/*
* Cell Broadband Engine OProfile Support
*
* (C) Copyright IBM Corporation 2006
*
* Author: David Erb (djerb@us.ibm.com)
* Modifications:
* Carl Love <carll@us.ibm.com>
* Maynard Johnson <maynardj@us.ibm.com>
*
* 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/cpufreq.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/kthread.h>
#include <linux/oprofile.h>
#include <linux/percpu.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <asm/cell-pmu.h>
#include <asm/cputable.h>
#include <asm/firmware.h>
#include <asm/io.h>
#include <asm/oprofile_impl.h>
#include <asm/processor.h>
#include <asm/prom.h>
#include <asm/ptrace.h>
#include <asm/reg.h>
#include <asm/rtas.h>
#include <asm/system.h>
#include "../platforms/cell/interrupt.h"
#define PPU_CYCLES_EVENT_NUM 1 /* event number for CYCLES */
#define PPU_CYCLES_GRP_NUM 1 /* special group number for identifying
* PPU_CYCLES event
*/
#define CBE_COUNT_ALL_CYCLES 0x42800000 /* PPU cycle event specifier */
#define NUM_THREADS 2 /* number of physical threads in
* physical processor
*/
#define NUM_TRACE_BUS_WORDS 4
#define NUM_INPUT_BUS_WORDS 2
struct pmc_cntrl_data {
unsigned long vcntr;
unsigned long evnts;
unsigned long masks;
unsigned long enabled;
};
/*
* ibm,cbe-perftools rtas parameters
*/
struct pm_signal {
u16 cpu; /* Processor to modify */
u16 sub_unit; /* hw subunit this applies to (if applicable) */
short int signal_group; /* Signal Group to Enable/Disable */
u8 bus_word; /* Enable/Disable on this Trace/Trigger/Event
* Bus Word(s) (bitmask)
*/
u8 bit; /* Trigger/Event bit (if applicable) */
};
/*
* rtas call arguments
*/
enum {
SUBFUNC_RESET = 1,
SUBFUNC_ACTIVATE = 2,
SUBFUNC_DEACTIVATE = 3,
PASSTHRU_IGNORE = 0,
PASSTHRU_ENABLE = 1,
PASSTHRU_DISABLE = 2,
};
struct pm_cntrl {
u16 enable;
u16 stop_at_max;
u16 trace_mode;
u16 freeze;
u16 count_mode;
};
static struct {
u32 group_control;
u32 debug_bus_control;
struct pm_cntrl pm_cntrl;
u32 pm07_cntrl[NR_PHYS_CTRS];
} pm_regs;
#define GET_SUB_UNIT(x) ((x & 0x0000f000) >> 12)
#define GET_BUS_WORD(x) ((x & 0x000000f0) >> 4)
#define GET_BUS_TYPE(x) ((x & 0x00000300) >> 8)
#define GET_POLARITY(x) ((x & 0x00000002) >> 1)
#define GET_COUNT_CYCLES(x) (x & 0x00000001)
#define GET_INPUT_CONTROL(x) ((x & 0x00000004) >> 2)
static DEFINE_PER_CPU(unsigned long[NR_PHYS_CTRS], pmc_values);
static struct pmc_cntrl_data pmc_cntrl[NUM_THREADS][NR_PHYS_CTRS];
/* Interpetation of hdw_thread:
* 0 - even virtual cpus 0, 2, 4,...
* 1 - odd virtual cpus 1, 3, 5, ...
*/
static u32 hdw_thread;
static u32 virt_cntr_inter_mask;
static struct timer_list timer_virt_cntr;
/* pm_signal needs to be global since it is initialized in
* cell_reg_setup at the time when the necessary information
* is available.
