root/arch/sparc/kernel/prom_irqtrans.c
// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>

#include <asm/oplib.h>
#include <asm/prom.h>
#include <asm/irq.h>
#include <asm/upa.h>

#include "prom.h"

#ifdef CONFIG_PCI
/* PSYCHO interrupt mapping support. */
#define PSYCHO_IMAP_A_SLOT0     0x0c00UL
#define PSYCHO_IMAP_B_SLOT0     0x0c20UL
static unsigned long psycho_pcislot_imap_offset(unsigned long ino)
{
        unsigned int bus =  (ino & 0x10) >> 4;
        unsigned int slot = (ino & 0x0c) >> 2;

        if (bus == 0)
                return PSYCHO_IMAP_A_SLOT0 + (slot * 8);
        else
                return PSYCHO_IMAP_B_SLOT0 + (slot * 8);
}

#define PSYCHO_OBIO_IMAP_BASE   0x1000UL

#define PSYCHO_ONBOARD_IRQ_BASE         0x20
#define psycho_onboard_imap_offset(__ino) \
        (PSYCHO_OBIO_IMAP_BASE + (((__ino) & 0x1f) << 3))

#define PSYCHO_ICLR_A_SLOT0     0x1400UL
#define PSYCHO_ICLR_SCSI        0x1800UL

#define psycho_iclr_offset(ino)                                       \
        ((ino & 0x20) ? (PSYCHO_ICLR_SCSI + (((ino) & 0x1f) << 3)) :  \
                        (PSYCHO_ICLR_A_SLOT0 + (((ino) & 0x1f)<<3)))

static unsigned int psycho_irq_build(struct device_node *dp,
                                     unsigned int ino,
                                     void *_data)
{
        unsigned long controller_regs = (unsigned long) _data;
        unsigned long imap, iclr;
        unsigned long imap_off, iclr_off;
        int inofixup = 0;

        ino &= 0x3f;
        if (ino < PSYCHO_ONBOARD_IRQ_BASE) {
                /* PCI slot */
                imap_off = psycho_pcislot_imap_offset(ino);
        } else {
                /* Onboard device */
                imap_off = psycho_onboard_imap_offset(ino);
        }

        /* Now build the IRQ bucket. */
        imap = controller_regs + imap_off;

        iclr_off = psycho_iclr_offset(ino);
        iclr = controller_regs + iclr_off;

        if ((ino & 0x20) == 0)
                inofixup = ino & 0x03;

        return build_irq(inofixup, iclr, imap);
}

static void __init psycho_irq_trans_init(struct device_node *dp)
{
        const struct linux_prom64_registers *regs;

        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = psycho_irq_build;

        regs = of_get_property(dp, "reg", NULL);
        dp->irq_trans->data = (void *) regs[2].phys_addr;
}

#define sabre_read(__reg) \
({      u64 __ret; \
        __asm__ __volatile__("ldxa [%1] %2, %0" \
                             : "=r" (__ret) \
                             : "r" (__reg), "i" (ASI_PHYS_BYPASS_EC_E) \
                             : "memory"); \
        __ret; \
})

struct sabre_irq_data {
        unsigned long controller_regs;
        unsigned int pci_first_busno;
};
#define SABRE_CONFIGSPACE       0x001000000UL
#define SABRE_WRSYNC            0x1c20UL

#define SABRE_CONFIG_BASE(CONFIG_SPACE) \
        (CONFIG_SPACE | (1UL << 24))
#define SABRE_CONFIG_ENCODE(BUS, DEVFN, REG)    \
        (((unsigned long)(BUS)   << 16) |       \
         ((unsigned long)(DEVFN) << 8)  |       \
         ((unsigned long)(REG)))

