[TG3]: Set minimal hw interrupt mitigation.

[linux-2.6/verdex.git] / arch / sparc / kernel / sun4m_irq.c

/*  sun4m_irq.c
 *  arch/sparc/kernel/sun4m_irq.c:
 *
 *  djhr: Hacked out of irq.c into a CPU dependent version.
 *
 *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 *  Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
 *  Copyright (C) 1995 Pete A. Zaitcev (zaitcev@yahoo.com)
 *  Copyright (C) 1996 Dave Redman (djhr@tadpole.co.uk)
 */

#include <linux/config.h>
#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/kernel_stat.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/ioport.h>

#include <asm/ptrace.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/psr.h>
#include <asm/vaddrs.h>
#include <asm/timer.h>
#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/traps.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/smp.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/sbus.h>
#include <asm/cacheflush.h>

static unsigned long dummy;

struct sun4m_intregs *sun4m_interrupts;
unsigned long *irq_rcvreg = &dummy;

/* These tables only apply for interrupts greater than 15..
 * 
 * any intr value below 0x10 is considered to be a soft-int
 * this may be useful or it may not.. but that's how I've done it.
 * and it won't clash with what OBP is telling us about devices.
 *
 * take an encoded intr value and lookup if it's valid
 * then get the mask bits that match from irq_mask
 *
 * P3: Translation from irq 0x0d to mask 0x2000 is for MrCoffee.
 */
static unsigned char irq_xlate[32] = {
    /*  0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  a,  b,  c,  d,  e,  f */
        0,  0,  0,  0,  1,  0,  2,  0,  3,  0,  4,  5,  6, 14,  0,  7,
        0,  0,  8,  9,  0, 10,  0, 11,  0, 12,  0, 13,  0, 14,  0,  0
};

static unsigned long irq_mask[] = {
        0,                                                /* illegal index */
        SUN4M_INT_SCSI,                                   /*  1 irq 4 */
        SUN4M_INT_ETHERNET,                               /*  2 irq 6 */
        SUN4M_INT_VIDEO,                                  /*  3 irq 8 */
        SUN4M_INT_REALTIME,                               /*  4 irq 10 */
        SUN4M_INT_FLOPPY,                                 /*  5 irq 11 */
        (SUN4M_INT_SERIAL | SUN4M_INT_KBDMS),             /*  6 irq 12 */
        SUN4M_INT_MODULE_ERR,                             /*  7 irq 15 */
        SUN4M_INT_SBUS(0),                                /*  8 irq 2 */
        SUN4M_INT_SBUS(1),                                /*  9 irq 3 */
        SUN4M_INT_SBUS(2),                                /* 10 irq 5 */
        SUN4M_INT_SBUS(3),                                /* 11 irq 7 */
        SUN4M_INT_SBUS(4),                                /* 12 irq 9 */
        SUN4M_INT_SBUS(5),                                /* 13 irq 11 */
        SUN4M_INT_SBUS(6)                                 /* 14 irq 13 */
};

static int sun4m_pil_map[] = { 0, 2, 3, 5, 7, 9, 11, 13 };

unsigned int sun4m_sbint_to_irq(struct sbus_dev *sdev, unsigned int sbint) 
{
        if (sbint >= sizeof(sun4m_pil_map)) {
                printk(KERN_ERR "%s: bogus SBINT %d\n", sdev->prom_name, sbint);
                BUG();
        }
        return sun4m_pil_map[sbint] | 0x30;
}

inline unsigned long sun4m_get_irqmask(unsigned int irq)
{
        unsigned long mask;
    
        if (irq > 0x20) {
                /* OBIO/SBUS interrupts */
                irq &= 0x1f;
                mask = irq_mask[irq_xlate[irq]];
                if (!mask)
                        printk("sun4m_get_irqmask: IRQ%d has no valid mask!\n",irq);
        } else {
                /* Soft Interrupts will come here.
                 * Currently there is no way to trigger them but I'm sure
                 * something could be cooked up.
                 */
                irq &= 0xf;
                mask = SUN4M_SOFT_INT(irq);
        }
        return mask;
}

static void sun4m_disable_irq(unsigned int irq_nr)
{
        unsigned long mask, flags;
        int cpu = smp_processor_id();

        mask = sun4m_get_irqmask(irq_nr);
        local_irq_save(flags);
        if (irq_nr > 15)
                sun4m_interrupts->set = mask;
        else
                sun4m_interrupts->cpu_intregs[cpu].set = mask;
        local_irq_restore(flags);    
}

static void sun4m_enable_irq(unsigned int irq_nr)
{
        unsigned long mask, flags;
        int cpu = smp_processor_id();

