/*      $NetBSD: ebus.c,v 1.42 2022/01/22 11:49:16 thorpej Exp $ */

/*
 * Copyright (c) 1999, 2000 Matthew R. Green
 * 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.
 */

/*
 * EBus support for PCI based SPARC systems (ms-IIep, Ultra).
 * EBus is documented in PCIO manual (Sun Part#: 802-7837-01).
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ebus.c,v 1.42 2022/01/22 11:49:16 thorpej Exp $");

#if defined(DEBUG) && !defined(EBUS_DEBUG)
#define EBUS_DEBUG
#endif

#ifdef EBUS_DEBUG
#define EDB_PROM        0x01
#define EDB_CHILD       0x02
#define EDB_INTRMAP     0x04
#define EDB_BUSMAP      0x08
#define EDB_BUSDMA      0x10
#define EDB_INTR        0x20
int ebus_debug = 0;
#define DPRINTF(l, s)   do { if (ebus_debug & l) printf s; } while (0)
#else
#define DPRINTF(l, s)
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/kmem.h>
#include <sys/callout.h>
#include <sys/kernel.h>

#define _SPARC_BUS_DMA_PRIVATE
#include <sys/bus.h>
#include <machine/autoconf.h>

#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcidevs.h>

#include <dev/ofw/ofw_pci.h>

#include <dev/ebus/ebusreg.h>
#include <dev/ebus/ebusvar.h>

#include "opt_blink.h"

volatile uint32_t *ebus_LED = NULL;

#ifdef BLINK
static callout_t ebus_blink_ch;
static void ebus_blink(void *);
#endif

struct ebus_softc {
        device_t                        sc_dev;
        device_t                        sc_parent;      /* PCI bus */

        int                             sc_node;        /* PROM node */

        bus_space_tag_t                 sc_bustag;      /* mem tag from pci */

        /*
         * "reg" contains exactly the info we'd get by processing
         * "ranges", so don't bother with "ranges" and use "reg" directly.
         */
        struct ofw_pci_register         *sc_reg;
        int                             sc_nreg;
};

static int      ebus_match(device_t, cfdata_t, void *);
static void     ebus_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(ebus, sizeof(struct ebus_softc),
    ebus_match, ebus_attach, NULL, NULL);

static int      ebus_setup_attach_args(struct ebus_softc *, bus_space_tag_t,
                                bus_dma_tag_t, int, struct ebus_attach_args *);
static void     ebus_destroy_attach_args(struct ebus_attach_args *);
static int      ebus_print(void *, const char *);

/*
 * here are our bus space and bus DMA routines.
 */
static paddr_t  ebus_bus_mmap(bus_space_tag_t, bus_addr_t, off_t, int, int);
static int      _ebus_bus_map(bus_space_tag_t, bus_addr_t, bus_size_t, int,
                              vaddr_t, bus_space_handle_t *);
static void     *ebus_intr_establish(bus_space_tag_t, int, int,
                                     int (*)(void *), void *, void (*)(void));

static bus_dma_tag_t    ebus_alloc_dma_tag(struct ebus_softc *, bus_dma_tag_t);


/*
 * Working around PROM bogosity.
 *
 * EBus doesn't have official OFW binding.  sparc64 has a de-facto
 * standard but patching it in in prompatch.c and then decoding it
 * here would be an overkill for ms-IIep.
 *
 * So we assume that all ms-IIep based systems use PCIO chip only in
 * "motherboard mode" with interrupt lines wired directly to ms-IIep
 * interrupt inputs.
 *
 * Note that this is ineligible for prompatch.c, as we are not
 * correcting PROM to conform to some established standard, this hack
 * is tied to this version of ebus driver and as such it's better stay
 * private to the driver.
 */

struct msiiep_ebus_intr_wiring {
        const char *name;       /* PROM node */
        int line;               /* ms-IIep interrupt input */
};

static const struct msiiep_ebus_intr_wiring krups_ebus_intr_wiring[] = {
        { "su", 0 }, { "8042", 0 }, { "sound", 3 }
};

static const struct msiiep_ebus_intr_wiring espresso_ebus_intr_wiring[] = {
        { "su", 0 }, { "8042", 0 }, { "sound", 3 }, { "parallel", 4 }
};


struct msiiep_known_ebus_wiring {
        const char *model;
        const struct msiiep_ebus_intr_wiring *map;
        int mapsize;
};