/* When a device lives behind a bridge deeper in the PCI bus topology
 * than APB, a special sequence must run to make sure all pending DMA
 * transfers at the time of IRQ delivery are visible in the coherency
 * domain by the cpu.  This sequence is to perform a read on the far
 * side of the non-APB bridge, then perform a read of Sabre's DMA
 * write-sync register.
 */
static void sabre_wsync_handler(unsigned int ino, void *_arg1, void *_arg2)
{
        unsigned int phys_hi = (unsigned int) (unsigned long) _arg1;
        struct sabre_irq_data *irq_data = _arg2;
        unsigned long controller_regs = irq_data->controller_regs;
        unsigned long sync_reg = controller_regs + SABRE_WRSYNC;
        unsigned long config_space = controller_regs + SABRE_CONFIGSPACE;
        unsigned int bus, devfn;
        u16 _unused;

        config_space = SABRE_CONFIG_BASE(config_space);

        bus = (phys_hi >> 16) & 0xff;
        devfn = (phys_hi >> 8) & 0xff;

        config_space |= SABRE_CONFIG_ENCODE(bus, devfn, 0x00);

        __asm__ __volatile__("membar #Sync\n\t"
                             "lduha [%1] %2, %0\n\t"
                             "membar #Sync"
                             : "=r" (_unused)
                             : "r" ((u16 *) config_space),
                               "i" (ASI_PHYS_BYPASS_EC_E_L)
                             : "memory");

        sabre_read(sync_reg);
}

#define SABRE_IMAP_A_SLOT0      0x0c00UL
#define SABRE_IMAP_B_SLOT0      0x0c20UL
#define SABRE_ICLR_A_SLOT0      0x1400UL
#define SABRE_ICLR_B_SLOT0      0x1480UL
#define SABRE_ICLR_SCSI         0x1800UL
#define SABRE_ICLR_ETH          0x1808UL
#define SABRE_ICLR_BPP          0x1810UL
#define SABRE_ICLR_AU_REC       0x1818UL
#define SABRE_ICLR_AU_PLAY      0x1820UL
#define SABRE_ICLR_PFAIL        0x1828UL
#define SABRE_ICLR_KMS          0x1830UL
#define SABRE_ICLR_FLPY         0x1838UL
#define SABRE_ICLR_SHW          0x1840UL
#define SABRE_ICLR_KBD          0x1848UL
#define SABRE_ICLR_MS           0x1850UL
#define SABRE_ICLR_SER          0x1858UL
#define SABRE_ICLR_UE           0x1870UL
#define SABRE_ICLR_CE           0x1878UL
#define SABRE_ICLR_PCIERR       0x1880UL

static unsigned long sabre_pcislot_imap_offset(unsigned long ino)
{
        unsigned int bus =  (ino & 0x10) >> 4;
        unsigned int slot = (ino & 0x0c) >> 2;

        if (bus == 0)
                return SABRE_IMAP_A_SLOT0 + (slot * 8);
        else
                return SABRE_IMAP_B_SLOT0 + (slot * 8);
}

#define SABRE_OBIO_IMAP_BASE    0x1000UL
#define SABRE_ONBOARD_IRQ_BASE  0x20
#define sabre_onboard_imap_offset(__ino) \
        (SABRE_OBIO_IMAP_BASE + (((__ino) & 0x1f) << 3))

#define sabre_iclr_offset(ino)                                        \
        ((ino & 0x20) ? (SABRE_ICLR_SCSI + (((ino) & 0x1f) << 3)) :  \
                        (SABRE_ICLR_A_SLOT0 + (((ino) & 0x1f)<<3)))

static int sabre_device_needs_wsync(struct device_node *dp)
{
        struct device_node *parent = dp->parent;
        const char *parent_model, *parent_compat;

        /* This traversal up towards the root is meant to
         * handle two cases:
         *
         * 1) non-PCI bus sitting under PCI, such as 'ebus'
         * 2) the PCI controller interrupts themselves, which
         *    will use the sabre_irq_build but do not need
         *    the DMA synchronization handling
         */
        while (parent) {
                if (of_node_is_type(parent, "pci"))
                        break;
                parent = parent->parent;
        }

        if (!parent)
                return 0;

        parent_model = of_get_property(parent,
                                       "model", NULL);
        if (parent_model &&
            (!strcmp(parent_model, "SUNW,sabre") ||
             !strcmp(parent_model, "SUNW,simba")))
                return 0;

        parent_compat = of_get_property(parent,
                                        "compatible", NULL);
        if (parent_compat &&
            (!strcmp(parent_compat, "pci108e,a000") ||
             !strcmp(parent_compat, "pci108e,a001")))
                return 0;

