root/drivers/irqchip/irq-mtk-sysirq.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2014 MediaTek Inc.
 * Author: Joe.C <yingjoe.chen@mediatek.com>
 */

#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

struct mtk_sysirq_chip_data {
        raw_spinlock_t lock;
        u32 nr_intpol_bases;
        void __iomem **intpol_bases;
        u32 *intpol_words;
        u8 *intpol_idx;
        u16 *which_word;
};

static int mtk_sysirq_set_type(struct irq_data *data, unsigned int type)
{
        irq_hw_number_t hwirq = data->hwirq;
        struct mtk_sysirq_chip_data *chip_data = data->chip_data;
        u8 intpol_idx = chip_data->intpol_idx[hwirq];
        void __iomem *base;
        u32 offset, reg_index, value;
        unsigned long flags;
        int ret;

        base = chip_data->intpol_bases[intpol_idx];
        reg_index = chip_data->which_word[hwirq];
        offset = hwirq & 0x1f;

        raw_spin_lock_irqsave(&chip_data->lock, flags);
        value = readl_relaxed(base + reg_index * 4);
        if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING) {
                if (type == IRQ_TYPE_LEVEL_LOW)
                        type = IRQ_TYPE_LEVEL_HIGH;
                else
                        type = IRQ_TYPE_EDGE_RISING;
                value |= (1 << offset);
        } else {
                value &= ~(1 << offset);
        }

        writel_relaxed(value, base + reg_index * 4);

        data = data->parent_data;
        ret = data->chip->irq_set_type(data, type);
        raw_spin_unlock_irqrestore(&chip_data->lock, flags);
        return ret;
}

static struct irq_chip mtk_sysirq_chip = {
        .name                   = "MT_SYSIRQ",
        .irq_mask               = irq_chip_mask_parent,
        .irq_unmask             = irq_chip_unmask_parent,
        .irq_eoi                = irq_chip_eoi_parent,
        .irq_set_type           = mtk_sysirq_set_type,
        .irq_retrigger          = irq_chip_retrigger_hierarchy,
        .irq_set_affinity       = irq_chip_set_affinity_parent,
        .flags                  = IRQCHIP_SKIP_SET_WAKE,
};

static int mtk_sysirq_domain_translate(struct irq_domain *d,
                                       struct irq_fwspec *fwspec,
                                       unsigned long *hwirq,
                                       unsigned int *type)
{
        if (is_of_node(fwspec->fwnode)) {
                if (fwspec->param_count != 3)
                        return -EINVAL;

                /* No PPI should point to this domain */
                if (fwspec->param[0] != 0)
                        return -EINVAL;

                *hwirq = fwspec->param[1];
                *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
                return 0;
        }

        return -EINVAL;
}

static int mtk_sysirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
                                   unsigned int nr_irqs, void *arg)
{
        int i;
        irq_hw_number_t hwirq;
        struct irq_fwspec *fwspec = arg;
        struct irq_fwspec gic_fwspec = *fwspec;

        if (fwspec->param_count != 3)
                return -EINVAL;

        /* sysirq doesn't support PPI */
        if (fwspec->param[0])
                return -EINVAL;

        hwirq = fwspec->param[1];
        for (i = 0; i < nr_irqs; i++)
                irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
                                              &mtk_sysirq_chip,
                                              domain->host_data);

        gic_fwspec.fwnode = domain->parent->fwnode;
        return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_fwspec);
}

static const struct irq_domain_ops sysirq_domain_ops = {
        .translate      = mtk_sysirq_domain_translate,
        .alloc          = mtk_sysirq_domain_alloc,
        .free           = irq_domain_free_irqs_common,
};

static int __init mtk_sysirq_of_init(struct device_node *node,
                                     struct device_node *parent)
{
        struct irq_domain *domain, *domain_parent;
        struct mtk_sysirq_chip_data *chip_data;
        int ret, size, intpol_num = 0, nr_intpol_bases = 0, i = 0;

        domain_parent = irq_find_host(parent);
        if (!domain_parent) {
                pr_err("mtk_sysirq: interrupt-parent not found\n");
                return -EINVAL;
        }

        chip_data = kzalloc_obj(*chip_data);
        if (!chip_data)
                return -ENOMEM;

        while (of_get_address(node, i++, NULL, NULL))
                nr_intpol_bases++;

        if (nr_intpol_bases == 0) {
                pr_err("mtk_sysirq: base address not specified\n");
                ret = -EINVAL;
                goto out_free_chip;
        }

        chip_data->intpol_words = kcalloc(nr_intpol_bases,
                                          sizeof(*chip_data->intpol_words),
                                          GFP_KERNEL);
        if (!chip_data->intpol_words) {
                ret = -ENOMEM;
                goto out_free_chip;
        }

        chip_data->intpol_bases = kzalloc_objs(*chip_data->intpol_bases,
                                               nr_intpol_bases);
        if (!chip_data->intpol_bases) {
                ret = -ENOMEM;
                goto out_free_intpol_words;
        }

        for (i = 0; i < nr_intpol_bases; i++) {
                struct resource res;

                ret = of_address_to_resource(node, i, &res);
                size = resource_size(&res);
                intpol_num += size * 8;
                chip_data->intpol_words[i] = size / 4;
                chip_data->intpol_bases[i] = of_iomap(node, i);
                if (ret || !chip_data->intpol_bases[i]) {
                        pr_err("%pOF: couldn't map region %d\n", node, i);
                        ret = -ENODEV;
                        goto out_free_intpol;
                }
        }

        chip_data->intpol_idx = kcalloc(intpol_num,
                                        sizeof(*chip_data->intpol_idx),
                                        GFP_KERNEL);
        if (!chip_data->intpol_idx) {
                ret = -ENOMEM;
                goto out_free_intpol;
        }

        chip_data->which_word = kcalloc(intpol_num,
                                        sizeof(*chip_data->which_word),
                                        GFP_KERNEL);
        if (!chip_data->which_word) {
                ret = -ENOMEM;
                goto out_free_intpol_idx;
        }

        /*
         * assign an index of the intpol_bases for each irq
         * to set it fast later
         */
        for (i = 0; i < intpol_num ; i++) {
                u32 word = i / 32, j;

                for (j = 0; word >= chip_data->intpol_words[j] ; j++)
                        word -= chip_data->intpol_words[j];

                chip_data->intpol_idx[i] = j;
                chip_data->which_word[i] = word;
        }

        domain = irq_domain_create_hierarchy(domain_parent, 0, intpol_num, of_fwnode_handle(node),
                                             &sysirq_domain_ops, chip_data);
        if (!domain) {
                ret = -ENOMEM;
                goto out_free_which_word;
        }
        raw_spin_lock_init(&chip_data->lock);

        return 0;

out_free_which_word:
        kfree(chip_data->which_word);
out_free_intpol_idx:
        kfree(chip_data->intpol_idx);
out_free_intpol:
        for (i = 0; i < nr_intpol_bases; i++)
                if (chip_data->intpol_bases[i])
                        iounmap(chip_data->intpol_bases[i]);
        kfree(chip_data->intpol_bases);
out_free_intpol_words:
        kfree(chip_data->intpol_words);
out_free_chip:
        kfree(chip_data);
        return ret;
}
IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);