xref: /linux/drivers/clk/clk-aspeed.c (revision 791d3ef2e11100449837dc0b6fe884e60ca3a484)
1 // SPDX-License-Identifier: GPL-2.0+
2 
3 #define pr_fmt(fmt) "clk-aspeed: " fmt
4 
5 #include <linux/clk-provider.h>
6 #include <linux/mfd/syscon.h>
7 #include <linux/of_address.h>
8 #include <linux/of_device.h>
9 #include <linux/platform_device.h>
10 #include <linux/regmap.h>
11 #include <linux/reset-controller.h>
12 #include <linux/slab.h>
13 #include <linux/spinlock.h>
14 
15 #include <dt-bindings/clock/aspeed-clock.h>
16 
17 #define ASPEED_NUM_CLKS		36
18 
19 #define ASPEED_RESET2_OFFSET	32
20 
21 #define ASPEED_RESET_CTRL	0x04
22 #define ASPEED_CLK_SELECTION	0x08
23 #define ASPEED_CLK_STOP_CTRL	0x0c
24 #define ASPEED_MPLL_PARAM	0x20
25 #define ASPEED_HPLL_PARAM	0x24
26 #define  AST2500_HPLL_BYPASS_EN	BIT(20)
27 #define  AST2400_HPLL_STRAPPED	BIT(18)
28 #define  AST2400_HPLL_BYPASS_EN	BIT(17)
29 #define ASPEED_MISC_CTRL	0x2c
30 #define  UART_DIV13_EN		BIT(12)
31 #define ASPEED_STRAP		0x70
32 #define  CLKIN_25MHZ_EN		BIT(23)
33 #define  AST2400_CLK_SOURCE_SEL	BIT(18)
34 #define ASPEED_CLK_SELECTION_2	0xd8
35 #define ASPEED_RESET_CTRL2	0xd4
36 
37 /* Globally visible clocks */
38 static DEFINE_SPINLOCK(aspeed_clk_lock);
39 
40 /* Keeps track of all clocks */
41 static struct clk_hw_onecell_data *aspeed_clk_data;
42 
43 static void __iomem *scu_base;
44 
45 /**
46  * struct aspeed_gate_data - Aspeed gated clocks
47  * @clock_idx: bit used to gate this clock in the clock register
48  * @reset_idx: bit used to reset this IP in the reset register. -1 if no
49  *             reset is required when enabling the clock
50  * @name: the clock name
51  * @parent_name: the name of the parent clock
52  * @flags: standard clock framework flags
53  */
54 struct aspeed_gate_data {
55 	u8		clock_idx;
56 	s8		reset_idx;
57 	const char	*name;
58 	const char	*parent_name;
59 	unsigned long	flags;
60 };
61 
62 /**
63  * struct aspeed_clk_gate - Aspeed specific clk_gate structure
64  * @hw:		handle between common and hardware-specific interfaces
65  * @reg:	register controlling gate
66  * @clock_idx:	bit used to gate this clock in the clock register
67  * @reset_idx:	bit used to reset this IP in the reset register. -1 if no
68  *		reset is required when enabling the clock
69  * @flags:	hardware-specific flags
70  * @lock:	register lock
71  *
72  * Some of the clocks in the Aspeed SoC must be put in reset before enabling.
73  * This modified version of clk_gate allows an optional reset bit to be
74  * specified.
