xref: /openbmc/linux/drivers/clk/clk-aspeed.c (revision d9e32672)
1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright IBM Corp
3 
4 #define pr_fmt(fmt) "clk-aspeed: " fmt
5 
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/slab.h>
12 
13 #include <dt-bindings/clock/aspeed-clock.h>
14 
15 #include "clk-aspeed.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_PROGRAMMED 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 /* TODO: ask Aspeed about the actual parent data */
46 static const struct aspeed_gate_data aspeed_gates[] = {
47 	/*				 clk rst   name			parent	flags */
48 	[ASPEED_CLK_GATE_ECLK] =	{  0,  6, "eclk-gate",		"eclk",	0 }, /* Video Engine */
49 	[ASPEED_CLK_GATE_GCLK] =	{  1,  7, "gclk-gate",		NULL,	0 }, /* 2D engine */
50 	[ASPEED_CLK_GATE_MCLK] =	{  2, -1, "mclk-gate",		"mpll",	CLK_IS_CRITICAL }, /* SDRAM */
51 	[ASPEED_CLK_GATE_VCLK] =	{  3, -1, "vclk-gate",		NULL,	0 }, /* Video Capture */
52 	[ASPEED_CLK_GATE_BCLK] =	{  4,  8, "bclk-gate",		"bclk",	CLK_IS_CRITICAL }, /* PCIe/PCI */
53 	[ASPEED_CLK_GATE_DCLK] =	{  5, -1, "dclk-gate",		NULL,	CLK_IS_CRITICAL }, /* DAC */
54 	[ASPEED_CLK_GATE_REFCLK] =	{  6, -1, "refclk-gate",	"clkin", CLK_IS_CRITICAL },
55 	[ASPEED_CLK_GATE_USBPORT2CLK] =	{  7,  3, "usb-port2-gate",	NULL,	0 }, /* USB2.0 Host port 2 */
56 	[ASPEED_CLK_GATE_LCLK] =	{  8,  5, "lclk-gate",		NULL,	0 }, /* LPC */
57 	[ASPEED_CLK_GATE_USBUHCICLK] =	{  9, 15, "usb-uhci-gate",	NULL,	0 }, /* USB1.1 (requires port 2 enabled) */
58 	[ASPEED_CLK_GATE_D1CLK] =	{ 10, 13, "d1clk-gate",		NULL,	0 }, /* GFX CRT */
59 	[ASPEED_CLK_GATE_YCLK] =	{ 13,  4, "yclk-gate",		NULL,	0 }, /* HAC */
60 	[ASPEED_CLK_GATE_USBPORT1CLK] = { 14, 14, "usb-port1-gate",	NULL,	0 }, /* USB2 hub/USB2 host port 1/USB1.1 dev */
61 	[ASPEED_CLK_GATE_UART1CLK] =	{ 15, -1, "uart1clk-gate",	"uart",	0 }, /* UART1 */
62 	[ASPEED_CLK_GATE_UART2CLK] =	{ 16, -1, "uart2clk-gate",	"uart",	0 }, /* UART2 */
63 	[ASPEED_CLK_GATE_UART5CLK] =	{ 17, -1, "uart5clk-gate",	"uart",	0 }, /* UART5 */
64 	[ASPEED_CLK_GATE_ESPICLK] =	{ 19, -1, "espiclk-gate",	NULL,	0 }, /* eSPI */
65 	[ASPEED_CLK_GATE_MAC1CLK] =	{ 20, 11, "mac1clk-gate",	"mac",	0 }, /* MAC1 */
66 	[ASPEED_CLK_GATE_MAC2CLK] =	{ 21, 12, "mac2clk-gate",	"mac",	0 }, /* MAC2 */
67 	[ASPEED_CLK_GATE_RSACLK] =	{ 24, -1, "rsaclk-gate",	NULL,	0 }, /* RSA */
68 	[ASPEED_CLK_GATE_UART3CLK] =	{ 25, -1, "uart3clk-gate",	"uart",	0 }, /* UART3 */
69 	[ASPEED_CLK_GATE_UART4CLK] =	{ 26, -1, "uart4clk-gate",	"uart",	0 }, /* UART4 */
70 	[ASPEED_CLK_GATE_SDCLK] =	{ 27, 16, "sdclk-gate",		NULL,	0 }, /* SDIO/SD */
71 	[ASPEED_CLK_GATE_LHCCLK] =	{ 28, -1, "lhclk-gate",		"lhclk", 0 }, /* LPC master/LPC+ */
72 };
73 
74 static const char * const eclk_parent_names[] = {
75 	"mpll",
76 	"hpll",
77 	"dpll",
78 };
79 
80 static const struct clk_div_table ast2500_eclk_div_table[] = {
81 	{ 0x0, 2 },
82 	{ 0x1, 2 },