        return 1;
}

static unsigned int sabre_irq_build(struct device_node *dp,
                                    unsigned int ino,
                                    void *_data)
{
        struct sabre_irq_data *irq_data = _data;
        unsigned long controller_regs = irq_data->controller_regs;
        const struct linux_prom_pci_registers *regs;
        unsigned long imap, iclr;
        unsigned long imap_off, iclr_off;
        int inofixup = 0;
        int irq;

        ino &= 0x3f;
        if (ino < SABRE_ONBOARD_IRQ_BASE) {
                /* PCI slot */
                imap_off = sabre_pcislot_imap_offset(ino);
        } else {
                /* onboard device */
                imap_off = sabre_onboard_imap_offset(ino);
        }

        /* Now build the IRQ bucket. */
        imap = controller_regs + imap_off;

        iclr_off = sabre_iclr_offset(ino);
        iclr = controller_regs + iclr_off;

        if ((ino & 0x20) == 0)
                inofixup = ino & 0x03;

        irq = build_irq(inofixup, iclr, imap);

        /* If the parent device is a PCI<->PCI bridge other than
         * APB, we have to install a pre-handler to ensure that
         * all pending DMA is drained before the interrupt handler
         * is run.
         */
        regs = of_get_property(dp, "reg", NULL);
        if (regs && sabre_device_needs_wsync(dp)) {
                irq_install_pre_handler(irq,
                                        sabre_wsync_handler,
                                        (void *) (long) regs->phys_hi,
                                        (void *) irq_data);
        }

        return irq;
}

static void __init sabre_irq_trans_init(struct device_node *dp)
{
        const struct linux_prom64_registers *regs;
        struct sabre_irq_data *irq_data;
        const u32 *busrange;

        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = sabre_irq_build;

        irq_data = prom_early_alloc(sizeof(struct sabre_irq_data));

        regs = of_get_property(dp, "reg", NULL);
        irq_data->controller_regs = regs[0].phys_addr;

        busrange = of_get_property(dp, "bus-range", NULL);
        irq_data->pci_first_busno = busrange[0];

        dp->irq_trans->data = irq_data;
}

/* SCHIZO interrupt mapping support.  Unlike Psycho, for this controller the
 * imap/iclr registers are per-PBM.
 */
#define SCHIZO_IMAP_BASE        0x1000UL
#define SCHIZO_ICLR_BASE        0x1400UL

static unsigned long schizo_imap_offset(unsigned long ino)
{
        return SCHIZO_IMAP_BASE + (ino * 8UL);
}

static unsigned long schizo_iclr_offset(unsigned long ino)
{
        return SCHIZO_ICLR_BASE + (ino * 8UL);
}

static unsigned long schizo_ino_to_iclr(unsigned long pbm_regs,
                                        unsigned int ino)
{

        return pbm_regs + schizo_iclr_offset(ino);
}

static unsigned long schizo_ino_to_imap(unsigned long pbm_regs,
                                        unsigned int ino)
{
        return pbm_regs + schizo_imap_offset(ino);
}

#define schizo_read(__reg) \
({      u64 __ret; \
        __asm__ __volatile__("ldxa [%1] %2, %0" \
                             : "=r" (__ret) \
                             : "r" (__reg), "i" (ASI_PHYS_BYPASS_EC_E) \
                             : "memory"); \
        __ret; \
})
#define schizo_write(__reg, __val) \
        __asm__ __volatile__("stxa %0, [%1] %2" \
                             : /* no outputs */ \
                             : "r" (__val), "r" (__reg), \
                               "i" (ASI_PHYS_BYPASS_EC_E) \
                             : "memory")

static void tomatillo_wsync_handler(unsigned int ino, void *_arg1, void *_arg2)
{
        unsigned long sync_reg = (unsigned long) _arg2;
        u64 mask = 1UL << (ino & IMAP_INO);
        u64 val;
        int limit;

        schizo_write(sync_reg, mask);

        limit = 100000;
        val = 0;
        while (--limit) {
                val = schizo_read(sync_reg);
                if (!(val & mask))
                        break;
        }
        if (limit <= 0) {
                printk("tomatillo_wsync_handler: DMA won't sync [%llx:%llx]\n",
                       val, mask);
        }

        if (_arg1) {
                static unsigned char cacheline[64]
                        __attribute__ ((aligned (64)));

