diff options
Diffstat (limited to 'arch/mips/au1000/common/time.c')
| -rw-r--r-- | arch/mips/au1000/common/time.c | 78 | 
1 files changed, 35 insertions, 43 deletions
diff --git a/arch/mips/au1000/common/time.c b/arch/mips/au1000/common/time.c index bdb6d73b26f..563d9390a87 100644 --- a/arch/mips/au1000/common/time.c +++ b/arch/mips/au1000/common/time.c @@ -25,11 +25,9 @@   *   * Setting up the clock on the MIPS boards.   * - * Update.  Always configure the kernel with CONFIG_NEW_TIME_C.  This - * will use the user interface gettimeofday() functions from the - * arch/mips/kernel/time.c, and we provide the clock interrupt processing - * and the timer offset compute functions.  If CONFIG_PM is selected, - * we also ensure the 32KHz timer is available.   -- Dan + * We provide the clock interrupt processing and the timer offset compute + * functions.  If CONFIG_PM is selected, we also ensure the 32KHz timer is + * available.  -- Dan   */  #include <linux/types.h> @@ -47,8 +45,7 @@ extern int allow_au1k_wait; /* default off for CP0 Counter */  #if HZ < 100 || HZ > 1000  #error "unsupported HZ value! Must be in [100,1000]"  #endif -#define MATCH20_INC (328*100/HZ) /* magic number 328 is for HZ=100... */ -extern void startup_match20_interrupt(irq_handler_t handler); +#define MATCH20_INC (328 * 100 / HZ) /* magic number 328 is for HZ=100... */  static unsigned long last_pc0, last_match20;  #endif @@ -61,7 +58,7 @@ static irqreturn_t counter0_irq(int irq, void *dev_id)  {  	unsigned long pc0;  	int time_elapsed; -	static int jiffie_drift = 0; +	static int jiffie_drift;  	if (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20) {  		/* should never happen! */ @@ -70,13 +67,11 @@ static irqreturn_t counter0_irq(int irq, void *dev_id)  	}  	pc0 = au_readl(SYS_TOYREAD); -	if (pc0 < last_match20) { +	if (pc0 < last_match20)  		/* counter overflowed */  		time_elapsed = (0xffffffff - last_match20) + pc0; -	} -	else { +	else  		time_elapsed = pc0 - last_match20; -	}  	while (time_elapsed > 0) {  		do_timer(1); @@ -92,8 +87,9 @@ static irqreturn_t counter0_irq(int irq, void *dev_id)  	au_writel(last_match20 + MATCH20_INC, SYS_TOYMATCH2);  	au_sync(); -	/* our counter ticks at 10.009765625 ms/tick, we we're running -	 * almost 10uS too slow per tick. +	/* +	 * Our counter ticks at 10.009765625 ms/tick, we we're running +	 * almost 10 uS too slow per tick.  	 */  	if (jiffie_drift >= 999) { @@ -117,20 +113,17 @@ struct irqaction counter0_action = {  /* When we wakeup from sleep, we have to "catch up" on all of the   * timer ticks we have missed.   */ -void -wakeup_counter0_adjust(void) +void wakeup_counter0_adjust(void)  {  	unsigned long pc0;  	int time_elapsed;  	pc0 = au_readl(SYS_TOYREAD); -	if (pc0 < last_match20) { +	if (pc0 < last_match20)  		/* counter overflowed */  		time_elapsed = (0xffffffff - last_match20) + pc0; -	} -	else { +	else  		time_elapsed = pc0 - last_match20; -	}  	while (time_elapsed > 0) {  		time_elapsed -= MATCH20_INC; @@ -143,10 +136,8 @@ wakeup_counter0_adjust(void)  } -/* This is just for debugging to set the timer for a sleep delay. -*/ -void -wakeup_counter0_set(int ticks) +/* This is just for debugging to set the timer for a sleep delay. */ +void wakeup_counter0_set(int ticks)  {  	unsigned long pc0; @@ -157,21 +148,22 @@ wakeup_counter0_set(int ticks)  }  #endif -/* I haven't found anyone that doesn't use a 12 MHz source clock, +/* + * I haven't found anyone that doesn't use a 12 MHz source clock,   * but just in case.....   */  #define AU1000_SRC_CLK	12000000  /*   * We read the real processor speed from the PLL.  This is important - * because it is more accurate than computing it from the 32KHz + * because it is more accurate than computing it from the 32 KHz   * counter, if it exists.  