xref: /linux/arch/mips/ath79/clock.c (revision 56d06fa29edd58c448766014afd833b7ff51247b)
1 /*
2  *  Atheros AR71XX/AR724X/AR913X common routines
3  *
4  *  Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com>
5  *  Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
6  *
7  *  Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP
8  *
9  *  This program is free software; you can redistribute it and/or modify it
10  *  under the terms of the GNU General Public License version 2 as published
11  *  by the Free Software Foundation.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/err.h>
18 #include <linux/clk.h>
19 #include <linux/clkdev.h>
20 #include <linux/clk-provider.h>
21 
22 #include <asm/div64.h>
23 
24 #include <asm/mach-ath79/ath79.h>
25 #include <asm/mach-ath79/ar71xx_regs.h>
26 #include "common.h"
27 
28 #define AR71XX_BASE_FREQ	40000000
29 #define AR724X_BASE_FREQ	40000000
30 
31 static struct clk *clks[3];
32 static struct clk_onecell_data clk_data = {
33 	.clks = clks,
34 	.clk_num = ARRAY_SIZE(clks),
35 };
36 
37 static struct clk *__init ath79_add_sys_clkdev(
38 	const char *id, unsigned long rate)
39 {
40 	struct clk *clk;
41 	int err;
42 
43 	clk = clk_register_fixed_rate(NULL, id, NULL, CLK_IS_ROOT, rate);
44 	if (!clk)
45 		panic("failed to allocate %s clock structure", id);
46 
47 	err = clk_register_clkdev(clk, id, NULL);
48 	if (err)
49 		panic("unable to register %s clock device", id);
50 
51 	return clk;
52 }
53 
54 static void __init ar71xx_clocks_init(void)
55 {
56 	unsigned long ref_rate;
57 	unsigned long cpu_rate;
58 	unsigned long ddr_rate;
59 	unsigned long ahb_rate;
60 	u32 pll;
61 	u32 freq;
62 	u32 div;
63 
64 	ref_rate = AR71XX_BASE_FREQ;
65 
66 	pll = ath79_pll_rr(AR71XX_PLL_REG_CPU_CONFIG);
67 
68 	div = ((pll >> AR71XX_PLL_FB_SHIFT) & AR71XX_PLL_FB_MASK) + 1;
69 	freq = div * ref_rate;
70 
71 	div = ((pll >> AR71XX_CPU_DIV_SHIFT) & AR71XX_CPU_DIV_MASK) + 1;
72 	cpu_rate = freq / div;
73 
74 	div = ((pll >> AR71XX_DDR_DIV_SHIFT) & AR71XX_DDR_DIV_MASK) + 1;
75 	ddr_rate = freq / div;
76 
77 	div = (((pll >> AR71XX_AHB_DIV_SHIFT) & AR71XX_AHB_DIV_MASK) + 1) * 2;
78 	ahb_rate = cpu_rate / div;
79 
80 	ath79_add_sys_clkdev("ref", ref_rate);
81 	clks[0] = ath79_add_sys_clkdev("cpu", cpu_rate);
82 	clks[1] = ath79_add_sys_clkdev("ddr", ddr_rate);
83 	clks[2] = ath79_add_sys_clkdev("ahb", ahb_rate);
84 
85 	clk_add_alias("wdt", NULL, "ahb", NULL);
86 	clk_add_alias("uart", NULL, "ahb", NULL);
87 }
