xref: /openbmc/linux/drivers/clk/pxa/clk-pxa27x.c (revision 7f6964c5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Marvell PXA27x family clocks
4  *
5  * Copyright (C) 2014 Robert Jarzmik
6  *
7  * Heavily inspired from former arch/arm/mach-pxa/clock.c.
8  */
9 #include <linux/clk-provider.h>
10 #include <mach/pxa2xx-regs.h>
11 #include <linux/io.h>
12 #include <linux/clk.h>
13 #include <linux/clkdev.h>
14 #include <linux/of.h>
15 
16 #include <mach/smemc.h>
17 
18 #include <dt-bindings/clock/pxa-clock.h>
19 #include "clk-pxa.h"
20 
21 #define KHz 1000
22 #define MHz (1000 * 1000)
23 
24 enum {
25 	PXA_CORE_13Mhz = 0,
26 	PXA_CORE_RUN,
27 	PXA_CORE_TURBO,
28 };
29 
30 enum {
31 	PXA_BUS_13Mhz = 0,
32 	PXA_BUS_RUN,
33 };
34 
35 enum {
36 	PXA_LCD_13Mhz = 0,
37 	PXA_LCD_RUN,
38 };
39 
40 enum {
41 	PXA_MEM_13Mhz = 0,
42 	PXA_MEM_SYSTEM_BUS,
43 	PXA_MEM_RUN,
44 };
45 
46 #define PXA27x_CLKCFG(B, HT, T)			\
47 	(CLKCFG_FCS |				\
48 	 ((B)  ? CLKCFG_FASTBUS : 0) |		\
49 	 ((HT) ? CLKCFG_HALFTURBO : 0) |	\
50 	 ((T)  ? CLKCFG_TURBO : 0))
51 #define PXA27x_CCCR(A, L, N2) (A << 25 | N2 << 7 | L)
52 
53 #define MDCNFG_DRAC2(mdcnfg)	(((mdcnfg) >> 21) & 0x3)
54 #define MDCNFG_DRAC0(mdcnfg)	(((mdcnfg) >> 5) & 0x3)
55 
56 /* Define the refresh period in mSec for the SDRAM and the number of rows */
57 #define SDRAM_TREF	64	/* standard 64ms SDRAM */
58 
59 static const char * const get_freq_khz[] = {
60 	"core", "run", "cpll", "memory",
61 	"system_bus"
62 };
63 
64 static int get_sdram_rows(void)
65 {
66 	static int sdram_rows;
67 	unsigned int drac2 = 0, drac0 = 0;
68 	u32 mdcnfg;
69 
70 	if (sdram_rows)
71 		return sdram_rows;
72 
73 	mdcnfg = readl_relaxed(MDCNFG);
74 
75 	if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3))
76 		drac2 = MDCNFG_DRAC2(mdcnfg);
77 
78 	if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1))
79 		drac0 = MDCNFG_DRAC0(mdcnfg);
80 
81 	sdram_rows = 1 << (11 + max(drac0, drac2));
82 	return sdram_rows;
83 }
84 
85 static u32 mdrefr_dri(unsigned int freq_khz)
86 {
87 	u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows();
88 
89 	return (interval - 31) / 32;
90 }
91 
92 /*
93  * Get the clock frequency as reflected by CCSR and the turbo flag.
94  * We assume these values have been applied via a fcs.
95  * If info is not 0 we also display the current settings.
