[ARM] 5195/1: ARMv7 Oprofile support

Add Oprofile kernel support for ARMv7.
Tested on OMAP3430 and OMAP3530 chipsets (Cortex-A8).

Signed-off-by: Jean Pihet <jpihet@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

5 files changed, 520 insertions, 0 deletions

diff --git a/arch/arm/oprofile/Makefile b/arch/arm/oprofile/Makefile
index e61d0cc520b7..88e31f549f50 100644
--- a/arch/arm/oprofile/Makefile
+++ b/arch/arm/oprofile/Makefile
@@ -11,3 +11,4 @@ oprofile-$(CONFIG_CPU_XSCALE)		+= op_model_xscale.o
 oprofile-$(CONFIG_OPROFILE_ARM11_CORE)  += op_model_arm11_core.o
 oprofile-$(CONFIG_OPROFILE_ARMV6)       += op_model_v6.o
 oprofile-$(CONFIG_OPROFILE_MPCORE)      += op_model_mpcore.o
+oprofile-$(CONFIG_OPROFILE_ARMV7)       += op_model_v7.o
diff --git a/arch/arm/oprofile/common.c b/arch/arm/oprofile/common.c
index 0a5cf3a6438b..3fcd752d6146 100644
--- a/arch/arm/oprofile/common.c
+++ b/arch/arm/oprofile/common.c
@@ -145,6 +145,10 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
         spec = &op_mpcore_spec;
 #endif
 
+#ifdef CONFIG_OPROFILE_ARMV7
+        spec = &op_armv7_spec;
+#endif
+
         if (spec) {
                 ret = spec->init();
                 if (ret < 0)
diff --git a/arch/arm/oprofile/op_arm_model.h b/arch/arm/oprofile/op_arm_model.h
index 4899c629aa03..8c4e4f6a1de3 100644
--- a/arch/arm/oprofile/op_arm_model.h
+++ b/arch/arm/oprofile/op_arm_model.h
@@ -26,6 +26,7 @@ extern struct op_arm_model_spec op_xscale_spec;
 
 extern struct op_arm_model_spec op_armv6_spec;
 extern struct op_arm_model_spec op_mpcore_spec;
+extern struct op_arm_model_spec op_armv7_spec;
 
 extern void arm_backtrace(struct pt_regs * const regs, unsigned int depth);
 
