OMAP1/2/3 clock: remove paranoid checks in preparation for clock{,2xxx,3xxx}_data.c
[linux-2.6-block.git] / arch / arm / mach-omap1 / clock.c
1 /*
2  *  linux/arch/arm/mach-omap1/clock.c
3  *
4  *  Copyright (C) 2004 - 2005 Nokia corporation
5  *  Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
6  *
7  *  Modified to use omap shared clock framework by
8  *  Tony Lindgren <tony@atomide.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/list.h>
17 #include <linux/errno.h>
18 #include <linux/err.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21
22 #include <asm/mach-types.h>
23 #include <asm/clkdev.h>
24
25 #include <plat/cpu.h>
26 #include <plat/usb.h>
27 #include <plat/clock.h>
28 #include <plat/sram.h>
29
30 static const struct clkops clkops_generic;
31 static const struct clkops clkops_uart;
32 static const struct clkops clkops_dspck;
33
34 #include "clock.h"
35
36 static int clk_omap1_dummy_enable(struct clk *clk)
37 {
38         return 0;
39 }
40
41 static void clk_omap1_dummy_disable(struct clk *clk)
42 {
43 }
44
45 static const struct clkops clkops_dummy = {
46         .enable = clk_omap1_dummy_enable,
47         .disable = clk_omap1_dummy_disable,
48 };
49
50 static struct clk dummy_ck = {
51         .name   = "dummy",
52         .ops    = &clkops_dummy,
53         .flags  = RATE_FIXED,
54 };
55
56 struct omap_clk {
57         u32             cpu;
58         struct clk_lookup lk;
59 };
60
61 #define CLK(dev, con, ck, cp)           \
62         {                               \
63                  .cpu = cp,             \
64                 .lk = {                 \
65                         .dev_id = dev,  \
66                         .con_id = con,  \
67                         .clk = ck,      \
68                 },                      \
69         }
70
71 #define CK_310  (1 << 0)
72 #define CK_7XX  (1 << 1)
73 #define CK_1510 (1 << 2)
74 #define CK_16XX (1 << 3)
75
76 static struct omap_clk omap_clks[] = {
77         /* non-ULPD clocks */
78         CLK(NULL,       "ck_ref",       &ck_ref,        CK_16XX | CK_1510 | CK_310 | CK_7XX),
79         CLK(NULL,       "ck_dpll1",     &ck_dpll1,      CK_16XX | CK_1510 | CK_310),
80         /* CK_GEN1 clocks */
81         CLK(NULL,       "ck_dpll1out",  &ck_dpll1out.clk, CK_16XX),
82         CLK(NULL,       "ck_sossi",     &sossi_ck,      CK_16XX),
83         CLK(NULL,       "arm_ck",       &arm_ck,        CK_16XX | CK_1510 | CK_310),
84         CLK(NULL,       "armper_ck",    &armper_ck.clk, CK_16XX | CK_1510 | CK_310),
85         CLK(NULL,       "arm_gpio_ck",  &arm_gpio_ck,   CK_1510 | CK_310),
86         CLK(NULL,       "armxor_ck",    &armxor_ck.clk, CK_16XX | CK_1510 | CK_310 | CK_7XX),
87         CLK(NULL,       "armtim_ck",    &armtim_ck.clk, CK_16XX | CK_1510 | CK_310),
88         CLK("omap_wdt", "fck",          &armwdt_ck.clk, CK_16XX | CK_1510 | CK_310),
89         CLK("omap_wdt", "ick",          &armper_ck.clk, CK_16XX),
90         CLK("omap_wdt", "ick",          &dummy_ck,      CK_1510 | CK_310),
91         CLK(NULL,       "arminth_ck",   &arminth_ck1510, CK_1510 | CK_310),
92         CLK(NULL,       "arminth_ck",   &arminth_ck16xx, CK_16XX),
93         /* CK_GEN2 clocks */
94         CLK(NULL,       "dsp_ck",       &dsp_ck,        CK_16XX | CK_1510 | CK_310),
95         CLK(NULL,       "dspmmu_ck",    &dspmmu_ck,     CK_16XX | CK_1510 | CK_310),
96         CLK(NULL,       "dspper_ck",    &dspper_ck,     CK_16XX | CK_1510 | CK_310),
97         CLK(NULL,       "dspxor_ck",    &dspxor_ck,     CK_16XX | CK_1510 | CK_310),
98         CLK(NULL,       "dsptim_ck",    &dsptim_ck,     CK_16XX | CK_1510 | CK_310),
99         /* CK_GEN3 clocks */
100         CLK(NULL,       "tc_ck",        &tc_ck.clk,     CK_16XX | CK_1510 | CK_310 | CK_7XX),
101         CLK(NULL,       "tipb_ck",      &tipb_ck,       CK_1510 | CK_310),