88 
89 static void __init ar724x_clocks_init(void)
90 {
91 	unsigned long ref_rate;
92 	unsigned long cpu_rate;
93 	unsigned long ddr_rate;
94 	unsigned long ahb_rate;
95 	u32 pll;
96 	u32 freq;
97 	u32 div;
98 
99 	ref_rate = AR724X_BASE_FREQ;
100 	pll = ath79_pll_rr(AR724X_PLL_REG_CPU_CONFIG);
101 
102 	div = ((pll >> AR724X_PLL_FB_SHIFT) & AR724X_PLL_FB_MASK);
103 	freq = div * ref_rate;
104 
105 	div = ((pll >> AR724X_PLL_REF_DIV_SHIFT) & AR724X_PLL_REF_DIV_MASK) * 2;
106 	freq /= div;
107 
108 	cpu_rate = freq;
109 
110 	div = ((pll >> AR724X_DDR_DIV_SHIFT) & AR724X_DDR_DIV_MASK) + 1;
111 	ddr_rate = freq / div;
112 
113 	div = (((pll >> AR724X_AHB_DIV_SHIFT) & AR724X_AHB_DIV_MASK) + 1) * 2;
114 	ahb_rate = cpu_rate / div;
115 
116 	ath79_add_sys_clkdev("ref", ref_rate);
117 	clks[0] = ath79_add_sys_clkdev("cpu", cpu_rate);
118 	clks[1] = ath79_add_sys_clkdev("ddr", ddr_rate);
119 	clks[2] = ath79_add_sys_clkdev("ahb", ahb_rate);
120 
121 	clk_add_alias("wdt", NULL, "ahb", NULL);
122 	clk_add_alias("uart", NULL, "ahb", NULL);
123 }
124 
125 static void __init ar933x_clocks_init(void)
126 {
127 	unsigned long ref_rate;
128 	unsigned long cpu_rate;
129 	unsigned long ddr_rate;
130 	unsigned long ahb_rate;
131 	u32 clock_ctrl;
132 	u32 cpu_config;
133 	u32 freq;
134 	u32 t;
135 
136 	t = ath79_reset_rr(AR933X_RESET_REG_BOOTSTRAP);
137 	if (t & AR933X_BOOTSTRAP_REF_CLK_40)
138 		ref_rate = (40 * 1000 * 1000);
139 	else
140 		ref_rate = (25 * 1000 * 1000);
141 
142 	clock_ctrl = ath79_pll_rr(AR933X_PLL_CLOCK_CTRL_REG);
143 	if (clock_ctrl & AR933X_PLL_CLOCK_CTRL_BYPASS) {
144 		cpu_rate = ref_rate;
145 		ahb_rate = ref_rate;
146 		ddr_rate = ref_rate;
147 	} else {
148 		cpu_config = ath79_pll_rr(AR933X_PLL_CPU_CONFIG_REG);
149 
150 		t = (cpu_config >> AR933X_PLL_CPU_CONFIG_REFDIV_SHIFT) &
151 		    AR933X_PLL_CPU_CONFIG_REFDIV_MASK;
152 		freq = ref_rate / t;
153 
154 		t = (cpu_config >> AR933X_PLL_CPU_CONFIG_NINT_SHIFT) &
155 		    AR933X_PLL_CPU_CONFIG_NINT_MASK;
156 		freq *= t;
157 
158 		t = (cpu_config >> AR933X_PLL_CPU_CONFIG_OUTDIV_SHIFT) &
159 		    AR933X_PLL_CPU_CONFIG_OUTDIV_MASK;
160 		if (t == 0)
161 			t = 1;
162 
163 		freq >>= t;
164 
165 		t = ((clock_ctrl >> AR933X_PLL_CLOCK_CTRL_CPU_DIV_SHIFT) &
166 		     AR933X_PLL_CLOCK_CTRL_CPU_DIV_MASK) + 1;
167 		cpu_rate = freq / t;
168 
169 		t = ((clock_ctrl >> AR933X_PLL_CLOCK_CTRL_DDR_DIV_SHIFT) &
170 		      AR933X_PLL_CLOCK_CTRL_DDR_DIV_MASK) + 1;
171 		ddr_rate = freq / t;
