Add initial DTrace support for RISC-V.

Sponsored by:	DARPA, AFRL
Sponsored by:	HEIF5

21 files changed, 1383 insertions, 6 deletions

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c
index f574cf7..ba5919d 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_link.c
@@ -250,6 +250,9 @@ printf("%s:%s(%d): DOODAD\n",__FUNCTION__,__FILE__,__LINE__);
 			    dofr[j].dofr_offset + 4;
 			rel->r_info = ELF32_R_INFO(count + dep->de_global,
 			    R_PPC_REL32);
+#elif defined(__riscv__)
+/* XXX */
+printf("%s:%s(%d): DOODAD\n",__FUNCTION__,__FILE__,__LINE__);
 #elif defined(__sparc)
 			/*
 			 * Add 4 bytes to hit the low half of this 64-bit
@@ -440,6 +443,8 @@ prepare_elf64(dtrace_hdl_t *dtp, const dof_hdr_t *dof, dof_elf64_t *dep)
 			    dofr[j].dofr_offset;
 			rel->r_info = ELF64_R_INFO(count + dep->de_global,
 			    R_PPC64_REL64);
+#elif defined(__riscv__)
+/* XXX */
 #elif defined(__i386) || defined(__amd64)
 			rel->r_offset = s->dofs_offset +
 			    dofr[j].dofr_offset;
@@ -935,7 +940,15 @@ dt_modtext(dtrace_hdl_t *dtp, char *p, int isenabled, GElf_Rela *rela,
 
 	return (0);
 }
-
+#elif defined(__riscv__)
+/* XXX */
+static int
+dt_modtext(dtrace_hdl_t *dtp, char *p, int isenabled, GElf_Rela *rela,
+    uint32_t *off)
+{
+printf("%s:%s(%d): DOODAD\n",__FUNCTION__,__FILE__,__LINE__);
+	return (0);
+}
 #elif defined(__sparc)
 
 #define	DT_OP_RET		0x81c7e008
diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_printf.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_printf.c
index d408aed..01659b5 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_printf.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_printf.c
@@ -310,7 +310,8 @@ pfprint_fp(dtrace_hdl_t *dtp, FILE *fp, const char *format,
 	case sizeof (double):
 		return (dt_printf(dtp, fp, format,
 		    *((double *)addr) / n));
-#if !defined(__arm__) && !defined(__powerpc__) && !defined(__mips__)
+#if !defined(__arm__) && !defined(__powerpc__) && \
+    !defined(__mips__) && !defined(__riscv__)
 	case sizeof (long double):
 		return (dt_printf(dtp, fp, format,
 		    *((long double *)addr) / ldn));
diff --git a/cddl/contrib/opensolaris/lib/libdtrace/riscv/dt_isadep.c b/cddl/contrib/opensolaris/lib/libdtrace/riscv/dt_isadep.c
new file mode 100644
index 0000000..9f5af85
--- /dev/null
+++ b/cddl/contrib/opensolaris/lib/libdtrace/riscv/dt_isadep.c
@@ -0,0 +1,139 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ * Copyright 2014 Howard Su
+ * Copyright 2015 George V. Neville-Neil
+ * Copyright 2015 Ruslan Bukin <br@bsdpad.com>
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <libgen.h>
+
+#include <dt_impl.h>
+#include <dt_pid.h>
+
+#if !defined(sun)
+#include <libproc_compat.h>
+#endif
+
+/*ARGSUSED*/
+int
+dt_pid_create_entry_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+    fasttrap_probe_spec_t *ftp, const GElf_Sym *symp)
+{
+
+	ftp->ftps_type = DTFTP_ENTRY;
+	ftp->ftps_pc = (uintptr_t)symp->st_value;
+	ftp->ftps_size = (size_t)symp->st_size;
+	ftp->ftps_noffs = 1;
+	ftp->ftps_offs[0] = 0;
+
+	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
+		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
+		    strerror(errno));
+		return (dt_set_errno(dtp, errno));
+	}
+
+	return (1);
+}
+
+int
+dt_pid_create_return_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+    fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, uint64_t *stret)
+{
+
+	dt_dprintf("%s: unimplemented\n", __func__);
+
+	return (DT_PROC_ERR);
+}
+
+/*ARGSUSED*/
+int
+dt_pid_create_offset_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+    fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, ulong_t off)
+{
+
+	if (!ALIGNED_POINTER(off, 4))
+		return (DT_PROC_ALIGN);
+
+	ftp->ftps_type = DTFTP_OFFSETS;
+	ftp->ftps_pc = (uintptr_t)symp->st_value;
+	ftp->ftps_size = (size_t)symp->st_size;
+	ftp->ftps_noffs = 1;
+	ftp->ftps_offs[0] = off;
+
+	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
+		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
+		    strerror(errno));
+		return (dt_set_errno(dtp, errno));
+	}
+
+	return (1);
+}
+
+/*ARGSUSED*/
+int
+dt_pid_create_glob_offset_probes(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+    fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, const char *pattern)
+{
+	ulong_t i;
+
+	ftp->ftps_type = DTFTP_OFFSETS;
+	ftp->ftps_pc = (uintptr_t)symp->st_value;
+	ftp->ftps_size = (size_t)symp->st_size;
+	ftp->ftps_noffs = 0;
+
+	/*
+	 * If we're matching against everything, just iterate through each
+	 * instruction in the function, otherwise look for matching offset
+	 * names by constructing the string and comparing it against the
+	 * pattern.
+	 */
+	if (strcmp("*", pattern) == 0) {
+		for (i = 0; i < symp->st_size; i += 4) {
+			ftp->ftps_offs[ftp->ftps_noffs++] = i;
+		}
+	} else {
+		char name[sizeof (i) * 2 + 1];
+
+		for (i = 0; i < symp->st_size; i += 4) {
+			(void) sprintf(name, "%lx", i);
+			if (gmatch(name, pattern))
+				ftp->ftps_offs[ftp->ftps_noffs++] = i;
+		}
+	}
+
+	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
+		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
+		    strerror(errno));
+		return (dt_set_errno(dtp, errno));
+	}
+
+	return (ftp->ftps_noffs);
+}
diff --git a/cddl/lib/Makefile b/cddl/lib/Makefile
index 2bfc6c1..9371865 100644
--- a/cddl/lib/Makefile
+++ b/cddl/lib/Makefile
@@ -26,7 +26,7 @@ _libzpool=	libzpool
 .endif
 .endif
 
