[ARM] 4260/1: clocksource support for Versatile platform

[linux-2.6-omap-h63xx.git] / arch / arm / mach-versatile / core.c

diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c
index 2aa150b57ba109066c7c969170eacad562d0e554..08a9fe6eeadb48c2780cfe9f90f4294c3972ecfd 100644 (file)
--- a/arch/arm/mach-versatile/core.c
+++ b/arch/arm/mach-versatile/core.c
@@ -26,7 +26,9 @@
 #include <linux/interrupt.h>
 #include <linux/amba/bus.h>
 #include <linux/amba/clcd.h>
+#include <linux/clocksource.h>
 
+#include <asm/cnt32_to_63.h>
 #include <asm/system.h>
 #include <asm/hardware.h>
 #include <asm/io.h>
@@ -77,7 +79,7 @@ static struct irq_chip sic_chip = {
 };
 
 static void
-sic_handle_irq(unsigned int irq, struct irqdesc *desc)
+sic_handle_irq(unsigned int irq, struct irq_desc *desc)
 {
        unsigned long status = readl(VA_SIC_BASE + SIC_IRQ_STATUS);
 
@@ -123,7 +125,7 @@ void __init versatile_init_irq(void)
        for (i = IRQ_SIC_START; i <= IRQ_SIC_END; i++) {
                if ((PIC_MASK & (1 << (i - IRQ_SIC_START))) == 0) {
                        set_irq_chip(i, &sic_chip);
-                       set_irq_handler(i, do_level_IRQ);
+                       set_irq_handler(i, handle_level_irq);
                        set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
                }
        }
@@ -188,12 +190,12 @@ static struct map_desc versatile_io_desc[] __initdata = {
                .length         = SZ_4K,
                .type           = MT_DEVICE
        }, {
-               .virtual        =  VERSATILE_PCI_VIRT_BASE,
+               .virtual        =  (unsigned long)VERSATILE_PCI_VIRT_BASE,
                .pfn            = __phys_to_pfn(VERSATILE_PCI_BASE),
                .length         = VERSATILE_PCI_BASE_SIZE,
                .type           = MT_DEVICE
        }, {
-               .virtual        =  VERSATILE_PCI_CFG_VIRT_BASE,
+               .virtual        =  (unsigned long)VERSATILE_PCI_CFG_VIRT_BASE,
                .pfn            = __phys_to_pfn(VERSATILE_PCI_CFG_BASE),
                .length         = VERSATILE_PCI_CFG_BASE_SIZE,
                .type           = MT_DEVICE
@@ -228,14 +230,19 @@ void __init versatile_map_io(void)
 
 /*
  * This is the Versatile sched_clock implementation.  This has
- * a resolution of 41.7ns, and a maximum value of about 179s.
+ * a resolution of 41.7ns, and a maximum value of about 35583 days.
+ *
+ * The return value is guaranteed to be monotonic in that range as
+ * long as there is always less than 89 seconds between successive
+ * calls to this function.
  */
 unsigned long long sched_clock(void)
 {
-       unsigned long long v;
+       unsigned long long v = cnt32_to_63(readl(VERSATILE_REFCOUNTER));
 
-       v = (unsigned long long)readl(VERSATILE_REFCOUNTER) * 125;
-       do_div(v, 3);
+       /* the <<1 gets rid of the cnt_32_to_63 top bit saving on a bic insn */
+       v *= 125<<1;
+       do_div(v, 3<<1);
 
        return v;
 }
@@ -319,6 +326,19 @@ static struct platform_device smc91x_device = {
        .resource       = smc91x_resources,
 };
 
+static struct resource versatile_i2c_resource = {
+       .start                  = VERSATILE_I2C_BASE,
+       .end                    = VERSATILE_I2C_BASE + SZ_4K - 1,
+       .flags                  = IORESOURCE_MEM,
+};
+
+static struct platform_device versatile_i2c_device = {
+       .name                   = "versatile-i2c",
+       .id                     = -1,
+       .num_resources          = 1,
+       .resource               = &versatile_i2c_resource,
+};
+
 #define VERSATILE_SYSMCI       (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_MCI_OFFSET)
 
 unsigned int mmc_status(struct device *dev)
@@ -769,6 +789,7 @@ void __init versatile_init(void)
        clk_register(&versatile_clcd_clk);
 
        platform_device_register(&versatile_flash_device);
+       platform_device_register(&versatile_i2c_device);
        platform_device_register(&smc91x_device);
 
        for (i = 0; i < ARRAY_SIZE(amba_devs); i++) {
@@ -808,46 +829,6 @@ void __init versatile_init(void)
 #define TICKS2USECS(x) ((x) / TICKS_PER_uSEC)
 #endif
 
-/*
- * Returns number of ms since last clock interrupt.  Note that interrupts
- * will have been disabled by do_gettimeoffset()
- */
-static unsigned long versatile_gettimeoffset(void)
-{
-       unsigned long ticks1, ticks2, status;
-
-       /*
-        * Get the current number of ticks.  Note that there is a race
-        * condition between us reading the timer and checking for
-        * an interrupt.  We get around this by ensuring that the
-        * counter has not reloaded between our two reads.
-        */
-       ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff;
-       do {
-               ticks1 = ticks2;
-               status = __raw_readl(VA_IC_BASE + VIC_RAW_STATUS);
-               ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff;
-       } while (ticks2 > ticks1);
-
-       /*
-        * Number of ticks since last interrupt.
-        */
-       ticks1 = TIMER_RELOAD - ticks2;
-
-       /*
-        * Interrupt pending?  If so, we've reloaded once already.
-        *
-        * FIXME: Need to check this is effectively timer 0 that expires
-        */
-       if (status & IRQMASK_TIMERINT0_1)
-               ticks1 += TIMER_RELOAD;
-
-       /*
-        * Convert the ticks to usecs
-        */
-       return TICKS2USECS(ticks1);
-}
-
 /*
  * IRQ handler for the timer
  */
@@ -871,6 +852,36 @@ static struct irqaction versatile_timer_irq = {
        .handler        = versatile_timer_interrupt,
 };
 
+static cycle_t versatile_get_cycles(void)
+{
+       return ~readl(TIMER3_VA_BASE + TIMER_VALUE);
+}
+
+static struct clocksource clocksource_versatile = {
+       .name           = "timer3",
+       .rating         = 200,
+       .read           = versatile_get_cycles,
+       .mask           = CLOCKSOURCE_MASK(32),
+       .shift          = 20,
+       .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init versatile_clocksource_init(void)
+{
+       /* setup timer3 as free-running clocksource */
+       writel(0, TIMER3_VA_BASE + TIMER_CTRL);
+       writel(0xffffffff, TIMER3_VA_BASE + TIMER_LOAD);
+       writel(0xffffffff, TIMER3_VA_BASE + TIMER_VALUE);
+       writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
+              TIMER3_VA_BASE + TIMER_CTRL);
+
+       clocksource_versatile.mult =
+               clocksource_khz2mult(1000, clocksource_versatile.shift);
+       clocksource_register(&clocksource_versatile);
+
+       return 0;
+}
+
 /*
  * Set up timer interrupt, and return the current time in seconds.
  */
@@ -907,9 +918,11 @@ static void __init versatile_timer_init(void)
         * Make irqs happen for the system timer
         */
        setup_irq(IRQ_TIMERINT0_1, &versatile_timer_irq);
+
+       versatile_clocksource_init();
 }
 
 struct sys_timer versatile_timer = {
        .init           = versatile_timer_init,
-       .offset         = versatile_gettimeoffset,
 };
+