diff --git a/arch/arm/oprofile/op_model_v7.c b/arch/arm/oprofile/op_model_v7.c
new file mode 100644
index 000000000000..f20295f14adb
--- /dev/null
+++ b/arch/arm/oprofile/op_model_v7.c
@@ -0,0 +1,411 @@
+/**
+ * op_model_v7.c
+ * ARM V7 (Cortex A8) Event Monitor Driver
+ *
+ * Copyright 2008 Jean Pihet <jpihet@mvista.com>
+ * Copyright 2004 ARM SMP Development Team
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/oprofile.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/smp.h>
+
+#include "op_counter.h"
+#include "op_arm_model.h"
+#include "op_model_v7.h"
+
+/* #define DEBUG */
+
+
+/*
+ * ARM V7 PMNC support
+ */
+
+static u32 cnt_en[CNTMAX];
+
+static inline void armv7_pmnc_write(u32 val)
+{
+        val &= PMNC_MASK;
+        asm volatile("mcr p15, 0, %0, c9, c12, 0" : : "r" (val));
+}
+
+static inline u32 armv7_pmnc_read(void)
+{
+        u32 val;
+
+        asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r" (val));
+        return val;
+}
+
+static inline u32 armv7_pmnc_enable_counter(unsigned int cnt)
+{
+        u32 val;
+
+        if (cnt >= CNTMAX) {
+                printk(KERN_ERR "oprofile: CPU%u enabling wrong PMNC counter"
+                        " %d\n", smp_processor_id(), cnt);
+                return -1;
+        }
+
+        if (cnt == CCNT)
+                val = CNTENS_C;
+        else
+                val = (1 << (cnt - CNT0));
+
+        val &= CNTENS_MASK;
+        asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (val));
+
+        return cnt;
+}
+
+static inline u32 armv7_pmnc_disable_counter(unsigned int cnt)
+{
+        u32 val;
+
+        if (cnt >= CNTMAX) {
+                printk(KERN_ERR "oprofile: CPU%u disabling wrong PMNC counter"
+                        " %d\n", smp_processor_id(), cnt);
+                return -1;
+        }
+
+        if (cnt == CCNT)
+                val = CNTENC_C;
+        else
+                val = (1 << (cnt - CNT0));
+
+        val &= CNTENC_MASK;
+        asm volatile("mcr p15, 0, %0, c9, c12, 2" : : "r" (val));
+
+        return cnt;
+}
+
+static inline u32 armv7_pmnc_enable_intens(unsigned int cnt)
+{
+        u32 val;
+
+        if (cnt >= CNTMAX) {
+                printk(KERN_ERR "oprofile: CPU%u enabling wrong PMNC counter"
+                        " interrupt enable %d\n", smp_processor_id(), cnt);
+                return -1;
+        }
+
+        if (cnt == CCNT)
+                val = INTENS_C;
+        else
+                val = (1 << (cnt - CNT0));
+
+        val &= INTENS_MASK;
+        asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (val));
+
+        return cnt;
+}
+
+static inline u32 armv7_pmnc_getreset_flags(void)
+{
+        u32 val;
+
+        /* Read */
+        asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
+
+        /* Write to clear flags */
+        val &= FLAG_MASK;
+        asm volatile("mcr p15, 0, %0, c9, c12, 3" : : "r" (val));
+
+        return val;
+}
+
+static inline int armv7_pmnc_select_counter(unsigned int cnt)
+{
+        u32 val;
+
+        if ((cnt == CCNT) || (cnt >= CNTMAX)) {
+                printk(KERN_ERR "oprofile: CPU%u selecting wrong PMNC counteri"
+                        " %d\n", smp_processor_id(), cnt);
+                return -1;
+        }
+
+        val = (cnt - CNT0) & SELECT_MASK;
+        asm volatile("mcr p15, 0, %0, c9, c12, 5" : : "r" (val));
+
+        return cnt;
+}
+
+static inline void armv7_pmnc_write_evtsel(unsigned int cnt, u32 val)
+{
+        if (armv7_pmnc_select_counter(cnt) == cnt) {
+                val &= EVTSEL_MASK;
+                asm volatile("mcr p15, 0, %0, c9, c13, 1" : : "r" (val));
+        }
+}
+
+static void armv7_pmnc_reset_counter(unsigned int cnt)
+{
+        u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), cnt);
+        u32 val = -(u32)counter_config[cpu_cnt].count;
+
+        switch (cnt) {
+        case CCNT:
+                armv7_pmnc_disable_counter(cnt);
+
+                asm volatile("mcr p15, 0, %0, c9, c13, 0" : : "r" (val));
+
+                if (cnt_en[cnt] != 0)
+                    armv7_pmnc_enable_counter(cnt);
+
+                break;
+
+        case CNT0:
+        case CNT1:
+        case CNT2:
+        case CNT3:
+                armv7_pmnc_disable_counter(cnt);
+
+                if (armv7_pmnc_select_counter(cnt) == cnt)
+                    asm volatile("mcr p15, 0, %0, c9, c13, 2" : : "r" (val));
+
+                if (cnt_en[cnt] != 0)
+                    armv7_pmnc_enable_counter(cnt);
+
+                break;
+
+        default:
+                printk(KERN_ERR "oprofile: CPU%u resetting wrong PMNC counter"
+                        " %d\n", smp_processor_id(), cnt);
+                break;
+        }
