/*      $NetBSD: wdc_mb.c,v 1.43 2023/12/20 00:40:42 thorpej Exp $      */

/*-
 * Copyright (c) 1998, 2003 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum and by Onno van der Linden.
 *
 * 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: wdc_mb.c,v 1.43 2023/12/20 00:40:42 thorpej Exp $");

#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>

#include <sys/bswap.h>
#include <machine/cpu.h>
#include <sys/bus.h>
#include <machine/iomap.h>
#include <machine/mfp.h>
#include <machine/dma.h>

#include <dev/ata/atavar.h>
#include <dev/ic/wdcvar.h>

#include <m68k/asm_single.h>

#include <atari/dev/ym2149reg.h>
#include <atari/atari/device.h>

/* Falcon IDE register locations (base and offsets). */
#define FALCON_WD_BASE  0xfff00000
#define FALCON_WD_LEN   0x40
#define FALCON_WD_AUX   0x38

/*
 * XXX This code currently doesn't even try to allow 32-bit data port use.
 */
static int      claim_hw(struct ata_channel *, int);
static void     free_hw(struct ata_channel *);
static void     read_multi_2_swap(bus_space_tag_t, bus_space_handle_t,
                    bus_size_t, uint16_t *, bus_size_t);
static void     write_multi_2_swap(bus_space_tag_t, bus_space_handle_t,
                    bus_size_t, const uint16_t *, bus_size_t);

struct wdc_mb_softc {
        struct wdc_softc sc_wdcdev;
        struct ata_channel *sc_chanlist[1];
        struct ata_channel sc_channel;
        struct wdc_regs sc_wdc_regs;
        void *sc_ih;
};

static int      wdc_mb_probe(device_t, struct cfdata *, void *);
static void     wdc_mb_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(wdc_mb, sizeof(struct wdc_mb_softc),
    wdc_mb_probe, wdc_mb_attach, NULL, NULL);

static int
wdc_mb_probe(device_t parent, cfdata_t cfp, void *aux)
{
        static int wdc_matched = 0;
        struct wdc_regs wdr;
        int result = 0, i;
        uint8_t sv_ierb;

        if ((machineid & ATARI_TT) || strcmp("wdc", aux) || wdc_matched)
                return 0;
        if (!atari_realconfig)
                return 0;

        wdr.cmd_iot = wdr.ctl_iot = mb_alloc_bus_space_tag();
        if (wdr.cmd_iot == NULL)
                return 0;
        wdr.cmd_iot->stride = 0;
        wdr.cmd_iot->wo_1   = 1;

        if (bus_space_map(wdr.cmd_iot, FALCON_WD_BASE, FALCON_WD_LEN, 0,
            &wdr.cmd_baseioh))
                goto out;
        for (i = 0; i < WDC_NREG; i++) {
                if (bus_space_subregion(wdr.cmd_iot, wdr.cmd_baseioh,
                    i * 4, 4, &wdr.cmd_iohs[i]) != 0)
                        goto outunmap;
        }
        wdc_init_shadow_regs(&wdr);

        if (bus_space_subregion(wdr.cmd_iot, wdr.cmd_baseioh, FALCON_WD_AUX, 4,
            &wdr.ctl_ioh))
                goto outunmap;

        /*
         * Make sure IDE interrupts are disabled during probing.
         */
        sv_ierb = MFP->mf_ierb;
        MFP->mf_ierb &= ~IB_DINT;

        /*
         * Make sure that IDE is turned on on the Falcon.
         */
        if (machineid & ATARI_FALCON)
                ym2149_ser2(0);

        result = wdcprobe(&wdr);

        MFP->mf_ierb = sv_ierb;

 outunmap:
        bus_space_unmap(wdr.cmd_iot, wdr.cmd_baseioh, FALCON_WD_LEN);
 out:
        mb_free_bus_space_tag(wdr.cmd_iot);

        if (result)
                wdc_matched = 1;
        return result;
}

static void
wdc_mb_attach(device_t parent, device_t self, void *aux)
{
        struct wdc_mb_softc *sc = device_private(self);
        struct wdc_regs *wdr;
        int i;

        aprint_normal("\n");

