risc-v: initial 64 bit port, static only (no TLS/NPTL)

Only a simple hello world is tested in qemu system emulation.

12 files changed, 709 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/riscv64/bits/endian.h b/libc/sysdeps/linux/riscv64/bits/endian.h
new file mode 100644
index 000000000..4aaf559d4
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/endian.h
@@ -0,0 +1,5 @@
+#ifndef _ENDIAN_H
+# error "Never use <bits/endian.h> directly; include <endian.h> instead."
+#endif
+
+#define __BYTE_ORDER __LITTLE_ENDIAN
diff --git a/libc/sysdeps/linux/riscv64/bits/fcntl.h b/libc/sysdeps/linux/riscv64/bits/fcntl.h
new file mode 100644
index 000000000..a08bbf5b5
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/fcntl.h
@@ -0,0 +1,228 @@
+/* O_*, F_*, FD_* bit values for Linux.
+ *
+ * Licensed under the LGPL v2.1 or later, see the file 
+ * COPYING.LIB in this tarball.
+ */
+
+#ifndef	_FCNTL_H
+# error "Never use <bits/fcntl.h> directly; include <fcntl.h> instead."
+#endif
+
+#include <sys/types.h>
+#ifdef __USE_GNU
+# include <bits/uio.h>
+#endif
+
+/* open/fcntl - O_SYNC is only implemented on blocks devices and on files
+   located on an ext2 file system */
+#define O_ACCMODE	00000003
+#define O_RDONLY	00000000
+#define O_WRONLY	00000001
+#define O_RDWR		00000002
+#define O_CREAT		00000100	/* not fcntl */
+#define O_EXCL		00000200	/* not fcntl */
+#define O_NOCTTY	00000400	/* not fcntl */
+#define O_TRUNC		00001000	/* not fcntl */
+#define O_APPEND	00002000
+#define O_NONBLOCK	00004000
+#define O_NDELAY	O_NONBLOCK
+#define O_SYNC		00010000
+#define O_FSYNC		O_SYNC
+#define O_ASYNC		00020000
+
+#ifdef __USE_XOPEN2K8
+# define O_DIRECTORY	00200000	/* Must be a directory.	 */
+# define O_NOFOLLOW	00400000	/* Do not follow links.	 */
+# define O_CLOEXEC	02000000	/* Set close_on_exec.  */
+#endif
+
+#ifdef __USE_GNU
+# define O_DIRECT	00040000	/* Direct disk access.	*/
+# define O_NOATIME	01000000	/* Do not set atime.  */
+# define O_PATH		010000000  	/* Resolve pathname but do not open file.  */
+#endif
+
+#ifdef __USE_LARGEFILE64
+# define O_LARGEFILE	00100000
+#endif
+
+/* For now Linux has synchronisity options for data and read operations.
+   We define the symbols here but let them do the same as O_SYNC since
+   this is a superset.	*/
+#if defined __USE_POSIX199309 || defined __USE_UNIX98
+# define O_DSYNC	O_SYNC	/* Synchronize data.  */
+# define O_RSYNC	O_SYNC	/* Synchronize read operations.	 */
+#endif
+
+/* Values for the second argument to `fcntl'.  */
+#define F_DUPFD		0	/* Duplicate file descriptor.  */
+#define F_GETFD		1	/* Get file descriptor flags.  */
+#define F_SETFD		2	/* Set file descriptor flags.  */
+#define F_GETFL		3	/* Get file status flags.  */
+#define F_SETFL		4	/* Set file status flags.  */
+
+#ifndef __USE_FILE_OFFSET64
+# define F_GETLK	5	/* Get record locking info.  */
+# define F_SETLK	6	/* Set record locking info (non-blocking).  */
+# define F_SETLKW	7	/* Set record locking info (blocking).	*/
+#else
+# define F_GETLK	F_GETLK64  /* Get record locking info.	*/
+# define F_SETLK	F_SETLK64  /* Set record locking info (non-blocking).*/
+# define F_SETLKW	F_SETLKW64 /* Set record locking info (blocking).  */
+#endif