172 
173 		t = ((clock_ctrl >> AR933X_PLL_CLOCK_CTRL_AHB_DIV_SHIFT) &
174 		     AR933X_PLL_CLOCK_CTRL_AHB_DIV_MASK) + 1;
175 		ahb_rate = freq / t;
176 	}
177 
178 	ath79_add_sys_clkdev("ref", ref_rate);
179 	clks[0] = ath79_add_sys_clkdev("cpu", cpu_rate);
180 	clks[1] = ath79_add_sys_clkdev("ddr", ddr_rate);
181 	clks[2] = ath79_add_sys_clkdev("ahb", ahb_rate);
182 
183 	clk_add_alias("wdt", NULL, "ahb", NULL);
184 	clk_add_alias("uart", NULL, "ref", NULL);
185 }
186 
187 static u32 __init ar934x_get_pll_freq(u32 ref, u32 ref_div, u32 nint, u32 nfrac,
188 				      u32 frac, u32 out_div)
189 {
190 	u64 t;
191 	u32 ret;
192 
193 	t = ref;
194 	t *= nint;
195 	do_div(t, ref_div);
196 	ret = t;
197 
198 	t = ref;
199 	t *= nfrac;
200 	do_div(t, ref_div * frac);
201 	ret += t;
202 
203 	ret /= (1 << out_div);
204 	return ret;
205 }
206 
207 static void __init ar934x_clocks_init(void)
208 {
209 	unsigned long ref_rate;
210 	unsigned long cpu_rate;
211 	unsigned long ddr_rate;
212 	unsigned long ahb_rate;
213 	u32 pll, out_div, ref_div, nint, nfrac, frac, clk_ctrl, postdiv;
214 	u32 cpu_pll, ddr_pll;
215 	u32 bootstrap;
216 	void __iomem *dpll_base;
217 
218 	dpll_base = ioremap(AR934X_SRIF_BASE, AR934X_SRIF_SIZE);
219 
220 	bootstrap = ath79_reset_rr(AR934X_RESET_REG_BOOTSTRAP);
221 	if (bootstrap & AR934X_BOOTSTRAP_REF_CLK_40)
222 		ref_rate = 40 * 1000 * 1000;
223 	else
224 		ref_rate = 25 * 1000 * 1000;
225 
226 	pll = __raw_readl(dpll_base + AR934X_SRIF_CPU_DPLL2_REG);
227 	if (pll & AR934X_SRIF_DPLL2_LOCAL_PLL) {
228 		out_div = (pll >> AR934X_SRIF_DPLL2_OUTDIV_SHIFT) &
229 			  AR934X_SRIF_DPLL2_OUTDIV_MASK;
230 		pll = __raw_readl(dpll_base + AR934X_SRIF_CPU_DPLL1_REG);
231 		nint = (pll >> AR934X_SRIF_DPLL1_NINT_SHIFT) &
232 		       AR934X_SRIF_DPLL1_NINT_MASK;
233 		nfrac = pll & AR934X_SRIF_DPLL1_NFRAC_MASK;
234 		ref_div = (pll >> AR934X_SRIF_DPLL1_REFDIV_SHIFT) &
235 			  AR934X_SRIF_DPLL1_REFDIV_MASK;
236 		frac = 1 << 18;
237 	} else {
238 		pll = ath79_pll_rr(AR934X_PLL_CPU_CONFIG_REG);
239 		out_div = (pll >> AR934X_PLL_CPU_CONFIG_OUTDIV_SHIFT) &
240 			AR934X_PLL_CPU_CONFIG_OUTDIV_MASK;
241 		ref_div = (pll >> AR934X_PLL_CPU_CONFIG_REFDIV_SHIFT) &
242 			  AR934X_PLL_CPU_CONFIG_REFDIV_MASK;
243 		nint = (pll >> AR934X_PLL_CPU_CONFIG_NINT_SHIFT) &
244 		       AR934X_PLL_CPU_CONFIG_NINT_MASK;
245 		nfrac = (pll >> AR934X_PLL_CPU_CONFIG_NFRAC_SHIFT) &
246 			AR934X_PLL_CPU_CONFIG_NFRAC_MASK;
247 		frac = 1 << 6;