        sc->sc_wdcdev.sc_atac.atac_dev = self;
        sc->sc_wdcdev.regs = wdr = &sc->sc_wdc_regs;
        wdr->cmd_iot = wdr->ctl_iot =
            mb_alloc_bus_space_tag();
        wdr->cmd_iot->stride = 0;
        wdr->cmd_iot->wo_1   = 1;
        wdr->cmd_iot->abs_rms_2 = read_multi_2_swap;
        wdr->cmd_iot->abs_wms_2 = write_multi_2_swap;
        if (bus_space_map(wdr->cmd_iot, FALCON_WD_BASE, FALCON_WD_LEN, 0,
                          &wdr->cmd_baseioh)) {
                aprint_error_dev(self, "couldn't map registers\n");
                return;
        }
        for (i = 0; i < WDC_NREG; i++) {
                if (bus_space_subregion(wdr->cmd_iot, wdr->cmd_baseioh,
                    i * 4, 4, &wdr->cmd_iohs[i]) != 0) {
                        aprint_error_dev(self,
                            "couldn't subregion cmd reg %i\n", i);
                        bus_space_unmap(wdr->cmd_iot, wdr->cmd_baseioh,
                            FALCON_WD_LEN);
                        return;
                }
        }

        if (bus_space_subregion(wdr->cmd_iot,
            wdr->cmd_baseioh, FALCON_WD_AUX, 4, &wdr->ctl_ioh)) {
                bus_space_unmap(wdr->cmd_iot, wdr->cmd_baseioh, FALCON_WD_LEN);
                aprint_error_dev(self, "couldn't subregion aux reg\n");
                return;
        }

        /*
         * Play a nasty trick here. Normally we only manipulate the
         * interrupt *mask*. However to defeat wd_get_parms(), we
         * disable the interrupts here using the *enable* register.
         */
        MFP->mf_ierb &= ~IB_DINT;

        sc->sc_wdcdev.sc_atac.atac_cap |= ATAC_CAP_DATA16 |
            ATAC_CAP_ATA_NOSTREAM;
        sc->sc_wdcdev.sc_atac.atac_pio_cap = 0;
        sc->sc_wdcdev.sc_atac.atac_claim_hw = &claim_hw;
        sc->sc_wdcdev.sc_atac.atac_free_hw  = &free_hw;
        sc->sc_chanlist[0] = &sc->sc_channel;
        sc->sc_wdcdev.sc_atac.atac_channels = sc->sc_chanlist;
        sc->sc_wdcdev.sc_atac.atac_nchannels = 1;
        sc->sc_wdcdev.wdc_maxdrives = 2;
        sc->sc_channel.ch_channel = 0;
        sc->sc_channel.ch_atac = &sc->sc_wdcdev.sc_atac;

        wdc_init_shadow_regs(wdr);

        /*
         * Setup & enable disk related interrupts.
         */
        MFP->mf_ierb |= IB_DINT;
        MFP->mf_iprb  = (uint8_t)~IB_DINT;
        MFP->mf_imrb |= IB_DINT;

        wdcattach(&sc->sc_channel);
}

/*
 * Hardware locking
 */
static int      wd_lock;

static int
claim_hw(struct ata_channel *chp, int maysleep)
{
        ata_channel_lock_owned(chp);

        if (wd_lock != DMA_LOCK_GRANT) {
                if (wd_lock == DMA_LOCK_REQ) {
                        /*
                         * ST_DMA access is being claimed.
                         */
                        return 0;
                }
                if (!st_dmagrab((dma_farg)wdcintr,
                    (dma_farg)(maysleep ? NULL : wdcrestart), chp,
                    &wd_lock, 1, &chp->ch_lock))
                        return 0;
        }
        return 1;
}

static void
free_hw(struct ata_channel *chp)
{
        ata_channel_lock_owned(chp);

        /*
         * Flush pending interrupts before giving-up lock
         */
        MFP->mf_iprb = (uint8_t)~IB_DINT;

        /*
         * Only free the lock on a Falcon. On the Hades, keep it.
         */
/*      if (machineid & ATARI_FALCON) */
                st_dmafree(chp, &wd_lock);
}

/*
 * XXX
 * This piece of uglyness is caused by the fact that the byte lanes of
 * the data-register are swapped on the atari. This works OK for an IDE
 * disk, but turns into a nightmare when used on atapi devices.
 */
#define calc_addr(base, off, stride, wm)        \
        ((u_long)(base) + ((off) << (stride)) + (wm))

static void
read_multi_2_swap(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o,
    uint16_t *a, bus_size_t c)
{
        volatile uint16_t *ba;

        ba = (volatile uint16_t *)calc_addr(h, o, t->stride, t->wo_2);
        for (; c; a++, c--)
                *a = bswap16(*ba);
}

static void
write_multi_2_swap(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o,
    const uint16_t *a, bus_size_t c)
{
        volatile uint16_t *ba;

        ba = (volatile uint16_t *)calc_addr(h, o, t->stride, t->wo_2);
        for (; c; a++, c--)
                *ba = bswap16(*a);
}