+#define F_GETLK64	12	/* Get record locking info.  */
+#define F_SETLK64	13	/* Set record locking info (non-blocking).  */
+#define F_SETLKW64	14	/* Set record locking info (blocking).	*/
+
+#if defined __USE_BSD || defined __USE_XOPEN2K
+# define F_SETOWN	8	/* Get owner of socket (receiver of SIGIO).  */
+# define F_GETOWN	9	/* Set owner of socket (receiver of SIGIO).  */
+#endif
+
+#ifdef __USE_GNU
+# define F_SETSIG	10	/* Set number of signal to be sent.  */
+# define F_GETSIG	11	/* Get number of signal to be sent.  */
+#endif
+
+#ifdef __USE_GNU
+# define F_SETLEASE	1024	/* Set a lease.	 */
+# define F_GETLEASE	1025	/* Enquire what lease is active.  */
+# define F_NOTIFY	1026	/* Request notfications on a directory.	 */
+# define F_DUPFD_CLOEXEC 1030	/* Duplicate file descriptor with
+				   close-on-exit set on new fd.  */
+# define F_SETPIPE_SZ	1031    /* Set pipe page size array.  */
+# define F_GETPIPE_SZ	1032    /* Get pipe page size array.  */
+#endif
+
+/* For F_[GET|SET]FL.  */
+#define FD_CLOEXEC	1	/* actually anything with low bit set goes */
+
+/* For posix fcntl() and `l_type' field of a `struct flock' for lockf().  */
+#define F_RDLCK		0	/* Read lock.  */
+#define F_WRLCK		1	/* Write lock.	*/
+#define F_UNLCK		2	/* Remove lock.	 */
+
+/* For old implementation of bsd flock().  */
+#define F_EXLCK		4	/* or 3 */
+#define F_SHLCK		8	/* or 4 */
+
+#ifdef __USE_BSD
+/* Operations for bsd flock(), also used by the kernel implementation.	*/
+# define LOCK_SH	1	/* shared lock */
+# define LOCK_EX	2	/* exclusive lock */
+# define LOCK_NB	4	/* or'd with one of the above to prevent
+				   blocking */
+# define LOCK_UN	8	/* remove lock */
+#endif
+
+#ifdef __USE_GNU
+# define LOCK_MAND	32	/* This is a mandatory flock:	*/
+# define LOCK_READ	64	/* ... which allows concurrent read operations.	 */
+# define LOCK_WRITE	128	/* ... which allows concurrent write operations.  */
+# define LOCK_RW	192	/* ... Which allows concurrent read & write operations.	 */
+#endif
+
+#ifdef __USE_GNU
+/* Types of directory notifications that may be requested with F_NOTIFY.  */
+# define DN_ACCESS	0x00000001	/* File accessed.  */
+# define DN_MODIFY	0x00000002	/* File modified.  */
+# define DN_CREATE	0x00000004	/* File created.  */
+# define DN_DELETE	0x00000008	/* File removed.  */
+# define DN_RENAME	0x00000010	/* File renamed.  */
+# define DN_ATTRIB	0x00000020	/* File changed attibutes.  */
+# define DN_MULTISHOT	0x80000000	/* Don't remove notifier.  */
+#endif
+
+struct flock
+  {
+    short int l_type;	/* Type of lock: F_RDLCK, F_WRLCK, or F_UNLCK.	*/
+    short int l_whence;	/* Where `l_start' is relative to (like `lseek').  */
+#ifndef __USE_FILE_OFFSET64
+    __off_t l_start;	/* Offset where the lock begins.  */
+    __off_t l_len;	/* Size of the locked area; zero means until EOF.  */
+#else
+    __off64_t l_start;	/* Offset where the lock begins.  */
+    __off64_t l_len;	/* Size of the locked area; zero means until EOF.  */
+#endif
+    __pid_t l_pid;	/* Process holding the lock.  */
+  };
+
+#ifdef __USE_LARGEFILE64
+struct flock64
+  {
+    short int l_type;	/* Type of lock: F_RDLCK, F_WRLCK, or F_UNLCK.	*/
+    short int l_whence;	/* Where `l_start' is relative to (like `lseek').  */
