/* $NetBSD: tegra_fuse.c,v 1.9 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_fuse.c,v 1.9 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 <arm/nvidia/tegra_reg.h>
#include <arm/nvidia/tegra_var.h>

#include <dev/fdt/fdtvar.h>

static int      tegra_fuse_match(device_t, cfdata_t, void *);
static void     tegra_fuse_attach(device_t, device_t, void *);

struct tegra_fuse_softc {
        device_t                sc_dev;
        bus_space_tag_t         sc_bst;
        bus_space_handle_t      sc_bsh;

        struct clk              *sc_clk;
        struct fdtbus_reset     *sc_rst;
};

static struct tegra_fuse_softc *fuse_softc = NULL;

CFATTACH_DECL_NEW(tegra_fuse, sizeof(struct tegra_fuse_softc),
        tegra_fuse_match, tegra_fuse_attach, NULL, NULL);

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

static int
tegra_fuse_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_fuse_attach(device_t parent, device_t self, void *aux)
{
        struct tegra_fuse_softc * const sc = device_private(self);
        struct fdt_attach_args * const faa = aux;
        bus_addr_t addr;
        bus_size_t size;
        int error;

        if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) {
                aprint_error(": couldn't get registers\n");
                return;
        }
        sc->sc_clk = fdtbus_clock_get(faa->faa_phandle, "fuse");
        if (sc->sc_clk == NULL) {
                aprint_error(": couldn't get clock fuse\n");
                return;
        }
        sc->sc_rst = fdtbus_reset_get(faa->faa_phandle, "fuse");
        if (sc->sc_rst == NULL) {
                aprint_error(": couldn't get reset fuse\n");
                return;
        }

        sc->sc_dev = self;
        sc->sc_bst = faa->faa_bst;
        error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
        if (error) {
                aprint_error(": couldn't map %#" PRIxBUSADDR ": %d", addr, error);
                return;
        }

        KASSERT(fuse_softc == NULL);
        fuse_softc = sc;

        aprint_naive("\n");
        aprint_normal(": FUSE\n");
}

uint32_t
tegra_fuse_read(u_int offset)
{
        bus_space_tag_t bst;
        bus_space_handle_t bsh;

        KASSERT(fuse_softc != NULL);

        bst = fuse_softc->sc_bst;
        bsh = fuse_softc->sc_bsh;

        clk_enable(fuse_softc->sc_clk);
        const uint32_t v = bus_space_read_4(bst, bsh, 0x100 + offset);
        clk_disable(fuse_softc->sc_clk);

        return v;
}