-.if ${MACHINE_CPUARCH} != "sparc64" && ${MACHINE_CPUARCH} != "riscv"
+.if ${MACHINE_CPUARCH} != "sparc64"
 _drti=		drti
 _libdtrace=	libdtrace
 .endif
diff --git a/cddl/lib/libdtrace/Makefile b/cddl/lib/libdtrace/Makefile
index 642357f..080865c 100644
--- a/cddl/lib/libdtrace/Makefile
+++ b/cddl/lib/libdtrace/Makefile
@@ -95,6 +95,10 @@ CFLAGS+=	-I${OPENSOLARIS_SYS_DISTDIR}/uts/mips
 CFLAGS+=	-I${OPENSOLARIS_SYS_DISTDIR}/uts/powerpc
 .PATH:		${.CURDIR}/../../../cddl/contrib/opensolaris/lib/libdtrace/powerpc
 .PATH:		${.CURDIR}/../../../sys/cddl/dev/dtrace/powerpc
+.elif ${MACHINE_CPUARCH} == "riscv"
+CFLAGS+=	-I${OPENSOLARIS_SYS_DISTDIR}/uts/riscv
+.PATH:		${.CURDIR}/../../../cddl/contrib/opensolaris/lib/libdtrace/riscv
+.PATH:		${.CURDIR}/../../../sys/cddl/dev/dtrace/riscv
 .elif ${MACHINE_CPUARCH} == "sparc64"
 CFLAGS+=	-I${OPENSOLARIS_SYS_DISTDIR}/uts/sparc
 .PATH:		${.CURDIR}/../../../cddl/contrib/opensolaris/lib/libdtrace/sparc
diff --git a/cddl/usr.sbin/Makefile b/cddl/usr.sbin/Makefile
index 07dc671..ff96d85 100644
--- a/cddl/usr.sbin/Makefile
+++ b/cddl/usr.sbin/Makefile
@@ -26,7 +26,8 @@ _lockstat=	lockstat
 _plockstat=	plockstat
 .endif
 
-.if ${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "arm"
+.if ${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "arm" || \
+    ${MACHINE_CPUARCH} == "riscv"
 _dtrace=	dtrace
 _lockstat=	lockstat
 .endif
diff --git a/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c b/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c
index 086d778..c2cfd82 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c
@@ -12026,7 +12026,7 @@ err:
 
 	*factor = 1;
 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \
-    defined(__mips__) || defined(__powerpc__)
+    defined(__mips__) || defined(__powerpc__) || defined(__riscv__)
 	/*
 	 * FreeBSD isn't good at limiting the amount of memory we
 	 * ask to malloc, so let's place a limit here before trying
diff --git a/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h b/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h
index 730b423..cd5f4d0 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h
@@ -2495,6 +2495,16 @@ extern void dtrace_helpers_destroy(proc_t *);
 
 #define	DTRACE_INVOP_SD		1
 #define	DTRACE_INVOP_LD		2
+
+#elif defined(__riscv__)
+
+#define	SD_RA_SP_MASK		0x1fff07f
+#define	SD_RA_SP		0x0113023
+
+#define	DTRACE_INVOP_SD		1
+#define	DTRACE_INVOP_RET	2
+#define	DTRACE_INVOP_NOP	3
+
 #endif
 
