xref: /openbmc/linux/drivers/clk/pxa/clk-pxa25x.c (revision 5e29a910)
1 /*
2  * Marvell PXA25x family clocks
3  *
4  * Copyright (C) 2014 Robert Jarzmik
5  *
6  * Heavily inspired from former arch/arm/mach-pxa/pxa25x.c.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; version 2 of the License.
11  *
12  * For non-devicetree platforms. Once pxa is fully converted to devicetree, this
13  * should go away.
14  */
15 #include <linux/clk-provider.h>
16 #include <linux/clk.h>
17 #include <linux/clkdev.h>
18 #include <linux/io.h>
19 #include <linux/of.h>
20 #include <mach/pxa25x.h>
21 #include <mach/pxa2xx-regs.h>
22 
23 #include <dt-bindings/clock/pxa-clock.h>
24 #include "clk-pxa.h"
25 
26 #define KHz 1000
27 #define MHz (1000 * 1000)
28 
29 enum {
30 	PXA_CORE_RUN = 0,
31 	PXA_CORE_TURBO,
32 };
33 
34 /*
35  * Various clock factors driven by the CCCR register.
36  */
37 
38 /* Crystal Frequency to Memory Frequency Multiplier (L) */
39 static unsigned char L_clk_mult[32] = { 0, 27, 32, 36, 40, 45, 0, };
40 
41 /* Memory Frequency to Run Mode Frequency Multiplier (M) */
42 static unsigned char M_clk_mult[4] = { 0, 1, 2, 4 };
43 
44 /* Run Mode Frequency to Turbo Mode Frequency Multiplier (N) */
45 /* Note: we store the value N * 2 here. */
46 static unsigned char N2_clk_mult[8] = { 0, 0, 2, 3, 4, 0, 6, 0 };
47 
48 static const char * const get_freq_khz[] = {
49 	"core", "run", "cpll", "memory"
50 };
51 
52 /*
53  * Get the clock frequency as reflected by CCCR and the turbo flag.
54  * We assume these values have been applied via a fcs.
55  * If info is not 0 we also display the current settings.
56  */
57 unsigned int pxa25x_get_clk_frequency_khz(int info)
58 {
59 	struct clk *clk;
60 	unsigned long clks[5];
61 	int i;
62 
63 	for (i = 0; i < ARRAY_SIZE(get_freq_khz); i++) {
64 		clk = clk_get(NULL, get_freq_khz[i]);
65 		if (IS_ERR(clk)) {
66 			clks[i] = 0;
67 		} else {
68 			clks[i] = clk_get_rate(clk);
69 			clk_put(clk);
70 		}
71 	}
72 
73 	if (info) {
74 		pr_info("Run Mode clock: %ld.%02ldMHz\n",
75 			clks[1] / 1000000, (clks[1] % 1000000) / 10000);
76 		pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
77 			clks[2] / 1000000, (clks[2] % 1000000) / 10000);
78 		pr_info("Memory clock: %ld.%02ldMHz\n",
79 			clks[3] / 1000000, (clks[3] % 1000000) / 10000);
80 	}
81 
82 	return (unsigned int)clks[0];
83 }
84 
85 static unsigned long clk_pxa25x_memory_get_rate(struct clk_hw *hw,
86 						unsigned long parent_rate)
87 {
88 	unsigned long cccr = CCCR;
89 	unsigned int m = M_clk_mult[(cccr >> 5) & 0x03];
90 
91 	return parent_rate / m;
92 }
93 PARENTS(clk_pxa25x_memory) = { "run" };
94 RATE_RO_OPS(clk_pxa25x_memory, "memory");
95 
96 PARENTS(pxa25x_pbus95) = { "ppll_95_85mhz", "ppll_95_85mhz" };
97 PARENTS(pxa25x_pbus147) = { "ppll_147_46mhz", "ppll_147_46mhz" };
98 PARENTS(pxa25x_osc3) = { "osc_3_6864mhz", "osc_3_6864mhz" };
99 
100 #define PXA25X_CKEN(dev_id, con_id, parents, mult, div,			\
101 		    bit, is_lp, flags)					\
102 	PXA_CKEN(dev_id, con_id, bit, parents, mult, div, mult, div,	\
103 		 is_lp,  &CKEN, CKEN_ ## bit, flags)