*/
static struct pm_signal pm_signal[NR_PHYS_CTRS];
static int pm_rtas_token;
static u32 reset_value[NR_PHYS_CTRS];
static int num_counters;
static int oprofile_running;
static spinlock_t virt_cntr_lock = SPIN_LOCK_UNLOCKED;
static u32 ctr_enabled;
static unsigned char trace_bus[NUM_TRACE_BUS_WORDS];
static unsigned char input_bus[NUM_INPUT_BUS_WORDS];
/*
* Firmware interface functions
*/
static int
rtas_ibm_cbe_perftools(int subfunc, int passthru,
void *address, unsigned long length)
{
u64 paddr = __pa(address);
return rtas_call(pm_rtas_token, 5, 1, NULL, subfunc, passthru,
paddr >> 32, paddr & 0xffffffff, length);
}
static void pm_rtas_reset_signals(u32 node)
{
int ret;
struct pm_signal pm_signal_local;
/* The debug bus is being set to the passthru disable state.
* However, the FW still expects atleast one legal signal routing
* entry or it will return an error on the arguments. If we don't
* supply a valid entry, we must ignore all return values. Ignoring
* all return values means we might miss an error we should be
* concerned about.
*/
/* fw expects physical cpu #. */
pm_signal_local.cpu = node;
pm_signal_local.signal_group = 21;
pm_signal_local.bus_word = 1;
pm_signal_local.sub_unit = 0;
pm_signal_local.bit = 0;
ret = rtas_ibm_cbe_perftools(SUBFUNC_RESET, PASSTHRU_DISABLE,
&pm_signal_local,
sizeof(struct pm_signal));
if (ret)
printk(KERN_WARNING "%s: rtas returned: %d\n",
__FUNCTION__, ret);
}
static void pm_rtas_activate_signals(u32 node, u32 count)
{
int ret;
int i, j;
struct pm_signal pm_signal_local[NR_PHYS_CTRS];
/* There is no debug setup required for the cycles event.
* Note that only events in the same group can be used.
* Otherwise, there will be conflicts in correctly routing
* the signals on the debug bus. It is the responsiblity
* of the OProfile user tool to check the events are in
* the same group.
*/
i = 0;
for (j = 0; j < count; j++) {
if (pm_signal[j].signal_group != PPU_CYCLES_GRP_NUM) {
/* fw expects physical cpu # */
pm_signal_local[i].cpu = node;
pm_signal_local[i].signal_group
= pm_signal[j].signal_group;
pm_signal_local[i].bus_word = pm_signal[j].bus_word;
pm_signal_local[i].sub_unit = pm_signal[j].sub_unit;
pm_signal_local[i].bit = pm_signal[j].bit;
i++;
}
}
if (i != 0) {
ret = rtas_ibm_cbe_perftools(SUBFUNC_ACTIVATE, PASSTHRU_ENABLE,
pm_signal_local,
i * sizeof(struct pm_signal));
if (ret)
printk(KERN_WARNING "%s: rtas returned: %d\n",
__FUNCTION__, ret);
}
}
/*
* PM Signal functions
*/
static void set_pm_event(u32 ctr, int event, u32 unit_mask)
{
struct pm_signal *p;
u32 signal_bit;
u32 bus_word, bus_type, count_cycles, polarity, input_control;
int j, i;
if (event == PPU_CYCLES_EVENT_NUM) {
/* Special Event: Count all cpu cycles */
pm_regs.pm07_cntrl[ctr] = CBE_COUNT_ALL_CYCLES;
p = &(pm_signal[ctr]);
p->signal_group = PPU_CYCLES_GRP_NUM;
p->bus_word = 1;
p->sub_unit = 0;
p->bit = 0;
goto out;
} else {
pm_regs.pm07_cntrl[ctr] = 0;
}
bus_word = GET_BUS_WORD(unit_mask);
bus_type = GET_BUS_TYPE(unit_mask);
count_cycles = GET_COUNT_CYCLES(unit_mask);
polarity = GET_POLARITY(unit_mask);
input_control = GET_INPUT_CONTROL(unit_mask);
signal_bit = (event % 100);
p = &(pm_signal[ctr]);
p->signal_group = event / 100;
p->bus_word = bus_word;
p->sub_unit = (unit_mask & 0x0000f000) >> 12;
pm_regs.pm07_cntrl[ctr] = 0;
pm_regs.pm07_cntrl[ctr] |= PM07_CTR_COUNT_CYCLES(count_cycles);
pm_regs.pm07_cntrl[ctr] |= PM07_CTR_POLARITY(polarity);
pm_regs.pm07_cntrl[ctr] |= PM07_CTR_INPUT_CONTROL(input_control);
/* Some of the islands signal selection is based on 64 bit words.
