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-rw-r--r--arch/arm/mach-at91rm9200/clock.c121
1 files changed, 101 insertions, 20 deletions
diff --git a/arch/arm/mach-at91rm9200/clock.c b/arch/arm/mach-at91rm9200/clock.c
index 8b95467c6d61..30042d2bac5f 100644
--- a/arch/arm/mach-at91rm9200/clock.c
+++ b/arch/arm/mach-at91rm9200/clock.c
@@ -32,8 +32,6 @@
32 32
33#include "generic.h" 33#include "generic.h"
34 34
35#undef DEBUG
36
37/* 35/*
38 * There's a lot more which can be done with clocks, including cpufreq 36 * There's a lot more which can be done with clocks, including cpufreq
39 * integration, slow clock mode support (for system suspend), letting 37 * integration, slow clock mode support (for system suspend), letting
@@ -41,7 +39,9 @@
41 */ 39 */
42 40
43struct clk { 41struct clk {
44 const char *name; 42 const char *name; /* unique clock name */
43 const char *function; /* function of the clock */
44 struct device *dev; /* device associated with function */
45 unsigned long rate_hz; 45 unsigned long rate_hz;
46 struct clk *parent; 46 struct clk *parent;
47 u32 pmc_mask; 47 u32 pmc_mask;
@@ -71,15 +71,14 @@ static struct clk clk32k = {
71}; 71};
72static struct clk main_clk = { 72static struct clk main_clk = {
73 .name = "main", 73 .name = "main",
74 .pmc_mask = 1 << 0, /* in PMC_SR */ 74 .pmc_mask = AT91_PMC_MOSCS, /* in PMC_SR */
75 .users = 1,
76 .id = 1, 75 .id = 1,
77 .primary = 1, 76 .primary = 1,
78}; 77};
79static struct clk plla = { 78static struct clk plla = {
80 .name = "plla", 79 .name = "plla",
81 .parent = &main_clk, 80 .parent = &main_clk,
82 .pmc_mask = 1 << 1, /* in PMC_SR */ 81 .pmc_mask = AT91_PMC_LOCKA, /* in PMC_SR */
83 .id = 2, 82 .id = 2,
84 .primary = 1, 83 .primary = 1,
85 .pll = 1, 84 .pll = 1,
@@ -105,7 +104,7 @@ static void pllb_mode(struct clk *clk, int is_on)
105static struct clk pllb = { 104static struct clk pllb = {
106 .name = "pllb", 105 .name = "pllb",
107 .parent = &main_clk, 106 .parent = &main_clk,
108 .pmc_mask = 1 << 2, /* in PMC_SR */ 107 .pmc_mask = AT91_PMC_LOCKB, /* in PMC_SR */
109 .mode = pllb_mode, 108 .mode = pllb_mode,
110 .id = 3, 109 .id = 3,
111 .primary = 1, 110 .primary = 1,
@@ -177,8 +176,7 @@ static struct clk pck3 = {
177 */ 176 */
178static struct clk mck = { 177static struct clk mck = {
179 .name = "mck", 178 .name = "mck",
180 .pmc_mask = 1 << 3, /* in PMC_SR */ 179 .pmc_mask = AT91_PMC_MCKRDY, /* in PMC_SR */
181 .users = 1, /* (must be) always on */
182}; 180};
183 181
184static void pmc_periph_mode(struct clk *clk, int is_on) 182static void pmc_periph_mode(struct clk *clk, int is_on)
@@ -249,6 +247,30 @@ static struct clk spi_clk = {
249 .pmc_mask = 1 << AT91_ID_SPI, 247 .pmc_mask = 1 << AT91_ID_SPI,
250 .mode = pmc_periph_mode, 248 .mode = pmc_periph_mode,
251}; 249};
250static struct clk pioA_clk = {
251 .name = "pioA_clk",
252 .parent = &mck,
253 .pmc_mask = 1 << AT91_ID_PIOA,
254 .mode = pmc_periph_mode,
255};
256static struct clk pioB_clk = {
257 .name = "pioB_clk",
258 .parent = &mck,
