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v6.2
  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_POSTDIV_CR	0x10u
 
 19#define REG_MSSPLL_SSCG_2_CR	0x2Cu
 20#define REG_CLOCK_CONFIG_CR	0x08u
 21#define REG_RTC_CLOCK_CR	0x0Cu
 22#define REG_SUBBLK_CLOCK_CR	0x84u
 23#define REG_SUBBLK_RESET_CR	0x88u
 24
 25#define MSSPLL_FBDIV_SHIFT	0x00u
 26#define MSSPLL_FBDIV_WIDTH	0x0Cu
 27#define MSSPLL_REFDIV_SHIFT	0x08u
 28#define MSSPLL_REFDIV_WIDTH	0x06u
 29#define MSSPLL_POSTDIV_SHIFT	0x08u
 
 30#define MSSPLL_POSTDIV_WIDTH	0x07u
 31#define MSSPLL_FIXED_DIV	4u
 32
 
 
 
 
 
 
 
 33struct mpfs_clock_data {
 34	struct device *dev;
 35	void __iomem *base;
 36	void __iomem *msspll_base;
 37	struct clk_hw_onecell_data hw_data;
 38};
 39
 40struct mpfs_msspll_hw_clock {
 41	void __iomem *base;
 
 
 42	unsigned int id;
 43	u32 reg_offset;
 44	u32 shift;
 45	u32 width;
 46	u32 flags;
 47	struct clk_hw hw;
 48	struct clk_init_data init;
 49};
 50
 51#define to_mpfs_msspll_clk(_hw) container_of(_hw, struct mpfs_msspll_hw_clock, hw)
 52
 
 
 
 
 
 
 
 
 
 
 53struct mpfs_cfg_hw_clock {
 54	struct clk_divider cfg;
 55	struct clk_init_data init;
 56	unsigned int id;
 57	u32 reg_offset;
 58};
 59
 60struct mpfs_periph_hw_clock {
 61	struct clk_gate periph;
 62	unsigned int id;
 63};
 64
 65/*
 66 * mpfs_clk_lock prevents anything else from writing to the
 67 * mpfs clk block while a software locked register is being written.
 68 */
 69static DEFINE_SPINLOCK(mpfs_clk_lock);
 70
 71static const struct clk_parent_data mpfs_ext_ref[] = {
 72	{ .index = 0 },
 73};
 74
 75static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
 76	{ 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
 77	{ 0, 0 }
 78};
 79
 80static const struct clk_div_table mpfs_div_ahb_table[] = {
 81	{ 1, 2 }, { 2, 4}, { 3, 8 },
 82	{ 0, 0 }
 83};
 84
 85/*
 86 * The only two supported reference clock frequencies for the PolarFire SoC are
 87 * 100 and 125 MHz, as the rtc reference is required to be 1 MHz.
 88 * It therefore only needs to have divider table entries corresponding to
 89 * divide by 100 and 125.
 90 */
 91static const struct clk_div_table mpfs_div_rtcref_table[] = {
 92	{ 100, 100 }, { 125, 125 },
 93	{ 0, 0 }
 94};
 95
 96static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned long prate)
 97{
 98	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
 99	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
100	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
101	void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
102	u32 mult, ref_div, postdiv;
103
104	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
105	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
106	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
107	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
108	postdiv = readl_relaxed(postdiv_addr) >> MSSPLL_POSTDIV_SHIFT;
109	postdiv &= clk_div_mask(MSSPLL_POSTDIV_WIDTH);
110
111	return prate * mult / (ref_div * MSSPLL_FIXED_DIV * postdiv);
112}
113
114static long mpfs_clk_msspll_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate)
115{
116	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
117	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
118	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
119	u32 mult, ref_div;
120	unsigned long rate_before_ctrl;
121
122	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
123	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
124	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
125	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
126
127	rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;
128
129	return divider_round_rate(hw, rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
130				  msspll_hw->flags);
131}
132
133static int mpfs_clk_msspll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
134{
135	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
136	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
137	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
138	void __iomem *postdiv_addr = msspll_hw->base + REG_MSSPLL_POSTDIV_CR;
139	u32 mult, ref_div, postdiv;
140	int divider_setting;
141	unsigned long rate_before_ctrl, flags;
142
143	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
144	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
145	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
146	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
147
148	rate_before_ctrl = rate * (ref_div * MSSPLL_FIXED_DIV) / mult;
149	divider_setting = divider_get_val(rate_before_ctrl, prate, NULL, MSSPLL_POSTDIV_WIDTH,
150					  msspll_hw->flags);
151
152	if (divider_setting < 0)
153		return divider_setting;
154
155	spin_lock_irqsave(&mpfs_clk_lock, flags);
156
157	postdiv = readl_relaxed(postdiv_addr);
158	postdiv &= ~(clk_div_mask(MSSPLL_POSTDIV_WIDTH) << MSSPLL_POSTDIV_SHIFT);
159	writel_relaxed(postdiv, postdiv_addr);
160
161	spin_unlock_irqrestore(&mpfs_clk_lock, flags);
162
163	return 0;
164}
165
166static const struct clk_ops mpfs_clk_msspll_ops = {
167	.recalc_rate = mpfs_clk_msspll_recalc_rate,
168	.round_rate = mpfs_clk_msspll_round_rate,
169	.set_rate = mpfs_clk_msspll_set_rate,
170};
171
172#define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) {			\
173	.id = _id,									\
 