        /* Dreadful floppy hack. When we use 0x2b instead of
         * 0x0b the system blows (it starts to whistle!).
         * So we continue to use 0x0b. Fixme ASAP. --P3
         */
        if (irq_nr != 0x0b) {
                mask = sun4m_get_irqmask(irq_nr);
                local_irq_save(flags);
                if (irq_nr > 15)
                        sun4m_interrupts->clear = mask;
                else
                        sun4m_interrupts->cpu_intregs[cpu].clear = mask;
                local_irq_restore(flags);    
        } else {
                local_irq_save(flags);
                sun4m_interrupts->clear = SUN4M_INT_FLOPPY;
                local_irq_restore(flags);
        }
}

static unsigned long cpu_pil_to_imask[16] = {
/*0*/   0x00000000,
/*1*/   0x00000000,
/*2*/   SUN4M_INT_SBUS(0) | SUN4M_INT_VME(0),
/*3*/   SUN4M_INT_SBUS(1) | SUN4M_INT_VME(1),
/*4*/   SUN4M_INT_SCSI,
/*5*/   SUN4M_INT_SBUS(2) | SUN4M_INT_VME(2),
/*6*/   SUN4M_INT_ETHERNET,
/*7*/   SUN4M_INT_SBUS(3) | SUN4M_INT_VME(3),
/*8*/   SUN4M_INT_VIDEO,
/*9*/   SUN4M_INT_SBUS(4) | SUN4M_INT_VME(4) | SUN4M_INT_MODULE_ERR,
/*10*/  SUN4M_INT_REALTIME,
/*11*/  SUN4M_INT_SBUS(5) | SUN4M_INT_VME(5) | SUN4M_INT_FLOPPY,
/*12*/  SUN4M_INT_SERIAL | SUN4M_INT_KBDMS,
/*13*/  SUN4M_INT_AUDIO,
/*14*/  SUN4M_INT_E14,
/*15*/  0x00000000
};

/* We assume the caller has disabled local interrupts when these are called,
 * or else very bizarre behavior will result.
 */
static void sun4m_disable_pil_irq(unsigned int pil)
{
        sun4m_interrupts->set = cpu_pil_to_imask[pil];
}

static void sun4m_enable_pil_irq(unsigned int pil)
{
        sun4m_interrupts->clear = cpu_pil_to_imask[pil];
}

#ifdef CONFIG_SMP
static void sun4m_send_ipi(int cpu, int level)
{
        unsigned long mask;

        mask = sun4m_get_irqmask(level);
        sun4m_interrupts->cpu_intregs[cpu].set = mask;
}

static void sun4m_clear_ipi(int cpu, int level)
{
        unsigned long mask;

        mask = sun4m_get_irqmask(level);
        sun4m_interrupts->cpu_intregs[cpu].clear = mask;
}

static void sun4m_set_udt(int cpu)
{
        sun4m_interrupts->undirected_target = cpu;
}
#endif

#define OBIO_INTR       0x20
#define TIMER_IRQ       (OBIO_INTR | 10)
#define PROFILE_IRQ     (OBIO_INTR | 14)

struct sun4m_timer_regs *sun4m_timers;
unsigned int lvl14_resolution = (((1000000/HZ) + 1) << 10);

static void sun4m_clear_clock_irq(void)
{
        volatile unsigned int clear_intr;
        clear_intr = sun4m_timers->l10_timer_limit;
}

static void sun4m_clear_profile_irq(int cpu)
{
        volatile unsigned int clear;
    