                __asm__ __volatile__("rd %%fprs, %0\n\t"
                                     "or %0, %4, %1\n\t"
                                     "wr %1, 0x0, %%fprs\n\t"
                                     "stda %%f0, [%5] %6\n\t"
                                     "wr %0, 0x0, %%fprs\n\t"
                                     "membar #Sync"
                                     : "=&r" (mask), "=&r" (val)
                                     : "0" (mask), "1" (val),
                                     "i" (FPRS_FEF), "r" (&cacheline[0]),
                                     "i" (ASI_BLK_COMMIT_P));
        }
}

struct schizo_irq_data {
        unsigned long pbm_regs;
        unsigned long sync_reg;
        u32 portid;
        int chip_version;
};

static unsigned int schizo_irq_build(struct device_node *dp,
                                     unsigned int ino,
                                     void *_data)
{
        struct schizo_irq_data *irq_data = _data;
        unsigned long pbm_regs = irq_data->pbm_regs;
        unsigned long imap, iclr;
        int ign_fixup;
        int irq;
        int is_tomatillo;

        ino &= 0x3f;

        /* Now build the IRQ bucket. */
        imap = schizo_ino_to_imap(pbm_regs, ino);
        iclr = schizo_ino_to_iclr(pbm_regs, ino);

        /* On Schizo, no inofixup occurs.  This is because each
         * INO has its own IMAP register.  On Psycho and Sabre
         * there is only one IMAP register for each PCI slot even
         * though four different INOs can be generated by each
         * PCI slot.
         *
         * But, for JBUS variants (essentially, Tomatillo), we have
         * to fixup the lowest bit of the interrupt group number.
         */
        ign_fixup = 0;

        is_tomatillo = (irq_data->sync_reg != 0UL);

        if (is_tomatillo) {
                if (irq_data->portid & 1)
                        ign_fixup = (1 << 6);
        }

        irq = build_irq(ign_fixup, iclr, imap);

        if (is_tomatillo) {
                irq_install_pre_handler(irq,
                                        tomatillo_wsync_handler,
                                        ((irq_data->chip_version <= 4) ?
                                         (void *) 1 : (void *) 0),
                                        (void *) irq_data->sync_reg);
        }

        return irq;
}

static void __init __schizo_irq_trans_init(struct device_node *dp,
                                           int is_tomatillo)
{
        const struct linux_prom64_registers *regs;
        struct schizo_irq_data *irq_data;

        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = schizo_irq_build;

        irq_data = prom_early_alloc(sizeof(struct schizo_irq_data));

        regs = of_get_property(dp, "reg", NULL);
        dp->irq_trans->data = irq_data;

        irq_data->pbm_regs = regs[0].phys_addr;
        if (is_tomatillo)
                irq_data->sync_reg = regs[3].phys_addr + 0x1a18UL;
        else
                irq_data->sync_reg = 0UL;
        irq_data->portid = of_getintprop_default(dp, "portid", 0);
        irq_data->chip_version = of_getintprop_default(dp, "version#", 0);
}

static void __init schizo_irq_trans_init(struct device_node *dp)
{
        __schizo_irq_trans_init(dp, 0);
}

static void __init tomatillo_irq_trans_init(struct device_node *dp)
{
        __schizo_irq_trans_init(dp, 1);
}

static unsigned int pci_sun4v_irq_build(struct device_node *dp,
                                        unsigned int devino,
                                        void *_data)
{
        u32 devhandle = (u32) (unsigned long) _data;

        return sun4v_build_irq(devhandle, devino);
}

static void __init pci_sun4v_irq_trans_init(struct device_node *dp)
{
        const struct linux_prom64_registers *regs;

        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = pci_sun4v_irq_build;

        regs = of_get_property(dp, "reg", NULL);
        dp->irq_trans->data = (void *) (unsigned long)
                ((regs->phys_addr >> 32UL) & 0x0fffffff);
}

struct fire_irq_data {
        unsigned long pbm_regs;
        u32 portid;
};