174	.shift = _shift,								\
175	.width = _width,								\
176	.reg_offset = _offset,								\
177	.flags = _flags,								\
178	.hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_msspll_ops, 0),	\
179}
180
181static struct mpfs_msspll_hw_clock mpfs_msspll_clks[] = {
182	CLK_PLL(CLK_MSSPLL, "clk_msspll", mpfs_ext_ref, MSSPLL_FBDIV_SHIFT,
183		MSSPLL_FBDIV_WIDTH, 0, REG_MSSPLL_SSCG_2_CR),
184};
185
186static int mpfs_clk_register_mssplls(struct device *dev, struct mpfs_msspll_hw_clock *msspll_hws,
187				     unsigned int num_clks, struct mpfs_clock_data *data)
188{
189	unsigned int i;
190	int ret;
191
192	for (i = 0; i < num_clks; i++) {
193		struct mpfs_msspll_hw_clock *msspll_hw = &msspll_hws[i];
194
195		msspll_hw->base = data->msspll_base;
196		ret = devm_clk_hw_register(dev, &msspll_hw->hw);
197		if (ret)
198			return dev_err_probe(dev, ret, "failed to register msspll id: %d\n",
199					     CLK_MSSPLL);
200
201		data->hw_data.hws[msspll_hw->id] = &msspll_hw->hw;
202	}
203
204	return 0;
205}
206
207/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
208 * "CFG" clocks
209 */
210
211#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags, _offset) {		\
212	.id = _id,									\
213	.cfg.shift = _shift,								\
214	.cfg.width = _width,								\
215	.cfg.table = _table,								\
216	.reg_offset = _offset,								\
217	.cfg.flags = _flags,								\
218	.cfg.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0),		\
219	.cfg.lock = &mpfs_clk_lock,							\
220}
221
222#define CLK_CPU_OFFSET		0u
223#define CLK_AXI_OFFSET		1u
224#define CLK_AHB_OFFSET		2u
225#define CLK_RTCREF_OFFSET	3u
226
227static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
228	CLK_CFG(CLK_CPU, "clk_cpu", "clk_msspll", 0, 2, mpfs_div_cpu_axi_table, 0,
229		REG_CLOCK_CONFIG_CR),
230	CLK_CFG(CLK_AXI, "clk_axi", "clk_msspll", 2, 2, mpfs_div_cpu_axi_table, 0,
231		REG_CLOCK_CONFIG_CR),
232	CLK_CFG(CLK_AHB, "clk_ahb", "clk_msspll", 4, 2, mpfs_div_ahb_table, 0,
233		REG_CLOCK_CONFIG_CR),
234	{
235		.id = CLK_RTCREF,
236		.cfg.shift = 0,
237		.cfg.width = 12,
238		.cfg.table = mpfs_div_rtcref_table,
239		.reg_offset = REG_RTC_CLOCK_CR,
240		.cfg.flags = CLK_DIVIDER_ONE_BASED,
241		.cfg.hw.init =
242			CLK_HW_INIT_PARENTS_DATA("clk_rtcref", mpfs_ext_ref, &clk_divider_ops, 0),
243	}
244};
245
246static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
247				  unsigned int num_clks, struct mpfs_clock_data *data)
248{
249	unsigned int i, id;
250	int ret;
251
252	for (i = 0; i < num_clks; i++) {
253		struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
254
255		cfg_hw->cfg.reg = data->base + cfg_hw->reg_offset;
256		ret = devm_clk_hw_register(dev, &cfg_hw->cfg.hw);
257		if (ret)
258			return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
259					     cfg_hw->id);
260
261		id = cfg_hw->id;
262		data->hw_data.hws[id] = &cfg_hw->cfg.hw;
263	}
264
265	return 0;
266}
267
268/*
269 * peripheral clocks - devices connected to axi or ahb buses.
270 */
271
272#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) {			\
273	.id = _id,								\
274	.periph.bit_idx = _shift,						\
275	.periph.hw.init = CLK_HW_INIT_HW(_name, _parent, &clk_gate_ops,		\
276				  _flags),					\
277	.periph.lock = &mpfs_clk_lock,						\
278}
279
280#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT##_OFFSET].cfg.hw)
281
282/*
283 * Critical clocks:
284 * - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
285 *   trap handler
286 * - CLK_MMUART0: reserved by the hss
287 * - CLK_DDRC: provides clock to the ddr subsystem
288 * - CLK_RTC: the onboard RTC's AHB bus clock must be kept running as the rtc will stop
289 *   if the AHB interface clock is disabled
290 * - CLK_FICx: these provide the processor side clocks to the "FIC" (Fabric InterConnect)
291 *   clock domain crossers which provide the interface to the FPGA fabric. Disabling them
292 *   causes the FPGA fabric to go into reset.
293 * - CLK_ATHENA: The athena clock is FIC4, which is reserved for the Athena TeraFire.
294 */
295
296static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
297	CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
298	CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
299	CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
300	CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
301	CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(RTCREF), 4, 0),
302	CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
303	CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
304	CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
305	CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
306	CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
307	CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
308	CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
309	CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
