root/arch/arm/mach-pxa/irq.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/arch/arm/mach-pxa/irq.c
 *
 *  Generic PXA IRQ handling
 *
 *  Author:     Nicolas Pitre
 *  Created:    Jun 15, 2001
 *  Copyright:  MontaVista Software Inc.
 */
#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/syscore_ops.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/soc/pxa/cpu.h>

#include <asm/exception.h>

#include "irqs.h"

#include "generic.h"
#include "pxa-regs.h"

#define ICIP                    (0x000)
#define ICMR                    (0x004)
#define ICLR                    (0x008)
#define ICFR                    (0x00c)
#define ICPR                    (0x010)
#define ICCR                    (0x014)
#define ICHP                    (0x018)
#define IPR(i)                  (((i) < 32) ? (0x01c + ((i) << 2)) :            \
                                ((i) < 64) ? (0x0b0 + (((i) - 32) << 2)) :      \
                                      (0x144 + (((i) - 64) << 2)))
#define ICHP_VAL_IRQ            (1 << 31)
#define ICHP_IRQ(i)             (((i) >> 16) & 0x7fff)
#define IPR_VALID               (1 << 31)

#define MAX_INTERNAL_IRQS       128

/*
 * This is for peripheral IRQs internal to the PXA chip.
 */

static void __iomem *pxa_irq_base;
static int pxa_internal_irq_nr;
static bool cpu_has_ipr;
static struct irq_domain *pxa_irq_domain;

static inline void __iomem *irq_base(int i)
{
        static unsigned long phys_base_offset[] = {
                0x0,
                0x9c,
                0x130,
        };

        return pxa_irq_base + phys_base_offset[i];
}

void pxa_mask_irq(struct irq_data *d)
{
        void __iomem *base = irq_data_get_irq_chip_data(d);
        irq_hw_number_t irq = irqd_to_hwirq(d);
        uint32_t icmr = __raw_readl(base + ICMR);

        icmr &= ~BIT(irq & 0x1f);
        __raw_writel(icmr, base + ICMR);
}

void pxa_unmask_irq(struct irq_data *d)
{
        void __iomem *base = irq_data_get_irq_chip_data(d);
        irq_hw_number_t irq = irqd_to_hwirq(d);
        uint32_t icmr = __raw_readl(base + ICMR);

        icmr |= BIT(irq & 0x1f);
        __raw_writel(icmr, base + ICMR);
}

static struct irq_chip pxa_internal_irq_chip = {
        .name           = "SC",
        .irq_ack        = pxa_mask_irq,
        .irq_mask       = pxa_mask_irq,
        .irq_unmask     = pxa_unmask_irq,
};

asmlinkage void __exception_irq_entry icip_handle_irq(struct pt_regs *regs)
{
        uint32_t icip, icmr, mask;

        do {
                icip = __raw_readl(pxa_irq_base + ICIP);
                icmr = __raw_readl(pxa_irq_base + ICMR);
                mask = icip & icmr;

                if (mask == 0)
                        break;

                handle_IRQ(PXA_IRQ(fls(mask) - 1), regs);
        } while (1);
}

asmlinkage void __exception_irq_entry ichp_handle_irq(struct pt_regs *regs)
{
        uint32_t ichp;

        do {
                __asm__ __volatile__("mrc p6, 0, %0, c5, c0, 0\n": "=r"(ichp));

                if ((ichp & ICHP_VAL_IRQ) == 0)
                        break;

                handle_IRQ(PXA_IRQ(ICHP_IRQ(ichp)), regs);
        } while (1);
}

static int pxa_irq_map(struct irq_domain *h, unsigned int virq,
                       irq_hw_number_t hw)
{
        void __iomem *base = irq_base(hw / 32);

        /* initialize interrupt priority */
        if (cpu_has_ipr)
                __raw_writel(hw | IPR_VALID, pxa_irq_base + IPR(hw));

        irq_set_chip_and_handler(virq, &pxa_internal_irq_chip,
                                 handle_level_irq);
        irq_set_chip_data(virq, base);

        return 0;
}

static const struct irq_domain_ops pxa_irq_ops = {
        .map    = pxa_irq_map,
        .xlate  = irq_domain_xlate_onecell,
};

static __init void
pxa_init_irq_common(struct device_node *node, int irq_nr,
                    int (*fn)(struct irq_data *, unsigned int))
{
        int n;

        pxa_internal_irq_nr = irq_nr;
        pxa_irq_domain = irq_domain_create_legacy(of_fwnode_handle(node), irq_nr, PXA_IRQ(0), 0,
                                                  &pxa_irq_ops, NULL);
        if (!pxa_irq_domain)
                panic("Unable to add PXA IRQ domain\n");
        irq_set_default_domain(pxa_irq_domain);

        for (n = 0; n < irq_nr; n += 32) {
                void __iomem *base = irq_base(n >> 5);