83 	{ 0x2, 3 },
84 	{ 0x3, 4 },
85 	{ 0x4, 5 },
86 	{ 0x5, 6 },
87 	{ 0x6, 7 },
88 	{ 0x7, 8 },
89 	{ 0 }
90 };
91 
92 static const struct clk_div_table ast2500_mac_div_table[] = {
93 	{ 0x0, 4 }, /* Yep, really. Aspeed confirmed this is correct */
94 	{ 0x1, 4 },
95 	{ 0x2, 6 },
96 	{ 0x3, 8 },
97 	{ 0x4, 10 },
98 	{ 0x5, 12 },
99 	{ 0x6, 14 },
100 	{ 0x7, 16 },
101 	{ 0 }
102 };
103 
104 static const struct clk_div_table ast2400_div_table[] = {
105 	{ 0x0, 2 },
106 	{ 0x1, 4 },
107 	{ 0x2, 6 },
108 	{ 0x3, 8 },
109 	{ 0x4, 10 },
110 	{ 0x5, 12 },
111 	{ 0x6, 14 },
112 	{ 0x7, 16 },
113 	{ 0 }
114 };
115 
116 static const struct clk_div_table ast2500_div_table[] = {
117 	{ 0x0, 4 },
118 	{ 0x1, 8 },
119 	{ 0x2, 12 },
120 	{ 0x3, 16 },
121 	{ 0x4, 20 },
122 	{ 0x5, 24 },
123 	{ 0x6, 28 },
124 	{ 0x7, 32 },
125 	{ 0 }
126 };
127 
128 static struct clk_hw *aspeed_ast2400_calc_pll(const char *name, u32 val)
129 {
130 	unsigned int mult, div;
131 
132 	if (val & AST2400_HPLL_BYPASS_EN) {
133 		/* Pass through mode */
134 		mult = div = 1;
135 	} else {
136 		/* F = 24Mhz * (2-OD) * [(N + 2) / (D + 1)] */
137 		u32 n = (val >> 5) & 0x3f;
138 		u32 od = (val >> 4) & 0x1;
139 		u32 d = val & 0xf;
140 
141 		mult = (2 - od) * (n + 2);
142 		div = d + 1;
143 	}
144 	return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
145 			mult, div);
146 };
147 
148 static struct clk_hw *aspeed_ast2500_calc_pll(const char *name, u32 val)
149 {
150 	unsigned int mult, div;
151 
152 	if (val & AST2500_HPLL_BYPASS_EN) {
153 		/* Pass through mode */
154 		mult = div = 1;
155 	} else {
156 		/* F = clkin * [(M+1) / (N+1)] / (P + 1) */
157 		u32 p = (val >> 13) & 0x3f;
158 		u32 m = (val >> 5) & 0xff;
159 		u32 n = val & 0x1f;
160 
161 		mult = (m + 1) / (n + 1);
162 		div = p + 1;
163 	}
164 
165 	return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
166 			mult, div);
167 }
168 
169 static const struct aspeed_clk_soc_data ast2500_data = {
170 	.div_table = ast2500_div_table,
171 	.eclk_div_table = ast2500_eclk_div_table,
172 	.mac_div_table = ast2500_mac_div_table,
173 	.calc_pll = aspeed_ast2500_calc_pll,
174 };
175 
176 static const struct aspeed_clk_soc_data ast2400_data = {
177 	.div_table = ast2400_div_table,
178 	.eclk_div_table = ast2400_div_table,
179 	.mac_div_table = ast2400_div_table,
180 	.calc_pll = aspeed_ast2400_calc_pll,
181 };
182 
183 static int aspeed_clk_is_enabled(struct clk_hw *hw)
184 {
185 	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
186 	u32 clk = BIT(gate->clock_idx);
187 	u32 rst = BIT(gate->reset_idx);
188 	u32 enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
189 	u32 reg;
190 
191 	/*
192 	 * If the IP is in reset, treat the clock as not enabled,
193 	 * this happens with some clocks such as the USB one when
194 	 * coming from cold reset. Without this, aspeed_clk_enable()
195 	 * will fail to lift the reset.
