| Sascha Hauer | bb6d8c8 | 2006-06-19 15:27:53 +0100 | [diff] [blame] | 1 | /* |
| 2 | * arch/arm/mach-netx/time.c |
| 3 | * |
| 4 | * Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 |
| 8 | * as published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write to the Free Software |
| 17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 18 | */ |
| 19 | |
| 20 | #include <linux/init.h> |
| 21 | #include <linux/interrupt.h> |
| 22 | |
| 23 | #include <asm/hardware.h> |
| 24 | #include <asm/io.h> |
| 25 | #include <asm/mach/time.h> |
| 26 | #include <asm/arch/netx-regs.h> |
| 27 | |
| 28 | /* |
| 29 | * Returns number of us since last clock interrupt. Note that interrupts |
| 30 | * will have been disabled by do_gettimeoffset() |
| 31 | */ |
| 32 | static unsigned long netx_gettimeoffset(void) |
| 33 | { |
| 34 | return readl(NETX_GPIO_COUNTER_CURRENT(0)) / 100; |
| 35 | } |
| 36 | |
| 37 | /* |
| 38 | * IRQ handler for the timer |
| 39 | */ |
| 40 | static irqreturn_t |
| 41 | netx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) |
| 42 | { |
| 43 | write_seqlock(&xtime_lock); |
| 44 | |
| 45 | timer_tick(regs); |
| 46 | write_sequnlock(&xtime_lock); |
| 47 | |
| 48 | /* acknowledge interrupt */ |
| 49 | writel(COUNTER_BIT(0), NETX_GPIO_IRQ); |
| 50 | |
| 51 | return IRQ_HANDLED; |
| 52 | } |
| 53 | |
| 54 | |
| 55 | static struct irqaction netx_timer_irq = { |
| 56 | .name = "NetX Timer Tick", |
| Thomas Gleixner | 52e405e | 2006-07-03 02:20:05 +0200 | [diff] [blame] | 57 | .flags = IRQF_DISABLED | IRQF_TIMER, |
| Sascha Hauer | bb6d8c8 | 2006-06-19 15:27:53 +0100 | [diff] [blame] | 58 | .handler = netx_timer_interrupt, |
| 59 | }; |
| 60 | |
| 61 | /* |
| 62 | * Set up timer interrupt |
| 63 | */ |
| 64 | static void __init netx_timer_init(void) |
| 65 | { |
| 66 | /* disable timer initially */ |
| 67 | writel(0, NETX_GPIO_COUNTER_CTRL(0)); |
| 68 | |
| 69 | /* Reset the timer value to zero */ |
| 70 | writel(0, NETX_GPIO_COUNTER_CURRENT(0)); |
| 71 | |
| 72 | writel(LATCH, NETX_GPIO_COUNTER_MAX(0)); |
| 73 | |
| 74 | /* acknowledge interrupt */ |
| 75 | writel(COUNTER_BIT(0), NETX_GPIO_IRQ); |
| 76 | |
| 77 | /* Enable the interrupt in the specific timer register and start timer */ |
| 78 | writel(COUNTER_BIT(0), NETX_GPIO_IRQ_ENABLE); |
| 79 | writel(NETX_GPIO_COUNTER_CTRL_IRQ_EN | NETX_GPIO_COUNTER_CTRL_RUN, |
| 80 | NETX_GPIO_COUNTER_CTRL(0)); |
| 81 | |
| 82 | setup_irq(NETX_IRQ_TIMER0, &netx_timer_irq); |
| 83 | } |
| 84 | |
| 85 | struct sys_timer netx_timer = { |
| 86 | .init = netx_timer_init, |
| 87 | .offset = netx_gettimeoffset, |
| 88 | }; |