xref: /openbmc/linux/drivers/clk/ingenic/jz4740-cgu.c (revision 7587eb18)
1 /*
2  * Ingenic JZ4740 SoC CGU driver
3  *
4  * Copyright (c) 2015 Imagination Technologies
5  * Author: Paul Burton <paul.burton@imgtec.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation; either version 2 of
10  * the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 #include <linux/clk-provider.h>
19 #include <linux/delay.h>
20 #include <linux/of.h>
21 #include <dt-bindings/clock/jz4740-cgu.h>
22 #include <asm/mach-jz4740/clock.h>
23 #include "cgu.h"
24 
25 /* CGU register offsets */
26 #define CGU_REG_CPCCR		0x00
27 #define CGU_REG_LCR		0x04
28 #define CGU_REG_CPPCR		0x10
29 #define CGU_REG_CLKGR		0x20
30 #define CGU_REG_SCR		0x24
31 #define CGU_REG_I2SCDR		0x60
32 #define CGU_REG_LPCDR		0x64
33 #define CGU_REG_MSCCDR		0x68
34 #define CGU_REG_UHCCDR		0x6c
35 #define CGU_REG_SSICDR		0x74
36 
37 /* bits within a PLL control register */
38 #define PLLCTL_M_SHIFT		23
39 #define PLLCTL_M_MASK		(0x1ff << PLLCTL_M_SHIFT)
40 #define PLLCTL_N_SHIFT		18
41 #define PLLCTL_N_MASK		(0x1f << PLLCTL_N_SHIFT)
42 #define PLLCTL_OD_SHIFT		16
43 #define PLLCTL_OD_MASK		(0x3 << PLLCTL_OD_SHIFT)
44 #define PLLCTL_STABLE		(1 << 10)
45 #define PLLCTL_BYPASS		(1 << 9)
46 #define PLLCTL_ENABLE		(1 << 8)
47 
48 /* bits within the LCR register */
49 #define LCR_SLEEP		(1 << 0)
50 
51 /* bits within the CLKGR register */
52 #define CLKGR_UDC		(1 << 11)
53 
54 static struct ingenic_cgu *cgu;
55 
56 static const s8 pll_od_encoding[4] = {
57 	0x0, 0x1, -1, 0x3,
58 };
59 
60 static const struct ingenic_cgu_clk_info jz4740_cgu_clocks[] = {
61 
62 	/* External clocks */
63 
64 	[JZ4740_CLK_EXT] = { "ext", CGU_CLK_EXT },
65 	[JZ4740_CLK_RTC] = { "rtc", CGU_CLK_EXT },
66 
67 	[JZ4740_CLK_PLL] = {
68 		"pll", CGU_CLK_PLL,
69 		.parents = { JZ4740_CLK_EXT, -1, -1, -1 },
70 		.pll = {
71 			.reg = CGU_REG_CPPCR,
72 			.m_shift = 23,
73 			.m_bits = 9,
74 			.m_offset = 2,
75 			.n_shift = 18,
76 			.n_bits = 5,
77 			.n_offset = 2,
78 			.od_shift = 16,
79 			.od_bits = 2,
80 			.od_max = 4,
81 			.od_encoding = pll_od_encoding,
82 			.stable_bit = 10,
83 			.bypass_bit = 9,
84 			.enable_bit = 8,
85 		},
86 	},
87 
88 	/* Muxes & dividers */
89 
90 	[JZ4740_CLK_PLL_HALF] = {
91 		"pll half", CGU_CLK_DIV,
92 		.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
93 		.div = { CGU_REG_CPCCR, 21, 1, 1, -1, -1, -1 },
94 	},
95 
96 	[JZ4740_CLK_CCLK] = {
97 		"cclk", CGU_CLK_DIV,
98 		.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
99 		.div = { CGU_REG_CPCCR, 0, 1, 4, 22, -1, -1 },
100 	},
101 
102 	[JZ4740_CLK_HCLK] = {
103 		"hclk", CGU_CLK_DIV,
104 		.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
105 		.div = { CGU_REG_CPCCR, 4, 1, 4, 22, -1, -1 },
106 	},
107 
108 	[JZ4740_CLK_PCLK] = {
109 		"pclk", CGU_CLK_DIV,
