[PATCH v3 01/19] ARM: GIC: move some bits of GICv2 to a library-type file
Marc Zyngier
marc.zyngier at arm.com
Mon May 12 09:29:57 PDT 2014
On Fri, May 09 2014 at 3:05:12 pm BST, Christoffer Dall <christoffer.dall at linaro.org> wrote:
> On Wed, Apr 16, 2014 at 02:39:33PM +0100, Marc Zyngier wrote:
>> A few GICv2 low-level function are actually very useful to GICv3,
>> and it makes some sense to share them across the two drivers.
>> They end-up in their own file, with an additional parameter used
>> to ensure an optional synchronization (unused on GICv2).
>>
>> Cc: Thomas Gleixner <tglx at linutronix.de>
>> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
>> ---
>> drivers/irqchip/Makefile | 2 +-
>> drivers/irqchip/irq-gic-common.c | 107 +++++++++++++++++++++++++++++++++++++++
>> drivers/irqchip/irq-gic-common.h | 29 +++++++++++
>> drivers/irqchip/irq-gic.c | 59 ++-------------------
>> 4 files changed, 141 insertions(+), 56 deletions(-)
>> create mode 100644 drivers/irqchip/irq-gic-common.c
>> create mode 100644 drivers/irqchip/irq-gic-common.h
>>
>> diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
>> index 5194afb..22e616c 100644
>> --- a/drivers/irqchip/Makefile
>> +++ b/drivers/irqchip/Makefile
>> @@ -13,7 +13,7 @@ obj-$(CONFIG_ARCH_MOXART) += irq-moxart.o
>> obj-$(CONFIG_ORION_IRQCHIP) += irq-orion.o
>> obj-$(CONFIG_ARCH_SUNXI) += irq-sun4i.o
>> obj-$(CONFIG_ARCH_SPEAR3XX) += spear-shirq.o
>> -obj-$(CONFIG_ARM_GIC) += irq-gic.o
>> +obj-$(CONFIG_ARM_GIC) += irq-gic.o irq-gic-common.o
>> obj-$(CONFIG_ARM_NVIC) += irq-nvic.o
>> obj-$(CONFIG_ARM_VIC) += irq-vic.o
>> obj-$(CONFIG_IMGPDC_IRQ) += irq-imgpdc.o
>> diff --git a/drivers/irqchip/irq-gic-common.c b/drivers/irqchip/irq-gic-common.c
>> new file mode 100644
>> index 0000000..48e596e
>> --- /dev/null
>> +++ b/drivers/irqchip/irq-gic-common.c
>> @@ -0,0 +1,107 @@
>> +/*
>> + * Copyright (C) 2002 ARM Limited, All Rights Reserved.
>> + *
>> + * 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.
>> + *
>> + * 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, see <http://www.gnu.org/licenses/>.
>> + */
>> +
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/irq.h>
>> +#include <linux/irqchip/arm-gic.h>
>> +
>> +#include "irq-gic-common.h"
>> +
>> +void gic_configure_irq(unsigned int irq, unsigned int type,
>> + void __iomem *base, void (*sync_access)(void))
>
> use tabs instead of spaces
Sure.
>> +{
>> + u32 enablemask = 1 << (irq % 32);
>> + u32 enableoff = (irq / 32) * 4;
>> + u32 confmask = 0x2 << ((irq % 16) * 2);
>> + u32 confoff = (irq / 16) * 4;
>> + bool enabled = false;
>> + u32 val;
>> +
>> + val = readl_relaxed(base + GIC_DIST_CONFIG + confoff);
>> + if (type == IRQ_TYPE_LEVEL_HIGH)
>> + val &= ~confmask;
>> + else if (type == IRQ_TYPE_EDGE_RISING)
>> + val |= confmask;
>> +
>> + /*
>> + * As recommended by the spec, disable the interrupt before changing
>> + * the configuration
>> + */
>> + if (readl_relaxed(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) {
>> + writel_relaxed(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff);
>> + if (sync_access)
>> + sync_access();
>> + enabled = true;
>> + }
>> +
>> + writel_relaxed(val, base + GIC_DIST_CONFIG + confoff);
>
> Super nit: The other functions are very nicely commented but this one
> actually doesn't explain which aspect of configuration the
> "gic_configure_irq" performs; the fact that the config register deals
> with level/edge trigger high/low may not be obvious to everyone.
