[PATCH 3/3] ARM: S5PV310: Add external interrupt support
Jongsun Han
jongsun.han at samsung.com
Fri Oct 8 06:06:26 EDT 2010
On Thursday, October 07, 2010 1:25 PM Jongsun Han wrote:
>
> > This patch adds the external interrupt support.
> > All external interrupts are transferred to GIC through interrupt combiner.
> >
> > Signed-off-by: Jongsun Han <jongsun.han at samsung.com>
> > Signed-off-by: Jongpill Lee <boyko.lee at samsung.com>
> > ---
> > arch/arm/mach-s5pv310/Makefile | 2 +-
> > arch/arm/mach-s5pv310/irq-eint.c | 257
> ++++++++++++++++++++++++++++++++++++++
> > 2 files changed, 258 insertions(+), 1 deletions(-)
> > create mode 100644 arch/arm/mach-s5pv310/irq-eint.c
> >
> > diff --git a/arch/arm/mach-s5pv310/Makefile b/arch/arm/mach-s5pv310/Makefile
> > index d17c8c7..7b91a9b 100644
> > --- a/arch/arm/mach-s5pv310/Makefile
> > +++ b/arch/arm/mach-s5pv310/Makefile
> > @@ -13,7 +13,7 @@ obj- :=
> > # Core support for S5PV310 system
> >
> > obj-$(CONFIG_CPU_S5PV310) += cpu.o init.o clock.o irq-combiner.o
> > -obj-$(CONFIG_CPU_S5PV310) += setup-i2c0.o time.o
> > +obj-$(CONFIG_CPU_S5PV310) += setup-i2c0.o time.o irq-eint.o
> > obj-$(CONFIG_CPU_FREQ) += cpufreq.o
> >
> > obj-$(CONFIG_SMP) += platsmp.o headsmp.o
> > diff --git a/arch/arm/mach-s5pv310/irq-eint.c b/arch/arm/mach-s5pv310/irq-
> eint.c
> > new file mode 100644
> > index 0000000..5eb464b
> > --- /dev/null
> > +++ b/arch/arm/mach-s5pv310/irq-eint.c
> > @@ -0,0 +1,257 @@
> > +/* linux/arch/arm/mach-s5pv310/irq-eint.c
> > + *
> > + * Copyright (c) 2010 Samsung Electronics Co., Ltd.
> > + * http://www.samsung.com
> > + *
> > + * S5PV310 - IRQ EINT support
> > + *
> > + * 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.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/irq.h>
> > +#include <linux/io.h>
> > +#include <linux/sysdev.h>
> > +#include <linux/gpio.h>
> > +
> > +#include <plat/regs-irqtype.h>
> > +#include <plat/pm.h>
> > +#include <plat/cpu.h>
> > +#include <plat/gpio-cfg.h>
> > +
> > +#include <mach/map.h>
> > +#include <mach/regs-gpio.h>
> > +
> > +static DEFINE_SPINLOCK(eint_lock);
> > +
> > +static unsigned int s5pv310_get_irq_nr(unsigned int number)
> > +{
> > + u32 ret = 0;
> > +
> > + switch (number) {
> > + case 0 ... 3:
> > + ret = (number + IRQ_EINT0);
> > + break;
> > + case 4 ... 7:
> > + ret = (number + (IRQ_EINT4 - 4));
> > + break;
> > + case 8 ... 15:
> > + ret = (number + (IRQ_EINT8 - 8));
> > + break;
> > + default:
> > + printk(KERN_ERR "number available : %d\n", number);
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static unsigned int s5pv310_irq_split(unsigned int number)
> > +{
> > + u32 ret;
> > + u32 test = number;
> > +
> > + ret = do_div(test, IRQ_EINT_BASE);
> > +
> > + do_div(ret, 8);
> > +
> > + return ret;
> > +}
> > +
> > +static unsigned int s5pv310_irq_to_bit(unsigned int irq)
> > +{
> > + u32 ret;
> > + u32 tmp;
> > +
> > + tmp = do_div(irq, IRQ_EINT_BASE);
> > +
> > + ret = do_div(tmp, 8);
> > +
> > + return 1 << ret;
> > +}
> > +
> > +static inline void s5pv310_irq_eint_mask(unsigned int irq)
> > +{
> > + u32 mask;
> > +
> > + spin_lock(&eint_lock);
> > + mask = __raw_readl(S5P_EINT_MASK(s5pv310_irq_split(irq)));