* The debug bus words are 32 bits, the input words to the performance
* counters are defined as 32 bits. Need to convert the 64 bit island
* specification to the appropriate 32 input bit and bus word for the
* performance counter event selection. See the CELL Performance
* monitoring signals manual and the Perf cntr hardware descriptions
* for the details.
*/
if (input_control == 0) {
if (signal_bit > 31) {
signal_bit -= 32;
if (bus_word == 0x3)
bus_word = 0x2;
else if (bus_word == 0xc)
bus_word = 0x8;
}
if ((bus_type == 0) && p->signal_group >= 60)
bus_type = 2;
if ((bus_type == 1) && p->signal_group >= 50)
bus_type = 0;
pm_regs.pm07_cntrl[ctr] |= PM07_CTR_INPUT_MUX(signal_bit);
} else {
pm_regs.pm07_cntrl[ctr] = 0;
p->bit = signal_bit;
}
for (i = 0; i < NUM_TRACE_BUS_WORDS; i++) {
if (bus_word & (1 << i)) {
pm_regs.debug_bus_control |=
(bus_type << (31 - (2 * i) + 1));
for (j = 0; j < NUM_INPUT_BUS_WORDS; j++) {
if (input_bus[j] == 0xff) {
input_bus[j] = i;
pm_regs.group_control |=
(i << (31 - i));
break;
}
}
}
}
out:
;
}
static void write_pm_cntrl(int cpu)
{
/* Oprofile will use 32 bit counters, set bits 7:10 to 0
* pmregs.pm_cntrl is a global
*/
u32 val = 0;
if (pm_regs.pm_cntrl.enable == 1)
val |= CBE_PM_ENABLE_PERF_MON;
if (pm_regs.pm_cntrl.stop_at_max == 1)
val |= CBE_PM_STOP_AT_MAX;
if (pm_regs.pm_cntrl.trace_mode == 1)
val |= CBE_PM_TRACE_MODE_SET(pm_regs.pm_cntrl.trace_mode);
if (pm_regs.pm_cntrl.freeze == 1)
val |= CBE_PM_FREEZE_ALL_CTRS;
/* Routine set_count_mode must be called previously to set
* the count mode based on the user selection of user and kernel.
*/
val |= CBE_PM_COUNT_MODE_SET(pm_regs.pm_cntrl.count_mode);
cbe_write_pm(cpu, pm_control, val);
}
static inline void
set_count_mode(u32 kernel, u32 user)
{
/* The user must specify user and kernel if they want them. If
* neither is specified, OProfile will count in hypervisor mode.
* pm_regs.pm_cntrl is a global
*/
if (kernel) {
if (user)
pm_regs.pm_cntrl.count_mode = CBE_COUNT_ALL_MODES;
else
pm_regs.pm_cntrl.count_mode =
CBE_COUNT_SUPERVISOR_MODE;
} else {
if (user)
pm_regs.pm_cntrl.count_mode = CBE_COUNT_PROBLEM_MODE;
else
pm_regs.pm_cntrl.count_mode =
CBE_COUNT_HYPERVISOR_MODE;
}
}
static inline void enable_ctr(u32 cpu, u32 ctr, u32 * pm07_cntrl)
{
pm07_cntrl[ctr] |= CBE_PM_CTR_ENABLE;
cbe_write_pm07_control(cpu, ctr, pm07_cntrl[ctr]);
}
/*
* Oprofile is expected to collect data on all CPUs simultaneously.
* However, there is one set of performance counters per node. There are
* two hardware threads or virtual CPUs on each node. Hence, OProfile must
* multiplex in time the performance counter collection on the two virtual
* CPUs. The multiplexing of the performance counters is done by this
* virtual counter routine.
*
* The pmc_values used below is defined as 'per-cpu' but its use is
* more akin to 'per-node'. We need to store two sets of counter
* values per node -- one for the previous run and one for the next.
* The per-cpu[NR_PHYS_CTRS] gives us the storage we need. Each odd/even
* pair of per-cpu arrays is used for storing the previous and next
* pmc values for a given node.
