Linux-2.6.12-rc2

[linux-2.6/kvm.git] / arch / ppc / platforms / pmac_smp.c

/*
 * SMP support for power macintosh.
 *
 * We support both the old "powersurge" SMP architecture
 * and the current Core99 (G4 PowerMac) machines.
 *
 * Note that we don't support the very first rev. of
 * Apple/DayStar 2 CPUs board, the one with the funky
 * watchdog. Hopefully, none of these should be there except
 * maybe internally to Apple. I should probably still add some
 * code to detect this card though and disable SMP. --BenH.
 *
 * Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
 * and Ben Herrenschmidt <benh@kernel.crashing.org>.
 *
 * Support for DayStar quad CPU cards
 * Copyright (C) XLR8, Inc. 1994-2000
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 */
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/hardirq.h>

#include <asm/ptrace.h>
#include <asm/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/residual.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/time.h>
#include <asm/open_pic.h>
#include <asm/cacheflush.h>
#include <asm/keylargo.h>

/*
 * Powersurge (old powermac SMP) support.
 */

extern void __secondary_start_psurge(void);
extern void __secondary_start_psurge2(void);    /* Temporary horrible hack */
extern void __secondary_start_psurge3(void);    /* Temporary horrible hack */

/* Addresses for powersurge registers */
#define HAMMERHEAD_BASE         0xf8000000
#define HHEAD_CONFIG            0x90
#define HHEAD_SEC_INTR          0xc0

/* register for interrupting the primary processor on the powersurge */
/* N.B. this is actually the ethernet ROM! */
#define PSURGE_PRI_INTR         0xf3019000

/* register for storing the start address for the secondary processor */
/* N.B. this is the PCI config space address register for the 1st bridge */
#define PSURGE_START            0xf2800000

/* Daystar/XLR8 4-CPU card */
#define PSURGE_QUAD_REG_ADDR    0xf8800000

#define PSURGE_QUAD_IRQ_SET     0
#define PSURGE_QUAD_IRQ_CLR     1
#define PSURGE_QUAD_IRQ_PRIMARY 2
#define PSURGE_QUAD_CKSTOP_CTL  3
#define PSURGE_QUAD_PRIMARY_ARB 4
#define PSURGE_QUAD_BOARD_ID    6
#define PSURGE_QUAD_WHICH_CPU   7
#define PSURGE_QUAD_CKSTOP_RDBK 8
#define PSURGE_QUAD_RESET_CTL   11

#define PSURGE_QUAD_OUT(r, v)   (out_8(quad_base + ((r) << 4) + 4, (v)))
#define PSURGE_QUAD_IN(r)       (in_8(quad_base + ((r) << 4) + 4) & 0x0f)
#define PSURGE_QUAD_BIS(r, v)   (PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
#define PSURGE_QUAD_BIC(r, v)   (PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))

/* virtual addresses for the above */
static volatile u8 *hhead_base;
static volatile u8 *quad_base;
static volatile u32 *psurge_pri_intr;
static volatile u8 *psurge_sec_intr;
static volatile u32 *psurge_start;

/* values for psurge_type */
#define PSURGE_NONE             -1
#define PSURGE_DUAL             0
#define PSURGE_QUAD_OKEE        1
#define PSURGE_QUAD_COTTON      2
#define PSURGE_QUAD_ICEGRASS    3

/* what sort of powersurge board we have */
static int psurge_type = PSURGE_NONE;

/* L2 and L3 cache settings to pass from CPU0 to CPU1 */
volatile static long int core99_l2_cache;
volatile static long int core99_l3_cache;

/* Timebase freeze GPIO */
static unsigned int core99_tb_gpio;

/* Sync flag for HW tb sync */
static volatile int sec_tb_reset = 0;

static void __init core99_init_caches(int cpu)
{
        if (!cpu_has_feature(CPU_FTR_L2CR))
                return;

        if (cpu == 0) {
                core99_l2_cache = _get_L2CR();
                printk("CPU0: L2CR is %lx\n", core99_l2_cache);
        } else {
                printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
                _set_L2CR(0);
                _set_L2CR(core99_l2_cache);
                printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
        }

        if (!cpu_has_feature(CPU_FTR_L3CR))
                return;

        if (cpu == 0){
                core99_l3_cache = _get_L3CR();
                printk("CPU0: L3CR is %lx\n", core99_l3_cache);
        } else {
                printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
                _set_L3CR(0);
                _set_L3CR(core99_l3_cache);
                printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
        }
}

