Welcome the RISC-V 64-bit kernel.

This is the final step required allowing to compile and to run RISC-V
kernel and userland from HEAD.

RISC-V is a completely open ISA that is freely available to academia
and industry.

Thanks to all the people involved! Special thanks to Andrew Turner,
David Chisnall, Ed Maste, Konstantin Belousov, John Baldwin and
Arun Thomas for their help.
Thanks to Robert Watson for organizing this project.

This project sponsored by UK Higher Education Innovation Fund (HEIF5) and
DARPA CTSRD project at the University of Cambridge Computer Laboratory.

FreeBSD/RISC-V project home: https://wiki.freebsd.org/riscv

Reviewed by:	andrew, emaste, kib
Relnotes:	Yes
Sponsored by:	DARPA, AFRL
Sponsored by:	HEIF5
Differential Revision:	https://reviews.freebsd.org/D4982

6 files changed, 238 insertions, 0 deletions

diff --git a/sys/conf/Makefile.riscv b/sys/conf/Makefile.riscv
new file mode 100644
index 0000000..27338b4
--- /dev/null
+++ b/sys/conf/Makefile.riscv
@@ -0,0 +1,49 @@
+# Makefile.riscv -- with config changes.
+# Copyright 1990 W. Jolitz
+#	from: @(#)Makefile.i386	7.1 5/10/91
+#	from FreeBSD: src/sys/conf/Makefile.i386,v 1.255 2002/02/20 23:35:49
+# $FreeBSD$
+#
+# Makefile for FreeBSD
+#
+# RISCVTODO: copy pasted from aarch64, needs to be
+# constructed from a machine description:
+#	config machineid
+# Most changes should be made in the machine description
+#	/sys/riscv/conf/``machineid''
+# after which you should do
+#	 config machineid
+# Generic makefile changes should be made in
+#	/sys/conf/Makefile.riscv
+# after which config should be rerun for all machines.
+#
+
+# Which version of config(8) is required.
+%VERSREQ=	600012
+
+.if !defined(S)
+S=	../../..
+.endif
+.include "$S/conf/kern.pre.mk"
+
+INCLUDES+= -I$S/contrib/libfdt
+
+.if !empty(DDB_ENABLED)
+CFLAGS += -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer
+.endif
+
+%BEFORE_DEPEND
+
+%OBJS
+
+%FILES.c
+
+%FILES.s
+
+%FILES.m
+
+%CLEAN
+
+%RULES
+
+.include "$S/conf/kern.post.mk"
diff --git a/sys/conf/files.riscv b/sys/conf/files.riscv
new file mode 100644
index 0000000..a101b57
--- /dev/null
+++ b/sys/conf/files.riscv
@@ -0,0 +1,44 @@
+# $FreeBSD$
+crypto/blowfish/bf_enc.c	optional	crypto | ipsec
+crypto/des/des_enc.c		optional	crypto | ipsec | netsmb
+kern/kern_clocksource.c		standard
+kern/subr_dummy_vdso_tc.c	standard
+libkern/bcmp.c			standard
+libkern/ffs.c			standard
+libkern/ffsl.c			standard
+libkern/fls.c			standard
+libkern/flsl.c			standard
+libkern/flsll.c			standard
+libkern/memmove.c		standard
+libkern/memset.c		standard
+riscv/htif/htif.c		standard
+riscv/htif/htif_block.c		standard
+riscv/htif/htif_console.c	standard
+riscv/riscv/autoconf.c		standard
+riscv/riscv/bcopy.c		standard
+riscv/riscv/bus_machdep.c	standard
+riscv/riscv/busdma_machdep.c	standard
+riscv/riscv/clock.c		standard
+riscv/riscv/copyinout.S		standard
+riscv/riscv/copystr.c		standard
+riscv/riscv/cpufunc_asm.S	standard
+riscv/riscv/devmap.c		standard
+riscv/riscv/dump_machdep.c	standard
+riscv/riscv/elf_machdep.c	standard
+riscv/riscv/intr_machdep.c	standard
+riscv/riscv/in_cksum.c		optional	inet | inet6
+riscv/riscv/identcpu.c		standard
+riscv/riscv/locore.S		standard	no-obj
+riscv/riscv/minidump_machdep.c	standard
+riscv/riscv/machdep.c		standard
+riscv/riscv/mem.c		standard
+riscv/riscv/nexus.c		standard
+riscv/riscv/pmap.c		standard
+riscv/riscv/sys_machdep.c	standard
+riscv/riscv/support.S		standard
+riscv/riscv/swtch.S		standard
+riscv/riscv/trap.c		standard
+riscv/riscv/timer.c		standard
+riscv/riscv/uio_machdep.c	standard
+riscv/riscv/uma_machdep.c	standard
+riscv/riscv/vm_machdep.c	standard
diff --git a/sys/conf/kern.mk b/sys/conf/kern.mk
index 56ddbda..fb72a97 100644
--- a/sys/conf/kern.mk
+++ b/sys/conf/kern.mk
@@ -104,6 +104,10 @@ CFLAGS += -mgeneral-regs-only
 CFLAGS += -ffixed-x18
 .endif
 
