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.h>
8#include <linux/of_address.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		38
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_MAC_CLK_DLY	0x48
32#define ASPEED_STRAP		0x70
33#define  CLKIN_25MHZ_EN		BIT(23)
34#define  AST2400_CLK_SOURCE_SEL	BIT(18)
35#define ASPEED_CLK_SELECTION_2	0xd8
36#define ASPEED_RESET_CTRL2	0xd4
37
38/* Globally visible clocks */
39static DEFINE_SPINLOCK(aspeed_clk_lock);
40
41/* Keeps track of all clocks */
42static struct clk_hw_onecell_data *aspeed_clk_data;
43
44static void __iomem *scu_base;
45
46/* TODO: ask Aspeed about the actual parent data */
47static const struct aspeed_gate_data aspeed_gates[] = {
48	/*				 clk rst   name			parent	flags */
49	[ASPEED_CLK_GATE_ECLK] =	{  0,  6, "eclk-gate",		"eclk",	0 }, /* Video Engine */
50	[ASPEED_CLK_GATE_GCLK] =	{  1,  7, "gclk-gate",		NULL,	0 }, /* 2D engine */
51	[ASPEED_CLK_GATE_MCLK] =	{  2, -1, "mclk-gate",		"mpll",	CLK_IS_CRITICAL }, /* SDRAM */
52	[ASPEED_CLK_GATE_VCLK] =	{  3, -1, "vclk-gate",		NULL,	0 }, /* Video Capture */
53	[ASPEED_CLK_GATE_BCLK] =	{  4,  8, "bclk-gate",		"bclk",	CLK_IS_CRITICAL }, /* PCIe/PCI */
54	[ASPEED_CLK_GATE_DCLK] =	{  5, -1, "dclk-gate",		NULL,	CLK_IS_CRITICAL }, /* DAC */
55	[ASPEED_CLK_GATE_REFCLK] =	{  6, -1, "refclk-gate",	"clkin", CLK_IS_CRITICAL },
56	[ASPEED_CLK_GATE_USBPORT2CLK] =	{  7,  3, "usb-port2-gate",	NULL,	0 }, /* USB2.0 Host port 2 */
57	[ASPEED_CLK_GATE_LCLK] =	{  8,  5, "lclk-gate",		NULL,	0 }, /* LPC */
58	[ASPEED_CLK_GATE_USBUHCICLK] =	{  9, 15, "usb-uhci-gate",	NULL,	0 }, /* USB1.1 (requires port 2 enabled) */
59	[ASPEED_CLK_GATE_D1CLK] =	{ 10, 13, "d1clk-gate",		NULL,	0 }, /* GFX CRT */
60	[ASPEED_CLK_GATE_YCLK] =	{ 13,  4, "yclk-gate",		NULL,	0 }, /* HAC */
61	[ASPEED_CLK_GATE_USBPORT1CLK] = { 14, 14, "usb-port1-gate",	NULL,	0 }, /* USB2 hub/USB2 host port 1/USB1.1 dev */
62	[ASPEED_CLK_GATE_UART1CLK] =	{ 15, -1, "uart1clk-gate",	"uart",	0 }, /* UART1 */
63	[ASPEED_CLK_GATE_UART2CLK] =	{ 16, -1, "uart2clk-gate",	"uart",	0 }, /* UART2 */
64	[ASPEED_CLK_GATE_UART5CLK] =	{ 17, -1, "uart5clk-gate",	"uart",	0 }, /* UART5 */
65	[ASPEED_CLK_GATE_ESPICLK] =	{ 19, -1, "espiclk-gate",	NULL,	0 }, /* eSPI */
66	[ASPEED_CLK_GATE_MAC1CLK] =	{ 20, 11, "mac1clk-gate",	"mac",	0 }, /* MAC1 */
67	[ASPEED_CLK_GATE_MAC2CLK] =	{ 21, 12, "mac2clk-gate",	"mac",	0 }, /* MAC2 */
68	[ASPEED_CLK_GATE_RSACLK] =	{ 24, -1, "rsaclk-gate",	NULL,	0 }, /* RSA */
69	[ASPEED_CLK_GATE_UART3CLK] =	{ 25, -1, "uart3clk-gate",	"uart",	0 }, /* UART3 */
70	[ASPEED_CLK_GATE_UART4CLK] =	{ 26, -1, "uart4clk-gate",	"uart",	0 }, /* UART4 */
71	[ASPEED_CLK_GATE_SDCLK] =	{ 27, 16, "sdclk-gate",		NULL,	0 }, /* SDIO/SD */
72	[ASPEED_CLK_GATE_LHCCLK] =	{ 28, -1, "lhclk-gate",		"lhclk", 0 }, /* LPC master/LPC+ */
73};
74
75static const char * const eclk_parent_names[] = {
76	"mpll",
77	"hpll",