#define FIRE_IMAP_BASE  0x001000
#define FIRE_ICLR_BASE  0x001400

static unsigned long fire_imap_offset(unsigned long ino)
{
        return FIRE_IMAP_BASE + (ino * 8UL);
}

static unsigned long fire_iclr_offset(unsigned long ino)
{
        return FIRE_ICLR_BASE + (ino * 8UL);
}

static unsigned long fire_ino_to_iclr(unsigned long pbm_regs,
                                            unsigned int ino)
{
        return pbm_regs + fire_iclr_offset(ino);
}

static unsigned long fire_ino_to_imap(unsigned long pbm_regs,
                                            unsigned int ino)
{
        return pbm_regs + fire_imap_offset(ino);
}

static unsigned int fire_irq_build(struct device_node *dp,
                                         unsigned int ino,
                                         void *_data)
{
        struct fire_irq_data *irq_data = _data;
        unsigned long pbm_regs = irq_data->pbm_regs;
        unsigned long imap, iclr;
        unsigned long int_ctrlr;

        ino &= 0x3f;

        /* Now build the IRQ bucket. */
        imap = fire_ino_to_imap(pbm_regs, ino);
        iclr = fire_ino_to_iclr(pbm_regs, ino);

        /* Set the interrupt controller number.  */
        int_ctrlr = 1 << 6;
        upa_writeq(int_ctrlr, imap);

        /* The interrupt map registers do not have an INO field
         * like other chips do.  They return zero in the INO
         * field, and the interrupt controller number is controlled
         * in bits 6 to 9.  So in order for build_irq() to get
         * the INO right we pass it in as part of the fixup
         * which will get added to the map register zero value
         * read by build_irq().
         */
        ino |= (irq_data->portid << 6);
        ino -= int_ctrlr;
        return build_irq(ino, iclr, imap);
}

static void __init fire_irq_trans_init(struct device_node *dp)
{
        const struct linux_prom64_registers *regs;
        struct fire_irq_data *irq_data;

        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = fire_irq_build;

        irq_data = prom_early_alloc(sizeof(struct fire_irq_data));

        regs = of_get_property(dp, "reg", NULL);
        dp->irq_trans->data = irq_data;

        irq_data->pbm_regs = regs[0].phys_addr;
        irq_data->portid = of_getintprop_default(dp, "portid", 0);
}
#endif /* CONFIG_PCI */

#ifdef CONFIG_SBUS
/* INO number to IMAP register offset for SYSIO external IRQ's.
 * This should conform to both Sunfire/Wildfire server and Fusion
 * desktop designs.
 */
#define SYSIO_IMAP_SLOT0        0x2c00UL
#define SYSIO_IMAP_SLOT1        0x2c08UL
#define SYSIO_IMAP_SLOT2        0x2c10UL
#define SYSIO_IMAP_SLOT3        0x2c18UL
#define SYSIO_IMAP_SCSI         0x3000UL
#define SYSIO_IMAP_ETH          0x3008UL
#define SYSIO_IMAP_BPP          0x3010UL
#define SYSIO_IMAP_AUDIO        0x3018UL
#define SYSIO_IMAP_PFAIL        0x3020UL
#define SYSIO_IMAP_KMS          0x3028UL
#define SYSIO_IMAP_FLPY         0x3030UL
#define SYSIO_IMAP_SHW          0x3038UL
#define SYSIO_IMAP_KBD          0x3040UL
#define SYSIO_IMAP_MS           0x3048UL
#define SYSIO_IMAP_SER          0x3050UL
#define SYSIO_IMAP_TIM0         0x3060UL
#define SYSIO_IMAP_TIM1         0x3068UL
#define SYSIO_IMAP_UE           0x3070UL
#define SYSIO_IMAP_CE           0x3078UL
#define SYSIO_IMAP_SBERR        0x3080UL
#define SYSIO_IMAP_PMGMT        0x3088UL
#define SYSIO_IMAP_GFX          0x3090UL
#define SYSIO_IMAP_EUPA         0x3098UL

