Commit Graph

16 Commits

Author SHA1 Message Date
Kito Cheng 20d0081998 RISC-V: Using SYS_clock_gettime64 for rv32 libgloss.
- RISC-V 32 bits linux/glibc didn't provide gettimeofday anymore
   after upstream, because RV32 didn't have backward compatible issue,
   so RV32 only support 64 bits time related system call.

 - So using clock_gettime64 call instead for rv32 libgloss.
2021-04-13 12:54:49 +02:00
Yeting Kuo 6aa0ab1c5d RISC-V: Use __bss_start for the starting point of .bss.
It's more flexible for the positions of .bss and .data.
2021-02-05 10:29:21 +01:00
Craig Blackmore 865cd30dcc RISC-V: Add semihosting support 2020-12-16 16:40:34 -05:00
Georg Sauthoff 9b51beeb2a Only pass the minimum number of syscall arguments
Previously, __internal_syscall() compiled into asm-code that unconditionally
sets the syscall argument registers a0 to a5.

For example, the instruction sequence for a exit syscall looked like
this:

    li    a0, 1   # in ther caller of exit()
    # ...         # in newlib:
    li    a1, 0   # unused arguments
    li    a2, 0
    li    a3, 0
    li    a4, 0
    li    a5, 0
    li    a7, 93  # exit syscall number

(i.e. the binary contains then 5 superfluous instructions for this
one argument syscall)

This commit changes the RISC-V syscall code such that only the required
syscall argument registers are set.

GCC detects that argc is known at compile time and thus evaluates all the
if-statements where argc is used at compile time (tested with -O2 and -Os).
2020-02-11 09:41:52 +01:00
Jim Wilson 8ef32f2dcf RISC-V: Use newlib nano specific libm.
The libm gamma functions use the _gamma_signgam field of the reentrant
structure, which changes offset with the --enable-newlib-reent-small
configure option, which means we need to use a newlib nano specific
version of libm in addition to libc in the nano.specs file.  Reported
by Keith Packard.  There is a riscv-gnu-toolchain patch that goes
along with this to create the new libm_nano.a file.

Signed-off-by: Jim Wilson <jimw@sifive.com>
2020-01-31 12:42:52 +01:00
Jim Wilson 77ac27dcf8 RISC-V: Add _LITE_EXIT in crt0.S.
This patch adds _LITE_EXIT in crt0.S to enable "lite exit" technique in
RISC-V. The changes have been tested in riscv/riscv-gnu-toolchain by
riscv-dejagnu with riscv-sim.exp/riscv-sim-nano.exp.
2019-05-22 17:41:25 -07:00
Denis Ivanov 9e032fd939 RISC-V: Fix _sbrk, it's failed only when return value is -1.
Signed-off-by: Kito Cheng <kito.cheng@gmail.com>
2018-08-29 15:49:00 +02:00
Denis Ivanov 258996b696 RISC-V: Fixed return code in _times syscall.
Upon successful completion, times() shall return the elapsed real time,
in clock ticks, since an arbitrary point in the past (for example,
system start-up time).

Signed-off-by: Kito Cheng <kito.cheng@gmail.com>
2018-08-29 15:49:00 +02:00
Sebastian Huber 6158b30e3e RISC-V: Do not use _init/_fini
Introduce new host configuration variable "have_init_fini" which is set
to "yes" by default.  Override it for RISC-V to "no".

Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
2018-07-30 10:47:57 +02:00
Chih-Mao Chen f2c9e55faf RISC-V: isatty: return 0 on error 2018-01-18 09:21:10 +01:00
Jim Wilson 9588ff7555 RISC-V: Add gdb sim and newlib nano support. Fix a few misc minor bugs. 2017-12-26 12:31:33 -08:00
Jim Wilson 28d5b98038 RISC-V: Moved syscalls to separate files to fix aliasing problems. 2017-12-26 12:27:52 -08:00
Jim Wilson 347b083911 RISC-V: Updated syscall to take 6 arguments 2017-12-26 12:26:19 -08:00
Jim Wilson a6633677b9 RISC-V: Add nanosleep functionality 2017-12-26 12:24:45 -08:00
Kito Cheng 6864c08b94 Change license to FreeBSD License for RISC-V
- For prevent confuse about what BSD license variant we used, 2- or
   3-clause license, we change the license to FreeBSD license to make
   it unambiguously refers to the 2-clause license.
2017-08-21 11:08:54 +02:00
Kito Cheng c496cbb6bd Add RISC-V port for libgloss
Contributor list:
    - Andrew Waterman  <andrew@sifive.com>
    - Palmer Dabbelt  <palmer@dabbelt.com>
    - Kito Cheng  <kito.cheng@gmail.com>
    - Alex Suykov  <alex.suykov@gmail.com>
2017-08-17 14:51:05 -04:00