259 .pmc_mask = 1 << AT91_ID_PIOB,
260 .mode = pmc_periph_mode,
261};
262static struct clk pioC_clk = {
263 .name = "pioC_clk",
264 .parent = &mck,
265 .pmc_mask = 1 << AT91_ID_PIOC,
266 .mode = pmc_periph_mode,
267};
268static struct clk pioD_clk = {
269 .name = "pioD_clk",
270 .parent = &mck,
271 .pmc_mask = 1 << AT91_ID_PIOD,
272 .mode = pmc_periph_mode,
273};
252 274
253static struct clk *const clock_list[] = { 275static struct clk *const clock_list[] = {
254 /* four primary clocks -- MUST BE FIRST! */ 276 /* four primary clocks -- MUST BE FIRST! */
@@ -279,21 +301,46 @@ static struct clk *const clock_list[] = {
279 &udc_clk, 301 &udc_clk,
280 &twi_clk, 302 &twi_clk,
281 &spi_clk, 303 &spi_clk,
304 &pioA_clk,
305 &pioB_clk,
306 &pioC_clk,
307 &pioD_clk,
282 // ssc0..ssc2 308 // ssc0..ssc2
283 // tc0..tc5 309 // tc0..tc5
310 // irq0..irq6
284 &ohci_clk, 311 &ohci_clk,
285 &ether_clk, 312 &ether_clk,
286}; 313};
287 314
288 315
316/*
317 * Associate a particular clock with a function (eg, "uart") and device.
318 * The drivers can then request the same 'function' with several different
319 * devices and not care about which clock name to use.
320 */
321void __init at91_clock_associate(const char *id, struct device *dev, const char *func)
322{
323 struct clk *clk = clk_get(NULL, id);
324
325 if (!dev || !clk || !IS_ERR(clk_get(dev, func)))
326 return;
327
328 clk->function = func;
329 clk->dev = dev;
330}
331
289/* clocks are all static for now; no refcounting necessary */ 332/* clocks are all static for now; no refcounting necessary */
290struct clk *clk_get(struct device *dev, const char *id) 333struct clk *clk_get(struct device *dev, const char *id)
291{ 334{
292 int i; 335 int i;
293 336
294 for (i = 0; i < ARRAY_SIZE(clock_list); i++) { 337 for (i = 0; i < ARRAY_SIZE(clock_list); i++) {
295 if (strcmp(id, clock_list[i]->name) == 0) 338 struct clk *clk = clock_list[i];
296 return clock_list[i]; 339
340 if (strcmp(id, clk->name) == 0)
341 return clk;
342 if (clk->function && (dev == clk->dev) && strcmp(id, clk->function) == 0)
343 return clk;
297 } 344 }
298 345
299 return ERR_PTR(-ENOENT); 346 return ERR_PTR(-ENOENT);
@@ -593,6 +640,30 @@ fail:
593 return 0; 640 return 0;
594} 641}
595 642
643
644/*
645 * Several unused clocks may be active. Turn them off.
646 */
647static void at91_periphclk_reset(void)
648{
649 unsigned long reg;
650 int i;
651
652 reg = at91_sys_read(AT91_PMC_PCSR);
653
654 for (i = 0; i < ARRAY_SIZE(clock_list); i++) {
655 struct clk *clk = clock_list[i];
656
657 if (clk->mode != pmc_periph_mode)
658 continue;
659
660 if (clk->users > 0)
661 reg &= ~clk->pmc_mask;
662 }
663
664 at91_sys_write(AT91_PMC_PCDR, reg);
665}
666
596int __init at91_clock_init(unsigned long main_clock) 667int __init at91_clock_init(unsigned long main_clock)
597{ 668{
598 unsigned tmp, freq, mckr; 669 unsigned tmp, freq, mckr;
@@ -626,7 +697,6 @@ int __init at91_clock_init(unsigned long main_clock)
626 */ 697 */
627 at91_pllb_usb_init = at91_pll_calc(main_clock, 48000000 * 2) | AT91_PMC_USB96M; 698 at91_pllb_usb_init = at91_pll_calc(main_clock, 48000000 * 2) | AT91_PMC_USB96M;
