xref: /openbmc/linux/drivers/clk/pxa/clk-pxa25x.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Marvell PXA25x family clocks
4  *
5  * Copyright (C) 2014 Robert Jarzmik
6  *
7  * Heavily inspired from former arch/arm/mach-pxa/pxa25x.c.
8  *
9  * For non-devicetree platforms. Once pxa is fully converted to devicetree, this
10  * should go away.
11  */
12 #include <linux/clk-provider.h>
13 #include <linux/clk.h>
14 #include <linux/clkdev.h>
15 #include <linux/io.h>
16 #include <linux/of.h>
17 #include <mach/pxa2xx-regs.h>
18 #include <mach/smemc.h>
19 
20 #include <dt-bindings/clock/pxa-clock.h>
21 #include "clk-pxa.h"
22 
23 #define KHz 1000
24 #define MHz (1000 * 1000)
25 
26 enum {
27 	PXA_CORE_RUN = 0,
28 	PXA_CORE_TURBO,
29 };
30 
31 #define PXA25x_CLKCFG(T)			\
32 	(CLKCFG_FCS |				\
33 	 ((T) ? CLKCFG_TURBO : 0))
34 #define PXA25x_CCCR(N2, M, L) (N2 << 7 | M << 5 | L)
35 
36 #define MDCNFG_DRAC2(mdcnfg)	(((mdcnfg) >> 21) & 0x3)
37 #define MDCNFG_DRAC0(mdcnfg)	(((mdcnfg) >> 5) & 0x3)
38 
39 /* Define the refresh period in mSec for the SDRAM and the number of rows */
40 #define SDRAM_TREF	64	/* standard 64ms SDRAM */
41 
42 /*
43  * Various clock factors driven by the CCCR register.
44  */
45 
46 /* Crystal Frequency to Memory Frequency Multiplier (L) */
47 static unsigned char L_clk_mult[32] = { 0, 27, 32, 36, 40, 45, 0, };
48 
49 /* Memory Frequency to Run Mode Frequency Multiplier (M) */
50 static unsigned char M_clk_mult[4] = { 0, 1, 2, 4 };
51 
52 /* Run Mode Frequency to Turbo Mode Frequency Multiplier (N) */
53 /* Note: we store the value N * 2 here. */
54 static unsigned char N2_clk_mult[8] = { 0, 0, 2, 3, 4, 0, 6, 0 };
55 
56 static const char * const get_freq_khz[] = {
57 	"core", "run", "cpll", "memory"
58 };
59 
60 static int get_sdram_rows(void)
61 {
62 	static int sdram_rows;
63 	unsigned int drac2 = 0, drac0 = 0;
64 	u32 mdcnfg;
65 
66 	if (sdram_rows)
67 		return sdram_rows;
68 
69 	mdcnfg = readl_relaxed(MDCNFG);
70 
71 	if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3))
72 		drac2 = MDCNFG_DRAC2(mdcnfg);
73 
74 	if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1))
75 		drac0 = MDCNFG_DRAC0(mdcnfg);
76 
77 	sdram_rows = 1 << (11 + max(drac0, drac2));
78 	return sdram_rows;
79 }
80 
81 static u32 mdrefr_dri(unsigned int freq_khz)
82 {
83 	u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows();
84 
85 	return interval / 32;
86 }
87 
88 /*
89  * Get the clock frequency as reflected by CCCR and the turbo flag.
90  * We assume these values have been applied via a fcs.
91  * If info is not 0 we also display the current settings.
