#include <asm/mach/time.h>
#include <asm/sched_clock.h>
-#include <plat/mtu.h>
+/*
+ * Guaranteed runtime conversion range in seconds for
+ * the clocksource and clockevent.
+ */
+#define MTU_MIN_RANGE 4
+
+/*
+ * The MTU device hosts four different counters, with 4 set of
+ * registers. These are register names.
+ */
+
+#define MTU_IMSC 0x00 /* Interrupt mask set/clear */
+#define MTU_RIS 0x04 /* Raw interrupt status */
+#define MTU_MIS 0x08 /* Masked interrupt status */
+#define MTU_ICR 0x0C /* Interrupt clear register */
+
+/* per-timer registers take 0..3 as argument */
+#define MTU_LR(x) (0x10 + 0x10 * (x) + 0x00) /* Load value */
+#define MTU_VAL(x) (0x10 + 0x10 * (x) + 0x04) /* Current value */
+#define MTU_CR(x) (0x10 + 0x10 * (x) + 0x08) /* Control reg */
+#define MTU_BGLR(x) (0x10 + 0x10 * (x) + 0x0c) /* At next overflow */
+
+/* bits for the control register */
+#define MTU_CRn_ENA 0x80
+#define MTU_CRn_PERIODIC 0x40 /* if 0 = free-running */
+#define MTU_CRn_PRESCALE_MASK 0x0c
+#define MTU_CRn_PRESCALE_1 0x00
+#define MTU_CRn_PRESCALE_16 0x04
+#define MTU_CRn_PRESCALE_256 0x08
+#define MTU_CRn_32BITS 0x02
+#define MTU_CRn_ONESHOT 0x01 /* if 0 = wraps reloading from BGLR*/
+
+/* Other registers are usual amba/primecell registers, currently not used */
+#define MTU_ITCR 0xff0
+#define MTU_ITOP 0xff4
+
+#define MTU_PERIPH_ID0 0xfe0
+#define MTU_PERIPH_ID1 0xfe4
+#define MTU_PERIPH_ID2 0xfe8
+#define MTU_PERIPH_ID3 0xfeC
+
+#define MTU_PCELL0 0xff0
+#define MTU_PCELL1 0xff4
+#define MTU_PCELL2 0xff8
+#define MTU_PCELL3 0xffC
+
+static bool clkevt_periodic;
+static u32 clk_prescale;
+static u32 nmdk_cycle; /* write-once */
void __iomem *mtu_base; /* Assigned by machine code */
+
#ifdef CONFIG_NOMADIK_MTU_SCHED_CLOCK
/*
* Override the global weak sched_clock symbol with this
update_sched_clock(&cd, cyc, (u32)~0);
}
#endif
+
/* Clockevent device: use one-shot mode */
+static int nmdk_clkevt_next(unsigned long evt, struct clock_event_device *ev)
+{
+ writel(1 << 1, mtu_base + MTU_IMSC);
+ writel(evt, mtu_base + MTU_LR(1));
+ /* Load highest value, enable device, enable interrupts */
+ writel(MTU_CRn_ONESHOT | clk_prescale |
+ MTU_CRn_32BITS | MTU_CRn_ENA,
+ mtu_base + MTU_CR(1));
+
+ return 0;
+}
+
+void nmdk_clkevt_reset(void)
+{
+ if (clkevt_periodic) {
+
+ /* Timer: configure load and background-load, and fire it up */
+ writel(nmdk_cycle, mtu_base + MTU_LR(1));
+ writel(nmdk_cycle, mtu_base + MTU_BGLR(1));
+
+ writel(MTU_CRn_PERIODIC | clk_prescale |
+ MTU_CRn_32BITS | MTU_CRn_ENA,
+ mtu_base + MTU_CR(1));
+ writel(1 << 1, mtu_base + MTU_IMSC);
+ } else {
+ /* Generate an interrupt to start the clockevent again */
+ (void) nmdk_clkevt_next(nmdk_cycle, NULL);
+ }
+}
+
static void nmdk_clkevt_mode(enum clock_event_mode mode,
struct clock_event_device *dev)
{
- u32 cr;
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
- pr_err("%s: periodic mode not supported\n", __func__);
+ clkevt_periodic = true;
+ nmdk_clkevt_reset();
break;
case CLOCK_EVT_MODE_ONESHOT:
- /* Load highest value, enable device, enable interrupts */
- cr = readl(mtu_base + MTU_CR(1));
- writel(0, mtu_base + MTU_LR(1));
- writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(1));
- writel(1 << 1, mtu_base + MTU_IMSC);
+ clkevt_periodic = false;
break;
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_UNUSED:
- /* disable irq */
writel(0, mtu_base + MTU_IMSC);
/* disable timer */
- cr = readl(mtu_base + MTU_CR(1));
- cr &= ~MTU_CRn_ENA;
- writel(cr, mtu_base + MTU_CR(1));
+ writel(0, mtu_base + MTU_CR(1));
/* load some high default value */
writel(0xffffffff, mtu_base + MTU_LR(1));
break;
}
}
-static int nmdk_clkevt_next(unsigned long evt, struct clock_event_device *ev)
-{
- /* writing the value has immediate effect */
- writel(evt, mtu_base + MTU_LR(1));
- return 0;
-}
-
static struct clock_event_device nmdk_clkevt = {
.name = "mtu_1",
- .features = CLOCK_EVT_FEAT_ONESHOT,
+ .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
.rating = 200,
.set_mode = nmdk_clkevt_mode,
.set_next_event = nmdk_clkevt_next,
.dev_id = &nmdk_clkevt,
};
+void nmdk_clksrc_reset(void)
+{
+ /* Disable */
+ writel(0, mtu_base + MTU_CR(0));
+
+ /* ClockSource: configure load and background-load, and fire it up */
+ writel(nmdk_cycle, mtu_base + MTU_LR(0));
+ writel(nmdk_cycle, mtu_base + MTU_BGLR(0));
+
+ writel(clk_prescale | MTU_CRn_32BITS | MTU_CRn_ENA,
+ mtu_base + MTU_CR(0));
+}
+
void __init nmdk_timer_init(void)
{
unsigned long rate;
struct clk *clk0;
- u32 cr = MTU_CRn_32BITS;
clk0 = clk_get_sys("mtu0", NULL);
BUG_ON(IS_ERR(clk0));
rate = clk_get_rate(clk0);
if (rate > 32000000) {
rate /= 16;
- cr |= MTU_CRn_PRESCALE_16;
+ clk_prescale = MTU_CRn_PRESCALE_16;
} else {
- cr |= MTU_CRn_PRESCALE_1;
+ clk_prescale = MTU_CRn_PRESCALE_1;
}
+ nmdk_cycle = (rate + HZ/2) / HZ;
+
+
/* Timer 0 is the free running clocksource */
- writel(cr, mtu_base + MTU_CR(0));
- writel(0, mtu_base + MTU_LR(0));
- writel(0, mtu_base + MTU_BGLR(0));
- writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(0));
+ nmdk_clksrc_reset();
if (clocksource_mmio_init(mtu_base + MTU_VAL(0), "mtu_0",
rate, 200, 32, clocksource_mmio_readl_down))
clockevents_calc_mult_shift(&nmdk_clkevt, rate, MTU_MIN_RANGE);
- writel(cr | MTU_CRn_ONESHOT, mtu_base + MTU_CR(1)); /* off, currently */
-
nmdk_clkevt.max_delta_ns =
clockevent_delta2ns(0xffffffff, &nmdk_clkevt);
nmdk_clkevt.min_delta_ns =
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