102         CLK(NULL,       "l3_ocpi_ck",   &l3_ocpi_ck,    CK_16XX | CK_7XX),
103         CLK(NULL,       "tc1_ck",       &tc1_ck,        CK_16XX),
104         CLK(NULL,       "tc2_ck",       &tc2_ck,        CK_16XX),
105         CLK(NULL,       "dma_ck",       &dma_ck,        CK_16XX | CK_1510 | CK_310),
106         CLK(NULL,       "dma_lcdfree_ck", &dma_lcdfree_ck, CK_16XX),
107         CLK(NULL,       "api_ck",       &api_ck.clk,    CK_16XX | CK_1510 | CK_310),
108         CLK(NULL,       "lb_ck",        &lb_ck.clk,     CK_1510 | CK_310),
109         CLK(NULL,       "rhea1_ck",     &rhea1_ck,      CK_16XX),
110         CLK(NULL,       "rhea2_ck",     &rhea2_ck,      CK_16XX),
111         CLK(NULL,       "lcd_ck",       &lcd_ck_16xx,   CK_16XX | CK_7XX),
112         CLK(NULL,       "lcd_ck",       &lcd_ck_1510.clk, CK_1510 | CK_310),
113         /* ULPD clocks */
114         CLK(NULL,       "uart1_ck",     &uart1_1510,    CK_1510 | CK_310),
115         CLK(NULL,       "uart1_ck",     &uart1_16xx.clk, CK_16XX),
116         CLK(NULL,       "uart2_ck",     &uart2_ck,      CK_16XX | CK_1510 | CK_310),
117         CLK(NULL,       "uart3_ck",     &uart3_1510,    CK_1510 | CK_310),
118         CLK(NULL,       "uart3_ck",     &uart3_16xx.clk, CK_16XX),
119         CLK(NULL,       "usb_clko",     &usb_clko,      CK_16XX | CK_1510 | CK_310),
120         CLK(NULL,       "usb_hhc_ck",   &usb_hhc_ck1510, CK_1510 | CK_310),
121         CLK(NULL,       "usb_hhc_ck",   &usb_hhc_ck16xx, CK_16XX),
122         CLK(NULL,       "usb_dc_ck",    &usb_dc_ck,     CK_16XX),
123         CLK(NULL,       "usb_dc_ck",    &usb_dc_ck7xx,  CK_7XX),
124         CLK(NULL,       "mclk",         &mclk_1510,     CK_1510 | CK_310),
125         CLK(NULL,       "mclk",         &mclk_16xx,     CK_16XX),
126         CLK(NULL,       "bclk",         &bclk_1510,     CK_1510 | CK_310),
127         CLK(NULL,       "bclk",         &bclk_16xx,     CK_16XX),
128         CLK("mmci-omap.0", "fck",       &mmc1_ck,       CK_16XX | CK_1510 | CK_310),
129         CLK("mmci-omap.0", "fck",       &mmc3_ck,       CK_7XX),
130         CLK("mmci-omap.0", "ick",       &armper_ck.clk, CK_16XX | CK_1510 | CK_310 | CK_7XX),
131         CLK("mmci-omap.1", "fck",       &mmc2_ck,       CK_16XX),
132         CLK("mmci-omap.1", "ick",       &armper_ck.clk, CK_16XX),
133         /* Virtual clocks */
134         CLK(NULL,       "mpu",          &virtual_ck_mpu, CK_16XX | CK_1510 | CK_310),
135         CLK("i2c_omap.1", "fck",        &i2c_fck,       CK_16XX | CK_1510 | CK_310),
136         CLK("i2c_omap.1", "ick",        &i2c_ick,       CK_16XX),
137         CLK("i2c_omap.1", "ick",        &dummy_ck,      CK_1510 | CK_310),
138         CLK("omap_uwire", "fck",        &armxor_ck.clk, CK_16XX | CK_1510 | CK_310),
139         CLK("omap-mcbsp.1", "ick",      &dspper_ck,     CK_16XX),
140         CLK("omap-mcbsp.1", "ick",      &dummy_ck,      CK_1510 | CK_310),
141         CLK("omap-mcbsp.2", "ick",      &armper_ck.clk, CK_16XX),
142         CLK("omap-mcbsp.2", "ick",      &dummy_ck,      CK_1510 | CK_310),
143         CLK("omap-mcbsp.3", "ick",      &dspper_ck,     CK_16XX),
144         CLK("omap-mcbsp.3", "ick",      &dummy_ck,      CK_1510 | CK_310),
145         CLK("omap-mcbsp.1", "fck",      &dspxor_ck,     CK_16XX | CK_1510 | CK_310),
146         CLK("omap-mcbsp.2", "fck",      &armper_ck.clk, CK_16XX | CK_1510 | CK_310),
147         CLK("omap-mcbsp.3", "fck",      &dspxor_ck,     CK_16XX | CK_1510 | CK_310),
148 };
149
150 static int omap1_clk_enable_generic(struct clk * clk);
151 static int omap1_clk_enable(struct clk *clk);
152 static void omap1_clk_disable_generic(struct clk * clk);
153 static void omap1_clk_disable(struct clk *clk);
154
155 __u32 arm_idlect1_mask;
156