 #ifdef	__cplusplus
diff --git a/sys/cddl/contrib/opensolaris/uts/riscv/dtrace/fasttrap_isa.c b/sys/cddl/contrib/opensolaris/uts/riscv/dtrace/fasttrap_isa.c
new file mode 100644
index 0000000..17ef0f3a
--- /dev/null
+++ b/sys/cddl/contrib/opensolaris/uts/riscv/dtrace/fasttrap_isa.c
@@ -0,0 +1,29 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*
+ *	XXX: Placeholder for RISC-V fasttrap code
+ */
diff --git a/sys/cddl/contrib/opensolaris/uts/riscv/sys/fasttrap_isa.h b/sys/cddl/contrib/opensolaris/uts/riscv/sys/fasttrap_isa.h
new file mode 100644
index 0000000..9d164e4
--- /dev/null
+++ b/sys/cddl/contrib/opensolaris/uts/riscv/sys/fasttrap_isa.h
@@ -0,0 +1,46 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#ifndef	_FASTTRAP_ISA_H
+#define	_FASTTRAP_ISA_H
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <sys/types.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+typedef uint32_t	fasttrap_instr_t;
+
+/* XXX: Place for RISC-V fasttrap headers */
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* _FASTTRAP_ISA_H */
diff --git a/sys/cddl/dev/dtrace/riscv/dtrace_asm.S b/sys/cddl/dev/dtrace/riscv/dtrace_asm.S
new file mode 100644
index 0000000..da20458
--- /dev/null
+++ b/sys/cddl/dev/dtrace/riscv/dtrace_asm.S
@@ -0,0 +1,176 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ *
+ * Portions Copyright 2016 Ruslan Bukin <br@bsdpad.com>
+ *
+ * $FreeBSD$
+ */
+/*
+ * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#define _ASM
+#define _LOCORE
+
+#include <sys/cpuvar_defs.h>
+#include <sys/dtrace.h>
+
+#include <machine/riscvreg.h>
+#include <machine/asm.h>
+
+#include "assym.s"
+
+/*
+void dtrace_membar_producer(void)
+*/
+ENTRY(dtrace_membar_producer)
+	RET
+END(dtrace_membar_producer)
+
+/*
+void dtrace_membar_consumer(void)
+*/
+ENTRY(dtrace_membar_consumer)
+	RET
+END(dtrace_membar_consumer)
+
+/*
+dtrace_icookie_t dtrace_interrupt_disable(void)
+*/
+ENTRY(dtrace_interrupt_disable)
+	csrci	sstatus, 1
+	RET
+END(dtrace_interrupt_disable)
+
+/*
+void dtrace_interrupt_enable(dtrace_icookie_t cookie)
+*/
+ENTRY(dtrace_interrupt_enable)
+	csrsi	sstatus, 1
+	RET
+END(dtrace_interrupt_enable)
+/*
+uint8_t
+dtrace_fuword8_nocheck(void *addr)
+*/
+ENTRY(dtrace_fuword8_nocheck)
+	lb	a0, 0(a0)
+	RET
+END(dtrace_fuword8_nocheck)
+
+/*
+uint16_t
+dtrace_fuword16_nocheck(void *addr)
+*/
+ENTRY(dtrace_fuword16_nocheck)
+	lh	a0, 0(a0)
+	RET
+END(dtrace_fuword16_nocheck)
+
+/*
+uint32_t
+dtrace_fuword32_nocheck(void *addr)
+*/
+ENTRY(dtrace_fuword32_nocheck)
+	lw	a0, 0(a0)
+	RET
+END(dtrace_fuword32_nocheck)
+
+/*
+uint64_t
+dtrace_fuword64_nocheck(void *addr)
+*/
+ENTRY(dtrace_fuword64_nocheck)
+	ld	a0, 0(a0)
+	RET
+END(dtrace_fuword64_nocheck)
+
+/*
+void
+dtrace_copy(uintptr_t uaddr, uintptr_t kaddr, size_t size)
+*/
+ENTRY(dtrace_copy)
+	beqz	a2, 2f		/* If len == 0 then skip loop */
+1:
+	lb	a4, 0(a0)	/* Load from uaddr */
+	addi	a0, a0, 1
+	sb	a4, 0(a1)	/* Store in kaddr */
+	addi	a1, a1, 1
+	addi	a2, a2, -1	/* len-- */
+	bnez	a2, 1b
+2:
+	RET
+END(dtrace_copy)
+
+/*
+void
+dtrace_copystr(uintptr_t uaddr, uintptr_t kaddr, size_t size,
+    volatile uint16_t *flags)
+XXX: Check for flags?
+*/
+ENTRY(dtrace_copystr)
+	beqz	a2, 2f		/* If len == 0 then skip loop */
+	lb	a4, 0(a0)	/* Load from uaddr */
+	addi	a0, a0, 1
+	sb	a4, 0(a1)	/* Store in kaddr */
+	addi	a1, a1, 1
+	beqz	a4, 2f		/* If == 0 then break */
+	addi	a2, a2, -1	/* len-- */
+	bnez	a2, 1b
+2:
+	RET
+END(dtrace_copystr)
+
+/*
+uintptr_t
+dtrace_caller(int aframes)
+*/
+ENTRY(dtrace_caller)
+	li	a0, -1
+	RET
+END(dtrace_caller)
+
+/*
+uint32_t
+dtrace_cas32(uint32_t *target, uint32_t cmp, uint32_t new)
+*/
+ENTRY(dtrace_cas32)
+1:	lr.w	a3, 0(a0)	/* Load target */
+	bne	a3, a1, 2f	/* *target != cmp ? return */
+	sc.w	a4, a2, 0(a0)	/* Store new to target */
+	bnez	a4, 1b		/* Try again if store not succeed */
+2:	mv	a0, a3		/* Return the value loaded from target */
+	RET
+END(dtrace_cas32)
+
+/*
+void *
+dtrace_casptr(volatile void *target, volatile void *cmp, volatile void *new)
+*/
+ENTRY(dtrace_casptr)
+1:	lr.d	a3, 0(a0)	/* Load target */
+	bne	a3, a1, 2f	/* *target != cmp ? return */
+	sc.d	a4, a2, 0(a0)	/* Store new to target */
+	bnez	a4, 1b		/* Try again if store not succeed */
+2:	mv	a0, a3		/* Return the value loaded from target */
+	RET
+END(dtrace_casptr)
diff --git a/sys/cddl/dev/dtrace/riscv/dtrace_isa.c b/sys/cddl/dev/dtrace/riscv/dtrace_isa.c
new file mode 100644
index 0000000..955d2cb
--- /dev/null
+++ b/sys/cddl/dev/dtrace/riscv/dtrace_isa.c
@@ -0,0 +1,394 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ *
+ * Portions Copyright 2016 Ruslan Bukin <br@bsdpad.com>
+ *
+ * $FreeBSD$
+ */
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+#include <sys/cdefs.h>
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/stack.h>
+#include <sys/pcpu.h>
+
+#include <machine/frame.h>
+#include <machine/md_var.h>
+#include <machine/reg.h>
+
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+#include <vm/pmap.h>
+
+#include <machine/atomic.h>
+#include <machine/db_machdep.h>
+#include <machine/md_var.h>
+#include <machine/stack.h>
+#include <ddb/db_sym.h>
+#include <ddb/ddb.h>
+#include <sys/kdb.h>
+
+#include "regset.h"
+
+/*
+ * Wee need some reasonable default to prevent backtrace code
+ * from wandering too far
+ */
+#define	MAX_FUNCTION_SIZE 0x10000
+#define	MAX_PROLOGUE_SIZE 0x100
+#define	MAX_USTACK_DEPTH  2048
+
+uint8_t dtrace_fuword8_nocheck(void *);
+uint16_t dtrace_fuword16_nocheck(void *);
+uint32_t dtrace_fuword32_nocheck(void *);
+uint64_t dtrace_fuword64_nocheck(void *);
+
+void
+dtrace_getpcstack(pc_t *pcstack, int pcstack_limit, int aframes,
+    uint32_t *intrpc)
+{
+	struct unwind_state state;
+	int scp_offset;
+	register_t sp;
+	int depth;
+
+	depth = 0;
+
+	if (intrpc != 0) {
+		pcstack[depth++] = (pc_t) intrpc;
+	}
+
+	aframes++;
+
+	__asm __volatile("mv %0, sp" : "=&r" (sp));
+
+	state.fp = (uint64_t)__builtin_frame_address(0);
+	state.sp = sp;
+	state.pc = (uint64_t)dtrace_getpcstack;
+
+	while (depth < pcstack_limit) {
+		if (unwind_frame(&state))
+			break;
+
+		if (!INKERNEL(state.pc) || !INKERNEL(state.fp))
+			break;
+
+		/*
+		 * NB: Unlike some other architectures, we don't need to
+		 * explicitly insert cpu_dtrace_caller as it appears in the
+		 * normal kernel stack trace rather than a special trap frame.
+		 */
+		if (aframes > 0) {
+			aframes--;
+		} else {
+			pcstack[depth++] = state.pc;
+		}
+
+	}
+
+	for (; depth < pcstack_limit; depth++) {
+		pcstack[depth] = 0;
+	}
+}
+
+static int
+dtrace_getustack_common(uint64_t *pcstack, int pcstack_limit, uintptr_t pc,
+    uintptr_t fp)
+{
+	volatile uint16_t *flags;
+	uintptr_t oldfp;
+	int ret;
+
+	ret = 0;
+	flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags;
+
+	ASSERT(pcstack == NULL || pcstack_limit > 0);
+
+	while (pc != 0) {
+		/*
+		 * We limit the number of times we can go around this
+		 * loop to account for a circular stack.
+		 */
+		if (ret++ >= MAX_USTACK_DEPTH) {
+			*flags |= CPU_DTRACE_BADSTACK;
+			cpu_core[curcpu].cpuc_dtrace_illval = fp;
+			break;
+		}
+
+		if (pcstack != NULL) {
+			*pcstack++ = (uint64_t)pc;
+			pcstack_limit--;
+			if (pcstack_limit <= 0)
+				break;
+		}
+
+		if (fp == 0)
+			break;
+
+		pc = dtrace_fuword64((void *)(fp +
+		    offsetof(struct riscv_frame, f_retaddr)));
+		fp = dtrace_fuword64((void *)fp);
+
+		if (fp == oldfp) {
+			*flags |= CPU_DTRACE_BADSTACK;
+			cpu_core[curcpu].cpuc_dtrace_illval = fp;
+			break;
+		}
+	}
+
+	return (ret);
+}
+
+void
+dtrace_getupcstack(uint64_t *pcstack, int pcstack_limit)
+{
+	volatile uint16_t *flags;
+	struct trapframe *tf;
