[PATCH v2 1/8] irqchip: add DesignWare APB ICTL interrupt controller
Sebastian Hesselbarth
sebastian.hesselbarth at gmail.com
Fri Oct 25 17:30:31 EDT 2013
On 10/17/2013 07:37 AM, Sebastian Hesselbarth wrote:
> This adds an irqchip driver and corresponding devicetree binding for the
> secondary interrupt controllers based on Synopsys DesignWare IP dw_apb_ictl.
>
> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
> Reviewed-by: Mark Rutland <mark.rutland at arm.com>
> Reviewed-by: Jisheng Zhang <jszhang at marvell.com>
Thomas (tglx),
can you please look at this and review it? IIRC, Olof already closed
the arm-soc merge window for v3.13, so there is plenty of time to get
this straight. Nevertheless, it would be great to have it in early in
v3.13.
Also, I prefer to have Mark look at the bindings again and maybe
update his remarks with the latest conclusions of KS.
Regards,
Sebastian
> ---
> Changelog:
> v1->v2:
> - reword binding docu for reg property and add FIQ decoding note
> (Suggested by Mark Rutland)
> - add cleanup on error path (Reported by Jisheng Zhang)
> RFCv1->RFCv2:
> - added copyright reference
>
> Cc: Jason Cooper <jason at lakedaemon.net>
> Cc: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
> Cc: Arnd Bergmann <arnd at arndb.de>
> Cc: Thomas Gleixner <tglx at linutronix.de>
> Cc: Mark Rutland <mark.rutland at arm.com>
> Cc: Jisheng Zhang <jszhang at marvell.com>
> Cc: devicetree at vger.kernel.org
> Cc: linux-doc at vger.kernel.org
> Cc: linux-arm-kernel at lists.infradead.org
> Cc: linux-kernel at vger.kernel.org
> ---
> .../interrupt-controller/snps,dw-apb-ictl.txt | 32 +++++
> drivers/irqchip/Kconfig | 4 +
> drivers/irqchip/Makefile | 1 +
> drivers/irqchip/irq-dw-apb-ictl.c | 150 ++++++++++++++++++++
> 4 files changed, 187 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/interrupt-controller/snps,dw-apb-ictl.txt
> create mode 100644 drivers/irqchip/irq-dw-apb-ictl.c
>
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/snps,dw-apb-ictl.txt b/Documentation/devicetree/bindings/interrupt-controller/snps,dw-apb-ictl.txt
> new file mode 100644
> index 0000000..4929117
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interrupt-controller/snps,dw-apb-ictl.txt
> @@ -0,0 +1,32 @@
> +Synopsys DesignWare APB interrupt controller (dw_apb_ictl)
> +
> +Synopsys DesignWare provides interrupt controller IP for APB known as
> +dw_apb_ictl. The IP is used as secondary interrupt controller in some SoCs with
> +APB bus, e.g. Marvell Armada 1500.
> +
> +Required properties:
> +- compatible: shall be "snps,dw-apb-ictl"
> +- reg: physical base address of the controller and length of memory mapped
> + region starting with ENABLE_LOW register
> +- interrupt-controller: identifies the node as an interrupt controller
> +- #interrupt-cells: number of cells to encode an interrupt-specifier, shall be 1
> +- interrupts: interrupt reference to primary interrupt controller
> +- interrupt-parent: (optional) reference specific primary interrupt controller
> +
> +The interrupt sources map to the corresponding bits in the interrupt
> +registers, i.e.
> +- 0 maps to bit 0 of low interrupts,
> +- 1 maps to bit 1 of low interrupts,
> +- 32 maps to bit 0 of high interrupts,
> +- 33 maps to bit 1 of high interrupts,
> +- (optional) fast interrupts start at 64.
> +
> +Example:
> + aic: interrupt-controller at 3000 {
> + compatible = "snps,dw-apb-ictl";
> + reg = <0x3000 0xc00>;
> + interrupt-controller;
> + #interrupt-cells = <1>;
> + interrupt-parent = <&gic>;
> + interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>;
> + };
> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> index 3792a1a..940638d 100644
> --- a/drivers/irqchip/Kconfig
> +++ b/drivers/irqchip/Kconfig
> @@ -30,6 +30,10 @@ config ARM_VIC_NR
> The maximum number of VICs available in the system, for
> power management.
>
> +config DW_APB_ICTL
> + bool
> + select IRQ_DOMAIN
> +
> config IMGPDC_IRQ
> bool
> select GENERIC_IRQ_CHIP
> diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
> index c60b901..6427323 100644
> --- a/drivers/irqchip/Makefile
> +++ b/drivers/irqchip/Makefile
> @@ -6,6 +6,7 @@ obj-$(CONFIG_ARCH_MMP) += irq-mmp.o
> obj-$(CONFIG_ARCH_MVEBU) += irq-armada-370-xp.o
> obj-$(CONFIG_ARCH_MXS) += irq-mxs.o
> obj-$(CONFIG_ARCH_S3C24XX) += irq-s3c24xx.o
> +obj-$(CONFIG_DW_APB_ICTL) += irq-dw-apb-ictl.o
> obj-$(CONFIG_METAG) += irq-metag-ext.o
> obj-$(CONFIG_METAG_PERFCOUNTER_IRQS) += irq-metag.o
> obj-$(CONFIG_ARCH_MOXART) += irq-moxart.o
> diff --git a/drivers/irqchip/irq-dw-apb-ictl.c b/drivers/irqchip/irq-dw-apb-ictl.c
> new file mode 100644
> index 0000000..31e231e
> --- /dev/null
> +++ b/drivers/irqchip/irq-dw-apb-ictl.c
> @@ -0,0 +1,150 @@
> +/*
> + * Synopsys DW APB ICTL irqchip driver.