+    __off64_t l_start;	/* Offset where the lock begins.  */
+    __off64_t l_len;	/* Size of the locked area; zero means until EOF.  */
+    __pid_t l_pid;	/* Process holding the lock.  */
+  };
+#endif
+
+/* Define some more compatibility macros to be backward compatible with
+   BSD systems which did not managed to hide these kernel macros.  */
+#ifdef	__USE_BSD
+# define FAPPEND	O_APPEND
+# define FFSYNC		O_FSYNC
+# define FASYNC		O_ASYNC
+# define FNONBLOCK	O_NONBLOCK
+# define FNDELAY	O_NDELAY
+#endif /* Use BSD.  */
+
+/* Advise to `posix_fadvise'.  */
+#ifdef __USE_XOPEN2K
+# define POSIX_FADV_NORMAL	0 /* No further special treatment.  */
+# define POSIX_FADV_RANDOM	1 /* Expect random page references.  */
+# define POSIX_FADV_SEQUENTIAL	2 /* Expect sequential page references.	 */
+# define POSIX_FADV_WILLNEED	3 /* Will need these pages.  */
+# define POSIX_FADV_DONTNEED	4 /* Don't need these pages.  */
+# define POSIX_FADV_NOREUSE	5 /* Data will be accessed once.  */
+#endif
+
+#if defined __USE_GNU && defined __UCLIBC_LINUX_SPECIFIC__
+/* Flags for SYNC_FILE_RANGE.  */
+# define SYNC_FILE_RANGE_WAIT_BEFORE	1 /* Wait upon writeout of all pages
+					     in the range before performing the
+					     write.  */
+# define SYNC_FILE_RANGE_WRITE		2 /* Initiate writeout of all those
+					     dirty pages in the range which are
+					     not presently under writeback.  */
+# define SYNC_FILE_RANGE_WAIT_AFTER	4 /* Wait upon writeout of all pages in
+					     the range after performing the
+					     write.  */
+
+/* Flags for SPLICE and VMSPLICE.  */
+# define SPLICE_F_MOVE		1	/* Move pages instead of copying.  */
+# define SPLICE_F_NONBLOCK	2	/* Don't block on the pipe splicing
+					   (but we may still block on the fd
+					   we splice from/to).  */
+# define SPLICE_F_MORE		4	/* Expect more data.  */
+# define SPLICE_F_GIFT		8	/* Pages passed in are a gift.  */
+#endif
+
+__BEGIN_DECLS
+
+#if defined __USE_GNU && defined __UCLIBC_LINUX_SPECIFIC__
+
+/* Provide kernel hint to read ahead.  */
+extern ssize_t readahead (int __fd, __off64_t __offset, size_t __count)
+    __THROW;
+
+/* Selective file content synch'ing.  */
+extern int sync_file_range (int __fd, __off64_t __from, __off64_t __to,
+			    unsigned int __flags);
+
+/* Splice address range into a pipe.  */
+extern ssize_t vmsplice (int __fdout, const struct iovec *__iov,
+			 size_t __count, unsigned int __flags);
+
+/* Splice two files together.  */
+extern ssize_t splice (int __fdin, __off64_t *__offin, int __fdout,
+		       __off64_t *__offout, size_t __len,
+		       unsigned int __flags);
+
+/* In-kernel implementation of tee for pipe buffers.  */
+extern ssize_t tee (int __fdin, int __fdout, size_t __len,
+		    unsigned int __flags);
+
+#endif
+__END_DECLS
diff --git a/libc/sysdeps/linux/riscv64/bits/fenv.h b/libc/sysdeps/linux/riscv64/bits/fenv.h
new file mode 100644
index 000000000..a3f8031af
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/fenv.h
@@ -0,0 +1,73 @@
+/* Floating point environment, RISC-V version.
+   Copyright (C) 1998-2018 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _FENV_H
+# error "Never use <bits/fenv.h> directly; include <fenv.h> instead."