196 	 */
197 	if (gate->reset_idx >= 0) {
198 		regmap_read(gate->map, ASPEED_RESET_CTRL, &reg);
199 		if (reg & rst)
200 			return 0;
201 	}
202 
203 	regmap_read(gate->map, ASPEED_CLK_STOP_CTRL, &reg);
204 
205 	return ((reg & clk) == enval) ? 1 : 0;
206 }
207 
208 static int aspeed_clk_enable(struct clk_hw *hw)
209 {
210 	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
211 	unsigned long flags;
212 	u32 clk = BIT(gate->clock_idx);
213 	u32 rst = BIT(gate->reset_idx);
214 	u32 enval;
215 
216 	spin_lock_irqsave(gate->lock, flags);
217 
218 	if (aspeed_clk_is_enabled(hw)) {
219 		spin_unlock_irqrestore(gate->lock, flags);
220 		return 0;
221 	}
222 
223 	if (gate->reset_idx >= 0) {
224 		/* Put IP in reset */
225 		regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, rst);
226 
227 		/* Delay 100us */
228 		udelay(100);
229 	}
230 
231 	/* Enable clock */
232 	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
233 	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
234 
235 	if (gate->reset_idx >= 0) {
236 		/* A delay of 10ms is specified by the ASPEED docs */
237 		mdelay(10);
238 
239 		/* Take IP out of reset */
240 		regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, 0);
241 	}
242 
243 	spin_unlock_irqrestore(gate->lock, flags);
244 
245 	return 0;
246 }
247 
248 static void aspeed_clk_disable(struct clk_hw *hw)
249 {
250 	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
251 	unsigned long flags;
252 	u32 clk = BIT(gate->clock_idx);
253 	u32 enval;
254 
255 	spin_lock_irqsave(gate->lock, flags);
256 
257 	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? clk : 0;
258 	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
259 
260 	spin_unlock_irqrestore(gate->lock, flags);
261 }
262 
263 static const struct clk_ops aspeed_clk_gate_ops = {
264 	.enable = aspeed_clk_enable,
265 	.disable = aspeed_clk_disable,
266 	.is_enabled = aspeed_clk_is_enabled,
267 };
268 
269 static const u8 aspeed_resets[] = {
270 	/* SCU04 resets */
271 	[ASPEED_RESET_XDMA]	= 25,
272 	[ASPEED_RESET_MCTP]	= 24,
273 	[ASPEED_RESET_ADC]	= 23,
274 	[ASPEED_RESET_JTAG_MASTER] = 22,
275 	[ASPEED_RESET_MIC]	= 18,
276 	[ASPEED_RESET_PWM]	=  9,
277 	[ASPEED_RESET_PECI]	= 10,
278 	[ASPEED_RESET_I2C]	=  2,
279 	[ASPEED_RESET_AHB]	=  1,
280 
281 	/*
282 	 * SCUD4 resets start at an offset to separate them from
283 	 * the SCU04 resets.