#define bogon     ((unsigned long) -1)
static unsigned long sysio_irq_offsets[] = {
        /* SBUS Slot 0 --> 3, level 1 --> 7 */
        SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0,
        SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0, SYSIO_IMAP_SLOT0,
        SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1,
        SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1, SYSIO_IMAP_SLOT1,
        SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2,
        SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2, SYSIO_IMAP_SLOT2,
        SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3,
        SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3, SYSIO_IMAP_SLOT3,

        /* Onboard devices (not relevant/used on SunFire). */
        SYSIO_IMAP_SCSI,
        SYSIO_IMAP_ETH,
        SYSIO_IMAP_BPP,
        bogon,
        SYSIO_IMAP_AUDIO,
        SYSIO_IMAP_PFAIL,
        bogon,
        bogon,
        SYSIO_IMAP_KMS,
        SYSIO_IMAP_FLPY,
        SYSIO_IMAP_SHW,
        SYSIO_IMAP_KBD,
        SYSIO_IMAP_MS,
        SYSIO_IMAP_SER,
        bogon,
        bogon,
        SYSIO_IMAP_TIM0,
        SYSIO_IMAP_TIM1,
        bogon,
        bogon,
        SYSIO_IMAP_UE,
        SYSIO_IMAP_CE,
        SYSIO_IMAP_SBERR,
        SYSIO_IMAP_PMGMT,
        SYSIO_IMAP_GFX,
        SYSIO_IMAP_EUPA,
};

#undef bogon

#define NUM_SYSIO_OFFSETS ARRAY_SIZE(sysio_irq_offsets)

/* Convert Interrupt Mapping register pointer to associated
 * Interrupt Clear register pointer, SYSIO specific version.
 */
#define SYSIO_ICLR_UNUSED0      0x3400UL
#define SYSIO_ICLR_SLOT0        0x3408UL
#define SYSIO_ICLR_SLOT1        0x3448UL
#define SYSIO_ICLR_SLOT2        0x3488UL
#define SYSIO_ICLR_SLOT3        0x34c8UL
static unsigned long sysio_imap_to_iclr(unsigned long imap)
{
        unsigned long diff = SYSIO_ICLR_UNUSED0 - SYSIO_IMAP_SLOT0;
        return imap + diff;
}

static unsigned int sbus_of_build_irq(struct device_node *dp,
                                      unsigned int ino,
                                      void *_data)
{
        unsigned long reg_base = (unsigned long) _data;
        const struct linux_prom_registers *regs;
        unsigned long imap, iclr;
        int sbus_slot = 0;
        int sbus_level = 0;

        ino &= 0x3f;

        regs = of_get_property(dp, "reg", NULL);
        if (regs)
                sbus_slot = regs->which_io;

        if (ino < 0x20)
                ino += (sbus_slot * 8);

        imap = sysio_irq_offsets[ino];
        if (imap == ((unsigned long)-1)) {
                prom_printf("get_irq_translations: Bad SYSIO INO[%x]\n",
                            ino);
                prom_halt();
        }
        imap += reg_base;

        /* SYSIO inconsistency.  For external SLOTS, we have to select
         * the right ICLR register based upon the lower SBUS irq level
         * bits.
         */
        if (ino >= 0x20) {
                iclr = sysio_imap_to_iclr(imap);
        } else {
                sbus_level = ino & 0x7;

                switch(sbus_slot) {
                case 0:
                        iclr = reg_base + SYSIO_ICLR_SLOT0;
                        break;
                case 1:
                        iclr = reg_base + SYSIO_ICLR_SLOT1;
                        break;
                case 2:
                        iclr = reg_base + SYSIO_ICLR_SLOT2;
                        break;
                default:
                case 3:
                        iclr = reg_base + SYSIO_ICLR_SLOT3;
                        break;
                }

                iclr += ((unsigned long)sbus_level - 1UL) * 8UL;
        }
        return build_irq(sbus_level, iclr, imap);
}

static void __init sbus_irq_trans_init(struct device_node *dp)
{
        const struct linux_prom64_registers *regs;