157 /*-------------------------------------------------------------------------
158  * Omap1 specific clock functions
159  *-------------------------------------------------------------------------*/
160
161 static unsigned long omap1_watchdog_recalc(struct clk *clk)
162 {
163         return clk->parent->rate / 14;
164 }
165
166 static unsigned long omap1_uart_recalc(struct clk *clk)
167 {
168         unsigned int val = __raw_readl(clk->enable_reg);
169         return val & clk->enable_bit ? 48000000 : 12000000;
170 }
171
172 static unsigned long omap1_sossi_recalc(struct clk *clk)
173 {
174         u32 div = omap_readl(MOD_CONF_CTRL_1);
175
176         div = (div >> 17) & 0x7;
177         div++;
178
179         return clk->parent->rate / div;
180 }
181
182 static int omap1_clk_enable_dsp_domain(struct clk *clk)
183 {
184         int retval;
185
186         retval = omap1_clk_enable(&api_ck.clk);
187         if (!retval) {
188                 retval = omap1_clk_enable_generic(clk);
189                 omap1_clk_disable(&api_ck.clk);
190         }
191
192         return retval;
193 }
194
195 static void omap1_clk_disable_dsp_domain(struct clk *clk)
196 {
197         if (omap1_clk_enable(&api_ck.clk) == 0) {
198                 omap1_clk_disable_generic(clk);
199                 omap1_clk_disable(&api_ck.clk);
200         }
201 }
202
203 static const struct clkops clkops_dspck = {
204         .enable         = &omap1_clk_enable_dsp_domain,
205         .disable        = &omap1_clk_disable_dsp_domain,
206 };
207
208 static int omap1_clk_enable_uart_functional(struct clk *clk)
209 {
210         int ret;
211         struct uart_clk *uclk;
212
213         ret = omap1_clk_enable_generic(clk);
214         if (ret == 0) {
215                 /* Set smart idle acknowledgement mode */
216                 uclk = (struct uart_clk *)clk;
217                 omap_writeb((omap_readb(uclk->sysc_addr) & ~0x10) | 8,
218                             uclk->sysc_addr);
219         }
220
221         return ret;
222 }
223
224 static void omap1_clk_disable_uart_functional(struct clk *clk)
225 {
226         struct uart_clk *uclk;
227
228         /* Set force idle acknowledgement mode */
229         uclk = (struct uart_clk *)clk;
230         omap_writeb((omap_readb(uclk->sysc_addr) & ~0x18), uclk->sysc_addr);
231
232         omap1_clk_disable_generic(clk);
233 }
234
235 static const struct clkops clkops_uart = {
236         .enable         = &omap1_clk_enable_uart_functional,
237         .disable        = &omap1_clk_disable_uart_functional,
238 };
239
240 static void omap1_clk_allow_idle(struct clk *clk)
241 {
242         struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
243
244         if (!(clk->flags & CLOCK_IDLE_CONTROL))
245                 return;
246
247         if (iclk->no_idle_count > 0 && !(--iclk->no_idle_count))
248                 arm_idlect1_mask |= 1 << iclk->idlect_shift;
249 }
250
251 static void omap1_clk_deny_idle(struct clk *clk)
252 {
253         struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk;
254
255         if (!(clk->flags & CLOCK_IDLE_CONTROL))
256                 return;
257
258         if (iclk->no_idle_count++ == 0)
259                 arm_idlect1_mask &= ~(1 << iclk->idlect_shift);
260 }
261
262 static __u16 verify_ckctl_value(__u16 newval)
263 {
264         /* This function checks for following limitations set
265          * by the hardware (all conditions must be true):
266          * DSPMMU_CK == DSP_CK  or  DSPMMU_CK == DSP_CK/2
267          * ARM_CK >= TC_CK
268          * DSP_CK >= TC_CK
269          * DSPMMU_CK >= TC_CK
270          *
271          * In addition following rules are enforced:
272          * LCD_CK <= TC_CK
273          * ARMPER_CK <= TC_CK
274          *
275          * However, maximum frequencies are not checked for!
