lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[PATCH] ARM: Convert ARM timer implementations to use readl/writel

Browse Source 
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 <rmk+kernel@arm.linux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Russell King
2005-06-29 15:15:54 +01:00
committed by Russell King
parent 6904b2465c
commit b720f73296
3 changed files with 58 additions and 64 deletions
Download Patch File Download Diff File Expand all files Collapse all files

42
arch/arm/mach-integrator/core.c
View File

@@ -20,6 +20,7 @@
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/hardware/amba.h>
#include <asm/hardware/arm_timer.h>
#include <asm/arch/cm.h>
#include <asm/system.h>
#include <asm/leds.h>
@@ -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