+#endif
+
+enum
+  {
+    FE_INEXACT   =
+#define FE_INEXACT	(0x01)
+      FE_INEXACT,
+    FE_UNDERFLOW =
+#define FE_UNDERFLOW	(0x02)
+      FE_UNDERFLOW,
+    FE_OVERFLOW  =
+#define FE_OVERFLOW	(0x04)
+      FE_OVERFLOW,
+    FE_DIVBYZERO =
+#define FE_DIVBYZERO	(0x08)
+      FE_DIVBYZERO,
+    FE_INVALID   =
+#define FE_INVALID	(0x10)
+      FE_INVALID
+  };
+
+#define FE_ALL_EXCEPT \
+	(FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
+
+enum
+  {
+    FE_TONEAREST  =
+#define FE_TONEAREST	(0x0)
+      FE_TONEAREST,
+    FE_TOWARDZERO =
+#define FE_TOWARDZERO	(0x1)
+      FE_TOWARDZERO,
+    FE_DOWNWARD   =
+#define FE_DOWNWARD	(0x2)
+      FE_DOWNWARD,
+    FE_UPWARD     =
+#define FE_UPWARD	(0x3)
+      FE_UPWARD
+  };
+
+
+typedef unsigned int fexcept_t;
+typedef unsigned int fenv_t;
+
+/* If the default argument is used we use this value.  */
+#define FE_DFL_ENV	((__const fenv_t *) -1)
+
+#if __GLIBC_USE (IEC_60559_BFP_EXT)
+/* Type representing floating-point control modes.  */
+typedef unsigned int femode_t;
+
+/* Default floating-point control modes.  */
+# define FE_DFL_MODE	((const femode_t *) -1L)
+#endif
diff --git a/libc/sysdeps/linux/riscv64/bits/kernel_types.h b/libc/sysdeps/linux/riscv64/bits/kernel_types.h
new file mode 100644
index 000000000..832b17674
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/kernel_types.h
@@ -0,0 +1,42 @@
+/* Note that we use the exact same include guard #define names
+ * as asm/posix_types.h.  This will avoid gratuitous conflicts
+ * with the posix_types.h kernel header, and will ensure that
+ * our private content, and not the kernel header, will win.
+ *  -Erik
+ */
+#ifndef __ASM_GENERIC_POSIX_TYPES_H
+#define __ASM_GENERIC_POSIX_TYPES_H
+
+typedef unsigned long		__kernel_dev_t;
+typedef unsigned long		__kernel_ino_t;
+typedef unsigned int		__kernel_mode_t;
+typedef unsigned int		__kernel_nlink_t;
+typedef long			__kernel_off_t;
+typedef int			__kernel_pid_t;
+typedef int 			__kernel_ipc_pid_t;
+typedef unsigned int		__kernel_uid_t;
+typedef unsigned int		__kernel_gid_t;
+typedef unsigned long		__kernel_size_t;
+typedef long			__kernel_ssize_t;
+typedef long			__kernel_ptrdiff_t;
+typedef long			__kernel_time_t;
+typedef long			__kernel_suseconds_t;
+typedef long			__kernel_clock_t;
+typedef int			__kernel_daddr_t;
+typedef char *			__kernel_caddr_t;
+typedef unsigned short		__kernel_uid16_t;
+typedef unsigned short		__kernel_gid16_t;
+typedef unsigned int		__kernel_uid32_t;
+typedef unsigned int		__kernel_gid32_t;
+typedef unsigned short 		__kernel_old_uid_t;
+typedef unsigned short 		__kernel_old_gid_t;
+typedef long long		__kernel_loff_t;
+typedef unsigned int		__kernel_old_dev_t;
+typedef long			__kernel_long_t;
+typedef unsigned long		__kernel_ulong_t;
+
+typedef struct {
+	int	val[2];
+} __kernel_fsid_t;
+
+#endif /* __ASM_GENERIC_POSIX_TYPES_H */
diff --git a/libc/sysdeps/linux/riscv64/bits/mman.h b/libc/sysdeps/linux/riscv64/bits/mman.h
new file mode 100644
index 000000000..316f87d99
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/mman.h
@@ -0,0 +1,37 @@
+/* Definitions for POSIX memory map interface.  Linux/RISC-V version.
+   Copyright (C) 1997-2018 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_MMAN_H
+# error "Never use <bits/mman.h> directly; include <sys/mman.h> instead."
+#endif
+
+#ifdef __USE_MISC
+# define MAP_GROWSDOWN	0x00100		/* Stack-like segment.  */
+# define MAP_DENYWRITE	0x00800		/* ETXTBSY.  */
+# define MAP_EXECUTABLE	0x01000		/* Mark it as an executable.  */
+# define MAP_LOCKED	0x02000		/* Lock the mapping.  */
+# define MAP_NORESERVE	0x04000		/* Don't check for reservations.  */
+# define MAP_POPULATE	0x08000		/* Populate (prefault) pagetables.  */
+# define MAP_NONBLOCK	0x10000		/* Do not block on IO.  */
+# define MAP_STACK	0x20000		/* Allocation is for a stack.  */
+# define MAP_HUGETLB	0x40000		/* Create huge page mapping.  */
+# define MAP_SYNC	0x80000		/* Perform synchronous page
+					   faults for the mapping.  */
+#endif
+
+/* Include generic Linux declarations.  */
+#include <bits/mman-linux.h>
diff --git a/libc/sysdeps/linux/riscv64/bits/setjmp.h b/libc/sysdeps/linux/riscv64/bits/setjmp.h
new file mode 100644
index 000000000..c45f93957
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/setjmp.h
@@ -0,0 +1,38 @@
+/* Define the machine-dependent type `jmp_buf'.  RISC-V version.