276          */
277         __u8 per_exp;
278         __u8 lcd_exp;
279         __u8 arm_exp;
280         __u8 dsp_exp;
281         __u8 tc_exp;
282         __u8 dspmmu_exp;
283
284         per_exp = (newval >> CKCTL_PERDIV_OFFSET) & 3;
285         lcd_exp = (newval >> CKCTL_LCDDIV_OFFSET) & 3;
286         arm_exp = (newval >> CKCTL_ARMDIV_OFFSET) & 3;
287         dsp_exp = (newval >> CKCTL_DSPDIV_OFFSET) & 3;
288         tc_exp = (newval >> CKCTL_TCDIV_OFFSET) & 3;
289         dspmmu_exp = (newval >> CKCTL_DSPMMUDIV_OFFSET) & 3;
290
291         if (dspmmu_exp < dsp_exp)
292                 dspmmu_exp = dsp_exp;
293         if (dspmmu_exp > dsp_exp+1)
294                 dspmmu_exp = dsp_exp+1;
295         if (tc_exp < arm_exp)
296                 tc_exp = arm_exp;
297         if (tc_exp < dspmmu_exp)
298                 tc_exp = dspmmu_exp;
299         if (tc_exp > lcd_exp)
300                 lcd_exp = tc_exp;
301         if (tc_exp > per_exp)
302                 per_exp = tc_exp;
303
304         newval &= 0xf000;
305         newval |= per_exp << CKCTL_PERDIV_OFFSET;
306         newval |= lcd_exp << CKCTL_LCDDIV_OFFSET;
307         newval |= arm_exp << CKCTL_ARMDIV_OFFSET;
308         newval |= dsp_exp << CKCTL_DSPDIV_OFFSET;
309         newval |= tc_exp << CKCTL_TCDIV_OFFSET;
310         newval |= dspmmu_exp << CKCTL_DSPMMUDIV_OFFSET;
311
312         return newval;
313 }
314
315 static int calc_dsor_exp(struct clk *clk, unsigned long rate)
316 {
317         /* Note: If target frequency is too low, this function will return 4,
318          * which is invalid value. Caller must check for this value and act
319          * accordingly.
320          *
321          * Note: This function does not check for following limitations set
322          * by the hardware (all conditions must be true):
323          * DSPMMU_CK == DSP_CK  or  DSPMMU_CK == DSP_CK/2
324          * ARM_CK >= TC_CK
325          * DSP_CK >= TC_CK
326          * DSPMMU_CK >= TC_CK
327          */
328         unsigned long realrate;
329         struct clk * parent;
330         unsigned  dsor_exp;
331
332         parent = clk->parent;
333         if (unlikely(parent == NULL))
334                 return -EIO;
335
336         realrate = parent->rate;
337         for (dsor_exp=0; dsor_exp<4; dsor_exp++) {
338                 if (realrate <= rate)
339                         break;
340
341                 realrate /= 2;
342         }
343
344         return dsor_exp;
345 }
346
347 static unsigned long omap1_ckctl_recalc(struct clk *clk)
348 {
349         /* Calculate divisor encoded as 2-bit exponent */
350         int dsor = 1 << (3 & (omap_readw(ARM_CKCTL) >> clk->rate_offset));
351
352         return clk->parent->rate / dsor;
353 }
354
355 static unsigned long omap1_ckctl_recalc_dsp_domain(struct clk *clk)
356 {
357         int dsor;
358
359         /* Calculate divisor encoded as 2-bit exponent
360          *
361          * The clock control bits are in DSP domain,
362          * so api_ck is needed for access.
363          * Note that DSP_CKCTL virt addr = phys addr, so
364          * we must use __raw_readw() instead of omap_readw().
365          */
366         omap1_clk_enable(&api_ck.clk);
367         dsor = 1 << (3 & (__raw_readw(DSP_CKCTL) >> clk->rate_offset));
368         omap1_clk_disable(&api_ck.clk);
369
370         return clk->parent->rate / dsor;
371 }
372
373 /* MPU virtual clock functions */
374 static int omap1_select_table_rate(struct clk * clk, unsigned long rate)
375 {
376         /* Find the highest supported frequency <= rate and switch to it */
377         struct mpu_rate * ptr;
378
379         for (ptr = rate_table; ptr->rate; ptr++) {
380                 if (ptr->xtal != ck_ref.rate)
381                         continue;
382
383                 /* DPLL1 cannot be reprogrammed without risking system crash */
384                 if (likely(ck_dpll1.rate!=0) && ptr->pll_rate != ck_dpll1.rate)
385                         continue;
386
387                 /* Can check only after xtal frequency check */
388                 if (ptr->rate <= rate)
389                         break;
390         }
391
392         if (!ptr->rate)
393                 return -EINVAL;
394
395         /*
396          * In most cases we should not need to reprogram DPLL.
397          * Reprogramming the DPLL is tricky, it must be done from SRAM.