78	"dpll",
79};
80
81static const struct clk_div_table ast2500_eclk_div_table[] = {
82	{ 0x0, 2 },
83	{ 0x1, 2 },
84	{ 0x2, 3 },
85	{ 0x3, 4 },
86	{ 0x4, 5 },
87	{ 0x5, 6 },
88	{ 0x6, 7 },
89	{ 0x7, 8 },
90	{ 0 }
91};
92
93static const struct clk_div_table ast2500_mac_div_table[] = {
94	{ 0x0, 4 }, /* Yep, really. Aspeed confirmed this is correct */
95	{ 0x1, 4 },
96	{ 0x2, 6 },
97	{ 0x3, 8 },
98	{ 0x4, 10 },
99	{ 0x5, 12 },
100	{ 0x6, 14 },
101	{ 0x7, 16 },
102	{ 0 }
103};
104
105static const struct clk_div_table ast2400_div_table[] = {
106	{ 0x0, 2 },
107	{ 0x1, 4 },
108	{ 0x2, 6 },
109	{ 0x3, 8 },
110	{ 0x4, 10 },
111	{ 0x5, 12 },
112	{ 0x6, 14 },
113	{ 0x7, 16 },
114	{ 0 }
115};
116
117static const struct clk_div_table ast2500_div_table[] = {
118	{ 0x0, 4 },
119	{ 0x1, 8 },
120	{ 0x2, 12 },
121	{ 0x3, 16 },
122	{ 0x4, 20 },
123	{ 0x5, 24 },
124	{ 0x6, 28 },
125	{ 0x7, 32 },
126	{ 0 }
127};
128
129static struct clk_hw *aspeed_ast2400_calc_pll(const char *name, u32 val)
130{
131	unsigned int mult, div;
132
133	if (val & AST2400_HPLL_BYPASS_EN) {
134		/* Pass through mode */
135		mult = div = 1;
136	} else {
137		/* F = 24Mhz * (2-OD) * [(N + 2) / (D + 1)] */
138		u32 n = (val >> 5) & 0x3f;
139		u32 od = (val >> 4) & 0x1;
140		u32 d = val & 0xf;
141
142		mult = (2 - od) * (n + 2);
143		div = d + 1;
144	}
145	return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
146			mult, div);
147};
148
149static struct clk_hw *aspeed_ast2500_calc_pll(const char *name, u32 val)
150{
151	unsigned int mult, div;
152
153	if (val & AST2500_HPLL_BYPASS_EN) {
154		/* Pass through mode */
155		mult = div = 1;
156	} else {
157		/* F = clkin * [(M+1) / (N+1)] / (P + 1) */
158		u32 p = (val >> 13) & 0x3f;
159		u32 m = (val >> 5) & 0xff;
160		u32 n = val & 0x1f;
161
162		mult = (m + 1) / (n + 1);
163		div = p + 1;
164	}
165
166	return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
167			mult, div);
168}
169
170static const struct aspeed_clk_soc_data ast2500_data = {
171	.div_table = ast2500_div_table,
172	.eclk_div_table = ast2500_eclk_div_table,
173	.mac_div_table = ast2500_mac_div_table,
174	.calc_pll = aspeed_ast2500_calc_pll,
175};
176
177static const struct aspeed_clk_soc_data ast2400_data = {
178	.div_table = ast2400_div_table,
179	.eclk_div_table = ast2400_div_table,
180	.mac_div_table = ast2400_div_table,
181	.calc_pll = aspeed_ast2400_calc_pll,
182};
183
184static int aspeed_clk_is_enabled(struct clk_hw *hw)
185{
186	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
187	u32 clk = BIT(gate->clock_idx);
188	u32 rst = BIT(gate->reset_idx);
189	u32 enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
190	u32 reg;
191
192	/*
193	 * If the IP is in reset, treat the clock as not enabled,
194	 * this happens with some clocks such as the USB one when
195	 * coming from cold reset. Without this, aspeed_clk_enable()
196	 * will fail to lift the reset.
