1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2019
4  * Lukasz Majewski, DENX Software Engineering, lukma@denx.de
5  *
6  * Common Clock Framework [CCF] driver for Sandbox
7  */
8 
9 #include <common.h>
10 #include <dm.h>
11 #include <clk.h>
12 #include <malloc.h>
13 #include <asm/clk.h>
14 #include <clk-uclass.h>
15 #include <dm/devres.h>
16 #include <linux/bitops.h>
17 #include <linux/clk-provider.h>
18 #include <sandbox-clk.h>
19 #include <linux/err.h>
20 
21 /*
22  * Sandbox implementation of CCF primitives necessary for clk-uclass testing
23  *
24  * --- Sandbox PLLv3 ---
25  */
26 struct clk_pllv3 {
27 	struct clk	clk;
28 	u32		div_mask;
29 	u32		div_shift;
30 };
31 
sandbox_clk_enable_count(struct clk * clk)32 int sandbox_clk_enable_count(struct clk *clk)
33 {
34 	struct clk *clkp = NULL;
35 	int ret;
36 
37 	ret = clk_get_by_id(clk->id, &clkp);
38 	if (ret)
39 		return 0;
40 
41 	return clkp->enable_count;
42 }
43 
clk_pllv3_get_rate(struct clk * clk)44 static ulong clk_pllv3_get_rate(struct clk *clk)
45 {
46 	unsigned long parent_rate = clk_get_parent_rate(clk);
47 
48 	return parent_rate * 24;
49 }
50 
51 static const struct clk_ops clk_pllv3_generic_ops = {
52 	.get_rate       = clk_pllv3_get_rate,
53 };
54 
sandbox_clk_pllv3(enum sandbox_pllv3_type type,const char * name,const char * parent_name,void __iomem * base,u32 div_mask)55 struct clk *sandbox_clk_pllv3(enum sandbox_pllv3_type type, const char *name,
56 			      const char *parent_name, void __iomem *base,
57 			      u32 div_mask)
58 {
59 	struct clk_pllv3 *pll;
60 	struct clk *clk;
61 	char *drv_name = "sandbox_clk_pllv3";
62 	int ret;
63 
64 	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
65 	if (!pll)
66 		return ERR_PTR(-ENOMEM);
67 
68 	pll->div_mask = div_mask;
69 	clk = &pll->clk;
70 
71 	ret = clk_register(clk, drv_name, name, parent_name);
72 	if (ret) {
73 		kfree(pll);
74 		return ERR_PTR(ret);
75 	}
76 
77 	return clk;
78 }
79 
80 U_BOOT_DRIVER(sandbox_clk_pll_generic) = {
81 	.name	= "sandbox_clk_pllv3",
82 	.id	= UCLASS_CLK,
83 	.ops	= &clk_pllv3_generic_ops,
84 };
85 
86 /* --- Sandbox PLLv3 --- */
87 /* --- Sandbox Gate  --- */
88 struct clk_gate2 {
89 	struct clk clk;
90 	bool	state;
91 };
92 
93 #define to_clk_gate2(_clk) container_of(_clk, struct clk_gate2, clk)
94 
clk_gate2_enable(struct clk * clk)95 static int clk_gate2_enable(struct clk *clk)
96 {
97 	struct clk_gate2 *gate = to_clk_gate2(dev_get_clk_ptr(clk->dev));
98 
99 	gate->state = 1;
100 	return 0;
101 }
102 
clk_gate2_disable(struct clk * clk)103 static int clk_gate2_disable(struct clk *clk)
104 {
105 	struct clk_gate2 *gate = to_clk_gate2(dev_get_clk_ptr(clk->dev));
106 
107 	gate->state = 0;
108 	return 0;
109 }
110 
111 static const struct clk_ops clk_gate2_ops = {
112 	.enable = clk_gate2_enable,
113 	.disable = clk_gate2_disable,
114 	.get_rate = clk_generic_get_rate,
115 };
116 
sandbox_clk_register_gate2(struct device * dev,const char * name,const char * parent_name,unsigned long flags,void __iomem * reg,u8 bit_idx,u8 cgr_val,u8 clk_gate2_flags)117 struct clk *sandbox_clk_register_gate2(struct device *dev, const char *name,
118 				       const char *parent_name,
119 				       unsigned long flags, void __iomem *reg,
120 				       u8 bit_idx, u8 cgr_val,
121 				       u8 clk_gate2_flags)
122 {
123 	struct clk_gate2 *gate;
124 	struct clk *clk;
125 	int ret;
126 
127 	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
128 	if (!gate)
129 		return ERR_PTR(-ENOMEM);
130 
131 	gate->state = 0;
132 	clk = &gate->clk;
133 	clk->flags = flags;
134 
135 	ret = clk_register(clk, "sandbox_clk_gate2", name, parent_name);
136 	if (ret) {
137 		kfree(gate);
138 		return ERR_PTR(ret);
139 	}
140 
141 	return clk;
142 }
143 
144 U_BOOT_DRIVER(sandbox_clk_gate2) = {
145 	.name	= "sandbox_clk_gate2",
146 	.id	= UCLASS_CLK,
147 	.ops	= &clk_gate2_ops,
148 };
149 
sandbox_clk_composite_divider_recalc_rate(struct clk * clk)150 static unsigned long sandbox_clk_composite_divider_recalc_rate(struct clk *clk)
151 {
152 	struct clk_divider *divider = (struct clk_divider *)to_clk_divider(clk);
153 	struct clk_composite *composite = (struct clk_composite *)clk->data;