96  */
97 unsigned int pxa27x_get_clk_frequency_khz(int info)
98 {
99 	struct clk *clk;
100 	unsigned long clks[5];
101 	int i;
102 
103 	for (i = 0; i < 5; i++) {
104 		clk = clk_get(NULL, get_freq_khz[i]);
105 		if (IS_ERR(clk)) {
106 			clks[i] = 0;
107 		} else {
108 			clks[i] = clk_get_rate(clk);
109 			clk_put(clk);
110 		}
111 	}
112 	if (info) {
113 		pr_info("Run Mode clock: %ld.%02ldMHz\n",
114 			clks[1] / 1000000, (clks[1] % 1000000) / 10000);
115 		pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
116 			clks[2] / 1000000, (clks[2] % 1000000) / 10000);
117 		pr_info("Memory clock: %ld.%02ldMHz\n",
118 			clks[3] / 1000000, (clks[3] % 1000000) / 10000);
119 		pr_info("System bus clock: %ld.%02ldMHz\n",
120 			clks[4] / 1000000, (clks[4] % 1000000) / 10000);
121 	}
122 	return (unsigned int)clks[0] / KHz;
123 }
124 
125 bool pxa27x_is_ppll_disabled(void)
126 {
127 	unsigned long ccsr = readl(CCSR);
128 
129 	return ccsr & (1 << CCCR_PPDIS_BIT);
130 }
131 
132 #define PXA27X_CKEN(dev_id, con_id, parents, mult_hp, div_hp,		\
133 		    bit, is_lp, flags)					\
134 	PXA_CKEN(dev_id, con_id, bit, parents, 1, 1, mult_hp, div_hp,	\
135 		 is_lp,  CKEN, CKEN_ ## bit, flags)
136 #define PXA27X_PBUS_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)	\
137 	PXA27X_CKEN(dev_id, con_id, pxa27x_pbus_parents, mult_hp,	\
138 		    div_hp, bit, pxa27x_is_ppll_disabled, 0)
139 
140 PARENTS(pxa27x_pbus) = { "osc_13mhz", "ppll_312mhz" };
141 PARENTS(pxa27x_sbus) = { "system_bus", "system_bus" };
142 PARENTS(pxa27x_32Mhz_bus) = { "osc_32_768khz", "osc_32_768khz" };
143 PARENTS(pxa27x_lcd_bus) = { "lcd_base", "lcd_base" };
144 PARENTS(pxa27x_membus) = { "lcd_base", "lcd_base" };
145 
146 #define PXA27X_CKEN_1RATE(dev_id, con_id, bit, parents, delay)		\
147 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
148 		       CKEN, CKEN_ ## bit, 0)
149 #define PXA27X_CKEN_1RATE_AO(dev_id, con_id, bit, parents, delay)	\
150 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
151 		       CKEN, CKEN_ ## bit, CLK_IGNORE_UNUSED)
152 
153 static struct desc_clk_cken pxa27x_clocks[] __initdata = {
154 	PXA27X_PBUS_CKEN("pxa2xx-uart.0", NULL, FFUART, 2, 42, 1),
155 	PXA27X_PBUS_CKEN("pxa2xx-uart.1", NULL, BTUART, 2, 42, 1),
156 	PXA27X_PBUS_CKEN("pxa2xx-uart.2", NULL, STUART, 2, 42, 1),
157 	PXA27X_PBUS_CKEN("pxa2xx-i2s", NULL, I2S, 2, 51, 0),
158 	PXA27X_PBUS_CKEN("pxa2xx-i2c.0", NULL, I2C, 2, 19, 0),
159 	PXA27X_PBUS_CKEN("pxa27x-udc", NULL, USB, 2, 13, 5),
160 	PXA27X_PBUS_CKEN("pxa2xx-mci.0", NULL, MMC, 2, 32, 0),
161 	PXA27X_PBUS_CKEN("pxa2xx-ir", "FICPCLK", FICP, 2, 13, 0),
162 	PXA27X_PBUS_CKEN("pxa27x-ohci", NULL, USBHOST, 2, 13, 0),
163 	PXA27X_PBUS_CKEN("pxa2xx-i2c.1", NULL, PWRI2C, 1, 24, 0),
164 	PXA27X_PBUS_CKEN("pxa27x-ssp.0", NULL, SSP1, 1, 24, 0),
165 	PXA27X_PBUS_CKEN("pxa27x-ssp.1", NULL, SSP2, 1, 24, 0),
166 	PXA27X_PBUS_CKEN("pxa27x-ssp.2", NULL, SSP3, 1, 24, 0),
167 	PXA27X_PBUS_CKEN("pxa27x-pwm.0", NULL, PWM0, 1, 24, 0),
168 	PXA27X_PBUS_CKEN("pxa27x-pwm.1", NULL, PWM1, 1, 24, 0),
169 	PXA27X_PBUS_CKEN(NULL, "MSLCLK", MSL, 2, 13, 0),
170 	PXA27X_PBUS_CKEN(NULL, "USIMCLK", USIM, 2, 13, 0),
171 	PXA27X_PBUS_CKEN(NULL, "MSTKCLK", MEMSTK, 2, 32, 0),
172 	PXA27X_PBUS_CKEN(NULL, "AC97CLK", AC97, 1, 1, 0),
173 	PXA27X_PBUS_CKEN(NULL, "AC97CONFCLK", AC97CONF, 1, 1, 0),
174 	PXA27X_PBUS_CKEN(NULL, "OSTIMER0", OSTIMER, 1, 96, 0),
175 
176 	PXA27X_CKEN_1RATE("pxa27x-keypad", NULL, KEYPAD,
177 			  pxa27x_32Mhz_bus_parents, 0),
178 	PXA27X_CKEN_1RATE(NULL, "IMCLK", IM, pxa27x_sbus_parents, 0),
179 	PXA27X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, pxa27x_lcd_bus_parents, 0),
180 	PXA27X_CKEN_1RATE("pxa27x-camera.0", NULL, CAMERA,
181 			  pxa27x_lcd_bus_parents, 0),
182 	PXA27X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
183 			     pxa27x_membus_parents, 0),
184 
185 };
186 
187 /*
188  * PXA270 definitions
189  *
190  * For the PXA27x:
191  * Control variables are A, L, 2N for CCCR; B, HT, T for CLKCFG.
