+++ /dev/null
-// crt1-tiny.S
-//
-// This is a reduced version of the code in crt1-boards.S .
-// For most hardware / boards, this code sets up the C calling context
-// (setting up stack, PS, and clearing BSS) and calls main().
-// It has some limitations (see LSP Ref Manual for details) such as:
-// - does not setup the C library (...)
-// - does not call C++ static constructors and destructors
-// - only clears .bss , not other *.bss sections
-//
-// Control arrives here at _start from the reset vector or from crt0-app.S.
-
-// Copyright (c) 1998-2010 Tensilica Inc.
-//
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-//
-// The above copyright notice and this permission notice shall be included
-// in all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
-// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
-// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
-// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
-// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-#include <xtensa/coreasm.h>
-
-
-// Imports
-// __stack from linker script (see LSP Ref Manual)
-// _bss_start from linker script (see LSP Ref Manual)
-// _bss_end from linker script (see LSP Ref Manual)
-// main from user application
-
-
-
-#ifdef __XTENSA_CALL0_ABI__
-# define CALL call0
-#else
-# define CALL call4
-#endif
-
-
-/**************************************************************************/
-
- .text
- .global _start
-_start:
- // _start is typically NOT at the beginning of the text segment --
- // it is always called from either the reset vector or other code
- // that does equivalent initialization (such as crt0-app.S).
- // See crt1-boards.S for assumptions on entry to _start ,
- // and for comments on what is being done in this file.
-
-#if !XCHAL_HAVE_HALT || !XCHAL_HAVE_BOOTLOADER // not needed for Xtensa TX
- movi a0, 0 // mark base of call stack
-#endif
-
- movi sp, __stack // setup the stack
-
-#if XCHAL_HAVE_EXCEPTIONS
-# ifdef __XTENSA_CALL0_ABI__
- movi a3, PS_UM // PS: WOE=0, UM=1, EXCM=0, INTLEVEL=0
-# else
- movi a3, PS_UM|PS_WOE // PS: WOE=1, UM=1, EXCM=0, INTLEVEL=0
-# endif
- wsr a3, PS // setup PS for the application
- rsync
-#endif
-
-
- // Clear the BSS (uninitialized data) segment.
- //
- // This code only supports .bss, not multiple *.bss sections.
- // Corresponding code in crt1-boards.S does, and is faster but bigger.
-
-#if !XCHAL_HAVE_BOOTLOADER
- movi a6, _bss_start
- movi a7, _bss_end
- bgeu a6, a7, 2f
-1: s32i a0, a6, 0
- addi a6, a6, 4
- bltu a6, a7, 1b
-2:
-#endif
-
- // We can now call C code, the C calling environment is initialized.
- // This tiny C runtime assumes main is declared as "void main(void)"
- // rather than with the usual argc,argv. So there are no arguments.
-
- CALL main
-
- // In this tiny C runtime, main() is not expected to return.
- // If it does, just loop forever.
-
- //CALL xthal_dcache_all_writeback // sync dirty dcaches to memory
- //extw // sync TIE queues/ports/etc (LX or later only)
-
-.L0:
-#if XCHAL_HAVE_DEBUG
- break 1, 15 // give control to debugger
-#elif XCHAL_HAVE_HALT
- halt
-#endif
- j .L0
-
- .size _start, . - _start
-
-
-// Local Variables:
-// mode:fundamental
-// comment-start: "// "
-// comment-start-skip: "// *"
-// End:
projects / open-ath9k-htc-firmware.git / blobdiff