248 	}
249 
250 	cpu_pll = ar934x_get_pll_freq(ref_rate, ref_div, nint,
251 				      nfrac, frac, out_div);
252 
253 	pll = __raw_readl(dpll_base + AR934X_SRIF_DDR_DPLL2_REG);
254 	if (pll & AR934X_SRIF_DPLL2_LOCAL_PLL) {
255 		out_div = (pll >> AR934X_SRIF_DPLL2_OUTDIV_SHIFT) &
256 			  AR934X_SRIF_DPLL2_OUTDIV_MASK;
257 		pll = __raw_readl(dpll_base + AR934X_SRIF_DDR_DPLL1_REG);
258 		nint = (pll >> AR934X_SRIF_DPLL1_NINT_SHIFT) &
259 		       AR934X_SRIF_DPLL1_NINT_MASK;
260 		nfrac = pll & AR934X_SRIF_DPLL1_NFRAC_MASK;
261 		ref_div = (pll >> AR934X_SRIF_DPLL1_REFDIV_SHIFT) &
262 			  AR934X_SRIF_DPLL1_REFDIV_MASK;
263 		frac = 1 << 18;
264 	} else {
265 		pll = ath79_pll_rr(AR934X_PLL_DDR_CONFIG_REG);
266 		out_div = (pll >> AR934X_PLL_DDR_CONFIG_OUTDIV_SHIFT) &
267 			  AR934X_PLL_DDR_CONFIG_OUTDIV_MASK;
268 		ref_div = (pll >> AR934X_PLL_DDR_CONFIG_REFDIV_SHIFT) &
269 			   AR934X_PLL_DDR_CONFIG_REFDIV_MASK;
270 		nint = (pll >> AR934X_PLL_DDR_CONFIG_NINT_SHIFT) &
271 		       AR934X_PLL_DDR_CONFIG_NINT_MASK;
272 		nfrac = (pll >> AR934X_PLL_DDR_CONFIG_NFRAC_SHIFT) &
273 			AR934X_PLL_DDR_CONFIG_NFRAC_MASK;
274 		frac = 1 << 10;
275 	}
276 
277 	ddr_pll = ar934x_get_pll_freq(ref_rate, ref_div, nint,
278 				      nfrac, frac, out_div);
279 
280 	clk_ctrl = ath79_pll_rr(AR934X_PLL_CPU_DDR_CLK_CTRL_REG);
281 
282 	postdiv = (clk_ctrl >> AR934X_PLL_CPU_DDR_CLK_CTRL_CPU_POST_DIV_SHIFT) &
283 		  AR934X_PLL_CPU_DDR_CLK_CTRL_CPU_POST_DIV_MASK;
284 
285 	if (clk_ctrl & AR934X_PLL_CPU_DDR_CLK_CTRL_CPU_PLL_BYPASS)
286 		cpu_rate = ref_rate;
287 	else if (clk_ctrl & AR934X_PLL_CPU_DDR_CLK_CTRL_CPUCLK_FROM_CPUPLL)
288 		cpu_rate = cpu_pll / (postdiv + 1);
289 	else
290 		cpu_rate = ddr_pll / (postdiv + 1);
291 
292 	postdiv = (clk_ctrl >> AR934X_PLL_CPU_DDR_CLK_CTRL_DDR_POST_DIV_SHIFT) &
293 		  AR934X_PLL_CPU_DDR_CLK_CTRL_DDR_POST_DIV_MASK;
294 
295 	if (clk_ctrl & AR934X_PLL_CPU_DDR_CLK_CTRL_DDR_PLL_BYPASS)
296 		ddr_rate = ref_rate;
297 	else if (clk_ctrl & AR934X_PLL_CPU_DDR_CLK_CTRL_DDRCLK_FROM_DDRPLL)
298 		ddr_rate = ddr_pll / (postdiv + 1);
299 	else
300 		ddr_rate = cpu_pll / (postdiv + 1);
301 
302 	postdiv = (clk_ctrl >> AR934X_PLL_CPU_DDR_CLK_CTRL_AHB_POST_DIV_SHIFT) &
303 		  AR934X_PLL_CPU_DDR_CLK_CTRL_AHB_POST_DIV_MASK;
304 
305 	if (clk_ctrl & AR934X_PLL_CPU_DDR_CLK_CTRL_AHB_PLL_BYPASS)
306 		ahb_rate = ref_rate;
307 	else if (clk_ctrl & AR934X_PLL_CPU_DDR_CLK_CTRL_AHBCLK_FROM_DDRPLL)
308 		ahb_rate = ddr_pll / (postdiv + 1);
