Merge tag 'drm-misc-fixes-2019-06-05' of git://anongit.freedesktop.org/drm/drm-misc...
[sfrench/cifs-2.6.git] / arch / arm / mach-ep93xx / clock.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * arch/arm/mach-ep93xx/clock.c
4  * Clock control for Cirrus EP93xx chips.
5  *
6  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
7  */
8
9 #define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
10
11 #include <linux/kernel.h>
12 #include <linux/clk.h>
13 #include <linux/err.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include <linux/io.h>
17 #include <linux/spinlock.h>
18 #include <linux/clkdev.h>
19 #include <linux/soc/cirrus/ep93xx.h>
20
21 #include "hardware.h"
22
23 #include <asm/div64.h>
24
25 #include "soc.h"
26
27 struct clk {
28         struct clk      *parent;
29         unsigned long   rate;
30         int             users;
31         int             sw_locked;
32         void __iomem    *enable_reg;
33         u32             enable_mask;
34
35         unsigned long   (*get_rate)(struct clk *clk);
36         int             (*set_rate)(struct clk *clk, unsigned long rate);
37 };
38
39
40 static unsigned long get_uart_rate(struct clk *clk);
41
42 static int set_keytchclk_rate(struct clk *clk, unsigned long rate);
43 static int set_div_rate(struct clk *clk, unsigned long rate);
44 static int set_i2s_sclk_rate(struct clk *clk, unsigned long rate);
45 static int set_i2s_lrclk_rate(struct clk *clk, unsigned long rate);
46
47 static struct clk clk_xtali = {
48         .rate           = EP93XX_EXT_CLK_RATE,
49 };
50 static struct clk clk_uart1 = {
51         .parent         = &clk_xtali,
52         .sw_locked      = 1,
53         .enable_reg     = EP93XX_SYSCON_DEVCFG,
54         .enable_mask    = EP93XX_SYSCON_DEVCFG_U1EN,
55         .get_rate       = get_uart_rate,
56 };
57 static struct clk clk_uart2 = {
58         .parent         = &clk_xtali,
59         .sw_locked      = 1,
60         .enable_reg     = EP93XX_SYSCON_DEVCFG,
61         .enable_mask    = EP93XX_SYSCON_DEVCFG_U2EN,
62         .get_rate       = get_uart_rate,
63 };
64 static struct clk clk_uart3 = {
65         .parent         = &clk_xtali,
66         .sw_locked      = 1,
67         .enable_reg     = EP93XX_SYSCON_DEVCFG,
68         .enable_mask    = EP93XX_SYSCON_DEVCFG_U3EN,
69         .get_rate       = get_uart_rate,
70 };
71 static struct clk clk_pll1 = {
72         .parent         = &clk_xtali,
73 };
74 static struct clk clk_f = {
75         .parent         = &clk_pll1,
76 };
77 static struct clk clk_h = {
78         .parent         = &clk_pll1,
79 };
80 static struct clk clk_p = {
81         .parent         = &clk_pll1,
82 };
83 static struct clk clk_pll2 = {
84         .parent         = &clk_xtali,
85 };
86 static struct clk clk_usb_host = {
87         .parent         = &clk_pll2,
88         .enable_reg     = EP93XX_SYSCON_PWRCNT,
89         .enable_mask    = EP93XX_SYSCON_PWRCNT_USH_EN,
90 };
91 static struct clk clk_keypad = {
92         .parent         = &clk_xtali,
93         .sw_locked      = 1,
94         .enable_reg     = EP93XX_SYSCON_KEYTCHCLKDIV,
95         .enable_mask    = EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
96         .set_rate       = set_keytchclk_rate,
97 };
98 static struct clk clk_adc = {
99         .parent         = &clk_xtali,
100         .sw_locked      = 1,
101         .enable_reg     = EP93XX_SYSCON_KEYTCHCLKDIV,
102         .enable_mask    = EP93XX_SYSCON_KEYTCHCLKDIV_TSEN,