110 		.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
111 		.div = { CGU_REG_CPCCR, 8, 1, 4, 22, -1, -1 },
112 	},
113 
114 	[JZ4740_CLK_MCLK] = {
115 		"mclk", CGU_CLK_DIV,
116 		.parents = { JZ4740_CLK_PLL, -1, -1, -1 },
117 		.div = { CGU_REG_CPCCR, 12, 1, 4, 22, -1, -1 },
118 	},
119 
120 	[JZ4740_CLK_LCD] = {
121 		"lcd", CGU_CLK_DIV | CGU_CLK_GATE,
122 		.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
123 		.div = { CGU_REG_CPCCR, 16, 1, 5, 22, -1, -1 },
124 		.gate = { CGU_REG_CLKGR, 10 },
125 	},
126 
127 	[JZ4740_CLK_LCD_PCLK] = {
128 		"lcd_pclk", CGU_CLK_DIV,
129 		.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
130 		.div = { CGU_REG_LPCDR, 0, 1, 11, -1, -1, -1 },
131 	},
132 
133 	[JZ4740_CLK_I2S] = {
134 		"i2s", CGU_CLK_MUX | CGU_CLK_DIV | CGU_CLK_GATE,
135 		.parents = { JZ4740_CLK_EXT, JZ4740_CLK_PLL_HALF, -1, -1 },
136 		.mux = { CGU_REG_CPCCR, 31, 1 },
137 		.div = { CGU_REG_I2SCDR, 0, 1, 8, -1, -1, -1 },
138 		.gate = { CGU_REG_CLKGR, 6 },
139 	},
140 
141 	[JZ4740_CLK_SPI] = {
142 		"spi", CGU_CLK_MUX | CGU_CLK_DIV | CGU_CLK_GATE,
143 		.parents = { JZ4740_CLK_EXT, JZ4740_CLK_PLL, -1, -1 },
144 		.mux = { CGU_REG_SSICDR, 31, 1 },
145 		.div = { CGU_REG_SSICDR, 0, 1, 4, -1, -1, -1 },
146 		.gate = { CGU_REG_CLKGR, 4 },
147 	},
148 
149 	[JZ4740_CLK_MMC] = {
150 		"mmc", CGU_CLK_DIV | CGU_CLK_GATE,
151 		.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
152 		.div = { CGU_REG_MSCCDR, 0, 1, 5, -1, -1, -1 },
153 		.gate = { CGU_REG_CLKGR, 7 },
154 	},
155 
156 	[JZ4740_CLK_UHC] = {
157 		"uhc", CGU_CLK_DIV | CGU_CLK_GATE,
158 		.parents = { JZ4740_CLK_PLL_HALF, -1, -1, -1 },
159 		.div = { CGU_REG_UHCCDR, 0, 1, 4, -1, -1, -1 },
160 		.gate = { CGU_REG_CLKGR, 14 },
161 	},
162 
163 	[JZ4740_CLK_UDC] = {
164 		"udc", CGU_CLK_MUX | CGU_CLK_DIV,
165 		.parents = { JZ4740_CLK_EXT, JZ4740_CLK_PLL_HALF, -1, -1 },
166 		.mux = { CGU_REG_CPCCR, 29, 1 },
167 		.div = { CGU_REG_CPCCR, 23, 1, 6, -1, -1, -1 },
168 		.gate = { CGU_REG_SCR, 6 },
169 	},
170 
171 	/* Gate-only clocks */
172 
173 	[JZ4740_CLK_UART0] = {
174 		"uart0", CGU_CLK_GATE,
175 		.parents = { JZ4740_CLK_EXT, -1, -1, -1 },
176 		.gate = { CGU_REG_CLKGR, 0 },
177 	},
178 
179 	[JZ4740_CLK_UART1] = {
180 		"uart1", CGU_CLK_GATE,
181 		.parents = { JZ4740_CLK_EXT, -1, -1, -1 },
182 		.gate = { CGU_REG_CLKGR, 15 },
183 	},
184 
185 	[JZ4740_CLK_DMA] = {
186 		"dma", CGU_CLK_GATE,
187 		.parents = { JZ4740_CLK_PCLK, -1, -1, -1 },
188 		.gate = { CGU_REG_CLKGR, 12 },
189 	},
190 
191 	[JZ4740_CLK_IPU] = {
192 		"ipu", CGU_CLK_GATE,
193 		.parents = { JZ4740_CLK_PCLK, -1, -1, -1 },
194 		.gate = { CGU_REG_CLKGR, 13 },
195 	},
196 
197 	[JZ4740_CLK_ADC] = {
198 		"adc", CGU_CLK_GATE,
199 		.parents = { JZ4740_CLK_EXT, -1, -1, -1 },
200 		.gate = { CGU_REG_CLKGR, 8 },
201 	},
202 
203 	[JZ4740_CLK_I2C] = {