309 	else
310 		ahb_rate = cpu_pll / (postdiv + 1);
311 
312 	ath79_add_sys_clkdev("ref", ref_rate);
313 	clks[0] = ath79_add_sys_clkdev("cpu", cpu_rate);
314 	clks[1] = ath79_add_sys_clkdev("ddr", ddr_rate);
315 	clks[2] = ath79_add_sys_clkdev("ahb", ahb_rate);
316 
317 	clk_add_alias("wdt", NULL, "ref", NULL);
318 	clk_add_alias("uart", NULL, "ref", NULL);
319 
320 	iounmap(dpll_base);
321 }
322 
323 static void __init qca955x_clocks_init(void)
324 {
325 	unsigned long ref_rate;
326 	unsigned long cpu_rate;
327 	unsigned long ddr_rate;
328 	unsigned long ahb_rate;
329 	u32 pll, out_div, ref_div, nint, frac, clk_ctrl, postdiv;
330 	u32 cpu_pll, ddr_pll;
331 	u32 bootstrap;
332 
333 	bootstrap = ath79_reset_rr(QCA955X_RESET_REG_BOOTSTRAP);
334 	if (bootstrap &	QCA955X_BOOTSTRAP_REF_CLK_40)
335 		ref_rate = 40 * 1000 * 1000;
336 	else
337 		ref_rate = 25 * 1000 * 1000;
338 
339 	pll = ath79_pll_rr(QCA955X_PLL_CPU_CONFIG_REG);
340 	out_div = (pll >> QCA955X_PLL_CPU_CONFIG_OUTDIV_SHIFT) &
341 		  QCA955X_PLL_CPU_CONFIG_OUTDIV_MASK;
342 	ref_div = (pll >> QCA955X_PLL_CPU_CONFIG_REFDIV_SHIFT) &
343 		  QCA955X_PLL_CPU_CONFIG_REFDIV_MASK;
344 	nint = (pll >> QCA955X_PLL_CPU_CONFIG_NINT_SHIFT) &
345 	       QCA955X_PLL_CPU_CONFIG_NINT_MASK;
346 	frac = (pll >> QCA955X_PLL_CPU_CONFIG_NFRAC_SHIFT) &
347 	       QCA955X_PLL_CPU_CONFIG_NFRAC_MASK;
348 
349 	cpu_pll = nint * ref_rate / ref_div;
350 	cpu_pll += frac * ref_rate / (ref_div * (1 << 6));
351 	cpu_pll /= (1 << out_div);
352 
353 	pll = ath79_pll_rr(QCA955X_PLL_DDR_CONFIG_REG);
354 	out_div = (pll >> QCA955X_PLL_DDR_CONFIG_OUTDIV_SHIFT) &
355 		  QCA955X_PLL_DDR_CONFIG_OUTDIV_MASK;
356 	ref_div = (pll >> QCA955X_PLL_DDR_CONFIG_REFDIV_SHIFT) &
357 		  QCA955X_PLL_DDR_CONFIG_REFDIV_MASK;
358 	nint = (pll >> QCA955X_PLL_DDR_CONFIG_NINT_SHIFT) &
359 	       QCA955X_PLL_DDR_CONFIG_NINT_MASK;
360 	frac = (pll >> QCA955X_PLL_DDR_CONFIG_NFRAC_SHIFT) &
361 	       QCA955X_PLL_DDR_CONFIG_NFRAC_MASK;
362 
363 	ddr_pll = nint * ref_rate / ref_div;
364 	ddr_pll += frac * ref_rate / (ref_div * (1 << 10));
365 	ddr_pll /= (1 << out_div);
366 
367 	clk_ctrl = ath79_pll_rr(QCA955X_PLL_CLK_CTRL_REG);
368 
369 	postdiv = (clk_ctrl >> QCA955X_PLL_CLK_CTRL_CPU_POST_DIV_SHIFT) &
370 		  QCA955X_PLL_CLK_CTRL_CPU_POST_DIV_MASK;
371 
372 	if (clk_ctrl & QCA955X_PLL_CLK_CTRL_CPU_PLL_BYPASS)
373 		cpu_rate = ref_rate;
374 	else if (clk_ctrl & QCA955X_PLL_CLK_CTRL_CPUCLK_FROM_CPUPLL)
375 		cpu_rate = ddr_pll / (postdiv + 1);
