6 files changed, 158 insertions, 0 deletions

diff --git a/arch/metag/Kconfig b/arch/metag/Kconfig
index afc8973d1488..b06b41861aac 100644
--- a/arch/metag/Kconfig
+++ b/arch/metag/Kconfig
@@ -25,6 +25,7 @@ config METAG
         select HAVE_MEMBLOCK
         select HAVE_MEMBLOCK_NODE_MAP
         select HAVE_MOD_ARCH_SPECIFIC
+        select HAVE_OPROFILE
         select HAVE_PERF_EVENTS
         select HAVE_SYSCALL_TRACEPOINTS
         select IRQ_DOMAIN
@@ -209,6 +210,9 @@ config METAG_PERFCOUNTER_IRQS
           When disabled, Performance Counters information will be collected
           based on Timer Interrupt.
 
+config HW_PERF_EVENTS
+        def_bool METAG_PERFCOUNTER_IRQS && PERF_EVENTS
+
 config METAG_DA
         bool "DA support"
         help
diff --git a/arch/metag/Makefile b/arch/metag/Makefile
index 81bd6a1c7483..b566116b171b 100644
--- a/arch/metag/Makefile
+++ b/arch/metag/Makefile
@@ -49,6 +49,8 @@ core-y					+= arch/metag/mm/
 libs-y                                  += arch/metag/lib/
 libs-y                                  += arch/metag/tbx/
 
+drivers-$(CONFIG_OPROFILE)              += arch/metag/oprofile/
+
 boot                                    := arch/metag/boot
 
 boot_targets                            += uImage
diff --git a/arch/metag/oprofile/Makefile b/arch/metag/oprofile/Makefile
new file mode 100644
index 000000000000..c9639d4734d6
--- /dev/null
+++ b/arch/metag/oprofile/Makefile
@@ -0,0 +1,17 @@
+obj-$(CONFIG_OPROFILE)  += oprofile.o
+
+oprofile-core-y += buffer_sync.o
+oprofile-core-y += cpu_buffer.o
+oprofile-core-y += event_buffer.o
+oprofile-core-y += oprof.o
+oprofile-core-y += oprofile_files.o
+oprofile-core-y += oprofile_stats.o
+oprofile-core-y += oprofilefs.o
+oprofile-core-y += timer_int.o
+oprofile-core-$(CONFIG_HW_PERF_EVENTS)  += oprofile_perf.o
+
+oprofile-y      += backtrace.o
+oprofile-y      += common.o
+oprofile-y      += $(addprefix ../../../drivers/oprofile/,$(oprofile-core-y))
+
+ccflags-y       += -Werror
diff --git a/arch/metag/oprofile/backtrace.c b/arch/metag/oprofile/backtrace.c
new file mode 100644
index 000000000000..7cc3f37cb40e
--- /dev/null
+++ b/arch/metag/oprofile/backtrace.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2010-2013 Imagination Technologies Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/oprofile.h>
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <asm/stacktrace.h>
+
+#include "backtrace.h"
+
+static void user_backtrace_fp(unsigned long __user *fp, unsigned int depth)
+{
+        while (depth-- && access_ok(VERIFY_READ, fp, 8)) {
+                unsigned long addr;
+                unsigned long __user *fpnew;
+                if (__copy_from_user_inatomic(&addr, fp + 1, sizeof(addr)))
+                        break;
+                addr -= 4;
+
+                oprofile_add_trace(addr);
+
+                /* stack grows up, so frame pointers must decrease */
+                if (__copy_from_user_inatomic(&fpnew, fp + 0, sizeof(fpnew)))
+                        break;
+                if (fpnew >= fp)
+                        break;
+                fp = fpnew;
+        }
+}
+
+static int kernel_backtrace_frame(struct stackframe *frame, void *data)
+{
+        unsigned int *depth = data;
+
+        oprofile_add_trace(frame->pc);
+
+        /* decrement depth and stop if we reach 0 */
+        if ((*depth)-- == 0)
+                return 1;
+
+        /* otherwise onto the next frame */
+        return 0;
+}
+
+void metag_backtrace(struct pt_regs * const regs, unsigned int depth)
+{
+        if (user_mode(regs)) {
+                unsigned long *fp = (unsigned long *)regs->ctx.AX[1].U0;
+                user_backtrace_fp((unsigned long __user __force *)fp, depth);
+        } else {
+                struct stackframe frame;
+                frame.fp = regs->ctx.AX[1].U0;          /* A0FrP */
+                frame.sp = user_stack_pointer(regs);    /* A0StP */
+                frame.lr = 0;                           /* from stack */
+                frame.pc = regs->ctx.CurrPC;            /* PC */
+                walk_stackframe(&frame, &kernel_backtrace_frame, &depth);
+        }
+}
diff --git a/arch/metag/oprofile/backtrace.h b/arch/metag/oprofile/backtrace.h
new file mode 100644
index 000000000000..c0fcc4265abb
--- /dev/null
+++ b/arch/metag/oprofile/backtrace.h
@@ -0,0 +1,6 @@
+#ifndef _METAG_OPROFILE_BACKTRACE_H
+#define _METAG_OPROFILE_BACKTRACE_H
+
+void metag_backtrace(struct pt_regs * const regs, unsigned int depth);
+
+#endif
diff --git a/arch/metag/oprofile/common.c b/arch/metag/oprofile/common.c
new file mode 100644
index 000000000000..ba26152b3c00
--- /dev/null
+++ b/arch/metag/oprofile/common.c
@@ -0,0 +1,66 @@
+/*
+ * arch/metag/oprofile/common.c
+ *
+ * Copyright (C) 2013 Imagination Technologies Ltd.
+ *
+ * Based on arch/sh/oprofile/common.c:
+ *
+ * Copyright (C) 2003 - 2010  Paul Mundt
+ *
+ * Based on arch/mips/oprofile/common.c:
+ *
+ *      Copyright (C) 2004, 2005 Ralf Baechle
+ *      Copyright (C) 2005 MIPS Technologies, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/oprofile.h>
+#include <linux/perf_event.h>
+#include <linux/slab.h>
+
+#include "backtrace.h"
+
+#ifdef CONFIG_HW_PERF_EVENTS
+/*
+ * This will need to be reworked when multiple PMUs are supported.
+ */
+static char *metag_pmu_op_name;
+
+char *op_name_from_perf_id(void)
+{
+        return metag_pmu_op_name;
+}
+
+int __init oprofile_arch_init(struct oprofile_operations *ops)
+{
+        ops->backtrace = metag_backtrace;
+
+        if (perf_num_counters() == 0)
+                return -ENODEV;
+
+        metag_pmu_op_name = kasprintf(GFP_KERNEL, "metag/%s",
+                                      perf_pmu_name());
+        if (unlikely(!metag_pmu_op_name))
+                return -ENOMEM;
+
+        return oprofile_perf_init(ops);
+}
+
+void oprofile_arch_exit(void)
+{
+        oprofile_perf_exit();
+        kfree(metag_pmu_op_name);
+}
+#else
+int __init oprofile_arch_init(struct oprofile_operations *ops)
+{
+        ops->backtrace = metag_backtrace;
+        /* fall back to timer interrupt PC sampling */
+        return -ENODEV;
+}
+void oprofile_arch_exit(void) {}
+#endif /* CONFIG_HW_PERF_EVENTS */