+	uintptr_t pc, sp, fp;
+	proc_t *p;
+	int n;
+
+	p = curproc;
+	flags = (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags;
+
+	if (*flags & CPU_DTRACE_FAULT)
+		return;
+
+	if (pcstack_limit <= 0)
+		return;
+
+	/*
+	 * If there's no user context we still need to zero the stack.
+	 */
+	if (p == NULL || (tf = curthread->td_frame) == NULL)
+		goto zero;
+
+	*pcstack++ = (uint64_t)p->p_pid;
+	pcstack_limit--;
+
+	if (pcstack_limit <= 0)
+		return;
+
+	pc = tf->tf_sepc;
+	sp = tf->tf_sp;
+	fp = tf->tf_s[0];
+
+	if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) {
+		/*
+		 * In an entry probe.  The frame pointer has not yet been
+		 * pushed (that happens in the function prologue).  The
+		 * best approach is to add the current pc as a missing top
+		 * of stack and back the pc up to the caller, which is stored
+		 * at the current stack pointer address since the call
+		 * instruction puts it there right before the branch.
+		 */
+
+		*pcstack++ = (uint64_t)pc;
+		pcstack_limit--;
+		if (pcstack_limit <= 0)
+			return;
+
+		pc = tf->tf_ra;
+	}
+
+	n = dtrace_getustack_common(pcstack, pcstack_limit, pc, fp);
+	ASSERT(n >= 0);
+	ASSERT(n <= pcstack_limit);
+
+	pcstack += n;
+	pcstack_limit -= n;
+
+zero:
+	while (pcstack_limit-- > 0)
+		*pcstack++ = 0;
+}
+
+int
+dtrace_getustackdepth(void)
+{
+
+	printf("IMPLEMENT ME: %s\n", __func__);
+
+	return (0);
+}
+
+void
+dtrace_getufpstack(uint64_t *pcstack, uint64_t *fpstack, int pcstack_limit)
+{
+
+	printf("IMPLEMENT ME: %s\n", __func__);
+}
+
+/*ARGSUSED*/
+uint64_t
+dtrace_getarg(int arg, int aframes)
+{
+
+	printf("IMPLEMENT ME: %s\n", __func__);
+
+	return (0);
+}
+
+int
+dtrace_getstackdepth(int aframes)
+{
+	struct unwind_state state;
+	int scp_offset;
+	register_t sp;
+	int depth;
+	int done;
+
+	depth = 1;
+	done = 0;
+
+	__asm __volatile("mv %0, sp" : "=&r" (sp));
+
+	state.fp = (uint64_t)__builtin_frame_address(0);
+	state.sp = sp;
+	state.pc = (uint64_t)dtrace_getstackdepth;
+
+	do {
+		done = unwind_frame(&state);
+		if (!INKERNEL(state.pc) || !INKERNEL(state.fp))
+			break;
+		depth++;
+	} while (!done);
+
+	if (depth < aframes)
+		return (0);
+	else
+		return (depth - aframes);
+}
+
+ulong_t
+dtrace_getreg(struct trapframe *rp, uint_t reg)
+{
+
+	printf("IMPLEMENT ME: %s\n", __func__);
+
+	return (0);
+}
+
+static int
+dtrace_copycheck(uintptr_t uaddr, uintptr_t kaddr, size_t size)
+{
+
+	if (uaddr + size > VM_MAXUSER_ADDRESS || uaddr + size < uaddr) {
+		DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
+		cpu_core[curcpu].cpuc_dtrace_illval = uaddr;
+		return (0);
+	}
+
+	return (1);
+}
+
+void
+dtrace_copyin(uintptr_t uaddr, uintptr_t kaddr, size_t size,
+    volatile uint16_t *flags)
+{
+
+	if (dtrace_copycheck(uaddr, kaddr, size))
+		dtrace_copy(uaddr, kaddr, size);
+}
+
+void
+dtrace_copyout(uintptr_t kaddr, uintptr_t uaddr, size_t size,
+    volatile uint16_t *flags)
+{
+
+	if (dtrace_copycheck(uaddr, kaddr, size))
+		dtrace_copy(kaddr, uaddr, size);
+}
+
+void
+dtrace_copyinstr(uintptr_t uaddr, uintptr_t kaddr, size_t size,
+    volatile uint16_t *flags)
+{
+
+	if (dtrace_copycheck(uaddr, kaddr, size))
+		dtrace_copystr(uaddr, kaddr, size, flags);
+}
+
+void
+dtrace_copyoutstr(uintptr_t kaddr, uintptr_t uaddr, size_t size,
+    volatile uint16_t *flags)
+{
+
+	if (dtrace_copycheck(uaddr, kaddr, size))
+		dtrace_copystr(kaddr, uaddr, size, flags);
+}
+
+uint8_t
+dtrace_fuword8(void *uaddr)
+{
+
+	if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) {
+		DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
+		cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr;
+		return (0);
+	}
+
+	return (dtrace_fuword8_nocheck(uaddr));
+}
+
+uint16_t
+dtrace_fuword16(void *uaddr)
+{
+
+	if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) {
+		DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
+		cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr;
+		return (0);
+	}
+
+	return (dtrace_fuword16_nocheck(uaddr));
+}
+
+uint32_t
+dtrace_fuword32(void *uaddr)
+{
+
+	if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) {
+		DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
+		cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr;
+		return (0);
+	}
+
+	return (dtrace_fuword32_nocheck(uaddr));
+}
+
+uint64_t
+dtrace_fuword64(void *uaddr)
+{
+
+	if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) {
+		DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
+		cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr;
+		return (0);
+	}
+
+	return (dtrace_fuword64_nocheck(uaddr));
+}
diff --git a/sys/cddl/dev/dtrace/riscv/dtrace_subr.c b/sys/cddl/dev/dtrace/riscv/dtrace_subr.c
new file mode 100644
index 0000000..90d15fc
--- /dev/null
+++ b/sys/cddl/dev/dtrace/riscv/dtrace_subr.c
@@ -0,0 +1,282 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ *
+ * Portions Copyright 2016 Ruslan Bukin <br@bsdpad.com>
+ *
+ * $FreeBSD$
+ *
+ */
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/types.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/kmem.h>
+#include <sys/smp.h>
+#include <sys/dtrace_impl.h>
+#include <sys/dtrace_bsd.h>
+#include <machine/vmparam.h>
+#include <machine/riscvreg.h>
+#include <machine/riscv_opcode.h>
+#include <machine/clock.h>
+#include <machine/frame.h>
+#include <machine/trap.h>
+#include <vm/pmap.h>
+
+extern dtrace_id_t	dtrace_probeid_error;
+extern int (*dtrace_invop_jump_addr)(struct trapframe *);
+extern void dtrace_getnanotime(struct timespec *tsp);
+
+int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t);
+void dtrace_invop_init(void);
+void dtrace_invop_uninit(void);
+
+typedef struct dtrace_invop_hdlr {
+	int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t);
+	struct dtrace_invop_hdlr *dtih_next;
+} dtrace_invop_hdlr_t;
+
+dtrace_invop_hdlr_t *dtrace_invop_hdlr;
+
+int
+dtrace_invop(uintptr_t addr, struct trapframe *frame, uintptr_t eax)
+{
+	dtrace_invop_hdlr_t *hdlr;
+	int rval;
+
+	for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next)
+		if ((rval = hdlr->dtih_func(addr, frame, eax)) != 0)
+			return (rval);
+
+	return (0);
+}
+
+
+void
+dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t))
+{
+	dtrace_invop_hdlr_t *hdlr;
+
+	hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP);
+	hdlr->dtih_func = func;
+	hdlr->dtih_next = dtrace_invop_hdlr;
+	dtrace_invop_hdlr = hdlr;
+}
+
+void
+dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t))
+{
+	dtrace_invop_hdlr_t *hdlr, *prev;
+
+	hdlr = dtrace_invop_hdlr;
+	prev = NULL;
+
+	for (;;) {
+		if (hdlr == NULL)
+			panic("attempt to remove non-existent invop handler");
+
+		if (hdlr->dtih_func == func)
+			break;
+
+		prev = hdlr;
+		hdlr = hdlr->dtih_next;
+	}
+
+	if (prev == NULL) {
+		ASSERT(dtrace_invop_hdlr == hdlr);
+		dtrace_invop_hdlr = hdlr->dtih_next;
+	} else {
+		ASSERT(dtrace_invop_hdlr != hdlr);
+		prev->dtih_next = hdlr->dtih_next;
+	}
+
+	kmem_free(hdlr, 0);
+}
+
+/*ARGSUSED*/
+void
+dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit))
+{
+
+	(*func)(0, (uintptr_t)VM_MIN_KERNEL_ADDRESS);
+}
+
+void
+dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg)
+{
+	cpuset_t cpus;
+
+	if (cpu == DTRACE_CPUALL)
+		cpus = all_cpus;
+	else
+		CPU_SETOF(cpu, &cpus);
+
+	smp_rendezvous_cpus(cpus, smp_no_rendevous_barrier, func,
+	    smp_no_rendevous_barrier, arg);
+}
+
+static void
+dtrace_sync_func(void)
+{
+
+}
+
+void
+dtrace_sync(void)
+{
+
+	dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL);
+}
+
+/*
+ * DTrace needs a high resolution time function which can
+ * be called from a probe context and guaranteed not to have
+ * instrumented with probes itself.