103         .set_rate       = set_keytchclk_rate,
104 };
105 static struct clk clk_spi = {
106         .parent         = &clk_xtali,
107         .rate           = EP93XX_EXT_CLK_RATE,
108 };
109 static struct clk clk_pwm = {
110         .parent         = &clk_xtali,
111         .rate           = EP93XX_EXT_CLK_RATE,
112 };
113
114 static struct clk clk_video = {
115         .sw_locked      = 1,
116         .enable_reg     = EP93XX_SYSCON_VIDCLKDIV,
117         .enable_mask    = EP93XX_SYSCON_CLKDIV_ENABLE,
118         .set_rate       = set_div_rate,
119 };
120
121 static struct clk clk_i2s_mclk = {
122         .sw_locked      = 1,
123         .enable_reg     = EP93XX_SYSCON_I2SCLKDIV,
124         .enable_mask    = EP93XX_SYSCON_CLKDIV_ENABLE,
125         .set_rate       = set_div_rate,
126 };
127
128 static struct clk clk_i2s_sclk = {
129         .sw_locked      = 1,
130         .parent         = &clk_i2s_mclk,
131         .enable_reg     = EP93XX_SYSCON_I2SCLKDIV,
132         .enable_mask    = EP93XX_SYSCON_I2SCLKDIV_SENA,
133         .set_rate       = set_i2s_sclk_rate,
134 };
135
136 static struct clk clk_i2s_lrclk = {
137         .sw_locked      = 1,
138         .parent         = &clk_i2s_sclk,
139         .enable_reg     = EP93XX_SYSCON_I2SCLKDIV,
140         .enable_mask    = EP93XX_SYSCON_I2SCLKDIV_SENA,
141         .set_rate       = set_i2s_lrclk_rate,
142 };
143
144 /* DMA Clocks */
145 static struct clk clk_m2p0 = {
146         .parent         = &clk_h,
147         .enable_reg     = EP93XX_SYSCON_PWRCNT,
148         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P0,
149 };
150 static struct clk clk_m2p1 = {
151         .parent         = &clk_h,
152         .enable_reg     = EP93XX_SYSCON_PWRCNT,
153         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P1,
154 };
155 static struct clk clk_m2p2 = {
156         .parent         = &clk_h,
157         .enable_reg     = EP93XX_SYSCON_PWRCNT,
158         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P2,
159 };
160 static struct clk clk_m2p3 = {
161         .parent         = &clk_h,
162         .enable_reg     = EP93XX_SYSCON_PWRCNT,
163         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P3,
164 };
165 static struct clk clk_m2p4 = {
166         .parent         = &clk_h,
167         .enable_reg     = EP93XX_SYSCON_PWRCNT,
168         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P4,
169 };
170 static struct clk clk_m2p5 = {
171         .parent         = &clk_h,
172         .enable_reg     = EP93XX_SYSCON_PWRCNT,
173         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P5,
174 };
175 static struct clk clk_m2p6 = {
176         .parent         = &clk_h,
177         .enable_reg     = EP93XX_SYSCON_PWRCNT,
178         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P6,
179 };
180 static struct clk clk_m2p7 = {
181         .parent         = &clk_h,
182         .enable_reg     = EP93XX_SYSCON_PWRCNT,
183         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P7,
184 };
185 static struct clk clk_m2p8 = {
186         .parent         = &clk_h,
187         .enable_reg     = EP93XX_SYSCON_PWRCNT,
188         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P8,
189 };
190 static struct clk clk_m2p9 = {
191         .parent         = &clk_h,
192         .enable_reg     = EP93XX_SYSCON_PWRCNT,
193         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2P9,
194 };
195 static struct clk clk_m2m0 = {