#define MSIIEP_MODEL_WIRING(name, map) \
        { name, map, sizeof(map)/sizeof(map[0]) }

static const struct msiiep_known_ebus_wiring known_models[] = {
        MSIIEP_MODEL_WIRING("SUNW,501-4267", krups_ebus_intr_wiring),
        MSIIEP_MODEL_WIRING("SUNW,375-0059", espresso_ebus_intr_wiring),
        { NULL, NULL, 0}
};


/*
 * XXX: This assumes single EBus.  However I don't think any ms-IIep
 * system ever used more than one.  In any case, without looking at a
 * system with multiple PCIO chips I don't know how to correctly
 * program the driver to handle PROM glitches in them, so for the time
 * being just use globals.
 */
static const struct msiiep_ebus_intr_wiring *wiring_map;
static int wiring_map_size;

static int ebus_init_wiring_table(struct ebus_softc *);


static int
ebus_match(device_t parent, cfdata_t cf, void *aux)
{
        struct pci_attach_args *pa = aux;
        char name[10];
        int node;

        /* Only attach if there's a PROM node. */
        node = PCITAG_NODE(pa->pa_tag);
        if (node == -1)
                return (0);

        prom_getpropstringA(node, "name", name, sizeof name);
        if (PCI_CLASS(pa->pa_class) == PCI_CLASS_BRIDGE
            && PCI_VENDOR(pa->pa_id) == PCI_VENDOR_SUN
            && PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_SUN_EBUS
            && strcmp(name, "ebus") == 0)
                return (1);

        return (0);
}


static int
ebus_init_wiring_table(struct ebus_softc *sc)
{
        const struct msiiep_known_ebus_wiring *p;
        char buf[32];
        char *model;

        if (wiring_map != NULL) {
                printf("%s: global ebus wiring map already initialized\n",
                    device_xname(sc->sc_dev));
                return (0);
        }

        model = prom_getpropstringA(prom_findroot(), "model",
                                    buf, sizeof(buf));
        if (model == NULL)
                panic("ebus_init_wiring_table: no \"model\" property");

        for (p = known_models; p->model != NULL; ++p)
                if (strcmp(model, p->model) == 0) {
                        wiring_map = p->map;
                        wiring_map_size = p->mapsize;
                        return (1);
                }

        /* not found?  we should have failed in pci_attach_hook then. */
        panic("ebus_init_wiring_table: unknown model %s", model);
}


/*
 * attach an ebus and all its children.  this code is modeled
 * after the sbus code which does similar things.
 */
static void
ebus_attach(device_t parent, device_t self, void *aux)
{
        struct ebus_softc *sc = device_private(self);
        struct pci_attach_args *pa = aux;
        struct ebus_attach_args ea;
        bus_space_tag_t sbt;
        bus_dma_tag_t dmatag;
        bus_space_handle_t hLED;
        pcireg_t base14;
        int node, error;
        char devinfo[256];

        sc->sc_dev = self;

#ifdef BLINK
        callout_init(&ebus_blink_ch, 0);
#endif

        pci_devinfo(pa->pa_id, pa->pa_class, 0, devinfo, sizeof(devinfo));
        printf(": %s, revision 0x%02x\n",
               devinfo, PCI_REVISION(pa->pa_class));

        node = PCITAG_NODE(pa->pa_tag);
        if (node == -1)
                panic("%s: unable to find ebus node", device_xname(self));

        if (ebus_init_wiring_table(sc) == 0)
                return;

        /* map the LED register */
        base14 = pci_conf_read(pa->pa_pc, pa->pa_tag, 0x14);
        if (bus_space_map(pa->pa_memt, base14 + 0x726000, 4, 0, &hLED) == 0) {
                ebus_LED = bus_space_vaddr(pa->pa_memt, hLED);
#ifdef BLINK
                ebus_blink((void *)0);
#endif
        } else {
                printf("unable to map the LED register\n");
        }

        sc->sc_node = node;
        sc->sc_parent = parent; /* XXX: unused so far */
        sc->sc_bustag = pa->pa_memt; /* EBus only does PCI MEM32 space */

        if ((sbt = bus_space_tag_alloc(sc->sc_bustag, sc)) == NULL)
                panic("unable to allocate ebus bus tag");

        sbt->sparc_bus_map = _ebus_bus_map;
        sbt->sparc_bus_mmap = ebus_bus_mmap;
        sbt->sparc_intr_establish = ebus_intr_establish;

        dmatag = ebus_alloc_dma_tag(sc, pa->pa_dmat);