+   Copyright (C) 2011-2018 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _RISCV_BITS_SETJMP_H
+#define _RISCV_BITS_SETJMP_H
+
+typedef struct __jmp_buf_internal_tag
+  {
+    /* Program counter.  */
+    long int __pc;
+    /* Callee-saved registers.  */
+    long int __regs[12];
+    /* Stack pointer.  */
+    long int __sp;
+
+    /* Callee-saved floating point registers.  */
+#if defined __riscv_float_abi_double
+   double __fpregs[12];
+#elif !defined __riscv_float_abi_soft
+# error unsupported FLEN
+#endif
+  } __jmp_buf[1];
+
+#endif /* _RISCV_BITS_SETJMP_H */
diff --git a/libc/sysdeps/linux/riscv64/bits/shm.h b/libc/sysdeps/linux/riscv64/bits/shm.h
new file mode 100644
index 000000000..dbe4851f9
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/shm.h
@@ -0,0 +1,90 @@
+/*
+ * Licensed under the LGPL v2.1 or later, see the file COPYING.LIB
+ * in this tarball.
+ */
+
+#ifndef _SYS_SHM_H
+# error "Never include <bits/shm.h> directly; use <sys/shm.h> instead."
+#endif
+
+#include <bits/types.h>
+
+/* Permission flag for shmget.  */
+#define SHM_R		0400		/* or S_IRUGO from <linux/stat.h> */
+#define SHM_W		0200		/* or S_IWUGO from <linux/stat.h> */
+
+/* Flags for `shmat'.  */
+#define SHM_RDONLY	010000		/* attach read-only else read-write */
+#define SHM_RND		020000		/* round attach address to SHMLBA */
+#define SHM_REMAP	040000		/* take-over region on attach */
+
+/* Commands for `shmctl'.  */
+#define SHM_LOCK	11		/* lock segment (root only) */
+#define SHM_UNLOCK	12		/* unlock segment (root only) */
+
+__BEGIN_DECLS
+
+/* Segment low boundary address multiple.  */
+#define SHMLBA		(__getpagesize () << 2)
+extern int __getpagesize (void) __THROW __attribute__ ((__const__));
+
+
+/* Type to count number of attaches.  */
+typedef unsigned long int shmatt_t;
+
+/* Data structure describing a set of semaphores.  */
+struct shmid_ds
+  {
+    struct ipc_perm shm_perm;		/* operation permission struct */
+    size_t shm_segsz;			/* size of segment in bytes */
+    __time_t shm_atime;			/* time of last shmat() */
+    unsigned long int __unused1;
+    __time_t shm_dtime;			/* time of last shmdt() */
+    unsigned long int __unused2;
+    __time_t shm_ctime;			/* time of last change by shmctl() */
+    unsigned long int __unused3;
+    __pid_t shm_cpid;			/* pid of creator */
+    __pid_t shm_lpid;			/* pid of last shmop */
+    shmatt_t shm_nattch;		/* number of current attaches */
+    unsigned long int __unused4;
+    unsigned long int __unused5;
+  };
+
+#ifdef __USE_MISC
+
+/* ipcs ctl commands */
+# define SHM_STAT 	13
+# define SHM_INFO 	14
+
+/* shm_mode upper byte flags */
+# define SHM_DEST	01000	/* segment will be destroyed on last detach */
+# define SHM_LOCKED	02000   /* segment will not be swapped */
+# define SHM_HUGETLB	04000	/* segment is mapped via hugetlb */
+# define SHM_NORESERVE	010000	/* don't check for reservations */
+
+struct	shminfo
+  {
+    unsigned long int shmmax;
+    unsigned long int shmmin;
+    unsigned long int shmmni;
+    unsigned long int shmseg;
+    unsigned long int shmall;
+    unsigned long int __unused1;
+    unsigned long int __unused2;
+    unsigned long int __unused3;
+    unsigned long int __unused4;
+  };
+
+struct shm_info
+  {
+    int used_ids;
+    unsigned long int shm_tot;	/* total allocated shm */
+    unsigned long int shm_rss;	/* total resident shm */
+    unsigned long int shm_swp;	/* total swapped shm */
+    unsigned long int swap_attempts;
+    unsigned long int swap_successes;
+  };
+
+#endif /* __USE_MISC */
+
+__END_DECLS
diff --git a/libc/sysdeps/linux/riscv64/bits/sigcontext.h b/libc/sysdeps/linux/riscv64/bits/sigcontext.h
new file mode 100644
index 000000000..9b896a626
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/sigcontext.h
@@ -0,0 +1,32 @@
+/* Machine-dependent signal context structure for Linux.  RISC-V version.
