--- /dev/null
+/*
+ * arch/arm/mach-ks8695/time.c
+ *
+ * Copyright (C) 2006 Ben Dooks <ben@simtec.co.uk>
+ * Copyright (C) 2006 Simtec Electronics
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+#include <linux/clockchips.h>
+
+#include <asm/mach/time.h>
+#include <asm/system_misc.h>
+
+#include <mach/regs-irq.h>
+
+#include "generic.h"
+
+#define KS8695_TMR_OFFSET (0xF0000 + 0xE400)
+#define KS8695_TMR_VA (KS8695_IO_VA + KS8695_TMR_OFFSET)
+#define KS8695_TMR_PA (KS8695_IO_PA + KS8695_TMR_OFFSET)
+
+/*
+ * Timer registers
+ */
+#define KS8695_TMCON (0x00) /* Timer Control Register */
+#define KS8695_T1TC (0x04) /* Timer 1 Timeout Count Register */
+#define KS8695_T0TC (0x08) /* Timer 0 Timeout Count Register */
+#define KS8695_T1PD (0x0C) /* Timer 1 Pulse Count Register */
+#define KS8695_T0PD (0x10) /* Timer 0 Pulse Count Register */
+
+/* Timer Control Register */
+#define TMCON_T1EN (1 << 1) /* Timer 1 Enable */
+#define TMCON_T0EN (1 << 0) /* Timer 0 Enable */
+
+/* Timer0 Timeout Counter Register */
+#define T0TC_WATCHDOG (0xff) /* Enable watchdog mode */
+
+static void ks8695_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ u32 tmcon;
+
+ if (mode == CLOCK_EVT_FEAT_PERIODIC) {
+ u32 rate = DIV_ROUND_CLOSEST(KS8695_CLOCK_RATE, HZ);
+ u32 half = DIV_ROUND_CLOSEST(rate, 2);
+
+ /* Disable timer 1 */
+ tmcon = readl_relaxed(KS8695_TMR_VA + KS8695_TMCON);
+ tmcon &= ~TMCON_T1EN;
+ writel_relaxed(tmcon, KS8695_TMR_VA + KS8695_TMCON);
+
+ /* Both registers need to count down */
+ writel_relaxed(half, KS8695_TMR_VA + KS8695_T1TC);
+ writel_relaxed(half, KS8695_TMR_VA + KS8695_T1PD);
+
+ /* Re-enable timer1 */
+ tmcon |= TMCON_T1EN;
+ writel_relaxed(tmcon, KS8695_TMR_VA + KS8695_TMCON);
+ }
+}
+
+static int ks8695_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+
+{
+ u32 half = DIV_ROUND_CLOSEST(cycles, 2);
+ u32 tmcon;
+
+ /* Disable timer 1 */
+ tmcon = readl_relaxed(KS8695_TMR_VA + KS8695_TMCON);
+ tmcon &= ~TMCON_T1EN;
+ writel_relaxed(tmcon, KS8695_TMR_VA + KS8695_TMCON);
+
+ /* Both registers need to count down */
+ writel_relaxed(half, KS8695_TMR_VA + KS8695_T1TC);
+ writel_relaxed(half, KS8695_TMR_VA + KS8695_T1PD);
+
+ /* Re-enable timer1 */
+ tmcon |= TMCON_T1EN;
+ writel_relaxed(tmcon, KS8695_TMR_VA + KS8695_TMCON);
+
+ return 0;
+}
+
+static struct clock_event_device clockevent_ks8695 = {
+ .name = "ks8695_t1tc",
+ .rating = 300, /* Reasonably fast and accurate clock event */
+ .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
+ .set_next_event = ks8695_set_next_event,
+ .set_mode = ks8695_set_mode,
+};
+
+/*
+ * IRQ handler for the timer.
+ */
+static irqreturn_t ks8695_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = &clockevent_ks8695;
+
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+}
+
+static struct irqaction ks8695_timer_irq = {
+ .name = "ks8695_tick",
+ .flags = IRQF_TIMER,
+ .handler = ks8695_timer_interrupt,
+};
+
+static void ks8695_timer_setup(void)
+{
+ unsigned long tmcon;
+
+ /* Disable timer 0 and 1 */
+ tmcon = readl_relaxed(KS8695_TMR_VA + KS8695_TMCON);
+ tmcon &= ~TMCON_T0EN;
+ tmcon &= ~TMCON_T1EN;
+ writel_relaxed(tmcon, KS8695_TMR_VA + KS8695_TMCON);
+
+ /*
+ * Use timer 1 to fire IRQs on the timeline, minimum 2 cycles
+ * (one on each counter) maximum 2*2^32, but the API will only
+ * accept up to a 32bit full word (0xFFFFFFFFU).
+ */
+ clockevents_config_and_register(&clockevent_ks8695,
+ KS8695_CLOCK_RATE, 2,
+ 0xFFFFFFFFU);
+}
+
+void __init ks8695_timer_init(void)
+{
+ ks8695_timer_setup();
+
+ /* Enable timer interrupts */
+ setup_irq(KS8695_IRQ_TIMER1, &ks8695_timer_irq);
+}
+
+void ks8695_restart(enum reboot_mode reboot_mode, const char *cmd)
+{
+ unsigned int reg;
+
+ if (reboot_mode == REBOOT_SOFT)
+ soft_restart(0);
+
+ /* disable timer0 */
+ reg = readl_relaxed(KS8695_TMR_VA + KS8695_TMCON);
+ writel_relaxed(reg & ~TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
+
+ /* enable watchdog mode */
+ writel_relaxed((10 << 8) | T0TC_WATCHDOG, KS8695_TMR_VA + KS8695_T0TC);
+
+ /* re-enable timer0 */
+ writel_relaxed(reg | TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
+}
Code Review / kvmfornfv.git / blobdiff