192  *
193  * A = 0 => memory controller clock from table 3-7,
194  * A = 1 => memory controller clock = system bus clock
195  * Run mode frequency	= 13 MHz * L
196  * Turbo mode frequency = 13 MHz * L * N
197  * System bus frequency = 13 MHz * L / (B + 1)
198  *
199  * In CCCR:
200  * A = 1
201  * L = 16	  oscillator to run mode ratio
202  * 2N = 6	  2 * (turbo mode to run mode ratio)
203  *
204  * In CCLKCFG:
205  * B = 1	  Fast bus mode
206  * HT = 0	  Half-Turbo mode
207  * T = 1	  Turbo mode
208  *
209  * For now, just support some of the combinations in table 3-7 of
210  * PXA27x Processor Family Developer's Manual to simplify frequency
211  * change sequences.
212  */
213 static struct pxa2xx_freq pxa27x_freqs[] = {
214 	{104000000, 104000, PXA27x_CCCR(1,  8, 2), 0, PXA27x_CLKCFG(1, 0, 1) },
215 	{156000000, 104000, PXA27x_CCCR(1,  8, 3), 0, PXA27x_CLKCFG(1, 0, 1) },
216 	{208000000, 208000, PXA27x_CCCR(0, 16, 2), 1, PXA27x_CLKCFG(0, 0, 1) },
217 	{312000000, 208000, PXA27x_CCCR(1, 16, 3), 1, PXA27x_CLKCFG(1, 0, 1) },
218 	{416000000, 208000, PXA27x_CCCR(1, 16, 4), 1, PXA27x_CLKCFG(1, 0, 1) },
219 	{520000000, 208000, PXA27x_CCCR(1, 16, 5), 1, PXA27x_CLKCFG(1, 0, 1) },
220 	{624000000, 208000, PXA27x_CCCR(1, 16, 6), 1, PXA27x_CLKCFG(1, 0, 1) },
221 };
222 
223 static unsigned long clk_pxa27x_cpll_get_rate(struct clk_hw *hw,
224 	unsigned long parent_rate)
225 {
226 	unsigned long clkcfg;
227 	unsigned int t, ht;
228 	unsigned int l, L, n2, N;
229 	unsigned long ccsr = readl(CCSR);
230 
231 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
232 	t  = clkcfg & (1 << 0);
233 	ht = clkcfg & (1 << 2);
234 
235 	l  = ccsr & CCSR_L_MASK;
236 	n2 = (ccsr & CCSR_N2_MASK) >> CCSR_N2_SHIFT;
237 	L  = l * parent_rate;
238 	N  = (L * n2) / 2;
239 
240 	return N;
241 }
242 
243 static int clk_pxa27x_cpll_determine_rate(struct clk_hw *hw,
244 					  struct clk_rate_request *req)
245 {
246 	return pxa2xx_determine_rate(req, pxa27x_freqs,
247 				     ARRAY_SIZE(pxa27x_freqs));
248 }
249 
250 static int clk_pxa27x_cpll_set_rate(struct clk_hw *hw, unsigned long rate,
251 				    unsigned long parent_rate)
252 {
253 	int i;
254 
255 	pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate);
256 	for (i = 0; i < ARRAY_SIZE(pxa27x_freqs); i++)
257 		if (pxa27x_freqs[i].cpll == rate)
258 			break;
259 
260 	if (i >= ARRAY_SIZE(pxa27x_freqs))
261 		return -EINVAL;
262 
263 	pxa2xx_cpll_change(&pxa27x_freqs[i], mdrefr_dri, MDREFR, CCCR);
264 	return 0;
265 }
266 
267 PARENTS(clk_pxa27x_cpll) = { "osc_13mhz" };
268 RATE_OPS(clk_pxa27x_cpll, "cpll");
269 
270 static unsigned long clk_pxa27x_lcd_base_get_rate(struct clk_hw *hw,
271 						  unsigned long parent_rate)
272 {
273 	unsigned int l, osc_forced;
274 	unsigned long ccsr = readl(CCSR);
275 	unsigned long cccr = readl(CCCR);
276 
277 	l  = ccsr & CCSR_L_MASK;
278 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
279 	if (osc_forced) {
280 		if (cccr & (1 << CCCR_LCD_26_BIT))
281 			return parent_rate * 2;
282 		else
283 			return parent_rate;
284 	}
285 
286 	if (l <= 7)
287 		return parent_rate;
288 	if (l <= 16)
289 		return parent_rate / 2;
290 	return parent_rate / 4;
