
345 unsigned int i, id;
346 int ret;
347
348 for (i = 0; i < num_clks; i++) {
349 struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];
350
351 periph_hw->periph.reg = data->base + REG_SUBBLK_CLOCK_CR;
352 ret = devm_clk_hw_register(dev, hw: &periph_hw->periph.hw);
353 if (ret)
354 return dev_err_probe(dev, err: ret, fmt: "failed to register clock id: %d\n",
355 periph_hw->id);
356
357 id = periph_hws[i].id;
358 data->hw_data.hws[id] = &periph_hw->periph.hw;
359 }
360
361 return 0;
362}
363
364/*
365 * Peripheral clock resets
366 */
367
368#if IS_ENABLED(CONFIG_RESET_CONTROLLER)
369
370u32 mpfs_reset_read(struct device *dev)
371{
372 struct mpfs_clock_data *clock_data = dev_get_drvdata(dev: dev->parent);
373
374 return readl_relaxed(clock_data->base + REG_SUBBLK_RESET_CR);
375}
376EXPORT_SYMBOL_NS_GPL(mpfs_reset_read, MCHP_CLK_MPFS);
377
378void mpfs_reset_write(struct device *dev, u32 val)
379{
380 struct mpfs_clock_data *clock_data = dev_get_drvdata(dev: dev->parent);
381
382 writel_relaxed(val, clock_data->base + REG_SUBBLK_RESET_CR);
383}
384EXPORT_SYMBOL_NS_GPL(mpfs_reset_write, MCHP_CLK_MPFS);
385
386static void mpfs_reset_unregister_adev(void *_adev)
387{
388 struct auxiliary_device *adev = _adev;
389
390 auxiliary_device_delete(auxdev: adev);
391 auxiliary_device_uninit(auxdev: adev);
392}
393
394static void mpfs_reset_adev_release(struct device *dev)
395{
396 struct auxiliary_device *adev = to_auxiliary_dev(dev);
397
398 kfree(objp: adev);
399}
400
401static struct auxiliary_device *mpfs_reset_adev_alloc(struct mpfs_clock_data *clk_data)
402{
403 struct auxiliary_device *adev;
404 int ret;
405
406 adev = kzalloc(size: sizeof(*adev), GFP_KERNEL);
407 if (!adev)
408 return ERR_PTR(error: -ENOMEM);
409
410 adev->name = "reset-mpfs";
411 adev->dev.parent = clk_data->dev;
412 adev->dev.release = mpfs_reset_adev_release;
413 adev->id = 666u;
414
415 ret = auxiliary_device_init(auxdev: adev);
416 if (ret) {
417 kfree(objp: adev);
418 return ERR_PTR(error: ret);
419 }
420
421 return adev;
422}
423
424static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
425{
426 struct auxiliary_device *adev;
427 int ret;
428
429 adev = mpfs_reset_adev_alloc(clk_data);
430 if (IS_ERR(ptr: adev))
431 return PTR_ERR(ptr: adev);
432
433 ret = auxiliary_device_add(adev);
434 if (ret) {
435 auxiliary_device_uninit(auxdev: adev);
436 return ret;
437 }
438
439 return devm_add_action_or_reset(clk_data->dev, mpfs_reset_unregister_adev, adev);
440}
441
442#else /* !CONFIG_RESET_CONTROLLER */
443
444static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
445{
446 return 0;
447}
448
449#endif /* !CONFIG_RESET_CONTROLLER */
450
451static int mpfs_clk_probe(struct platform_device *pdev)
452{
453 struct device *dev = &pdev->dev;
454 struct mpfs_clock_data *clk_data;
455 unsigned int num_clks;
456 int ret;
457
458 /* CLK_RESERVED is not part of clock arrays, so add 1 */
459 num_clks = ARRAY_SIZE(mpfs_msspll_clks) + ARRAY_SIZE(mpfs_msspll_out_clks)
460 + ARRAY_SIZE(mpfs_cfg_clks) + ARRAY_SIZE(mpfs_periph_clks) + 1;
461
462 clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
463 if (!clk_data)
464 return -ENOMEM;
465
466 clk_data->base = devm_platform_ioremap_resource(pdev, index: 0);
467 if (IS_ERR(ptr: clk_data->base))
468 return PTR_ERR(ptr: clk_data->base);
469
470 clk_data->msspll_base = devm_platform_ioremap_resource(pdev, index: 1);
471 if (IS_ERR(ptr: clk_data->msspll_base))
472 return PTR_ERR(ptr: clk_data->msspll_base);
473
474 clk_data->hw_data.num = num_clks;
475 clk_data->dev = dev;
476 dev_set_drvdata(dev, data: clk_data);
477
478 ret = mpfs_clk_register_mssplls(dev, msspll_hws: mpfs_msspll_clks, ARRAY_SIZE(mpfs_msspll_clks),
479 data: clk_data);
480 if (ret)
481 return ret;
482
483 ret = mpfs_clk_register_msspll_outs(dev, msspll_out_hws: mpfs_msspll_out_clks,
484 ARRAY_SIZE(mpfs_msspll_out_clks),
485 data: clk_data);
486 if (ret)
487 return ret;
488
489 ret = mpfs_clk_register_cfgs(dev, cfg_hws: mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), data: clk_data);
490 if (ret)
491 return ret;
492
493 ret = mpfs_clk_register_periphs(dev, periph_hws: mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
494 data: clk_data);
495 if (ret)
496 return ret;
497
498 ret = devm_of_clk_add_hw_provider(dev, get: of_clk_hw_onecell_get, data: &clk_data->hw_data);
499 if (ret)
500 return ret;
501
502 return mpfs_reset_controller_register(clk_data);
503}
504
505static const struct of_device_id mpfs_clk_of_match_table[] = {
506 { .compatible = "microchip,mpfs-clkcfg", },
507 {}
508};
509MODULE_DEVICE_TABLE(of, mpfs_clk_of_match_table);
510
511static struct platform_driver mpfs_clk_driver = {
512 .probe = mpfs_clk_probe,
513 .driver = {
514 .name = "microchip-mpfs-clkcfg",
515 .of_match_table = mpfs_clk_of_match_table,
516 },
517};
518
519static int __init clk_mpfs_init(void)
520{
521 return platform_driver_register(&mpfs_clk_driver);
522}
523core_initcall(clk_mpfs_init);
524
525static void __exit clk_mpfs_exit(void)
526{
527 platform_driver_unregister(&mpfs_clk_driver);
528}
529module_exit(clk_mpfs_exit);
530
531MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
532MODULE_AUTHOR("Padmarao Begari <padmarao.begari@microchip.com>");
533MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
534MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
535

source code of linux/drivers/clk/microchip/clk-mpfs.c