284 	 */
285 	[ASPEED_RESET_CRT1]	= ASPEED_RESET2_OFFSET + 5,
286 };
287 
288 static int aspeed_reset_deassert(struct reset_controller_dev *rcdev,
289 				 unsigned long id)
290 {
291 	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
292 	u32 reg = ASPEED_RESET_CTRL;
293 	u32 bit = aspeed_resets[id];
294 
295 	if (bit >= ASPEED_RESET2_OFFSET) {
296 		bit -= ASPEED_RESET2_OFFSET;
297 		reg = ASPEED_RESET_CTRL2;
298 	}
299 
300 	return regmap_update_bits(ar->map, reg, BIT(bit), 0);
301 }
302 
303 static int aspeed_reset_assert(struct reset_controller_dev *rcdev,
304 			       unsigned long id)
305 {
306 	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
307 	u32 reg = ASPEED_RESET_CTRL;
308 	u32 bit = aspeed_resets[id];
309 
310 	if (bit >= ASPEED_RESET2_OFFSET) {
311 		bit -= ASPEED_RESET2_OFFSET;
312 		reg = ASPEED_RESET_CTRL2;
313 	}
314 
315 	return regmap_update_bits(ar->map, reg, BIT(bit), BIT(bit));
316 }
317 
318 static int aspeed_reset_status(struct reset_controller_dev *rcdev,
319 			       unsigned long id)
320 {
321 	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
322 	u32 reg = ASPEED_RESET_CTRL;
323 	u32 bit = aspeed_resets[id];
324 	int ret, val;
325 
326 	if (bit >= ASPEED_RESET2_OFFSET) {
327 		bit -= ASPEED_RESET2_OFFSET;
328 		reg = ASPEED_RESET_CTRL2;
329 	}
330 
331 	ret = regmap_read(ar->map, reg, &val);
332 	if (ret)
333 		return ret;
334 
335 	return !!(val & BIT(bit));
336 }
337 
338 static const struct reset_control_ops aspeed_reset_ops = {
339 	.assert = aspeed_reset_assert,
340 	.deassert = aspeed_reset_deassert,
341 	.status = aspeed_reset_status,
342 };
343 
344 static struct clk_hw *aspeed_clk_hw_register_gate(struct device *dev,
345 		const char *name, const char *parent_name, unsigned long flags,
346 		struct regmap *map, u8 clock_idx, u8 reset_idx,
347 		u8 clk_gate_flags, spinlock_t *lock)
348 {
349 	struct aspeed_clk_gate *gate;
350 	struct clk_init_data init;
351 	struct clk_hw *hw;
352 	int ret;
353 
354 	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
355 	if (!gate)
356 		return ERR_PTR(-ENOMEM);
357 
358 	init.name = name;
359 	init.ops = &aspeed_clk_gate_ops;
360 	init.flags = flags;
361 	init.parent_names = parent_name ? &parent_name : NULL;
362 	init.num_parents = parent_name ? 1 : 0;
363 
364 	gate->map = map;
365 	gate->clock_idx = clock_idx;
366 	gate->reset_idx = reset_idx;
367 	gate->flags = clk_gate_flags;
368 	gate->lock = lock;
369 	gate->hw.init = &init;
370 
371 	hw = &gate->hw;
372 	ret = clk_hw_register(dev, hw);
373 	if (ret) {
374 		kfree(gate);
375 		hw = ERR_PTR(ret);
376 	}
377 
378 	return hw;
379 }
380 
381 static int aspeed_clk_probe(struct platform_device *pdev)
382 {
383 	const struct aspeed_clk_soc_data *soc_data;
384 	struct device *dev = &pdev->dev;
385 	struct aspeed_reset *ar;
386 	struct regmap *map;
387 	struct clk_hw *hw;
388 	u32 val, rate;
389 	int i, ret;
390 
391 	map = syscon_node_to_regmap(dev->of_node);
392 	if (IS_ERR(map)) {
393 		dev_err(dev, "no syscon regmap\n");
394 		return PTR_ERR(map);
395 	}
396 
397 	ar = devm_kzalloc(dev, sizeof(*ar), GFP_KERNEL);
398 	if (!ar)
399 		return -ENOMEM;
400 
401 	ar->map = map;
402 	ar->rcdev.owner = THIS_MODULE;
403 	ar->rcdev.nr_resets = ARRAY_SIZE(aspeed_resets);
404 	ar->rcdev.ops = &aspeed_reset_ops;
405 	ar->rcdev.of_node = dev->of_node;
406 
407 	ret = devm_reset_controller_register(dev, &ar->rcdev);
408 	if (ret) {
409 		dev_err(dev, "could not register reset controller\n");
410 		return ret;
411 	}
412 
413 	/* SoC generations share common layouts but have different divisors */
414 	soc_data = of_device_get_match_data(dev);
415 	if (!soc_data) {
416 		dev_err(dev, "no match data for platform\n");
417 		return -EINVAL;
418 	}
419 
420 	/* UART clock div13 setting */
421 	regmap_read(map, ASPEED_MISC_CTRL, &val);
422 	if (val & UART_DIV13_EN)
423 		rate = 24000000 / 13;
424 	else
425 		rate = 24000000;
426 	/* TODO: Find the parent data for the uart clock */
427 	hw = clk_hw_register_fixed_rate(dev, "uart", NULL, 0, rate);
428 	if (IS_ERR(hw))
429 		return PTR_ERR(hw);
430 	aspeed_clk_data->hws[ASPEED_CLK_UART] = hw;
431 
432 	/*
433 	 * Memory controller (M-PLL) PLL. This clock is configured by the
434 	 * bootloader, and is exposed to Linux as a read-only clock rate.
