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    Subject[RFC PATCH v2 13/14] m68k: mvme16x: Convert to clocksource API
    Date
    Add a platform clocksource by adapting the existing arch_gettimeoffset
    implementation.

    Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
    Acked-by: Linus Walleij <linus.walleij@linaro.org>
    ---
    Changed since v1:
    - Moved clk_total access to within the irq lock.
    ---
    arch/m68k/mvme16x/config.c | 39 +++++++++++++++++++++++++++++++-------
    1 file changed, 32 insertions(+), 7 deletions(-)

    diff --git a/arch/m68k/mvme16x/config.c b/arch/m68k/mvme16x/config.c
    index 8bafa6a37593..2c109ee2a1a5 100644
    --- a/arch/m68k/mvme16x/config.c
    +++ b/arch/m68k/mvme16x/config.c
    @@ -19,6 +19,7 @@
    #include <linux/mm.h>
    #include <linux/seq_file.h>
    #include <linux/tty.h>
    +#include <linux/clocksource.h>
    #include <linux/console.h>
    #include <linux/linkage.h>
    #include <linux/init.h>
    @@ -343,6 +344,21 @@ static irqreturn_t mvme16x_abort_int (int irq, void *dev_id)
    return IRQ_HANDLED;
    }

    +static u64 mvme16x_read_clk(struct clocksource *cs);
    +
    +static struct clocksource mvme16x_clk = {
    + .name = "pcc",
    + .rating = 250,
    + .read = mvme16x_read_clk,
    + .mask = CLOCKSOURCE_MASK(32),
    + .flags = CLOCK_SOURCE_IS_CONTINUOUS,
    +};
    +
    +static u32 clk_total;
    +
    +#define PCC_TIMER_CLOCK_FREQ 1000000
    +#define PCC_TIMER_CYCLES (PCC_TIMER_CLOCK_FREQ / HZ)
    +
    static irqreturn_t mvme16x_timer_int (int irq, void *dev_id)
    {
    irq_handler_t timer_routine = dev_id;
    @@ -350,6 +366,7 @@ static irqreturn_t mvme16x_timer_int (int irq, void *dev_id)

    local_irq_save(flags);
    *(volatile unsigned char *)0xfff4201b |= 8;
    + clk_total += PCC_TIMER_CYCLES;
    timer_routine(0, NULL);
    local_irq_restore(flags);

    @@ -363,13 +380,15 @@ void mvme16x_sched_init (irq_handler_t timer_routine)

    /* Using PCCchip2 or MC2 chip tick timer 1 */
    *(volatile unsigned long *)0xfff42008 = 0;
    - *(volatile unsigned long *)0xfff42004 = 10000; /* 10ms */
    + *(volatile unsigned long *)0xfff42004 = PCC_TIMER_CYCLES;
    *(volatile unsigned char *)0xfff42017 |= 3;
    *(volatile unsigned char *)0xfff4201b = 0x16;
    - if (request_irq(MVME16x_IRQ_TIMER, mvme16x_timer_int, 0,
    - "timer", timer_routine))
    + if (request_irq(MVME16x_IRQ_TIMER, mvme16x_timer_int, IRQF_TIMER, "timer",
    + timer_routine))
    panic ("Couldn't register timer int");

    + clocksource_register_hz(&mvme16x_clk, PCC_TIMER_CLOCK_FREQ);
    +
    if (brdno == 0x0162 || brdno == 0x172)
    irq = MVME162_IRQ_ABORT;
    else
    @@ -379,11 +398,17 @@ void mvme16x_sched_init (irq_handler_t timer_routine)
    panic ("Couldn't register abort int");
    }

    -
    -/* This is always executed with interrupts disabled. */
    -u32 mvme16x_gettimeoffset(void)
    +static u64 mvme16x_read_clk(struct clocksource *cs)
    {
    - return (*(volatile u32 *)0xfff42008) * 1000;
    + unsigned long flags;
    + u32 ticks;
    +
    + local_irq_save(flags);
    + ticks = *(volatile u32 *)0xfff42008;
    + ticks += clk_total;
    + local_irq_restore(flags);
    +
    + return ticks;
    }

    int bcd2int (unsigned char b)
    --
    2.18.1
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