398          * (on 730, bit 13 must always be 1)
399          */
400         if (cpu_is_omap7xx())
401                 omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val | 0x2000);
402         else
403                 omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val);
404
405         ck_dpll1.rate = ptr->pll_rate;
406         return 0;
407 }
408
409 static int omap1_clk_set_rate_dsp_domain(struct clk *clk, unsigned long rate)
410 {
411         int dsor_exp;
412         u16 regval;
413
414         dsor_exp = calc_dsor_exp(clk, rate);
415         if (dsor_exp > 3)
416                 dsor_exp = -EINVAL;
417         if (dsor_exp < 0)
418                 return dsor_exp;
419
420         regval = __raw_readw(DSP_CKCTL);
421         regval &= ~(3 << clk->rate_offset);
422         regval |= dsor_exp << clk->rate_offset;
423         __raw_writew(regval, DSP_CKCTL);
424         clk->rate = clk->parent->rate / (1 << dsor_exp);
425
426         return 0;
427 }
428
429 static long omap1_clk_round_rate_ckctl_arm(struct clk *clk, unsigned long rate)
430 {
431         int dsor_exp = calc_dsor_exp(clk, rate);
432         if (dsor_exp < 0)
433                 return dsor_exp;
434         if (dsor_exp > 3)
435                 dsor_exp = 3;
436         return clk->parent->rate / (1 << dsor_exp);
437 }
438
439 static int omap1_clk_set_rate_ckctl_arm(struct clk *clk, unsigned long rate)
440 {
441         int dsor_exp;
442         u16 regval;
443
444         dsor_exp = calc_dsor_exp(clk, rate);
445         if (dsor_exp > 3)
446                 dsor_exp = -EINVAL;
447         if (dsor_exp < 0)
448                 return dsor_exp;
449
450         regval = omap_readw(ARM_CKCTL);
451         regval &= ~(3 << clk->rate_offset);
452         regval |= dsor_exp << clk->rate_offset;
453         regval = verify_ckctl_value(regval);
454         omap_writew(regval, ARM_CKCTL);
455         clk->rate = clk->parent->rate / (1 << dsor_exp);
456         return 0;
457 }
458
459 static long omap1_round_to_table_rate(struct clk * clk, unsigned long rate)
460 {
461         /* Find the highest supported frequency <= rate */
462         struct mpu_rate * ptr;
463         long  highest_rate;
464
465         highest_rate = -EINVAL;
466
467         for (ptr = rate_table; ptr->rate; ptr++) {
468                 if (ptr->xtal != ck_ref.rate)
469                         continue;
470
471                 highest_rate = ptr->rate;
472
473                 /* Can check only after xtal frequency check */
474                 if (ptr->rate <= rate)
475                         break;
476         }
477
478         return highest_rate;
479 }
480
481 static unsigned calc_ext_dsor(unsigned long rate)
482 {
483         unsigned dsor;
484
485         /* MCLK and BCLK divisor selection is not linear:
486          * freq = 96MHz / dsor
487          *
488          * RATIO_SEL range: dsor <-> RATIO_SEL
489          * 0..6: (RATIO_SEL+2) <-> (dsor-2)
490          * 6..48:  (8+(RATIO_SEL-6)*2) <-> ((dsor-8)/2+6)
491          * Minimum dsor is 2 and maximum is 96. Odd divisors starting from 9
492          * can not be used.
493          */
494         for (dsor = 2; dsor < 96; ++dsor) {
495                 if ((dsor & 1) && dsor > 8)
496                         continue;
497                 if (rate >= 96000000 / dsor)
498                         break;
499         }
500         return dsor;
501 }
502
503 /* Only needed on 1510 */
504 static int omap1_set_uart_rate(struct clk * clk, unsigned long rate)
505 {
506         unsigned int val;
507
508         val = __raw_readl(clk->enable_reg);
509         if (rate == 12000000)
510                 val &= ~(1 << clk->enable_bit);
511         else if (rate == 48000000)
512                 val |= (1 << clk->enable_bit);
513         else
514                 return -EINVAL;
515         __raw_writel(val, clk->enable_reg);
516         clk->rate = rate;
517
518         return 0;
519 }
520
521 /* External clock (MCLK & BCLK) functions */
522 static int omap1_set_ext_clk_rate(struct clk * clk, unsigned long rate)
523 {
524         unsigned dsor;
525         __u16 ratio_bits;
526
527         dsor = calc_ext_dsor(rate);
528         clk->rate = 96000000 / dsor;
529         if (dsor > 8)
530                 ratio_bits = ((dsor - 8) / 2 + 6) << 2;
531         else
532                 ratio_bits = (dsor - 2) << 2;
533
534         ratio_bits |= __raw_readw(clk->enable_reg) & ~0xfd;
535         __raw_writew(ratio_bits, clk->enable_reg);
536
537         return 0;
538 }
539
540 static int omap1_set_sossi_rate(struct clk *clk, unsigned long rate)
541 {
542         u32 l;
543         int div;
544         unsigned long p_rate;