197	 */
198	if (gate->reset_idx >= 0) {
199		regmap_read(gate->map, ASPEED_RESET_CTRL, &reg);
200		if (reg & rst)
201			return 0;
202	}
203
204	regmap_read(gate->map, ASPEED_CLK_STOP_CTRL, &reg);
205
206	return ((reg & clk) == enval) ? 1 : 0;
207}
208
209static int aspeed_clk_enable(struct clk_hw *hw)
210{
211	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
212	unsigned long flags;
213	u32 clk = BIT(gate->clock_idx);
214	u32 rst = BIT(gate->reset_idx);
215	u32 enval;
216
217	spin_lock_irqsave(gate->lock, flags);
218
219	if (aspeed_clk_is_enabled(hw)) {
220		spin_unlock_irqrestore(gate->lock, flags);
221		return 0;
222	}
223
224	if (gate->reset_idx >= 0) {
225		/* Put IP in reset */
226		regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, rst);
227
228		/* Delay 100us */
229		udelay(100);
230	}
231
232	/* Enable clock */
233	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
234	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
235
236	if (gate->reset_idx >= 0) {
237		/* A delay of 10ms is specified by the ASPEED docs */
238		mdelay(10);
239
240		/* Take IP out of reset */
241		regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, 0);
242	}
243
244	spin_unlock_irqrestore(gate->lock, flags);
245
246	return 0;
247}
248
249static void aspeed_clk_disable(struct clk_hw *hw)
250{
251	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
252	unsigned long flags;
253	u32 clk = BIT(gate->clock_idx);
254	u32 enval;
255
256	spin_lock_irqsave(gate->lock, flags);
257
258	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? clk : 0;
259	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
260
261	spin_unlock_irqrestore(gate->lock, flags);
262}
263
264static const struct clk_ops aspeed_clk_gate_ops = {
265	.enable = aspeed_clk_enable,
266	.disable = aspeed_clk_disable,
267	.is_enabled = aspeed_clk_is_enabled,
268};
269
270static const u8 aspeed_resets[] = {
271	/* SCU04 resets */
272	[ASPEED_RESET_XDMA]	= 25,
273	[ASPEED_RESET_MCTP]	= 24,
274	[ASPEED_RESET_ADC]	= 23,
275	[ASPEED_RESET_JTAG_MASTER] = 22,
276	[ASPEED_RESET_MIC]	= 18,
277	[ASPEED_RESET_PWM]	=  9,
278	[ASPEED_RESET_PECI]	= 10,
279	[ASPEED_RESET_I2C]	=  2,
280	[ASPEED_RESET_AHB]	=  1,
281
282	/*
283	 * SCUD4 resets start at an offset to separate them from
284	 * the SCU04 resets.
285	 */
286	[ASPEED_RESET_CRT1]	= ASPEED_RESET2_OFFSET + 5,
287};
288
289static int aspeed_reset_deassert(struct reset_controller_dev *rcdev,
290				 unsigned long id)
291{
292	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
293	u32 reg = ASPEED_RESET_CTRL;
294	u32 bit = aspeed_resets[id];
295
296	if (bit >= ASPEED_RESET2_OFFSET) {
297		bit -= ASPEED_RESET2_OFFSET;
298		reg = ASPEED_RESET_CTRL2;
299	}
300
301	return regmap_update_bits(ar->map, reg, BIT(bit), 0);
302}
303
304static int aspeed_reset_assert(struct reset_controller_dev *rcdev,
305			       unsigned long id)
306{
307	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
308	u32 reg = ASPEED_RESET_CTRL;
309	u32 bit = aspeed_resets[id];
310
311	if (bit >= ASPEED_RESET2_OFFSET) {
312		bit -= ASPEED_RESET2_OFFSET;
313		reg = ASPEED_RESET_CTRL2;
314	}
315
316	return regmap_update_bits(ar->map, reg, BIT(bit), BIT(bit));
317}
318