> + *
> + * Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
> + *
> + * based on GPL'ed 2.6 kernel sources
> + * (c) Marvell International Ltd.
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2. This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + */
> +
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/irqchip/chained_irq.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +
> +#include "irqchip.h"
> +
> +#define APB_INT_ENABLE_L 0x00
> +#define APB_INT_ENABLE_H 0x04
> +#define APB_INT_MASK_L 0x08
> +#define APB_INT_MASK_H 0x0c
> +#define APB_INT_FINALSTATUS_L 0x30
> +#define APB_INT_FINALSTATUS_H 0x34
> +
> +static void dw_apb_ictl_handler(unsigned int irq, struct irq_desc *desc)
> +{
> + struct irq_chip *chip = irq_get_chip(irq);
> + struct irq_chip_generic *gc = irq_get_handler_data(irq);
> + struct irq_domain *d = gc->private;
> + u32 stat;
> + int n;
> +
> + chained_irq_enter(chip, desc);
> +
> + for (n = 0; n < gc->num_ct; n++) {
> + stat = readl_relaxed(gc->reg_base +
> + APB_INT_FINALSTATUS_L + 4 * n);
> + while (stat) {
> + u32 hwirq = ffs(stat) - 1;
> + generic_handle_irq(irq_find_mapping(d,
> + gc->irq_base + hwirq + 32 * n));
> + stat &= ~(1 << hwirq);
> + }
> + }
> +
> + chained_irq_exit(chip, desc);
> +}
> +
> +static int __init dw_apb_ictl_init(struct device_node *np,
> + struct device_node *parent)
> +{
> + unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
> + struct resource r;
> + struct irq_domain *domain;
> + struct irq_chip_generic *gc;
> + void __iomem *iobase;
> + int ret, nrirqs, irq;
> + u32 reg;
> +
> + /* Map the parent interrupt for the chained handler */
> + irq = irq_of_parse_and_map(np, 0);
> + if (irq <= 0) {
> + pr_err("%s: unable to parse irq\n", np->full_name);
> + return -EINVAL;
> + }
> +
> + ret = of_address_to_resource(np, 0, &r);
> + if (ret) {
> + pr_err("%s: unable to get resource\n", np->full_name);
> + return ret;
> + }
> +
> + if (!request_mem_region(r.start, resource_size(&r), np->full_name)) {
> + pr_err("%s: unable to request mem region\n", np->full_name);
> + return -ENOMEM;
> + }
> +
> + iobase = ioremap(r.start, resource_size(&r));
> + if (!iobase) {
> + pr_err("%s: unable to map resource\n", np->full_name);
> + ret = -ENOMEM;
> + goto err_release;
> + }
> +
> + /*
> + * DW IP can be configured to allow 2-64 irqs. We can determine
> + * the number of irqs supported by writing into enable register
> + * and look for bits not set, as corresponding flip-flops will
> + * have been removed by sythesis tool.
> + */
> +
> + /* mask and enable all interrupts */
> + writel(~0, iobase + APB_INT_MASK_L);
> + writel(~0, iobase + APB_INT_MASK_H);
> + writel(~0, iobase + APB_INT_ENABLE_L);
> + writel(~0, iobase + APB_INT_ENABLE_H);
> +
> + reg = readl(iobase + APB_INT_ENABLE_H);
> + if (reg)
> + nrirqs = 32 + fls(reg);
> + else
> + nrirqs = fls(readl(iobase + APB_INT_ENABLE_L));
> +
> + domain = irq_domain_add_linear(np, nrirqs,
> + &irq_generic_chip_ops, NULL);
> + if (!domain) {
> + pr_err("%s: unable to add irq domain\n", np->full_name);
> + ret = -ENOMEM;
> + goto err_unmap;
> + }
> +
> + ret = irq_alloc_domain_generic_chips(domain, 32, (nrirqs > 32) ? 2 : 1,
> + np->name, handle_level_irq, clr, 0,
> + IRQ_GC_INIT_MASK_CACHE);
> + if (ret) {
> + pr_err("%s: unable to alloc irq domain gc\n", np->full_name);
> + goto err_unmap;
> + }
> +
> + gc = irq_get_domain_generic_chip(domain, 0);
> + gc->private = domain;
> + gc->reg_base = iobase;
> +
> + gc->chip_types[0].regs.mask = APB_INT_MASK_L;
> + gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit;
> + gc->chip_types[0].chip.irq_unmask = irq_gc_mask_clr_bit;
> +
> + if (nrirqs > 32) {
> + gc->chip_types[1].regs.mask = APB_INT_MASK_H;
> + gc->chip_types[1].chip.irq_mask = irq_gc_mask_set_bit;
> + gc->chip_types[1].chip.irq_unmask = irq_gc_mask_clr_bit;
> + }
> +
> + irq_set_handler_data(irq, gc);
> + irq_set_chained_handler(irq, dw_apb_ictl_handler);
> +
> + return 0;
> +
> +err_unmap:
> + iounmap(iobase);
> +err_release:
> + release_mem_region(r.start, resource_size(&r));
> + return ret;
> +}
> +IRQCHIP_DECLARE(dw_apb_ictl,
> + "snps,dw-apb-ictl", dw_apb_ictl_init);
>
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