+.if ${MACHINE_CPUARCH} == "riscv"
+INLINE_LIMIT?=	8000
+.endif
+
 #
 # For sparc64 we want the medany code model so modules may be located
 # anywhere in the 64-bit address space.  We also tell GCC to use floating
diff --git a/sys/conf/kern.pre.mk b/sys/conf/kern.pre.mk
index 7860701..c9623cb 100644
--- a/sys/conf/kern.pre.mk
+++ b/sys/conf/kern.pre.mk
@@ -252,6 +252,7 @@ EMBEDFS_FORMAT.mips?=		elf32-tradbigmips
 EMBEDFS_FORMAT.mipsel?=		elf32-tradlittlemips
 EMBEDFS_FORMAT.mips64?=		elf64-tradbigmips
 EMBEDFS_FORMAT.mips64el?=	elf64-tradlittlemips
+EMBEDFS_FORMAT.riscv?=		elf64-littleriscv
 .endif
 
 # Detect kernel config options that force stack frames to be turned on.
diff --git a/sys/conf/ldscript.riscv b/sys/conf/ldscript.riscv
new file mode 100644
index 0000000..31fd5df
--- /dev/null
+++ b/sys/conf/ldscript.riscv
@@ -0,0 +1,136 @@
+/* $FreeBSD$ */
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+
+SEARCH_DIR(/usr/lib);
+SECTIONS
+{
+  /* Read-only sections, merged into text segment: */
+  . = kernbase + 0x100;
+  .text      : AT(ADDR(.text) - kernbase)
+  {
+    *(.text)
+    *(.stub)
+    /* .gnu.warning sections are handled specially by elf32.em.  */
+    *(.gnu.warning)
+    *(.gnu.linkonce.t*)
+  } =0x9090
+  _etext = .;
+  PROVIDE (etext = .);
+  .fini      : { *(.fini)    } =0x9090
+  .rodata    : { *(.rodata) *(.gnu.linkonce.r*) }
+  .rodata1   : { *(.rodata1) }
+   .interp     : { *(.interp) 	}
+  .hash          : { *(.hash)		}
+  .dynsym        : { *(.dynsym)		}
+  .dynstr        : { *(.dynstr)		}
+  .gnu.version   : { *(.gnu.version)	}
+  .gnu.version_d   : { *(.gnu.version_d)	}
+  .gnu.version_r   : { *(.gnu.version_r)	}
+  .rel.text      :
+    { *(.rel.text) *(.rel.gnu.linkonce.t*) }
+  .rela.text     :
+    { *(.rela.text) *(.rela.gnu.linkonce.t*) }
+  .rel.data      :
+    { *(.rel.data) *(.rel.gnu.linkonce.d*) }
+  .rela.data     :
+    { *(.rela.data) *(.rela.gnu.linkonce.d*) }
+  .rel.rodata    :
+    { *(.rel.rodata) *(.rel.gnu.linkonce.r*) }
+  .rela.rodata   :
+    { *(.rela.rodata) *(.rela.gnu.linkonce.r*) }
+  .rel.got       : { *(.rel.got)		}
+  .rela.got      : { *(.rela.got)		}
+  .rel.ctors     : { *(.rel.ctors)	}
+  .rela.ctors    : { *(.rela.ctors)	}
+  .rel.dtors     : { *(.rel.dtors)	}
+  .rela.dtors    : { *(.rela.dtors)	}
+  .rel.init      : { *(.rel.init)	}
+  .rela.init     : { *(.rela.init)	}
+  .rel.fini      : { *(.rel.fini)	}
+  .rela.fini     : { *(.rela.fini)	}
+  .rel.bss       : { *(.rel.bss)		}
+  .rela.bss      : { *(.rela.bss)		}
+  .rel.plt       : { *(.rel.plt)		}
+  .rela.plt      : { *(.rela.plt)		}
+  .init          : { *(.init)	} =0x9090