75  */
76 struct aspeed_clk_gate {
77 	struct clk_hw	hw;
78 	struct regmap	*map;
79 	u8		clock_idx;
80 	s8		reset_idx;
81 	u8		flags;
82 	spinlock_t	*lock;
83 };
84 
85 #define to_aspeed_clk_gate(_hw) container_of(_hw, struct aspeed_clk_gate, hw)
86 
87 /* TODO: ask Aspeed about the actual parent data */
88 static const struct aspeed_gate_data aspeed_gates[] = {
89 	/*				 clk rst   name			parent	flags */
90 	[ASPEED_CLK_GATE_ECLK] =	{  0, -1, "eclk-gate",		"eclk",	0 }, /* Video Engine */
91 	[ASPEED_CLK_GATE_GCLK] =	{  1,  7, "gclk-gate",		NULL,	0 }, /* 2D engine */
92 	[ASPEED_CLK_GATE_MCLK] =	{  2, -1, "mclk-gate",		"mpll",	CLK_IS_CRITICAL }, /* SDRAM */
93 	[ASPEED_CLK_GATE_VCLK] =	{  3,  6, "vclk-gate",		NULL,	0 }, /* Video Capture */
94 	[ASPEED_CLK_GATE_BCLK] =	{  4,  8, "bclk-gate",		"bclk",	0 }, /* PCIe/PCI */
95 	[ASPEED_CLK_GATE_DCLK] =	{  5, -1, "dclk-gate",		NULL,	0 }, /* DAC */
96 	[ASPEED_CLK_GATE_REFCLK] =	{  6, -1, "refclk-gate",	"clkin", CLK_IS_CRITICAL },
97 	[ASPEED_CLK_GATE_USBPORT2CLK] =	{  7,  3, "usb-port2-gate",	NULL,	0 }, /* USB2.0 Host port 2 */
98 	[ASPEED_CLK_GATE_LCLK] =	{  8,  5, "lclk-gate",		NULL,	0 }, /* LPC */
99 	[ASPEED_CLK_GATE_USBUHCICLK] =	{  9, 15, "usb-uhci-gate",	NULL,	0 }, /* USB1.1 (requires port 2 enabled) */
100 	[ASPEED_CLK_GATE_D1CLK] =	{ 10, 13, "d1clk-gate",		NULL,	0 }, /* GFX CRT */
101 	[ASPEED_CLK_GATE_YCLK] =	{ 13,  4, "yclk-gate",		NULL,	0 }, /* HAC */
102 	[ASPEED_CLK_GATE_USBPORT1CLK] = { 14, 14, "usb-port1-gate",	NULL,	0 }, /* USB2 hub/USB2 host port 1/USB1.1 dev */
103 	[ASPEED_CLK_GATE_UART1CLK] =	{ 15, -1, "uart1clk-gate",	"uart",	0 }, /* UART1 */
104 	[ASPEED_CLK_GATE_UART2CLK] =	{ 16, -1, "uart2clk-gate",	"uart",	0 }, /* UART2 */
105 	[ASPEED_CLK_GATE_UART5CLK] =	{ 17, -1, "uart5clk-gate",	"uart",	0 }, /* UART5 */
106 	[ASPEED_CLK_GATE_ESPICLK] =	{ 19, -1, "espiclk-gate",	NULL,	0 }, /* eSPI */
107 	[ASPEED_CLK_GATE_MAC1CLK] =	{ 20, 11, "mac1clk-gate",	"mac",	0 }, /* MAC1 */
108 	[ASPEED_CLK_GATE_MAC2CLK] =	{ 21, 12, "mac2clk-gate",	"mac",	0 }, /* MAC2 */
109 	[ASPEED_CLK_GATE_RSACLK] =	{ 24, -1, "rsaclk-gate",	NULL,	0 }, /* RSA */
110 	[ASPEED_CLK_GATE_UART3CLK] =	{ 25, -1, "uart3clk-gate",	"uart",	0 }, /* UART3 */
111 	[ASPEED_CLK_GATE_UART4CLK] =	{ 26, -1, "uart4clk-gate",	"uart",	0 }, /* UART4 */
112 	[ASPEED_CLK_GATE_SDCLKCLK] =	{ 27, 16, "sdclk-gate",		NULL,	0 }, /* SDIO/SD */
113 	[ASPEED_CLK_GATE_LHCCLK] =	{ 28, -1, "lhclk-gate",		"lhclk", 0 }, /* LPC master/LPC+ */
114 };
115 
116 static const struct clk_div_table ast2500_mac_div_table[] = {