        clear = sun4m_timers->cpu_timers[cpu].l14_timer_limit;
}

static void sun4m_load_profile_irq(int cpu, unsigned int limit)
{
        sun4m_timers->cpu_timers[cpu].l14_timer_limit = limit;
}

char *sun4m_irq_itoa(unsigned int irq)
{
        static char buff[16];
        sprintf(buff, "%d", irq);
        return buff;
}

static void __init sun4m_init_timers(irqreturn_t (*counter_fn)(int, void *, struct pt_regs *))
{
        int reg_count, irq, cpu;
        struct linux_prom_registers cnt_regs[PROMREG_MAX];
        int obio_node, cnt_node;
        struct resource r;

        cnt_node = 0;
        if((obio_node =
            prom_searchsiblings (prom_getchild(prom_root_node), "obio")) == 0 ||
           (obio_node = prom_getchild (obio_node)) == 0 ||
           (cnt_node = prom_searchsiblings (obio_node, "counter")) == 0) {
                prom_printf("Cannot find /obio/counter node\n");
                prom_halt();
        }
        reg_count = prom_getproperty(cnt_node, "reg",
                                     (void *) cnt_regs, sizeof(cnt_regs));
        reg_count = (reg_count/sizeof(struct linux_prom_registers));
    
        /* Apply the obio ranges to the timer registers. */
        prom_apply_obio_ranges(cnt_regs, reg_count);
    
        cnt_regs[4].phys_addr = cnt_regs[reg_count-1].phys_addr;
        cnt_regs[4].reg_size = cnt_regs[reg_count-1].reg_size;
        cnt_regs[4].which_io = cnt_regs[reg_count-1].which_io;
        for(obio_node = 1; obio_node < 4; obio_node++) {
                cnt_regs[obio_node].phys_addr =
                        cnt_regs[obio_node-1].phys_addr + PAGE_SIZE;
                cnt_regs[obio_node].reg_size = cnt_regs[obio_node-1].reg_size;
                cnt_regs[obio_node].which_io = cnt_regs[obio_node-1].which_io;
        }

        memset((char*)&r, 0, sizeof(struct resource));
        /* Map the per-cpu Counter registers. */
        r.flags = cnt_regs[0].which_io;
        r.start = cnt_regs[0].phys_addr;
        sun4m_timers = (struct sun4m_timer_regs *) sbus_ioremap(&r, 0,
            PAGE_SIZE*SUN4M_NCPUS, "sun4m_cpu_cnt");
        /* Map the system Counter register. */
        /* XXX Here we expect consequent calls to yeld adjusent maps. */
        r.flags = cnt_regs[4].which_io;
        r.start = cnt_regs[4].phys_addr;
        sbus_ioremap(&r, 0, cnt_regs[4].reg_size, "sun4m_sys_cnt");

        sun4m_timers->l10_timer_limit =  (((1000000/HZ) + 1) << 10);
        master_l10_counter = &sun4m_timers->l10_cur_count;
        master_l10_limit = &sun4m_timers->l10_timer_limit;

        irq = request_irq(TIMER_IRQ,
                          counter_fn,
                          (SA_INTERRUPT | SA_STATIC_ALLOC),
                          "timer", NULL);
        if (irq) {
                prom_printf("time_init: unable to attach IRQ%d\n",TIMER_IRQ);
                prom_halt();
        }
   
        if (!cpu_find_by_instance(1, NULL, NULL)) {
                for(cpu = 0; cpu < 4; cpu++)
                        sun4m_timers->cpu_timers[cpu].l14_timer_limit = 0;
                sun4m_interrupts->set = SUN4M_INT_E14;
        } else {
                sun4m_timers->cpu_timers[0].l14_timer_limit = 0;
        }
#ifdef CONFIG_SMP
        {
                unsigned long flags;
                extern unsigned long lvl14_save[4];
                struct tt_entry *trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (14 - 1)];