310	CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
311	CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
312	CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
313	CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
314	CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, CLK_IS_CRITICAL),
315	CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
316	CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
317	CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
318	CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
319	CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
320	CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AXI), 24, CLK_IS_CRITICAL),
321	CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AXI), 25, CLK_IS_CRITICAL),
322	CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AXI), 26, CLK_IS_CRITICAL),
323	CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AXI), 27, CLK_IS_CRITICAL),
324	CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AXI), 28, CLK_IS_CRITICAL),
325	CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
326};
327
328static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
329				     int num_clks, struct mpfs_clock_data *data)
330{
331	unsigned int i, id;
332	int ret;
333
334	for (i = 0; i < num_clks; i++) {
335		struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];
336
337		periph_hw->periph.reg = data->base + REG_SUBBLK_CLOCK_CR;
338		ret = devm_clk_hw_register(dev, &periph_hw->periph.hw);
339		if (ret)
340			return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
341					     periph_hw->id);
342
343		id = periph_hws[i].id;
344		data->hw_data.hws[id] = &periph_hw->periph.hw;
345	}
346
347	return 0;
348}
349
350/*
351 * Peripheral clock resets
352 */
353
354#if IS_ENABLED(CONFIG_RESET_CONTROLLER)
355
356u32 mpfs_reset_read(struct device *dev)
357{
358	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);
359
360	return readl_relaxed(clock_data->base + REG_SUBBLK_RESET_CR);
361}
362EXPORT_SYMBOL_NS_GPL(mpfs_reset_read, MCHP_CLK_MPFS);
363
364void mpfs_reset_write(struct device *dev, u32 val)
365{
366	struct mpfs_clock_data *clock_data = dev_get_drvdata(dev->parent);
367
368	writel_relaxed(val, clock_data->base + REG_SUBBLK_RESET_CR);
369}
370EXPORT_SYMBOL_NS_GPL(mpfs_reset_write, MCHP_CLK_MPFS);
371
372static void mpfs_reset_unregister_adev(void *_adev)
373{
374	struct auxiliary_device *adev = _adev;
375
376	auxiliary_device_delete(adev);
377}
378
379static void mpfs_reset_adev_release(struct device *dev)
380{
381	struct auxiliary_device *adev = to_auxiliary_dev(dev);
382
383	auxiliary_device_uninit(adev);
384
385	kfree(adev);
386}
387
388static struct auxiliary_device *mpfs_reset_adev_alloc(struct mpfs_clock_data *clk_data)
389{
390	struct auxiliary_device *adev;
391	int ret;
392
393	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
394	if (!adev)
395		return ERR_PTR(-ENOMEM);
396
397	adev->name = "reset-mpfs";
398	adev->dev.parent = clk_data->dev;
399	adev->dev.release = mpfs_reset_adev_release;
400	adev->id = 666u;
401
402	ret = auxiliary_device_init(adev);
403	if (ret) {
404		kfree(adev);
405		return ERR_PTR(ret);
406	}
407
408	return adev;
409}
410
411static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
412{
413	struct auxiliary_device *adev;
414	int ret;
415
416	adev = mpfs_reset_adev_alloc(clk_data);
417	if (IS_ERR(adev))
418		return PTR_ERR(adev);
419
420	ret = auxiliary_device_add(adev);
421	if (ret) {
422		auxiliary_device_uninit(adev);
423		return ret;
424	}
425
426	return devm_add_action_or_reset(clk_data->dev, mpfs_reset_unregister_adev, adev);
427}
428
429#else /* !CONFIG_RESET_CONTROLLER */
430
431static int mpfs_reset_controller_register(struct mpfs_clock_data *clk_data)
432{
433	return 0;
434}
435
436#endif /* !CONFIG_RESET_CONTROLLER */
437
438static int mpfs_clk_probe(struct platform_device *pdev)
439{
440	struct device *dev = &pdev->dev;
441	struct mpfs_clock_data *clk_data;
442	unsigned int num_clks;
443	int ret;
444
445	/* CLK_RESERVED is not part of clock arrays, so add 1 */
446	num_clks = ARRAY_SIZE(mpfs_msspll_clks) + ARRAY_SIZE(mpfs_cfg_clks)
447		   + ARRAY_SIZE(mpfs_periph_clks) + 1;
448
449	clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
450	if (!clk_data)
451		return -ENOMEM;
452
453	clk_data->base = devm_platform_ioremap_resource(pdev, 0);
454	if (IS_ERR(clk_data->base))
455		return PTR_ERR(clk_data->base);
456
457	clk_data->msspll_base = devm_platform_ioremap_resource(pdev, 1);
458	if (IS_ERR(clk_data->msspll_base))
459		return PTR_ERR(clk_data->msspll_base);
460
461	clk_data->hw_data.num = num_clks;
462	clk_data->dev = dev;
463	dev_set_drvdata(dev, clk_data);
464
465	ret = mpfs_clk_register_mssplls(dev, mpfs_msspll_clks, ARRAY_SIZE(mpfs_msspll_clks),
466					clk_data);
467	if (ret)
468		return ret;
469
 