+}
+
+int armv7_setup_pmnc(void)
+{
+        unsigned int cnt;
+
+        if (armv7_pmnc_read() & PMNC_E) {
+                printk(KERN_ERR "oprofile: CPU%u PMNC still enabled when setup"
+                        " new event counter.\n", smp_processor_id());
+                return -EBUSY;
+        }
+
+        /*
+         * Initialize & Reset PMNC: C bit, D bit and P bit.
+         *  Note: Using a slower count for CCNT (D bit: divide by 64) results
+         *   in a more stable system
+         */
+        armv7_pmnc_write(PMNC_P | PMNC_C | PMNC_D);
+
+
+        for (cnt = CCNT; cnt < CNTMAX; cnt++) {
+                unsigned long event;
+                u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), cnt);
+
+                /*
+                 * Disable counter
+                 */
+                armv7_pmnc_disable_counter(cnt);
+                cnt_en[cnt] = 0;
+
+                if (!counter_config[cpu_cnt].enabled)
+                        continue;
+
+                event = counter_config[cpu_cnt].event & 255;
+
+                /*
+                 * Set event (if destined for PMNx counters)
+                 * We don't need to set the event if it's a cycle count
+                 */
+                if (cnt != CCNT)
+                        armv7_pmnc_write_evtsel(cnt, event);
+
+                /*
+                 * Enable interrupt for this counter
+                 */
+                armv7_pmnc_enable_intens(cnt);
+
+                /*
+                 * Reset counter
+                 */
+                armv7_pmnc_reset_counter(cnt);
+
+                /*
+                 * Enable counter
+                 */
+                armv7_pmnc_enable_counter(cnt);
+                cnt_en[cnt] = 1;
+        }
+
+        return 0;
+}
+
+static inline void armv7_start_pmnc(void)
+{
+        armv7_pmnc_write(armv7_pmnc_read() | PMNC_E);
+}
+
+static inline void armv7_stop_pmnc(void)
+{
+        armv7_pmnc_write(armv7_pmnc_read() & ~PMNC_E);
+}
+
+/*
+ * CPU counters' IRQ handler (one IRQ per CPU)
+ */
+static irqreturn_t armv7_pmnc_interrupt(int irq, void *arg)
+{
+        struct pt_regs *regs = get_irq_regs();
+        unsigned int cnt;
+        u32 flags;
+
+
+        /*
+         * Stop IRQ generation
+         */
+        armv7_stop_pmnc();
+
+        /*
+         * Get and reset overflow status flags
+         */
+        flags = armv7_pmnc_getreset_flags();
+
+        /*
+         * Cycle counter
+         */
+        if (flags & FLAG_C) {
+                u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), CCNT);
+                armv7_pmnc_reset_counter(CCNT);
+                oprofile_add_sample(regs, cpu_cnt);
+        }
+
+        /*
+         * PMNC counters 0:3
+         */
+        for (cnt = CNT0; cnt < CNTMAX; cnt++) {
+                if (flags & (1 << (cnt - CNT0))) {
+                        u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), cnt);
+                        armv7_pmnc_reset_counter(cnt);
+                        oprofile_add_sample(regs, cpu_cnt);
+                }
+        }
+
+        /*
+         * Allow IRQ generation
+         */
+        armv7_start_pmnc();
+
+        return IRQ_HANDLED;
+}
+
+int armv7_request_interrupts(int *irqs, int nr)
+{
+        unsigned int i;
+        int ret = 0;
+
+        for (i = 0; i < nr; i++) {
+                ret = request_irq(irqs[i], armv7_pmnc_interrupt,
+                                IRQF_DISABLED, "CP15 PMNC", NULL);
+                if (ret != 0) {
+                        printk(KERN_ERR "oprofile: unable to request IRQ%u"
+                                " for ARMv7\n",
+                               irqs[i]);
+                        break;
+                }
+        }
+
+        if (i != nr)
+                while (i-- != 0)
+                        free_irq(irqs[i], NULL);
+
+        return ret;
+}
+
+void armv7_release_interrupts(int *irqs, int nr)
+{
+        unsigned int i;
+
+        for (i = 0; i < nr; i++)
+                free_irq(irqs[i], NULL);
+}
+
+#ifdef DEBUG
+static void armv7_pmnc_dump_regs(void)
+{
+        u32 val;
+        unsigned int cnt;
+
+        printk(KERN_INFO "PMNC registers dump:\n");
+
+        asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r" (val));
+        printk(KERN_INFO "PMNC  =0x%08x\n", val);
+
+        asm volatile("mrc p15, 0, %0, c9, c12, 1" : "=r" (val));
+        printk(KERN_INFO "CNTENS=0x%08x\n", val);
+
+        asm volatile("mrc p15, 0, %0, c9, c14, 1" : "=r" (val));
+        printk(KERN_INFO "INTENS=0x%08x\n", val);
+
+        asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
+        printk(KERN_INFO "FLAGS =0x%08x\n", val);
+