* NOTE: We use the per-cpu variable to improve cache performance.
*/
static void cell_virtual_cntr(unsigned long data)
{
/* This routine will alternate loading the virtual counters for
* virtual CPUs
*/
int i, prev_hdw_thread, next_hdw_thread;
u32 cpu;
unsigned long flags;
/* Make sure that the interrupt_hander and
* the virt counter are not both playing with
* the counters on the same node.
*/
spin_lock_irqsave(&virt_cntr_lock, flags);
prev_hdw_thread = hdw_thread;
/* switch the cpu handling the interrupts */
hdw_thread = 1 ^ hdw_thread;
next_hdw_thread = hdw_thread;
for (i = 0; i < num_counters; i++)
/* There are some per thread events. Must do the
* set event, for the thread that is being started
*/
set_pm_event(i,
pmc_cntrl[next_hdw_thread][i].evnts,
pmc_cntrl[next_hdw_thread][i].masks);
/* The following is done only once per each node, but
* we need cpu #, not node #, to pass to the cbe_xxx functions.
*/
for_each_online_cpu(cpu) {
if (cbe_get_hw_thread_id(cpu))
continue;
/* stop counters, save counter values, restore counts
* for previous thread
*/
cbe_disable_pm(cpu);
cbe_disable_pm_interrupts(cpu);
for (i = 0; i < num_counters; i++) {
per_cpu(pmc_values, cpu + prev_hdw_thread)[i]
= cbe_read_ctr(cpu, i);
if (per_cpu(pmc_values, cpu + next_hdw_thread)[i]
== 0xFFFFFFFF)
/* If the cntr value is 0xffffffff, we must
* reset that to 0xfffffff0 when the current
* thread is restarted. This will generate a
* new interrupt and make sure that we never
* restore the counters to the max value. If
* the counters were restored to the max value,
* they do not increment and no interrupts are
* generated. Hence no more samples will be
* collected on that cpu.
*/
cbe_write_ctr(cpu, i, 0xFFFFFFF0);
else
cbe_write_ctr(cpu, i,
per_cpu(pmc_values,
cpu +
next_hdw_thread)[i]);
}
/* Switch to the other thread. Change the interrupt
* and control regs to be scheduled on the CPU
* corresponding to the thread to execute.
*/
for (i = 0; i < num_counters; i++) {
if (pmc_cntrl[next_hdw_thread][i].enabled) {
/* There are some per thread events.
* Must do the set event, enable_cntr
* for each cpu.
*/
enable_ctr(cpu, i,
pm_regs.pm07_cntrl);
} else {
cbe_write_pm07_control(cpu, i, 0);
}
}
/* Enable interrupts on the CPU thread that is starting */
cbe_enable_pm_interrupts(cpu, next_hdw_thread,
virt_cntr_inter_mask);
cbe_enable_pm(cpu);
}
spin_unlock_irqrestore(&virt_cntr_lock, flags);
mod_timer(&timer_virt_cntr, jiffies + HZ / 10);
}
static void start_virt_cntrs(void)
{
init_timer(&timer_virt_cntr);
timer_virt_cntr.function = cell_virtual_cntr;
timer_virt_cntr.data = 0UL;
timer_virt_cntr.expires = jiffies + HZ / 10;
add_timer(&timer_virt_cntr);
}
/* This function is called once for all cpus combined */
static void
cell_reg_setup(struct op_counter_config *ctr,
struct op_system_config *sys, int num_ctrs)
{
int i, j, cpu;
pm_rtas_token = rtas_token("ibm,cbe-perftools");
if (pm_rtas_token == RTAS_UNKNOWN_SERVICE) {
printk(KERN_WARNING "%s: RTAS_UNKNOWN_SERVICE\n",
__FUNCTION__);
goto out;
}
num_counters = num_ctrs;
pm_regs.group_control = 0;
pm_regs.debug_bus_control = 0;
/* setup the pm_control register */
memset(&pm_regs.pm_cntrl, 0, sizeof(struct pm_cntrl));
pm_regs.pm_cntrl.stop_at_max = 1;
pm_regs.pm_cntrl.trace_mode = 0;
pm_regs.pm_cntrl.freeze = 1;
set_count_mode(sys->enable_kernel, sys->enable_user);
/* Setup the thread 0 events */
for (i = 0; i < num_ctrs; ++i) {
pmc_cntrl[0][i].evnts = ctr[i].event;
pmc_cntrl[0][i].masks = ctr[i].unit_mask;
pmc_cntrl[0][i].enabled = ctr[i].enabled;
pmc_cntrl[0][i].vcntr = i;
for_each_possible_cpu(j)
per_cpu(pmc_values, j)[i] = 0;
}
/* Setup the thread 1 events, map the thread 0 event to the
* equivalent thread 1 event.