545
546         p_rate = clk->parent->rate;
547         /* Round towards slower frequency */
548         div = (p_rate + rate - 1) / rate;
549         div--;
550         if (div < 0 || div > 7)
551                 return -EINVAL;
552
553         l = omap_readl(MOD_CONF_CTRL_1);
554         l &= ~(7 << 17);
555         l |= div << 17;
556         omap_writel(l, MOD_CONF_CTRL_1);
557
558         clk->rate = p_rate / (div + 1);
559
560         return 0;
561 }
562
563 static long omap1_round_ext_clk_rate(struct clk * clk, unsigned long rate)
564 {
565         return 96000000 / calc_ext_dsor(rate);
566 }
567
568 static void omap1_init_ext_clk(struct clk * clk)
569 {
570         unsigned dsor;
571         __u16 ratio_bits;
572
573         /* Determine current rate and ensure clock is based on 96MHz APLL */
574         ratio_bits = __raw_readw(clk->enable_reg) & ~1;
575         __raw_writew(ratio_bits, clk->enable_reg);
576
577         ratio_bits = (ratio_bits & 0xfc) >> 2;
578         if (ratio_bits > 6)
579                 dsor = (ratio_bits - 6) * 2 + 8;
580         else
581                 dsor = ratio_bits + 2;
582
583         clk-> rate = 96000000 / dsor;
584 }
585
586 static int omap1_clk_enable(struct clk *clk)
587 {
588         int ret = 0;
589
590         if (clk->usecount++ == 0) {
591                 if (clk->parent) {
592                         ret = omap1_clk_enable(clk->parent);
593                         if (ret)
594                                 goto err;
595
596                         if (clk->flags & CLOCK_NO_IDLE_PARENT)
597                                 omap1_clk_deny_idle(clk->parent);
598                 }
599
600                 ret = clk->ops->enable(clk);
601                 if (ret) {
602                         if (clk->parent)
603                                 omap1_clk_disable(clk->parent);
604                         goto err;
605                 }
606         }
607         return ret;
608
609 err:
610         clk->usecount--;
611         return ret;
612 }
613
614 static void omap1_clk_disable(struct clk *clk)
615 {
616         if (clk->usecount > 0 && !(--clk->usecount)) {
617                 clk->ops->disable(clk);
618                 if (likely(clk->parent)) {
619                         omap1_clk_disable(clk->parent);
620                         if (clk->flags & CLOCK_NO_IDLE_PARENT)
621                                 omap1_clk_allow_idle(clk->parent);
622                 }
623         }
624 }
625
626 static int omap1_clk_enable_generic(struct clk *clk)
627 {
628         __u16 regval16;
629         __u32 regval32;
630
631         if (unlikely(clk->enable_reg == NULL)) {
632                 printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
633                        clk->name);
634                 return -EINVAL;
635         }
636
637         if (clk->flags & ENABLE_REG_32BIT) {
638                 regval32 = __raw_readl(clk->enable_reg);
639                 regval32 |= (1 << clk->enable_bit);
640                 __raw_writel(regval32, clk->enable_reg);
641         } else {
642                 regval16 = __raw_readw(clk->enable_reg);
643                 regval16 |= (1 << clk->enable_bit);
644                 __raw_writew(regval16, clk->enable_reg);
645         }
646
647         return 0;
648 }
649
650 static void omap1_clk_disable_generic(struct clk *clk)
651 {
652         __u16 regval16;
653         __u32 regval32;
654
655         if (clk->enable_reg == NULL)
656                 return;
657
658         if (clk->flags & ENABLE_REG_32BIT) {
659                 regval32 = __raw_readl(clk->enable_reg);
660                 regval32 &= ~(1 << clk->enable_bit);
661                 __raw_writel(regval32, clk->enable_reg);
662         } else {
663                 regval16 = __raw_readw(clk->enable_reg);
664                 regval16 &= ~(1 << clk->enable_bit);
665                 __raw_writew(regval16, clk->enable_reg);
666         }
667 }
668
669 static const struct clkops clkops_generic = {
670         .enable         = &omap1_clk_enable_generic,
671         .disable        = &omap1_clk_disable_generic,
672 };
673
674 static long omap1_clk_round_rate(struct clk *clk, unsigned long rate)
675 {
676         if (clk->flags & RATE_FIXED)
677                 return clk->rate;
678
679         if (clk->round_rate != NULL)
680                 return clk->round_rate(clk, rate);
681
682         return clk->rate;
683 }
684
685 static int omap1_clk_set_rate(struct clk *clk, unsigned long rate)
686 {
687         int  ret = -EINVAL;
688
689         if (clk->set_rate)
690                 ret = clk->set_rate(clk, rate);
691         return ret;
692 }
693
