/*
 *  SGI Visual Workstation support and quirks, unmaintained.
 *
 *  Split out from setup.c by davej@suse.de
 *
 *      Copyright (C) 1999 Bent Hagemark, Ingo Molnar
 *
 *  SGI Visual Workstation interrupt controller
 *
 *  The Cobalt system ASIC in the Visual Workstation contains a "Cobalt" APIC
 *  which serves as the main interrupt controller in the system.  Non-legacy
 *  hardware in the system uses this controller directly.  Legacy devices
 *  are connected to the PIIX4 which in turn has its 8259(s) connected to
 *  a of the Cobalt APIC entry.
 *
 *  09/02/2000 - Updated for 2.4 by jbarnes@sgi.com
 *
 *  25/11/2002 - Updated for 2.5 by Andrey Panin <pazke@orbita1.ru>
 */
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/smp.h>

#include <asm/visws/cobalt.h>
#include <asm/visws/piix4.h>
#include <asm/io_apic.h>
#include <asm/fixmap.h>
#include <asm/reboot.h>
#include <asm/setup.h>
#include <asm/apic.h>
#include <asm/e820.h>
#include <asm/time.h>
#include <asm/io.h>

#include <linux/kernel_stat.h>

#include <asm/i8259.h>
#include <asm/irq_vectors.h>
#include <asm/visws/lithium.h>

#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>

extern int no_broadcast;

char visws_board_type   = -1;
char visws_board_rev    = -1;

static void __init visws_time_init(void)
{
        printk(KERN_INFO "Starting Cobalt Timer system clock\n");

        /* Set the countdown value */
        co_cpu_write(CO_CPU_TIMEVAL, CO_TIME_HZ/HZ);

        /* Start the timer */
        co_cpu_write(CO_CPU_CTRL, co_cpu_read(CO_CPU_CTRL) | CO_CTRL_TIMERUN);

        /* Enable (unmask) the timer interrupt */
        co_cpu_write(CO_CPU_CTRL, co_cpu_read(CO_CPU_CTRL) & ~CO_CTRL_TIMEMASK);

        setup_default_timer_irq();
}

/* Replaces the default init_ISA_irqs in the generic setup */
static void __init visws_pre_intr_init(void);

/* Quirk for machine specific memory setup. */

#define MB (1024 * 1024)

unsigned long sgivwfb_mem_phys;
unsigned long sgivwfb_mem_size;
EXPORT_SYMBOL(sgivwfb_mem_phys);
EXPORT_SYMBOL(sgivwfb_mem_size);

long long mem_size __initdata = 0;

static char * __init visws_memory_setup(void)
{
        long long gfx_mem_size = 8 * MB;

        mem_size = boot_params.alt_mem_k;

        if (!mem_size) {
                printk(KERN_WARNING "Bootloader didn't set memory size, upgrade it !\n");
                mem_size = 128 * MB;
        }

        /*
         * this hardcodes the graphics memory to 8 MB
         * it really should be sized dynamically (or at least
         * set as a boot param)
         */
        if (!sgivwfb_mem_size) {
                printk(KERN_WARNING "Defaulting to 8 MB framebuffer size\n");
                sgivwfb_mem_size = 8 * MB;
        }

        /*
         * Trim to nearest MB
         */
        sgivwfb_mem_size &= ~((1 << 20) - 1);
        sgivwfb_mem_phys = mem_size - gfx_mem_size;

        e820_add_region(0, LOWMEMSIZE(), E820_RAM);
        e820_add_region(HIGH_MEMORY, mem_size - sgivwfb_mem_size - HIGH_MEMORY, E820_RAM);
        e820_add_region(sgivwfb_mem_phys, sgivwfb_mem_size, E820_RESERVED);

        return "PROM";
}

static void visws_machine_emergency_restart(void)
{
        /*
         * Visual Workstations restart after this
         * register is poked on the PIIX4
         */
        outb(PIIX4_RESET_VAL, PIIX4_RESET_PORT);
}

static void visws_machine_power_off(void)
{
        unsigned short pm_status;
/*      extern unsigned int pci_bus0; */

        while ((pm_status = inw(PMSTS_PORT)) & 0x100)
                outw(pm_status, PMSTS_PORT);

        outw(PM_SUSPEND_ENABLE, PMCNTRL_PORT);

        mdelay(10);

