common.c

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/*
 * PPC 64 oprofile support:
 * Copyright (C) 2004 Anton Blanchard <[email protected]>, IBM
 * PPC 32 oprofile support: (based on PPC 64 support)
 * Copyright (C) Freescale Semiconductor, Inc 2004
 *  Author: Andy Fleming
 *
 * Based on alpha version.
 *
 * 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/oprofile.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <asm/ptrace.h>
#include <asm/pmc.h>
#include <asm/cputable.h>
#include <asm/oprofile_impl.h>
#include <asm/firmware.h>

static struct op_powerpc_model *model;

static struct op_counter_config ctr[OP_MAX_COUNTER];
static struct op_system_config sys;

static int op_per_cpu_rc;

static void op_handle_interrupt(struct pt_regs *regs)
{
    model->handle_interrupt(regs, ctr);
}

static void op_powerpc_cpu_setup(void *dummy)
{
    int ret;

    ret = model->cpu_setup(ctr);

    if (ret != 0)
        op_per_cpu_rc = ret;
}

static int op_powerpc_setup(void)
{
    int err;

    op_per_cpu_rc = 0;

    /* Grab the hardware */
    err = reserve_pmc_hardware(op_handle_interrupt);
    if (err)
        return err;

    /* Pre-compute the values to stuff in the hardware registers.  */
    op_per_cpu_rc = model->reg_setup(ctr, &sys, model->num_counters);

    if (op_per_cpu_rc)
        goto out;

    /* Configure the registers on all cpus.  If an error occurs on one
     * of the cpus, op_per_cpu_rc will be set to the error */
    on_each_cpu(op_powerpc_cpu_setup, NULL, 1);

out:    if (op_per_cpu_rc) {
        /* error on setup release the performance counter hardware */
        release_pmc_hardware();
    }

    return op_per_cpu_rc;
}

static void op_powerpc_shutdown(void)
{
    release_pmc_hardware();
}

static void op_powerpc_cpu_start(void *dummy)
{
    /* If any of the cpus have return an error, set the
     * global flag to the error so it can be returned
     * to the generic OProfile caller.
     */
    int ret;

    ret = model->start(ctr);
    if (ret != 0)
        op_per_cpu_rc = ret;
}

static int op_powerpc_start(void)
{
    op_per_cpu_rc = 0;

    if (model->global_start)
        return model->global_start(ctr);
    if (model->start) {
        on_each_cpu(op_powerpc_cpu_start, NULL, 1);
        return op_per_cpu_rc;
    }
    return -EIO; /* No start function is defined for this
            power architecture */
}

static inline void op_powerpc_cpu_stop(void *dummy)
{
    model->stop();
}

static void op_powerpc_stop(void)
{
    if (model->stop)
        on_each_cpu(op_powerpc_cpu_stop, NULL, 1);
        if (model->global_stop)
                model->global_stop();
}

static int op_powerpc_create_files(struct super_block *sb, struct dentry *root)
{
    int i;

#ifdef CONFIG_PPC64
    /*
     * There is one mmcr0, mmcr1 and mmcra for setting the events for
     * all of the counters.
     */
    oprofilefs_create_ulong(sb, root, "mmcr0", &sys.mmcr0);
    oprofilefs_create_ulong(sb, root, "mmcr1", &sys.mmcr1);
    oprofilefs_create_ulong(sb, root, "mmcra", &sys.mmcra);
#ifdef CONFIG_OPROFILE_CELL
    /* create a file the user tool can check to see what level of profiling
     * support exits with this kernel. Initialize bit mask to indicate
     * what support the kernel has:
     * bit 0      -  Supports SPU event profiling in addition to PPU
     *               event and cycles; and SPU cycle profiling
     * bits 1-31  -  Currently unused.
     *
     * If the file does not exist, then the kernel only supports SPU
     * cycle profiling, PPU event and cycle profiling.
     */
    oprofilefs_create_ulong(sb, root, "cell_support", &sys.cell_support);
    sys.cell_support = 0x1; /* Note, the user OProfile tool must check
                 * that this bit is set before attempting to
                 * user SPU event profiling.  Older kernels
                 * will not have this file, hence the user
                 * tool is not allowed to do SPU event
                 * profiling on older kernels.  Older kernels
                 * will accept SPU events but collected data
                 * is garbage.
                 */
#endif
#endif

    for (i = 0; i < model->num_counters; ++i) {
        struct dentry *dir;
        char buf[4];

        snprintf(buf, sizeof buf, "%d", i);
        dir = oprofilefs_mkdir(sb, root, buf);

        oprofilefs_create_ulong(sb, dir, "enabled", &ctr[i].enabled);
        oprofilefs_create_ulong(sb, dir, "event", &ctr[i].event);
        oprofilefs_create_ulong(sb, dir, "count", &ctr[i].count);

        /*
         * Classic PowerPC doesn't support per-counter
         * control like this, but the options are
         * expected, so they remain.  For Freescale
         * Book-E style performance monitors, we do
         * support them.
         */
        oprofilefs_create_ulong(sb, dir, "kernel", &ctr[i].kernel);
        oprofilefs_create_ulong(sb, dir, "user", &ctr[i].user);

        oprofilefs_create_ulong(sb, dir, "unit_mask", &ctr[i].unit_mask);
    }

    oprofilefs_create_ulong(sb, root, "enable_kernel", &sys.enable_kernel);
    oprofilefs_create_ulong(sb, root, "enable_user", &sys.enable_user);

    /* Default to tracing both kernel and user */
    sys.enable_kernel = 1;
    sys.enable_user = 1;

    return 0;
}

int __init oprofile_arch_init(struct oprofile_operations *ops)
{
    if (!cur_cpu_spec->oprofile_cpu_type)
        return -ENODEV;

    switch (cur_cpu_spec->oprofile_type) {
#ifdef CONFIG_PPC_BOOK3S_64
#ifdef CONFIG_OPROFILE_CELL
        case PPC_OPROFILE_CELL:
            if (firmware_has_feature(FW_FEATURE_LPAR))
                return -ENODEV;
            model = &op_model_cell;
            ops->sync_start = model->sync_start;
            ops->sync_stop = model->sync_stop;
            break;
#endif
        case PPC_OPROFILE_RS64:
            model = &op_model_rs64;
            break;
        case PPC_OPROFILE_POWER4:
            model = &op_model_power4;
            break;
        case PPC_OPROFILE_PA6T:
            model = &op_model_pa6t;
            break;
#endif
#ifdef CONFIG_6xx
        case PPC_OPROFILE_G4:
            model = &op_model_7450;
            break;
#endif
#if defined(CONFIG_FSL_EMB_PERFMON)
        case PPC_OPROFILE_FSL_EMB:
            model = &op_model_fsl_emb;
            break;
#endif
        default:
            return -ENODEV;
    }

    model->num_counters = cur_cpu_spec->num_pmcs;

    ops->cpu_type = cur_cpu_spec->oprofile_cpu_type;
    ops->create_files = op_powerpc_create_files;
    ops->setup = op_powerpc_setup;
    ops->shutdown = op_powerpc_shutdown;
    ops->start = op_powerpc_start;
    ops->stop = op_powerpc_stop;
    ops->backtrace = op_powerpc_backtrace;

    printk(KERN_DEBUG "oprofile: using %s performance monitoring.\n",
           ops->cpu_type);

    return 0;
}

void oprofile_arch_exit(void)
{
}