sys_jensen.c

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/*
 *  linux/arch/alpha/kernel/sys_jensen.c
 *
 *  Copyright (C) 1995 Linus Torvalds
 *  Copyright (C) 1998, 1999 Richard Henderson
 *
 * Code supporting the Jensen.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/init.h>

#include <asm/ptrace.h>

#define __EXTERN_INLINE inline
#include <asm/io.h>
#include <asm/jensen.h>
#undef  __EXTERN_INLINE

#include <asm/dma.h>
#include <asm/irq.h>
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>

#include "proto.h"
#include "irq_impl.h"
#include "pci_impl.h"
#include "machvec_impl.h"


/*
 * Jensen is special: the vector is 0x8X0 for EISA interrupt X, and
 * 0x9X0 for the local motherboard interrupts.
 *
 * Note especially that those local interrupts CANNOT be masked,
 * which causes much of the pain below...
 *
 *  0x660 - NMI
 *
 *  0x800 - IRQ0  interval timer (not used, as we use the RTC timer)
 *  0x810 - IRQ1  line printer (duh..)
 *  0x860 - IRQ6  floppy disk
 *
 *  0x900 - COM1
 *  0x920 - COM2
 *  0x980 - keyboard
 *  0x990 - mouse
 *
 * PCI-based systems are more sane: they don't have the local
 * interrupts at all, and have only normal PCI interrupts from
 * devices.  Happily it's easy enough to do a sane mapping from the
 * Jensen.
 * 
 * Note that this means that we may have to do a hardware
 * "local_op" to a different interrupt than we report to the rest of the
 * world.
 */

static void
jensen_local_enable(struct irq_data *d)
{
    /* the parport is really hw IRQ 1, silly Jensen.  */
    if (d->irq == 7)
        i8259a_enable_irq(d);
}

static void
jensen_local_disable(struct irq_data *d)
{
    /* the parport is really hw IRQ 1, silly Jensen.  */
    if (d->irq == 7)
        i8259a_disable_irq(d);
}

static void
jensen_local_mask_ack(struct irq_data *d)
{
    /* the parport is really hw IRQ 1, silly Jensen.  */
    if (d->irq == 7)
        i8259a_mask_and_ack_irq(d);
}

static struct irq_chip jensen_local_irq_type = {
    .name       = "LOCAL",
    .irq_unmask = jensen_local_enable,
    .irq_mask   = jensen_local_disable,
    .irq_mask_ack   = jensen_local_mask_ack,
};

static void 
jensen_device_interrupt(unsigned long vector)
{
    int irq;

    switch (vector) {
    case 0x660:
        printk("Whee.. NMI received. Probable hardware error\n");
        printk("61=%02x, 461=%02x\n", inb(0x61), inb(0x461));
        return;

    /* local device interrupts: */
    case 0x900: irq = 4; break;     /* com1 -> irq 4 */
    case 0x920: irq = 3; break;     /* com2 -> irq 3 */
    case 0x980: irq = 1; break;     /* kbd -> irq 1 */
    case 0x990: irq = 9; break;     /* mouse -> irq 9 */

    default:
        if (vector > 0x900) {
            printk("Unknown local interrupt %lx\n", vector);
            return;
        }

        irq = (vector - 0x800) >> 4;
        if (irq == 1)
            irq = 7;
        break;
    }

    /* If there is no handler yet... */
    if (!irq_has_action(irq)) {
        /* If it is a local interrupt that cannot be masked... */
        if (vector >= 0x900)
        {
            /* Clear keyboard/mouse state */
            inb(0x64);
        inb(0x60);
        /* Reset serial ports */
        inb(0x3fa);
        inb(0x2fa);
        outb(0x0c, 0x3fc);
        outb(0x0c, 0x2fc);
        /* Clear NMI */
        outb(0,0x61);
        outb(0,0x461);
        }
    }

#if 0
        /* A useful bit of code to find out if an interrupt is going wild.  */
        {
          static unsigned int last_msg = 0, last_cc = 0;
          static int last_irq = -1, count = 0;
          unsigned int cc;

          __asm __volatile("rpcc %0" : "=r"(cc));
          ++count;
#define JENSEN_CYCLES_PER_SEC   (150000000)
          if (cc - last_msg > ((JENSEN_CYCLES_PER_SEC) * 3) ||
          irq != last_irq) {
                printk(KERN_CRIT " irq %d count %d cc %u @ %lx\n",
                       irq, count, cc-last_cc, get_irq_regs()->pc);
                count = 0;
                last_msg = cc;
                last_irq = irq;
          }
          last_cc = cc;
        }
#endif

    handle_irq(irq);
}

static void __init
jensen_init_irq(void)
{
    init_i8259a_irqs();

    irq_set_chip_and_handler(1, &jensen_local_irq_type, handle_level_irq);
    irq_set_chip_and_handler(4, &jensen_local_irq_type, handle_level_irq);
    irq_set_chip_and_handler(3, &jensen_local_irq_type, handle_level_irq);
    irq_set_chip_and_handler(7, &jensen_local_irq_type, handle_level_irq);
    irq_set_chip_and_handler(9, &jensen_local_irq_type, handle_level_irq);

    common_init_isa_dma();
}

static void __init
jensen_init_arch(void)
{
    struct pci_controller *hose;
#ifdef CONFIG_PCI
    static struct pci_dev fake_isa_bridge = { .dma_mask = 0xffffffffUL, };

    isa_bridge = &fake_isa_bridge;
#endif

    /* Create a hose so that we can report i/o base addresses to
       userland.  */

    pci_isa_hose = hose = alloc_pci_controller();
    hose->io_space = &ioport_resource;
    hose->mem_space = &iomem_resource;
    hose->index = 0;

    hose->sparse_mem_base = EISA_MEM - IDENT_ADDR;
    hose->dense_mem_base = 0;
    hose->sparse_io_base = EISA_IO - IDENT_ADDR;
    hose->dense_io_base = 0;

    hose->sg_isa = hose->sg_pci = NULL;
    __direct_map_base = 0;
    __direct_map_size = 0xffffffff;
}

static void
jensen_machine_check(unsigned long vector, unsigned long la)
{
    printk(KERN_CRIT "Machine check\n");
}

/*
 * The System Vector
 */

struct alpha_machine_vector jensen_mv __initmv = {
    .vector_name        = "Jensen",
    DO_EV4_MMU,
    IO_LITE(JENSEN,jensen),
    .machine_check      = jensen_machine_check,
    .max_isa_dma_address    = ALPHA_MAX_ISA_DMA_ADDRESS,
    .rtc_port       = 0x170,
    .rtc_get_time       = common_get_rtc_time,
    .rtc_set_time       = common_set_rtc_time,

    .nr_irqs        = 16,
    .device_interrupt   = jensen_device_interrupt,

    .init_arch      = jensen_init_arch,
    .init_irq       = jensen_init_irq,
    .init_rtc       = common_init_rtc,
    .init_pci       = NULL,
    .kill_arch      = NULL,
};
ALIAS_MV(jensen)