+   Copyright (C) 1996-2018 Free Software
+   Foundation, Inc.  This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _BITS_SIGCONTEXT_H
+#define _BITS_SIGCONTEXT_H 1
+
+#if !defined _SIGNAL_H && !defined _SYS_UCONTEXT_H
+# error "Never use <bits/sigcontext.h> directly; include <signal.h> instead."
+#endif
+
+struct sigcontext {
+  /* gregs[0] holds the program counter.  */
+  unsigned long int gregs[32];
+  unsigned long long int fpregs[66] __attribute__ ((__aligned__ (16)));
+};
+
+#endif
diff --git a/libc/sysdeps/linux/riscv64/bits/stackinfo.h b/libc/sysdeps/linux/riscv64/bits/stackinfo.h
new file mode 100644
index 000000000..a9fd8173b
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/stackinfo.h
@@ -0,0 +1,11 @@
+/*
+ * Licensed under the LGPL v2.1 or later, see the file COPYING.LIB
+ * in this tarball.
+ */
+
+#ifndef _STACKINFO_H
+#define _STACKINFO_H	1
+
+#define _STACK_GROWS_DOWN	1
+
+#endif
diff --git a/libc/sysdeps/linux/riscv64/bits/syscalls.h b/libc/sysdeps/linux/riscv64/bits/syscalls.h
new file mode 100644
index 000000000..d1f1d9170
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/syscalls.h
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2018 by Waldemar Brodkorb <wbx@uclibc-ng.org>
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ * ported from GNU C Library
+ */
+
+#ifndef _BITS_SYSCALLS_H
+#define _BITS_SYSCALLS_H
+#ifndef _SYSCALL_H
+# error "Never use <bits/syscalls.h> directly; include <sys/syscall.h> instead."
+#endif
+
+#define INTERNAL_SYSCALL_NCS(name, err, nr, args...)	\
+  ({ long _sys_result;					\
+     {							\
+	register long int _a7 __asm__ ("a7");		\
+	LOAD_ARGS_##nr (args)				\
+	_a7 = (name);					\
+							\
+        __asm__ volatile (				\
+		"scall\n\t"				\
+		: "=r" (_a0) 				\
+		: "r"(_a7) ASM_ARGS_##nr  		\
+		: "memory"); 				\
+	_sys_result = _a0;				\
+     } 							\
+     _sys_result; 					\
+  })
+
+/* Macros for setting up inline __asm__ input regs */
+# define ASM_ARGS_0
+# define ASM_ARGS_1	, "r" (_a0)
+# define ASM_ARGS_2	ASM_ARGS_1, "r" (_a1)
+# define ASM_ARGS_3	ASM_ARGS_2, "r" (_a2)
+# define ASM_ARGS_4	ASM_ARGS_3, "r" (_a3)
+# define ASM_ARGS_5	ASM_ARGS_4, "r" (_a4)
+# define ASM_ARGS_6	ASM_ARGS_5, "r" (_a5)
+# define ASM_ARGS_7	ASM_ARGS_6, "r" (_a6)
+
+/* Macros for converting sys-call wrapper args into sys call args */
+# define LOAD_ARGS_0()				\
+  register long _a0 __asm__ ("a0");
+# define LOAD_ARGS_1(a0)			\
+  long _a0tmp;					\
+  LOAD_ARGS_0 ()				\
+  _a0tmp = (long) (a0);				\
+  _a0 = _a0tmp;
+# define LOAD_ARGS_2(a0, a1)			\
+  register long _a1 __asm__ ("a1");		\
+  long _a1tmp;					\
+  LOAD_ARGS_1 (a0)				\
+  _a1tmp = (long) (a1);				\
+  _a1 = _a1tmp;
+# define LOAD_ARGS_3(a0, a1, a2)		\
+  register long _a2 __asm__ ("a2");		\
+  long _a2tmp;					\
+  LOAD_ARGS_2 (a0, a1)				\