                __raw_writel(0, base + ICMR);   /* disable all IRQs */
                __raw_writel(0, base + ICLR);   /* all IRQs are IRQ, not FIQ */
        }
        /* only unmasked interrupts kick us out of idle */
        __raw_writel(1, irq_base(0) + ICCR);

        pxa_internal_irq_chip.irq_set_wake = fn;
}

void __init pxa_init_irq(int irq_nr, int (*fn)(struct irq_data *, unsigned int))
{
        BUG_ON(irq_nr > MAX_INTERNAL_IRQS);

        pxa_irq_base = io_p2v(0x40d00000);
        cpu_has_ipr = !cpu_is_pxa25x();
        pxa_init_irq_common(NULL, irq_nr, fn);
}

#ifdef CONFIG_PM
static unsigned long saved_icmr[MAX_INTERNAL_IRQS/32];
static unsigned long saved_ipr[MAX_INTERNAL_IRQS];

static int pxa_irq_suspend(void *data)
{
        int i;

        for (i = 0; i < DIV_ROUND_UP(pxa_internal_irq_nr, 32); i++) {
                void __iomem *base = irq_base(i);

                saved_icmr[i] = __raw_readl(base + ICMR);
                __raw_writel(0, base + ICMR);
        }

        if (cpu_has_ipr) {
                for (i = 0; i < pxa_internal_irq_nr; i++)
                        saved_ipr[i] = __raw_readl(pxa_irq_base + IPR(i));
        }

        return 0;
}

static void pxa_irq_resume(void *data)
{
        int i;

        for (i = 0; i < DIV_ROUND_UP(pxa_internal_irq_nr, 32); i++) {
                void __iomem *base = irq_base(i);

                __raw_writel(saved_icmr[i], base + ICMR);
                __raw_writel(0, base + ICLR);
        }

        if (cpu_has_ipr)
                for (i = 0; i < pxa_internal_irq_nr; i++)
                        __raw_writel(saved_ipr[i], pxa_irq_base + IPR(i));

        __raw_writel(1, pxa_irq_base + ICCR);
}
#else
#define pxa_irq_suspend         NULL
#define pxa_irq_resume          NULL
#endif

static const struct syscore_ops pxa_irq_syscore_ops = {
        .suspend        = pxa_irq_suspend,
        .resume         = pxa_irq_resume,
};

struct syscore pxa_irq_syscore = {
        .ops = &pxa_irq_syscore_ops,
};

#ifdef CONFIG_OF
static const struct of_device_id intc_ids[] __initconst = {
        { .compatible = "marvell,pxa-intc", },
        {}
};

void __init pxa_dt_irq_init(int (*fn)(struct irq_data *, unsigned int))
{
        struct device_node *node;
        struct resource res;
        int ret;

        node = of_find_matching_node(NULL, intc_ids);
        if (!node) {
                pr_err("Failed to find interrupt controller in arch-pxa\n");
                return;
        }

        ret = of_property_read_u32(node, "marvell,intc-nr-irqs",
                                   &pxa_internal_irq_nr);
        if (ret) {
                pr_err("Not found marvell,intc-nr-irqs property\n");
                return;
        }

        ret = of_address_to_resource(node, 0, &res);
        if (ret < 0) {
                pr_err("No registers defined for node\n");
                return;
        }
        pxa_irq_base = io_p2v(res.start);

        cpu_has_ipr = of_property_read_bool(node, "marvell,intc-priority");

        ret = irq_alloc_descs(-1, 0, pxa_internal_irq_nr, 0);
        if (ret < 0) {
                pr_err("Failed to allocate IRQ numbers\n");
                return;
        }

        pxa_init_irq_common(node, pxa_internal_irq_nr, fn);
}
#endif /* CONFIG_OF */