291 }
292 
293 static u8 clk_pxa27x_lcd_base_get_parent(struct clk_hw *hw)
294 {
295 	unsigned int osc_forced;
296 	unsigned long ccsr = readl(CCSR);
297 
298 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
299 	if (osc_forced)
300 		return PXA_LCD_13Mhz;
301 	else
302 		return PXA_LCD_RUN;
303 }
304 
305 PARENTS(clk_pxa27x_lcd_base) = { "osc_13mhz", "run" };
306 MUX_RO_RATE_RO_OPS(clk_pxa27x_lcd_base, "lcd_base");
307 
308 static void __init pxa27x_register_plls(void)
309 {
310 	clk_register_fixed_rate(NULL, "osc_13mhz", NULL,
311 				CLK_GET_RATE_NOCACHE,
312 				13 * MHz);
313 	clkdev_pxa_register(CLK_OSC32k768, "osc_32_768khz", NULL,
314 			    clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
315 						    CLK_GET_RATE_NOCACHE,
316 						    32768 * KHz));
317 	clk_register_fixed_rate(NULL, "clk_dummy", NULL, 0, 0);
318 	clk_register_fixed_factor(NULL, "ppll_312mhz", "osc_13mhz", 0, 24, 1);
319 }
320 
321 static u8 clk_pxa27x_core_get_parent(struct clk_hw *hw)
322 {
323 	unsigned long clkcfg;
324 	unsigned int t, ht, osc_forced;
325 	unsigned long ccsr = readl(CCSR);
326 
327 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
328 	if (osc_forced)
329 		return PXA_CORE_13Mhz;
330 
331 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
332 	t  = clkcfg & (1 << 0);
333 	ht = clkcfg & (1 << 2);
334 
335 	if (ht || t)
336 		return PXA_CORE_TURBO;
337 	return PXA_CORE_RUN;
338 }
339 
340 static int clk_pxa27x_core_set_parent(struct clk_hw *hw, u8 index)
341 {
342 	if (index > PXA_CORE_TURBO)
343 		return -EINVAL;
344 
345 	pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO);
346 
347 	return 0;
348 }
349 
350 static int clk_pxa27x_core_determine_rate(struct clk_hw *hw,
351 					  struct clk_rate_request *req)
352 {
353 	return __clk_mux_determine_rate(hw, req);
354 }
355 
356 PARENTS(clk_pxa27x_core) = { "osc_13mhz", "run", "cpll" };
357 MUX_OPS(clk_pxa27x_core, "core", CLK_SET_RATE_PARENT);
358 
359 static unsigned long clk_pxa27x_run_get_rate(struct clk_hw *hw,
360 					     unsigned long parent_rate)
361 {
362 	unsigned long ccsr = readl(CCSR);
363 	unsigned int n2 = (ccsr & CCSR_N2_MASK) >> CCSR_N2_SHIFT;
364 
365 	return (parent_rate / n2) * 2;
366 }
367 PARENTS(clk_pxa27x_run) = { "cpll" };
368 RATE_RO_OPS(clk_pxa27x_run, "run");
369 
370 static void __init pxa27x_register_core(void)
371 {
372 	clkdev_pxa_register(CLK_NONE, "cpll", NULL,
373 			    clk_register_clk_pxa27x_cpll());
374 	clkdev_pxa_register(CLK_NONE, "run", NULL,
375 			    clk_register_clk_pxa27x_run());
376 	clkdev_pxa_register(CLK_CORE, "core", NULL,
377 			    clk_register_clk_pxa27x_core());
378 }
379 
380 static unsigned long clk_pxa27x_system_bus_get_rate(struct clk_hw *hw,
381 						    unsigned long parent_rate)
382 {
383 	unsigned long clkcfg;
384 	unsigned int b, osc_forced;
385 	unsigned long ccsr = readl(CCSR);
386 
387 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
388 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
389 	b  = clkcfg & (1 << 3);
390 
391 	if (osc_forced)
392 		return parent_rate;
393 	if (b)
394 		return parent_rate;
395 	else
396 		return parent_rate / 2;
397 }
398 