+  _a2tmp = (long) (a2);				\
+  _a2 = _a2tmp;
+# define LOAD_ARGS_4(a0, a1, a2, a3)		\
+  register long _a3 __asm__ ("a3");		\
+  long _a3tmp;					\
+  LOAD_ARGS_3 (a0, a1, a2)			\
+  _a3tmp = (long) (a3);				\
+  _a3 = _a3tmp;
+# define LOAD_ARGS_5(a0, a1, a2, a3, a4)	\
+  register long _a4 __asm__ ("a4");		\
+  long _a4tmp;					\
+  LOAD_ARGS_4 (a0, a1, a2, a3)			\
+  _a4tmp = (long) (a4);				\
+  _a4 = _a4tmp;
+# define LOAD_ARGS_6(a0, a1, a2, a3, a4, a5)	\
+  register long _a5 __asm__ ("a5");		\
+  long _a5tmp;					\
+  LOAD_ARGS_5 (a0, a1, a2, a3, a4)		\
+  _a5tmp = (long) (a5);				\
+  _a5 = _a5tmp;
+# define LOAD_ARGS_7(a0, a1, a2, a3, a4, a5, a6)\
+  register long _a6 __asm__ ("a6");		\
+  long _a6tmp;					\
+  LOAD_ARGS_6 (a0, a1, a2, a3, a4, a5)		\
+  _a6tmp = (long) (a6);				\
+  _a6 = _a6tmp;
+
+#endif
diff --git a/libc/sysdeps/linux/riscv64/bits/uClibc_arch_features.h b/libc/sysdeps/linux/riscv64/bits/uClibc_arch_features.h
new file mode 100644
index 000000000..b754f3227
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/uClibc_arch_features.h
@@ -0,0 +1,39 @@
+/*
+ * Track misc arch-specific features that aren't config options
+ */
+
+#ifndef _BITS_UCLIBC_ARCH_FEATURES_H
+#define _BITS_UCLIBC_ARCH_FEATURES_H
+
+#undef __UCLIBC_ABORT_INSTRUCTION__
+
+/* can your target use syscall6() for mmap ? */
+#undef __UCLIBC_MMAP_HAS_6_ARGS__
+
+#define __UCLIBC_SYSCALL_ALIGN_64BIT__
+
+/* does your target have a broken create_module() ? */
+#define __UCLIBC_BROKEN_CREATE_MODULE__
+
+/* does your target have to worry about older [gs]etrlimit() ? */
+#define __UCLIBC_HANDLE_OLDER_RLIMIT__
+
+/* does your target have an asm .set ? */
+#define __UCLIBC_HAVE_ASM_SET_DIRECTIVE__
+
+/* define if target doesn't like .global */
+#undef __UCLIBC_ASM_GLOBAL_DIRECTIVE__
+
+/* define if target supports .weak */
+#define __UCLIBC_HAVE_ASM_WEAK_DIRECTIVE__
+
+/* define if target supports .weakext */
+#undef __UCLIBC_HAVE_ASM_WEAKEXT_DIRECTIVE__
+
+/* define if target supports IEEE signed zero floats */
+#define __UCLIBC_HAVE_SIGNED_ZERO__
+
+/* define if target supports CFI pseudo ops */
+#define __UCLIBC_HAVE_ASM_CFI_DIRECTIVES__
+
+#endif /* _BITS_UCLIBC_ARCH_FEATURES_H */
diff --git a/libc/sysdeps/linux/riscv64/bits/wordsize.h b/libc/sysdeps/linux/riscv64/bits/wordsize.h
new file mode 100644
index 000000000..67a16ba62
--- /dev/null
+++ b/libc/sysdeps/linux/riscv64/bits/wordsize.h
@@ -0,0 +1,29 @@
+/* Determine the wordsize from the preprocessor defines.  RISC-V version.
+   Copyright (C) 2002-2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#if __riscv_xlen == (__SIZEOF_POINTER__ * 8)
+# define __WORDSIZE __riscv_xlen
+#else
+# error unsupported ABI
+#endif
+
+#if __riscv_xlen == 64
+# define __WORDSIZE_TIME64_COMPAT32 1
+#else
+# error "rv32i-based targets are not supported"
+#endif