linux/arch/sparc/oprofile/init.c
David S. Miller 63ef34827c sparc64: Provide oprofile pseudo-NMI on Niagara.
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-04 09:17:10 -08:00

251 lines
4.8 KiB
C

/**
* @file init.c
*
* @remark Copyright 2002 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon <levon@movementarian.org>
*/
#include <linux/kernel.h>
#include <linux/oprofile.h>
#include <linux/errno.h>
#include <linux/init.h>
#ifdef CONFIG_SPARC64
#include <asm/hypervisor.h>
#include <asm/spitfire.h>
#include <asm/cpudata.h>
#include <asm/irq.h>
static int nmi_enabled;
struct pcr_ops {
u64 (*read)(void);
void (*write)(u64);
};
static const struct pcr_ops *pcr_ops;
static u64 direct_pcr_read(void)
{
u64 val;
read_pcr(val);
return val;
}
static void direct_pcr_write(u64 val)
{
write_pcr(val);
}
static const struct pcr_ops direct_pcr_ops = {
.read = direct_pcr_read,
.write = direct_pcr_write,
};
static void n2_pcr_write(u64 val)
{
unsigned long ret;
ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val);
if (val != HV_EOK)
write_pcr(val);
}
static const struct pcr_ops n2_pcr_ops = {
.read = direct_pcr_read,
.write = n2_pcr_write,
};
/* In order to commonize as much of the implementation as
* possible, we use PICH as our counter. Mostly this is
* to accomodate Niagara-1 which can only count insn cycles
* in PICH.
*/
static u64 picl_value(void)
{
u32 delta = local_cpu_data().clock_tick / HZ;
return ((u64)((0 - delta) & 0xffffffff)) << 32;
}
#define PCR_PIC_PRIV 0x00000001 /* PIC access is privileged */
#define PCR_STRACE 0x00000002 /* Trace supervisor events */
#define PCR_UTRACE 0x00000004 /* Trace user events */
#define PCR_N2_HTRACE 0x00000008 /* Trace hypervisor events */
#define PCR_N2_TOE_OV0 0x00000010 /* Trap if PIC 0 overflows */
#define PCR_N2_TOE_OV1 0x00000020 /* Trap if PIC 1 overflows */
#define PCR_N2_MASK0 0x00003fc0
#define PCR_N2_MASK0_SHIFT 6
#define PCR_N2_SL0 0x0003c000
#define PCR_N2_SL0_SHIFT 14
#define PCR_N2_OV0 0x00040000
#define PCR_N2_MASK1 0x07f80000
#define PCR_N2_MASK1_SHIFT 19
#define PCR_N2_SL1 0x78000000
#define PCR_N2_SL1_SHIFT 27
#define PCR_N2_OV1 0x80000000
#define PCR_SUN4U_ENABLE (PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE)
#define PCR_N2_ENABLE (PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE | \
PCR_N2_TOE_OV1 | \
(2 << PCR_N2_SL1_SHIFT) | \
(0xff << PCR_N2_MASK1_SHIFT))
static u64 pcr_enable = PCR_SUN4U_ENABLE;
static void nmi_handler(struct pt_regs *regs)
{
pcr_ops->write(PCR_PIC_PRIV);
if (nmi_enabled) {
oprofile_add_sample(regs, 0);
write_pic(picl_value());
pcr_ops->write(pcr_enable);
}
}
/* We count "clock cycle" events in the lower 32-bit PIC.
* Then configure it such that it overflows every HZ, and thus
* generates a level 15 interrupt at that frequency.
*/
static void cpu_nmi_start(void *_unused)
{
pcr_ops->write(PCR_PIC_PRIV);
write_pic(picl_value());
pcr_ops->write(pcr_enable);
}
static void cpu_nmi_stop(void *_unused)
{
pcr_ops->write(PCR_PIC_PRIV);
}
static int nmi_start(void)
{
int err = register_perfctr_intr(nmi_handler);
if (!err) {
nmi_enabled = 1;
wmb();
err = on_each_cpu(cpu_nmi_start, NULL, 1);
if (err) {
nmi_enabled = 0;
wmb();
on_each_cpu(cpu_nmi_stop, NULL, 1);
release_perfctr_intr(nmi_handler);
}
}
return err;
}
static void nmi_stop(void)
{
nmi_enabled = 0;
wmb();
on_each_cpu(cpu_nmi_stop, NULL, 1);
release_perfctr_intr(nmi_handler);
synchronize_sched();
}
static unsigned long perf_hsvc_group;
static unsigned long perf_hsvc_major;
static unsigned long perf_hsvc_minor;
static int __init register_perf_hsvc(void)
{
if (tlb_type == hypervisor) {
switch (sun4v_chip_type) {
case SUN4V_CHIP_NIAGARA1:
perf_hsvc_group = HV_GRP_NIAG_PERF;
break;
case SUN4V_CHIP_NIAGARA2:
perf_hsvc_group = HV_GRP_N2_CPU;
break;
default:
return -ENODEV;
}
perf_hsvc_major = 1;
perf_hsvc_minor = 0;
if (sun4v_hvapi_register(perf_hsvc_group,
perf_hsvc_major,
&perf_hsvc_minor)) {
printk("perfmon: Could not register N2 hvapi.\n");
return -ENODEV;
}
}
return 0;
}
static void unregister_perf_hsvc(void)
{
if (tlb_type != hypervisor)
return;
sun4v_hvapi_unregister(perf_hsvc_group);
}
static int oprofile_nmi_init(struct oprofile_operations *ops)
{
int err = register_perf_hsvc();
if (err)
return err;
switch (tlb_type) {
case hypervisor:
pcr_ops = &n2_pcr_ops;
pcr_enable = PCR_N2_ENABLE;
break;
case cheetah:
case cheetah_plus:
pcr_ops = &direct_pcr_ops;
break;
default:
return -ENODEV;
}
ops->create_files = NULL;
ops->setup = NULL;
ops->shutdown = NULL;
ops->start = nmi_start;
ops->stop = nmi_stop;
ops->cpu_type = "timer";
printk(KERN_INFO "oprofile: Using perfctr based NMI timer interrupt.\n");
return 0;
}
#endif
int __init oprofile_arch_init(struct oprofile_operations *ops)
{
int ret = -ENODEV;
#ifdef CONFIG_SPARC64
ret = oprofile_nmi_init(ops);
if (!ret)
return ret;
#endif
return ret;
}
void oprofile_arch_exit(void)
{
#ifdef CONFIG_SPARC64
unregister_perf_hsvc();
#endif
}