117 	{ 0x0, 4 }, /* Yep, really. Aspeed confirmed this is correct */
118 	{ 0x1, 4 },
119 	{ 0x2, 6 },
120 	{ 0x3, 8 },
121 	{ 0x4, 10 },
122 	{ 0x5, 12 },
123 	{ 0x6, 14 },
124 	{ 0x7, 16 },
125 	{ 0 }
126 };
127 
128 static const struct clk_div_table ast2400_div_table[] = {
129 	{ 0x0, 2 },
130 	{ 0x1, 4 },
131 	{ 0x2, 6 },
132 	{ 0x3, 8 },
133 	{ 0x4, 10 },
134 	{ 0x5, 12 },
135 	{ 0x6, 14 },
136 	{ 0x7, 16 },
137 	{ 0 }
138 };
139 
140 static const struct clk_div_table ast2500_div_table[] = {
141 	{ 0x0, 4 },
142 	{ 0x1, 8 },
143 	{ 0x2, 12 },
144 	{ 0x3, 16 },
145 	{ 0x4, 20 },
146 	{ 0x5, 24 },
147 	{ 0x6, 28 },
148 	{ 0x7, 32 },
149 	{ 0 }
150 };
151 
152 static struct clk_hw *aspeed_ast2400_calc_pll(const char *name, u32 val)
153 {
154 	unsigned int mult, div;
155 
156 	if (val & AST2400_HPLL_BYPASS_EN) {
157 		/* Pass through mode */
158 		mult = div = 1;
159 	} else {
160 		/* F = 24Mhz * (2-OD) * [(N + 2) / (D + 1)] */
161 		u32 n = (val >> 5) & 0x3f;
162 		u32 od = (val >> 4) & 0x1;
163 		u32 d = val & 0xf;
164 
165 		mult = (2 - od) * (n + 2);
166 		div = d + 1;
167 	}
168 	return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
169 			mult, div);
170 };
171 
172 static struct clk_hw *aspeed_ast2500_calc_pll(const char *name, u32 val)
173 {
174 	unsigned int mult, div;
175 
176 	if (val & AST2500_HPLL_BYPASS_EN) {
177 		/* Pass through mode */
178 		mult = div = 1;
179 	} else {
180 		/* F = clkin * [(M+1) / (N+1)] / (P + 1) */
181 		u32 p = (val >> 13) & 0x3f;
182 		u32 m = (val >> 5) & 0xff;
183 		u32 n = val & 0x1f;
184 
185 		mult = (m + 1) / (n + 1);
186 		div = p + 1;
187 	}
188 
189 	return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
190 			mult, div);
191 }
192 
193 struct aspeed_clk_soc_data {
194 	const struct clk_div_table *div_table;
195 	const struct clk_div_table *mac_div_table;
196 	struct clk_hw *(*calc_pll)(const char *name, u32 val);
197 };
198 
199 static const struct aspeed_clk_soc_data ast2500_data = {
200 	.div_table = ast2500_div_table,
201 	.mac_div_table = ast2500_mac_div_table,
202 	.calc_pll = aspeed_ast2500_calc_pll,
203 };
204 
205 static const struct aspeed_clk_soc_data ast2400_data = {
206 	.div_table = ast2400_div_table,
207 	.mac_div_table = ast2400_div_table,
208 	.calc_pll = aspeed_ast2400_calc_pll,
209 };
210 
211 static int aspeed_clk_is_enabled(struct clk_hw *hw)
212 {
213 	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
214 	u32 clk = BIT(gate->clock_idx);
215 	u32 enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
216 	u32 reg;
217 