319static int aspeed_reset_status(struct reset_controller_dev *rcdev,
320			       unsigned long id)
321{
322	struct aspeed_reset *ar = to_aspeed_reset(rcdev);
323	u32 reg = ASPEED_RESET_CTRL;
324	u32 bit = aspeed_resets[id];
325	int ret, val;
326
327	if (bit >= ASPEED_RESET2_OFFSET) {
328		bit -= ASPEED_RESET2_OFFSET;
329		reg = ASPEED_RESET_CTRL2;
330	}
331
332	ret = regmap_read(ar->map, reg, &val);
333	if (ret)
334		return ret;
335
336	return !!(val & BIT(bit));
337}
338
339static const struct reset_control_ops aspeed_reset_ops = {
340	.assert = aspeed_reset_assert,
341	.deassert = aspeed_reset_deassert,
342	.status = aspeed_reset_status,
343};
344
345static struct clk_hw *aspeed_clk_hw_register_gate(struct device *dev,
346		const char *name, const char *parent_name, unsigned long flags,
347		struct regmap *map, u8 clock_idx, u8 reset_idx,
348		u8 clk_gate_flags, spinlock_t *lock)
349{
350	struct aspeed_clk_gate *gate;
351	struct clk_init_data init;
352	struct clk_hw *hw;
353	int ret;
354
355	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
356	if (!gate)
357		return ERR_PTR(-ENOMEM);
358
359	init.name = name;
360	init.ops = &aspeed_clk_gate_ops;
361	init.flags = flags;
362	init.parent_names = parent_name ? &parent_name : NULL;
363	init.num_parents = parent_name ? 1 : 0;
364
365	gate->map = map;
366	gate->clock_idx = clock_idx;
367	gate->reset_idx = reset_idx;
368	gate->flags = clk_gate_flags;
369	gate->lock = lock;
370	gate->hw.init = &init;
371
372	hw = &gate->hw;
373	ret = clk_hw_register(dev, hw);
374	if (ret) {
375		kfree(gate);
376		hw = ERR_PTR(ret);
377	}
378
379	return hw;
380}
381
382static int aspeed_clk_probe(struct platform_device *pdev)
383{
384	const struct aspeed_clk_soc_data *soc_data;
385	struct device *dev = &pdev->dev;
386	struct aspeed_reset *ar;
387	struct regmap *map;
388	struct clk_hw *hw;
389	u32 val, rate;
390	int i, ret;
391
392	map = syscon_node_to_regmap(dev->of_node);
393	if (IS_ERR(map)) {
394		dev_err(dev, "no syscon regmap\n");
395		return PTR_ERR(map);
396	}
397
398	ar = devm_kzalloc(dev, sizeof(*ar), GFP_KERNEL);
399	if (!ar)
400		return -ENOMEM;
401
402	ar->map = map;
403	ar->rcdev.owner = THIS_MODULE;
404	ar->rcdev.nr_resets = ARRAY_SIZE(aspeed_resets);
405	ar->rcdev.ops = &aspeed_reset_ops;
406	ar->rcdev.of_node = dev->of_node;
407
408	ret = devm_reset_controller_register(dev, &ar->rcdev);
409	if (ret) {
410		dev_err(dev, "could not register reset controller\n");
411		return ret;
412	}
413
414	/* SoC generations share common layouts but have different divisors */
415	soc_data = of_device_get_match_data(dev);
416	if (!soc_data) {
417		dev_err(dev, "no match data for platform\n");
418		return -EINVAL;
419	}
420
421	/* UART clock div13 setting */
422	regmap_read(map, ASPEED_MISC_CTRL, &val);
423	if (val & UART_DIV13_EN)
424		rate = 24000000 / 13;
425	else
426		rate = 24000000;
427	/* TODO: Find the parent data for the uart clock */
428	hw = clk_hw_register_fixed_rate(dev, "uart", NULL, 0, rate);
429	if (IS_ERR(hw))
430		return PTR_ERR(hw);
431	aspeed_clk_data->hws[ASPEED_CLK_UART] = hw;
432
433	/*
434	 * Memory controller (M-PLL) PLL. This clock is configured by the
435	 * bootloader, and is exposed to Linux as a read-only clock rate.
