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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/irqchip/irq-goldfish-pic.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/irqchip/irq-goldfish-pic.c')
-rw-r--r-- | drivers/irqchip/irq-goldfish-pic.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-goldfish-pic.c b/drivers/irqchip/irq-goldfish-pic.c new file mode 100644 index 000000000..2a92f03c7 --- /dev/null +++ b/drivers/irqchip/irq-goldfish-pic.c @@ -0,0 +1,139 @@ +/* + * Driver for MIPS Goldfish Programmable Interrupt Controller. + * + * Author: Miodrag Dinic <miodrag.dinic@mips.com> + * + * 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 <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +#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); |