 
 
 
 
 
470	ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
471	if (ret)
472		return ret;
473
474	ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
475					clk_data);
476	if (ret)
477		return ret;
478
479	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
480	if (ret)
481		return ret;
482
483	return mpfs_reset_controller_register(clk_data);
484}
485
486static const struct of_device_id mpfs_clk_of_match_table[] = {
487	{ .compatible = "microchip,mpfs-clkcfg", },
488	{}
489};
490MODULE_DEVICE_TABLE(of, mpfs_clk_of_match_table);
491
492static struct platform_driver mpfs_clk_driver = {
493	.probe = mpfs_clk_probe,
494	.driver	= {
495		.name = "microchip-mpfs-clkcfg",
496		.of_match_table = mpfs_clk_of_match_table,
497	},
498};
499
500static int __init clk_mpfs_init(void)
501{
502	return platform_driver_register(&mpfs_clk_driver);
503}
504core_initcall(clk_mpfs_init);
505
506static void __exit clk_mpfs_exit(void)
507{
508	platform_driver_unregister(&mpfs_clk_driver);
509}
510module_exit(clk_mpfs_exit);
511
512MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
513MODULE_AUTHOR("Padmarao Begari <padmarao.begari@microchip.com>");
514MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
515MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
516MODULE_LICENSE("GPL");
v6.13.7
  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/clk-provider.h>
  8#include <linux/io.h>
  9#include <linux/module.h>
 10#include <linux/platform_device.h>
 