436	 */
437	regmap_read(map, ASPEED_MPLL_PARAM, &val);
438	hw = soc_data->calc_pll("mpll", val);
439	if (IS_ERR(hw))
440		return PTR_ERR(hw);
441	aspeed_clk_data->hws[ASPEED_CLK_MPLL] =	hw;
442
443	/* SD/SDIO clock divider and gate */
444	hw = clk_hw_register_gate(dev, "sd_extclk_gate", "hpll", 0,
445				  scu_base + ASPEED_CLK_SELECTION, 15, 0,
446				  &aspeed_clk_lock);
447	if (IS_ERR(hw))
448		return PTR_ERR(hw);
449	hw = clk_hw_register_divider_table(dev, "sd_extclk", "sd_extclk_gate",
450			0, scu_base + ASPEED_CLK_SELECTION, 12, 3, 0,
451			soc_data->div_table,
452			&aspeed_clk_lock);
453	if (IS_ERR(hw))
454		return PTR_ERR(hw);
455	aspeed_clk_data->hws[ASPEED_CLK_SDIO] = hw;
456
457	/* MAC AHB bus clock divider */
458	hw = clk_hw_register_divider_table(dev, "mac", "hpll", 0,
459			scu_base + ASPEED_CLK_SELECTION, 16, 3, 0,
460			soc_data->mac_div_table,
461			&aspeed_clk_lock);
462	if (IS_ERR(hw))
463		return PTR_ERR(hw);
464	aspeed_clk_data->hws[ASPEED_CLK_MAC] = hw;
465
466	if (of_device_is_compatible(pdev->dev.of_node, "aspeed,ast2500-scu")) {
467		/* RMII 50MHz RCLK */
468		hw = clk_hw_register_fixed_rate(dev, "mac12rclk", "hpll", 0,
469						50000000);
470		if (IS_ERR(hw))
471			return PTR_ERR(hw);
472
473		/* RMII1 50MHz (RCLK) output enable */
474		hw = clk_hw_register_gate(dev, "mac1rclk", "mac12rclk", 0,
475				scu_base + ASPEED_MAC_CLK_DLY, 29, 0,
476				&aspeed_clk_lock);
477		if (IS_ERR(hw))
478			return PTR_ERR(hw);
479		aspeed_clk_data->hws[ASPEED_CLK_MAC1RCLK] = hw;
480
481		/* RMII2 50MHz (RCLK) output enable */
482		hw = clk_hw_register_gate(dev, "mac2rclk", "mac12rclk", 0,
483				scu_base + ASPEED_MAC_CLK_DLY, 30, 0,
484				&aspeed_clk_lock);
485		if (IS_ERR(hw))
486			return PTR_ERR(hw);
487		aspeed_clk_data->hws[ASPEED_CLK_MAC2RCLK] = hw;
488	}
489
490	/* LPC Host (LHCLK) clock divider */
491	hw = clk_hw_register_divider_table(dev, "lhclk", "hpll", 0,
492			scu_base + ASPEED_CLK_SELECTION, 20, 3, 0,
493			soc_data->div_table,
494			&aspeed_clk_lock);
495	if (IS_ERR(hw))
496		return PTR_ERR(hw);
497	aspeed_clk_data->hws[ASPEED_CLK_LHCLK] = hw;
498
499	/* P-Bus (BCLK) clock divider */
500	hw = clk_hw_register_divider_table(dev, "bclk", "hpll", 0,
501			scu_base + ASPEED_CLK_SELECTION_2, 0, 2, 0,
502			soc_data->div_table,
503			&aspeed_clk_lock);
504	if (IS_ERR(hw))
505		return PTR_ERR(hw);
506	aspeed_clk_data->hws[ASPEED_CLK_BCLK] = hw;
507
508	/* Fixed 24MHz clock */
509	hw = clk_hw_register_fixed_rate(NULL, "fixed-24m", "clkin",
510					0, 24000000);
511	if (IS_ERR(hw))
512		return PTR_ERR(hw);
513	aspeed_clk_data->hws[ASPEED_CLK_24M] = hw;
514
515	hw = clk_hw_register_mux(dev, "eclk-mux", eclk_parent_names,
516				 ARRAY_SIZE(eclk_parent_names), 0,
517				 scu_base + ASPEED_CLK_SELECTION, 2, 0x3, 0,
518				 &aspeed_clk_lock);
519	if (IS_ERR(hw))
520		return PTR_ERR(hw);
521	aspeed_clk_data->hws[ASPEED_CLK_ECLK_MUX] = hw;
522
523	hw = clk_hw_register_divider_table(dev, "eclk", "eclk-mux", 0,
524					   scu_base + ASPEED_CLK_SELECTION, 28,
525					   3, 0, soc_data->eclk_div_table,
526					   &aspeed_clk_lock);
527	if (IS_ERR(hw))
528		return PTR_ERR(hw);
529	aspeed_clk_data->hws[ASPEED_CLK_ECLK] = hw;
530
531	/*
532	 * TODO: There are a number of clocks that not included in this driver
533	 * as more information is required:
534	 *   D2-PLL
535	 *   D-PLL
536	 *   YCLK
537	 *   RGMII
538	 *   RMII
539	 *   UART[1..5] clock source mux
540	 */
541
542	for (i = 0; i < ARRAY_SIZE(aspeed_gates); i++) {
543		const struct aspeed_gate_data *gd = &aspeed_gates[i];
544		u32 gate_flags;
545
546		/* Special case: the USB port 1 clock (bit 14) is always
547		 * working the opposite way from the other ones.