628 pllb.rate_hz = at91_pll_rate(&pllb, main_clock, at91_pllb_usb_init); 699 pllb.rate_hz = at91_pll_rate(&pllb, main_clock, at91_pllb_usb_init);
629 at91_sys_write(AT91_PMC_PCDR, (1 << AT91_ID_UHP) | (1 << AT91_ID_UDP));
630 at91_sys_write(AT91_PMC_SCDR, AT91_PMC_UHP | AT91_PMC_UDP); 700 at91_sys_write(AT91_PMC_SCDR, AT91_PMC_UHP | AT91_PMC_UDP);
631 at91_sys_write(AT91_CKGR_PLLBR, 0); 701 at91_sys_write(AT91_CKGR_PLLBR, 0);
632 at91_sys_write(AT91_PMC_SCER, AT91_PMC_MCKUDP); 702 at91_sys_write(AT91_PMC_SCER, AT91_PMC_MCKUDP);
@@ -640,11 +710,13 @@ int __init at91_clock_init(unsigned long main_clock)
640 */ 710 */
641 mckr = at91_sys_read(AT91_PMC_MCKR); 711 mckr = at91_sys_read(AT91_PMC_MCKR);
642 mck.parent = clock_list[mckr & AT91_PMC_CSS]; 712 mck.parent = clock_list[mckr & AT91_PMC_CSS];
643 mck.parent->users++;
644 freq = mck.parent->rate_hz; 713 freq = mck.parent->rate_hz;
645 freq /= (1 << ((mckr >> 2) & 3)); /* prescale */ 714 freq /= (1 << ((mckr >> 2) & 3)); /* prescale */
646 mck.rate_hz = freq / (1 + ((mckr >> 8) & 3)); /* mdiv */ 715 mck.rate_hz = freq / (1 + ((mckr >> 8) & 3)); /* mdiv */
647 716
717 /* MCK and CPU clock are "always on" */
718 clk_enable(&mck);
719
648 printk("Clocks: CPU %u MHz, master %u MHz, main %u.%03u MHz\n", 720 printk("Clocks: CPU %u MHz, master %u MHz, main %u.%03u MHz\n",
649 freq / 1000000, (unsigned) mck.rate_hz / 1000000, 721 freq / 1000000, (unsigned) mck.rate_hz / 1000000,
650 (unsigned) main_clock / 1000000, 722 (unsigned) main_clock / 1000000,
@@ -663,19 +735,28 @@ int __init at91_clock_init(unsigned long main_clock)
663 continue; 735 continue;
664 736
665 pckr = at91_sys_read(AT91_PMC_PCKR(clk->id)); 737 pckr = at91_sys_read(AT91_PMC_PCKR(clk->id));
666 parent = clock_list[pckr & 3]; 738 parent = clock_list[pckr & AT91_PMC_CSS];
667 clk->parent = parent; 739 clk->parent = parent;
668 clk->rate_hz = parent->rate_hz / (1 << ((pckr >> 2) & 3)); 740 clk->rate_hz = parent->rate_hz / (1 << ((pckr >> 2) & 3));
741
742 if (clk->users == 0) {
743 /* not being used, so switch it off */
744 at91_sys_write(AT91_PMC_SCDR, clk->pmc_mask);
745 }
669 } 746 }
670#else 747#else
671 /* disable unused clocks */ 748 /* disable all programmable clocks */
672 at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK0 | AT91_PMC_PCK1 | AT91_PMC_PCK2 | AT91_PMC_PCK3); 749 at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK0 | AT91_PMC_PCK1 | AT91_PMC_PCK2 | AT91_PMC_PCK3);
673#endif /* CONFIG_AT91_PROGRAMMABLE_CLOCKS */ 750#endif
674 751
675 /* FIXME several unused clocks may still be active... provide 752 /* enable the PIO clocks */
676 * a CONFIG option to turn off all unused clocks at some point 753 clk_enable(&pioA_clk);
677 * before driver init starts. 754 clk_enable(&pioB_clk);
678 */ 755 clk_enable(&pioC_clk);
756 clk_enable(&pioD_clk);
757
758 /* disable all other unused peripheral clocks */
759 at91_periphclk_reset();
679 760
680 return 0; 761 return 0;
681} 762}