1 /*
2  * Marvell Armada CP110 System Controller
3  *
4  * Copyright (C) 2016 Marvell
5  *
6  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
7  *
8  * This file is licensed under the terms of the GNU General Public
9  * License version 2.  This program is licensed "as is" without any
10  * warranty of any kind, whether express or implied.
11  */
12 
13 /*
14  * CP110 has 6 core clocks:
15  *
16  *  - PLL0		(1 Ghz)
17  *    - PPv2 core	(1/3 PLL0)
18  *    - x2 Core		(1/2 PLL0)
19  *	- Core		(1/2 x2 Core)
20  *    - SDIO		(2/5 PLL0)
21  *
22  *  - NAND clock, which is either:
23  *    - Equal to SDIO clock
24  *    - 2/5 PLL0
25  *
26  * CP110 has 32 gatable clocks, for the various peripherals in the IP.
27  */
28 
29 #define pr_fmt(fmt) "cp110-system-controller: " fmt
30 
31 #include <linux/clk-provider.h>
32 #include <linux/mfd/syscon.h>
33 #include <linux/init.h>
34 #include <linux/of.h>
35 #include <linux/of_address.h>
36 #include <linux/platform_device.h>
37 #include <linux/regmap.h>
38 #include <linux/slab.h>
39 
40 #define CP110_PM_CLOCK_GATING_REG	0x220
41 #define CP110_NAND_FLASH_CLK_CTRL_REG	0x700
42 #define    NF_CLOCK_SEL_400_MASK	BIT(0)
43 
44 enum {
45 	CP110_CLK_TYPE_CORE,
46 	CP110_CLK_TYPE_GATABLE,
47 };
48 
49 #define CP110_MAX_CORE_CLOCKS		6
50 #define CP110_MAX_GATABLE_CLOCKS	32
51 
52 #define CP110_CLK_NUM \
53 	(CP110_MAX_CORE_CLOCKS + CP110_MAX_GATABLE_CLOCKS)
54 
55 #define CP110_CORE_PLL0			0
56 #define CP110_CORE_PPV2			1
57 #define CP110_CORE_X2CORE		2
58 #define CP110_CORE_CORE			3
59 #define CP110_CORE_NAND			4
60 #define CP110_CORE_SDIO			5
61 
62 /* A number of gatable clocks need special handling */
63 #define CP110_GATE_AUDIO		0
64 #define CP110_GATE_COMM_UNIT		1
65 #define CP110_GATE_NAND			2
66 #define CP110_GATE_PPV2			3
67 #define CP110_GATE_SDIO			4
68 #define CP110_GATE_MG			5
69 #define CP110_GATE_MG_CORE		6
70 #define CP110_GATE_XOR1			7
71 #define CP110_GATE_XOR0			8
72 #define CP110_GATE_GOP_DP		9
73 #define CP110_GATE_PCIE_X1_0		11
74 #define CP110_GATE_PCIE_X1_1		12
75 #define CP110_GATE_PCIE_X4		13
76 #define CP110_GATE_PCIE_XOR		14
77 #define CP110_GATE_SATA			15
78 #define CP110_GATE_SATA_USB		16
79 #define CP110_GATE_MAIN			17
80 #define CP110_GATE_SDMMC_GOP		18
81 #define CP110_GATE_SLOW_IO		21
82 #define CP110_GATE_USB3H0		22
83 #define CP110_GATE_USB3H1		23
84 #define CP110_GATE_USB3DEV		24
85 #define CP110_GATE_EIP150		25
86 #define CP110_GATE_EIP197		26
87 
88 static const char * const gate_base_names[] = {
89 	[CP110_GATE_AUDIO]	= "audio",
90 	[CP110_GATE_COMM_UNIT]	= "communit",
91 	[CP110_GATE_NAND]	= "nand",
92 	[CP110_GATE_PPV2]	= "ppv2",
93 	[CP110_GATE_SDIO]	= "sdio",
94 	[CP110_GATE_MG]		= "mg-domain",
95 	[CP110_GATE_MG_CORE]	= "mg-core",
96 	[CP110_GATE_XOR1]	= "xor1",
97 	[CP110_GATE_XOR0]	= "xor0",
98 	[CP110_GATE_GOP_DP]	= "gop-dp",
99 	[CP110_GATE_PCIE_X1_0]	= "pcie_x10",
100 	[CP110_GATE_PCIE_X1_1]	= "pcie_x11",
101 	[CP110_GATE_PCIE_X4]	= "pcie_x4",
102 	[CP110_GATE_PCIE_XOR]	= "pcie-xor",
103 	[CP110_GATE_SATA]	= "sata",
104 	[CP110_GATE_SATA_USB]	= "sata-usb",
105 	[CP110_GATE_MAIN]	= "main",
106 	[CP110_GATE_SDMMC_GOP]	= "sd-mmc-gop",
107 	[CP110_GATE_SLOW_IO]	= "slow-io",
108 	[CP110_GATE_USB3H0]	= "usb3h0",
109 	[CP110_GATE_USB3H1]	= "usb3h1",