694 /*-------------------------------------------------------------------------
695  * Omap1 clock reset and init functions
696  *-------------------------------------------------------------------------*/
697
698 #ifdef CONFIG_OMAP_RESET_CLOCKS
699
700 static void __init omap1_clk_disable_unused(struct clk *clk)
701 {
702         __u32 regval32;
703
704         /* Clocks in the DSP domain need api_ck. Just assume bootloader
705          * has not enabled any DSP clocks */
706         if (clk->enable_reg == DSP_IDLECT2) {
707                 printk(KERN_INFO "Skipping reset check for DSP domain "
708                        "clock \"%s\"\n", clk->name);
709                 return;
710         }
711
712         /* Is the clock already disabled? */
713         if (clk->flags & ENABLE_REG_32BIT)
714                 regval32 = __raw_readl(clk->enable_reg);
715         else
716                 regval32 = __raw_readw(clk->enable_reg);
717
718         if ((regval32 & (1 << clk->enable_bit)) == 0)
719                 return;
720
721         /* FIXME: This clock seems to be necessary but no-one
722          * has asked for its activation. */
723         if (clk == &tc2_ck              /* FIX: pm.c (SRAM), CCP, Camera */
724             || clk == &ck_dpll1out.clk  /* FIX: SoSSI, SSR */
725             || clk == &arm_gpio_ck      /* FIX: GPIO code for 1510 */
726                 ) {
727                 printk(KERN_INFO "FIXME: Clock \"%s\" seems unused\n",
728                        clk->name);
729                 return;
730         }
731
732         printk(KERN_INFO "Disabling unused clock \"%s\"... ", clk->name);
733         clk->ops->disable(clk);
734         printk(" done\n");
735 }
736
737 #else
738 #define omap1_clk_disable_unused        NULL
739 #endif
740
741 static struct clk_functions omap1_clk_functions = {
742         .clk_enable             = omap1_clk_enable,
743         .clk_disable            = omap1_clk_disable,
744         .clk_round_rate         = omap1_clk_round_rate,
745         .clk_set_rate           = omap1_clk_set_rate,
746         .clk_disable_unused     = omap1_clk_disable_unused,
747 };
748
749 int __init omap1_clk_init(void)
750 {
751         struct omap_clk *c;
752         const struct omap_clock_config *info;
753         int crystal_type = 0; /* Default 12 MHz */
754         u32 reg, cpu_mask;
755
756 #ifdef CONFIG_DEBUG_LL
757         /* Resets some clocks that may be left on from bootloader,
758          * but leaves serial clocks on.
759          */
760         omap_writel(0x3 << 29, MOD_CONF_CTRL_0);
761 #endif
762
763         /* USB_REQ_EN will be disabled later if necessary (usb_dc_ck) */
764         reg = omap_readw(SOFT_REQ_REG) & (1 << 4);
765         omap_writew(reg, SOFT_REQ_REG);
766         if (!cpu_is_omap15xx())
767                 omap_writew(0, SOFT_REQ_REG2);
768
769         clk_init(&omap1_clk_functions);
770
771         /* By default all idlect1 clocks are allowed to idle */
772         arm_idlect1_mask = ~0;
773
774         for (c = omap_clks; c < omap_clks + ARRAY_SIZE(omap_clks); c++)
775                 clk_preinit(c->lk.clk);
776
777         cpu_mask = 0;
778         if (cpu_is_omap16xx())
779                 cpu_mask |= CK_16XX;
780         if (cpu_is_omap1510())
781                 cpu_mask |= CK_1510;
782         if (cpu_is_omap7xx())
783                 cpu_mask |= CK_7XX;
784         if (cpu_is_omap310())
785                 cpu_mask |= CK_310;
786
787         for (c = omap_clks; c < omap_clks + ARRAY_SIZE(omap_clks); c++)
788                 if (c->cpu & cpu_mask) {
789                         clkdev_add(&c->lk);
790                         clk_register(c->lk.clk);
791                 }
792
793         info = omap_get_config(OMAP_TAG_CLOCK, struct omap_clock_config);
794         if (info != NULL) {
795                 if (!cpu_is_omap15xx())
796                         crystal_type = info->system_clock_type;
797         }
798
799 #if defined(CONFIG_ARCH_OMAP730) || defined(CONFIG_ARCH_OMAP850)
800         ck_ref.rate = 13000000;
801 #elif defined(CONFIG_ARCH_OMAP16XX)
802         if (crystal_type == 2)
803                 ck_ref.rate = 19200000;
804 #endif
805
806         printk("Clocks: ARM_SYSST: 0x%04x DPLL_CTL: 0x%04x ARM_CKCTL: 0x%04x\n",
807                omap_readw(ARM_SYSST), omap_readw(DPLL_CTL),
808                omap_readw(ARM_CKCTL));
809
810         /* We want to be in syncronous scalable mode */
811         omap_writew(0x1000, ARM_SYSST);
812
813 #ifdef CONFIG_OMAP_CLOCKS_SET_BY_BOOTLOADER
814         /* Use values set by bootloader. Determine PLL rate and recalculate
815          * dependent clocks as if kernel had changed PLL or divisors.