+        asm volatile("mrc p15, 0, %0, c9, c12, 5" : "=r" (val));
+        printk(KERN_INFO "SELECT=0x%08x\n", val);
+
+        asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
+        printk(KERN_INFO "CCNT  =0x%08x\n", val);
+
+        for (cnt = CNT0; cnt < CNTMAX; cnt++) {
+                armv7_pmnc_select_counter(cnt);
+                asm volatile("mrc p15, 0, %0, c9, c13, 2" : "=r" (val));
+                printk(KERN_INFO "CNT[%d] count =0x%08x\n", cnt-CNT0, val);
+                asm volatile("mrc p15, 0, %0, c9, c13, 1" : "=r" (val));
+                printk(KERN_INFO "CNT[%d] evtsel=0x%08x\n", cnt-CNT0, val);
+        }
+}
+#endif
+
+
+static int irqs[] = {
+#ifdef CONFIG_ARCH_OMAP3
+        INT_34XX_BENCH_MPU_EMUL,
+#endif
+};
+
+static void armv7_pmnc_stop(void)
+{
+#ifdef DEBUG
+        armv7_pmnc_dump_regs();
+#endif
+        armv7_stop_pmnc();
+        armv7_release_interrupts(irqs, ARRAY_SIZE(irqs));
+}
+
+static int armv7_pmnc_start(void)
+{
+        int ret;
+
+#ifdef DEBUG
+        armv7_pmnc_dump_regs();
+#endif
+        ret = armv7_request_interrupts(irqs, ARRAY_SIZE(irqs));
+        if (ret >= 0)
+                armv7_start_pmnc();
+
+        return ret;
+}
+
+static int armv7_detect_pmnc(void)
+{
+        return 0;
+}
+
+struct op_arm_model_spec op_armv7_spec = {
+        .init           = armv7_detect_pmnc,
+        .num_counters   = 5,
+        .setup_ctrs     = armv7_setup_pmnc,
+        .start          = armv7_pmnc_start,
+        .stop           = armv7_pmnc_stop,
+        .name           = "arm/armv7",
+};
diff --git a/arch/arm/oprofile/op_model_v7.h b/arch/arm/oprofile/op_model_v7.h
new file mode 100644
index 000000000000..0e19bcc2e100
--- /dev/null
+++ b/arch/arm/oprofile/op_model_v7.h
@@ -0,0 +1,103 @@
+/**
+ * op_model_v7.h
+ * ARM v7 (Cortex A8) Event Monitor Driver
+ *
+ * Copyright 2008 Jean Pihet <jpihet@mvista.com>
+ * Copyright 2004 ARM SMP Development Team
+ * Copyright 2000-2004 Deepak Saxena <dsaxena@mvista.com>
+ * Copyright 2000-2004 MontaVista Software Inc
+ * Copyright 2004 Dave Jiang <dave.jiang@intel.com>
+ * Copyright 2004 Intel Corporation
+ * Copyright 2004 Zwane Mwaikambo <zwane@arm.linux.org.uk>
+ * Copyright 2004 Oprofile Authors
+ *
+ * Read the file COPYING
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef OP_MODEL_V7_H
+#define OP_MODEL_V7_H
+
+/*
+ * Per-CPU PMNC: config reg
+ */
+#define PMNC_E          (1 << 0)        /* Enable all counters */
+#define PMNC_P          (1 << 1)        /* Reset all counters */
+#define PMNC_C          (1 << 2)        /* Cycle counter reset */
+#define PMNC_D          (1 << 3)        /* CCNT counts every 64th cpu cycle */
+#define PMNC_X          (1 << 4)        /* Export to ETM */
+#define PMNC_DP         (1 << 5)        /* Disable CCNT if non-invasive debug*/
+#define PMNC_MASK       0x3f            /* Mask for writable bits */
+
+/*
+ * Available counters
+ */
+#define CCNT            0
+#define CNT0            1
+#define CNT1            2
+#define CNT2            3
+#define CNT3            4
+#define CNTMAX          5
+
+#define CPU_COUNTER(cpu, counter)       ((cpu) * CNTMAX + (counter))
+
+/*
+ * CNTENS: counters enable reg
+ */
+#define CNTENS_P0       (1 << 0)
+#define CNTENS_P1       (1 << 1)
+#define CNTENS_P2       (1 << 2)
+#define CNTENS_P3       (1 << 3)
+#define CNTENS_C        (1 << 31)
+#define CNTENS_MASK     0x8000000f      /* Mask for writable bits */
+
+/*
+ * CNTENC: counters disable reg
+ */
+#define CNTENC_P0       (1 << 0)
+#define CNTENC_P1       (1 << 1)
+#define CNTENC_P2       (1 << 2)
+#define CNTENC_P3       (1 << 3)
+#define CNTENC_C        (1 << 31)
+#define CNTENC_MASK     0x8000000f      /* Mask for writable bits */
+
+/*
+ * INTENS: counters overflow interrupt enable reg
+ */
+#define INTENS_P0       (1 << 0)
+#define INTENS_P1       (1 << 1)
+#define INTENS_P2       (1 << 2)
+#define INTENS_P3       (1 << 3)
+#define INTENS_C        (1 << 31)
+#define INTENS_MASK     0x8000000f      /* Mask for writable bits */
+
+/*
+ * EVTSEL: Event selection reg
+ */
+#define EVTSEL_MASK     0x7f            /* Mask for writable bits */
+
+/*
+ * SELECT: Counter selection reg
+ */
+#define SELECT_MASK     0x1f            /* Mask for writable bits */
+
+/*
+ * FLAG: counters overflow flag status reg
+ */
+#define FLAG_P0         (1 << 0)
+#define FLAG_P1         (1 << 1)
+#define FLAG_P2         (1 << 2)
+#define FLAG_P3         (1 << 3)
+#define FLAG_C          (1 << 31)
+#define FLAG_MASK       0x8000000f      /* Mask for writable bits */
+
+
+int armv7_setup_pmu(void);
+int armv7_start_pmu(void);
+int armv7_stop_pmu(void);
+int armv7_request_interrupts(int *, int);
+void armv7_release_interrupts(int *, int);
+
+#endif