*/
for (i = 0; i < num_ctrs; ++i) {
if ((ctr[i].event >= 2100) && (ctr[i].event <= 2111))
pmc_cntrl[1][i].evnts = ctr[i].event + 19;
else if (ctr[i].event == 2203)
pmc_cntrl[1][i].evnts = ctr[i].event;
else if ((ctr[i].event >= 2200) && (ctr[i].event <= 2215))
pmc_cntrl[1][i].evnts = ctr[i].event + 16;
else
pmc_cntrl[1][i].evnts = ctr[i].event;
pmc_cntrl[1][i].masks = ctr[i].unit_mask;
pmc_cntrl[1][i].enabled = ctr[i].enabled;
pmc_cntrl[1][i].vcntr = i;
}
for (i = 0; i < NUM_TRACE_BUS_WORDS; i++)
trace_bus[i] = 0xff;
for (i = 0; i < NUM_INPUT_BUS_WORDS; i++)
input_bus[i] = 0xff;
/* Our counters count up, and "count" refers to
* how much before the next interrupt, and we interrupt
* on overflow. So we calculate the starting value
* which will give us "count" until overflow.
* Then we set the events on the enabled counters.
*/
for (i = 0; i < num_counters; ++i) {
/* start with virtual counter set 0 */
if (pmc_cntrl[0][i].enabled) {
/* Using 32bit counters, reset max - count */
reset_value[i] = 0xFFFFFFFF - ctr[i].count;
set_pm_event(i,
pmc_cntrl[0][i].evnts,
pmc_cntrl[0][i].masks);
/* global, used by cell_cpu_setup */
ctr_enabled |= (1 << i);
}
}
/* initialize the previous counts for the virtual cntrs */
for_each_online_cpu(cpu)
for (i = 0; i < num_counters; ++i) {
per_cpu(pmc_values, cpu)[i] = reset_value[i];
}
out:
;
}
/* This function is called once for each cpu */
static void cell_cpu_setup(struct op_counter_config *cntr)
{
u32 cpu = smp_processor_id();
u32 num_enabled = 0;
int i;
/* There is one performance monitor per processor chip (i.e. node),
* so we only need to perform this function once per node.
*/
if (cbe_get_hw_thread_id(cpu))
goto out;
if (pm_rtas_token == RTAS_UNKNOWN_SERVICE) {
printk(KERN_WARNING "%s: RTAS_UNKNOWN_SERVICE\n",
__FUNCTION__);
goto out;
}
/* Stop all counters */
cbe_disable_pm(cpu);
cbe_disable_pm_interrupts(cpu);
cbe_write_pm(cpu, pm_interval, 0);
cbe_write_pm(cpu, pm_start_stop, 0);
cbe_write_pm(cpu, group_control, pm_regs.group_control);
cbe_write_pm(cpu, debug_bus_control, pm_regs.debug_bus_control);
write_pm_cntrl(cpu);
for (i = 0; i < num_counters; ++i) {
if (ctr_enabled & (1 << i)) {
pm_signal[num_enabled].cpu = cbe_cpu_to_node(cpu);
num_enabled++;
}
}
pm_rtas_activate_signals(cbe_cpu_to_node(cpu), num_enabled);
out:
;
}
static void cell_global_start(struct op_counter_config *ctr)
{
u32 cpu;
u32 interrupt_mask = 0;
u32 i;
/* This routine gets called once for the system.
* There is one performance monitor per node, so we
* only need to perform this function once per node.