816          */
817         {
818                 unsigned pll_ctl_val = omap_readw(DPLL_CTL);
819
820                 ck_dpll1.rate = ck_ref.rate; /* Base xtal rate */
821                 if (pll_ctl_val & 0x10) {
822                         /* PLL enabled, apply multiplier and divisor */
823                         if (pll_ctl_val & 0xf80)
824                                 ck_dpll1.rate *= (pll_ctl_val & 0xf80) >> 7;
825                         ck_dpll1.rate /= ((pll_ctl_val & 0x60) >> 5) + 1;
826                 } else {
827                         /* PLL disabled, apply bypass divisor */
828                         switch (pll_ctl_val & 0xc) {
829                         case 0:
830                                 break;
831                         case 0x4:
832                                 ck_dpll1.rate /= 2;
833                                 break;
834                         default:
835                                 ck_dpll1.rate /= 4;
836                                 break;
837                         }
838                 }
839         }
840 #else
841         /* Find the highest supported frequency and enable it */
842         if (omap1_select_table_rate(&virtual_ck_mpu, ~0)) {
843                 printk(KERN_ERR "System frequencies not set. Check your config.\n");
844                 /* Guess sane values (60MHz) */
845                 omap_writew(0x2290, DPLL_CTL);
846                 omap_writew(cpu_is_omap7xx() ? 0x3005 : 0x1005, ARM_CKCTL);
847                 ck_dpll1.rate = 60000000;
848         }
849 #endif
850         propagate_rate(&ck_dpll1);
851         /* Cache rates for clocks connected to ck_ref (not dpll1) */
852         propagate_rate(&ck_ref);
853         printk(KERN_INFO "Clocking rate (xtal/DPLL1/MPU): "
854                 "%ld.%01ld/%ld.%01ld/%ld.%01ld MHz\n",
855                ck_ref.rate / 1000000, (ck_ref.rate / 100000) % 10,
856                ck_dpll1.rate / 1000000, (ck_dpll1.rate / 100000) % 10,
857                arm_ck.rate / 1000000, (arm_ck.rate / 100000) % 10);
858
859 #if defined(CONFIG_MACH_OMAP_PERSEUS2) || defined(CONFIG_MACH_OMAP_FSAMPLE)
860         /* Select slicer output as OMAP input clock */
861         omap_writew(omap_readw(OMAP7XX_PCC_UPLD_CTRL) & ~0x1, OMAP7XX_PCC_UPLD_CTRL);
862 #endif
863
864         /* Amstrad Delta wants BCLK high when inactive */
865         if (machine_is_ams_delta())
866                 omap_writel(omap_readl(ULPD_CLOCK_CTRL) |
867                                 (1 << SDW_MCLK_INV_BIT),
868                                 ULPD_CLOCK_CTRL);
869
870         /* Turn off DSP and ARM_TIMXO. Make sure ARM_INTHCK is not divided */
871         /* (on 730, bit 13 must not be cleared) */
872         if (cpu_is_omap7xx())
873                 omap_writew(omap_readw(ARM_CKCTL) & 0x2fff, ARM_CKCTL);
874         else
875                 omap_writew(omap_readw(ARM_CKCTL) & 0x0fff, ARM_CKCTL);
876
877         /* Put DSP/MPUI into reset until needed */
878         omap_writew(0, ARM_RSTCT1);
879         omap_writew(1, ARM_RSTCT2);
880         omap_writew(0x400, ARM_IDLECT1);
881
882         /*
883          * According to OMAP5910 Erratum SYS_DMA_1, bit DMACK_REQ (bit 8)
884          * of the ARM_IDLECT2 register must be set to zero. The power-on
885          * default value of this bit is one.
886          */
887         omap_writew(0x0000, ARM_IDLECT2);       /* Turn LCD clock off also */
888
889         /*
890          * Only enable those clocks we will need, let the drivers
891          * enable other clocks as necessary
892          */
893         clk_enable(&armper_ck.clk);
894         clk_enable(&armxor_ck.clk);
895         clk_enable(&armtim_ck.clk); /* This should be done by timer code */
896
897         if (cpu_is_omap15xx())
898                 clk_enable(&arm_gpio_ck);
899
900         return 0;
901 }