From b720f73296916e87c744193c57bc8687d35888fe Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 29 Jun 2005 15:15:54 +0100 Subject: [PATCH] [PATCH] ARM: Convert ARM timer implementations to use readl/writel Convert ARMs timer implementations to use readl/writel instead of accessing the registers via a struct. People have recently asked if accessing timers via a structure is the "right way" and its not the Linux way. So fix this code to conform to "The Linux Way"(tm). Signed-off-by: Russell King Acked-by: Catalin Marinas --- arch/arm/mach-integrator/core.c | 42 +++++++------------ arch/arm/mach-versatile/core.c | 61 +++++++++++----------------- include/asm-arm/hardware/arm_timer.h | 21 ++++++++++ 3 files changed, 59 insertions(+), 65 deletions(-) create mode 100644 include/asm-arm/hardware/arm_timer.h diff --git a/arch/arm/mach-integrator/core.c b/arch/arm/mach-integrator/core.c index 9222e57bd872..797c7fddaa0d 100644 --- a/arch/arm/mach-integrator/core.c +++ b/arch/arm/mach-integrator/core.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -156,16 +157,6 @@ EXPORT_SYMBOL(cm_control); #define TICKS2USECS(x) ((x) / TICKS_PER_uSEC) #endif -/* - * What does it look like? - */ -typedef struct TimerStruct { - unsigned long TimerLoad; - unsigned long TimerValue; - unsigned long TimerControl; - unsigned long TimerClear; -} TimerStruct_t; - static unsigned long timer_reload; /* @@ -174,7 +165,6 @@ static unsigned long timer_reload; */ unsigned long integrator_gettimeoffset(void) { - volatile TimerStruct_t *timer1 = (TimerStruct_t *)TIMER1_VA_BASE; unsigned long ticks1, ticks2, status; /* @@ -183,11 +173,11 @@ unsigned long integrator_gettimeoffset(void) * an interrupt. We get around this by ensuring that the * counter has not reloaded between our two reads. */ - ticks2 = timer1->TimerValue & 0xffff; + ticks2 = readl(TIMER1_VA_BASE + TIMER_VALUE) & 0xffff; do { ticks1 = ticks2; status = __raw_readl(VA_IC_BASE + IRQ_RAW_STATUS); - ticks2 = timer1->TimerValue & 0xffff; + ticks2 = readl(TIMER1_VA_BASE + TIMER_VALUE) & 0xffff; } while (ticks2 > ticks1); /* @@ -213,20 +203,19 @@ unsigned long integrator_gettimeoffset(void) static irqreturn_t integrator_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) { - volatile TimerStruct_t *timer1 = (volatile TimerStruct_t *)TIMER1_VA_BASE; - write_seqlock(&xtime_lock); /* * clear the interrupt */ - timer1->TimerClear = 1; + writel(1, TIMER1_VA_BASE + TIMER_INTCLR); /* * the clock tick routines are only processed on the * primary CPU */ if (hard_smp_processor_id() == 0) { + nmi_tick(); timer_tick(regs); #ifdef CONFIG_SMP smp_send_timer(); @@ -256,32 +245,29 @@ static struct irqaction integrator_timer_irq = { */ void __init integrator_time_init(unsigned long reload, unsigned int ctrl) { - volatile TimerStruct_t *timer0 = (volatile TimerStruct_t *)TIMER0_VA_BASE; - volatile TimerStruct_t *timer1 = (volatile TimerStruct_t *)TIMER1_VA_BASE; - volatile TimerStruct_t *timer2 = (volatile TimerStruct_t *)TIMER2_VA_BASE; - unsigned int timer_ctrl = 0x80 | 0x40; /* periodic */ + unsigned int timer_ctrl = TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC; timer_reload = reload; timer_ctrl |= ctrl; if (timer_reload > 0x100000) { timer_reload >>= 8; - timer_ctrl |= 0x08; /* /256 */ + timer_ctrl |= TIMER_CTRL_DIV256; } else if (timer_reload > 0x010000) { timer_reload >>= 4; - timer_ctrl |= 0x04; /* /16 */ + timer_ctrl |= TIMER_CTRL_DIV16; } /* * Initialise to a known state (all timers off) */ - timer0->TimerControl = 0; - timer1->TimerControl = 0; - timer2->TimerControl = 0; + writel(0, TIMER0_VA_BASE + TIMER_CTRL); + writel(0, TIMER1_VA_BASE + TIMER_CTRL); + writel(0, TIMER2_VA_BASE + TIMER_CTRL); - timer1->TimerLoad = timer_reload; - timer1->TimerValue = timer_reload; - timer1->TimerControl = timer_ctrl; + writel(timer_reload, TIMER1_VA_BASE + TIMER_LOAD); + writel(timer_reload, TIMER1_VA_BASE + TIMER_VALUE); + writel(timer_ctrl, TIMER1_VA_BASE + TIMER_CTRL); /* * Make irqs happen for the system timer diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c index 9d1f2253e987..f01c0f8a2bb3 100644 --- a/arch/arm/mach-versatile/core.c +++ b/arch/arm/mach-versatile/core.