/* $NetBSD: bcm2835_bsc_acpi.c,v 1.6 2025/09/15 15:31:44 thorpej Exp $ */

/*-
 * Copyright (c) 2020 Jared 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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: bcm2835_bsc_acpi.c,v 1.6 2025/09/15 15:31:44 thorpej Exp $");

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/cpu.h>
#include <sys/device.h>

#include <dev/acpi/acpireg.h>
#include <dev/acpi/acpivar.h>
#include <dev/acpi/acpi_intr.h>

#include <arm/broadcom/bcm2835var.h>
#include <arm/broadcom/bcm2835_mbox.h>
#include <arm/broadcom/bcm2835_bscvar.h>

#include <evbarm/rpi/vcio.h>
#include <evbarm/rpi/vcpm.h>
#include <evbarm/rpi/vcprop.h>

static int      bsciic_acpi_match(device_t, cfdata_t, void *);
static void     bsciic_acpi_attach(device_t, device_t, void *);

static u_int    bsciic_acpi_vpu_clock_rate(void);

CFATTACH_DECL_NEW(bsciic_acpi, sizeof(struct bsciic_softc), bsciic_acpi_match, bsciic_acpi_attach, NULL, NULL);

static const char * const compatible[] = {
        "BCM2841",
        NULL
};

static struct {
        struct vcprop_buffer_hdr        vb_hdr;
        struct vcprop_tag_clockrate     vbt_vpuclockrate;
        struct vcprop_tag end;
} vb_vpu __cacheline_aligned = {
        .vb_hdr = {
                .vpb_len = sizeof(vb_vpu),
                .vpb_rcode = VCPROP_PROCESS_REQUEST
        },
        .vbt_vpuclockrate = {
                .tag = {
                        .vpt_tag = VCPROPTAG_GET_CLOCKRATE,
                        .vpt_len = VCPROPTAG_LEN(vb_vpu.vbt_vpuclockrate),
                        .vpt_rcode = VCPROPTAG_REQUEST
                },
                .id = VCPROP_CLK_CORE
        },
        .end = {
                .vpt_tag = VCPROPTAG_NULL
        }
};

static int
bsciic_acpi_match(device_t parent, cfdata_t cf, void *aux)
{
        struct acpi_attach_args *aa = aux;

        if (aa->aa_node->ad_type != ACPI_TYPE_DEVICE)
                return 0;

        return acpi_match_hid(aa->aa_node->ad_devinfo, compatible);
}

static void
bsciic_acpi_attach(device_t parent, device_t self, void *aux)
{
        struct bsciic_softc * const sc = device_private(self);
        struct acpi_attach_args *aa = aux;
        struct acpi_resources res;
        struct acpi_mem *mem;
        struct acpi_irq *irq;
        ACPI_STATUS rv;
        ACPI_INTEGER clock_freq;
        void *ih;

        sc->sc_dev = self;

        rv = acpi_resource_parse(sc->sc_dev, aa->aa_node->ad_handle, "_CRS",
            &res, &acpi_resource_parse_ops_default);
        if (ACPI_FAILURE(rv))
                return;

        mem = acpi_res_mem(&res, 0);
        if (mem == NULL) {
                aprint_error_dev(self, "couldn't find mem resource\n");
                goto done;
        }

        irq = acpi_res_irq(&res, 0);
        if (irq == NULL) {
                aprint_error_dev(self, "couldn't find irq resource\n");
                goto done;
        }

        sc->sc_dev = self;
        sc->sc_iot = aa->aa_memt;
        if (bus_space_map(aa->aa_memt, mem->ar_base, mem->ar_length, 0, &sc->sc_ioh) != 0) {
                aprint_error_dev(self, "couldn't map registers\n");
                goto done;
        }

        sc->sc_frequency = bsciic_acpi_vpu_clock_rate();
        if (sc->sc_frequency == 0) {
                aprint_error_dev(self, "couldn't determine parent clock rate\n");
                goto done;
        }

        rv = acpi_dsd_integer(aa->aa_node->ad_handle, "clock-frequency", &clock_freq);
        if (ACPI_SUCCESS(rv))
                sc->sc_clkrate = clock_freq;
        else
                sc->sc_clkrate = 100000;

        bsciic_attach(sc);

        ih = acpi_intr_establish(self, (uint64_t)aa->aa_node->ad_handle,
            IPL_VM, true, bsciic_intr, sc, device_xname(self));
        if (ih == NULL) {
                aprint_error_dev(self, "couldn't install interrupt handler\n");
                goto done;
        }

        iic_tag_init(&sc->sc_i2c);
        sc->sc_i2c.ic_cookie = sc;
        sc->sc_i2c.ic_acquire_bus = bsciic_acquire_bus;
        sc->sc_i2c.ic_release_bus = bsciic_release_bus;
        sc->sc_i2c.ic_exec = bsciic_exec;

        iicbus_attach(self, &sc->sc_i2c);

done:
        acpi_resource_cleanup(&res);
}

static u_int
bsciic_acpi_vpu_clock_rate(void)
{
        uint32_t res;
        int error;

        error = bcmmbox_request(BCMMBOX_CHANARM2VC, &vb_vpu,
            sizeof(vb_vpu), &res);
        if (error != 0) {
                printf("%s: mbox request failed (%d)\n", __func__, error);
                return 0;
        }

        if (!vcprop_buffer_success_p(&vb_vpu.vb_hdr) ||
            !vcprop_tag_success_p(&vb_vpu.vbt_vpuclockrate.tag) ||
            vb_vpu.vbt_vpuclockrate.rate < 0)
                return 0;

        return vb_vpu.vbt_vpuclockrate.rate;
}