+ *
+ * Returns nanoseconds since boot.
+ */
+uint64_t
+dtrace_gethrtime()
+{
+	struct timespec curtime;
+
+	nanouptime(&curtime);
+
+	return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec);
+
+}
+
+uint64_t
+dtrace_gethrestime(void)
+{
+	struct timespec current_time;
+
+	dtrace_getnanotime(&current_time);
+
+	return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec);
+}
+
+/* Function to handle DTrace traps during probes. See riscv/riscv/trap.c */
+int
+dtrace_trap(struct trapframe *frame, u_int type)
+{
+	/*
+	 * A trap can occur while DTrace executes a probe. Before
+	 * executing the probe, DTrace blocks re-scheduling and sets
+	 * a flag in it's per-cpu flags to indicate that it doesn't
+	 * want to fault. On returning from the probe, the no-fault
+	 * flag is cleared and finally re-scheduling is enabled.
+	 *
+	 * Check if DTrace has enabled 'no-fault' mode:
+	 *
+	 */
+
+	if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) {
+		/*
+		 * There are only a couple of trap types that are expected.
+		 * All the rest will be handled in the usual way.
+		 */
+		switch (type) {
+		case EXCP_LOAD_ACCESS_FAULT:
+		case EXCP_STORE_ACCESS_FAULT:
+		case EXCP_INSTR_ACCESS_FAULT:
+			/* Flag a bad address. */
+			cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR;
+			cpu_core[curcpu].cpuc_dtrace_illval = 0;
+
+			/*
+			 * Offset the instruction pointer to the instruction
+			 * following the one causing the fault.
+			 */
+			frame->tf_sepc += 4;
+
+			return (1);
+		default:
+			/* Handle all other traps in the usual way. */
+			break;
+		}
+	}
+
+	/* Handle the trap in the usual way. */
+	return (0);
+}
+
+void
+dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which,
+    int fault, int fltoffs, uintptr_t illval)
+{
+
+	dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state,
+	    (uintptr_t)epid,
+	    (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs);
+}
+
+static int
+dtrace_invop_start(struct trapframe *frame)
+{
+	int data, invop, reg, update_sp;
+	register_t arg1, arg2;
+	register_t *sp;
+	uint32_t imm;
+	InstFmt i;
+	int offs;
+	int tmp;
+
+	invop = dtrace_invop(frame->tf_sepc, frame, frame->tf_sepc);
+
+	if (invop == RISCV_INSN_RET) {
+		frame->tf_sepc = frame->tf_ra;
+		return (0);
+	}
+
+	if ((invop & SD_RA_SP_MASK) == SD_RA_SP) {
+		i.word = invop;
+		imm = i.SType.imm0_4 | (i.SType.imm5_11 << 5);
+		sp = (register_t *)((uint8_t *)frame->tf_sp + imm);
+		*sp = frame->tf_ra;
+		frame->tf_sepc += INSN_SIZE;
+		return (0);
+	}
+
+	return (-1);
+}
+
+void
+dtrace_invop_init(void)
+{
+
+	dtrace_invop_jump_addr = dtrace_invop_start;
+}
+
+void
+dtrace_invop_uninit(void)
+{
+
+	dtrace_invop_jump_addr = 0;
+}
diff --git a/sys/cddl/dev/dtrace/riscv/regset.h b/sys/cddl/dev/dtrace/riscv/regset.h
new file mode 100644
index 0000000..f99b48f
--- /dev/null
+++ b/sys/cddl/dev/dtrace/riscv/regset.h
@@ -0,0 +1,51 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ *
+ * $FreeBSD$ 
+ */
+/*
+ * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*	Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
+
+/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T		*/
+/*	All Rights Reserved	*/
+
+#ifndef	_REGSET_H
+#define	_REGSET_H
+
+/*
+ * #pragma ident	"@(#)regset.h	1.11	05/06/08 SMI"
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Place here */
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* _REGSET_H */
diff --git a/sys/cddl/dev/fbt/riscv/fbt_isa.c b/sys/cddl/dev/fbt/riscv/fbt_isa.c
new file mode 100644
index 0000000..a8ff9ad
--- /dev/null
+++ b/sys/cddl/dev/fbt/riscv/fbt_isa.c
@@ -0,0 +1,165 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ *
+ * Portions Copyright 2006-2008 John Birrell jb@freebsd.org
+ * Portions Copyright 2013 Justin Hibbits jhibbits@freebsd.org
+ * Portions Copyright 2013 Howard Su howardsu@freebsd.org
+ * Portions Copyright 2016 Ruslan Bukin <br@bsdpad.com>
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#include <sys/cdefs.h>
+#include <sys/param.h>
+
+#include <sys/dtrace.h>
+
+#include <machine/riscvreg.h>
+
+#include "fbt.h"
+
+#define	FBT_PATCHVAL		(RISCV_INSN_BREAK)
+#define	FBT_ENTRY		"entry"
+#define	FBT_RETURN		"return"
+
+int
+fbt_invop(uintptr_t addr, struct trapframe *frame, uintptr_t rval)
+{
+	solaris_cpu_t *cpu;
+	fbt_probe_t *fbt;
+
+	cpu = &solaris_cpu[curcpu];
+	fbt = fbt_probetab[FBT_ADDR2NDX(addr)];
+
+	for (; fbt != NULL; fbt = fbt->fbtp_hashnext) {
+		if ((uintptr_t)fbt->fbtp_patchpoint == addr) {
+			cpu->cpu_dtrace_caller = addr;
+
+			dtrace_probe(fbt->fbtp_id, frame->tf_a[0],
+			    frame->tf_a[1], frame->tf_a[2],
+			    frame->tf_a[3], frame->tf_a[4]);
+
+			cpu->cpu_dtrace_caller = 0;
+			return (fbt->fbtp_savedval);
+		}
+	}
+
+	return (0);
+}
+
+void
+fbt_patch_tracepoint(fbt_probe_t *fbt, fbt_patchval_t val)
+{
+
+	*fbt->fbtp_patchpoint = val;
+	cpu_icache_sync_range((vm_offset_t)fbt->fbtp_patchpoint, 4);
+}
+
+int
+fbt_provide_module_function(linker_file_t lf, int symindx,
+    linker_symval_t *symval, void *opaque)
+{
+	fbt_probe_t *fbt, *retfbt;
+	uint32_t *target, *start;
+	uint32_t *instr, *limit;
+	const char *name;
+	char *modname;
+	int offs;
+
+	modname = opaque;
+	name = symval->name;
+
+	/* Check if function is excluded from instrumentation */
+	if (fbt_excluded(name))
+		return (0);
+
+	instr = (uint32_t *)(symval->value);
+	limit = (uint32_t *)(symval->value + symval->size);
+
+	/* Look for sd operation */
+	for (; instr < limit; instr++) {
+		if ((*instr & SD_RA_SP_MASK) == SD_RA_SP)
+			break;
+	}
+
+	if (instr >= limit)
+		return (0);
+
+	fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO);
+	fbt->fbtp_name = name;
+	fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
+	    name, FBT_ENTRY, 3, fbt);
+	fbt->fbtp_patchpoint = instr;
+	fbt->fbtp_ctl = lf;
+	fbt->fbtp_loadcnt = lf->loadcnt;
+	fbt->fbtp_savedval = *instr;
+	fbt->fbtp_patchval = FBT_PATCHVAL;
+	fbt->fbtp_rval = DTRACE_INVOP_SD;
+	fbt->fbtp_symindx = symindx;
+
+	fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
+	fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;
+
+	lf->fbt_nentries++;
+
+	retfbt = NULL;
+again:
+	for (; instr < limit; instr++) {
+		if (*instr == RISCV_INSN_RET)
+			break;
+	}
+
+	if (instr >= limit)
+		return (0);
+
+	/*
+	 * We have a winner!
+	 */
+	fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO);
+	fbt->fbtp_name = name;
+	if (retfbt == NULL) {
+		fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
+		    name, FBT_RETURN, 3, fbt);
+	} else {
+		retfbt->fbtp_next = fbt;
+		fbt->fbtp_id = retfbt->fbtp_id;
+	}
+	retfbt = fbt;
+
+	fbt->fbtp_patchpoint = instr;
+	fbt->fbtp_ctl = lf;
+	fbt->fbtp_loadcnt = lf->loadcnt;
+	fbt->fbtp_symindx = symindx;
+	fbt->fbtp_rval = DTRACE_INVOP_RET;
+	fbt->fbtp_savedval = *instr;
+	fbt->fbtp_patchval = FBT_PATCHVAL;
+	fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
+	fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;
+
+	lf->fbt_nentries++;
+
+	instr++;
+	goto again;
+}
diff --git a/sys/cddl/dev/fbt/riscv/fbt_isa.h b/sys/cddl/dev/fbt/riscv/fbt_isa.h
new file mode 100644
index 0000000..5552f31
--- /dev/null
+++ b/sys/cddl/dev/fbt/riscv/fbt_isa.h
@@ -0,0 +1,30 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ *
+ * $FreeBSD$
+ *
+ */
+
+#ifndef _FBT_ISA_H_
+#define _FBT_ISA_H_
+
+typedef uint32_t fbt_patchval_t;
+
+#endif
diff --git a/sys/cddl/dev/profile/profile.c b/sys/cddl/dev/profile/profile.c
index 4deac87..3b58424 100644
--- a/sys/cddl/dev/profile/profile.c
+++ b/sys/cddl/dev/profile/profile.c
@@ -143,6 +143,11 @@ struct profile_probe_percpu;
 #define	PROF_ARTIFICIAL_FRAMES	10
 #endif
 
