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authorWaldemar Brodkorb <wbx@openadk.org>2016-02-05 21:07:40 +0100
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2016-02-07 18:23:22 +0100
commitc0a2d0b7edacbc6389574821b0231e07431dabb6 (patch)
treef2d21c6e2fe8f99ccd820d1d406dc5d51419ba77 /libc/sysdeps/linux/frv/crt1.S
parentb499fe614ac5b492fc0fdc6e1fbbeeb904674159 (diff)
frv: resurrect port somehow, totally untested
The FR-V port is really broken, and I have no emulator or hardware for this platform. I tried to get some hardware from RedHat, who made the FR-V port initially. Unfortunately Fujitsi didn't agreed to sent me some of their unused spare hardware lying @RedHat. As I invested some time to get stuff compiled, I decided to add the code and may be anytime later I can gain access to some emulator or hardware. GDB simulator for FR-V doesn't support booting Linux AFAIK.
Diffstat (limited to 'libc/sysdeps/linux/frv/crt1.S')
-rw-r--r--libc/sysdeps/linux/frv/crt1.S121
1 files changed, 121 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/frv/crt1.S b/libc/sysdeps/linux/frv/crt1.S
new file mode 100644
index 000000000..0827feae7
--- /dev/null
+++ b/libc/sysdeps/linux/frv/crt1.S
@@ -0,0 +1,121 @@
+/* Copyright (C) 1991, 1992, 2003, 2004 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
+Library General Public License for more details.
+
+In addition to the permissions in the GNU Lesser General Public
+License, the Free Software Foundation gives you unlimited
+permission to link the compiled version of this file with other
+programs, and to distribute those programs without any restriction
+coming from the use of this file. (The GNU Lesser General Public
+License restrictions do apply in other respects; for example, they
+cover modification of the file, and distribution when not linked
+into another program.)
+
+You should have received a copy of the GNU Lesser General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, see <http://www.gnu.org/licenses/>. */
+
+
+/* Based on ../i386/crt0.S and newlib's libgloss/frv/crt0.S */
+
+/*
+ When we enter this piece of code, the program stack looks like this:
+ argc argument counter (integer)
+ argv[0] program name (pointer)
+ argv[1...N] program args (pointers)
+ argv[argc-1] end of args (integer)
+ NULL
+ env[0...N] environment variables (pointers)
+ NULL
+
+ Also, GR16 holds a pointer to a memory map. */
+
+#include <features.h>
+
+ .text
+ .global _start
+ .type _start,%function
+ .weak _init
+ .weak _fini
+ .type __uClibc_main,%function
+
+_start:
+ /* Make sure the stack pointer is properly aligned. Save the
+ original value in gr21 such that we can get to arguments and
+ such from there. */
+ mov.p sp, gr21
+ andi sp, #-8, sp
+ /* At program start-up, gr16 contains a pointer to a memory
+ map, that we use to relocate addresses. */
+ call .Lcall
+.Lcall:
+ movsg lr, gr4
+ sethi.p #gprelhi(.Lcall), gr5
+ setlo #gprello(.Lcall), gr5
+ sub.p gr4, gr5, gr4
+ /* gr4 now holds the _gp address. */
+
+ mov gr16, gr8
+ sethi.p #gprelhi(__ROFIXUP_LIST__), gr9
+ sethi #gprelhi(__ROFIXUP_END__), gr10
+ setlo.p #gprello(__ROFIXUP_LIST__), gr9
+ setlo #gprello(__ROFIXUP_END__), gr10
+ add.p gr9, gr4, gr9
+ add gr10, gr4, gr10
+ call __self_reloc
+ mov.p gr8, gr17
+ mov gr8, gr15
+ /* gr17 now holds the self-relocated _GLOBAL_OFFSET_TABLE_
+ address, because the linker added its unrelocated address as
+ the last entry in the ROFIXUP list, and __self_reloc returns
+ the last entry, relocated. */
+
+ /* Prepare arguments for uClibc main. */
+ ld @(gr21, gr0), gr8
+ slli gr8, #2, gr10
+ add gr21, gr10, gr10
+ addi.p gr21, #4, gr9
+ addi gr10, #8, gr10
+
+ /* Set up an invalid (NULL return address, NULL frame pointer)
+ callers stack frame so anybody unrolling the stack knows where
+ to stop */
+ mov gr0, fp
+ movgs gr0, lr
+
+#if (defined L_crt1 || defined L_Scrt1) && defined __UCLIBC_CTOR_DTOR__
+ /* Pass .init and .fini arguments to __uClibc_start_main(). */
+ sethi.p #gotfuncdeschi(_init), gr11
+ sethi #gotfuncdeschi(_fini), gr12
+ setlo.p #gotfuncdesclo(_init), gr11
+ setlo #gotfuncdesclo(_fini), gr12
+ ld.p @(gr11, gr17), gr11
+ mov gr17, gr15
+ ld.p @(gr12, gr17), gr12
+ call __uClibc_main
+#else
+ mov.p gr17, gr15
+ call __uClibc_main
+#endif
+
+ /* Crash if somehow `exit' returns anyways. */
+ jmpl @(gr0,gr0)
+.size _start,.-_start
+
+/* Define a symbol for the first piece of initialized data. */
+ .data
+ .globl __data_start
+__data_start:
+ .long 0
+ .weak data_start
+ data_start = __data_start
+