92  */
93 unsigned int pxa25x_get_clk_frequency_khz(int info)
94 {
95 	struct clk *clk;
96 	unsigned long clks[5];
97 	int i;
98 
99 	for (i = 0; i < ARRAY_SIZE(get_freq_khz); i++) {
100 		clk = clk_get(NULL, get_freq_khz[i]);
101 		if (IS_ERR(clk)) {
102 			clks[i] = 0;
103 		} else {
104 			clks[i] = clk_get_rate(clk);
105 			clk_put(clk);
106 		}
107 	}
108 
109 	if (info) {
110 		pr_info("Run Mode clock: %ld.%02ldMHz\n",
111 			clks[1] / 1000000, (clks[1] % 1000000) / 10000);
112 		pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
113 			clks[2] / 1000000, (clks[2] % 1000000) / 10000);
114 		pr_info("Memory clock: %ld.%02ldMHz\n",
115 			clks[3] / 1000000, (clks[3] % 1000000) / 10000);
116 	}
117 
118 	return (unsigned int)clks[0] / KHz;
119 }
120 
121 static unsigned long clk_pxa25x_memory_get_rate(struct clk_hw *hw,
122 						unsigned long parent_rate)
123 {
124 	unsigned long cccr = readl(CCCR);
125 	unsigned int m = M_clk_mult[(cccr >> 5) & 0x03];
126 
127 	return parent_rate / m;
128 }
129 PARENTS(clk_pxa25x_memory) = { "run" };
130 RATE_RO_OPS(clk_pxa25x_memory, "memory");
131 
132 PARENTS(pxa25x_pbus95) = { "ppll_95_85mhz", "ppll_95_85mhz" };
133 PARENTS(pxa25x_pbus147) = { "ppll_147_46mhz", "ppll_147_46mhz" };
134 PARENTS(pxa25x_osc3) = { "osc_3_6864mhz", "osc_3_6864mhz" };
135 
136 #define PXA25X_CKEN(dev_id, con_id, parents, mult, div,			\
137 		    bit, is_lp, flags)					\
138 	PXA_CKEN(dev_id, con_id, bit, parents, mult, div, mult, div,	\
139 		 is_lp,  CKEN, CKEN_ ## bit, flags)
140 #define PXA25X_PBUS95_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)	\
141 	PXA25X_CKEN(dev_id, con_id, pxa25x_pbus95_parents, mult_hp,	\
142 		    div_hp, bit, NULL, 0)
143 #define PXA25X_PBUS147_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)\
144 	PXA25X_CKEN(dev_id, con_id, pxa25x_pbus147_parents, mult_hp,	\
145 		    div_hp, bit, NULL, 0)
146 #define PXA25X_OSC3_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)	\
147 	PXA25X_CKEN(dev_id, con_id, pxa25x_osc3_parents, mult_hp,	\
148 		    div_hp, bit, NULL, 0)
149 
150 #define PXA25X_CKEN_1RATE(dev_id, con_id, bit, parents, delay)		\
151 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
152 		       CKEN, CKEN_ ## bit, 0)
153 #define PXA25X_CKEN_1RATE_AO(dev_id, con_id, bit, parents, delay)	\
154 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
155 		       CKEN, CKEN_ ## bit, CLK_IGNORE_UNUSED)
156 
157 static struct desc_clk_cken pxa25x_clocks[] __initdata = {
158 	PXA25X_PBUS95_CKEN("pxa2xx-mci.0", NULL, MMC, 1, 5, 0),
159 	PXA25X_PBUS95_CKEN("pxa2xx-i2c.0", NULL, I2C, 1, 3, 0),
160 	PXA25X_PBUS95_CKEN("pxa2xx-ir", "FICPCLK", FICP, 1, 2, 0),
161 	PXA25X_PBUS95_CKEN("pxa25x-udc", NULL, USB, 1, 2, 5),
162 	PXA25X_PBUS147_CKEN("pxa2xx-uart.0", NULL, FFUART, 1, 10, 1),
163 	PXA25X_PBUS147_CKEN("pxa2xx-uart.1", NULL, BTUART, 1, 10, 1),
164 	PXA25X_PBUS147_CKEN("pxa2xx-uart.2", NULL, STUART, 1, 10, 1),
165 	PXA25X_PBUS147_CKEN("pxa2xx-uart.3", NULL, HWUART, 1, 10, 1),
166 	PXA25X_PBUS147_CKEN("pxa2xx-i2s", NULL, I2S, 1, 10, 0),
167 	PXA25X_PBUS147_CKEN(NULL, "AC97CLK", AC97, 1, 12, 0),
168 	PXA25X_OSC3_CKEN("pxa25x-ssp.0", NULL, SSP, 1, 1, 0),
169 	PXA25X_OSC3_CKEN("pxa25x-nssp.1", NULL, NSSP, 1, 1, 0),
