From 4235ff50cf98dd42ba15175687570f9f03e124a1 Mon Sep 17 00:00:00 2001 From: Miodrag Dinic Date: Fri, 29 Dec 2017 16:41:46 +0100 Subject: irqchip/irq-goldfish-pic: Add Goldfish PIC driver Add device driver for a virtual programmable interrupt controller The virtual PIC is designed as a device tree-based interrupt controller. The compatible string used by OS for binding the driver is "google,goldfish-pic". Signed-off-by: Miodrag Dinic Signed-off-by: Goran Ferenc Signed-off-by: Aleksandar Markovic Signed-off-by: Marc Zyngier --- drivers/irqchip/Kconfig | 8 +++ drivers/irqchip/Makefile | 1 + drivers/irqchip/irq-goldfish-pic.c | 139 +++++++++++++++++++++++++++++++++++++ 3 files changed, 148 insertions(+) create mode 100644 drivers/irqchip/irq-goldfish-pic.c (limited to 'drivers/irqchip') diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index c70476b34a53..d913aec85109 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -343,4 +343,12 @@ config MESON_IRQ_GPIO help Support Meson SoC Family GPIO Interrupt Multiplexer +config GOLDFISH_PIC + bool "Goldfish programmable interrupt controller" + depends on MIPS && (GOLDFISH || COMPILE_TEST) + select IRQ_DOMAIN + help + Say yes here to enable Goldfish interrupt controller driver used + for Goldfish based virtual platforms. + endmenu diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index d2df34a54d38..d27e3e3619e0 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -84,3 +84,4 @@ obj-$(CONFIG_QCOM_IRQ_COMBINER) += qcom-irq-combiner.o obj-$(CONFIG_IRQ_UNIPHIER_AIDET) += irq-uniphier-aidet.o obj-$(CONFIG_ARCH_SYNQUACER) += irq-sni-exiu.o obj-$(CONFIG_MESON_IRQ_GPIO) += irq-meson-gpio.o +obj-$(CONFIG_GOLDFISH_PIC) += irq-goldfish-pic.o diff --git a/drivers/irqchip/irq-goldfish-pic.c b/drivers/irqchip/irq-goldfish-pic.c new file mode 100644 index 000000000000..2a92f03c73e4 --- /dev/null +++ b/drivers/irqchip/irq-goldfish-pic.c @@ -0,0 +1,139 @@ +/* + * Driver for MIPS Goldfish Programmable Interrupt Controller. + * + * Author: Miodrag Dinic + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include + +#define GFPIC_NR_IRQS 32 + +/* 8..39 Cascaded Goldfish PIC interrupts */ +#define GFPIC_IRQ_BASE 8 + +#define GFPIC_REG_IRQ_PENDING 0x04 +#define GFPIC_REG_IRQ_DISABLE_ALL 0x08 +#define GFPIC_REG_IRQ_DISABLE 0x0c +#define GFPIC_REG_IRQ_ENABLE 0x10 + +struct goldfish_pic_data { + void __iomem *base; + struct irq_domain *irq_domain; +}; + +static void goldfish_pic_cascade(struct irq_desc *desc) +{ + struct goldfish_pic_data *gfpic = irq_desc_get_handler_data(desc); + struct irq_chip *host_chip = irq_desc_get_chip(desc); + u32 pending, hwirq, virq; + + chained_irq_enter(host_chip, desc); + + pending = readl(gfpic->base + GFPIC_REG_IRQ_PENDING); + while (pending) { + hwirq = __fls(pending); + virq = irq_linear_revmap(gfpic->irq_domain, hwirq); + generic_handle_irq(virq); + pending &= ~(1 << hwirq); + } + + chained_irq_exit(host_chip, desc); +} + +static const struct irq_domain_ops goldfish_irq_domain_ops = { + .xlate = irq_domain_xlate_onecell, +}; + +static int __init goldfish_pic_of_init(struct device_node *of_node, + struct device_node *parent) +{ + struct goldfish_pic_data *gfpic; + struct irq_chip_generic *gc; + struct irq_chip_type *ct; + unsigned int parent_irq; + int ret = 0; + + gfpic = kzalloc(sizeof(*gfpic), GFP_KERNEL); + if (!gfpic) { + ret = -ENOMEM; + goto out_err; + } + + parent_irq = irq_of_parse_and_map(of_node, 0); + if (!parent_irq) { + pr_err("Failed to map parent IRQ!\n"); + ret = -EINVAL; + goto out_free; + } + + gfpic->base = of_iomap(of_node, 0); + if (!gfpic->base) { + pr_err("Failed to map base address!\n"); + ret = -ENOMEM; + goto out_unmap_irq; + } + + /* Mask interrupts. */ + writel(1, gfpic->base + GFPIC_REG_IRQ_DISABLE_ALL); + + gc = irq_alloc_generic_chip("GFPIC", 1, GFPIC_IRQ_BASE, gfpic->base, + handle_level_irq); + if (!gc) { + pr_err("Failed to allocate chip structures!\n"); + ret = -ENOMEM; + goto out_iounmap; + } + + ct = gc->chip_types; + ct->regs.enable = GFPIC_REG_IRQ_ENABLE; + ct->regs.disable = GFPIC_REG_IRQ_DISABLE; + ct->chip.irq_unmask = irq_gc_unmask_enable_reg; + ct->chip.irq_mask = irq_gc_mask_disable_reg; + + irq_setup_generic_chip(gc, IRQ_MSK(GFPIC_NR_IRQS), 0, + IRQ_NOPROBE | IRQ_LEVEL, 0); + + gfpic->irq_domain = irq_domain_add_legacy(of_node, GFPIC_NR_IRQS, + GFPIC_IRQ_BASE, 0, + &goldfish_irq_domain_ops, + NULL); + if (!gfpic->irq_domain) { + pr_err("Failed to add irqdomain!\n"); + ret = -ENOMEM; + goto out_destroy_generic_chip; + } + + irq_set_chained_handler_and_data(parent_irq, + goldfish_pic_cascade, gfpic); + + pr_info("Successfully registered.\n"); + return 0; + +out_destroy_generic_chip: + irq_destroy_generic_chip(gc, IRQ_MSK(GFPIC_NR_IRQS), + IRQ_NOPROBE | IRQ_LEVEL, 0); +out_iounmap: + iounmap(gfpic->base); +out_unmap_irq: + irq_dispose_mapping(parent_irq); +out_free: + kfree(gfpic); +out_err: + pr_err("Failed to initialize! (errno = %d)\n", ret); + return ret; +} + +IRQCHIP_DECLARE(google_gf_pic, "google,goldfish-pic", goldfish_pic_of_init); -- cgit v1.2.3-59-g8ed1b