Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / mips / bcm63xx / timer.c

diff --git a/kernel/arch/mips/bcm63xx/timer.c b/kernel/arch/mips/bcm63xx/timer.c
new file mode 100644 (file)
index 0000000..5f11359
--- /dev/null
+++ b/kernel/arch/mips/bcm63xx/timer.c
@@ -0,0 +1,205 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ */
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <bcm63xx_cpu.h>
+#include <bcm63xx_io.h>
+#include <bcm63xx_timer.h>
+#include <bcm63xx_regs.h>
+
+static DEFINE_RAW_SPINLOCK(timer_reg_lock);
+static DEFINE_RAW_SPINLOCK(timer_data_lock);
+static struct clk *periph_clk;
+
+static struct timer_data {
+       void    (*cb)(void *);
+       void    *data;
+} timer_data[BCM63XX_TIMER_COUNT];
+
+static irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+       u32 stat;
+       int i;
+
+       raw_spin_lock(&timer_reg_lock);
+       stat = bcm_timer_readl(TIMER_IRQSTAT_REG);
+       bcm_timer_writel(stat, TIMER_IRQSTAT_REG);
+       raw_spin_unlock(&timer_reg_lock);
+
+       for (i = 0; i < BCM63XX_TIMER_COUNT; i++) {
+               if (!(stat & TIMER_IRQSTAT_TIMER_CAUSE(i)))
+                       continue;
+
+               raw_spin_lock(&timer_data_lock);
+               if (!timer_data[i].cb) {
+                       raw_spin_unlock(&timer_data_lock);
+                       continue;
+               }
+
+               timer_data[i].cb(timer_data[i].data);
+               raw_spin_unlock(&timer_data_lock);
+       }
+
+       return IRQ_HANDLED;
+}
+
+int bcm63xx_timer_enable(int id)
+{
+       u32 reg;
+       unsigned long flags;
+
+       if (id >= BCM63XX_TIMER_COUNT)
+               return -EINVAL;
+
+       raw_spin_lock_irqsave(&timer_reg_lock, flags);
+
+       reg = bcm_timer_readl(TIMER_CTLx_REG(id));
+       reg |= TIMER_CTL_ENABLE_MASK;
+       bcm_timer_writel(reg, TIMER_CTLx_REG(id));
+
+       reg = bcm_timer_readl(TIMER_IRQSTAT_REG);
+       reg |= TIMER_IRQSTAT_TIMER_IR_EN(id);
+       bcm_timer_writel(reg, TIMER_IRQSTAT_REG);
+
+       raw_spin_unlock_irqrestore(&timer_reg_lock, flags);
+       return 0;
+}
+
+EXPORT_SYMBOL(bcm63xx_timer_enable);
+
+int bcm63xx_timer_disable(int id)
+{
+       u32 reg;
+       unsigned long flags;
+
+       if (id >= BCM63XX_TIMER_COUNT)
+               return -EINVAL;
+
+       raw_spin_lock_irqsave(&timer_reg_lock, flags);
+
+       reg = bcm_timer_readl(TIMER_CTLx_REG(id));
+       reg &= ~TIMER_CTL_ENABLE_MASK;
+       bcm_timer_writel(reg, TIMER_CTLx_REG(id));
+
+       reg = bcm_timer_readl(TIMER_IRQSTAT_REG);
+       reg &= ~TIMER_IRQSTAT_TIMER_IR_EN(id);
+       bcm_timer_writel(reg, TIMER_IRQSTAT_REG);
+
+       raw_spin_unlock_irqrestore(&timer_reg_lock, flags);
+       return 0;
+}
+
+EXPORT_SYMBOL(bcm63xx_timer_disable);
+
+int bcm63xx_timer_register(int id, void (*callback)(void *data), void *data)
+{
+       unsigned long flags;
+       int ret;
+
+       if (id >= BCM63XX_TIMER_COUNT || !callback)
+               return -EINVAL;
+
+       ret = 0;
+       raw_spin_lock_irqsave(&timer_data_lock, flags);
+       if (timer_data[id].cb) {
+               ret = -EBUSY;
+               goto out;
+       }
+
+       timer_data[id].cb = callback;
+       timer_data[id].data = data;
+
+out:
+       raw_spin_unlock_irqrestore(&timer_data_lock, flags);
+       return ret;
+}
+
+EXPORT_SYMBOL(bcm63xx_timer_register);
+
+void bcm63xx_timer_unregister(int id)
+{
+       unsigned long flags;
+
+       if (id >= BCM63XX_TIMER_COUNT)
+               return;
+
+       raw_spin_lock_irqsave(&timer_data_lock, flags);
+       timer_data[id].cb = NULL;
+       raw_spin_unlock_irqrestore(&timer_data_lock, flags);
+}
+
+EXPORT_SYMBOL(bcm63xx_timer_unregister);
+
+unsigned int bcm63xx_timer_countdown(unsigned int countdown_us)
+{
+       return (clk_get_rate(periph_clk) / (1000 * 1000)) * countdown_us;
+}
+
+EXPORT_SYMBOL(bcm63xx_timer_countdown);
+
+int bcm63xx_timer_set(int id, int monotonic, unsigned int countdown_us)
+{
+       u32 reg, countdown;
+       unsigned long flags;
+
+       if (id >= BCM63XX_TIMER_COUNT)
+               return -EINVAL;
+
+       countdown = bcm63xx_timer_countdown(countdown_us);
+       if (countdown & ~TIMER_CTL_COUNTDOWN_MASK)
+               return -EINVAL;
+
+       raw_spin_lock_irqsave(&timer_reg_lock, flags);
+       reg = bcm_timer_readl(TIMER_CTLx_REG(id));
+
+       if (monotonic)
+               reg &= ~TIMER_CTL_MONOTONIC_MASK;
+       else
+               reg |= TIMER_CTL_MONOTONIC_MASK;
+
+       reg &= ~TIMER_CTL_COUNTDOWN_MASK;
+       reg |= countdown;
+       bcm_timer_writel(reg, TIMER_CTLx_REG(id));
+
+       raw_spin_unlock_irqrestore(&timer_reg_lock, flags);
+       return 0;
+}
+
+EXPORT_SYMBOL(bcm63xx_timer_set);
+
+int bcm63xx_timer_init(void)
+{
+       int ret, irq;
+       u32 reg;
+
+       reg = bcm_timer_readl(TIMER_IRQSTAT_REG);
+       reg &= ~TIMER_IRQSTAT_TIMER0_IR_EN;
+       reg &= ~TIMER_IRQSTAT_TIMER1_IR_EN;
+       reg &= ~TIMER_IRQSTAT_TIMER2_IR_EN;
+       bcm_timer_writel(reg, TIMER_IRQSTAT_REG);
+
+       periph_clk = clk_get(NULL, "periph");
+       if (IS_ERR(periph_clk))
+               return -ENODEV;
+
+       irq = bcm63xx_get_irq_number(IRQ_TIMER);
+       ret = request_irq(irq, timer_interrupt, 0, "bcm63xx_timer", NULL);
+       if (ret) {
+               printk(KERN_ERR "bcm63xx_timer: failed to register irq\n");
+               return ret;
+       }
+
+       return 0;
+}
+
+arch_initcall(bcm63xx_timer_init);