218 	regmap_read(gate->map, ASPEED_CLK_STOP_CTRL, &reg);
219 
220 	return ((reg & clk) == enval) ? 1 : 0;
221 }
222 
223 static int aspeed_clk_enable(struct clk_hw *hw)
224 {
225 	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
226 	unsigned long flags;
227 	u32 clk = BIT(gate->clock_idx);
228 	u32 rst = BIT(gate->reset_idx);
229 	u32 enval;
230 
231 	spin_lock_irqsave(gate->lock, flags);
232 
233 	if (aspeed_clk_is_enabled(hw)) {
234 		spin_unlock_irqrestore(gate->lock, flags);
235 		return 0;
236 	}
237 
238 	if (gate->reset_idx >= 0) {
239 		/* Put IP in reset */
240 		regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, rst);
241 
242 		/* Delay 100us */
243 		udelay(100);
244 	}
245 
246 	/* Enable clock */
247 	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
248 	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
249 
250 	if (gate->reset_idx >= 0) {
251 		/* A delay of 10ms is specified by the ASPEED docs */
252 		mdelay(10);
253 
254 		/* Take IP out of reset */
255 		regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, 0);
256 	}
257 
258 	spin_unlock_irqrestore(gate->lock, flags);
259 
260 	return 0;
261 }
262 
263 static void aspeed_clk_disable(struct clk_hw *hw)
264 {
265 	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
266 	unsigned long flags;
267 	u32 clk = BIT(gate->clock_idx);
268 	u32 enval;
269 
270 	spin_lock_irqsave(gate->lock, flags);
271 
272 	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? clk : 0;
273 	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
274 
275 	spin_unlock_irqrestore(gate->lock, flags);
276 }
277 
278 static const struct clk_ops aspeed_clk_gate_ops = {
279 	.enable = aspeed_clk_enable,
280 	.disable = aspeed_clk_disable,
281 	.is_enabled = aspeed_clk_is_enabled,
282 };
283 
284 /**
285  * struct aspeed_reset - Aspeed reset controller
286  * @map: regmap to access the containing system controller
287  * @rcdev: reset controller device
288  */
289 struct aspeed_reset {
290 	struct regmap			*map;
291 	struct reset_controller_dev	rcdev;
292 };
293 
294 #define to_aspeed_reset(p) container_of((p), struct aspeed_reset, rcdev)
295 
296 static const u8 aspeed_resets[] = {
297 	/* SCU04 resets */
298 	[ASPEED_RESET_XDMA]	= 25,
299 	[ASPEED_RESET_MCTP]	= 24,
300 	[ASPEED_RESET_ADC]	= 23,
301 	[ASPEED_RESET_JTAG_MASTER] = 22,
302 	[ASPEED_RESET_MIC]	= 18,
303 	[ASPEED_RESET_PWM]	=  9,
304 	[ASPEED_RESET_PECI]	= 10,
305 	[ASPEED_RESET_I2C]	=  2,
306 	[ASPEED_RESET_AHB]	=  1,
307 
308 	/*
309 	 * SCUD4 resets start at an offset to separate them from
310 	 * the SCU04 resets.