                /* For SMP we use the level 14 ticker, however the bootup code
                 * has copied the firmwares level 14 vector into boot cpu's
                 * trap table, we must fix this now or we get squashed.
                 */
                local_irq_save(flags);
                trap_table->inst_one = lvl14_save[0];
                trap_table->inst_two = lvl14_save[1];
                trap_table->inst_three = lvl14_save[2];
                trap_table->inst_four = lvl14_save[3];
                local_flush_cache_all();
                local_irq_restore(flags);
        }
#endif
}

void __init sun4m_init_IRQ(void)
{
        int ie_node,i;
        struct linux_prom_registers int_regs[PROMREG_MAX];
        int num_regs;
        struct resource r;
        int mid;
    
        local_irq_disable();
        if((ie_node = prom_searchsiblings(prom_getchild(prom_root_node), "obio")) == 0 ||
           (ie_node = prom_getchild (ie_node)) == 0 ||
           (ie_node = prom_searchsiblings (ie_node, "interrupt")) == 0) {
                prom_printf("Cannot find /obio/interrupt node\n");
                prom_halt();
        }
        num_regs = prom_getproperty(ie_node, "reg", (char *) int_regs,
                                    sizeof(int_regs));
        num_regs = (num_regs/sizeof(struct linux_prom_registers));
    
        /* Apply the obio ranges to these registers. */
        prom_apply_obio_ranges(int_regs, num_regs);
    
        int_regs[4].phys_addr = int_regs[num_regs-1].phys_addr;
        int_regs[4].reg_size = int_regs[num_regs-1].reg_size;
        int_regs[4].which_io = int_regs[num_regs-1].which_io;
        for(ie_node = 1; ie_node < 4; ie_node++) {
                int_regs[ie_node].phys_addr = int_regs[ie_node-1].phys_addr + PAGE_SIZE;
                int_regs[ie_node].reg_size = int_regs[ie_node-1].reg_size;
                int_regs[ie_node].which_io = int_regs[ie_node-1].which_io;
        }

        memset((char *)&r, 0, sizeof(struct resource));
        /* Map the interrupt registers for all possible cpus. */
        r.flags = int_regs[0].which_io;
        r.start = int_regs[0].phys_addr;
        sun4m_interrupts = (struct sun4m_intregs *) sbus_ioremap(&r, 0,
            PAGE_SIZE*SUN4M_NCPUS, "interrupts_percpu");

        /* Map the system interrupt control registers. */
        r.flags = int_regs[4].which_io;
        r.start = int_regs[4].phys_addr;
        sbus_ioremap(&r, 0, int_regs[4].reg_size, "interrupts_system");

        sun4m_interrupts->set = ~SUN4M_INT_MASKALL;
        for (i = 0; !cpu_find_by_instance(i, NULL, &mid); i++)
                sun4m_interrupts->cpu_intregs[mid].clear = ~0x17fff;

        if (!cpu_find_by_instance(1, NULL, NULL)) {
                /* system wide interrupts go to cpu 0, this should always
                 * be safe because it is guaranteed to be fitted or OBP doesn't
                 * come up
                 *
                 * Not sure, but writing here on SLAVIO systems may puke
                 * so I don't do it unless there is more than 1 cpu.
                 */
                irq_rcvreg = (unsigned long *)
                                &sun4m_interrupts->undirected_target;
                sun4m_interrupts->undirected_target = 0;
        }
        BTFIXUPSET_CALL(sbint_to_irq, sun4m_sbint_to_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(enable_irq, sun4m_enable_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(disable_irq, sun4m_disable_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(enable_pil_irq, sun4m_enable_pil_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(disable_pil_irq, sun4m_disable_pil_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(clear_clock_irq, sun4m_clear_clock_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(clear_profile_irq, sun4m_clear_profile_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(load_profile_irq, sun4m_load_profile_irq, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(__irq_itoa, sun4m_irq_itoa, BTFIXUPCALL_NORM);
        sparc_init_timers = sun4m_init_timers;
#ifdef CONFIG_SMP
        BTFIXUPSET_CALL(set_cpu_int, sun4m_send_ipi, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(clear_cpu_int, sun4m_clear_ipi, BTFIXUPCALL_NORM);
        BTFIXUPSET_CALL(set_irq_udt, sun4m_set_udt, BTFIXUPCALL_NORM);
#endif
        /* Cannot enable interrupts until OBP ticker is disabled. */
}