diff options
Diffstat (limited to 'arch/unicore32/kernel/irq.c')
| -rw-r--r-- | arch/unicore32/kernel/irq.c | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/arch/unicore32/kernel/irq.c b/arch/unicore32/kernel/irq.c new file mode 100644 index 00000000000..0be5ccd7ccd --- /dev/null +++ b/arch/unicore32/kernel/irq.c @@ -0,0 +1,376 @@ +/* + * linux/arch/unicore32/kernel/irq.c + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * 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/kernel_stat.h> +#include <linux/module.h> +#include <linux/signal.h> +#include <linux/ioport.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/random.h> +#include <linux/smp.h> +#include <linux/init.h> +#include <linux/seq_file.h> +#include <linux/errno.h> +#include <linux/list.h> +#include <linux/kallsyms.h> +#include <linux/proc_fs.h> +#include <linux/syscore_ops.h> +#include <linux/gpio.h> + +#include <mach/hardware.h> + +#include "setup.h" + +/* + * PKUnity GPIO edge detection for IRQs: + * IRQs are generated on Falling-Edge, Rising-Edge, or both. + * Use this instead of directly setting GRER/GFER. + */ +static int GPIO_IRQ_rising_edge; +static int GPIO_IRQ_falling_edge; +static int GPIO_IRQ_mask = 0; + +#define GPIO_MASK(irq) (1 << (irq - IRQ_GPIO0)) + +static int puv3_gpio_type(struct irq_data *d, unsigned int type) +{ + unsigned int mask; + + if (d->irq < IRQ_GPIOHIGH) + mask = 1 << d->irq; + else + mask = GPIO_MASK(d->irq); + + if (type == IRQ_TYPE_PROBE) { + if ((GPIO_IRQ_rising_edge | GPIO_IRQ_falling_edge) & mask) + return 0; + type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING; + } + + if (type & IRQ_TYPE_EDGE_RISING) + GPIO_IRQ_rising_edge |= mask; + else + GPIO_IRQ_rising_edge &= ~mask; + if (type & IRQ_TYPE_EDGE_FALLING) + GPIO_IRQ_falling_edge |= mask; + else + GPIO_IRQ_falling_edge &= ~mask; + + writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER); + writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER); + + return 0; +} + +/* + * GPIO IRQs must be acknowledged. This is for IRQs from 0 to 7. + */ +static void puv3_low_gpio_ack(struct irq_data *d) +{ + writel((1 << d->irq), GPIO_GEDR); +} + +static void puv3_low_gpio_mask(struct irq_data *d) +{ + writel(readl(INTC_ICMR) & ~(1 << d->irq), INTC_ICMR); +} + +static void puv3_low_gpio_unmask(struct irq_data *d) +{ + writel(readl(INTC_ICMR) | (1 << d->irq), INTC_ICMR); +} + +static int puv3_low_gpio_wake(struct irq_data *d, unsigned int on) +{ + if (on) + writel(readl(PM_PWER) | (1 << d->irq), PM_PWER); + else + writel(readl(PM_PWER) & ~(1 << d->irq), PM_PWER); + return 0; +} + +static struct irq_chip puv3_low_gpio_chip = { + .name = "GPIO-low", + .irq_ack = puv3_low_gpio_ack, + .irq_mask = puv3_low_gpio_mask, + .irq_unmask = puv3_low_gpio_unmask, + .irq_set_type = puv3_gpio_type, + .irq_set_wake = puv3_low_gpio_wake, +}; + +/* + * IRQ8 (GPIO0 through 27) handler. We enter here with the + * irq_controller_lock held, and IRQs disabled. Decode the IRQ + * and call the handler. + */ +static void +puv3_gpio_handler(unsigned int irq, struct irq_desc *desc) +{ + unsigned int mask; + + mask = readl(GPIO_GEDR); + do { + /* + * clear down all currently active IRQ sources. + * We will be processing them all. + */ + writel(mask, GPIO_GEDR); + + irq = IRQ_GPIO0; + do { + if (mask & 1) + generic_handle_irq(irq); + mask >>= 1; + irq++; + } while (mask); + mask = readl(GPIO_GEDR); + } while (mask); +} + +/* + * GPIO0-27 edge IRQs need to be handled specially. + * In addition, the IRQs are all collected up into one bit in the + * interrupt controller registers. + */ +static void puv3_high_gpio_ack(struct irq_data *d) +{ + unsigned int mask = GPIO_MASK(d->irq); + + writel(mask, GPIO_GEDR); +} + +static void puv3_high_gpio_mask(struct irq_data *d) +{ + unsigned int mask = GPIO_MASK(d->irq); + + GPIO_IRQ_mask &= ~mask; + + writel(readl(GPIO_GRER) & ~mask, GPIO_GRER); + writel(readl(GPIO_GFER) & ~mask, GPIO_GFER); +} + +static void puv3_high_gpio_unmask(struct irq_data *d) +{ + unsigned int mask = GPIO_MASK(d->irq); + + GPIO_IRQ_mask |= mask; + + writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER); + writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER); +} + +static int puv3_high_gpio_wake(struct irq_data *d, unsigned int on) +{ + if (on) + writel(readl(PM_PWER) | PM_PWER_GPIOHIGH, PM_PWER); + else + writel(readl(PM_PWER) & ~PM_PWER_GPIOHIGH, PM_PWER); + return 0; +} + +static struct irq_chip puv3_high_gpio_chip = { + .name = "GPIO-high", + .irq_ack = puv3_high_gpio_ack, + .irq_mask = puv3_high_gpio_mask, + .irq_unmask = puv3_high_gpio_unmask, + .irq_set_type = puv3_gpio_type, + .irq_set_wake = puv3_high_gpio_wake, +}; + +/* + * We don't need to ACK IRQs on the PKUnity unless they're GPIOs + * this is for internal IRQs i.e. from 8 to 31. + */ +static void puv3_mask_irq(struct irq_data *d) +{ + writel(readl(INTC_ICMR) & ~(1 << d->irq), INTC_ICMR); +} + +static void puv3_unmask_irq(struct irq_data *d) +{ + writel(readl(INTC_ICMR) | (1 << d->irq), INTC_ICMR); +} + +/* + * Apart form GPIOs, only the RTC alarm can be a wakeup event. + */ +static int puv3_set_wake(struct irq_data *d, unsigned int on) +{ + if (d->irq == IRQ_RTCAlarm) { + if (on) + writel(readl(PM_PWER) | PM_PWER_RTC, PM_PWER); + else + writel(readl(PM_PWER) & ~PM_PWER_RTC, PM_PWER); + return 0; + } + return -EINVAL; +} + +static struct irq_chip puv3_normal_chip = { + .name = "PKUnity-v3", + .irq_ack = puv3_mask_irq, + .irq_mask = puv3_mask_irq, + .irq_unmask = puv3_unmask_irq, + .irq_set_wake = puv3_set_wake, +}; + +static struct resource irq_resource = { + .name = "irqs", + .start = io_v2p(PKUNITY_INTC_BASE), + .end = io_v2p(PKUNITY_INTC_BASE) + 0xFFFFF, +}; + +static struct puv3_irq_state { + unsigned int saved; + unsigned int icmr; + unsigned int iclr; + unsigned int iccr; +} puv3_irq_state; + +static int puv3_irq_suspend(void) +{ + struct puv3_irq_state *st = &puv3_irq_state; + + st->saved = 1; + st->icmr = readl(INTC_ICMR); + st->iclr = readl(INTC_ICLR); + st->iccr = readl(INTC_ICCR); + + /* + * Disable all GPIO-based interrupts. + */ + writel(readl(INTC_ICMR) & ~(0x1ff), INTC_ICMR); + + /* + * Set the appropriate edges for wakeup. + */ + writel(readl(PM_PWER) & GPIO_IRQ_rising_edge, GPIO_GRER); + writel(readl(PM_PWER) & GPIO_IRQ_falling_edge, GPIO_GFER); + + /* + * Clear any pending GPIO interrupts. + */ + writel(readl(GPIO_GEDR), GPIO_GEDR); + + return 0; +} + +static void puv3_irq_resume(void) +{ + struct puv3_irq_state *st = &puv3_irq_state; + + if (st->saved) { + writel(st->iccr, INTC_ICCR); + writel(st->iclr, INTC_ICLR); + + writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER); + writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER); + + writel(st->icmr, INTC_ICMR); + } +} + +static struct syscore_ops puv3_irq_syscore_ops = { + .suspend = puv3_irq_suspend, + .resume = puv3_irq_resume, +}; + +static int __init puv3_irq_init_syscore(void) +{ + register_syscore_ops(&puv3_irq_syscore_ops); + return 0; +} + +device_initcall(puv3_irq_init_syscore); + +void __init init_IRQ(void) +{ + unsigned int irq; + + request_resource(&iomem_resource, &irq_resource); + + /* disable all IRQs */ + writel(0, INTC_ICMR); + + /* all IRQs are IRQ, not REAL */ + writel(0, INTC_ICLR); + + /* clear all GPIO edge detects */ + writel(FMASK(8, 0) & ~FIELD(1, 1, GPI_SOFF_REQ), GPIO_GPIR); + writel(0, GPIO_GFER); + writel(0, GPIO_GRER); + writel(0x0FFFFFFF, GPIO_GEDR); + + writel(1, INTC_ICCR); + + for (irq = 0; irq < IRQ_GPIOHIGH; irq++) { + irq_set_chip(irq, &puv3_low_gpio_chip); + irq_set_handler(irq, handle_edge_irq); + irq_modify_status(irq, + IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN, + 0); + } + + for (irq = IRQ_GPIOHIGH + 1; irq < IRQ_GPIO0; irq++) { + irq_set_chip(irq, &puv3_normal_chip); + irq_set_handler(irq, handle_level_irq); + irq_modify_status(irq, + IRQ_NOREQUEST | IRQ_NOAUTOEN, + IRQ_NOPROBE); + } + + for (irq = IRQ_GPIO0; irq <= IRQ_GPIO27; irq++) { + irq_set_chip(irq, &puv3_high_gpio_chip); + irq_set_handler(irq, handle_edge_irq); + irq_modify_status(irq, + IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN, + 0); + } + + /* + * Install handler for GPIO 0-27 edge detect interrupts + */ + irq_set_chip(IRQ_GPIOHIGH, &puv3_normal_chip); + irq_set_chained_handler(IRQ_GPIOHIGH, puv3_gpio_handler); + +#ifdef CONFIG_PUV3_GPIO + puv3_init_gpio(); +#endif +} + +/* + * do_IRQ handles all hardware IRQ's. Decoded IRQs should not + * come via this function. Instead, they should provide their + * own 'handler' + */ +asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + + irq_enter(); + + /* + * Some hardware gives randomly wrong interrupts. Rather + * than crashing, do something sensible. + */ + if (unlikely(irq >= nr_irqs)) { + if (printk_ratelimit()) + printk(KERN_WARNING "Bad IRQ%u\n", irq); + ack_bad_irq(irq); + } else { + generic_handle_irq(irq); + } + + irq_exit(); + set_irq_regs(old_regs); +} + |