aboutsummaryrefslogtreecommitdiff
path: root/arch/avr32/mach-at32ap/sm.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/avr32/mach-at32ap/sm.c')
-rw-r--r--arch/avr32/mach-at32ap/sm.c289
1 files changed, 289 insertions, 0 deletions
diff --git a/arch/avr32/mach-at32ap/sm.c b/arch/avr32/mach-at32ap/sm.c
new file mode 100644
index 00000000000..03306eb0345
--- /dev/null
+++ b/arch/avr32/mach-at32ap/sm.c
@@ -0,0 +1,289 @@
+/*
+ * System Manager driver for AT32AP CPUs
+ *
+ * Copyright (C) 2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/random.h>
+#include <linux/spinlock.h>
+
+#include <asm/intc.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include <asm/arch/sm.h>
+
+#include "sm.h"
+
+#define SM_EIM_IRQ_RESOURCE 1
+#define SM_PM_IRQ_RESOURCE 2
+#define SM_RTC_IRQ_RESOURCE 3
+
+#define to_eim(irqc) container_of(irqc, struct at32_sm, irqc)
+
+struct at32_sm system_manager;
+
+int __init at32_sm_init(void)
+{
+ struct resource *regs;
+ struct at32_sm *sm = &system_manager;
+ int ret = -ENXIO;
+
+ regs = platform_get_resource(&at32_sm_device, IORESOURCE_MEM, 0);
+ if (!regs)
+ goto fail;
+
+ spin_lock_init(&sm->lock);
+ sm->pdev = &at32_sm_device;
+
+ ret = -ENOMEM;
+ sm->regs = ioremap(regs->start, regs->end - regs->start + 1);
+ if (!sm->regs)
+ goto fail;
+
+ return 0;
+
+fail:
+ printk(KERN_ERR "Failed to initialize System Manager: %d\n", ret);
+ return ret;
+}
+
+/*
+ * External Interrupt Module (EIM).
+ *
+ * EIM gets level- or edge-triggered interrupts of either polarity
+ * from the outside and converts it to active-high level-triggered
+ * interrupts that the internal interrupt controller can handle. EIM
+ * also provides masking/unmasking of interrupts, as well as
+ * acknowledging of edge-triggered interrupts.
+ */
+
+static irqreturn_t spurious_eim_interrupt(int irq, void *dev_id,
+ struct pt_regs *regs)
+{
+ printk(KERN_WARNING "Spurious EIM interrupt %d\n", irq);
+ disable_irq(irq);
+ return IRQ_NONE;
+}
+
+static struct irqaction eim_spurious_action = {
+ .handler = spurious_eim_interrupt,
+};
+
+static irqreturn_t eim_handle_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct irq_controller * irqc = dev_id;
+ struct at32_sm *sm = to_eim(irqc);
+ unsigned long pending;
+
+ /*
+ * No need to disable interrupts globally. The interrupt
+ * level relevant to this group must be masked all the time,
+ * so we know that this particular EIM instance will not be
+ * re-entered.
+ */
+ spin_lock(&sm->lock);
+
+ pending = intc_get_pending(sm->irqc.irq_group);
+ if (unlikely(!pending)) {
+ printk(KERN_ERR "EIM (group %u): No interrupts pending!\n",
+ sm->irqc.irq_group);
+ goto unlock;
+ }
+
+ do {
+ struct irqaction *action;
+ unsigned int i;
+
+ i = fls(pending) - 1;
+ pending &= ~(1 << i);
+ action = sm->action[i];
+
+ /* Acknowledge the interrupt */
+ sm_writel(sm, EIM_ICR, 1 << i);
+
+ spin_unlock(&sm->lock);
+
+ if (action->flags & SA_INTERRUPT)
+ local_irq_disable();
+ action->handler(sm->irqc.first_irq + i, action->dev_id, regs);
+ local_irq_enable();
+ spin_lock(&sm->lock);
+ if (action->flags & SA_SAMPLE_RANDOM)
+ add_interrupt_randomness(sm->irqc.first_irq + i);
+ } while (pending);
+
+unlock:
+ spin_unlock(&sm->lock);
+ return IRQ_HANDLED;
+}
+
+static void eim_mask(struct irq_controller *irqc, unsigned int irq)
+{
+ struct at32_sm *sm = to_eim(irqc);
+ unsigned int i;
+
+ i = irq - sm->irqc.first_irq;
+ sm_writel(sm, EIM_IDR, 1 << i);
+}
+
+static void eim_unmask(struct irq_controller *irqc, unsigned int irq)
+{
