Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/mach-footbridge/dc21285-timer.c |
| 3 | * |
| 4 | * Copyright (C) 1998 Russell King. |
| 5 | * Copyright (C) 1998 Phil Blundell |
| 6 | */ |
| 7 | #include <linux/init.h> |
| 8 | #include <linux/interrupt.h> |
Thomas Gleixner | 55e8698 | 2006-07-01 22:32:17 +0100 | [diff] [blame] | 9 | #include <linux/irq.h> |
Russell King | 70d13e0 | 2008-12-06 08:25:16 +0000 | [diff] [blame] | 10 | #include <linux/spinlock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | |
| 12 | #include <asm/irq.h> |
| 13 | |
| 14 | #include <asm/hardware/dec21285.h> |
| 15 | #include <asm/mach/time.h> |
| 16 | |
| 17 | #include "common.h" |
| 18 | |
| 19 | /* |
| 20 | * Footbridge timer 1 support. |
| 21 | */ |
| 22 | static unsigned long timer1_latch; |
| 23 | |
| 24 | static unsigned long timer1_gettimeoffset (void) |
| 25 | { |
| 26 | unsigned long value = timer1_latch - *CSR_TIMER1_VALUE; |
| 27 | |
| 28 | return ((tick_nsec / 1000) * value) / timer1_latch; |
| 29 | } |
| 30 | |
| 31 | static irqreturn_t |
Linus Torvalds | 0cd61b6 | 2006-10-06 10:53:39 -0700 | [diff] [blame] | 32 | timer1_interrupt(int irq, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | *CSR_TIMER1_CLR = 0; |
| 35 | |
Linus Torvalds | 0cd61b6 | 2006-10-06 10:53:39 -0700 | [diff] [blame] | 36 | timer_tick(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | return IRQ_HANDLED; |
| 39 | } |
| 40 | |
| 41 | static struct irqaction footbridge_timer_irq = { |
| 42 | .name = "Timer1 timer tick", |
| 43 | .handler = timer1_interrupt, |
Bernhard Walle | b30faba | 2007-05-08 00:35:39 -0700 | [diff] [blame] | 44 | .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | }; |
| 46 | |
| 47 | /* |
| 48 | * Set up timer interrupt. |
| 49 | */ |
| 50 | static void __init footbridge_timer_init(void) |
| 51 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | timer1_latch = (mem_fclk_21285 + 8 * HZ) / (16 * HZ); |
| 53 | |
| 54 | *CSR_TIMER1_CLR = 0; |
| 55 | *CSR_TIMER1_LOAD = timer1_latch; |
| 56 | *CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD | TIMER_CNTL_DIV16; |
| 57 | |
| 58 | setup_irq(IRQ_TIMER1, &footbridge_timer_irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | } |
| 60 | |
| 61 | struct sys_timer footbridge_timer = { |
| 62 | .init = footbridge_timer_init, |
| 63 | .offset = timer1_gettimeoffset, |
| 64 | }; |