548		 */
549		gate_flags = (gd->clock_idx == 14) ? 0 : CLK_GATE_SET_TO_DISABLE;
550		hw = aspeed_clk_hw_register_gate(dev,
551				gd->name,
552				gd->parent_name,
553				gd->flags,
554				map,
555				gd->clock_idx,
556				gd->reset_idx,
557				gate_flags,
558				&aspeed_clk_lock);
559		if (IS_ERR(hw))
560			return PTR_ERR(hw);
561		aspeed_clk_data->hws[i] = hw;
562	}
563
564	return 0;
565};
566
567static const struct of_device_id aspeed_clk_dt_ids[] = {
568	{ .compatible = "aspeed,ast2400-scu", .data = &ast2400_data },
569	{ .compatible = "aspeed,ast2500-scu", .data = &ast2500_data },
570	{ }
571};
572
573static struct platform_driver aspeed_clk_driver = {
574	.probe  = aspeed_clk_probe,
575	.driver = {
576		.name = "aspeed-clk",
577		.of_match_table = aspeed_clk_dt_ids,
578		.suppress_bind_attrs = true,
579	},
580};
581builtin_platform_driver(aspeed_clk_driver);
582
583static void __init aspeed_ast2400_cc(struct regmap *map)
584{
585	struct clk_hw *hw;
586	u32 val, div, clkin, hpll;
587	const u16 hpll_rates[][4] = {
588		{384, 360, 336, 408},
589		{400, 375, 350, 425},
590	};
591	int rate;
592
593	/*
594	 * CLKIN is the crystal oscillator, 24, 48 or 25MHz selected by
595	 * strapping
596	 */
597	regmap_read(map, ASPEED_STRAP, &val);
598	rate = (val >> 8) & 3;
599	if (val & CLKIN_25MHZ_EN) {
600		clkin = 25000000;
601		hpll = hpll_rates[1][rate];
602	} else if (val & AST2400_CLK_SOURCE_SEL) {
603		clkin = 48000000;
604		hpll = hpll_rates[0][rate];
605	} else {
606		clkin = 24000000;
607		hpll = hpll_rates[0][rate];
608	}
609	hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, clkin);
610	pr_debug("clkin @%u MHz\n", clkin / 1000000);
611
612	/*
613	 * High-speed PLL clock derived from the crystal. This the CPU clock,
614	 * and we assume that it is enabled. It can be configured through the
615	 * HPLL_PARAM register, or set to a specified frequency by strapping.