311 	 */
312 	[ASPEED_RESET_CRT1]	= ASPEED_RESET2_OFFSET + 5,
313 };
314 
315 static int aspeed_reset_deassert(struct reset_controller_dev *rcdev,
316 				 unsigned long id)
317 {
318 	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
319 	u32 reg = ASPEED_RESET_CTRL;
320 	u32 bit = aspeed_resets[id];
321 
322 	if (bit >= ASPEED_RESET2_OFFSET) {
323 		bit -= ASPEED_RESET2_OFFSET;
324 		reg = ASPEED_RESET_CTRL2;
325 	}
326 
327 	return regmap_update_bits(ar->map, reg, BIT(bit), 0);
328 }
329 
330 static int aspeed_reset_assert(struct reset_controller_dev *rcdev,
331 			       unsigned long id)
332 {
333 	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
334 	u32 reg = ASPEED_RESET_CTRL;
335 	u32 bit = aspeed_resets[id];
336 
337 	if (bit >= ASPEED_RESET2_OFFSET) {
338 		bit -= ASPEED_RESET2_OFFSET;
339 		reg = ASPEED_RESET_CTRL2;
340 	}
341 
342 	return regmap_update_bits(ar->map, reg, BIT(bit), BIT(bit));
343 }
344 
345 static int aspeed_reset_status(struct reset_controller_dev *rcdev,
346 			       unsigned long id)
347 {
348 	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
349 	u32 reg = ASPEED_RESET_CTRL;
350 	u32 bit = aspeed_resets[id];
351 	int ret, val;
352 
353 	if (bit >= ASPEED_RESET2_OFFSET) {
354 		bit -= ASPEED_RESET2_OFFSET;
355 		reg = ASPEED_RESET_CTRL2;
356 	}
357 
358 	ret = regmap_read(ar->map, reg, &val);
359 	if (ret)
360 		return ret;
361 
362 	return !!(val & BIT(bit));
363 }
364 
365 static const struct reset_control_ops aspeed_reset_ops = {
366 	.assert = aspeed_reset_assert,
367 	.deassert = aspeed_reset_deassert,
368 	.status = aspeed_reset_status,
369 };
370 
371 static struct clk_hw *aspeed_clk_hw_register_gate(struct device *dev,
372 		const char *name, const char *parent_name, unsigned long flags,
373 		struct regmap *map, u8 clock_idx, u8 reset_idx,
374 		u8 clk_gate_flags, spinlock_t *lock)
375 {
376 	struct aspeed_clk_gate *gate;
377 	struct clk_init_data init;
378 	struct clk_hw *hw;
379 	int ret;
380 
381 	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
382 	if (!gate)
383 		return ERR_PTR(-ENOMEM);
384 
385 	init.name = name;
386 	init.ops = &aspeed_clk_gate_ops;
387 	init.flags = flags;
388 	init.parent_names = parent_name ? &parent_name : NULL;
389 	init.num_parents = parent_name ? 1 : 0;
390 
391 	gate->map = map;
392 	gate->clock_idx = clock_idx;
393 	gate->reset_idx = reset_idx;
394 	gate->flags = clk_gate_flags;
395 	gate->lock = lock;
396 	gate->hw.init = &init;
397 
398 	hw = &gate->hw;
399 	ret = clk_hw_register(dev, hw);
400 	if (ret) {
401 		kfree(gate);
402 		hw = ERR_PTR(ret);
403 	}
404 
405 	return hw;
406 }
407 
408 static int aspeed_clk_probe(struct platform_device *pdev)
409 {
410 	const struct aspeed_clk_soc_data *soc_data;
411 	struct device *dev = &pdev->dev;
412 	struct aspeed_reset *ar;
413 	struct regmap *map;
414 	struct clk_hw *hw;
415 	u32 val, rate;
416 	int i, ret;
417 
418 	map = syscon_node_to_regmap(dev->of_node);
419 	if (IS_ERR(map)) {
420 		dev_err(dev, "no syscon regmap\n");
421 		return PTR_ERR(map);
422 	}
423 
424 	ar = devm_kzalloc(dev, sizeof(*ar), GFP_KERNEL);
425 	if (!ar)
426 		return -ENOMEM;
427 
428 	ar->map = map;
429 	ar->rcdev.owner = THIS_MODULE;
430 	ar->rcdev.nr_resets = ARRAY_SIZE(aspeed_resets);
431 	ar->rcdev.ops = &aspeed_reset_ops;
432 	ar->rcdev.of_node = dev->of_node;
433 
434 	ret = devm_reset_controller_register(dev, &ar->rcdev);
435 	if (ret) {
436 		dev_err(dev, "could not register reset controller\n");
437 		return ret;
438 	}
439 
440 	/* SoC generations share common layouts but have different divisors */
441 	soc_data = of_device_get_match_data(dev);
442 	if (!soc_data) {
443 		dev_err(dev, "no match data for platform\n");
444 		return -EINVAL;
445 	}
446 
447 	/* UART clock div13 setting */
448 	regmap_read(map, ASPEED_MISC_CTRL, &val);
449 	if (val & UART_DIV13_EN)
450 		rate = 24000000 / 13;
451 	else
452 		rate = 24000000;
453 	/* TODO: Find the parent data for the uart clock */
454 	hw = clk_hw_register_fixed_rate(dev, "uart", NULL, 0, rate);
455 	if (IS_ERR(hw))
456 		return PTR_ERR(hw);
457 	aspeed_clk_data->hws[ASPEED_CLK_UART] = hw;
458 
459 	/*
460 	 * Memory controller (M-PLL) PLL. This clock is configured by the
461 	 * bootloader, and is exposed to Linux as a read-only clock rate.