>
> Not worth a re-spin just for this though.
Bah. I'll add a comment.
>> +
>> + if (enabled) {
>> + writel_relaxed(enablemask, base + GIC_DIST_ENABLE_SET + enableoff);
>> + if (sync_access)
>> + sync_access();
>> + }
>> +}
>> +
>> +void __init gic_dist_config(void __iomem *base, int gic_irqs,
>> + void (*sync_access)(void))
>> +{
>> + unsigned int i;
>> +
>> + /*
>> + * Set all global interrupts to be level triggered, active low.
>> + */
>> + for (i = 32; i < gic_irqs; i += 16)
>> + writel_relaxed(0, base + GIC_DIST_CONFIG + i / 4);
>> +
>> + /*
>> + * Set priority on all global interrupts.
>> + */
>> + for (i = 32; i < gic_irqs; i += 4)
>> + writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i);
>> +
>> + /*
>> + * Disable all interrupts. Leave the PPI and SGIs alone
>> + * as they are enabled by redistributor registers.
>> + */
>> + for (i = 32; i < gic_irqs; i += 32)
>> + writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i / 8);
>> +
>> + if (sync_access)
>> + sync_access();
>> +}
>> +
>> +void gic_cpu_config(void __iomem *base, void (*sync_access)(void))
>> +{
>> + int i;
>> +
>> + /*
>> + * Deal with the banked PPI and SGI interrupts - disable all
>> + * PPI interrupts, ensure all SGI interrupts are enabled.
>> + */
>> + writel_relaxed(0xffff0000, base + GIC_DIST_ENABLE_CLEAR);
>> + writel_relaxed(0x0000ffff, base + GIC_DIST_ENABLE_SET);
>> +
>> + /*
>> + * Set priority on PPI and SGI interrupts
>> + */
>> + for (i = 0; i < 32; i += 4)
>> + writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i * 4 / 4);
>> +
>> + if (sync_access)
>> + sync_access();
>> +}
>> diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
>> new file mode 100644
>> index 0000000..b41f024
>> --- /dev/null
>> +++ b/drivers/irqchip/irq-gic-common.h
>> @@ -0,0 +1,29 @@
>> +/*
>> + * Copyright (C) 2002 ARM Limited, All Rights Reserved.
>> + *
>> + * 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.
>> + *
>> + * 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, see <http://www.gnu.org/licenses/>.
>> + */
>> +
>> +#ifndef _IRQ_GIC_COMMON_H
>> +#define _IRQ_GIC_COMMON_H
>> +
>> +#include <linux/of.h>
>> +#include <linux/irqdomain.h>
>> +
>> +void gic_configure_irq(unsigned int irq, unsigned int type,
>> + void __iomem *base, void (*sync_access)(void));
>> +void gic_dist_config(void __iomem *base, int gic_irqs,
>> + void (*sync_access)(void));
>> +void gic_cpu_config(void __iomem *base, void (*sync_access)(void));
>> +
>> +#endif /* _IRQ_GIC_COMMON_H */
>> diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
>> index 341c601..09ab3a3 100644
>> --- a/drivers/irqchip/irq-gic.c
>> +++ b/drivers/irqchip/irq-gic.c
>> @@ -46,6 +46,7 @@
>> #include <asm/exception.h>
>> #include <asm/smp_plat.h>
>>
>> +#include "irq-gic-common.h"
>> #include "irqchip.h"
>>
>> union gic_base {
>> @@ -188,12 +189,6 @@ static int gic_set_type(struct irq_data *d, unsigned int type)
>> {
>> void __iomem *base = gic_dist_base(d);
>> unsigned int gicirq = gic_irq(d);
>> - u32 enablemask = 1 << (gicirq % 32);
>> - u32 enableoff = (gicirq / 32) * 4;
>> - u32 confmask = 0x2 << ((gicirq % 16) * 2);