104 #define PXA25X_PBUS95_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)	\
105 	PXA25X_CKEN(dev_id, con_id, pxa25x_pbus95_parents, mult_hp,	\
106 		    div_hp, bit, NULL, 0)
107 #define PXA25X_PBUS147_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)\
108 	PXA25X_CKEN(dev_id, con_id, pxa25x_pbus147_parents, mult_hp,	\
109 		    div_hp, bit, NULL, 0)
110 #define PXA25X_OSC3_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)	\
111 	PXA25X_CKEN(dev_id, con_id, pxa25x_osc3_parents, mult_hp,	\
112 		    div_hp, bit, NULL, 0)
113 
114 #define PXA25X_CKEN_1RATE(dev_id, con_id, bit, parents, delay)		\
115 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
116 		       &CKEN, CKEN_ ## bit, 0)
117 #define PXA25X_CKEN_1RATE_AO(dev_id, con_id, bit, parents, delay)	\
118 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
119 		       &CKEN, CKEN_ ## bit, CLK_IGNORE_UNUSED)
120 
121 static struct desc_clk_cken pxa25x_clocks[] __initdata = {
122 	PXA25X_PBUS95_CKEN("pxa2xx-mci.0", NULL, MMC, 1, 5, 0),
123 	PXA25X_PBUS95_CKEN("pxa2xx-i2c.0", NULL, I2C, 1, 3, 0),
124 	PXA25X_PBUS95_CKEN("pxa2xx-ir", "FICPCLK", FICP, 1, 2, 0),
125 	PXA25X_PBUS95_CKEN("pxa25x-udc", NULL, USB, 1, 2, 5),
126 	PXA25X_PBUS147_CKEN("pxa2xx-uart.0", NULL, FFUART, 1, 10, 1),
127 	PXA25X_PBUS147_CKEN("pxa2xx-uart.1", NULL, BTUART, 1, 10, 1),
128 	PXA25X_PBUS147_CKEN("pxa2xx-uart.2", NULL, STUART, 1, 10, 1),
129 	PXA25X_PBUS147_CKEN("pxa2xx-uart.3", NULL, HWUART, 1, 10, 1),
130 	PXA25X_PBUS147_CKEN("pxa2xx-i2s", NULL, I2S, 1, 10, 0),
131 	PXA25X_PBUS147_CKEN(NULL, "AC97CLK", AC97, 1, 12, 0),
132 	PXA25X_OSC3_CKEN("pxa25x-ssp.0", NULL, SSP, 1, 1, 0),
133 	PXA25X_OSC3_CKEN("pxa25x-nssp.1", NULL, NSSP, 1, 1, 0),
134 	PXA25X_OSC3_CKEN("pxa25x-nssp.2", NULL, ASSP, 1, 1, 0),
135 	PXA25X_OSC3_CKEN("pxa25x-pwm.0", NULL, PWM0, 1, 1, 0),
136 	PXA25X_OSC3_CKEN("pxa25x-pwm.1", NULL, PWM1, 1, 1, 0),
137 
138 	PXA25X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, clk_pxa25x_memory_parents, 0),
139 	PXA25X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
140 			     clk_pxa25x_memory_parents, 0),
141 };
142 
143 static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw)
144 {
145 	unsigned long clkcfg;
146 	unsigned int t;
147 
148 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
149 	t  = clkcfg & (1 << 0);
150 	if (t)
151 		return PXA_CORE_TURBO;
152 	return PXA_CORE_RUN;
153 }
154 
155 static unsigned long clk_pxa25x_core_get_rate(struct clk_hw *hw,
156 					      unsigned long parent_rate)
157 {
158 	return parent_rate;
159 }
160 PARENTS(clk_pxa25x_core) = { "run", "cpll" };
161 MUX_RO_RATE_RO_OPS(clk_pxa25x_core, "core");
162 
163 static unsigned long clk_pxa25x_run_get_rate(struct clk_hw *hw,
164 					     unsigned long parent_rate)
165 {
166 	unsigned long cccr = CCCR;
167 	unsigned int n2 = N2_clk_mult[(cccr >> 7) & 0x07];
168 
169 	return (parent_rate / n2) * 2;
170 }
171 PARENTS(clk_pxa25x_run) = { "cpll" };
172 RATE_RO_OPS(clk_pxa25x_run, "run");
173 
174 static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw,
175 	unsigned long parent_rate)
176 {
177 	unsigned long clkcfg, cccr = CCCR;
178 	unsigned int l, m, n2, t;
179 
