static void __init lpc32xx_timer_init(void)
{
u32 clkrate, pllreg;
__raw_writel(LPC32XX_CLKPWR_TMRPWMCLK_TIMER0_EN |
LPC32XX_CLKPWR_TMRPWMCLK_TIMER1_EN,
LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1);
if (clk_is_sysclk_mainosc() != 0)
clkrate = LPC32XX_MAIN_OSC_FREQ;
else
clkrate = 397 * LPC32XX_CLOCK_OSC_FREQ;
pllreg = __raw_readl(LPC32XX_CLKPWR_HCLKPLL_CTRL) & 0x1FFFF;
clkrate = clk_get_pllrate_from_reg(clkrate, pllreg);
clkrate = clkrate / clk_get_pclk_div();
__raw_writel(0, LPC32XX_TIMER_TCR(LPC32XX_TIMER0_BASE));
__raw_writel(LPC32XX_TIMER_CNTR_MTCH_BIT(0),
LPC32XX_TIMER_IR(LPC32XX_TIMER0_BASE));
__raw_writel(1, LPC32XX_TIMER_MR0(LPC32XX_TIMER0_BASE));
__raw_writel(LPC32XX_TIMER_CNTR_MCR_MTCH(0) |
LPC32XX_TIMER_CNTR_MCR_STOP(0) |
LPC32XX_TIMER_CNTR_MCR_RESET(0),
LPC32XX_TIMER_MCR(LPC32XX_TIMER0_BASE));
setup_irq(IRQ_LPC32XX_TIMER0, &lpc32xx_timer_irq);
lpc32xx_clkevt.mult = div_sc(clkrate, NSEC_PER_SEC,
lpc32xx_clkevt.shift);
lpc32xx_clkevt.max_delta_ns = clockevent_delta2ns(-1,
&lpc32xx_clkevt);
lpc32xx_clkevt.min_delta_ns = clockevent_delta2ns(1,
&lpc32xx_clkevt) + 1;
lpc32xx_clkevt.cpumask = cpumask_of(0);
clockevents_register_device(&lpc32xx_clkevt);
__raw_writel(LPC32XX_TIMER_CNTR_TCR_RESET,
LPC32XX_TIMER_TCR(LPC32XX_TIMER1_BASE));
__raw_writel(0, LPC32XX_TIMER_PR(LPC32XX_TIMER1_BASE));
__raw_writel(0, LPC32XX_TIMER_MCR(LPC32XX_TIMER1_BASE));
__raw_writel(LPC32XX_TIMER_CNTR_TCR_EN,
LPC32XX_TIMER_TCR(LPC32XX_TIMER1_BASE));
clocksource_mmio_init(LPC32XX_TIMER_TC(LPC32XX_TIMER1_BASE),
"lpc32xx_clksrc", clkrate, 300, 32, clocksource_mmio_readl_up);
}
/*
* The clock management driver isn't initialized at this point, so the
* clocks need to be enabled here manually and then tagged as used in
* the clock driver initialization
*/
void __init lpc32xx_timer_init(void)
{
u32 clkrate, pllreg;
/* Enable timer clock */
__raw_writel(LPC32XX_CLKPWR_TMRPWMCLK_TIMER0_EN |
LPC32XX_CLKPWR_TMRPWMCLK_TIMER1_EN,
LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1);
/*
* The clock driver isn't initialized at this point. So determine if
* the SYSCLK is driven from the PLL397 or main oscillator and then use
* it to compute the PLL frequency and the PCLK divider to get the base
* timer rates. This rate is needed to compute the tick rate.
*/
if (clk_is_sysclk_mainosc() != 0)
clkrate = LPC32XX_MAIN_OSC_FREQ;
else
clkrate = 397 * LPC32XX_CLOCK_OSC_FREQ;
/* Get ARM HCLKPLL register and convert it into a frequency */
pllreg = __raw_readl(LPC32XX_CLKPWR_HCLKPLL_CTRL) & 0x1FFFF;
clkrate = clk_get_pllrate_from_reg(clkrate, pllreg);
/* Get PCLK divider and divide ARM PLL clock by it to get timer rate */
clkrate = clkrate / clk_get_pclk_div();
/* Initial timer setup */
__raw_writel(0, LPC32XX_TIMER_TCR(LPC32XX_TIMER0_BASE));
__raw_writel(LPC32XX_TIMER_CNTR_MTCH_BIT(0),
LPC32XX_TIMER_IR(LPC32XX_TIMER0_BASE));
__raw_writel(1, LPC32XX_TIMER_MR0(LPC32XX_TIMER0_BASE));
__raw_writel(LPC32XX_TIMER_CNTR_MCR_MTCH(0) |
LPC32XX_TIMER_CNTR_MCR_STOP(0) |
LPC32XX_TIMER_CNTR_MCR_RESET(0),
LPC32XX_TIMER_MCR(LPC32XX_TIMER0_BASE));
/* Setup tick interrupt */
setup_irq(IRQ_LPC32XX_TIMER0, &lpc32xx_timer_irq);
/* Setup the clockevent structure. */
lpc32xx_clkevt.cpumask = cpumask_of(0);
clockevents_config_and_register(&lpc32xx_clkevt, clkrate, 1, -1);
/* Use timer1 as clock source. */
__raw_writel(LPC32XX_TIMER_CNTR_TCR_RESET,
LPC32XX_TIMER_TCR(LPC32XX_TIMER1_BASE));
__raw_writel(0, LPC32XX_TIMER_PR(LPC32XX_TIMER1_BASE));
__raw_writel(0, LPC32XX_TIMER_MCR(LPC32XX_TIMER1_BASE));
__raw_writel(LPC32XX_TIMER_CNTR_TCR_EN,
LPC32XX_TIMER_TCR(LPC32XX_TIMER1_BASE));
clocksource_mmio_init(LPC32XX_TIMER_TC(LPC32XX_TIMER1_BASE),
"lpc32xx_clksrc", clkrate, 300, 32, clocksource_mmio_readl_up);
}
static irqreturn_t lpc32xx_timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = &lpc32xx_clkevt;
__raw_writel(LPC32XX_TIMER_CNTR_MTCH_BIT(0),
LPC32XX_TIMER_IR(LPC32XX_TIMER0_BASE));
evt->event_handler(evt);
return IRQ_HANDLED;
}