462 	 */
463 	regmap_read(map, ASPEED_MPLL_PARAM, &val);
464 	hw = soc_data->calc_pll("mpll", val);
465 	if (IS_ERR(hw))
466 		return PTR_ERR(hw);
467 	aspeed_clk_data->hws[ASPEED_CLK_MPLL] =	hw;
468 
469 	/* SD/SDIO clock divider (TODO: There's a gate too) */
470 	hw = clk_hw_register_divider_table(dev, "sdio", "hpll", 0,
471 			scu_base + ASPEED_CLK_SELECTION, 12, 3, 0,
472 			soc_data->div_table,
473 			&aspeed_clk_lock);
474 	if (IS_ERR(hw))
475 		return PTR_ERR(hw);
476 	aspeed_clk_data->hws[ASPEED_CLK_SDIO] = hw;
477 
478 	/* MAC AHB bus clock divider */
479 	hw = clk_hw_register_divider_table(dev, "mac", "hpll", 0,
480 			scu_base + ASPEED_CLK_SELECTION, 16, 3, 0,
481 			soc_data->mac_div_table,
482 			&aspeed_clk_lock);
483 	if (IS_ERR(hw))
484 		return PTR_ERR(hw);
485 	aspeed_clk_data->hws[ASPEED_CLK_MAC] = hw;
486 
487 	/* LPC Host (LHCLK) clock divider */
488 	hw = clk_hw_register_divider_table(dev, "lhclk", "hpll", 0,
489 			scu_base + ASPEED_CLK_SELECTION, 20, 3, 0,
490 			soc_data->div_table,
491 			&aspeed_clk_lock);
492 	if (IS_ERR(hw))
493 		return PTR_ERR(hw);
494 	aspeed_clk_data->hws[ASPEED_CLK_LHCLK] = hw;
495 
496 	/* P-Bus (BCLK) clock divider */
497 	hw = clk_hw_register_divider_table(dev, "bclk", "hpll", 0,
498 			scu_base + ASPEED_CLK_SELECTION_2, 0, 2, 0,
499 			soc_data->div_table,
500 			&aspeed_clk_lock);
501 	if (IS_ERR(hw))
502 		return PTR_ERR(hw);
503 	aspeed_clk_data->hws[ASPEED_CLK_BCLK] = hw;
504 
505 	/* Fixed 24MHz clock */
506 	hw = clk_hw_register_fixed_rate(NULL, "fixed-24m", "clkin",
507 					0, 24000000);
508 	if (IS_ERR(hw))
509 		return PTR_ERR(hw);
510 	aspeed_clk_data->hws[ASPEED_CLK_24M] = hw;
511 
512 	/*
513 	 * TODO: There are a number of clocks that not included in this driver
514 	 * as more information is required:
515 	 *   D2-PLL
516 	 *   D-PLL
517 	 *   YCLK
518 	 *   RGMII
519 	 *   RMII
520 	 *   UART[1..5] clock source mux
521 	 *   Video Engine (ECLK) mux and clock divider
522 	 */
523 
524 	for (i = 0; i < ARRAY_SIZE(aspeed_gates); i++) {
525 		const struct aspeed_gate_data *gd = &aspeed_gates[i];
526 		u32 gate_flags;
527 
528 		/* Special case: the USB port 1 clock (bit 14) is always
529 		 * working the opposite way from the other ones.