+  .plt      : { *(.plt)	}
+
+  /* Adjust the address for the data segment.  We want to adjust up to
+     the same address within the page on the next page up.  */
+  . = ALIGN(0x1000) + (. & (0x1000 - 1)) ;
+  .data    :
+  {
+    *(.data)
+    *(.gnu.linkonce.d*)
+    CONSTRUCTORS
+  }
+  .data1   : { *(.data1) }
+  . = ALIGN(32 / 8);
+  _start_ctors = .;
+  PROVIDE (start_ctors = .);
+  .ctors         :
+  {
+    *(.ctors)
+  }
+  _stop_ctors = .;
+  PROVIDE (stop_ctors = .);
+  .dtors         :
+  {
+    *(.dtors)
+  }
+  .got           : { *(.got.plt) *(.got) }
+  .dynamic       : { *(.dynamic) }
+  /* We want the small data sections together, so single-instruction offsets
+     can access them all, and initialized data all before uninitialized, so
+     we can shorten the on-disk segment size.  */
+  . = ALIGN(8);
+  .sdata     : { *(.sdata) }
+  _edata  =  .;
+  PROVIDE (edata = .);
+  __bss_start = .;
+  .sbss      : { *(.sbss) *(.scommon) }
+  .bss       :
+  {
+   *(.dynbss)
+   *(.bss)
+   *(COMMON)
+  }
+  . = ALIGN(8);
+  _end = . ;
+  PROVIDE (end = .);
+  /* Stabs debugging sections.  */
+  .stab 0 : { *(.stab) }
+  .stabstr 0 : { *(.stabstr) }
+  .stab.excl 0 : { *(.stab.excl) }
+  .stab.exclstr 0 : { *(.stab.exclstr) }
+  .stab.index 0 : { *(.stab.index) }
+  .stab.indexstr 0 : { *(.stab.indexstr) }
+  .comment 0 : { *(.comment) }
+  /* DWARF debug sections.
+     Symbols in the DWARF debugging sections are relative to the beginning
+     of the section so we begin them at 0.  */
+  /* DWARF 1 */
+  .debug          0 : { *(.debug) }
+  .line           0 : { *(.line) }
+  /* GNU DWARF 1 extensions */
+  .debug_srcinfo  0 : { *(.debug_srcinfo) }
+  .debug_sfnames  0 : { *(.debug_sfnames) }
+  /* DWARF 1.1 and DWARF 2 */
+  .debug_aranges  0 : { *(.debug_aranges) }
+  .debug_pubnames 0 : { *(.debug_pubnames) }
+  /* DWARF 2 */
+  .debug_info     0 : { *(.debug_info) }
+  .debug_abbrev   0 : { *(.debug_abbrev) }
+  .debug_line     0 : { *(.debug_line) }
+  .debug_frame    0 : { *(.debug_frame) }
+  .debug_str      0 : { *(.debug_str) }
+  .debug_loc      0 : { *(.debug_loc) }
+  .debug_macinfo  0 : { *(.debug_macinfo) }
+  /* SGI/MIPS DWARF 2 extensions */
+  .debug_weaknames 0 : { *(.debug_weaknames) }
+  .debug_funcnames 0 : { *(.debug_funcnames) }
+  .debug_typenames 0 : { *(.debug_typenames) }
+  .debug_varnames  0 : { *(.debug_varnames) }
+  /* These must appear regardless of  .  */
+}
diff --git a/sys/conf/options.riscv b/sys/conf/options.riscv
new file mode 100644
index 0000000..c263bd8
--- /dev/null
+++ b/sys/conf/options.riscv
@@ -0,0 +1,4 @@
+# $FreeBSD$
+
+RISCV				opt_global.h
+VFP				opt_global.h