204 		"i2c", CGU_CLK_GATE,
205 		.parents = { JZ4740_CLK_EXT, -1, -1, -1 },
206 		.gate = { CGU_REG_CLKGR, 3 },
207 	},
208 
209 	[JZ4740_CLK_AIC] = {
210 		"aic", CGU_CLK_GATE,
211 		.parents = { JZ4740_CLK_EXT, -1, -1, -1 },
212 		.gate = { CGU_REG_CLKGR, 5 },
213 	},
214 };
215 
216 static void __init jz4740_cgu_init(struct device_node *np)
217 {
218 	int retval;
219 
220 	cgu = ingenic_cgu_new(jz4740_cgu_clocks,
221 			      ARRAY_SIZE(jz4740_cgu_clocks), np);
222 	if (!cgu) {
223 		pr_err("%s: failed to initialise CGU\n", __func__);
224 		return;
225 	}
226 
227 	retval = ingenic_cgu_register_clocks(cgu);
228 	if (retval)
229 		pr_err("%s: failed to register CGU Clocks\n", __func__);
230 }
231 CLK_OF_DECLARE(jz4740_cgu, "ingenic,jz4740-cgu", jz4740_cgu_init);
232 
233 void jz4740_clock_set_wait_mode(enum jz4740_wait_mode mode)
234 {
235 	uint32_t lcr = readl(cgu->base + CGU_REG_LCR);
236 
237 	switch (mode) {
238 	case JZ4740_WAIT_MODE_IDLE:
239 		lcr &= ~LCR_SLEEP;
240 		break;
241 
242 	case JZ4740_WAIT_MODE_SLEEP:
243 		lcr |= LCR_SLEEP;
244 		break;
245 	}
246 
247 	writel(lcr, cgu->base + CGU_REG_LCR);
248 }
249 
250 void jz4740_clock_udc_disable_auto_suspend(void)
251 {
252 	uint32_t clkgr = readl(cgu->base + CGU_REG_CLKGR);
253 
254 	clkgr &= ~CLKGR_UDC;
255 	writel(clkgr, cgu->base + CGU_REG_CLKGR);
256 }
257 EXPORT_SYMBOL_GPL(jz4740_clock_udc_disable_auto_suspend);
258 
259 void jz4740_clock_udc_enable_auto_suspend(void)
260 {
261 	uint32_t clkgr = readl(cgu->base + CGU_REG_CLKGR);
262 
263 	clkgr |= CLKGR_UDC;
264 	writel(clkgr, cgu->base + CGU_REG_CLKGR);
265 }
266 EXPORT_SYMBOL_GPL(jz4740_clock_udc_enable_auto_suspend);
267 
268 #define JZ_CLOCK_GATE_UART0	BIT(0)
269 #define JZ_CLOCK_GATE_TCU	BIT(1)
270 #define JZ_CLOCK_GATE_DMAC	BIT(12)
271 
272 void jz4740_clock_suspend(void)
273 {
274 	uint32_t clkgr, cppcr;
275 
276 	clkgr = readl(cgu->base + CGU_REG_CLKGR);
277 	clkgr |= JZ_CLOCK_GATE_TCU | JZ_CLOCK_GATE_DMAC | JZ_CLOCK_GATE_UART0;
278 	writel(clkgr, cgu->base + CGU_REG_CLKGR);
279 
280 	cppcr = readl(cgu->base + CGU_REG_CPPCR);
281 	cppcr &= ~BIT(jz4740_cgu_clocks[JZ4740_CLK_PLL].pll.enable_bit);
282 	writel(cppcr, cgu->base + CGU_REG_CPPCR);
283 }
284 
285 void jz4740_clock_resume(void)
286 {
287 	uint32_t clkgr, cppcr, stable;
288 
289 	cppcr = readl(cgu->base + CGU_REG_CPPCR);
290 	cppcr |= BIT(jz4740_cgu_clocks[JZ4740_CLK_PLL].pll.enable_bit);
291 	writel(cppcr, cgu->base + CGU_REG_CPPCR);
292 
293 	stable = BIT(jz4740_cgu_clocks[JZ4740_CLK_PLL].pll.stable_bit);
294 	do {
295 		cppcr = readl(cgu->base + CGU_REG_CPPCR);
296 	} while (!(cppcr & stable));
297 
298 	clkgr = readl(cgu->base + CGU_REG_CLKGR);
299 	clkgr &= ~JZ_CLOCK_GATE_TCU;
300 	clkgr &= ~JZ_CLOCK_GATE_DMAC;
301 	clkgr &= ~JZ_CLOCK_GATE_UART0;
302 	writel(clkgr, cgu->base + CGU_REG_CLKGR);
303 }
304