196         .parent         = &clk_h,
197         .enable_reg     = EP93XX_SYSCON_PWRCNT,
198         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2M0,
199 };
200 static struct clk clk_m2m1 = {
201         .parent         = &clk_h,
202         .enable_reg     = EP93XX_SYSCON_PWRCNT,
203         .enable_mask    = EP93XX_SYSCON_PWRCNT_DMA_M2M1,
204 };
205
206 #define INIT_CK(dev,con,ck)                                     \
207         { .dev_id = dev, .con_id = con, .clk = ck }
208
209 static struct clk_lookup clocks[] = {
210         INIT_CK(NULL,                   "xtali",        &clk_xtali),
211         INIT_CK("apb:uart1",            NULL,           &clk_uart1),
212         INIT_CK("apb:uart2",            NULL,           &clk_uart2),
213         INIT_CK("apb:uart3",            NULL,           &clk_uart3),
214         INIT_CK(NULL,                   "pll1",         &clk_pll1),
215         INIT_CK(NULL,                   "fclk",         &clk_f),
216         INIT_CK(NULL,                   "hclk",         &clk_h),
217         INIT_CK(NULL,                   "apb_pclk",     &clk_p),
218         INIT_CK(NULL,                   "pll2",         &clk_pll2),
219         INIT_CK("ohci-platform",        NULL,           &clk_usb_host),
220         INIT_CK("ep93xx-keypad",        NULL,           &clk_keypad),
221         INIT_CK("ep93xx-adc",           NULL,           &clk_adc),
222         INIT_CK("ep93xx-fb",            NULL,           &clk_video),
223         INIT_CK("ep93xx-spi.0",         NULL,           &clk_spi),
224         INIT_CK("ep93xx-i2s",           "mclk",         &clk_i2s_mclk),
225         INIT_CK("ep93xx-i2s",           "sclk",         &clk_i2s_sclk),
226         INIT_CK("ep93xx-i2s",           "lrclk",        &clk_i2s_lrclk),
227         INIT_CK(NULL,                   "pwm_clk",      &clk_pwm),
228         INIT_CK(NULL,                   "m2p0",         &clk_m2p0),
229         INIT_CK(NULL,                   "m2p1",         &clk_m2p1),
230         INIT_CK(NULL,                   "m2p2",         &clk_m2p2),
231         INIT_CK(NULL,                   "m2p3",         &clk_m2p3),
232         INIT_CK(NULL,                   "m2p4",         &clk_m2p4),
233         INIT_CK(NULL,                   "m2p5",         &clk_m2p5),
234         INIT_CK(NULL,                   "m2p6",         &clk_m2p6),
235         INIT_CK(NULL,                   "m2p7",         &clk_m2p7),
236         INIT_CK(NULL,                   "m2p8",         &clk_m2p8),
237         INIT_CK(NULL,                   "m2p9",         &clk_m2p9),
238         INIT_CK(NULL,                   "m2m0",         &clk_m2m0),
239         INIT_CK(NULL,                   "m2m1",         &clk_m2m1),
240 };
241
242 static DEFINE_SPINLOCK(clk_lock);
243
244 static void __clk_enable(struct clk *clk)
245 {
246         if (!clk->users++) {
247                 if (clk->parent)
248                         __clk_enable(clk->parent);
249
250                 if (clk->enable_reg) {
251                         u32 v;
252
253                         v = __raw_readl(clk->enable_reg);
254                         v |= clk->enable_mask;
255                         if (clk->sw_locked)
256                                 ep93xx_syscon_swlocked_write(v, clk->enable_reg);
257                         else
258                                 __raw_writel(v, clk->enable_reg);
259                 }
260         }
261 }
262
263 int clk_enable(struct clk *clk)
264 {