 11#include <dt-bindings/clock/microchip,mpfs-clock.h>
 12#include <soc/microchip/mpfs.h>
 13
 14/* address offset of control registers */
 15#define REG_MSSPLL_REF_CR	0x08u
 16#define REG_MSSPLL_POSTDIV01_CR	0x10u
 17#define REG_MSSPLL_POSTDIV23_CR	0x14u
 18#define REG_MSSPLL_SSCG_2_CR	0x2Cu
 19#define REG_CLOCK_CONFIG_CR	0x08u
 20#define REG_RTC_CLOCK_CR	0x0Cu
 21#define REG_SUBBLK_CLOCK_CR	0x84u
 22#define REG_SUBBLK_RESET_CR	0x88u
 23
 24#define MSSPLL_FBDIV_SHIFT	0x00u
 25#define MSSPLL_FBDIV_WIDTH	0x0Cu
 26#define MSSPLL_REFDIV_SHIFT	0x08u
 27#define MSSPLL_REFDIV_WIDTH	0x06u
 28#define MSSPLL_POSTDIV02_SHIFT	0x08u
 29#define MSSPLL_POSTDIV13_SHIFT	0x18u
 30#define MSSPLL_POSTDIV_WIDTH	0x07u
 31#define MSSPLL_FIXED_DIV	4u
 32
 33/*
 34 * This clock ID is defined here, rather than the binding headers, as it is an
 35 * internal clock only, and therefore has no consumers in other peripheral
 36 * blocks.
 37 */
 38#define CLK_MSSPLL_INTERNAL	38u
 39
 40struct mpfs_clock_data {
 41	struct device *dev;
 42	void __iomem *base;
 43	void __iomem *msspll_base;
 44	struct clk_hw_onecell_data hw_data;
 45};
 46
 47struct mpfs_msspll_hw_clock {
 48	void __iomem *base;
 49	struct clk_hw hw;
 50	struct clk_init_data init;
 51	unsigned int id;
 52	u32 reg_offset;
 53	u32 shift;
 54	u32 width;
 55	u32 flags;
 
 
 56};
 57
 58#define to_mpfs_msspll_clk(_hw) container_of(_hw, struct mpfs_msspll_hw_clock, hw)
 59
 60struct mpfs_msspll_out_hw_clock {
 61	void __iomem *base;
 62	struct clk_divider output;
 63	struct clk_init_data init;
 64	unsigned int id;
 65	u32 reg_offset;
 66};
 67
 68#define to_mpfs_msspll_out_clk(_hw) container_of(_hw, struct mpfs_msspll_out_hw_clock, hw)
 69
 70struct mpfs_cfg_hw_clock {
 71	struct clk_divider cfg;
 72	struct clk_init_data init;
 73	unsigned int id;
 74	u32 reg_offset;
 75};
 76
 77struct mpfs_periph_hw_clock {
 78	struct clk_gate periph;
 79	unsigned int id;
 80};
 81
 82/*
 83 * mpfs_clk_lock prevents anything else from writing to the
 84 * mpfs clk block while a software locked register is being written.
 85 */
 86static DEFINE_SPINLOCK(mpfs_clk_lock);
 87
 88static const struct clk_parent_data mpfs_ext_ref[] = {
 89	{ .index = 0 },
 90};
 91
 92static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
 93	{ 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
 94	{ 0, 0 }
 95};
 96
 97static const struct clk_div_table mpfs_div_ahb_table[] = {
 98	{ 1, 2 }, { 2, 4}, { 3, 8 },
 99	{ 0, 0 }
100};
101
102/*
103 * The only two supported reference clock frequencies for the PolarFire SoC are
104 * 100 and 125 MHz, as the rtc reference is required to be 1 MHz.
105 * It therefore only needs to have divider table entries corresponding to
106 * divide by 100 and 125.
107 */
108static const struct clk_div_table mpfs_div_rtcref_table[] = {
109	{ 100, 100 }, { 125, 125 },
110	{ 0, 0 }
111};
112
113/*
114 * MSS PLL internal clock
115 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
116
117static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned long prate)
118{
119	struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
120	void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
121	void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
122	u32 mult, ref_div;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
123
124	mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
125	mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
126	ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
127	ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);
128
129	return prate * mult / (ref_div * MSSPLL_FIXED_DIV);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
130}
131
132static const struct clk_ops mpfs_clk_msspll_ops = {
133	.recalc_rate = mpfs_clk_msspll_recalc_rate,
 