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -788,38 +789,25 @@ void __init versatile_init(void) */ #define TIMER_INTERVAL (TICKS_PER_uSEC * mSEC_10) #if TIMER_INTERVAL >= 0x100000 -#define TIMER_RELOAD (TIMER_INTERVAL >> 8) /* Divide by 256 */ -#define TIMER_CTRL 0x88 /* Enable, Clock / 256 */ +#define TIMER_RELOAD (TIMER_INTERVAL >> 8) +#define TIMER_DIVISOR (TIMER_CTRL_DIV256) #define TICKS2USECS(x) (256 * (x) / TICKS_PER_uSEC) #elif TIMER_INTERVAL >= 0x10000 #define TIMER_RELOAD (TIMER_INTERVAL >> 4) /* Divide by 16 */ -#define TIMER_CTRL 0x84 /* Enable, Clock / 16 */ +#define TIMER_DIVISOR (TIMER_CTRL_DIV16) #define TICKS2USECS(x) (16 * (x) / TICKS_PER_uSEC) #else #define TIMER_RELOAD (TIMER_INTERVAL) -#define TIMER_CTRL 0x80 /* Enable */ +#define TIMER_DIVISOR (TIMER_CTRL_DIV1) #define TICKS2USECS(x) ((x) / TICKS_PER_uSEC) #endif -#define TIMER_CTRL_IE (1 << 5) /* Interrupt Enable */ - -/* - * What does it look like? - */ -typedef struct TimerStruct { - unsigned long TimerLoad; - unsigned long TimerValue; - unsigned long TimerControl; - unsigned long TimerClear; -} TimerStruct_t; - /* * Returns number of ms since last clock interrupt. Note that interrupts * will have been disabled by do_gettimeoffset() */ static unsigned long versatile_gettimeoffset(void) { - volatile TimerStruct_t *timer0 = (TimerStruct_t *)TIMER0_VA_BASE; unsigned long ticks1, ticks2, status; /* @@ -828,11 +816,11 @@ static unsigned long versatile_gettimeoffset(void) * an interrupt. We get around this by ensuring that the * counter has not reloaded between our two reads. */ - ticks2 = timer0->TimerValue & 0xffff; + ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff; do { ticks1 = ticks2; status = __raw_readl(VA_IC_BASE + VIC_IRQ_RAW_STATUS); - ticks2 = timer0->TimerValue & 0xffff; + ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff; } while (ticks2 > ticks1); /* @@ -859,12 +847,10 @@ static unsigned long versatile_gettimeoffset(void) */ static irqreturn_t versatile_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) { - volatile TimerStruct_t *timer0 = (volatile TimerStruct_t *)TIMER0_VA_BASE; - write_seqlock(&xtime_lock); // ...clear the interrupt - timer0->TimerClear = 1; + writel(1, TIMER0_VA_BASE + TIMER_INTCLR); timer_tick(regs); @@ -884,31 +870,32 @@ static struct irqaction versatile_timer_irq = { */ static void __init versatile_timer_init(void) { - volatile TimerStruct_t *timer0 = (volatile TimerStruct_t *)TIMER0_VA_BASE; - volatile TimerStruct_t *timer1 = (volatile TimerStruct_t *)TIMER1_VA_BASE; - volatile TimerStruct_t *timer2 = (volatile TimerStruct_t *)TIMER2_VA_BASE; - volatile TimerStruct_t *timer3 = (volatile TimerStruct_t *)TIMER3_VA_BASE; + u32 val; /* * set clock frequency: * VERSATILE_REFCLK is 32KHz * VERSATILE_TIMCLK is 1MHz */ - *(volatile unsigned int *)IO_ADDRESS(VERSATILE_SCTL_BASE) |= - ((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) | (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) | - (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) | (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel)); + val = readl(IO_ADDRESS(VERSATILE_SCTL_BASE)); + writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) | + (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) | + (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) | + (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val, + IO_ADDRESS(VERSATILE_SCTL_BASE)); /* * Initialise to a known state (all timers off) */ - timer0->TimerControl = 0; - timer1->TimerControl = 0; - timer2->TimerControl = 0; - timer3->TimerControl = 0; - - timer0->TimerLoad = TIMER_RELOAD; - timer0->TimerValue = TIMER_RELOAD; - timer0->TimerControl = TIMER_CTRL | 0x40 | TIMER_CTRL_IE; /* periodic + IE */ + writel(0, TIMER0_VA_BASE + TIMER_CTRL); + writel(0, TIMER1_VA_BASE + TIMER_CTRL); + writel(0, TIMER2_VA_BASE + TIMER_CTRL); + writel(0, TIMER3_VA_BASE + TIMER_CTRL); + + writel(TIMER_RELOAD, TIMER0_VA_BASE + TIMER_LOAD); + writel(TIMER_RELOAD, TIMER0_VA_BASE + TIMER_VALUE); + writel(TIMER_DIVISOR | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC | + TIMER_CTRL_IE, TIMER0_VA_BASE + TIMER_CTRL); /* * Make irqs happen for the system timer diff --git a/include/asm-arm/hardware/arm_timer.h b/include/asm-arm/hardware/arm_timer.h new file mode 100644 index 000000000000..04be3bdf46b8 --- /dev/null +++ b/include/asm-arm/hardware/arm_timer.h @@ -0,0 +1,21 @@ +#ifndef __ASM_ARM_HARDWARE_ARM_TIMER_H +#define __ASM_ARM_HARDWARE_ARM_TIMER_H + +#define TIMER_LOAD 0x00 +#define TIMER_VALUE 0x04 +#define TIMER_CTRL 0x08 +#define TIMER_CTRL_ONESHOT (1 << 0) +#define TIMER_CTRL_32BIT (1 << 1) +#define TIMER_CTRL_DIV1 (0 << 2) +#define TIMER_CTRL_DIV16 (1 << 2) +#define TIMER_CTRL_DIV256 (2 << 2) +#define TIMER_CTRL_IE (1 << 5) /* Interrupt Enable (versatile only) */ +#define TIMER_CTRL_PERIODIC (1 << 6) +#define TIMER_CTRL_ENABLE (1 << 7) + +#define TIMER_INTCLR 0x0c +#define TIMER_RIS 0x10 +#define TIMER_MIS 0x14 +#define TIMER_BGLOAD 0x18 + +#endif -- 2.20.1