+#ifdef __riscv__
+/* TODO: verify */
+#define	PROF_ARTIFICIAL_FRAMES	10
+#endif
+
 typedef struct profile_probe {
 	char		prof_name[PROF_NAMELEN];
 	dtrace_id_t	prof_id;
diff --git a/sys/conf/files.riscv b/sys/conf/files.riscv
index 1840185..fe30078 100644
--- a/sys/conf/files.riscv
+++ b/sys/conf/files.riscv
@@ -1,4 +1,8 @@
 # $FreeBSD$
+cddl/compat/opensolaris/kern/opensolaris_atomic.c	optional zfs | dtrace compile-with "${CDDL_C}"
+cddl/dev/dtrace/riscv/dtrace_asm.S			optional dtrace compile-with "${DTRACE_S}"
+cddl/dev/dtrace/riscv/dtrace_subr.c			optional dtrace compile-with "${DTRACE_C}"
+cddl/dev/fbt/riscv/fbt_isa.c				optional dtrace_fbt | dtraceall compile-with "${FBT_C}"
 crypto/blowfish/bf_enc.c	optional	crypto | ipsec
 crypto/des/des_enc.c		optional	crypto | ipsec | netsmb
 dev/ofw/ofw_cpu.c		optional	fdt
diff --git a/sys/riscv/include/frame.h b/sys/riscv/include/frame.h
index e74d926..d0756f7 100644
--- a/sys/riscv/include/frame.h
+++ b/sys/riscv/include/frame.h
@@ -59,6 +59,11 @@ struct trapframe {
 	uint64_t tf_scause;
 };
 