 
134};
135
136#define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) {			\
137	.id = _id,									\
138	.flags = _flags,								\
139	.shift = _shift,								\
140	.width = _width,								\
141	.reg_offset = _offset,								\
 
142	.hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_msspll_ops, 0),	\
143}
144
145static struct mpfs_msspll_hw_clock mpfs_msspll_clks[] = {
146	CLK_PLL(CLK_MSSPLL_INTERNAL, "clk_msspll_internal", mpfs_ext_ref, MSSPLL_FBDIV_SHIFT,
147		MSSPLL_FBDIV_WIDTH, 0, REG_MSSPLL_SSCG_2_CR),
148};
149
150static int mpfs_clk_register_mssplls(struct device *dev, struct mpfs_msspll_hw_clock *msspll_hws,
151				     unsigned int num_clks, struct mpfs_clock_data *data)
152{
153	unsigned int i;
154	int ret;
155
156	for (i = 0; i < num_clks; i++) {
157		struct mpfs_msspll_hw_clock *msspll_hw = &msspll_hws[i];
158
159		msspll_hw->base = data->msspll_base;
160		ret = devm_clk_hw_register(dev, &msspll_hw->hw);
161		if (ret)
162			return dev_err_probe(dev, ret, "failed to register msspll id: %d\n",
163					     CLK_MSSPLL_INTERNAL);
164
165		data->hw_data.hws[msspll_hw->id] = &msspll_hw->hw;
166	}
167
168	return 0;
169}
170
171/*
172 * MSS PLL output clocks
173 */
174
175#define CLK_PLL_OUT(_id, _name, _parent, _flags, _shift, _width, _offset) {	\
176	.id = _id,								\
177	.output.shift = _shift,							\
178	.output.width = _width,							\
179	.output.table = NULL,							\
180	.reg_offset = _offset,							\
181	.output.flags = _flags,							\
182	.output.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0),	\
183	.output.lock = &mpfs_clk_lock,						\
184}
185
186static struct mpfs_msspll_out_hw_clock mpfs_msspll_out_clks[] = {
187	CLK_PLL_OUT(CLK_MSSPLL0, "clk_msspll", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
188		    MSSPLL_POSTDIV02_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV01_CR),
189	CLK_PLL_OUT(CLK_MSSPLL1, "clk_msspll1", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
190		    MSSPLL_POSTDIV13_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV01_CR),
191	CLK_PLL_OUT(CLK_MSSPLL2, "clk_msspll2", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
192		    MSSPLL_POSTDIV02_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV23_CR),
193	CLK_PLL_OUT(CLK_MSSPLL3, "clk_msspll3", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
194		    MSSPLL_POSTDIV13_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV23_CR),
195};
196
197static int mpfs_clk_register_msspll_outs(struct device *dev,
198					 struct mpfs_msspll_out_hw_clock *msspll_out_hws,
199					 unsigned int num_clks, struct mpfs_clock_data *data)
200{
201	unsigned int i;
202	int ret;
203
204	for (i = 0; i < num_clks; i++) {
205		struct mpfs_msspll_out_hw_clock *msspll_out_hw = &msspll_out_hws[i];
206
207		msspll_out_hw->output.reg = data->msspll_base + msspll_out_hw->reg_offset;
208		ret = devm_clk_hw_register(dev, &msspll_out_hw->output.hw);
209		if (ret)
210			return dev_err_probe(dev, ret, "failed to register msspll out id: %d\n",
211					     msspll_out_hw->id);
212
213		data->hw_data.hws[msspll_out_hw->id] = &msspll_out_hw->output.hw;
214	}
215
216	return 0;
217}
218
219/*
220 * "CFG" clocks
221 */
222
223#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags, _offset) {		\
224	.id = _id,									\
225	.cfg.shift = _shift,								\
226	.cfg.width = _width,								\
227	.cfg.table = _table,								\
228	.reg_offset = _offset,								\
229	.cfg.flags = _flags,								\
230	.cfg.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0),		\
231	.cfg.lock = &mpfs_clk_lock,							\
232}
233
234#define CLK_CPU_OFFSET		0u
235#define CLK_AXI_OFFSET		1u
236#define CLK_AHB_OFFSET		2u
237#define CLK_RTCREF_OFFSET	3u
238
239static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