/*
 * Set and clear IPIs for powersurge.
 */
static inline void psurge_set_ipi(int cpu)
{
        if (psurge_type == PSURGE_NONE)
                return;
        if (cpu == 0)
                in_be32(psurge_pri_intr);
        else if (psurge_type == PSURGE_DUAL)
                out_8(psurge_sec_intr, 0);
        else
                PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
}

static inline void psurge_clr_ipi(int cpu)
{
        if (cpu > 0) {
                switch(psurge_type) {
                case PSURGE_DUAL:
                        out_8(psurge_sec_intr, ~0);
                case PSURGE_NONE:
                        break;
                default:
                        PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
                }
        }
}

/*
 * On powersurge (old SMP powermac architecture) we don't have
 * separate IPIs for separate messages like openpic does.  Instead
 * we have a bitmap for each processor, where a 1 bit means that
 * the corresponding message is pending for that processor.
 * Ideally each cpu's entry would be in a different cache line.
 *  -- paulus.
 */
static unsigned long psurge_smp_message[NR_CPUS];

void __pmac psurge_smp_message_recv(struct pt_regs *regs)
{
        int cpu = smp_processor_id();
        int msg;

        /* clear interrupt */
        psurge_clr_ipi(cpu);

        if (num_online_cpus() < 2)
                return;

        /* make sure there is a message there */
        for (msg = 0; msg < 4; msg++)
                if (test_and_clear_bit(msg, &psurge_smp_message[cpu]))
                        smp_message_recv(msg, regs);
}

irqreturn_t __pmac psurge_primary_intr(int irq, void *d, struct pt_regs *regs)
{
        psurge_smp_message_recv(regs);
        return IRQ_HANDLED;
}

static void __pmac smp_psurge_message_pass(int target, int msg, unsigned long data,
                                           int wait)
{
        int i;

        if (num_online_cpus() < 2)
                return;

        for (i = 0; i < NR_CPUS; i++) {
                if (!cpu_online(i))
                        continue;
                if (target == MSG_ALL
                    || (target == MSG_ALL_BUT_SELF && i != smp_processor_id())
                    || target == i) {
                        set_bit(msg, &psurge_smp_message[i]);
                        psurge_set_ipi(i);
                }
        }
}

/*
 * Determine a quad card presence. We read the board ID register, we
 * force the data bus to change to something else, and we read it again.
 * It it's stable, then the register probably exist (ugh !)
 */
static int __init psurge_quad_probe(void)
{
        int type;
        unsigned int i;

        type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
        if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
            || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
                return PSURGE_DUAL;

        /* looks OK, try a slightly more rigorous test */
        /* bogus is not necessarily cacheline-aligned,
           though I don't suppose that really matters.  -- paulus */
        for (i = 0; i < 100; i++) {
                volatile u32 bogus[8];
                bogus[(0+i)%8] = 0x00000000;
                bogus[(1+i)%8] = 0x55555555;
                bogus[(2+i)%8] = 0xFFFFFFFF;
                bogus[(3+i)%8] = 0xAAAAAAAA;
                bogus[(4+i)%8] = 0x33333333;
                bogus[(5+i)%8] = 0xCCCCCCCC;
                bogus[(6+i)%8] = 0xCCCCCCCC;
                bogus[(7+i)%8] = 0x33333333;
                wmb();
                asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
                mb();
                if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
                        return PSURGE_DUAL;
        }
        return type;
}

static void __init psurge_quad_init(void)
{
        int procbits;

        if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
        procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
        if (psurge_type == PSURGE_QUAD_ICEGRASS)
                PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
        else
                PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
        mdelay(33);
        out_8(psurge_sec_intr, ~0);
        PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
        PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
        if (psurge_type != PSURGE_QUAD_ICEGRASS)
                PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
        PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
        mdelay(33);
        PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
        mdelay(33);
        PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
        mdelay(33);
}

static int __init smp_psurge_probe(void)
{
        int i, ncpus;

        /* We don't do SMP on the PPC601 -- paulus */
        if (PVR_VER(mfspr(SPRN_PVR)) == 1)
                return 1;

        /*
         * The powersurge cpu board can be used in the generation
         * of powermacs that have a socket for an upgradeable cpu card,
         * including the 7500, 8500, 9500, 9600.
         * The device tree doesn't tell you if you have 2 cpus because
         * OF doesn't know anything about the 2nd processor.
         * Instead we look for magic bits in magic registers,
         * in the hammerhead memory controller in the case of the
         * dual-cpu powersurge board.  -- paulus.
         */
        if (find_devices("hammerhead") == NULL)
                return 1;

        hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
        quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
        psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;

        psurge_type = psurge_quad_probe();
        if (psurge_type != PSURGE_DUAL) {
                psurge_quad_init();
                /* All released cards using this HW design have 4 CPUs */
                ncpus = 4;
        } else {
                iounmap((void *) quad_base);
                if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
                        /* not a dual-cpu card */
                        iounmap((void *) hhead_base);
                        psurge_type = PSURGE_NONE;
                        return 1;
                }
                ncpus = 2;
        }

        psurge_start = ioremap(PSURGE_START, 4);
        psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);