+struct riscv_frame {
+	struct riscv_frame	*f_frame;
+	u_long			f_retaddr;
+};
+
 /*
  * Signal frame. Pushed onto user stack before calling sigcode.
  */
diff --git a/sys/riscv/include/riscvreg.h b/sys/riscv/include/riscvreg.h
index a71ee47..6984ab1 100644
--- a/sys/riscv/include/riscvreg.h
+++ b/sys/riscv/include/riscvreg.h
@@ -124,6 +124,11 @@
 #define	XLEN		8
 #define	INSN_SIZE	4
 
+#define	INSN_SIZE		4
+#define	RISCV_INSN_NOP		0x00000013
+#define	RISCV_INSN_BREAK	0x00100073
+#define	RISCV_INSN_RET		0x00008067
+
 #define	CSR_ZIMM(val)							\
 	(__builtin_constant_p(val) && ((u_long)(val) < 32))
 
diff --git a/sys/riscv/riscv/trap.c b/sys/riscv/riscv/trap.c
index 6327204..22d27f4 100644
--- a/sys/riscv/riscv/trap.c
+++ b/sys/riscv/riscv/trap.c
@@ -64,6 +64,12 @@ __FBSDID("$FreeBSD$");
 #include <machine/resource.h>
 #include <machine/intr.h>
 