180 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
181 	t = clkcfg & (1 << 0);
182 	l  =  L_clk_mult[(cccr >> 0) & 0x1f];
183 	m = M_clk_mult[(cccr >> 5) & 0x03];
184 	n2 = N2_clk_mult[(cccr >> 7) & 0x07];
185 
186 	if (t)
187 		return m * l * n2 * parent_rate / 2;
188 	return m * l * parent_rate;
189 }
190 PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" };
191 RATE_RO_OPS(clk_pxa25x_cpll, "cpll");
192 
193 static void __init pxa25x_register_core(void)
194 {
195 	clk_register_clk_pxa25x_cpll();
196 	clk_register_clk_pxa25x_run();
197 	clkdev_pxa_register(CLK_CORE, "core", NULL,
198 			    clk_register_clk_pxa25x_core());
199 }
200 
201 static void __init pxa25x_register_plls(void)
202 {
203 	clk_register_fixed_rate(NULL, "osc_3_6864mhz", NULL,
204 				CLK_GET_RATE_NOCACHE | CLK_IS_ROOT,
205 				3686400);
206 	clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
207 				CLK_GET_RATE_NOCACHE | CLK_IS_ROOT,
208 				32768);
209 	clk_register_fixed_rate(NULL, "clk_dummy", NULL, CLK_IS_ROOT, 0);
210 	clk_register_fixed_factor(NULL, "ppll_95_85mhz", "osc_3_6864mhz",
211 				  0, 26, 1);
212 	clk_register_fixed_factor(NULL, "ppll_147_46mhz", "osc_3_6864mhz",
213 				  0, 40, 1);
214 }
215 
216 static void __init pxa25x_base_clocks_init(void)
217 {
218 	pxa25x_register_plls();
219 	pxa25x_register_core();
220 	clk_register_clk_pxa25x_memory();
221 }
222 
223 #define DUMMY_CLK(_con_id, _dev_id, _parent) \
224 	{ .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
225 struct dummy_clk {
226 	const char *con_id;
227 	const char *dev_id;
228 	const char *parent;
229 };
230 static struct dummy_clk dummy_clks[] __initdata = {
231 	DUMMY_CLK(NULL, "pxa25x-gpio", "osc_32_768khz"),
232 	DUMMY_CLK(NULL, "pxa26x-gpio", "osc_32_768khz"),
233 	DUMMY_CLK("GPIO11_CLK", NULL, "osc_3_6864mhz"),
234 	DUMMY_CLK("GPIO12_CLK", NULL, "osc_32_768khz"),
235 	DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
236 	DUMMY_CLK("OSTIMER0", NULL, "osc_32_768khz"),
237 	DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
238 };
239 
240 static void __init pxa25x_dummy_clocks_init(void)
241 {
242 	struct clk *clk;
243 	struct dummy_clk *d;
244 	const char *name;
245 	int i;
246 
247 	/*
248 	 * All pinctrl logic has been wiped out of the clock driver, especially
249 	 * for gpio11 and gpio12 outputs. Machine code should ensure proper pin
250 	 * control (ie. pxa2xx_mfp_config() invocation).
251 	 */
252 	for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
253 		d = &dummy_clks[i];
254 		name = d->dev_id ? d->dev_id : d->con_id;
255 		clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
256 		clk_register_clkdev(clk, d->con_id, d->dev_id);
257 	}
258 }
259 
260 int __init pxa25x_clocks_init(void)
261 {
262 	pxa25x_base_clocks_init();
263 	pxa25x_dummy_clocks_init();
264 	return clk_pxa_cken_init(pxa25x_clocks, ARRAY_SIZE(pxa25x_clocks));
265 }
266 
267 static void __init pxa25x_dt_clocks_init(struct device_node *np)
268 {
269 	pxa25x_clocks_init();
270 	clk_pxa_dt_common_init(np);
271 }
272 CLK_OF_DECLARE(pxa25x_clks, "marvell,pxa250-core-clocks",
273 	       pxa25x_dt_clocks_init);
274