        /* this is not actually strictly necessary -- paulus. */
        for (i = 1; i < ncpus; ++i)
                smp_hw_index[i] = i;

        if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);

        return ncpus;
}

static void __init smp_psurge_kick_cpu(int nr)
{
        void (*start)(void) = __secondary_start_psurge;
        unsigned long a;

        /* may need to flush here if secondary bats aren't setup */
        for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
                asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
        asm volatile("sync");

        if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);

        /* setup entry point of secondary processor */
        switch (nr) {
        case 2:
                start = __secondary_start_psurge2;
                break;
        case 3:
                start = __secondary_start_psurge3;
                break;
        }

        out_be32(psurge_start, __pa(start));
        mb();

        psurge_set_ipi(nr);
        udelay(10);
        psurge_clr_ipi(nr);

        if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
}

/*
 * With the dual-cpu powersurge board, the decrementers and timebases
 * of both cpus are frozen after the secondary cpu is started up,
 * until we give the secondary cpu another interrupt.  This routine
 * uses this to get the timebases synchronized.
 *  -- paulus.
 */
static void __init psurge_dual_sync_tb(int cpu_nr)
{
        int t;

        set_dec(tb_ticks_per_jiffy);
        set_tb(0, 0);
        last_jiffy_stamp(cpu_nr) = 0;

        if (cpu_nr > 0) {
                mb();
                sec_tb_reset = 1;
                return;
        }

        /* wait for the secondary to have reset its TB before proceeding */
        for (t = 10000000; t > 0 && !sec_tb_reset; --t)
                ;

        /* now interrupt the secondary, starting both TBs */
        psurge_set_ipi(1);

        smp_tb_synchronized = 1;
}

static struct irqaction psurge_irqaction = {
        .handler = psurge_primary_intr,
        .flags = SA_INTERRUPT,
        .mask = CPU_MASK_NONE,
        .name = "primary IPI",
};

static void __init smp_psurge_setup_cpu(int cpu_nr)
{

        if (cpu_nr == 0) {
                /* If we failed to start the second CPU, we should still
                 * send it an IPI to start the timebase & DEC or we might
                 * have them stuck.
                 */
                if (num_online_cpus() < 2) {
                        if (psurge_type == PSURGE_DUAL)
                                psurge_set_ipi(1);
                        return;
                }
                /* reset the entry point so if we get another intr we won't
                 * try to startup again */
                out_be32(psurge_start, 0x100);
                if (setup_irq(30, &psurge_irqaction))
                        printk(KERN_ERR "Couldn't get primary IPI interrupt");
        }

        if (psurge_type == PSURGE_DUAL)
                psurge_dual_sync_tb(cpu_nr);
}

void __init smp_psurge_take_timebase(void)
{
        /* Dummy implementation */
}

void __init smp_psurge_give_timebase(void)
{
        /* Dummy implementation */
}

static int __init smp_core99_probe(void)
{
#ifdef CONFIG_6xx
        extern int powersave_nap;
#endif
        struct device_node *cpus, *firstcpu;
        int i, ncpus = 0, boot_cpu = -1;
        u32 *tbprop;

        if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
        cpus = firstcpu = find_type_devices("cpu");
        while(cpus != NULL) {
                u32 *regprop = (u32 *)get_property(cpus, "reg", NULL);
                char *stateprop = (char *)get_property(cpus, "state", NULL);
                if (regprop != NULL && stateprop != NULL &&
                    !strncmp(stateprop, "running", 7))
                        boot_cpu = *regprop;
                ++ncpus;
                cpus = cpus->next;
        }
        if (boot_cpu == -1)
                printk(KERN_WARNING "Couldn't detect boot CPU !\n");
        if (boot_cpu != 0)
                printk(KERN_WARNING "Boot CPU is %d, unsupported setup !\n", boot_cpu);

        if (machine_is_compatible("MacRISC4")) {
                extern struct smp_ops_t core99_smp_ops;

                core99_smp_ops.take_timebase = smp_generic_take_timebase;
                core99_smp_ops.give_timebase = smp_generic_give_timebase;
        } else {
                if (firstcpu != NULL)
                        tbprop = (u32 *)get_property(firstcpu, "timebase-enable", NULL);
                if (tbprop)
                        core99_tb_gpio = *tbprop;
                else
                        core99_tb_gpio = KL_GPIO_TB_ENABLE;
        }