110 	[CP110_GATE_USB3DEV]	= "usb3dev",
111 	[CP110_GATE_EIP150]	= "eip150",
112 	[CP110_GATE_EIP197]	= "eip197"
113 };
114 
115 struct cp110_gate_clk {
116 	struct clk_hw hw;
117 	struct regmap *regmap;
118 	u8 bit_idx;
119 };
120 
121 #define to_cp110_gate_clk(hw) container_of(hw, struct cp110_gate_clk, hw)
122 
123 static int cp110_gate_enable(struct clk_hw *hw)
124 {
125 	struct cp110_gate_clk *gate = to_cp110_gate_clk(hw);
126 
127 	regmap_update_bits(gate->regmap, CP110_PM_CLOCK_GATING_REG,
128 			   BIT(gate->bit_idx), BIT(gate->bit_idx));
129 
130 	return 0;
131 }
132 
133 static void cp110_gate_disable(struct clk_hw *hw)
134 {
135 	struct cp110_gate_clk *gate = to_cp110_gate_clk(hw);
136 
137 	regmap_update_bits(gate->regmap, CP110_PM_CLOCK_GATING_REG,
138 			   BIT(gate->bit_idx), 0);
139 }
140 
141 static int cp110_gate_is_enabled(struct clk_hw *hw)
142 {
143 	struct cp110_gate_clk *gate = to_cp110_gate_clk(hw);
144 	u32 val;
145 
146 	regmap_read(gate->regmap, CP110_PM_CLOCK_GATING_REG, &val);
147 
148 	return val & BIT(gate->bit_idx);
149 }
150 
151 static const struct clk_ops cp110_gate_ops = {
152 	.enable = cp110_gate_enable,
153 	.disable = cp110_gate_disable,
154 	.is_enabled = cp110_gate_is_enabled,
155 };
156 
157 static struct clk_hw *cp110_register_gate(const char *name,
158 					  const char *parent_name,
159 					  struct regmap *regmap, u8 bit_idx)
160 {
161 	struct cp110_gate_clk *gate;
162 	struct clk_hw *hw;
163 	struct clk_init_data init;
164 	int ret;
165 
166 	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
167 	if (!gate)
168 		return ERR_PTR(-ENOMEM);
169 
170 	memset(&init, 0, sizeof(init));
171 
172 	init.name = name;
173 	init.ops = &cp110_gate_ops;
174 	init.parent_names = &parent_name;
175 	init.num_parents = 1;
176 
177 	gate->regmap = regmap;
178 	gate->bit_idx = bit_idx;
179 	gate->hw.init = &init;
180 
181 	hw = &gate->hw;
182 	ret = clk_hw_register(NULL, hw);
183 	if (ret) {
184 		kfree(gate);
185 		hw = ERR_PTR(ret);
186 	}
187 
188 	return hw;
189 }
190 
191 static void cp110_unregister_gate(struct clk_hw *hw)
192 {
193 	clk_hw_unregister(hw);
194 	kfree(to_cp110_gate_clk(hw));
195 }
196 
197 static struct clk_hw *cp110_of_clk_get(struct of_phandle_args *clkspec,
198 				       void *data)
199 {
200 	struct clk_hw_onecell_data *clk_data = data;
201 	unsigned int type = clkspec->args[0];
202 	unsigned int idx = clkspec->args[1];
203 
204 	if (type == CP110_CLK_TYPE_CORE) {
205 		if (idx > CP110_MAX_CORE_CLOCKS)
206 			return ERR_PTR(-EINVAL);
207 		return clk_data->hws[idx];
208 	} else if (type == CP110_CLK_TYPE_GATABLE) {
209 		if (idx > CP110_MAX_GATABLE_CLOCKS)
210 			return ERR_PTR(-EINVAL);
211 		return clk_data->hws[CP110_MAX_CORE_CLOCKS + idx];
212 	}
213 
214 	return ERR_PTR(-EINVAL);
215 }
216 
217 static char *cp110_unique_name(struct device *dev, struct device_node *np,
218 			       const char *name)
219 {
220 	const __be32 *reg;
221 	u64 addr;
222 
223 	/* Do not create a name if there is no clock */
224 	if (!name)
225 		return NULL;
226 
227 	reg = of_get_property(np, "reg", NULL);
228 	addr = of_translate_address(np, reg);
229 	return devm_kasprintf(dev, GFP_KERNEL, "%llx-%s",
230 			      (unsigned long long)addr, name);
231 }
232 
