diff options
Diffstat (limited to 'arch/powerpc/oprofile/op_model_cell.c')
| -rw-r--r-- | arch/powerpc/oprofile/op_model_cell.c | 724 |
1 files changed, 724 insertions, 0 deletions
diff --git a/arch/powerpc/oprofile/op_model_cell.c b/arch/powerpc/oprofile/op_model_cell.c new file mode 100644 index 00000000000..2eb15f38810 --- /dev/null +++ b/arch/powerpc/oprofile/op_model_cell.c @@ -0,0 +1,724 @@ +/* + * 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 CBE_COUNT_ALL_CYCLES 0x42800000 /* PPU cycle event specifier */ + +#define NUM_THREADS 2 +#define VIRT_CNTR_SW_TIME_NS 100000000 // 0.5 seconds + +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) */ + u16 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[4]; +static unsigned char input_bus[2]; + +/* + * 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 j; + struct pm_signal pm_signal_local[NR_PHYS_CTRS]; + + for (j = 0; j < count; j++) { + /* fw expects physical cpu # */ + pm_signal_local[j].cpu = node; + pm_signal_local[j].signal_group = pm_signal[j].signal_group; + pm_signal_local[j].bus_word = pm_signal[j].bus_word; + pm_signal_local[j].sub_unit = pm_signal[j].sub_unit; + pm_signal_local[j].bit = pm_signal[j].bit; + } + + ret = rtas_ibm_cbe_perftools(SUBFUNC_ACTIVATE, PASSTHRU_ENABLE, + pm_signal_local, + count * 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 = 21; + 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; + + 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); + + 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 < 4; i++) { + if (bus_word & (1 << i)) { + pm_regs.debug_bus_control |= + (bus_type << (31 - (2 * i) + 1)); + + for (j = 0; j < 2; 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, struct pm_cntrl *pm_cntrl) +{ + /* Oprofile will use 32 bit counters, set bits 7:10 to 0 */ + u32 val = 0; + if (pm_cntrl->enable == 1) + val |= CBE_PM_ENABLE_PERF_MON; + + if (pm_cntrl->stop_at_max == 1) + val |= CBE_PM_STOP_AT_MAX; + + if (pm_cntrl->trace_mode == 1) + val |= CBE_PM_TRACE_MODE_SET(pm_cntrl->trace_mode); + + if (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_cntrl->count_mode); + cbe_write_pm(cpu, pm_control, val); +} + +static inline void +set_count_mode(u32 kernel, u32 user, struct pm_cntrl *pm_cntrl) +{ + /* The user must specify user and kernel if they want them. If + * neither is specified, OProfile will count in hypervisor mode + */ + if (kernel) { + if (user) + pm_cntrl->count_mode = CBE_COUNT_ALL_MODES; + else + pm_cntrl->count_mode = CBE_COUNT_SUPERVISOR_MODE; + } else { + if (user) + pm_cntrl->count_mode = CBE_COUNT_PROBLEM_MODE; + else + pm_cntrl->count_mode = CBE_COUNT_HYPERVISOR_MODE; + } +} + +static inline void enable_ctr(u32 cpu, u32 ctr, u32 * pm07_cntrl) +{ + + pm07_cntrl[ctr] |= PM07_CTR_ENABLE(1); + 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; + + /* 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. + */ + set_pm_event(i, + pmc_cntrl[next_hdw_thread][i].evnts, + pmc_cntrl[next_hdw_thread][i].masks); + 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, + &pm_regs.pm_cntrl); + + /* 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 < 4; i++) + trace_bus[i] = 0xff; + + for (i = 0; i < 2; 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, &pm_regs.pm_cntrl); + + 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_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_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, +}; |