170 	PXA25X_OSC3_CKEN("pxa25x-nssp.2", NULL, ASSP, 1, 1, 0),
171 	PXA25X_OSC3_CKEN("pxa25x-pwm.0", NULL, PWM0, 1, 1, 0),
172 	PXA25X_OSC3_CKEN("pxa25x-pwm.1", NULL, PWM1, 1, 1, 0),
173 
174 	PXA25X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, clk_pxa25x_memory_parents, 0),
175 	PXA25X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
176 			     clk_pxa25x_memory_parents, 0),
177 };
178 
179 /*
180  * In this table, PXA25x_CCCR(N2, M, L) has the following meaning, where :
181  *   - freq_cpll = n * m * L * 3.6864 MHz
182  *   - n = N2 / 2
183  *   - m = 2^(M - 1), where 1 <= M <= 3
184  *   - l = L_clk_mult[L], ie. { 0, 27, 32, 36, 40, 45, 0, }[L]
185  */
186 static struct pxa2xx_freq pxa25x_freqs[] = {
187 	/* CPU  MEMBUS  CCCR                  DIV2 CCLKCFG      */
188 	{ 99532800, 99500, PXA25x_CCCR(2,  1, 1),  1, PXA25x_CLKCFG(1)},
189 	{199065600, 99500, PXA25x_CCCR(4,  1, 1),  0, PXA25x_CLKCFG(1)},
190 	{298598400, 99500, PXA25x_CCCR(3,  2, 1),  0, PXA25x_CLKCFG(1)},
191 	{398131200, 99500, PXA25x_CCCR(4,  2, 1),  0, PXA25x_CLKCFG(1)},
192 };
193 
194 static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw)
195 {
196 	unsigned long clkcfg;
197 	unsigned int t;
198 
199 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
200 	t  = clkcfg & (1 << 0);
201 	if (t)
202 		return PXA_CORE_TURBO;
203 	return PXA_CORE_RUN;
204 }
205 
206 static int clk_pxa25x_core_set_parent(struct clk_hw *hw, u8 index)
207 {
208 	if (index > PXA_CORE_TURBO)
209 		return -EINVAL;
210 
211 	pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO);
212 
213 	return 0;
214 }
215 
216 static int clk_pxa25x_core_determine_rate(struct clk_hw *hw,
217 					  struct clk_rate_request *req)
218 {
219 	return __clk_mux_determine_rate(hw, req);
220 }
221 
222 PARENTS(clk_pxa25x_core) = { "run", "cpll" };
223 MUX_OPS(clk_pxa25x_core, "core", CLK_SET_RATE_PARENT);
224 
225 static unsigned long clk_pxa25x_run_get_rate(struct clk_hw *hw,
226 					     unsigned long parent_rate)
227 {
228 	unsigned long cccr = readl(CCCR);
229 	unsigned int n2 = N2_clk_mult[(cccr >> 7) & 0x07];
230 
231 	return (parent_rate / n2) * 2;
232 }
233 PARENTS(clk_pxa25x_run) = { "cpll" };
234 RATE_RO_OPS(clk_pxa25x_run, "run");
235 
236 static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw,
237 	unsigned long parent_rate)
238 {
239 	unsigned long clkcfg, cccr = readl(CCCR);
240 	unsigned int l, m, n2, t;
241 
242 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
243 	t = clkcfg & (1 << 0);
244 	l  =  L_clk_mult[(cccr >> 0) & 0x1f];
245 	m = M_clk_mult[(cccr >> 5) & 0x03];
246 	n2 = N2_clk_mult[(cccr >> 7) & 0x07];
247 
248 	return m * l * n2 * parent_rate / 2;
249 }
250 
251 static int clk_pxa25x_cpll_determine_rate(struct clk_hw *hw,
252 					  struct clk_rate_request *req)
253 {
254 	return pxa2xx_determine_rate(req, pxa25x_freqs,
255 				     ARRAY_SIZE(pxa25x_freqs));
256 }
257 
258 static int clk_pxa25x_cpll_set_rate(struct clk_hw *hw, unsigned long rate,
259 				    unsigned long parent_rate)
260 {
261 	int i;
262 
263 	pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate);
264 	for (i = 0; i < ARRAY_SIZE(pxa25x_freqs); i++)
265 		if (pxa25x_freqs[i].cpll == rate)