530 		 */
531 		gate_flags = (gd->clock_idx == 14) ? 0 : CLK_GATE_SET_TO_DISABLE;
532 		hw = aspeed_clk_hw_register_gate(dev,
533 				gd->name,
534 				gd->parent_name,
535 				gd->flags,
536 				map,
537 				gd->clock_idx,
538 				gd->reset_idx,
539 				gate_flags,
540 				&aspeed_clk_lock);
541 		if (IS_ERR(hw))
542 			return PTR_ERR(hw);
543 		aspeed_clk_data->hws[i] = hw;
544 	}
545 
546 	return 0;
547 };
548 
549 static const struct of_device_id aspeed_clk_dt_ids[] = {
550 	{ .compatible = "aspeed,ast2400-scu", .data = &ast2400_data },
551 	{ .compatible = "aspeed,ast2500-scu", .data = &ast2500_data },
552 	{ }
553 };
554 
555 static struct platform_driver aspeed_clk_driver = {
556 	.probe  = aspeed_clk_probe,
557 	.driver = {
558 		.name = "aspeed-clk",
559 		.of_match_table = aspeed_clk_dt_ids,
560 		.suppress_bind_attrs = true,
561 	},
562 };
563 builtin_platform_driver(aspeed_clk_driver);
564 
565 static void __init aspeed_ast2400_cc(struct regmap *map)
566 {
567 	struct clk_hw *hw;
568 	u32 val, freq, div;
569 
570 	/*
571 	 * CLKIN is the crystal oscillator, 24, 48 or 25MHz selected by
572 	 * strapping
573 	 */
574 	regmap_read(map, ASPEED_STRAP, &val);
575 	if (val & CLKIN_25MHZ_EN)
576 		freq = 25000000;
577 	else if (val & AST2400_CLK_SOURCE_SEL)
578 		freq = 48000000;
579 	else
580 		freq = 24000000;
581 	hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, freq);
582 	pr_debug("clkin @%u MHz\n", freq / 1000000);
583 
584 	/*
585 	 * High-speed PLL clock derived from the crystal. This the CPU clock,
586 	 * and we assume that it is enabled
587 	 */
588 	regmap_read(map, ASPEED_HPLL_PARAM, &val);
589 	WARN(val & AST2400_HPLL_STRAPPED, "hpll is strapped not configured");
590 	aspeed_clk_data->hws[ASPEED_CLK_HPLL] = aspeed_ast2400_calc_pll("hpll", val);
591 
592 	/*
593 	 * Strap bits 11:10 define the CPU/AHB clock frequency ratio (aka HCLK)
594 	 *   00: Select CPU:AHB = 1:1
595 	 *   01: Select CPU:AHB = 2:1
596 	 *   10: Select CPU:AHB = 4:1
597 	 *   11: Select CPU:AHB = 3:1
598 	 */
599 	regmap_read(map, ASPEED_STRAP, &val);
600 	val = (val >> 10) & 0x3;
601 	div = val + 1;
602 	if (div == 3)
603 		div = 4;
604 	else if (div == 4)
605 		div = 3;
606 	hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
607 	aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
608 
609 	/* APB clock clock selection register SCU08 (aka PCLK) */
610 	hw = clk_hw_register_divider_table(NULL, "apb", "hpll", 0,
611 			scu_base + ASPEED_CLK_SELECTION, 23, 3, 0,
612 			ast2400_div_table,
613 			&aspeed_clk_lock);
614 	aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
615 }
616 
617 static void __init aspeed_ast2500_cc(struct regmap *map)
618 {
619 	struct clk_hw *hw;
620 	u32 val, freq, div;
621 
622 	/* CLKIN is the crystal oscillator, 24 or 25MHz selected by strapping */
623 	regmap_read(map, ASPEED_STRAP, &val);
624 	if (val & CLKIN_25MHZ_EN)