#define PCI_CONF1_ADDRESS(bus, devfn, reg) \
        (0x80000000 | (bus << 16) | (devfn << 8) | (reg & ~3))

/*      outl(PCI_CONF1_ADDRESS(pci_bus0, SPECIAL_DEV, SPECIAL_REG), 0xCF8); */
        outl(PIIX_SPECIAL_STOP, 0xCFC);
}

static void __init visws_get_smp_config(unsigned int early)
{
}

/*
 * The Visual Workstation is Intel MP compliant in the hardware
 * sense, but it doesn't have a BIOS(-configuration table).
 * No problem for Linux.
 */

static void __init MP_processor_info(struct mpc_cpu *m)
{
        int ver, logical_apicid;
        physid_mask_t apic_cpus;

        if (!(m->cpuflag & CPU_ENABLED))
                return;

        logical_apicid = m->apicid;
        printk(KERN_INFO "%sCPU #%d %u:%u APIC version %d\n",
               m->cpuflag & CPU_BOOTPROCESSOR ? "Bootup " : "",
               m->apicid, (m->cpufeature & CPU_FAMILY_MASK) >> 8,
               (m->cpufeature & CPU_MODEL_MASK) >> 4, m->apicver);

        if (m->cpuflag & CPU_BOOTPROCESSOR)
                boot_cpu_physical_apicid = m->apicid;

        ver = m->apicver;
        if ((ver >= 0x14 && m->apicid >= 0xff) || m->apicid >= 0xf) {
                printk(KERN_ERR "Processor #%d INVALID. (Max ID: %d).\n",
                        m->apicid, MAX_LOCAL_APIC);
                return;
        }

        apic->apicid_to_cpu_present(m->apicid, &apic_cpus);
        physids_or(phys_cpu_present_map, phys_cpu_present_map, apic_cpus);
        /*
         * Validate version
         */
        if (ver == 0x0) {
                printk(KERN_ERR "BIOS bug, APIC version is 0 for CPU#%d! "
                        "fixing up to 0x10. (tell your hw vendor)\n",
                        m->apicid);
                ver = 0x10;
        }
        apic_version[m->apicid] = ver;
}

static void __init visws_find_smp_config(void)
{
        struct mpc_cpu *mp = phys_to_virt(CO_CPU_TAB_PHYS);
        unsigned short ncpus = readw(phys_to_virt(CO_CPU_NUM_PHYS));

        if (ncpus > CO_CPU_MAX) {
                printk(KERN_WARNING "find_visws_smp: got cpu count of %d at %p\n",
                        ncpus, mp);

                ncpus = CO_CPU_MAX;
        }

        if (ncpus > setup_max_cpus)
                ncpus = setup_max_cpus;

#ifdef CONFIG_X86_LOCAL_APIC
        smp_found_config = 1;
#endif
        while (ncpus--)
                MP_processor_info(mp++);

        mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
}

static void visws_trap_init(void);

void __init visws_early_detect(void)
{
        int raw;

        visws_board_type = (char)(inb_p(PIIX_GPI_BD_REG) & PIIX_GPI_BD_REG)
                                                         >> PIIX_GPI_BD_SHIFT;

        if (visws_board_type < 0)
                return;

        /*
         * Override the default platform setup functions
         */
        x86_init.resources.memory_setup = visws_memory_setup;
        x86_init.mpparse.get_smp_config = visws_get_smp_config;
        x86_init.mpparse.find_smp_config = visws_find_smp_config;
        x86_init.irqs.pre_vector_init = visws_pre_intr_init;
        x86_init.irqs.trap_init = visws_trap_init;
        x86_init.timers.timer_init = visws_time_init;
        x86_init.pci.init = pci_visws_init;
        x86_init.pci.init_irq = x86_init_noop;

        /*
         * Install reboot quirks:
         */
        pm_power_off                    = visws_machine_power_off;
        machine_ops.emergency_restart   = visws_machine_emergency_restart;

        /*
         * Do not use broadcast IPIs:
         */
        no_broadcast = 0;

#ifdef CONFIG_X86_IO_APIC
        /*
         * Turn off IO-APIC detection and initialization:
         */
        skip_ioapic_setup               = 1;
#endif