266 			break;
267 
268 	if (i >= ARRAY_SIZE(pxa25x_freqs))
269 		return -EINVAL;
270 
271 	pxa2xx_cpll_change(&pxa25x_freqs[i], mdrefr_dri, MDREFR, CCCR);
272 
273 	return 0;
274 }
275 PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" };
276 RATE_OPS(clk_pxa25x_cpll, "cpll");
277 
278 static void __init pxa25x_register_core(void)
279 {
280 	clkdev_pxa_register(CLK_NONE, "cpll", NULL,
281 			    clk_register_clk_pxa25x_cpll());
282 	clkdev_pxa_register(CLK_NONE, "run", NULL,
283 			    clk_register_clk_pxa25x_run());
284 	clkdev_pxa_register(CLK_CORE, "core", NULL,
285 			    clk_register_clk_pxa25x_core());
286 }
287 
288 static void __init pxa25x_register_plls(void)
289 {
290 	clk_register_fixed_rate(NULL, "osc_3_6864mhz", NULL,
291 				CLK_GET_RATE_NOCACHE, 3686400);
292 	clkdev_pxa_register(CLK_OSC32k768, "osc_32_768khz", NULL,
293 			    clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
294 						    CLK_GET_RATE_NOCACHE,
295 						    32768));
296 	clk_register_fixed_rate(NULL, "clk_dummy", NULL, 0, 0);
297 	clk_register_fixed_factor(NULL, "ppll_95_85mhz", "osc_3_6864mhz",
298 				  0, 26, 1);
299 	clk_register_fixed_factor(NULL, "ppll_147_46mhz", "osc_3_6864mhz",
300 				  0, 40, 1);
301 }
302 
303 static void __init pxa25x_base_clocks_init(void)
304 {
305 	pxa25x_register_plls();
306 	pxa25x_register_core();
307 	clkdev_pxa_register(CLK_NONE, "system_bus", NULL,
308 			    clk_register_clk_pxa25x_memory());
309 }
310 
311 #define DUMMY_CLK(_con_id, _dev_id, _parent) \
312 	{ .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
313 struct dummy_clk {
314 	const char *con_id;
315 	const char *dev_id;
316 	const char *parent;
317 };
318 static struct dummy_clk dummy_clks[] __initdata = {
319 	DUMMY_CLK(NULL, "pxa25x-gpio", "osc_32_768khz"),
320 	DUMMY_CLK(NULL, "pxa26x-gpio", "osc_32_768khz"),
321 	DUMMY_CLK("GPIO11_CLK", NULL, "osc_3_6864mhz"),
322 	DUMMY_CLK("GPIO12_CLK", NULL, "osc_32_768khz"),
323 	DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
324 	DUMMY_CLK("OSTIMER0", NULL, "osc_3_6864mhz"),
325 	DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
326 };
327 
328 static void __init pxa25x_dummy_clocks_init(void)
329 {
330 	struct clk *clk;
331 	struct dummy_clk *d;
332 	const char *name;
333 	int i;
334 
335 	/*
336 	 * All pinctrl logic has been wiped out of the clock driver, especially
337 	 * for gpio11 and gpio12 outputs. Machine code should ensure proper pin
338 	 * control (ie. pxa2xx_mfp_config() invocation).
339 	 */
340 	for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
341 		d = &dummy_clks[i];
342 		name = d->dev_id ? d->dev_id : d->con_id;
343 		clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
344 		clk_register_clkdev(clk, d->con_id, d->dev_id);
345 	}
346 }
347 
348 int __init pxa25x_clocks_init(void)
349 {
350 	pxa25x_base_clocks_init();
351 	pxa25x_dummy_clocks_init();
352 	return clk_pxa_cken_init(pxa25x_clocks, ARRAY_SIZE(pxa25x_clocks));
353 }
354 
355 static void __init pxa25x_dt_clocks_init(struct device_node *np)
356 {
357 	pxa25x_clocks_init();
358 	clk_pxa_dt_common_init(np);
359 }
360 CLK_OF_DECLARE(pxa25x_clks, "marvell,pxa250-core-clocks",
361 	       pxa25x_dt_clocks_init);
362