625 		freq = 25000000;
626 	else
627 		freq = 24000000;
628 	hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, freq);
629 	pr_debug("clkin @%u MHz\n", freq / 1000000);
630 
631 	/*
632 	 * High-speed PLL clock derived from the crystal. This the CPU clock,
633 	 * and we assume that it is enabled
634 	 */
635 	regmap_read(map, ASPEED_HPLL_PARAM, &val);
636 	aspeed_clk_data->hws[ASPEED_CLK_HPLL] = aspeed_ast2500_calc_pll("hpll", val);
637 
638 	/* Strap bits 11:9 define the AXI/AHB clock frequency ratio (aka HCLK)*/
639 	regmap_read(map, ASPEED_STRAP, &val);
640 	val = (val >> 9) & 0x7;
641 	WARN(val == 0, "strapping is zero: cannot determine ahb clock");
642 	div = 2 * (val + 1);
643 	hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
644 	aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
645 
646 	/* APB clock clock selection register SCU08 (aka PCLK) */
647 	regmap_read(map, ASPEED_CLK_SELECTION, &val);
648 	val = (val >> 23) & 0x7;
649 	div = 4 * (val + 1);
650 	hw = clk_hw_register_fixed_factor(NULL, "apb", "hpll", 0, 1, div);
651 	aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
652 };
653 
654 static void __init aspeed_cc_init(struct device_node *np)
655 {
656 	struct regmap *map;
657 	u32 val;
658 	int ret;
659 	int i;
660 
661 	scu_base = of_iomap(np, 0);
662 	if (!scu_base)
663 		return;
664 
665 	aspeed_clk_data = kzalloc(struct_size(aspeed_clk_data, hws,
666 					      ASPEED_NUM_CLKS),
667 				  GFP_KERNEL);
668 	if (!aspeed_clk_data)
669 		return;
670 
671 	/*
672 	 * This way all clocks fetched before the platform device probes,
673 	 * except those we assign here for early use, will be deferred.
674 	 */
675 	for (i = 0; i < ASPEED_NUM_CLKS; i++)
676 		aspeed_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);
677 
678 	map = syscon_node_to_regmap(np);
679 	if (IS_ERR(map)) {
680 		pr_err("no syscon regmap\n");
681 		return;
682 	}
683 	/*
684 	 * We check that the regmap works on this very first access,
685 	 * but as this is an MMIO-backed regmap, subsequent regmap
686 	 * access is not going to fail and we skip error checks from
687 	 * this point.
688 	 */
689 	ret = regmap_read(map, ASPEED_STRAP, &val);
690 	if (ret) {
691 		pr_err("failed to read strapping register\n");
692 		return;
693 	}
694 
695 	if (of_device_is_compatible(np, "aspeed,ast2400-scu"))
696 		aspeed_ast2400_cc(map);
697 	else if (of_device_is_compatible(np, "aspeed,ast2500-scu"))
698 		aspeed_ast2500_cc(map);
699 	else
700 		pr_err("unknown platform, failed to add clocks\n");
701 
702 	aspeed_clk_data->num = ASPEED_NUM_CLKS;
703 	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, aspeed_clk_data);
704 	if (ret)
705 		pr_err("failed to add DT provider: %d\n", ret);
706 };
707 CLK_OF_DECLARE_DRIVER(aspeed_cc_g5, "aspeed,ast2500-scu", aspeed_cc_init);
708 CLK_OF_DECLARE_DRIVER(aspeed_cc_g4, "aspeed,ast2400-scu", aspeed_cc_init);
709