> > + mask |= s5pv310_irq_to_bit(irq);
> > + __raw_writel(mask, S5P_EINT_MASK(s5pv310_irq_split(irq)));
> > + spin_unlock(&eint_lock);
> > +}
> > +
> > +static void s5pv310_irq_eint_unmask(unsigned int irq)
> > +{
> > + u32 mask;
> > +
> > + spin_lock(&eint_lock);
> > + mask = __raw_readl(S5P_EINT_MASK(s5pv310_irq_split(irq)));
> > + mask &= ~(s5pv310_irq_to_bit(irq));
> > + __raw_writel(mask, S5P_EINT_MASK(s5pv310_irq_split(irq)));
> > + spin_unlock(&eint_lock);
> > +}
> > +
> > +static inline void s5pv310_irq_eint_ack(unsigned int irq)
> > +{
> > + spin_lock(&eint_lock);
> > + __raw_writel(s5pv310_irq_to_bit(irq),
> > + S5P_EINT_PEND(s5pv310_irq_split(irq)));
> > + spin_unlock(&eint_lock);
> > +}
> > +
> > +static void s5pv310_irq_eint_maskack(unsigned int irq)
> > +{
> > + s5pv310_irq_eint_mask(irq);
> > + s5pv310_irq_eint_ack(irq);
> > +}
> > +
> > +static int s5pv310_irq_eint_set_type(unsigned int irq, unsigned int type)
> > +{
> > + int offs = EINT_OFFSET(irq);
> > + int shift;
> > + u32 ctrl, mask;
> > + u32 newvalue = 0;
> > +
> > + switch (type) {
> > + case IRQ_TYPE_EDGE_RISING:
> > + newvalue = S5P_IRQ_TYPE_EDGE_RISING;
> > + break;
> > +
> > + case IRQ_TYPE_EDGE_FALLING:
> > + newvalue = S5P_IRQ_TYPE_EDGE_FALLING;
> > + break;
> > +
> > + case IRQ_TYPE_EDGE_BOTH:
> > + newvalue = S5P_IRQ_TYPE_EDGE_BOTH;
> > + break;
> > +
> > + case IRQ_TYPE_LEVEL_LOW:
>
> > + if (irq == IRQ_EINT(5))
> > + newvalue = S5P_IRQ_TYPE_LEVEL_HIGH;
> > + else
> > + newvalue = S5P_IRQ_TYPE_LEVEL_LOW;
>
> This one looks like an ugle hack. What is it for?
>
Hi,Marek
It's dummy code.
I'll make patch
> > + break;
> > +
> > + case IRQ_TYPE_LEVEL_HIGH:
> > + newvalue = S5P_IRQ_TYPE_LEVEL_HIGH;
> > + break;
> > +
> > + default:
> > + printk(KERN_ERR "No such irq type %d", type);
> > + return -EINVAL;
> > + }
> > +
> > + shift = (offs & 0x7) * 4;
> > + mask = 0x7 << shift;
> > +
> > + spin_lock(&eint_lock);
> > + ctrl = __raw_readl(S5P_EINT_CON(s5pv310_irq_split(irq)));
> > + ctrl &= ~mask;
> > + ctrl |= newvalue << shift;
> > + __raw_writel(ctrl, S5P_EINT_CON(s5pv310_irq_split(irq)));
> > + spin_unlock(&eint_lock);
> > +
> > + if ((0 <= offs) && (offs < 8))
> > + s3c_gpio_cfgpin(EINT_GPIO_0(offs & 0x7), EINT_MODE);
> > +
> > + else if ((8 <= offs) && (offs < 16))
> > + s3c_gpio_cfgpin(EINT_GPIO_1(offs & 0x7), EINT_MODE);
> > +
> > + else if ((16 <= offs) && (offs < 24))
> > + s3c_gpio_cfgpin(EINT_GPIO_2(offs & 0x7), EINT_MODE);
> > +
> > + else if ((24 <= offs) && (offs < 32))
> > + s3c_gpio_cfgpin(EINT_GPIO_3(offs & 0x7), EINT_MODE);
> > +
> > + else
> > + printk(KERN_ERR "No such irq number %d", offs);
> > +
> > + return 0;
> > +}
> > +
> > +static struct irq_chip s5pv310_irq_eint = {
> > + .name = "s5pv310-eint",
> > + .mask = s5pv310_irq_eint_mask,
> > + .unmask = s5pv310_irq_eint_unmask,
> > + .mask_ack = s5pv310_irq_eint_maskack,
> > + .ack = s5pv310_irq_eint_ack,
> > + .set_type = s5pv310_irq_eint_set_type,
> > +#ifdef CONFIG_PM
> > + .set_wake = s3c_irqext_wake,
> > +#endif
> > +};
> > +
> > +/* s5pv310_irq_demux_eint
> > + *
> > + * This function demuxes the IRQ from from EINTs 16 to 31.