If we don't have an accurate processor   * speed, all of the peripherals that derive their clocks based on   * this advertised speed will introduce error and sometimes not work   * properly.  This function is futher convoluted to still allow configurations   * to do that in case they have really, really old silicon with a - * write-only PLL register, that we need the 32KHz when power management - * "wait" is enabled, and we need to detect if the 32KHz isn't present + * write-only PLL register, that we need the 32 KHz when power management + * "wait" is enabled, and we need to detect if the 32 KHz isn't present   * but requested......got it? :-)		-- Dan   */  unsigned long calc_clock(void) @@ -182,8 +174,7 @@ unsigned long calc_clock(void)  	spin_lock_irqsave(&time_lock, flags); -	/* Power management cares if we don't have a 32KHz counter. -	*/ +	/* Power management cares if we don't have a 32 KHz counter. */  	no_au1xxx_32khz = 0;  	counter = au_readl(SYS_COUNTER_CNTRL);  	if (counter & SYS_CNTRL_E0) { @@ -193,7 +184,7 @@ unsigned long calc_clock(void)  		while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_T1S);  		/* RTC now ticks at 32.768/16 kHz */ -		au_writel(trim_divide-1, SYS_RTCTRIM); +		au_writel(trim_divide - 1, SYS_RTCTRIM);  		while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_T1S);  		while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C1S); @@ -215,9 +206,11 @@ unsigned long calc_clock(void)  #endif  	else  		cpu_speed = (au_readl(SYS_CPUPLL) & 0x0000003f) * AU1000_SRC_CLK; +	/* On Alchemy CPU:counter ratio is 1:1 */  	mips_hpt_frequency = cpu_speed; -	// Equation: Baudrate = CPU / (SD * 2 * CLKDIV * 16) -	set_au1x00_uart_baud_base(cpu_speed / (2 * ((int)(au_readl(SYS_POWERCTRL)&0x03) + 2) * 16)); +	/* Equation: Baudrate = CPU / (SD * 2 * CLKDIV * 16) */ +	set_au1x00_uart_baud_base(cpu_speed / (2 * ((int)(au_readl(SYS_POWERCTRL) +							  & 0x03) + 2) * 16));  	spin_unlock_irqrestore(&time_lock, flags);  	return cpu_speed;  } @@ -228,10 +221,10 @@ void __init plat_time_init(void)  	est_freq += 5000;    /* round */  	est_freq -= est_freq%10000; -	printk("CPU frequency %d.%02d MHz\n", est_freq/1000000, -	       (est_freq%1000000)*100/1000000); - 	set_au1x00_speed(est_freq); - 	set_au1x00_lcd_clock(); // program the LCD clock +	printk(KERN_INFO "CPU frequency %u.%02u MHz\n", +	       est_freq / 1000000, ((est_freq % 1000000) * 100) / 1000000); +	set_au1x00_speed(est_freq); +	set_au1x00_lcd_clock(); /* program the LCD clock */  #ifdef CONFIG_PM  	/* @@ -243,30 +236,29 @@ void __init plat_time_init(void)  	 * counter 0 interrupt as a special irq and it doesn't show  	 * up under /proc/interrupts.  	 * -	 * Check to ensure we really have a 32KHz oscillator before +	 * Check to ensure we really have a 32 KHz oscillator before  	 * we do this.  	 */  	if (no_au1xxx_32khz) -		printk("WARNING: no 32KHz clock found.\n"); +		printk(KERN_WARNING "WARNING: no 32KHz clock found.\n");  	else {  		while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C0S);  		au_writel(0, SYS_TOYWRITE);  		while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_C0S); -		au_writel(au_readl(SYS_WAKEMSK) | (1<<8), SYS_WAKEMSK); +		au_writel(au_readl(SYS_WAKEMSK) | (1 << 8), SYS_WAKEMSK);  		au_writel(~0, SYS_WAKESRC);  		au_sync();  		while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20); -		/* setup match20 to interrupt once every HZ */ +		/* Setup match20 to interrupt once every HZ */  		last_pc0 = last_match20 = au_readl(SYS_TOYREAD);  		au_writel(last_match20 + MATCH20_INC, SYS_TOYMATCH2);  		au_sync();  		while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20);  		setup_irq(AU1000_TOY_MATCH2_INT, &counter0_action); -		/* We can use the real 'wait' instruction. -		*/ +		/* We can use the real 'wait' instruction. */  		allow_au1k_wait = 1;  	}  |