435 	 */
436 	regmap_read(map, ASPEED_MPLL_PARAM, &val);
437 	hw = soc_data->calc_pll("mpll", val);
438 	if (IS_ERR(hw))
439 		return PTR_ERR(hw);
440 	aspeed_clk_data->hws[ASPEED_CLK_MPLL] =	hw;
441 
442 	/* SD/SDIO clock divider and gate */
443 	hw = clk_hw_register_gate(dev, "sd_extclk_gate", "hpll", 0,
444 				  scu_base + ASPEED_CLK_SELECTION, 15, 0,
445 				  &aspeed_clk_lock);
446 	if (IS_ERR(hw))
447 		return PTR_ERR(hw);
448 	hw = clk_hw_register_divider_table(dev, "sd_extclk", "sd_extclk_gate",
449 			0, scu_base + ASPEED_CLK_SELECTION, 12, 3, 0,
450 			soc_data->div_table,
451 			&aspeed_clk_lock);
452 	if (IS_ERR(hw))
453 		return PTR_ERR(hw);
454 	aspeed_clk_data->hws[ASPEED_CLK_SDIO] = hw;
455 
456 	/* MAC AHB bus clock divider */
457 	hw = clk_hw_register_divider_table(dev, "mac", "hpll", 0,
458 			scu_base + ASPEED_CLK_SELECTION, 16, 3, 0,
459 			soc_data->mac_div_table,
460 			&aspeed_clk_lock);
461 	if (IS_ERR(hw))
462 		return PTR_ERR(hw);
463 	aspeed_clk_data->hws[ASPEED_CLK_MAC] = hw;
464 
465 	/* LPC Host (LHCLK) clock divider */
466 	hw = clk_hw_register_divider_table(dev, "lhclk", "hpll", 0,
467 			scu_base + ASPEED_CLK_SELECTION, 20, 3, 0,
468 			soc_data->div_table,
469 			&aspeed_clk_lock);
470 	if (IS_ERR(hw))
471 		return PTR_ERR(hw);
472 	aspeed_clk_data->hws[ASPEED_CLK_LHCLK] = hw;
473 
474 	/* P-Bus (BCLK) clock divider */
475 	hw = clk_hw_register_divider_table(dev, "bclk", "hpll", 0,
476 			scu_base + ASPEED_CLK_SELECTION_2, 0, 2, 0,
477 			soc_data->div_table,
478 			&aspeed_clk_lock);
479 	if (IS_ERR(hw))
480 		return PTR_ERR(hw);
481 	aspeed_clk_data->hws[ASPEED_CLK_BCLK] = hw;
482 
483 	/* Fixed 24MHz clock */
484 	hw = clk_hw_register_fixed_rate(NULL, "fixed-24m", "clkin",
485 					0, 24000000);
486 	if (IS_ERR(hw))
487 		return PTR_ERR(hw);
488 	aspeed_clk_data->hws[ASPEED_CLK_24M] = hw;
489 
490 	hw = clk_hw_register_mux(dev, "eclk-mux", eclk_parent_names,
491 				 ARRAY_SIZE(eclk_parent_names), 0,
492 				 scu_base + ASPEED_CLK_SELECTION, 2, 0x3, 0,
493 				 &aspeed_clk_lock);
494 	if (IS_ERR(hw))
495 		return PTR_ERR(hw);
496 	aspeed_clk_data->hws[ASPEED_CLK_ECLK_MUX] = hw;
497 
498 	hw = clk_hw_register_divider_table(dev, "eclk", "eclk-mux", 0,
499 					   scu_base + ASPEED_CLK_SELECTION, 28,
500 					   3, 0, soc_data->eclk_div_table,
501 					   &aspeed_clk_lock);
502 	if (IS_ERR(hw))
503 		return PTR_ERR(hw);
504 	aspeed_clk_data->hws[ASPEED_CLK_ECLK] = hw;
505 
506 	/*
507 	 * TODO: There are a number of clocks that not included in this driver
508 	 * as more information is required:
509 	 *   D2-PLL
510 	 *   D-PLL
511 	 *   YCLK
512 	 *   RGMII
513 	 *   RMII
514 	 *   UART[1..5] clock source mux
515 	 */
516 
517 	for (i = 0; i < ARRAY_SIZE(aspeed_gates); i++) {
518 		const struct aspeed_gate_data *gd = &aspeed_gates[i];
519 		u32 gate_flags;
520 
521 		/* Special case: the USB port 1 clock (bit 14) is always
522 		 * working the opposite way from the other ones.