154 	ulong parent_rate = clk_get_parent_rate(&composite->clk);
155 	unsigned int val;
156 
157 	val = divider->io_divider_val;
158 	val >>= divider->shift;
159 	val &= clk_div_mask(divider->width);
160 
161 	return divider_recalc_rate(clk, parent_rate, val, divider->table,
162 				   divider->flags, divider->width);
163 }
164 
165 static const struct clk_ops sandbox_clk_composite_divider_ops = {
166 	.get_rate = sandbox_clk_composite_divider_recalc_rate,
167 };
168 
sandbox_clk_composite(const char * name,const char * const * parent_names,int num_parents,void __iomem * reg,unsigned long flags)169 struct clk *sandbox_clk_composite(const char *name,
170 				  const char * const *parent_names,
171 				  int num_parents, void __iomem *reg,
172 				  unsigned long flags)
173 {
174 	struct clk *clk = ERR_PTR(-ENOMEM);
175 	struct clk_divider *div = NULL;
176 	struct clk_gate *gate = NULL;
177 	struct clk_mux *mux = NULL;
178 
179 	mux = kzalloc(sizeof(*mux), GFP_KERNEL);
180 	if (!mux)
181 		goto fail;
182 
183 	mux->reg = reg;
184 	mux->shift = 24;
185 	mux->mask = 0x7;
186 	mux->num_parents = num_parents;
187 	mux->flags = flags;
188 	mux->parent_names = parent_names;
189 
190 	div = kzalloc(sizeof(*div), GFP_KERNEL);
191 	if (!div)
192 		goto fail;
193 
194 	div->reg = reg;
195 	div->shift = 16;
196 	div->width = 3;
197 	div->flags = CLK_DIVIDER_ROUND_CLOSEST | flags;
198 
199 	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
200 	if (!gate)
201 		goto fail;
202 
203 	gate->reg = reg;
204 	gate->bit_idx = 28;
205 	gate->flags = flags;
206 
207 	clk = clk_register_composite(NULL, name,
208 				     parent_names, num_parents,
209 				     &mux->clk, &clk_mux_ops, &div->clk,
210 				     &sandbox_clk_composite_divider_ops,
211 				     &gate->clk, &clk_gate_ops, flags);
212 	if (IS_ERR(clk))
213 		goto fail;
214 
215 	return clk;
216 
217 fail:
218 	kfree(gate);
219 	kfree(div);
220 	kfree(mux);
221 	return ERR_CAST(clk);
222 }
223 
224 /* --- Sandbox Gate --- */
225 /* The CCF core driver itself */
226 static const struct udevice_id sandbox_clk_ccf_test_ids[] = {
227 	{ .compatible = "sandbox,clk-ccf" },
228 	{ }
229 };
230 
231 static const char *const usdhc_sels[] = { "pll3_60m", "pll3_80m", };
232 static const char *const i2c_sels[] = { "pll3_60m", "pll3_80m", };
233 
sandbox_clk_ccf_probe(struct udevice * dev)234 static int sandbox_clk_ccf_probe(struct udevice *dev)
235 {
236 	void *base = NULL;
237 	u32 reg;
238 
239 	clk_dm(SANDBOX_CLK_PLL3,
240 	       sandbox_clk_pllv3(SANDBOX_PLLV3_USB, "pll3_usb_otg", "osc",
241 				 base + 0x10, 0x3));
242 
243 	clk_dm(SANDBOX_CLK_PLL3_60M,
244 	       sandbox_clk_fixed_factor("pll3_60m",  "pll3_usb_otg",   1, 8));
245 
246 	clk_dm(SANDBOX_CLK_PLL3_80M,
247 	       sandbox_clk_fixed_factor("pll3_80m",  "pll3_usb_otg",   1, 6));
248 
249 	/* The HW adds +1 to the divider value (2+1) is the divider */
250 	reg = (2 << 19);
251 	clk_dm(SANDBOX_CLK_ECSPI_ROOT,
252 	       sandbox_clk_divider("ecspi_root", "pll3_60m", &reg, 19, 6));
253 
254 	reg = 0;
255 	clk_dm(SANDBOX_CLK_ECSPI0,
256 	       sandbox_clk_gate("ecspi0", "ecspi_root", &reg, 0, 0));
257 
258 	clk_dm(SANDBOX_CLK_ECSPI1,
259 	       sandbox_clk_gate2("ecspi1", "ecspi_root", base + 0x6c, 0));
260 
261 	/* Select 'pll3_60m' */
262 	reg = 0;
263 	clk_dm(SANDBOX_CLK_USDHC1_SEL,
264 	       sandbox_clk_mux("usdhc1_sel", &reg, 16, 1, usdhc_sels,
265 			       ARRAY_SIZE(usdhc_sels)));
266 
267 	/* Select 'pll3_80m' */
268 	reg = BIT(17);
269 	clk_dm(SANDBOX_CLK_USDHC2_SEL,
270 	       sandbox_clk_mux("usdhc2_sel", &reg, 17, 1, usdhc_sels,
271 			       ARRAY_SIZE(usdhc_sels)));
272 
273 	reg = BIT(28) | BIT(24) | BIT(16);
274 	clk_dm(SANDBOX_CLK_I2C,
275 	       sandbox_clk_composite("i2c", i2c_sels, ARRAY_SIZE(i2c_sels),
276 				     &reg, CLK_SET_RATE_UNGATE));
277 
278 	clk_dm(SANDBOX_CLK_I2C_ROOT,
279 	       sandbox_clk_gate2("i2c_root", "i2c", base + 0x7c, 0));
280 
281 	return 0;
282 }
283 
284 U_BOOT_DRIVER(sandbox_clk_ccf) = {
285 	.name = "sandbox_clk_ccf",
286 	.id = UCLASS_CLK,
287 	.probe = sandbox_clk_ccf_probe,
288 	.of_match = sandbox_clk_ccf_test_ids,
289 };
290