diff options
Diffstat (limited to 'arch/arm/mach-at91rm9200/clock.c')
| -rw-r--r-- | arch/arm/mach-at91rm9200/clock.c | 324 |
1 files changed, 95 insertions, 229 deletions
diff --git a/arch/arm/mach-at91rm9200/clock.c b/arch/arm/mach-at91rm9200/clock.c index 5b7892277be..a43b061a7c8 100644 --- a/arch/arm/mach-at91rm9200/clock.c +++ b/arch/arm/mach-at91rm9200/clock.c @@ -29,7 +29,7 @@ #include <asm/hardware.h> -#include "generic.h" +#include "clock.h" /* @@ -38,23 +38,15 @@ * PLLB be used at other rates (on boards that don't need USB), etc. */ -struct clk { - 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; - void (*mode)(struct clk *, int); - unsigned id:2; /* PCK0..3, or 32k/main/a/b */ - unsigned primary:1; - unsigned pll:1; - unsigned programmable:1; - u16 users; -}; +#define clk_is_primary(x) ((x)->type & CLK_TYPE_PRIMARY) +#define clk_is_programmable(x) ((x)->type & CLK_TYPE_PROGRAMMABLE) +#define clk_is_peripheral(x) ((x)->type & CLK_TYPE_PERIPHERAL) + + +static LIST_HEAD(clocks); +static DEFINE_SPINLOCK(clk_lock); -static spinlock_t clk_lock; -static u32 at91_pllb_usb_init; +static u32 at91_pllb_usb_init; /* * Four primary clock sources: two crystal oscillators (32K, main), and @@ -67,21 +59,20 @@ static struct clk clk32k = { .rate_hz = AT91_SLOW_CLOCK, .users = 1, /* always on */ .id = 0, - .primary = 1, + .type = CLK_TYPE_PRIMARY, }; static struct clk main_clk = { .name = "main", .pmc_mask = AT91_PMC_MOSCS, /* in PMC_SR */ .id = 1, - .primary = 1, + .type = CLK_TYPE_PRIMARY, }; static struct clk plla = { .name = "plla", .parent = &main_clk, .pmc_mask = AT91_PMC_LOCKA, /* in PMC_SR */ .id = 2, - .primary = 1, - .pll = 1, + .type = CLK_TYPE_PRIMARY | CLK_TYPE_PLL, }; static void pllb_mode(struct clk *clk, int is_on) @@ -94,6 +85,7 @@ static void pllb_mode(struct clk *clk, int is_on) } else value = 0; + // REVISIT: Add work-around for AT91RM9200 Errata #26 ? at91_sys_write(AT91_CKGR_PLLBR, value); do { @@ -107,8 +99,7 @@ static struct clk pllb = { .pmc_mask = AT91_PMC_LOCKB, /* in PMC_SR */ .mode = pllb_mode, .id = 3, - .primary = 1, - .pll = 1, + .type = CLK_TYPE_PRIMARY | CLK_TYPE_PLL, }; static void pmc_sys_mode(struct clk *clk, int is_on) @@ -133,41 +124,6 @@ static struct clk uhpck = { .mode = pmc_sys_mode, }; -#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS -/* - * The four programmable clocks can be parented by any primary clock. - * You must configure pin multiplexing to bring these signals out. - */ -static struct clk pck0 = { - .name = "pck0", - .pmc_mask = AT91_PMC_PCK0, - .mode = pmc_sys_mode, - .programmable = 1, - .id = 0, -}; -static struct clk pck1 = { - .name = "pck1", - .pmc_mask = AT91_PMC_PCK1, - .mode = pmc_sys_mode, - .programmable = 1, - .id = 1, -}; -static struct clk pck2 = { - .name = "pck2", - .pmc_mask = AT91_PMC_PCK2, - .mode = pmc_sys_mode, - .programmable = 1, - .id = 2, -}; -static struct clk pck3 = { - .name = "pck3", - .pmc_mask = AT91_PMC_PCK3, - .mode = pmc_sys_mode, - .programmable = 1, - .id = 3, -}; -#endif /* CONFIG_AT91_PROGRAMMABLE_CLOCKS */ - /* * The master clock is divided from the CPU clock (by 1-4). It's used for @@ -187,131 +143,21 @@ static void pmc_periph_mode(struct clk *clk, int is_on) at91_sys_write(AT91_PMC_PCDR, clk->pmc_mask); } -static struct clk udc_clk = { - .name = "udc_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_UDP, - .mode = pmc_periph_mode, -}; -static struct clk ohci_clk = { - .name = "ohci_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_UHP, - .mode = pmc_periph_mode, -}; -static struct clk ether_clk = { - .name = "ether_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_EMAC, - .mode = pmc_periph_mode, -}; -static struct clk mmc_clk = { - .name = "mci_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_MCI, - .mode = pmc_periph_mode, -}; -static struct clk twi_clk = { - .name = "twi_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_TWI, - .mode = pmc_periph_mode, -}; -static struct clk usart0_clk = { - .name = "usart0_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_US0, - .mode = pmc_periph_mode, -}; -static struct clk usart1_clk = { - .name = "usart1_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_US1, - .mode = pmc_periph_mode, -}; -static struct clk usart2_clk = { - .name = "usart2_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_US2, - .mode = pmc_periph_mode, -}; -static struct clk usart3_clk = { - .name = "usart3_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_US3, - .mode = pmc_periph_mode, -}; -static struct clk spi_clk = { - .name = "spi0_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_SPI, - .mode = pmc_periph_mode, -}; -static struct clk pioA_clk = { - .name = "pioA_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_PIOA, - .mode = pmc_periph_mode, -}; -static struct clk pioB_clk = { - .name = "pioB_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_PIOB, - .mode = pmc_periph_mode, -}; -static struct clk pioC_clk = { - .name = "pioC_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_PIOC, - .mode = pmc_periph_mode, -}; -static struct clk pioD_clk = { - .name = "pioD_clk", - .parent = &mck, - .pmc_mask = 1 << AT91RM9200_ID_PIOD, - .mode = pmc_periph_mode, -}; - -static struct clk *const clock_list[] = { - /* four primary clocks -- MUST BE FIRST! */ - &clk32k, - &main_clk, - &plla, - &pllb, - - /* PLLB children (USB) */ - &udpck, - &uhpck, - -#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS - /* programmable clocks */ - &pck0, - &pck1, - &pck2, - &pck3, -#endif /* CONFIG_AT91_PROGRAMMABLE_CLOCKS */ - - /* MCK and peripherals */ - &mck, - &usart0_clk, - &usart1_clk, - &usart2_clk, - &usart3_clk, - &mmc_clk, - &udc_clk, - &twi_clk, - &spi_clk, - &pioA_clk, - &pioB_clk, - &pioC_clk, - &pioD_clk, - // ssc0..ssc2 - // tc0..tc5 - // irq0..irq6 - &ohci_clk, - ðer_clk, -}; +static struct clk __init *at91_css_to_clk(unsigned long css) +{ + switch (css) { + case AT91_PMC_CSS_SLOW: + return &clk32k; + case AT91_PMC_CSS_MAIN: + return &main_clk; + case AT91_PMC_CSS_PLLA: + return &plla; + case AT91_PMC_CSS_PLLB: + return &pllb; + } + return NULL; +} /* * Associate a particular clock with a function (eg, "uart") and device. @@ -329,14 +175,12 @@ void __init at91_clock_associate(const char *id, struct device *dev, const char clk->dev = dev; } -/* clocks are all static for now; no refcounting necessary */ +/* clocks cannot be de-registered no refcounting necessary */ struct clk *clk_get(struct device *dev, const char *id) { - int i; - - for (i = 0; i < ARRAY_SIZE(clock_list); i++) { - struct clk *clk = clock_list[i]; + struct clk *clk; + list_for_each_entry(clk, &clocks, node) { if (strcmp(id, clk->name) == 0) return clk; if (clk->function && (dev == clk->dev) && strcmp(id, clk->function) == 0) @@ -424,7 +268,7 @@ long clk_round_rate(struct clk *clk, unsigned long rate) unsigned prescale; unsigned long actual; - if (!clk->programmable) + if (!clk_is_programmable(clk)) return -EINVAL; spin_lock_irqsave(&clk_lock, flags); @@ -446,7 +290,7 @@ int clk_set_rate(struct clk *clk, unsigned long rate) unsigned prescale; unsigned long actual; - if (!clk->programmable) + if (!clk_is_programmable(clk)) return -EINVAL; if (clk->users) return -EBUSY; @@ -484,7 +328,7 @@ int clk_set_parent(struct clk *clk, struct clk *parent) if (clk->users) return -EBUSY; - if (!parent->primary || !clk->programmable) + if (!clk_is_primary(parent) || !clk_is_programmable(clk)) return -EINVAL; spin_lock_irqsave(&clk_lock, flags); @@ -497,6 +341,18 @@ int clk_set_parent(struct clk *clk, struct clk *parent) } EXPORT_SYMBOL(clk_set_parent); +/* establish PCK0..PCK3 parentage and rate */ +static void init_programmable_clock(struct clk *clk) +{ + struct clk *parent; + u32 pckr; + + pckr = at91_sys_read(AT91_PMC_PCKR(clk->id)); + parent = at91_css_to_clk(pckr & AT91_PMC_CSS); + clk->parent = parent; + clk->rate_hz = parent->rate_hz / (1 << ((pckr >> 2) & 3)); +} + #endif /* CONFIG_AT91_PROGRAMMABLE_CLOCKS */ /*------------------------------------------------------------------------*/ @@ -506,6 +362,7 @@ EXPORT_SYMBOL(clk_set_parent); static int at91_clk_show(struct seq_file *s, void *unused) { u32 scsr, pcsr, sr; + struct clk *clk; unsigned i; seq_printf(s, "SCSR = %8x\n", scsr = at91_sys_read(AT91_PMC_SCSR)); @@ -523,9 +380,8 @@ static int at91_clk_show(struct seq_file *s, void *unused) seq_printf(s, "\n"); - for (i = 0; i < ARRAY_SIZE(clock_list); i++) { - char *state; - struct clk *clk = clock_list[i]; + list_for_each_entry(clk, &clocks, node) { + char *state; if (clk->mode == pmc_sys_mode) state = (scsr & clk->pmc_mask) ? "on" : "off"; @@ -570,6 +426,28 @@ postcore_initcall(at91_clk_debugfs_init); /*------------------------------------------------------------------------*/ +/* Register a new clock */ +int __init clk_register(struct clk *clk) +{ + if (clk_is_peripheral(clk)) { + clk->parent = &mck; + clk->mode = pmc_periph_mode; + list_add_tail(&clk->node, &clocks); + } +#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS + else if (clk_is_programmable(clk)) { + clk->mode = pmc_sys_mode; + init_programmable_clock(clk); + list_add_tail(&clk->node, &clocks); + } +#endif + + return 0; +} + + +/*------------------------------------------------------------------------*/ + static u32 __init at91_pll_rate(struct clk *pll, u32 freq, u32 reg) { unsigned mul, div; @@ -640,20 +518,17 @@ fail: return 0; } - /* * Several unused clocks may be active. Turn them off. */ -static void at91_periphclk_reset(void) +static void __init at91_periphclk_reset(void) { unsigned long reg; - int i; + struct clk *clk; reg = at91_sys_read(AT91_PMC_PCSR); - for (i = 0; i < ARRAY_SIZE(clock_list); i++) { - struct clk *clk = clock_list[i]; - + list_for_each_entry(clk, &clocks, node) { if (clk->mode != pmc_periph_mode) continue; @@ -664,11 +539,25 @@ static void at91_periphclk_reset(void) at91_sys_write(AT91_PMC_PCDR, reg); } +static struct clk *const standard_pmc_clocks[] __initdata = { + /* four primary clocks */ + &clk32k, + &main_clk, + &plla, + &pllb, + + /* PLLB children (USB) */ + &udpck, + &uhpck, + + /* MCK */ + &mck +}; + int __init at91_clock_init(unsigned long main_clock) { unsigned tmp, freq, mckr; - - spin_lock_init(&clk_lock); + int i; /* * When the bootloader initialized the main oscillator correctly, @@ -709,11 +598,15 @@ int __init at91_clock_init(unsigned long main_clock) * For now, assume this parentage won't change. */ mckr = at91_sys_read(AT91_PMC_MCKR); - mck.parent = clock_list[mckr & AT91_PMC_CSS]; + mck.parent = at91_css_to_clk(mckr & AT91_PMC_CSS); freq = mck.parent->rate_hz; freq /= (1 << ((mckr >> 2) & 3)); /* prescale */ mck.rate_hz = freq / (1 + ((mckr >> 8) & 3)); /* mdiv */ + /* Register the PMC's standard clocks */ + for (i = 0; i < ARRAY_SIZE(standard_pmc_clocks); i++) + list_add_tail(&standard_pmc_clocks[i]->node, &clocks); + /* MCK and CPU clock are "always on" */ clk_enable(&mck); @@ -722,35 +615,8 @@ int __init at91_clock_init(unsigned long main_clock) (unsigned) main_clock / 1000000, ((unsigned) main_clock % 1000000) / 1000); -#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS - /* establish PCK0..PCK3 parentage */ - for (tmp = 0; tmp < ARRAY_SIZE(clock_list); tmp++) { - struct clk *clk = clock_list[tmp], *parent; - u32 pckr; - - if (!clk->programmable) - continue; - - pckr = at91_sys_read(AT91_PMC_PCKR(clk->id)); - 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 all programmable clocks */ at91_sys_write(AT91_PMC_SCDR, AT91_PMC_PCK0 | AT91_PMC_PCK1 | AT91_PMC_PCK2 | AT91_PMC_PCK3); -#endif - - /* 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(); |