diff options
Diffstat (limited to 'arch/arm/mach-at91rm9200/clock.c')
| -rw-r--r-- | arch/arm/mach-at91rm9200/clock.c | 121 |
1 files changed, 101 insertions, 20 deletions
diff --git a/arch/arm/mach-at91rm9200/clock.c b/arch/arm/mach-at91rm9200/clock.c index 8b95467c6d6..30042d2bac5 100644 --- a/arch/arm/mach-at91rm9200/clock.c +++ b/arch/arm/mach-at91rm9200/clock.c @@ -32,8 +32,6 @@ #include "generic.h" -#undef DEBUG - /* * There's a lot more which can be done with clocks, including cpufreq * integration, slow clock mode support (for system suspend), letting @@ -41,7 +39,9 @@ */ struct clk { - const char *name; + const char *name; /* unique clock name */ + const char *function; /* function of the clock */ + struct device *dev; /* device associated with function */ unsigned long rate_hz; struct clk *parent; u32 pmc_mask; @@ -71,15 +71,14 @@ static struct clk clk32k = { }; static struct clk main_clk = { .name = "main", - .pmc_mask = 1 << 0, /* in PMC_SR */ - .users = 1, + .pmc_mask = AT91_PMC_MOSCS, /* in PMC_SR */ .id = 1, .primary = 1, }; static struct clk plla = { .name = "plla", .parent = &main_clk, - .pmc_mask = 1 << 1, /* in PMC_SR */ + .pmc_mask = AT91_PMC_LOCKA, /* in PMC_SR */ .id = 2, .primary = 1, .pll = 1, @@ -105,7 +104,7 @@ static void pllb_mode(struct clk *clk, int is_on) static struct clk pllb = { .name = "pllb", .parent = &main_clk, - .pmc_mask = 1 << 2, /* in PMC_SR */ + .pmc_mask = AT91_PMC_LOCKB, /* in PMC_SR */ .mode = pllb_mode, .id = 3, .primary = 1, @@ -177,8 +176,7 @@ static struct clk pck3 = { */ static struct clk mck = { .name = "mck", - .pmc_mask = 1 << 3, /* in PMC_SR */ - .users = 1, /* (must be) always on */ + .pmc_mask = AT91_PMC_MCKRDY, /* in PMC_SR */ }; static void pmc_periph_mode(struct clk *clk, int is_on) @@ -249,6 +247,30 @@ static struct clk spi_clk = { .pmc_mask = 1 << AT91_ID_SPI, .mode = pmc_periph_mode, }; +static struct clk pioA_clk = { + .name = "pioA_clk", + .parent = &mck, + .pmc_mask = 1 << AT91_ID_PIOA, + .mode = pmc_periph_mode, +}; +static struct clk pioB_clk = { + .name = "pioB_clk", + .parent = &mck, + .pmc_mask = 1 << AT91_ID_PIOB, + .mode = pmc_periph_mode, +}; +static struct clk pioC_clk = { + .name = "pioC_clk", + .parent = &mck, + .pmc_mask = 1 << AT91_ID_PIOC, + .mode = pmc_periph_mode, +}; +static struct clk pioD_clk = { + .name = "pioD_clk", + .parent = &mck, + .pmc_mask = 1 << AT91_ID_PIOD, + .mode = pmc_periph_mode, +}; static struct clk *const clock_list[] = { /* four primary clocks -- MUST BE FIRST! */ @@ -279,21 +301,46 @@ static struct clk *const clock_list[] = { &udc_clk, &twi_clk, &spi_clk, + &pioA_clk, + &pioB_clk, + &pioC_clk, + &pioD_clk, // ssc0..ssc2 // tc0..tc5 + // irq0..irq6 &ohci_clk, ðer_clk, }; +/* + * Associate a particular clock with a function (eg, "uart") and device. + * The drivers can then request the same 'function' with several different + * devices and not care about which clock name to use. + */ +void __init at91_clock_associate(const char *id, struct device *dev, const char *func) +{ + struct clk *clk = clk_get(NULL, id); + + if (!dev || !clk || !IS_ERR(clk_get(dev, func))) + return; + + clk->function = func; + clk->dev = dev; +} + /* clocks are all static for now; no refcounting necessary */ struct clk *clk_get(struct device *dev, const char *id) { int i; for (i = 0; i < ARRAY_SIZE(clock_list); i++) { - if (strcmp(id, clock_list[i]->name) == 0) - return clock_list[i]; + struct clk *clk = clock_list[i]; + + if (strcmp(id, clk->name) == 0) + return clk; + if (clk->function && (dev == clk->dev) && strcmp(id, clk->function) == 0) + return clk; } return ERR_PTR(-ENOENT); @@ -593,6 +640,30 @@ fail: return 0; } + +/* + * Several unused clocks may be active. Turn them off. + */ +static void at91_periphclk_reset(void) +{ + unsigned long reg; + int i; + + reg = at91_sys_read(AT91_PMC_PCSR); + + for (i = 0; i < ARRAY_SIZE(clock_list); i++) { + struct clk *clk = clock_list[i]; + + if (clk->mode != pmc_periph_mode) + continue; + + if (clk->users > 0) + reg &= ~clk->pmc_mask; + } + + at91_sys_write(AT91_PMC_PCDR, reg); +} + int __init at91_clock_init(unsigned long main_clock) { unsigned tmp, freq, mckr; @@ -626,7 +697,6 @@ int __init at91_clock_init(unsigned long main_clock) */ at91_pllb_usb_init = at91_pll_calc(main_clock, 48000000 * 2) | AT91_PMC_USB96M; pllb.rate_hz = at91_pll_rate(&pllb, main_clock, at91_pllb_usb_init); - at91_sys_write(AT91_PMC_PCDR, (1 << AT91_ID_UHP) | (1 << AT91_ID_UDP)); at91_sys_write(AT91_PMC_SCDR, AT91_PMC_UHP | AT91_PMC_UDP); at91_sys_write(AT91_CKGR_PLLBR, 0); at91_sys_write(AT91_PMC_SCER, AT91_PMC_MCKUDP); @@ -640,11 +710,13 @@ int __init at91_clock_init(unsigned long main_clock) */ mckr = at91_sys_read(AT91_PMC_MCKR); mck.parent = clock_list[mckr & AT91_PMC_CSS]; - mck.parent->users++; freq = mck.parent->rate_hz; freq /= (1 << ((mckr >> 2) & 3)); /* prescale */ mck.rate_hz = freq / (1 + ((mckr >> 8) & 3)); /* mdiv */ + /* MCK and CPU clock are "always on" */ + clk_enable(&mck); + printk("Clocks: CPU %u MHz, master %u MHz, main %u.%03u MHz\n", freq / 1000000, (unsigned) mck.rate_hz / 1000000, (unsigned) main_clock / 1000000, @@ -663,19 +735,28 @@ int __init at91_clock_init(unsigned long main_clock) continue; pckr = at91_sys_read(AT91_PMC_PCKR(clk->id)); - parent = clock_list[pckr & 3]; + parent = clock_list[pckr & AT91_PMC_CSS]; clk->parent = parent; clk->rate_hz = parent->rate_hz / (1 << ((pckr >> 2) & 3)); + + if (clk->users == 0) { + /* not being used, so switch it off */ + at91_sys_write(AT91_PMC_SCDR, clk->pmc_mask); + } } #else - /* disable unused clocks */ + /* disable all programmable clocks */ at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK0 | AT91_PMC_PCK1 | AT91_PMC_PCK2 | AT91_PMC_PCK3); -#endif /* CONFIG_AT91_PROGRAMMABLE_CLOCKS */ +#endif - /* FIXME several unused clocks may still be active... provide - * a CONFIG option to turn off all unused clocks at some point - * before driver init starts. - */ + /* enable the PIO clocks */ + clk_enable(&pioA_clk); + clk_enable(&pioB_clk); + clk_enable(&pioC_clk); + clk_enable(&pioD_clk); + + /* disable all other unused peripheral clocks */ + at91_periphclk_reset(); return 0; } |