        /*
         * Get Board rev.
         * First, we have to initialize the 307 part to allow us access
         * to the GPIO registers.  Let's map them at 0x0fc0 which is right
         * after the PIIX4 PM section.
         */
        outb_p(SIO_DEV_SEL, SIO_INDEX);
        outb_p(SIO_GP_DEV, SIO_DATA);   /* Talk to GPIO regs. */

        outb_p(SIO_DEV_MSB, SIO_INDEX);
        outb_p(SIO_GP_MSB, SIO_DATA);   /* MSB of GPIO base address */

        outb_p(SIO_DEV_LSB, SIO_INDEX);
        outb_p(SIO_GP_LSB, SIO_DATA);   /* LSB of GPIO base address */

        outb_p(SIO_DEV_ENB, SIO_INDEX);
        outb_p(1, SIO_DATA);            /* Enable GPIO registers. */

        /*
         * Now, we have to map the power management section to write
         * a bit which enables access to the GPIO registers.
         * What lunatic came up with this shit?
         */
        outb_p(SIO_DEV_SEL, SIO_INDEX);
        outb_p(SIO_PM_DEV, SIO_DATA);   /* Talk to GPIO regs. */

        outb_p(SIO_DEV_MSB, SIO_INDEX);
        outb_p(SIO_PM_MSB, SIO_DATA);   /* MSB of PM base address */

        outb_p(SIO_DEV_LSB, SIO_INDEX);
        outb_p(SIO_PM_LSB, SIO_DATA);   /* LSB of PM base address */

        outb_p(SIO_DEV_ENB, SIO_INDEX);
        outb_p(1, SIO_DATA);            /* Enable PM registers. */

        /*
         * Now, write the PM register which enables the GPIO registers.
         */
        outb_p(SIO_PM_FER2, SIO_PM_INDEX);
        outb_p(SIO_PM_GP_EN, SIO_PM_DATA);

        /*
         * Now, initialize the GPIO registers.
         * We want them all to be inputs which is the
         * power on default, so let's leave them alone.
         * So, let's just read the board rev!
         */
        raw = inb_p(SIO_GP_DATA1);
        raw &= 0x7f;    /* 7 bits of valid board revision ID. */

        if (visws_board_type == VISWS_320) {
                if (raw < 0x6) {
                        visws_board_rev = 4;
                } else if (raw < 0xc) {
                        visws_board_rev = 5;
                } else {
                        visws_board_rev = 6;
                }
        } else if (visws_board_type == VISWS_540) {
                        visws_board_rev = 2;
                } else {
                        visws_board_rev = raw;
                }

        printk(KERN_INFO "Silicon Graphics Visual Workstation %s (rev %d) detected\n",
               (visws_board_type == VISWS_320 ? "320" :
               (visws_board_type == VISWS_540 ? "540" :
                "unknown")), visws_board_rev);
}

#define A01234 (LI_INTA_0 | LI_INTA_1 | LI_INTA_2 | LI_INTA_3 | LI_INTA_4)
#define BCD (LI_INTB | LI_INTC | LI_INTD)
#define ALLDEVS (A01234 | BCD)

static __init void lithium_init(void)
{
        set_fixmap(FIX_LI_PCIA, LI_PCI_A_PHYS);
        set_fixmap(FIX_LI_PCIB, LI_PCI_B_PHYS);

        if ((li_pcia_read16(PCI_VENDOR_ID) != PCI_VENDOR_ID_SGI) ||
            (li_pcia_read16(PCI_DEVICE_ID) != PCI_DEVICE_ID_SGI_LITHIUM)) {
                printk(KERN_EMERG "Lithium hostbridge %c not found\n", 'A');
/*              panic("This machine is not SGI Visual Workstation 320/540"); */
        }

        if ((li_pcib_read16(PCI_VENDOR_ID) != PCI_VENDOR_ID_SGI) ||
            (li_pcib_read16(PCI_DEVICE_ID) != PCI_DEVICE_ID_SGI_LITHIUM)) {
                printk(KERN_EMERG "Lithium hostbridge %c not found\n", 'B');
/*              panic("This machine is not SGI Visual Workstation 320/540"); */
        }