        if (ncpus > 1) {
                openpic_request_IPIs();
                for (i = 1; i < ncpus; ++i)
                        smp_hw_index[i] = i;
#ifdef CONFIG_6xx
                powersave_nap = 0;
#endif
                core99_init_caches(0);
        }

        return ncpus;
}

static void __init smp_core99_kick_cpu(int nr)
{
        unsigned long save_vector, new_vector;
        unsigned long flags;

        volatile unsigned long *vector
                 = ((volatile unsigned long *)(KERNELBASE+0x100));
        if (nr < 1 || nr > 3)
                return;
        if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu", 0x346);

        local_irq_save(flags);
        local_irq_disable();

        /* Save reset vector */
        save_vector = *vector;

        /* Setup fake reset vector that does    
         *   b __secondary_start_psurge - KERNELBASE
         */
        switch(nr) {
                case 1:
                        new_vector = (unsigned long)__secondary_start_psurge;
                        break;
                case 2:
                        new_vector = (unsigned long)__secondary_start_psurge2;
                        break;
                case 3:
                        new_vector = (unsigned long)__secondary_start_psurge3;
                        break;
        }
        *vector = 0x48000002 + new_vector - KERNELBASE;

        /* flush data cache and inval instruction cache */
        flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);

        /* Put some life in our friend */
        pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);

        /* FIXME: We wait a bit for the CPU to take the exception, I should
         * instead wait for the entry code to set something for me. Well,
         * ideally, all that crap will be done in prom.c and the CPU left
         * in a RAM-based wait loop like CHRP.
         */
        mdelay(1);

        /* Restore our exception vector */
        *vector = save_vector;
        flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);

        local_irq_restore(flags);
        if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
}

static void __init smp_core99_setup_cpu(int cpu_nr)
{
        /* Setup L2/L3 */
        if (cpu_nr != 0)
                core99_init_caches(cpu_nr);

        /* Setup openpic */
        do_openpic_setup_cpu();

        if (cpu_nr == 0) {
#ifdef CONFIG_POWER4
                extern void g5_phy_disable_cpu1(void);

                /* If we didn't start the second CPU, we must take
                 * it off the bus
                 */
                if (machine_is_compatible("MacRISC4") &&
                    num_online_cpus() < 2)              
                        g5_phy_disable_cpu1();
#endif /* CONFIG_POWER4 */
                if (ppc_md.progress) ppc_md.progress("core99_setup_cpu 0 done", 0x349);
        }
}

void __init smp_core99_take_timebase(void)
{
        /* Secondary processor "takes" the timebase by freezing
         * it, resetting its local TB and telling CPU 0 to go on
         */
        pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
        pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
        mb();

        set_dec(tb_ticks_per_jiffy);
        set_tb(0, 0);
        last_jiffy_stamp(smp_processor_id()) = 0;

        mb();
        sec_tb_reset = 1;
}

void __init smp_core99_give_timebase(void)
{
        unsigned int t;

        /* Primary processor waits for secondary to have frozen
         * the timebase, resets local TB, and kick timebase again
         */
        /* wait for the secondary to have reset its TB before proceeding */
        for (t = 1000; t > 0 && !sec_tb_reset; --t)
                udelay(1000);
        if (t == 0)
                printk(KERN_WARNING "Timeout waiting sync on second CPU\n");

        set_dec(tb_ticks_per_jiffy);
        set_tb(0, 0);
        last_jiffy_stamp(smp_processor_id()) = 0;
        mb();

        /* Now, restart the timebase by leaving the GPIO to an open collector */
        pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
        pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);

        smp_tb_synchronized = 1;
}


/* PowerSurge-style Macs */
struct smp_ops_t psurge_smp_ops __pmacdata = {
        .message_pass   = smp_psurge_message_pass,
        .probe          = smp_psurge_probe,
        .kick_cpu       = smp_psurge_kick_cpu,
        .setup_cpu      = smp_psurge_setup_cpu,
        .give_timebase  = smp_psurge_give_timebase,
        .take_timebase  = smp_psurge_take_timebase,
};

/* Core99 Macs (dual G4s) */
struct smp_ops_t core99_smp_ops __pmacdata = {
        .message_pass   = smp_openpic_message_pass,
        .probe          = smp_core99_probe,
        .kick_cpu       = smp_core99_kick_cpu,
        .setup_cpu      = smp_core99_setup_cpu,
        .give_timebase  = smp_core99_give_timebase,
        .take_timebase  = smp_core99_take_timebase,
};