        /*
         * Setup ranges.  The interesting thing is that we use "reg"
         * not "ranges", since "reg" on ebus has exactly the data we'd
         * get by processing "ranges".
         */
        error = prom_getprop(node, "reg", sizeof(struct ofw_pci_register),
                             &sc->sc_nreg, &sc->sc_reg);
        if (error)
                panic("%s: unable to read ebus registers (error %d)",
                    device_xname(self), error);

        /*
         * now attach all our children
         */
        DPRINTF(EDB_CHILD, ("ebus node %08x, searching children...\n", node));
        devhandle_t selfh = device_handle(self);
        for (node = firstchild(node); node; node = nextsibling(node)) {
                char *name = prom_getpropstring(node, "name");

                if (ebus_setup_attach_args(sc, sbt, dmatag, node, &ea) != 0) {
                        printf("ebus_attach: %s: incomplete\n", name);
                        continue;
                }
                DPRINTF(EDB_CHILD,
                        ("- found child `%s', attaching\n", ea.ea_name));
                (void)config_found(self, &ea, ebus_print,
                    CFARGS(.devhandle = prom_node_to_devhandle(selfh, node)));
                ebus_destroy_attach_args(&ea);
        }
}

static int
ebus_setup_attach_args(struct ebus_softc *sc,
                       bus_space_tag_t bustag, bus_dma_tag_t dmatag, int node,
                       struct ebus_attach_args  *ea)
{
        int n, err;

        memset(ea, 0, sizeof(struct ebus_attach_args));

        err = prom_getprop(node, "name", 1, &n, &ea->ea_name);
        if (err != 0)
                return (err);
        KASSERT(ea->ea_name[n-1] == '\0');

        ea->ea_node = node;
        ea->ea_bustag = bustag;
        ea->ea_dmatag = dmatag;

        err = prom_getprop(node, "reg", sizeof(struct ebus_regs),
                           &ea->ea_nreg, &ea->ea_reg);
        if (err != 0)
                return (err);

        /*
         * On Ultra the bar is the _offset_ of the BAR in PCI config
         * space but in (some?) ms-IIep systems (e.g. Krups) it's the
         * _number_ of the BAR - e.g. BAR1 is represented by 1 in
         * Krups PROM, while on Ultra it's 0x14.  Fix it here.
         */
        for (n = 0; n < ea->ea_nreg; ++n)
            if (ea->ea_reg[n].hi < PCI_MAPREG_START) {
                ea->ea_reg[n].hi = PCI_MAPREG_START
                    + ea->ea_reg[n].hi * sizeof(pcireg_t);
            }

        err = prom_getprop(node, "address", sizeof(uint32_t),
                           &ea->ea_nvaddr, &ea->ea_vaddr);
        if (err != ENOENT) {
                if (err != 0)
                        return (err);

                if (ea->ea_nreg != ea->ea_nvaddr)
                        printf("ebus loses: device %s: %d regs and %d addrs\n",
                               ea->ea_name, ea->ea_nreg, ea->ea_nvaddr);
        } else
                ea->ea_nvaddr = 0;

        /* XXX: "interrupts" hack */
        for (n = 0; n < wiring_map_size; ++n) {
                const struct msiiep_ebus_intr_wiring *w = &wiring_map[n];
                if (strcmp(w->name, ea->ea_name) == 0) {
                        ea->ea_intr = malloc(sizeof(uint32_t),
                                             M_DEVBUF, M_WAITOK);
                        ea->ea_intr[0] = w->line;
                        ea->ea_nintr = 1;
                        break;
                }
        }

        return (0);
}

static void
ebus_destroy_attach_args(struct ebus_attach_args *ea)
{

        if (ea->ea_name)
                free((void *)ea->ea_name, M_DEVBUF);
        if (ea->ea_reg)
                free((void *)ea->ea_reg, M_DEVBUF);
        if (ea->ea_intr)
                free((void *)ea->ea_intr, M_DEVBUF);
        if (ea->ea_vaddr)
                free((void *)ea->ea_vaddr, M_DEVBUF);
}

static int
ebus_print(void *aux, const char *p)
{
        struct ebus_attach_args *ea = aux;
        int i;

        if (p)
                aprint_normal("%s at %s", ea->ea_name, p);
        for (i = 0; i < ea->ea_nreg; ++i)
                aprint_normal("%s bar %x offset 0x%x", i == 0 ? "" : ",",
                       ea->ea_reg[i].hi, ea->ea_reg[i].lo);
        for (i = 0; i < ea->ea_nintr; ++i)
                aprint_normal(" line %d", ea->ea_intr[i]);
        return (UNCONF);
}


