Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee13...
[pandora-kernel.git] / arch / arm / mach-at91rm9200 / clock.c
index 8b95467..a43b061 100644 (file)
 #include <asm/io.h>
 #include <asm/mach-types.h>
 
-#include <asm/arch/hardware.h>
-#include <asm/arch/board.h>            /* for master clock global */
+#include <asm/hardware.h>
 
-#include "generic.h"
+#include "clock.h"
 
-#undef DEBUG
 
 /*
  * There's a lot more which can be done with clocks, including cpufreq
  * PLLB be used at other rates (on boards that don't need USB), etc.
  */
 
-struct clk {
-       const char      *name;
-       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
@@ -67,22 +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       = 1 << 0,       /* in PMC_SR */
-       .users          = 1,
+       .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       = 1 << 1,       /* in PMC_SR */
+       .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)
@@ -95,6 +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 {
@@ -105,11 +96,10 @@ 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,
-       .pll            = 1,
+       .type           = CLK_TYPE_PRIMARY | CLK_TYPE_PLL,
 };
 
 static void pmc_sys_mode(struct clk *clk, int is_on)
@@ -134,41 +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
@@ -177,8 +132,7 @@ 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)
@@ -189,111 +143,48 @@ 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 << AT91_ID_UDP,
-       .mode           = pmc_periph_mode,
-};
-static struct clk ohci_clk = {
-       .name           = "ohci_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_UHP,
-       .mode           = pmc_periph_mode,
-};
-static struct clk ether_clk = {
-       .name           = "ether_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_EMAC,
-       .mode           = pmc_periph_mode,
-};
-static struct clk mmc_clk = {
-       .name           = "mci_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_MCI,
-       .mode           = pmc_periph_mode,
-};
-static struct clk twi_clk = {
-       .name           = "twi_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_TWI,
-       .mode           = pmc_periph_mode,
-};
-static struct clk usart0_clk = {
-       .name           = "usart0_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_US0,
-       .mode           = pmc_periph_mode,
-};
-static struct clk usart1_clk = {
-       .name           = "usart1_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_US1,
-       .mode           = pmc_periph_mode,
-};
-static struct clk usart2_clk = {
-       .name           = "usart2_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_US2,
-       .mode           = pmc_periph_mode,
-};
-static struct clk usart3_clk = {
-       .name           = "usart3_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_US3,
-       .mode           = pmc_periph_mode,
-};
-static struct clk spi_clk = {
-       .name           = "spi0_clk",
-       .parent         = &mck,
-       .pmc_mask       = 1 << AT91_ID_SPI,
-       .mode           = pmc_periph_mode,
-};
-
-static struct clk *const clock_list[] = {
-       /* four primary clocks -- MUST BE FIRST! */
-       &clk32k,
-       &main_clk,
-       &plla,
-       &pllb,
+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;
+       }
 
-       /* PLLB children (USB) */
-       &udpck,
-       &uhpck,
+       return NULL;
+}
 
-#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS
-       /* programmable clocks */
-       &pck0,
-       &pck1,
-       &pck2,
-       &pck3,
-#endif /* CONFIG_AT91_PROGRAMMABLE_CLOCKS */
+/*
+ * 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);
 
-       /* MCK and peripherals */
-       &mck,
-       &usart0_clk,
-       &usart1_clk,
-       &usart2_clk,
-       &usart3_clk,
-       &mmc_clk,
-       &udc_clk,
-       &twi_clk,
-       &spi_clk,
-       // ssc0..ssc2
-       // tc0..tc5
-       &ohci_clk,
-       &ether_clk,
-};
+       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 */
+/* clocks cannot be de-registered no refcounting necessary */
 struct clk *clk_get(struct device *dev, const char *id)
 {
-       int i;
+       struct clk *clk;
 
-       for (i = 0; i < ARRAY_SIZE(clock_list); i++) {
-               if (strcmp(id, clock_list[i]->name) == 0)
-                       return clock_list[i];
+       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)
+                       return clk;
        }
 
        return ERR_PTR(-ENOENT);
@@ -377,7 +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);
 
@@ -399,7 +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;
@@ -437,7 +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);
 
@@ -450,6 +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 */
 
 /*------------------------------------------------------------------------*/
@@ -459,6 +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));
@@ -476,9 +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";
@@ -521,6 +424,28 @@ postcore_initcall(at91_clk_debugfs_init);
 
 #endif
 
+/*------------------------------------------------------------------------*/
+
+/* 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)
@@ -593,11 +518,46 @@ fail:
        return 0;
 }
 
+/*
+ * Several unused clocks may be active.  Turn them off.
+ */
+static void __init at91_periphclk_reset(void)
+{
+       unsigned long reg;
+       struct clk *clk;
+
+       reg = at91_sys_read(AT91_PMC_PCSR);
+
+       list_for_each_entry(clk, &clocks, node) {
+               if (clk->mode != pmc_periph_mode)
+                       continue;
+
+               if (clk->users > 0)
+                       reg &= ~clk->pmc_mask;
+       }
+
+       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,
@@ -626,7 +586,6 @@ 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);
@@ -639,43 +598,28 @@ 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->users++;
+       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);
+
        printk("Clocks: CPU %u MHz, master %u MHz, main %u.%03u MHz\n",
                freq / 1000000, (unsigned) mck.rate_hz / 1000000,
                (unsigned) main_clock / 1000000,
                ((unsigned) main_clock % 1000000) / 1000);
 
-       /* FIXME get rid of master_clock global */
-       at91_master_clock = mck.rate_hz;
-
-#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 & 3];
-               clk->parent = parent;
-               clk->rate_hz = parent->rate_hz / (1 << ((pckr >> 2) & 3));
-       }
-#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 */
 
-       /* 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.
-        */
+       /* disable all other unused peripheral clocks */
+       at91_periphclk_reset();
 
        return 0;
 }