233 static int cp110_syscon_common_probe(struct platform_device *pdev,
234 				     struct device_node *syscon_node)
235 {
236 	struct regmap *regmap;
237 	struct device *dev = &pdev->dev;
238 	struct device_node *np = dev->of_node;
239 	const char *ppv2_name, *pll0_name, *core_name, *x2core_name, *nand_name,
240 		*sdio_name;
241 	struct clk_hw_onecell_data *cp110_clk_data;
242 	struct clk_hw *hw, **cp110_clks;
243 	u32 nand_clk_ctrl;
244 	int i, ret;
245 	char *gate_name[ARRAY_SIZE(gate_base_names)];
246 
247 	regmap = syscon_node_to_regmap(syscon_node);
248 	if (IS_ERR(regmap))
249 		return PTR_ERR(regmap);
250 
251 	ret = regmap_read(regmap, CP110_NAND_FLASH_CLK_CTRL_REG,
252 			  &nand_clk_ctrl);
253 	if (ret)
254 		return ret;
255 
256 	cp110_clk_data = devm_kzalloc(dev, sizeof(*cp110_clk_data) +
257 				      sizeof(struct clk_hw *) * CP110_CLK_NUM,
258 				      GFP_KERNEL);
259 	if (!cp110_clk_data)
260 		return -ENOMEM;
261 
262 	cp110_clks = cp110_clk_data->hws;
263 	cp110_clk_data->num = CP110_CLK_NUM;
264 
265 	/* Register the PLL0 which is the root of the hw tree */
266 	pll0_name = cp110_unique_name(dev, syscon_node, "pll0");
267 	hw = clk_hw_register_fixed_rate(NULL, pll0_name, NULL, 0,
268 					1000 * 1000 * 1000);
269 	if (IS_ERR(hw)) {
270 		ret = PTR_ERR(hw);
271 		goto fail_pll0;
272 	}
273 
274 	cp110_clks[CP110_CORE_PLL0] = hw;
275 
276 	/* PPv2 is PLL0/3 */
277 	ppv2_name = cp110_unique_name(dev, syscon_node, "ppv2-core");
278 	hw = clk_hw_register_fixed_factor(NULL, ppv2_name, pll0_name, 0, 1, 3);
279 	if (IS_ERR(hw)) {
280 		ret = PTR_ERR(hw);
281 		goto fail_ppv2;
282 	}
283 
284 	cp110_clks[CP110_CORE_PPV2] = hw;
285 
286 	/* X2CORE clock is PLL0/2 */
287 	x2core_name = cp110_unique_name(dev, syscon_node, "x2core");
288 	hw = clk_hw_register_fixed_factor(NULL, x2core_name, pll0_name,
289 					  0, 1, 2);
290 	if (IS_ERR(hw)) {
291 		ret = PTR_ERR(hw);
292 		goto fail_eip;
293 	}
294 
295 	cp110_clks[CP110_CORE_X2CORE] = hw;
296 
297 	/* Core clock is X2CORE/2 */
298 	core_name = cp110_unique_name(dev, syscon_node, "core");
299 	hw = clk_hw_register_fixed_factor(NULL, core_name, x2core_name,
300 					  0, 1, 2);
301 	if (IS_ERR(hw)) {
302 		ret = PTR_ERR(hw);
303 		goto fail_core;
304 	}
305 
306 	cp110_clks[CP110_CORE_CORE] = hw;
307 	/* NAND can be either PLL0/2.5 or core clock */
308 	nand_name = cp110_unique_name(dev, syscon_node, "nand-core");
309 	if (nand_clk_ctrl & NF_CLOCK_SEL_400_MASK)
310 		hw = clk_hw_register_fixed_factor(NULL, nand_name,
311 						   pll0_name, 0, 2, 5);
312 	else
313 		hw = clk_hw_register_fixed_factor(NULL, nand_name,
314 						   core_name, 0, 1, 1);
315 	if (IS_ERR(hw)) {
316 		ret = PTR_ERR(hw);
317 		goto fail_nand;
318 	}
319 
320 	cp110_clks[CP110_CORE_NAND] = hw;
321 
322 	/* SDIO clock is PLL0/2.5 */
323 	sdio_name = cp110_unique_name(dev, syscon_node, "sdio-core");
324 	hw = clk_hw_register_fixed_factor(NULL, sdio_name,
325 					  pll0_name, 0, 2, 5);
326 	if (IS_ERR(hw)) {
327 		ret = PTR_ERR(hw);
328 		goto fail_sdio;
329 	}
330 
331 	cp110_clks[CP110_CORE_SDIO] = hw;
332 
333 	/* create the unique name for all the gate clocks */
334 	for (i = 0; i < ARRAY_SIZE(gate_base_names); i++)
335 		gate_name[i] =	cp110_unique_name(dev, syscon_node,
336 						  gate_base_names[i]);
337 