/*
 * bus space and bus DMA methods below here
 */
static bus_dma_tag_t
ebus_alloc_dma_tag(struct ebus_softc *sc, bus_dma_tag_t pdt)
{
        bus_dma_tag_t dt;

        dt = kmem_zalloc(sizeof(*dt), KM_SLEEP);
        dt->_cookie = sc;
#define PCOPY(x)        dt->x = pdt->x
        PCOPY(_dmamap_create);
        PCOPY(_dmamap_destroy);
        PCOPY(_dmamap_load);
        PCOPY(_dmamap_load_mbuf);
        PCOPY(_dmamap_load_uio);
        PCOPY(_dmamap_load_raw);
        PCOPY(_dmamap_unload);
        PCOPY(_dmamap_sync);
        PCOPY(_dmamem_alloc);
        PCOPY(_dmamem_free);
        PCOPY(_dmamem_map);
        PCOPY(_dmamem_unmap);
        PCOPY(_dmamem_mmap);
#undef  PCOPY
        return (dt);
}

/*
 * bus space support.  <sparc64/dev/psychoreg.h> has a discussion
 * about PCI physical addresses, which also applies to ebus.
 */
static int
_ebus_bus_map(bus_space_tag_t t, bus_addr_t ba, bus_size_t size, int flags,
              vaddr_t va, bus_space_handle_t *hp)
{
        struct ebus_softc *sc = t->cookie;
        u_int bar;
        paddr_t offset;
        int i;

        bar = BUS_ADDR_IOSPACE(ba);
        offset = BUS_ADDR_PADDR(ba);

        DPRINTF(EDB_BUSMAP,
                ("\n_ebus_bus_map: bar %d offset %08x sz %x flags %x va %p\n",
                 (int)bar, (uint32_t)offset, (uint32_t)size,
                 flags, (void *)va));

        /* EBus has only two BARs */
        if (PCI_MAPREG_NUM(bar) > 1) {
                DPRINTF(EDB_BUSMAP,
                        ("\n_ebus_bus_map: impossible bar\n"));
                return (EINVAL);
        }

        /*
         * Almost all of the interesting ebus children are mapped by
         * BAR1, the last entry in sc_reg[], so work our way backwards.
         */
        for (i = sc->sc_nreg - 1; i >= 0; --i) {
                bus_addr_t pciaddr;
                uint32_t ss;

                /* EBus only does MEM32 */
                ss  = sc->sc_reg[i].phys_hi & OFW_PCI_PHYS_HI_SPACEMASK;
                if (ss != OFW_PCI_PHYS_HI_SPACE_MEM32)
                        continue;

                if (bar != (sc->sc_reg[i].phys_hi
                            & OFW_PCI_PHYS_HI_REGISTERMASK))
                        continue;

                pciaddr = (bus_addr_t)sc->sc_reg[i].phys_lo + offset;

                if (pciaddr + size > sc->sc_reg[i].phys_lo
                                        + sc->sc_reg[i].size_lo)
                        continue;

                DPRINTF(EDB_BUSMAP,
                        ("_ebus_bus_map: mapping to PCI addr %x\n",
                         (uint32_t)pciaddr));

                /* pass it onto the pci controller */
                return (bus_space_map2(t->parent, pciaddr, size,
                                       flags, va, hp));
        }

        DPRINTF(EDB_BUSMAP, (": FAILED\n"));
        return (EINVAL);
}

static paddr_t
ebus_bus_mmap(bus_space_tag_t t, bus_addr_t ba, off_t off, int prot, int flags)
{

        /* XXX: not implemented yet */
        return (-1);
}

/*
 * Install an interrupt handler for a EBus device.
 */
static void *
ebus_intr_establish(bus_space_tag_t t, int pri, int level,
                    int (*handler)(void *), void *arg,
                    void (*fastvec)(void))
{

        return (bus_intr_establish(t->parent, pri, level, handler, arg));
}

#ifdef BLINK

static void
ebus_blink(void *zero)
{
        register int s;

        s = splhigh();
        *ebus_LED = ~*ebus_LED;
        splx(s);
        /*
         * Blink rate is:
         *      full cycle every second if completely idle (loadav = 0)
         *      full cycle every 2 seconds if loadav = 1
         *      full cycle every 3 seconds if loadav = 2
         * etc.
         */
        s = (((averunnable.ldavg[0] + FSCALE) * hz) >> (FSHIFT + 1));
        callout_reset(&ebus_blink_ch, s, ebus_blink, NULL);
}
#endif