+ struct at32_sm *sm = to_eim(irqc);
+ unsigned int i;
+
+ i = irq - sm->irqc.first_irq;
+ sm_writel(sm, EIM_IER, 1 << i);
+}
+
+static int eim_setup(struct irq_controller *irqc, unsigned int irq,
+ struct irqaction *action)
+{
+ struct at32_sm *sm = to_eim(irqc);
+ sm->action[irq - sm->irqc.first_irq] = action;
+ /* Acknowledge earlier interrupts */
+ sm_writel(sm, EIM_ICR, (1<<(irq - sm->irqc.first_irq)));
+ eim_unmask(irqc, irq);
+ return 0;
+}
+
+static void eim_free(struct irq_controller *irqc, unsigned int irq,
+ void *dev)
+{
+ struct at32_sm *sm = to_eim(irqc);
+ eim_mask(irqc, irq);
+ sm->action[irq - sm->irqc.first_irq] = &eim_spurious_action;
+}
+
+static int eim_set_type(struct irq_controller *irqc, unsigned int irq,
+ unsigned int type)
+{
+ struct at32_sm *sm = to_eim(irqc);
+ unsigned long flags;
+ u32 value, pattern;
+
+ spin_lock_irqsave(&sm->lock, flags);
+
+ pattern = 1 << (irq - sm->irqc.first_irq);
+
+ value = sm_readl(sm, EIM_MODE);
+ if (type & IRQ_TYPE_LEVEL)
+ value |= pattern;
+ else
+ value &= ~pattern;
+ sm_writel(sm, EIM_MODE, value);
+ value = sm_readl(sm, EIM_EDGE);
+ if (type & IRQ_EDGE_RISING)
+ value |= pattern;
+ else
+ value &= ~pattern;
+ sm_writel(sm, EIM_EDGE, value);
+ value = sm_readl(sm, EIM_LEVEL);
+ if (type & IRQ_LEVEL_HIGH)
+ value |= pattern;
+ else
+ value &= ~pattern;
+ sm_writel(sm, EIM_LEVEL, value);
+
+ spin_unlock_irqrestore(&sm->lock, flags);
+
+ return 0;
+}
+
+static unsigned int eim_get_type(struct irq_controller *irqc,
+ unsigned int irq)
+{
+ struct at32_sm *sm = to_eim(irqc);
+ unsigned long flags;
+ unsigned int type = 0;
+ u32 mode, edge, level, pattern;
+
+ pattern = 1 << (irq - sm->irqc.first_irq);
+
+ spin_lock_irqsave(&sm->lock, flags);
+ mode = sm_readl(sm, EIM_MODE);
+ edge = sm_readl(sm, EIM_EDGE);
+ level = sm_readl(sm, EIM_LEVEL);
+ spin_unlock_irqrestore(&sm->lock, flags);
+
+ if (mode & pattern)
+ type |= IRQ_TYPE_LEVEL;
+ if (edge & pattern)
+ type |= IRQ_EDGE_RISING;
+ if (level & pattern)
+ type |= IRQ_LEVEL_HIGH;
+
+ return type;
+}
+
+static struct irq_controller_class eim_irq_class = {
+ .typename = "EIM",
+ .handle = eim_handle_irq,
+ .setup = eim_setup,
+ .free = eim_free,
+ .mask = eim_mask,
+ .unmask = eim_unmask,
+ .set_type = eim_set_type,
+ .get_type = eim_get_type,
+};
+
+static int __init eim_init(void)
+{
+ struct at32_sm *sm = &system_manager;
+ unsigned int i;
+ u32 pattern;
+ int ret;
+
+ /*
+ * The EIM is really the same module as SM, so register
+ * mapping, etc. has been taken care of already.
+ */
+
+ /*
+ * Find out how many interrupt lines that are actually
+ * implemented in hardware.
+ */
+ sm_writel(sm, EIM_IDR, ~0UL);
+ sm_writel(sm, EIM_MODE, ~0UL);
+ pattern = sm_readl(sm, EIM_MODE);
+ sm->irqc.nr_irqs = fls(pattern);
+
+ ret = -ENOMEM;
+ sm->action = kmalloc(sizeof(*sm->action) * sm->irqc.nr_irqs,
+ GFP_KERNEL);
+ if (!sm->action)
+ goto out;
+
+ for (i = 0; i < sm->irqc.nr_irqs; i++)
+ sm->action[i] = &eim_spurious_action;
+
+ spin_lock_init(&sm->lock);
+ sm->irqc.irq_group = sm->pdev->resource[SM_EIM_IRQ_RESOURCE].start;
+ sm->irqc.class = &eim_irq_class;
+
+ ret = intc_register_controller(&sm->irqc);
+ if (ret < 0)
+ goto out_free_actions;
+
+ printk("EIM: External Interrupt Module at 0x%p, IRQ group %u\n",
+ sm->regs, sm->irqc.irq_group);
+ printk("EIM: Handling %u external IRQs, starting with IRQ%u\n",
+ sm->irqc.nr_irqs, sm->irqc.first_irq);
+
+ return 0;
+
+out_free_actions:
+ kfree(sm->action);
+out:
+ return ret;
+}
+arch_initcall(eim_init);