240	CLK_CFG(CLK_CPU, "clk_cpu", "clk_msspll", 0, 2, mpfs_div_cpu_axi_table, 0,
241		REG_CLOCK_CONFIG_CR),
242	CLK_CFG(CLK_AXI, "clk_axi", "clk_msspll", 2, 2, mpfs_div_cpu_axi_table, 0,
243		REG_CLOCK_CONFIG_CR),
244	CLK_CFG(CLK_AHB, "clk_ahb", "clk_msspll", 4, 2, mpfs_div_ahb_table, 0,
245		REG_CLOCK_CONFIG_CR),
246	{
247		.id = CLK_RTCREF,
248		.cfg.shift = 0,
249		.cfg.width = 12,
250		.cfg.table = mpfs_div_rtcref_table,
251		.reg_offset = REG_RTC_CLOCK_CR,
252		.cfg.flags = CLK_DIVIDER_ONE_BASED,
253		.cfg.hw.init =
254			CLK_HW_INIT_PARENTS_DATA("clk_rtcref", mpfs_ext_ref, &clk_divider_ops, 0),
255	}
256};
257
258static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
259				  unsigned int num_clks, struct mpfs_clock_data *data)
260{
261	unsigned int i, id;
262	int ret;
263
264	for (i = 0; i < num_clks; i++) {
265		struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
266
267		cfg_hw->cfg.reg = data->base + cfg_hw->reg_offset;
268		ret = devm_clk_hw_register(dev, &cfg_hw->cfg.hw);
269		if (ret)
270			return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
271					     cfg_hw->id);
272
273		id = cfg_hw->id;
274		data->hw_data.hws[id] = &cfg_hw->cfg.hw;
275	}
276
277	return 0;
278}
279
280/*
281 * peripheral clocks - devices connected to axi or ahb buses.
282 */
283
284#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) {			\
285	.id = _id,								\
286	.periph.bit_idx = _shift,						\
287	.periph.hw.init = CLK_HW_INIT_HW(_name, _parent, &clk_gate_ops,		\
288				  _flags),					\
289	.periph.lock = &mpfs_clk_lock,						\
290}
291
292#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT##_OFFSET].cfg.hw)
293
294/*
295 * Critical clocks:
296 * - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
297 *   trap handler
298 * - CLK_MMUART0: reserved by the hss
299 * - CLK_DDRC: provides clock to the ddr subsystem
300 * - CLK_RTC: the onboard RTC's AHB bus clock must be kept running as the rtc will stop
301 *   if the AHB interface clock is disabled
302 * - CLK_FICx: these provide the processor side clocks to the "FIC" (Fabric InterConnect)
303 *   clock domain crossers which provide the interface to the FPGA fabric. Disabling them
304 *   causes the FPGA fabric to go into reset.
305 * - CLK_ATHENA: The athena clock is FIC4, which is reserved for the Athena TeraFire.
306 */
307
308static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
309	CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
310	CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
311	CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
312	CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
313	CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(RTCREF), 4, 0),
314	CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
315	CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
316	CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
317	CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
318	CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
319	CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
320	CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
321	CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
322	CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
323	CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
324	CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
325	CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
326	CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, CLK_IS_CRITICAL),
327	CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
328	CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
329	CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
330	CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