523 		 */
524 		gate_flags = (gd->clock_idx == 14) ? 0 : CLK_GATE_SET_TO_DISABLE;
525 		hw = aspeed_clk_hw_register_gate(dev,
526 				gd->name,
527 				gd->parent_name,
528 				gd->flags,
529 				map,
530 				gd->clock_idx,
531 				gd->reset_idx,
532 				gate_flags,
533 				&aspeed_clk_lock);
534 		if (IS_ERR(hw))
535 			return PTR_ERR(hw);
536 		aspeed_clk_data->hws[i] = hw;
537 	}
538 
539 	return 0;
540 };
541 
542 static const struct of_device_id aspeed_clk_dt_ids[] = {
543 	{ .compatible = "aspeed,ast2400-scu", .data = &ast2400_data },
544 	{ .compatible = "aspeed,ast2500-scu", .data = &ast2500_data },
545 	{ }
546 };
547 
548 static struct platform_driver aspeed_clk_driver = {
549 	.probe  = aspeed_clk_probe,
550 	.driver = {
551 		.name = "aspeed-clk",
552 		.of_match_table = aspeed_clk_dt_ids,
553 		.suppress_bind_attrs = true,
554 	},
555 };
556 builtin_platform_driver(aspeed_clk_driver);
557 
558 static void __init aspeed_ast2400_cc(struct regmap *map)
559 {
560 	struct clk_hw *hw;
561 	u32 val, div, clkin, hpll;
562 	const u16 hpll_rates[][4] = {
563 		{384, 360, 336, 408},
564 		{400, 375, 350, 425},
565 	};
566 	int rate;
567 
568 	/*
569 	 * CLKIN is the crystal oscillator, 24, 48 or 25MHz selected by
570 	 * strapping
571 	 */
572 	regmap_read(map, ASPEED_STRAP, &val);
573 	rate = (val >> 8) & 3;
574 	if (val & CLKIN_25MHZ_EN) {
575 		clkin = 25000000;
576 		hpll = hpll_rates[1][rate];
577 	} else if (val & AST2400_CLK_SOURCE_SEL) {
578 		clkin = 48000000;
579 		hpll = hpll_rates[0][rate];
580 	} else {
581 		clkin = 24000000;
582 		hpll = hpll_rates[0][rate];
583 	}
584 	hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, clkin);
585 	pr_debug("clkin @%u MHz\n", clkin / 1000000);
586 
587 	/*
588 	 * High-speed PLL clock derived from the crystal. This the CPU clock,
589 	 * and we assume that it is enabled. It can be configured through the
590 	 * HPLL_PARAM register, or set to a specified frequency by strapping.