        li_pcia_write16(LI_PCI_INTEN, ALLDEVS);
        li_pcib_write16(LI_PCI_INTEN, ALLDEVS);
}

static __init void cobalt_init(void)
{
        /*
         * On normal SMP PC this is used only with SMP, but we have to
         * use it and set it up here to start the Cobalt clock
         */
        set_fixmap(FIX_APIC_BASE, APIC_DEFAULT_PHYS_BASE);
        setup_local_APIC();
        printk(KERN_INFO "Local APIC Version %#x, ID %#x\n",
                (unsigned int)apic_read(APIC_LVR),
                (unsigned int)apic_read(APIC_ID));

        set_fixmap(FIX_CO_CPU, CO_CPU_PHYS);
        set_fixmap(FIX_CO_APIC, CO_APIC_PHYS);
        printk(KERN_INFO "Cobalt Revision %#lx, APIC ID %#lx\n",
                co_cpu_read(CO_CPU_REV), co_apic_read(CO_APIC_ID));

        /* Enable Cobalt APIC being careful to NOT change the ID! */
        co_apic_write(CO_APIC_ID, co_apic_read(CO_APIC_ID) | CO_APIC_ENABLE);

        printk(KERN_INFO "Cobalt APIC enabled: ID reg %#lx\n",
                co_apic_read(CO_APIC_ID));
}

static void __init visws_trap_init(void)
{
        lithium_init();
        cobalt_init();
}

/*
 * IRQ controller / APIC support:
 */

static DEFINE_SPINLOCK(cobalt_lock);

/*
 * Set the given Cobalt APIC Redirection Table entry to point
 * to the given IDT vector/index.
 */
static inline void co_apic_set(int entry, int irq)
{
        co_apic_write(CO_APIC_LO(entry), CO_APIC_LEVEL | (irq + FIRST_EXTERNAL_VECTOR));
        co_apic_write(CO_APIC_HI(entry), 0);
}

/*
 * Cobalt (IO)-APIC functions to handle PCI devices.
 */
static inline int co_apic_ide0_hack(void)
{
        extern char visws_board_type;
        extern char visws_board_rev;

        if (visws_board_type == VISWS_320 && visws_board_rev == 5)
                return 5;
        return CO_APIC_IDE0;
}

static int is_co_apic(unsigned int irq)
{
        if (IS_CO_APIC(irq))
                return CO_APIC(irq);

        switch (irq) {
                case 0: return CO_APIC_CPU;
                case CO_IRQ_IDE0: return co_apic_ide0_hack();
                case CO_IRQ_IDE1: return CO_APIC_IDE1;
                default: return -1;
        }
}


/*
 * This is the SGI Cobalt (IO-)APIC:
 */
static void enable_cobalt_irq(struct irq_data *data)
{
        co_apic_set(is_co_apic(data->irq), data->irq);
}

static void disable_cobalt_irq(struct irq_data *data)
{
        int entry = is_co_apic(data->irq);

        co_apic_write(CO_APIC_LO(entry), CO_APIC_MASK);
        co_apic_read(CO_APIC_LO(entry));
}

static void ack_cobalt_irq(struct irq_data *data)
{
        unsigned long flags;

        spin_lock_irqsave(&cobalt_lock, flags);
        disable_cobalt_irq(data);
        apic_write(APIC_EOI, APIC_EOI_ACK);
        spin_unlock_irqrestore(&cobalt_lock, flags);
}

static struct irq_chip cobalt_irq_type = {
        .name           = "Cobalt-APIC",
        .irq_enable     = enable_cobalt_irq,
        .irq_disable    = disable_cobalt_irq,
        .irq_ack        = ack_cobalt_irq,
};


/*
 * This is the PIIX4-based 8259 that is wired up indirectly to Cobalt
 * -- not the manner expected by the code in i8259.c.
 *
 * there is a 'master' physical interrupt source that gets sent to
 * the CPU. But in the chipset there are various 'virtual' interrupts
 * waiting to be handled. We represent this to Linux through a 'master'
 * interrupt controller type, and through a special virtual interrupt-
 * controller. Device drivers only see the virtual interrupt sources.
 */
static unsigned int startup_piix4_master_irq(struct irq_data *data)
{
        legacy_pic->init(0);
        enable_cobalt_irq(data);
        return 0;
}

static struct irq_chip piix4_master_irq_type = {
        .name           = "PIIX4-master",
        .irq_startup    = startup_piix4_master_irq,
        .irq_ack        = ack_cobalt_irq,
};

static void pii4_mask(struct irq_data *data) { }

static struct irq_chip piix4_virtual_irq_type = {
        .name           = "PIIX4-virtual",
        .irq_mask       = pii4_mask,
};