265         unsigned long flags;
266
267         if (!clk)
268                 return -EINVAL;
269
270         spin_lock_irqsave(&clk_lock, flags);
271         __clk_enable(clk);
272         spin_unlock_irqrestore(&clk_lock, flags);
273
274         return 0;
275 }
276 EXPORT_SYMBOL(clk_enable);
277
278 static void __clk_disable(struct clk *clk)
279 {
280         if (!--clk->users) {
281                 if (clk->enable_reg) {
282                         u32 v;
283
284                         v = __raw_readl(clk->enable_reg);
285                         v &= ~clk->enable_mask;
286                         if (clk->sw_locked)
287                                 ep93xx_syscon_swlocked_write(v, clk->enable_reg);
288                         else
289                                 __raw_writel(v, clk->enable_reg);
290                 }
291
292                 if (clk->parent)
293                         __clk_disable(clk->parent);
294         }
295 }
296
297 void clk_disable(struct clk *clk)
298 {
299         unsigned long flags;
300
301         if (!clk)
302                 return;
303
304         spin_lock_irqsave(&clk_lock, flags);
305         __clk_disable(clk);
306         spin_unlock_irqrestore(&clk_lock, flags);
307 }
308 EXPORT_SYMBOL(clk_disable);
309
310 static unsigned long get_uart_rate(struct clk *clk)
311 {
312         unsigned long rate = clk_get_rate(clk->parent);
313         u32 value;
314
315         value = __raw_readl(EP93XX_SYSCON_PWRCNT);
316         if (value & EP93XX_SYSCON_PWRCNT_UARTBAUD)
317                 return rate;
318         else
319                 return rate / 2;
320 }
321
322 unsigned long clk_get_rate(struct clk *clk)
323 {
324         if (clk->get_rate)
325                 return clk->get_rate(clk);
326
327         return clk->rate;
328 }
329 EXPORT_SYMBOL(clk_get_rate);
330
331 static int set_keytchclk_rate(struct clk *clk, unsigned long rate)
332 {
333         u32 val;
334         u32 div_bit;
335
336         val = __raw_readl(clk->enable_reg);
337
338         /*
339          * The Key Matrix and ADC clocks are configured using the same
340          * System Controller register.  The clock used will be either
341          * 1/4 or 1/16 the external clock rate depending on the
342          * EP93XX_SYSCON_KEYTCHCLKDIV_KDIV/EP93XX_SYSCON_KEYTCHCLKDIV_ADIV
343          * bit being set or cleared.
344          */
345         div_bit = clk->enable_mask >> 15;
346
347         if (rate == EP93XX_KEYTCHCLK_DIV4)
348                 val |= div_bit;
349         else if (rate == EP93XX_KEYTCHCLK_DIV16)
350                 val &= ~div_bit;
351         else
352                 return -EINVAL;
353
354         ep93xx_syscon_swlocked_write(val, clk->enable_reg);
355         clk->rate = rate;
356         return 0;
357 }
358
359 static int calc_clk_div(struct clk *clk, unsigned long rate,
360                         int *psel, int *esel, int *pdiv, int *div)
361 {
362         struct clk *mclk;
363         unsigned long max_rate, actual_rate, mclk_rate, rate_err = -1;
364         int i, found = 0, __div = 0, __pdiv = 0;
365
366         /* Don't exceed the maximum rate */
367         max_rate = max3(clk_pll1.rate / 4, clk_pll2.rate / 4, clk_xtali.rate / 4);
368         rate = min(rate, max_rate);
369
370         /*
371          * Try the two pll's and the external clock
372          * Because the valid predividers are 2, 2.5 and 3, we multiply
373          * all the clocks by 2 to avoid floating point math.