> > + * It is designed to be inlined into the specific handler
> > + * s5p_irq_demux_eintX_Y.
> > + *
> > + * Each EINT pend/mask registers handle eight of them.
> > + */
> > +static inline void s5pv310_irq_demux_eint(unsigned int start)
> > +{
> > + unsigned int irq;
> > +
> > + u32 status = __raw_readl(S5P_EINT_PEND(s5pv310_irq_split(start)));
> > + u32 mask = __raw_readl(S5P_EINT_MASK(s5pv310_irq_split(start)));
> > +
> > + status &= ~mask;
> > + status &= 0xff;
> > +
> > + while (status) {
> > + irq = fls(status) - 1;
> > + generic_handle_irq(irq + start);
> > + status &= ~(1 << irq);
> > + }
> > +}
> > +
> > +static void s5pv310_irq_demux_eint16_31(unsigned int irq, struct irq_desc
> *desc)
> > +{
> > + s5pv310_irq_demux_eint(IRQ_EINT(16));
> > + s5pv310_irq_demux_eint(IRQ_EINT(24));
> > +}
> > +
> > +static void s5pv310_irq_eint0_15(unsigned int irq, struct irq_desc *desc)
> > +{
> > + u32 i;
> > + struct irq_chip *chip = get_irq_chip(irq);
> > +
> > + chip->mask(irq);
> > +
> > + if (chip->ack)
> > + chip->ack(irq);
> > +
> > + for (i = 0 ; i <= 15 ; i++) {
> > + if (irq == s5pv310_get_irq_nr(i)) {
> > + generic_handle_irq(IRQ_EINT(i));
> > + break;
> > + }
> > + }
> > +
> > + chip->unmask(irq);
> > +}
>
> Am I right that this chained handler is just a simple proxy? If so is it
> really
> needed?
>
No,
this chained handler calls gic ack function and then eint ack fuction is
called handle_level_irq.
> > +
> > +int __init s5pv310_init_irq_eint(void)
> > +{
> > + int irq;
> > +
> > + for (irq = 0 ; irq <= 31 ; irq++) {
> > + set_irq_chip(IRQ_EINT(irq), &s5pv310_irq_eint);
> > + set_irq_handler(IRQ_EINT(irq), handle_level_irq);
> > + set_irq_flags(IRQ_EINT(irq), IRQF_VALID);
> > + }
> > +
> > + set_irq_chained_handler(IRQ_EINT16_31, s5pv310_irq_demux_eint16_31);
> > +
> > + for (irq = 0 ; irq <= 15 ; irq++)
> > + set_irq_chained_handler(s5pv310_get_irq_nr(irq),
> > + s5pv310_irq_eint0_15);
> > +
> > + return 0;
> > +}
> > +
> > +arch_initcall(s5pv310_init_irq_eint);
>
> Best regards
> --
> Marek Szyprowski
> Samsung Poland R&D Center
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
More information about the linux-arm-kernel
mailing list