399 static u8 clk_pxa27x_system_bus_get_parent(struct clk_hw *hw)
400 {
401 	unsigned int osc_forced;
402 	unsigned long ccsr = readl(CCSR);
403 
404 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
405 	if (osc_forced)
406 		return PXA_BUS_13Mhz;
407 	else
408 		return PXA_BUS_RUN;
409 }
410 
411 PARENTS(clk_pxa27x_system_bus) = { "osc_13mhz", "run" };
412 MUX_RO_RATE_RO_OPS(clk_pxa27x_system_bus, "system_bus");
413 
414 static unsigned long clk_pxa27x_memory_get_rate(struct clk_hw *hw,
415 						unsigned long parent_rate)
416 {
417 	unsigned int a, l, osc_forced;
418 	unsigned long cccr = readl(CCCR);
419 	unsigned long ccsr = readl(CCSR);
420 
421 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
422 	a = cccr & (1 << CCCR_A_BIT);
423 	l  = ccsr & CCSR_L_MASK;
424 
425 	if (osc_forced || a)
426 		return parent_rate;
427 	if (l <= 10)
428 		return parent_rate;
429 	if (l <= 20)
430 		return parent_rate / 2;
431 	return parent_rate / 4;
432 }
433 
434 static u8 clk_pxa27x_memory_get_parent(struct clk_hw *hw)
435 {
436 	unsigned int osc_forced, a;
437 	unsigned long cccr = readl(CCCR);
438 	unsigned long ccsr = readl(CCSR);
439 
440 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
441 	a = cccr & (1 << CCCR_A_BIT);
442 	if (osc_forced)
443 		return PXA_MEM_13Mhz;
444 	if (a)
445 		return PXA_MEM_SYSTEM_BUS;
446 	else
447 		return PXA_MEM_RUN;
448 }
449 
450 PARENTS(clk_pxa27x_memory) = { "osc_13mhz", "system_bus", "run" };
451 MUX_RO_RATE_RO_OPS(clk_pxa27x_memory, "memory");
452 
453 #define DUMMY_CLK(_con_id, _dev_id, _parent) \
454 	{ .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
455 struct dummy_clk {
456 	const char *con_id;
457 	const char *dev_id;
458 	const char *parent;
459 };
460 static struct dummy_clk dummy_clks[] __initdata = {
461 	DUMMY_CLK(NULL, "pxa27x-gpio", "osc_32_768khz"),
462 	DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
463 	DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
464 };
465 
466 static void __init pxa27x_dummy_clocks_init(void)
467 {
468 	struct clk *clk;
469 	struct dummy_clk *d;
470 	const char *name;
471 	int i;
472 
473 	for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
474 		d = &dummy_clks[i];
475 		name = d->dev_id ? d->dev_id : d->con_id;
476 		clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
477 		clk_register_clkdev(clk, d->con_id, d->dev_id);
478 	}
479 }
480 
481 static void __init pxa27x_base_clocks_init(void)
482 {
483 	pxa27x_register_plls();
484 	pxa27x_register_core();
485 	clkdev_pxa_register(CLK_NONE, "system_bus", NULL,
486 			    clk_register_clk_pxa27x_system_bus());
487 	clkdev_pxa_register(CLK_NONE, "memory", NULL,
488 			    clk_register_clk_pxa27x_memory());
489 	clk_register_clk_pxa27x_lcd_base();
490 }
491 
492 int __init pxa27x_clocks_init(void)
493 {
494 	pxa27x_base_clocks_init();
495 	pxa27x_dummy_clocks_init();
496 	return clk_pxa_cken_init(pxa27x_clocks, ARRAY_SIZE(pxa27x_clocks));
497 }
498 
499 static void __init pxa27x_dt_clocks_init(struct device_node *np)
500 {
501 	pxa27x_clocks_init();
502 	clk_pxa_dt_common_init(np);
503 }
504 CLK_OF_DECLARE(pxa_clks, "marvell,pxa270-clocks", pxa27x_dt_clocks_init);
505