+#ifdef KDTRACE_HOOKS
+#include <sys/dtrace_bsd.h>
+#endif
+
+int (*dtrace_invop_jump_addr)(struct trapframe *);
+
 extern register_t fsu_intr_fault;
 
 /* Called from exception.S */
@@ -271,6 +277,11 @@ do_trap_supervisor(struct trapframe *frame)
 		return;
 	}
 
+#ifdef KDTRACE_HOOKS
+	if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, exception))
+		return;
+#endif
+
 	CTR3(KTR_TRAP, "do_trap_supervisor: curthread: %p, sepc: %lx, frame: %p",
 	    curthread, frame->tf_sepc, frame);
 
@@ -281,6 +292,12 @@ do_trap_supervisor(struct trapframe *frame)
 		data_abort(frame, 0);
 		break;
 	case EXCP_INSTR_BREAKPOINT:
+#ifdef KDTRACE_HOOKS
+		if (dtrace_invop_jump_addr != 0) {
+			dtrace_invop_jump_addr(frame);
+			break;
+		}
+#endif
 #ifdef KDB
 		kdb_trap(exception, 0, frame);
 #else
@@ -290,7 +307,7 @@ do_trap_supervisor(struct trapframe *frame)
 		break;
 	case EXCP_INSTR_ILLEGAL:
 		dump_regs(frame);
-		panic("Illegal instruction at %x\n", frame->tf_sepc);
+		panic("Illegal instruction at 0x%016lx\n", frame->tf_sepc);
 		break;
 	default:
 		dump_regs(frame);