/*
 * PIIX4-8259 master/virtual functions to handle interrupt requests
 * from legacy devices: floppy, parallel, serial, rtc.
 *
 * None of these get Cobalt APIC entries, neither do they have IDT
 * entries. These interrupts are purely virtual and distributed from
 * the 'master' interrupt source: CO_IRQ_8259.
 *
 * When the 8259 interrupts its handler figures out which of these
 * devices is interrupting and dispatches to its handler.
 *
 * CAREFUL: devices see the 'virtual' interrupt only. Thus disable/
 * enable_irq gets the right irq. This 'master' irq is never directly
 * manipulated by any driver.
 */
static irqreturn_t piix4_master_intr(int irq, void *dev_id)
{
        unsigned long flags;
        int realirq;

        raw_spin_lock_irqsave(&i8259A_lock, flags);

        /* Find out what's interrupting in the PIIX4 master 8259 */
        outb(0x0c, 0x20);               /* OCW3 Poll command */
        realirq = inb(0x20);

        /*
         * Bit 7 == 0 means invalid/spurious
         */
        if (unlikely(!(realirq & 0x80)))
                goto out_unlock;

        realirq &= 7;

        if (unlikely(realirq == 2)) {
                outb(0x0c, 0xa0);
                realirq = inb(0xa0);

                if (unlikely(!(realirq & 0x80)))
                        goto out_unlock;

                realirq = (realirq & 7) + 8;
        }

        /* mask and ack interrupt */
        cached_irq_mask |= 1 << realirq;
        if (unlikely(realirq > 7)) {
                inb(0xa1);
                outb(cached_slave_mask, 0xa1);
                outb(0x60 + (realirq & 7), 0xa0);
                outb(0x60 + 2, 0x20);
        } else {
                inb(0x21);
                outb(cached_master_mask, 0x21);
                outb(0x60 + realirq, 0x20);
        }

        raw_spin_unlock_irqrestore(&i8259A_lock, flags);

        /*
         * handle this 'virtual interrupt' as a Cobalt one now.
         */
        generic_handle_irq(realirq);

        return IRQ_HANDLED;

out_unlock:
        raw_spin_unlock_irqrestore(&i8259A_lock, flags);
        return IRQ_NONE;
}

static struct irqaction master_action = {
        .handler =      piix4_master_intr,
        .name =         "PIIX4-8259",
        .flags =        IRQF_NO_THREAD,
};

static struct irqaction cascade_action = {
        .handler =      no_action,
        .name =         "cascade",
        .flags =        IRQF_NO_THREAD,
};

static inline void set_piix4_virtual_irq_type(void)
{
        piix4_virtual_irq_type.irq_enable = i8259A_chip.irq_unmask;
        piix4_virtual_irq_type.irq_disable = i8259A_chip.irq_mask;
        piix4_virtual_irq_type.irq_unmask = i8259A_chip.irq_unmask;
}

static void __init visws_pre_intr_init(void)
{
        int i;

        set_piix4_virtual_irq_type();

        for (i = 0; i < CO_IRQ_APIC0 + CO_APIC_LAST + 1; i++) {
                struct irq_chip *chip = NULL;

                if (i == 0)
                        chip = &cobalt_irq_type;
                else if (i == CO_IRQ_IDE0)
                        chip = &cobalt_irq_type;
                else if (i == CO_IRQ_IDE1)
                        chip = &cobalt_irq_type;
                else if (i == CO_IRQ_8259)
                        chip = &piix4_master_irq_type;
                else if (i < CO_IRQ_APIC0)
                        chip = &piix4_virtual_irq_type;
                else if (IS_CO_APIC(i))
                        chip = &cobalt_irq_type;

                if (chip)
                        irq_set_chip(i, chip);
        }

        setup_irq(CO_IRQ_8259, &master_action);
        setup_irq(2, &cascade_action);
}