/*
* Copyright (C) 2004 Anton Blanchard <anton@au.ibm.com>, IBM
*
* 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 <asm/ptrace.h>
#include <asm/system.h>
#include <asm/processor.h>
#include <asm/cputable.h>
#include <asm/systemcfg.h>
#include <asm/rtas.h>
#define dbg(args...)
#include "op_impl.h"
static unsigned long reset_value[OP_MAX_COUNTER];
static int num_counters;
static int oprofile_running;
static int mmcra_has_sihv;
/* mmcr values are set in power4_reg_setup, used in power4_cpu_setup */
static u32 mmcr0_val;
static u64 mmcr1_val;
static u32 mmcra_val;
/*
* Since we do not have an NMI, backtracing through spinlocks is
* only a best guess. In light of this, allow it to be disabled at
* runtime.
*/
static int backtrace_spinlocks;
static void power4_reg_setup(struct op_counter_config *ctr,
struct op_system_config *sys,
int num_ctrs)
{
int i;
num_counters = num_ctrs;
/*
* SIHV / SIPR bits are only implemented on POWER4+ (GQ) and above.
* However we disable it on all POWER4 until we verify it works
* (I was seeing some strange behaviour last time I tried).
*
* It has been verified to work on POWER5 so we enable it there.
*/
if (cpu_has_feature(CPU_FTR_MMCRA_SIHV))
mmcra_has_sihv = 1;
/*
* The performance counter event settings are given in the mmcr0,
* mmcr1 and mmcra values passed from the user in the
* op_system_config structure (sys variable).
*/
mmcr0_val = sys->mmcr0;
mmcr1_val = sys->mmcr1;
mmcra_val = sys->mmcra;
backtrace_spinlocks = sys->backtrace_spinlocks;
for (i = 0; i < num_counters; ++i)
reset_value[i] = 0x80000000UL - ctr[i].count;
/* setup user and kernel profiling */
if (sys->enable_kernel)
mmcr0_val &= ~MMCR0_KERNEL_DISABLE;
else
mmcr0_val |= MMCR0_KERNEL_DISABLE;
if (sys->enable_user)
mmcr0_val &= ~MMCR0_PROBLEM_DISABLE;
else
mmcr0_val |= MMCR0_PROBLEM_DISABLE;
}
extern void ppc64_enable_pmcs(void);
static void power4_cpu_setup(void *unused)
{
unsigned int mmcr0 = mmcr0_val;
unsigned long mmcra = mmcra_val;
ppc64_enable_pmcs();
/* set the freeze bit */
mmcr0 |= MMCR0_FC;
mtspr(SPRN_MMCR0, mmcr0);
mmcr0 |= MMCR0_FCM1|MMCR0_PMXE|MMCR0_FCECE;
mmcr0 |= MMCR0_PMC1CE|MMCR0_PMCjCE;
mtspr(SPRN_MMCR0, mmcr0);
mtspr(SPRN_MMCR1, mmcr1_val);
mmcra |= MMCRA_SAMPLE_ENABLE;
mtspr(SPRN_MMCRA, mmcra);
dbg("setup on cpu %d, mmcr0 %lx\n", smp_processor_id(),
mfspr(SPRN_MMCR0));
dbg("setup on cpu %d, mmcr1 %lx\n", smp_processor_id(),
mfspr(SPRN_MMCR1));
dbg("setup on cpu %d, mmcra %lx\n", smp_processor_id(),
mfspr(SPRN_MMCRA));
}
static void power4_start(struct op_counter_config *ctr)
{
int i;
unsigned int mmcr0;
/* set the PMM bit (see comment below) */
mtmsrd(mfmsr() | MSR_PMM);
for (i = 0; i < num_counters; ++i) {
if (ctr[i].enabled) {
ctr_write(i, reset_value[i]);
} else {
ctr_write(i, 0);
}
}
mmcr0 = mfspr(SPRN_MMCR0);
/*
* We must clear the PMAO bit on some (GQ) chips. Just do it
* all the time
*/
mmcr0 &= ~MMCR0_PMAO;
/*
* now clear the freeze bit, counting will not start until we
* rfid from this excetion, because only at that point will
* the PMM bit be cleared
*/
mmcr0 &= ~MMCR0_FC;
mtspr(SPRN_MMCR0, mmcr0);
oprofile_running = 1;
dbg("start on cpu %d, mmcr0 %x\n", smp_processor_id(), mmcr0);
}
static void power4_stop(void)
{
unsigned int mmcr0;
/* freeze counters */
mmcr0 = mfspr(SPRN_MMCR0);
mmcr0 |= MMCR0_FC;
mtspr(SPRN_MMCR0, mmcr0);
oprofile_running = 0;
dbg("stop on cpu %d, mmcr0 %x\n", smp_processor_id(), mmcr0);
mb();
}
/* Fake functions used by canonicalize_pc */
static void __attribute_used__ hypervisor_bucket(void)
{
}
static void __attribute_used__ rtas_bucket(void)
{
}
static void __attribute_used__ kernel_unknown_bucket(void)
{
}
static unsigned long check_spinlock_pc(struct pt_regs *regs,
unsigned long profile_pc)
{
unsigned long pc = instruction_pointer(regs);
/*
* If both the SIAR (sampled instruction) and the perfmon exception
* occurred in a spinlock region then we account the sample to the
* calling function. This isnt 100% correct, we really need soft
* IRQ disable so we always get the perfmon exception at the
* point at which the SIAR is set.