        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = sbus_of_build_irq;

        regs = of_get_property(dp, "reg", NULL);
        dp->irq_trans->data = (void *) (unsigned long) regs->phys_addr;
}
#endif /* CONFIG_SBUS */


static unsigned int central_build_irq(struct device_node *dp,
                                      unsigned int ino,
                                      void *_data)
{
        struct device_node *central_dp = _data;
        struct platform_device *central_op = of_find_device_by_node(central_dp);
        struct resource *res;
        unsigned long imap, iclr;
        u32 tmp;

        if (of_node_name_eq(dp, "eeprom")) {
                res = &central_op->resource[5];
        } else if (of_node_name_eq(dp, "zs")) {
                res = &central_op->resource[4];
        } else if (of_node_name_eq(dp, "clock-board")) {
                res = &central_op->resource[3];
        } else {
                return ino;
        }

        imap = res->start + 0x00UL;
        iclr = res->start + 0x10UL;

        /* Set the INO state to idle, and disable.  */
        upa_writel(0, iclr);
        upa_readl(iclr);

        tmp = upa_readl(imap);
        tmp &= ~0x80000000;
        upa_writel(tmp, imap);

        return build_irq(0, iclr, imap);
}

static void __init central_irq_trans_init(struct device_node *dp)
{
        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = central_build_irq;

        dp->irq_trans->data = dp;
}

struct irq_trans {
        const char *name;
        void (*init)(struct device_node *);
};

#ifdef CONFIG_PCI
static struct irq_trans __initdata pci_irq_trans_table[] = {
        { "SUNW,sabre", sabre_irq_trans_init },
        { "pci108e,a000", sabre_irq_trans_init },
        { "pci108e,a001", sabre_irq_trans_init },
        { "SUNW,psycho", psycho_irq_trans_init },
        { "pci108e,8000", psycho_irq_trans_init },
        { "SUNW,schizo", schizo_irq_trans_init },
        { "pci108e,8001", schizo_irq_trans_init },
        { "SUNW,schizo+", schizo_irq_trans_init },
        { "pci108e,8002", schizo_irq_trans_init },
        { "SUNW,tomatillo", tomatillo_irq_trans_init },
        { "pci108e,a801", tomatillo_irq_trans_init },
        { "SUNW,sun4v-pci", pci_sun4v_irq_trans_init },
        { "pciex108e,80f0", fire_irq_trans_init },
};
#endif

static unsigned int sun4v_vdev_irq_build(struct device_node *dp,
                                         unsigned int devino,
                                         void *_data)
{
        u32 devhandle = (u32) (unsigned long) _data;

        return sun4v_build_irq(devhandle, devino);
}

static void __init sun4v_vdev_irq_trans_init(struct device_node *dp)
{
        const struct linux_prom64_registers *regs;

        dp->irq_trans = prom_early_alloc(sizeof(struct of_irq_controller));
        dp->irq_trans->irq_build = sun4v_vdev_irq_build;

        regs = of_get_property(dp, "reg", NULL);
        dp->irq_trans->data = (void *) (unsigned long)
                ((regs->phys_addr >> 32UL) & 0x0fffffff);
}

void __init irq_trans_init(struct device_node *dp)
{
#ifdef CONFIG_PCI
        const char *model;
        int i;
#endif

#ifdef CONFIG_PCI
        model = of_get_property(dp, "model", NULL);
        if (!model)
                model = of_get_property(dp, "compatible", NULL);
        if (model) {
                for (i = 0; i < ARRAY_SIZE(pci_irq_trans_table); i++) {
                        struct irq_trans *t = &pci_irq_trans_table[i];

                        if (!strcmp(model, t->name)) {
                                t->init(dp);
                                return;
                        }
                }
        }
#endif
#ifdef CONFIG_SBUS
        if (of_node_name_eq(dp, "sbus") ||
            of_node_name_eq(dp, "sbi")) {
                sbus_irq_trans_init(dp);
                return;
        }
#endif
        if (of_node_name_eq(dp, "fhc") &&
            of_node_name_eq(dp->parent, "central")) {
                central_irq_trans_init(dp);
                return;
        }
        if (of_node_name_eq(dp, "virtual-devices") ||
            of_node_name_eq(dp, "niu")) {
                sun4v_vdev_irq_trans_init(dp);
                return;
        }
}