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clockevents/drivers/timer-sp804: Migrate to new 'set-state' interface 

Migrate timer-sp driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

There are few more changes worth noticing:

- The clockevent device was disabled by writing: 'TIMER_CTRL_32BIT |
  TIMER_CTRL_IE' to ctrl register earlier. i.e. by un-setting the
  TIMER_CTRL_ENABLE bit. Its done by writing zero now and should have
  the same effect.

- For shutdown and resume we were writing the same value twice to the
  register (to disable the timer), which is fixed now.

- Switching to oneshot mode was divided into two parts earlier:
  - Firstly set_mode() was writing:
    'TIMER_CTRL_32BIT | TIMER_CTRL_IE | TIMER_CTRL_ONESHOT'
    to ctrl register (device not enabled yet)
  - Then sp804_set_next_event() was enabling the device by writing
    'readl(ctrl) | TIMER_CTRL_ENABLE' to the ctrl register. This was
    unnecessarily complicated.
  - Change this to: Stop device on set_state_oneshot and configure it in
    sp804_set_next_event().

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Olof Johansson <olof@lixom.net>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
hifive-unleashed-5.1
Viresh Kumar 2015-07-06 15:39:19 +05:30 committed by Daniel Lezcano
parent 26b91f043a
commit daea72831d
1 changed files with 29 additions and 29 deletions
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58
drivers/clocksource/timer-sp804.c
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@ -133,50 +133,50 @@ static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
static void sp804_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
static inline void timer_shutdown(struct clock_event_device *evt)
{
unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE;
writel(ctrl, clkevt_base + TIMER_CTRL);
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
writel(clkevt_reload, clkevt_base + TIMER_LOAD);
ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
break;
case CLOCK_EVT_MODE_ONESHOT:
/* period set, and timer enabled in 'next_event' hook */
ctrl |= TIMER_CTRL_ONESHOT;
break;
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
default:
break;
}
writel(0, clkevt_base + TIMER_CTRL);
}
static int sp804_shutdown(struct clock_event_device *evt)
{
timer_shutdown(evt);
return 0;
}
static int sp804_set_periodic(struct clock_event_device *evt)
{
unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
timer_shutdown(evt);
writel(clkevt_reload, clkevt_base + TIMER_LOAD);
writel(ctrl, clkevt_base + TIMER_CTRL);
return 0;
}
static int sp804_set_next_event(unsigned long next,
struct clock_event_device *evt)
{
unsigned long ctrl = readl(clkevt_base + TIMER_CTRL);
unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
TIMER_CTRL_ONESHOT | TIMER_CTRL_ENABLE;
writel(next, clkevt_base + TIMER_LOAD);
writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL);
writel(ctrl, clkevt_base + TIMER_CTRL);
return 0;
}
static struct clock_event_device sp804_clockevent = {
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_DYNIRQ,
.set_mode = sp804_set_mode,
.set_next_event = sp804_set_next_event,
.rating = 300,
.features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_DYNIRQ,
.set_state_shutdown = sp804_shutdown,
.set_state_periodic = sp804_set_periodic,
.set_state_oneshot = sp804_shutdown,
.tick_resume = sp804_shutdown,
.set_next_event = sp804_set_next_event,
.rating = 300,
};
static struct irqaction sp804_timer_irq = {