591 	 */
592 	regmap_read(map, ASPEED_HPLL_PARAM, &val);
593 	if (val & AST2400_HPLL_PROGRAMMED)
594 		hw = aspeed_ast2400_calc_pll("hpll", val);
595 	else
596 		hw = clk_hw_register_fixed_rate(NULL, "hpll", "clkin", 0,
597 				hpll * 1000000);
598 
599 	aspeed_clk_data->hws[ASPEED_CLK_HPLL] = hw;
600 
601 	/*
602 	 * Strap bits 11:10 define the CPU/AHB clock frequency ratio (aka HCLK)
603 	 *   00: Select CPU:AHB = 1:1
604 	 *   01: Select CPU:AHB = 2:1
605 	 *   10: Select CPU:AHB = 4:1
606 	 *   11: Select CPU:AHB = 3:1
607 	 */
608 	regmap_read(map, ASPEED_STRAP, &val);
609 	val = (val >> 10) & 0x3;
610 	div = val + 1;
611 	if (div == 3)
612 		div = 4;
613 	else if (div == 4)
614 		div = 3;
615 	hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
616 	aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
617 
618 	/* APB clock clock selection register SCU08 (aka PCLK) */
619 	hw = clk_hw_register_divider_table(NULL, "apb", "hpll", 0,
620 			scu_base + ASPEED_CLK_SELECTION, 23, 3, 0,
621 			ast2400_div_table,
622 			&aspeed_clk_lock);
623 	aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
624 }
625 
626 static void __init aspeed_ast2500_cc(struct regmap *map)
627 {
628 	struct clk_hw *hw;
629 	u32 val, freq, div;
630 
631 	/* CLKIN is the crystal oscillator, 24 or 25MHz selected by strapping */
632 	regmap_read(map, ASPEED_STRAP, &val);
633 	if (val & CLKIN_25MHZ_EN)
634 		freq = 25000000;
635 	else
636 		freq = 24000000;
637 	hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, freq);
638 	pr_debug("clkin @%u MHz\n", freq / 1000000);
639 
640 	/*
641 	 * High-speed PLL clock derived from the crystal. This the CPU clock,
642 	 * and we assume that it is enabled
643 	 */
644 	regmap_read(map, ASPEED_HPLL_PARAM, &val);
645 	aspeed_clk_data->hws[ASPEED_CLK_HPLL] = aspeed_ast2500_calc_pll("hpll", val);
646 
647 	/* Strap bits 11:9 define the AXI/AHB clock frequency ratio (aka HCLK)*/
648 	regmap_read(map, ASPEED_STRAP, &val);
649 	val = (val >> 9) & 0x7;
650 	WARN(val == 0, "strapping is zero: cannot determine ahb clock");
651 	div = 2 * (val + 1);
652 	hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
653 	aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
654 
655 	/* APB clock clock selection register SCU08 (aka PCLK) */
656 	regmap_read(map, ASPEED_CLK_SELECTION, &val);
657 	val = (val >> 23) & 0x7;
658 	div = 4 * (val + 1);
659 	hw = clk_hw_register_fixed_factor(NULL, "apb", "hpll", 0, 1, div);
660 	aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
661 };
662 
663 static void __init aspeed_cc_init(struct device_node *np)
664 {
665 	struct regmap *map;
666 	u32 val;
667 	int ret;
668 	int i;
669 
670 	scu_base = of_iomap(np, 0);
671 	if (!scu_base)
672 		return;
673 
674 	aspeed_clk_data = kzalloc(struct_size(aspeed_clk_data, hws,
675 					      ASPEED_NUM_CLKS),
676 				  GFP_KERNEL);
677 	if (!aspeed_clk_data)
678 		return;
679 
680 	/*
681 	 * This way all clocks fetched before the platform device probes,
682 	 * except those we assign here for early use, will be deferred.
683 	 */
684 	for (i = 0; i < ASPEED_NUM_CLKS; i++)
685 		aspeed_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);
686 
687 	map = syscon_node_to_regmap(np);
688 	if (IS_ERR(map)) {
689 		pr_err("no syscon regmap\n");
690 		return;
691 	}
692 	/*
693 	 * We check that the regmap works on this very first access,
694 	 * but as this is an MMIO-backed regmap, subsequent regmap
695 	 * access is not going to fail and we skip error checks from
696 	 * this point.
697 	 */
698 	ret = regmap_read(map, ASPEED_STRAP, &val);
699 	if (ret) {
700 		pr_err("failed to read strapping register\n");
701 		return;
702 	}
703 
704 	if (of_device_is_compatible(np, "aspeed,ast2400-scu"))
705 		aspeed_ast2400_cc(map);
706 	else if (of_device_is_compatible(np, "aspeed,ast2500-scu"))
707 		aspeed_ast2500_cc(map);
708 	else
709 		pr_err("unknown platform, failed to add clocks\n");
710 
711 	aspeed_clk_data->num = ASPEED_NUM_CLKS;
712 	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, aspeed_clk_data);
713 	if (ret)
714 		pr_err("failed to add DT provider: %d\n", ret);
715 };
716 CLK_OF_DECLARE_DRIVER(aspeed_cc_g5, "aspeed,ast2500-scu", aspeed_cc_init);
717 CLK_OF_DECLARE_DRIVER(aspeed_cc_g4, "aspeed,ast2400-scu", aspeed_cc_init);
718