376 	else
377 		cpu_rate = cpu_pll / (postdiv + 1);
378 
379 	postdiv = (clk_ctrl >> QCA955X_PLL_CLK_CTRL_DDR_POST_DIV_SHIFT) &
380 		  QCA955X_PLL_CLK_CTRL_DDR_POST_DIV_MASK;
381 
382 	if (clk_ctrl & QCA955X_PLL_CLK_CTRL_DDR_PLL_BYPASS)
383 		ddr_rate = ref_rate;
384 	else if (clk_ctrl & QCA955X_PLL_CLK_CTRL_DDRCLK_FROM_DDRPLL)
385 		ddr_rate = cpu_pll / (postdiv + 1);
386 	else
387 		ddr_rate = ddr_pll / (postdiv + 1);
388 
389 	postdiv = (clk_ctrl >> QCA955X_PLL_CLK_CTRL_AHB_POST_DIV_SHIFT) &
390 		  QCA955X_PLL_CLK_CTRL_AHB_POST_DIV_MASK;
391 
392 	if (clk_ctrl & QCA955X_PLL_CLK_CTRL_AHB_PLL_BYPASS)
393 		ahb_rate = ref_rate;
394 	else if (clk_ctrl & QCA955X_PLL_CLK_CTRL_AHBCLK_FROM_DDRPLL)
395 		ahb_rate = ddr_pll / (postdiv + 1);
396 	else
397 		ahb_rate = cpu_pll / (postdiv + 1);
398 
399 	ath79_add_sys_clkdev("ref", ref_rate);
400 	clks[0] = ath79_add_sys_clkdev("cpu", cpu_rate);
401 	clks[1] = ath79_add_sys_clkdev("ddr", ddr_rate);
402 	clks[2] = ath79_add_sys_clkdev("ahb", ahb_rate);
403 
404 	clk_add_alias("wdt", NULL, "ref", NULL);
405 	clk_add_alias("uart", NULL, "ref", NULL);
406 }
407 
408 void __init ath79_clocks_init(void)
409 {
410 	if (soc_is_ar71xx())
411 		ar71xx_clocks_init();
412 	else if (soc_is_ar724x() || soc_is_ar913x())
413 		ar724x_clocks_init();
414 	else if (soc_is_ar933x())
415 		ar933x_clocks_init();
416 	else if (soc_is_ar934x())
417 		ar934x_clocks_init();
418 	else if (soc_is_qca955x())
419 		qca955x_clocks_init();
420 	else
421 		BUG();
422 
423 	of_clk_init(NULL);
424 }
425 
426 unsigned long __init
427 ath79_get_sys_clk_rate(const char *id)
428 {
429 	struct clk *clk;
430 	unsigned long rate;
431 
432 	clk = clk_get(NULL, id);
433 	if (IS_ERR(clk))
434 		panic("unable to get %s clock, err=%d", id, (int) PTR_ERR(clk));
435 
436 	rate = clk_get_rate(clk);
437 	clk_put(clk);
438 
439 	return rate;
440 }
441 
442 #ifdef CONFIG_OF
443 static void __init ath79_clocks_init_dt(struct device_node *np)
444 {
445 	of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
446 }
447 
448 CLK_OF_DECLARE(ar7100, "qca,ar7100-pll", ath79_clocks_init_dt);
449 CLK_OF_DECLARE(ar7240, "qca,ar7240-pll", ath79_clocks_init_dt);
450 CLK_OF_DECLARE(ar9130, "qca,ar9130-pll", ath79_clocks_init_dt);
451 CLK_OF_DECLARE(ar9330, "qca,ar9330-pll", ath79_clocks_init_dt);
452 CLK_OF_DECLARE(ar9340, "qca,ar9340-pll", ath79_clocks_init_dt);
453 CLK_OF_DECLARE(ar9550, "qca,qca9550-pll", ath79_clocks_init_dt);
454 #endif
455