374          *
375          * This is based on the algorithm in the ep93xx raster guide:
376          * http://be-a-maverick.com/en/pubs/appNote/AN269REV1.pdf
377          *
378          */
379         for (i = 0; i < 3; i++) {
380                 if (i == 0)
381                         mclk = &clk_xtali;
382                 else if (i == 1)
383                         mclk = &clk_pll1;
384                 else
385                         mclk = &clk_pll2;
386                 mclk_rate = mclk->rate * 2;
387
388                 /* Try each predivider value */
389                 for (__pdiv = 4; __pdiv <= 6; __pdiv++) {
390                         __div = mclk_rate / (rate * __pdiv);
391                         if (__div < 2 || __div > 127)
392                                 continue;
393
394                         actual_rate = mclk_rate / (__pdiv * __div);
395
396                         if (!found || abs(actual_rate - rate) < rate_err) {
397                                 *pdiv = __pdiv - 3;
398                                 *div = __div;
399                                 *psel = (i == 2);
400                                 *esel = (i != 0);
401                                 clk->parent = mclk;
402                                 clk->rate = actual_rate;
403                                 rate_err = abs(actual_rate - rate);
404                                 found = 1;
405                         }
406                 }
407         }
408
409         if (!found)
410                 return -EINVAL;
411
412         return 0;
413 }
414
415 static int set_div_rate(struct clk *clk, unsigned long rate)
416 {
417         int err, psel = 0, esel = 0, pdiv = 0, div = 0;
418         u32 val;
419
420         err = calc_clk_div(clk, rate, &psel, &esel, &pdiv, &div);
421         if (err)
422                 return err;
423
424         /* Clear the esel, psel, pdiv and div bits */
425         val = __raw_readl(clk->enable_reg);
426         val &= ~0x7fff;
427
428         /* Set the new esel, psel, pdiv and div bits for the new clock rate */
429         val |= (esel ? EP93XX_SYSCON_CLKDIV_ESEL : 0) |
430                 (psel ? EP93XX_SYSCON_CLKDIV_PSEL : 0) |
431                 (pdiv << EP93XX_SYSCON_CLKDIV_PDIV_SHIFT) | div;
432         ep93xx_syscon_swlocked_write(val, clk->enable_reg);
433         return 0;
434 }
435
436 static int set_i2s_sclk_rate(struct clk *clk, unsigned long rate)
437 {
438         unsigned val = __raw_readl(clk->enable_reg);
439
440         if (rate == clk_i2s_mclk.rate / 2)
441                 ep93xx_syscon_swlocked_write(val & ~EP93XX_I2SCLKDIV_SDIV, 
442                                              clk->enable_reg);
443         else if (rate == clk_i2s_mclk.rate / 4)
444                 ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_SDIV, 
445                                              clk->enable_reg);
446         else
447                 return -EINVAL;
448
449         clk_i2s_sclk.rate = rate;
450         return 0;
451 }
452
453 static int set_i2s_lrclk_rate(struct clk *clk, unsigned long rate)
454 {
455         unsigned val = __raw_readl(clk->enable_reg) & 
456                 ~EP93XX_I2SCLKDIV_LRDIV_MASK;
457         
458         if (rate == clk_i2s_sclk.rate / 32)
459                 ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_LRDIV32,
460                                              clk->enable_reg);
461         else if (rate == clk_i2s_sclk.rate / 64)
462                 ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_LRDIV64,
463                                              clk->enable_reg);
464         else if (rate == clk_i2s_sclk.rate / 128)
465                 ep93xx_syscon_swlocked_write(val | EP93XX_I2SCLKDIV_LRDIV128,
466                                              clk->enable_reg);
467         else
468                 return -EINVAL;
469
470         clk_i2s_lrclk.rate = rate;
471         return 0;
472 }
473
474 int clk_set_rate(struct clk *clk, unsigned long rate)