338 	for (i = 0; i < ARRAY_SIZE(gate_base_names); i++) {
339 		const char *parent;
340 
341 		if (gate_name[i] == NULL)
342 			continue;
343 
344 		switch (i) {
345 		case CP110_GATE_NAND:
346 			parent = nand_name;
347 			break;
348 		case CP110_GATE_MG:
349 		case CP110_GATE_GOP_DP:
350 		case CP110_GATE_PPV2:
351 			parent = ppv2_name;
352 			break;
353 		case CP110_GATE_SDIO:
354 			parent = sdio_name;
355 			break;
356 		case CP110_GATE_MAIN:
357 		case CP110_GATE_PCIE_XOR:
358 		case CP110_GATE_PCIE_X4:
359 		case CP110_GATE_EIP150:
360 		case CP110_GATE_EIP197:
361 			parent = x2core_name;
362 			break;
363 		default:
364 			parent = core_name;
365 			break;
366 		}
367 		hw = cp110_register_gate(gate_name[i], parent, regmap, i);
368 
369 		if (IS_ERR(hw)) {
370 			ret = PTR_ERR(hw);
371 			goto fail_gate;
372 		}
373 
374 		cp110_clks[CP110_MAX_CORE_CLOCKS + i] = hw;
375 	}
376 
377 	ret = of_clk_add_hw_provider(np, cp110_of_clk_get, cp110_clk_data);
378 	if (ret)
379 		goto fail_clk_add;
380 
381 	platform_set_drvdata(pdev, cp110_clks);
382 
383 	return 0;
384 
385 fail_clk_add:
386 fail_gate:
387 	for (i = 0; i < CP110_MAX_GATABLE_CLOCKS; i++) {
388 		hw = cp110_clks[CP110_MAX_CORE_CLOCKS + i];
389 
390 		if (hw)
391 			cp110_unregister_gate(hw);
392 	}
393 
394 	clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_SDIO]);
395 fail_sdio:
396 	clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_NAND]);
397 fail_nand:
398 	clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_CORE]);
399 fail_core:
400 	clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_X2CORE]);
401 fail_eip:
402 	clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_PPV2]);
403 fail_ppv2:
404 	clk_hw_unregister_fixed_rate(cp110_clks[CP110_CORE_PLL0]);
405 fail_pll0:
406 	return ret;
407 }
408 
409 static int cp110_syscon_legacy_clk_probe(struct platform_device *pdev)
410 {
411 	dev_warn(&pdev->dev, FW_WARN "Using legacy device tree binding\n");
412 	dev_warn(&pdev->dev, FW_WARN "Update your device tree:\n");
413 	dev_warn(&pdev->dev, FW_WARN
414 		 "This binding won't be supported in future kernels\n");
415 
416 	return cp110_syscon_common_probe(pdev, pdev->dev.of_node);
417 }
418 
419 static int cp110_clk_probe(struct platform_device *pdev)
420 {
421 	return cp110_syscon_common_probe(pdev, pdev->dev.of_node->parent);
422 }
423 
424 static const struct of_device_id cp110_syscon_legacy_of_match[] = {
425 	{ .compatible = "marvell,cp110-system-controller0", },
426 	{ }
427 };
428 
429 static struct platform_driver cp110_syscon_legacy_driver = {
430 	.probe = cp110_syscon_legacy_clk_probe,
431 	.driver		= {
432 		.name	= "marvell-cp110-system-controller0",
433 		.of_match_table = cp110_syscon_legacy_of_match,
434 		.suppress_bind_attrs = true,
435 	},
436 };
437 builtin_platform_driver(cp110_syscon_legacy_driver);
438 
439 static const struct of_device_id cp110_clock_of_match[] = {
440 	{ .compatible = "marvell,cp110-clock", },
441 	{ }
442 };
443 
444 static struct platform_driver cp110_clock_driver = {
445 	.probe = cp110_clk_probe,
446 	.driver		= {
447 		.name	= "marvell-cp110-clock",
448 		.of_match_table = cp110_clock_of_match,
449 		.suppress_bind_attrs = true,
450 	},
451 };
452 builtin_platform_driver(cp110_clock_driver);
453