*/
for_each_online_cpu(cpu) {
if (cbe_get_hw_thread_id(cpu))
continue;
interrupt_mask = 0;
for (i = 0; i < num_counters; ++i) {
if (ctr_enabled & (1 << i)) {
cbe_write_ctr(cpu, i, reset_value[i]);
enable_ctr(cpu, i, pm_regs.pm07_cntrl);
interrupt_mask |=
CBE_PM_CTR_OVERFLOW_INTR(i);
} else {
/* Disable counter */
cbe_write_pm07_control(cpu, i, 0);
}
}
cbe_get_and_clear_pm_interrupts(cpu);
cbe_enable_pm_interrupts(cpu, hdw_thread, interrupt_mask);
cbe_enable_pm(cpu);
}
virt_cntr_inter_mask = interrupt_mask;
oprofile_running = 1;
smp_wmb();
/* NOTE: start_virt_cntrs will result in cell_virtual_cntr() being
* executed which manipulates the PMU. We start the "virtual counter"
* here so that we do not need to synchronize access to the PMU in
* the above for-loop.
*/
start_virt_cntrs();
}
static void cell_global_stop(void)
{
int cpu;
/* This routine will be called once for the system.
* There is one performance monitor per node, so we
* only need to perform this function once per node.
*/
del_timer_sync(&timer_virt_cntr);
oprofile_running = 0;
smp_wmb();
for_each_online_cpu(cpu) {
if (cbe_get_hw_thread_id(cpu))
continue;
cbe_sync_irq(cbe_cpu_to_node(cpu));
/* Stop the counters */
cbe_disable_pm(cpu);
/* Deactivate the signals */
pm_rtas_reset_signals(cbe_cpu_to_node(cpu));
/* Deactivate interrupts */
cbe_disable_pm_interrupts(cpu);
}
}
static void
cell_handle_interrupt(struct pt_regs *regs, struct op_counter_config *ctr)
{
u32 cpu;
u64 pc;
int is_kernel;
unsigned long flags = 0;
u32 interrupt_mask;
int i;
cpu = smp_processor_id();
/* Need to make sure the interrupt handler and the virt counter
* routine are not running at the same time. See the
* cell_virtual_cntr() routine for additional comments.
*/
spin_lock_irqsave(&virt_cntr_lock, flags);
/* Need to disable and reenable the performance counters
* to get the desired behavior from the hardware. This
* is hardware specific.
*/
cbe_disable_pm(cpu);
interrupt_mask = cbe_get_and_clear_pm_interrupts(cpu);
/* If the interrupt mask has been cleared, then the virt cntr
* has cleared the interrupt. When the thread that generated
* the interrupt is restored, the data count will be restored to
* 0xffffff0 to cause the interrupt to be regenerated.
*/
if ((oprofile_running == 1) && (interrupt_mask != 0)) {
pc = regs->nip;
is_kernel = is_kernel_addr(pc);
for (i = 0; i < num_counters; ++i) {
if ((interrupt_mask & CBE_PM_CTR_OVERFLOW_INTR(i))
&& ctr[i].enabled) {
oprofile_add_pc(pc, is_kernel, i);
cbe_write_ctr(cpu, i, reset_value[i]);
}
}
/* The counters were frozen by the interrupt.
* Reenable the interrupt and restart the counters.
* If there was a race between the interrupt handler and
* the virtual counter routine. The virutal counter
* routine may have cleared the interrupts. Hence must
* use the virt_cntr_inter_mask to re-enable the interrupts.
*/
cbe_enable_pm_interrupts(cpu, hdw_thread,
virt_cntr_inter_mask);
/* The writes to the various performance counters only writes
* to a latch. The new values (interrupt setting bits, reset
* counter value etc.) are not copied to the actual registers
* until the performance monitor is enabled. In order to get
* this to work as desired, the permormance monitor needs to
* be disabled while writting to the latches. This is a
* HW design issue.
*/
cbe_enable_pm(cpu);
}
spin_unlock_irqrestore(&virt_cntr_lock, flags);
}
struct op_powerpc_model op_model_cell = {
.reg_setup = cell_reg_setup,
.cpu_setup = cell_cpu_setup,
.global_start = cell_global_start,
.global_stop = cell_global_stop,
.handle_interrupt = cell_handle_interrupt,
};