331	CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
332	CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AXI), 24, CLK_IS_CRITICAL),
333	CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AXI), 25, CLK_IS_CRITICAL),
334	CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AXI), 26, CLK_IS_CRITICAL),
335	CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AXI), 27, CLK_IS_CRITICAL),
336	CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AXI), 28, CLK_IS_CRITICAL),
337	CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
338};
339
340static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
341				     int num_clks, struct mpfs_clock_data *data)
342{
343	unsigned int i, id;
344	int ret;
345
346	for (i = 0; i < num_clks; i++) {
347		struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];
348
349		periph_hw->periph.reg = data->base + REG_SUBBLK_CLOCK_CR;
350		ret = devm_clk_hw_register(dev, &periph_hw->periph.hw);
351		if (ret)
352			return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
353					     periph_hw->id);
354
355		id = periph_hws[i].id;
356		data->hw_data.hws[id] = &periph_hw->periph.hw;
357	}
358
359	return 0;
360}
361
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
362static int mpfs_clk_probe(struct platform_device *pdev)
363{
364	struct device *dev = &pdev->dev;
365	struct mpfs_clock_data *clk_data;
366	unsigned int num_clks;
367	int ret;
368
369	/* CLK_RESERVED is not part of clock arrays, so add 1 */
370	num_clks = ARRAY_SIZE(mpfs_msspll_clks) + ARRAY_SIZE(mpfs_msspll_out_clks)
371		   + ARRAY_SIZE(mpfs_cfg_clks)  + ARRAY_SIZE(mpfs_periph_clks) + 1;
372
373	clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
374	if (!clk_data)
375		return -ENOMEM;
376
377	clk_data->base = devm_platform_ioremap_resource(pdev, 0);
378	if (IS_ERR(clk_data->base))
379		return PTR_ERR(clk_data->base);
380
381	clk_data->msspll_base = devm_platform_ioremap_resource(pdev, 1);
382	if (IS_ERR(clk_data->msspll_base))
383		return PTR_ERR(clk_data->msspll_base);
384
385	clk_data->hw_data.num = num_clks;
386	clk_data->dev = dev;
387	dev_set_drvdata(dev, clk_data);
388
389	ret = mpfs_clk_register_mssplls(dev, mpfs_msspll_clks, ARRAY_SIZE(mpfs_msspll_clks),
390					clk_data);
391	if (ret)
392		return ret;
393
394	ret = mpfs_clk_register_msspll_outs(dev, mpfs_msspll_out_clks,
395					    ARRAY_SIZE(mpfs_msspll_out_clks),
396					    clk_data);
397	if (ret)
398		return ret;
399
400	ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
401	if (ret)
402		return ret;
403
404	ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
405					clk_data);
406	if (ret)
407		return ret;
408
409	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
410	if (ret)
411		return ret;
412
413	return mpfs_reset_controller_register(dev, clk_data->base + REG_SUBBLK_RESET_CR);
414}
415
416static const struct of_device_id mpfs_clk_of_match_table[] = {
417	{ .compatible = "microchip,mpfs-clkcfg", },
418	{}
419};
420MODULE_DEVICE_TABLE(of, mpfs_clk_of_match_table);
421
422static struct platform_driver mpfs_clk_driver = {
423	.probe = mpfs_clk_probe,
424	.driver	= {
425		.name = "microchip-mpfs-clkcfg",
426		.of_match_table = mpfs_clk_of_match_table,
427	},
428};
429
430static int __init clk_mpfs_init(void)
431{
432	return platform_driver_register(&mpfs_clk_driver);
433}
434core_initcall(clk_mpfs_init);
435
436static void __exit clk_mpfs_exit(void)
437{
438	platform_driver_unregister(&mpfs_clk_driver);
439}
440module_exit(clk_mpfs_exit);
441
442MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
443MODULE_AUTHOR("Padmarao Begari <padmarao.begari@microchip.com>");
444MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
445MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
446MODULE_IMPORT_NS("MCHP_CLK_MPFS");