475 {
476         if (clk->set_rate)
477                 return clk->set_rate(clk, rate);
478
479         return -EINVAL;
480 }
481 EXPORT_SYMBOL(clk_set_rate);
482
483 long clk_round_rate(struct clk *clk, unsigned long rate)
484 {
485         WARN_ON(clk);
486         return 0;
487 }
488 EXPORT_SYMBOL(clk_round_rate);
489
490 int clk_set_parent(struct clk *clk, struct clk *parent)
491 {
492         WARN_ON(clk);
493         return 0;
494 }
495 EXPORT_SYMBOL(clk_set_parent);
496
497 struct clk *clk_get_parent(struct clk *clk)
498 {
499         return clk->parent;
500 }
501 EXPORT_SYMBOL(clk_get_parent);
502
503
504 static char fclk_divisors[] = { 1, 2, 4, 8, 16, 1, 1, 1 };
505 static char hclk_divisors[] = { 1, 2, 4, 5, 6, 8, 16, 32 };
506 static char pclk_divisors[] = { 1, 2, 4, 8 };
507
508 /*
509  * PLL rate = 14.7456 MHz * (X1FBD + 1) * (X2FBD + 1) / (X2IPD + 1) / 2^PS
510  */
511 static unsigned long calc_pll_rate(u32 config_word)
512 {
513         unsigned long long rate;
514         int i;
515
516         rate = clk_xtali.rate;
517         rate *= ((config_word >> 11) & 0x1f) + 1;               /* X1FBD */
518         rate *= ((config_word >> 5) & 0x3f) + 1;                /* X2FBD */
519         do_div(rate, (config_word & 0x1f) + 1);                 /* X2IPD */
520         for (i = 0; i < ((config_word >> 16) & 3); i++)         /* PS */
521                 rate >>= 1;
522
523         return (unsigned long)rate;
524 }
525
526 static void __init ep93xx_dma_clock_init(void)
527 {
528         clk_m2p0.rate = clk_h.rate;
529         clk_m2p1.rate = clk_h.rate;
530         clk_m2p2.rate = clk_h.rate;
531         clk_m2p3.rate = clk_h.rate;
532         clk_m2p4.rate = clk_h.rate;
533         clk_m2p5.rate = clk_h.rate;
534         clk_m2p6.rate = clk_h.rate;
535         clk_m2p7.rate = clk_h.rate;
536         clk_m2p8.rate = clk_h.rate;
537         clk_m2p9.rate = clk_h.rate;
538         clk_m2m0.rate = clk_h.rate;
539         clk_m2m1.rate = clk_h.rate;
540 }
541
542 static int __init ep93xx_clock_init(void)
543 {
544         u32 value;
545
546         /* Determine the bootloader configured pll1 rate */
547         value = __raw_readl(EP93XX_SYSCON_CLKSET1);
548         if (!(value & EP93XX_SYSCON_CLKSET1_NBYP1))
549                 clk_pll1.rate = clk_xtali.rate;
550         else
551                 clk_pll1.rate = calc_pll_rate(value);
552
553         /* Initialize the pll1 derived clocks */
554         clk_f.rate = clk_pll1.rate / fclk_divisors[(value >> 25) & 0x7];
555         clk_h.rate = clk_pll1.rate / hclk_divisors[(value >> 20) & 0x7];
556         clk_p.rate = clk_h.rate / pclk_divisors[(value >> 18) & 0x3];
557         ep93xx_dma_clock_init();
558
559         /* Determine the bootloader configured pll2 rate */
560         value = __raw_readl(EP93XX_SYSCON_CLKSET2);
561         if (!(value & EP93XX_SYSCON_CLKSET2_NBYP2))
562                 clk_pll2.rate = clk_xtali.rate;
563         else if (value & EP93XX_SYSCON_CLKSET2_PLL2_EN)
564                 clk_pll2.rate = calc_pll_rate(value);
565         else
566                 clk_pll2.rate = 0;
567
568         /* Initialize the pll2 derived clocks */
569         clk_usb_host.rate = clk_pll2.rate / (((value >> 28) & 0xf) + 1);
570
571         /*
572          * EP93xx SSP clock rate was doubled in version E2. For more information
573          * see:
574          *     http://www.cirrus.com/en/pubs/appNote/AN273REV4.pdf
575          */
576         if (ep93xx_chip_revision() < EP93XX_CHIP_REV_E2)
577                 clk_spi.rate /= 2;
578
579         pr_info("PLL1 running at %ld MHz, PLL2 at %ld MHz\n",
580                 clk_pll1.rate / 1000000, clk_pll2.rate / 1000000);
581         pr_info("FCLK %ld MHz, HCLK %ld MHz, PCLK %ld MHz\n",
582                 clk_f.rate / 1000000, clk_h.rate / 1000000,
583                 clk_p.rate / 1000000);
584
585         clkdev_add_table(clocks, ARRAY_SIZE(clocks));
586         return 0;
587 }
588 postcore_initcall(ep93xx_clock_init);