/* $NetBSD: tegra_lic.c,v 1.8 2021/01/27 03:10:19 thorpej Exp $ */

/*-
 * Copyright (c) 2015 Jared D. McNeill <jmcneill@invisible.ca>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: tegra_lic.c,v 1.8 2021/01/27 03:10:19 thorpej Exp $");

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/intr.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/kmem.h>

#include <arm/nvidia/tegra_reg.h>
#include <arm/nvidia/tegra_var.h>

#include <arm/cortex/gic_intr.h>

#include <dev/fdt/fdtvar.h>

#define LIC_CPU_IER_CLR_REG     0x28
#define LIC_CPU_IEP_CLASS_REG   0x2c

static int      tegra_lic_match(device_t, cfdata_t, void *);
static void     tegra_lic_attach(device_t, device_t, void *);

static void *   tegra_lic_establish(device_t, u_int *, int, int,
                    int (*)(void *), void *, const char *);
static void     tegra_lic_disestablish(device_t, void *);
static bool     tegra_lic_intrstr(device_t, u_int *, char *, size_t);

struct fdtbus_interrupt_controller_func tegra_lic_funcs = {
        .establish = tegra_lic_establish,
        .disestablish = tegra_lic_disestablish,
        .intrstr = tegra_lic_intrstr
};

struct tegra_lic_softc {
        device_t                sc_dev;
        int                     sc_phandle;
};

CFATTACH_DECL_NEW(tegra_lic, sizeof(struct tegra_lic_softc),
        tegra_lic_match, tegra_lic_attach, NULL, NULL);

static const struct device_compatible_entry compat_data[] = {
        { .compat = "nvidia,tegra210-ictlr" },
        { .compat = "nvidia,tegra124-ictlr" },
        DEVICE_COMPAT_EOL
};

static int
tegra_lic_match(device_t parent, cfdata_t cf, void *aux)
{
        struct fdt_attach_args * const faa = aux;

        return of_compatible_match(faa->faa_phandle, compat_data);
}

static void
tegra_lic_attach(device_t parent, device_t self, void *aux)
{
        struct tegra_lic_softc * const sc = device_private(self);
        struct fdt_attach_args * const faa = aux;
        bus_space_tag_t bst;
        bus_space_handle_t bsh;
        bus_addr_t addr;
        bus_size_t size;
        int error, index;

        sc->sc_dev = self;
        sc->sc_phandle = faa->faa_phandle;

        error = fdtbus_register_interrupt_controller(self, faa->faa_phandle,
            &tegra_lic_funcs);
        if (error) {
                aprint_error(": couldn't register with fdtbus: %d\n", error);
                return;
        }

        aprint_naive("\n");
        aprint_normal(": LIC\n");

        bst = faa->faa_bst;
        for (index = 0; ; index++) {
                error = fdtbus_get_reg(faa->faa_phandle, index, &addr, &size);
                if (error != 0)
                        break;
                error = bus_space_map(bst, addr, size, 0, &bsh);
                if (error) {
                        aprint_error_dev(self, "can't map IC#%d: %d\n",
                            index, error);
                        continue;
                }

                /* Clear interrupt enable for CPU */
                bus_space_write_4(bst, bsh, LIC_CPU_IER_CLR_REG, 0xffffffff);

                /* Route to IRQ */
                bus_space_write_4(bst, bsh, LIC_CPU_IEP_CLASS_REG, 0);

                bus_space_unmap(bst, bsh, size);
        }
}

static void *
tegra_lic_establish(device_t dev, u_int *specifier, int ipl, int flags,
    int (*func)(void *), void *arg, const char *xname)
{
        int iflags = (flags & FDT_INTR_MPSAFE) ? IST_MPSAFE : 0;

        /* 1st cell is the interrupt type; 0 is SPI, 1 is PPI */
        /* 2nd cell is the interrupt number */
        /* 3rd cell is flags */

        const u_int type = be32toh(specifier[0]);
        const u_int intr = be32toh(specifier[1]);
        const u_int irq = type == 0 ? IRQ_SPI(intr) : IRQ_PPI(intr);
        const u_int trig = be32toh(specifier[2]) & 0xf;
        const u_int level = (trig & FDT_INTR_TYPE_DOUBLE_EDGE)
            ? IST_EDGE : IST_LEVEL;

        return intr_establish_xname(irq, ipl, level | iflags, func, arg,
            xname);
}

static void
tegra_lic_disestablish(device_t dev, void *ih)
{
        intr_disestablish(ih);
}

static bool
tegra_lic_intrstr(device_t dev, u_int *specifier, char *buf,
    size_t buflen)
{
        /* 1st cell is the interrupt type; 0 is SPI, 1 is PPI */
        /* 2nd cell is the interrupt number */
        /* 3rd cell is flags */

        const u_int type = be32toh(specifier[0]);
        const u_int intr = be32toh(specifier[1]);
        const u_int irq = type == 0 ? IRQ_SPI(intr) : IRQ_PPI(intr);

        snprintf(buf, buflen, "irq %d", irq);

        return true;
}