>> - u32 confoff = (gicirq / 16) * 4;
>> - bool enabled = false;
>> - u32 val;
>>
>> /* Interrupt configuration for SGIs can't be changed */
>> if (gicirq < 16)
>> @@ -207,25 +202,7 @@ static int gic_set_type(struct irq_data *d, unsigned int type)
>> if (gic_arch_extn.irq_set_type)
>> gic_arch_extn.irq_set_type(d, type);
>>
>> - val = readl_relaxed(base + GIC_DIST_CONFIG + confoff);
>> - if (type == IRQ_TYPE_LEVEL_HIGH)
>> - val &= ~confmask;
>> - else if (type == IRQ_TYPE_EDGE_RISING)
>> - val |= confmask;
>> -
>> - /*
>> - * As recommended by the spec, disable the interrupt before changing
>> - * the configuration
>> - */
>> - if (readl_relaxed(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) {
>> - writel_relaxed(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff);
>> - enabled = true;
>> - }
>> -
>> - writel_relaxed(val, base + GIC_DIST_CONFIG + confoff);
>> -
>> - if (enabled)
>> - writel_relaxed(enablemask, base + GIC_DIST_ENABLE_SET + enableoff);
>> + gic_configure_irq(gicirq, type, base, NULL);
>>
>> raw_spin_unlock(&irq_controller_lock);
>>
>> @@ -383,12 +360,6 @@ static void __init gic_dist_init(struct gic_chip_data *gic)
>> writel_relaxed(0, base + GIC_DIST_CTRL);
>>
>> /*
>> - * Set all global interrupts to be level triggered, active low.
>> - */
>> - for (i = 32; i < gic_irqs; i += 16)
>> - writel_relaxed(0, base + GIC_DIST_CONFIG + i * 4 / 16);
>> -
>> - /*
>> * Set all global interrupts to this CPU only.
>> */
>> cpumask = gic_get_cpumask(gic);
>> @@ -397,18 +368,7 @@ static void __init gic_dist_init(struct gic_chip_data *gic)
>> for (i = 32; i < gic_irqs; i += 4)
>> writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
>>
>> - /*
>> - * Set priority on all global interrupts.
>> - */
>> - for (i = 32; i < gic_irqs; i += 4)
>> - writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i * 4 / 4);
>> -
>> - /*
>> - * Disable all interrupts. Leave the PPI and SGIs alone
>> - * as these enables are banked registers.
>> - */
>> - for (i = 32; i < gic_irqs; i += 32)
>> - writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i * 4 / 32);
>> + gic_dist_config(base, gic_irqs, NULL);
>>
>> writel_relaxed(1, base + GIC_DIST_CTRL);
>> }
>> @@ -435,18 +395,7 @@ static void gic_cpu_init(struct gic_chip_data *gic)
>> if (i != cpu)
>> gic_cpu_map[i] &= ~cpu_mask;
>>
>> - /*
>> - * Deal with the banked PPI and SGI interrupts - disable all
>> - * PPI interrupts, ensure all SGI interrupts are enabled.
>> - */
>> - writel_relaxed(0xffff0000, dist_base + GIC_DIST_ENABLE_CLEAR);
>> - writel_relaxed(0x0000ffff, dist_base + GIC_DIST_ENABLE_SET);
>> -
>> - /*
>> - * Set priority on PPI and SGI interrupts
>> - */
>> - for (i = 0; i < 32; i += 4)
>> - writel_relaxed(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4 / 4);
>> + gic_cpu_config(dist_base, NULL);
>>
>> writel_relaxed(0xf0, base + GIC_CPU_PRIMASK);
>> writel_relaxed(1, base + GIC_CPU_CTRL);
>> --
>> 1.8.3.4
>>
>
> Acked-by: Christoffer Dall <christoffer.dall at linaro.org>
Thanks,
M.
--
Jazz is not dead. It just smells funny.
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