/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * SNI specific PCI support for RM200/RM300.
 *
 * Copyright (C) 1997 - 2000, 2003, 04 Ralf Baechle (ralf@linux-mips.org)
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/pci.h>

#include <asm/mipsregs.h>
#include <asm/sni.h>

#include <irq.h>

/*
 * PCIMT Shortcuts ...
 */
#define SCSI    PCIMT_IRQ_SCSI
#define ETH     PCIMT_IRQ_ETHERNET
#define INTA    PCIMT_IRQ_INTA
#define INTB    PCIMT_IRQ_INTB
#define INTC    PCIMT_IRQ_INTC
#define INTD    PCIMT_IRQ_INTD

/*
 * Device 0: PCI EISA Bridge    (directly routed)
 * Device 1: NCR53c810 SCSI     (directly routed)
 * Device 2: PCnet32 Ethernet   (directly routed)
 * Device 3: VGA                (routed to INTB)
 * Device 4: Unused
 * Device 5: Slot 2
 * Device 6: Slot 3
 * Device 7: Slot 4
 *
 * Documentation says the VGA is device 5 and device 3 is unused but that
 * seem to be a documentation error.  At least on my RM200C the Cirrus
 * Logic CL-GD5434 VGA is device 3.
 */
static char irq_tab_rm200[8][5] = {
        /*       INTA  INTB  INTC  INTD */
        {     0,    0,    0,    0,    0 },      /* EISA bridge */
        {  SCSI, SCSI, SCSI, SCSI, SCSI },      /* SCSI */
        {   ETH,  ETH,  ETH,  ETH,  ETH },      /* Ethernet */
        {  INTB, INTB, INTB, INTB, INTB },      /* VGA */
        {     0,    0,    0,    0,    0 },      /* Unused */
        {     0, INTB, INTC, INTD, INTA },      /* Slot 2 */
        {     0, INTC, INTD, INTA, INTB },      /* Slot 3 */
        {     0, INTD, INTA, INTB, INTC },      /* Slot 4 */
};

/*
 * In Revision D of the RM300 Device 2 has become a normal purpose Slot 1
 *
 * The VGA card is optional for RM300 systems.
 */
static char irq_tab_rm300d[8][5] = {
        /*       INTA  INTB  INTC  INTD */
        {     0,    0,    0,    0,    0 },      /* EISA bridge */
        {  SCSI, SCSI, SCSI, SCSI, SCSI },      /* SCSI */
        {     0, INTC, INTD, INTA, INTB },      /* Slot 1 */
        {  INTB, INTB, INTB, INTB, INTB },      /* VGA */
        {     0,    0,    0,    0,    0 },      /* Unused */
        {     0, INTB, INTC, INTD, INTA },      /* Slot 2 */
        {     0, INTC, INTD, INTA, INTB },      /* Slot 3 */
        {     0, INTD, INTA, INTB, INTC },      /* Slot 4 */
};

static char irq_tab_rm300e[5][5] = {
        /*       INTA  INTB  INTC  INTD */
        {     0,    0,    0,    0,    0 },      /* HOST bridge */
        {  SCSI, SCSI, SCSI, SCSI, SCSI },      /* SCSI */
        {     0, INTC, INTD, INTA, INTB },      /* Bridge/i960 */
        {     0, INTD, INTA, INTB, INTC },      /* Slot 1 */
        {     0, INTA, INTB, INTC, INTD },      /* Slot 2 */
};
#undef SCSI
#undef ETH
#undef INTA
#undef INTB
#undef INTC
#undef INTD


/*
 * PCIT Shortcuts ...
 */
#define SCSI0   PCIT_IRQ_SCSI0
#define SCSI1   PCIT_IRQ_SCSI1
#define ETH     PCIT_IRQ_ETHERNET
#define INTA    PCIT_IRQ_INTA
#define INTB    PCIT_IRQ_INTB
#define INTC    PCIT_IRQ_INTC
#define INTD    PCIT_IRQ_INTD

static char irq_tab_pcit[13][5] = {
        /*       INTA  INTB  INTC  INTD */
        {     0,     0,     0,     0,     0 },  /* HOST bridge */
        { SCSI0, SCSI0, SCSI0, SCSI0, SCSI0 },  /* SCSI */
        { SCSI1, SCSI1, SCSI1, SCSI1, SCSI1 },  /* SCSI */
        {   ETH,   ETH,   ETH,   ETH,   ETH },  /* Ethernet */
        {     0,  INTA,  INTB,  INTC,  INTD },  /* PCI-PCI bridge */
        {     0,     0,     0,     0,     0 },  /* Unused */
        {     0,     0,     0,     0,     0 },  /* Unused */
        {     0,     0,     0,     0,     0 },  /* Unused */
        {     0,  INTA,  INTB,  INTC,  INTD },  /* Slot 1 */
        {     0,  INTB,  INTC,  INTD,  INTA },  /* Slot 2 */
        {     0,  INTC,  INTD,  INTA,  INTB },  /* Slot 3 */
        {     0,  INTD,  INTA,  INTB,  INTC },  /* Slot 4 */
        {     0,  INTA,  INTB,  INTC,  INTD },  /* Slot 5 */
};

static char irq_tab_pcit_cplus[13][5] = {
        /*       INTA  INTB  INTC  INTD */
        {     0,     0,     0,     0,     0 },  /* HOST bridge */
        {     0,  INTB,  INTC,  INTD,  INTA },  /* PCI Slot 9 */
        {     0,     0,     0,     0,     0 },  /* PCI-EISA */
        {     0,     0,     0,     0,     0 },  /* Unused */
        {     0,  INTA,  INTB,  INTC,  INTD },  /* PCI-PCI bridge */
        {     0,  INTB,  INTC,  INTD,  INTA },  /* fixup */
};

static inline int is_rm300_revd(void)
{
        unsigned char csmsr = *(volatile unsigned char *)PCIMT_CSMSR;

        return (csmsr & 0xa0) == 0x20;
}

int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
        switch (sni_brd_type) {
        case SNI_BRD_PCI_TOWER_CPLUS:
                if (slot == 4) {
                        /*
                         * SNI messed up interrupt wiring for onboard
                         * PCI bus 1; we need to fix this up here
                         */
                        while (dev && dev->bus->number != 1)
                                dev = dev->bus->self;
                        if (dev && dev->devfn >= PCI_DEVFN(4, 0))
                                slot = 5;
                }
                return irq_tab_pcit_cplus[slot][pin];
        case SNI_BRD_PCI_TOWER:
                return irq_tab_pcit[slot][pin];

        case SNI_BRD_PCI_MTOWER:
                if (is_rm300_revd())
                        return irq_tab_rm300d[slot][pin];
                fallthrough;
        case SNI_BRD_PCI_DESKTOP:
                return irq_tab_rm200[slot][pin];

        case SNI_BRD_PCI_MTOWER_CPLUS:
                return irq_tab_rm300e[slot][pin];
        }

        return 0;
}

/* Do platform specific device initialization at pci_enable_device() time */
int pcibios_plat_dev_init(struct pci_dev *dev)
{
        return 0;
}