616	 */
617	regmap_read(map, ASPEED_HPLL_PARAM, &val);
618	if (val & AST2400_HPLL_PROGRAMMED)
619		hw = aspeed_ast2400_calc_pll("hpll", val);
620	else
621		hw = clk_hw_register_fixed_rate(NULL, "hpll", "clkin", 0,
622				hpll * 1000000);
623
624	aspeed_clk_data->hws[ASPEED_CLK_HPLL] = hw;
625
626	/*
627	 * Strap bits 11:10 define the CPU/AHB clock frequency ratio (aka HCLK)
628	 *   00: Select CPU:AHB = 1:1
629	 *   01: Select CPU:AHB = 2:1
630	 *   10: Select CPU:AHB = 4:1
631	 *   11: Select CPU:AHB = 3:1
632	 */
633	regmap_read(map, ASPEED_STRAP, &val);
634	val = (val >> 10) & 0x3;
635	div = val + 1;
636	if (div == 3)
637		div = 4;
638	else if (div == 4)
639		div = 3;
640	hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
641	aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
642
643	/* APB clock clock selection register SCU08 (aka PCLK) */
644	hw = clk_hw_register_divider_table(NULL, "apb", "hpll", 0,
645			scu_base + ASPEED_CLK_SELECTION, 23, 3, 0,
646			ast2400_div_table,
647			&aspeed_clk_lock);
648	aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
649}
650
651static void __init aspeed_ast2500_cc(struct regmap *map)
652{
653	struct clk_hw *hw;
654	u32 val, freq, div;
655
656	/* CLKIN is the crystal oscillator, 24 or 25MHz selected by strapping */
657	regmap_read(map, ASPEED_STRAP, &val);
658	if (val & CLKIN_25MHZ_EN)
659		freq = 25000000;
660	else
661		freq = 24000000;
662	hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, freq);
663	pr_debug("clkin @%u MHz\n", freq / 1000000);
664
665	/*
666	 * High-speed PLL clock derived from the crystal. This the CPU clock,
667	 * and we assume that it is enabled
668	 */
669	regmap_read(map, ASPEED_HPLL_PARAM, &val);
670	aspeed_clk_data->hws[ASPEED_CLK_HPLL] = aspeed_ast2500_calc_pll("hpll", val);
671
672	/* Strap bits 11:9 define the AXI/AHB clock frequency ratio (aka HCLK)*/
673	regmap_read(map, ASPEED_STRAP, &val);
674	val = (val >> 9) & 0x7;
675	WARN(val == 0, "strapping is zero: cannot determine ahb clock");
676	div = 2 * (val + 1);
677	hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
678	aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
679
680	/* APB clock clock selection register SCU08 (aka PCLK) */
681	regmap_read(map, ASPEED_CLK_SELECTION, &val);
682	val = (val >> 23) & 0x7;
683	div = 4 * (val + 1);
684	hw = clk_hw_register_fixed_factor(NULL, "apb", "hpll", 0, 1, div);
685	aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
686};
687
688static void __init aspeed_cc_init(struct device_node *np)
689{
690	struct regmap *map;
691	u32 val;
692	int ret;
693	int i;
694
695	scu_base = of_iomap(np, 0);
696	if (!scu_base)
697		return;
698
699	aspeed_clk_data = kzalloc(struct_size(aspeed_clk_data, hws,
700					      ASPEED_NUM_CLKS),
701				  GFP_KERNEL);
702	if (!aspeed_clk_data)
703		return;
704	aspeed_clk_data->num = ASPEED_NUM_CLKS;
705
706	/*
707	 * This way all clocks fetched before the platform device probes,
708	 * except those we assign here for early use, will be deferred.
709	 */
710	for (i = 0; i < ASPEED_NUM_CLKS; i++)
711		aspeed_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);
712
713	map = syscon_node_to_regmap(np);
714	if (IS_ERR(map)) {
715		pr_err("no syscon regmap\n");
716		return;
717	}
718	/*
719	 * We check that the regmap works on this very first access,
720	 * but as this is an MMIO-backed regmap, subsequent regmap
721	 * access is not going to fail and we skip error checks from
722	 * this point.
723	 */
724	ret = regmap_read(map, ASPEED_STRAP, &val);
725	if (ret) {
726		pr_err("failed to read strapping register\n");
727		return;
728	}
729
730	if (of_device_is_compatible(np, "aspeed,ast2400-scu"))
731		aspeed_ast2400_cc(map);
732	else if (of_device_is_compatible(np, "aspeed,ast2500-scu"))
733		aspeed_ast2500_cc(map);
734	else
735		pr_err("unknown platform, failed to add clocks\n");
736	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, aspeed_clk_data);
737	if (ret)
738		pr_err("failed to add DT provider: %d\n", ret);
739};
740CLK_OF_DECLARE_DRIVER(aspeed_cc_g5, "aspeed,ast2500-scu", aspeed_cc_init);
741CLK_OF_DECLARE_DRIVER(aspeed_cc_g4, "aspeed,ast2400-scu", aspeed_cc_init);
742