*/
if (backtrace_spinlocks && in_lock_functions(pc) &&
in_lock_functions(profile_pc))
return regs->link;
else
return profile_pc;
}
/*
* On GQ and newer the MMCRA stores the HV and PR bits at the time
* the SIAR was sampled. We use that to work out if the SIAR was sampled in
* the hypervisor, our exception vectors or RTAS.
*/
static unsigned long get_pc(struct pt_regs *regs)
{
unsigned long pc = mfspr(SPRN_SIAR);
unsigned long mmcra;
/* Cant do much about it */
if (!mmcra_has_sihv)
return check_spinlock_pc(regs, pc);
mmcra = mfspr(SPRN_MMCRA);
/* Were we in the hypervisor? */
if ((systemcfg->platform == PLATFORM_PSERIES_LPAR) &&
(mmcra & MMCRA_SIHV))
/* function descriptor madness */
return *((unsigned long *)hypervisor_bucket);
/* We were in userspace, nothing to do */
if (mmcra & MMCRA_SIPR)
return pc;
#ifdef CONFIG_PPC_RTAS
/* Were we in RTAS? */
if (pc >= rtas.base && pc < (rtas.base + rtas.size))
/* function descriptor madness */
return *((unsigned long *)rtas_bucket);
#endif
/* Were we in our exception vectors or SLB real mode miss handler? */
if (pc < 0x1000000UL)
return (unsigned long)__va(pc);
/* Not sure where we were */
if (pc < KERNELBASE)
/* function descriptor madness */
return *((unsigned long *)kernel_unknown_bucket);
return check_spinlock_pc(regs, pc);
}
static int get_kernel(unsigned long pc)
{
int is_kernel;
if (!mmcra_has_sihv) {
is_kernel = (pc >= KERNELBASE);
} else {
unsigned long mmcra = mfspr(SPRN_MMCRA);
is_kernel = ((mmcra & MMCRA_SIPR) == 0);
}
return is_kernel;
}
static void power4_handle_interrupt(struct pt_regs *regs,
struct op_counter_config *ctr)
{
unsigned long pc;
int is_kernel;
int val;
int i;
unsigned int mmcr0;
pc = get_pc(regs);
is_kernel = get_kernel(pc);
/* set the PMM bit (see comment below) */
mtmsrd(mfmsr() | MSR_PMM);
for (i = 0; i < num_counters; ++i) {
val = ctr_read(i);
if (val < 0) {
if (oprofile_running && ctr[i].enabled) {
oprofile_add_pc(pc, is_kernel, i);
ctr_write(i, reset_value[i]);
} else {
ctr_write(i, 0);
}
}
}
mmcr0 = mfspr(SPRN_MMCR0);
/* reset the perfmon trigger */
mmcr0 |= MMCR0_PMXE;
/*
* We must clear the PMAO bit on some (GQ) chips. Just do it
* all the time
*/
mmcr0 &= ~MMCR0_PMAO;
/*
* now clear the freeze bit, counting will not start until we
* rfid from this exception, because only at that point will
* the PMM bit be cleared
*/
mmcr0 &= ~MMCR0_FC;
mtspr(SPRN_MMCR0, mmcr0);
}
struct op_ppc64_model op_model_power4 = {
.reg_setup = power4_reg_setup,
.cpu_setup = power4_cpu_setup,
.start = power4_start,
.stop = power4_stop,
.handle_interrupt = power4_handle_interrupt,
};
