/* $NetBSD: tegra_pmc.c,v 1.16 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_pmc.c,v 1.16 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_pmcreg.h>
#include <arm/nvidia/tegra_var.h>

#include <dev/fdt/fdtvar.h>

static int      tegra_pmc_match(device_t, cfdata_t, void *);
static void     tegra_pmc_attach(device_t, device_t, void *);

struct tegra_pmc_softc {
        device_t                sc_dev;
        bus_space_tag_t         sc_bst;
        bus_space_handle_t      sc_bsh;
};

static struct tegra_pmc_softc *pmc_softc = NULL;

CFATTACH_DECL_NEW(tegra_pmc, sizeof(struct tegra_pmc_softc),
        tegra_pmc_match, tegra_pmc_attach, NULL, NULL);

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

static int
tegra_pmc_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_pmc_attach(device_t parent, device_t self, void *aux)
{
        struct tegra_pmc_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_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(pmc_softc == NULL);
        pmc_softc = sc;

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

static void
tegra_pmc_get_bs(bus_space_tag_t *pbst, bus_space_handle_t *pbsh)
{
        if (pmc_softc) {
                *pbst = pmc_softc->sc_bst;
                *pbsh = pmc_softc->sc_bsh;
        } else {
                extern struct bus_space arm_generic_bs_tag;

                *pbst = &arm_generic_bs_tag;

                bus_space_subregion(*pbst, tegra_apb_bsh,
                    TEGRA_PMC_OFFSET, TEGRA_PMC_SIZE, pbsh);
        }
}

void
tegra_pmc_reset(void)
{
        bus_space_tag_t bst;
        bus_space_handle_t bsh;
        uint32_t cntrl;

        tegra_pmc_get_bs(&bst, &bsh);

        cntrl = bus_space_read_4(bst, bsh, PMC_CNTRL_0_REG);
        cntrl |= PMC_CNTRL_0_MAIN_RST;
        bus_space_write_4(bst, bsh, PMC_CNTRL_0_REG, cntrl);

        for (;;) {
                __asm("wfi");
        }
}

void
tegra_pmc_power(u_int partid, bool enable)
{
        bus_space_tag_t bst;
        bus_space_handle_t bsh;
        uint32_t status, toggle;
        bool state;
        int retry = 10000;

        tegra_pmc_get_bs(&bst, &bsh);

        status = bus_space_read_4(bst, bsh, PMC_PWRGATE_STATUS_0_REG);
        state = !!(status & __BIT(partid));
        if (state == enable)
                return;

        while (--retry > 0) {
                toggle = bus_space_read_4(bst, bsh, PMC_PWRGATE_TOGGLE_0_REG);
                if ((toggle & PMC_PWRGATE_TOGGLE_0_START) == 0)
                        break;
                delay(1);
        }
        if (retry == 0) {
                printf("ERROR: Couldn't enable PMC partition %#x\n", partid);
                return;
        }

        bus_space_write_4(bst, bsh, PMC_PWRGATE_TOGGLE_0_REG,
            __SHIFTIN(partid, PMC_PWRGATE_TOGGLE_0_PARTID) |
            PMC_PWRGATE_TOGGLE_0_START);
}

void
tegra_pmc_remove_clamping(u_int partid)
{
        bus_space_tag_t bst;
        bus_space_handle_t bsh;

        tegra_pmc_get_bs(&bst, &bsh);

        if (partid == PMC_PARTID_TD) {
                /*
                 * On Tegra124 and later, the GPU power clamping is
                 * controlled by a separate register
                 */
                bus_space_write_4(bst, bsh, PMC_GPU_RG_CNTRL_REG, 0);
                return;
        }

        bus_space_write_4(bst, bsh, PMC_REMOVE_CLAMPING_CMD_0_REG,
            __BIT(partid));
}

void
tegra_pmc_hdmi_enable(void)
{
        bus_space_tag_t bst;
        bus_space_handle_t bsh;

        tegra_pmc_get_bs(&bst, &bsh);

        tegra_reg_set_clear(bst, bsh, PMC_IO_DPD_STATUS_REG,
            0, PMC_IO_DPD_STATUS_HDMI);
        tegra_reg_set_clear(bst, bsh, PMC_IO_DPD2_STATUS_REG,
            0, PMC_IO_DPD2_STATUS_HV);
}