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Diffstat (limited to 'libgloss/msp430/crt_move_highdata.S')
-rw-r--r-- | libgloss/msp430/crt_move_highdata.S | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/libgloss/msp430/crt_move_highdata.S b/libgloss/msp430/crt_move_highdata.S new file mode 100644 index 0000000..b969549 --- /dev/null +++ b/libgloss/msp430/crt_move_highdata.S @@ -0,0 +1,71 @@ +/* Copyright (c) 2012-2015 Red Hat Incorporated. + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + + The name of Red Hat Incorporated may not be used to endorse + or promote products derived from this software without specific + prior written permission. + + This software is provided by the copyright holders and contributors + "AS IS" and any express or implied warranties, including, but not + limited to, the implied warranties of merchantability and fitness for + a particular purpose are disclaimed. In no event shall Red Hat + incorporated be liable for any direct, indirect, incidental, special, + exemplary, or consequential damages (including, but not limited to, + procurement of substitute goods or services; loss of use, data, or + profits; or business interruption) however caused and on any theory of + liability, whether in contract, strict liability, or tort (including + negligence or otherwise) arising in any way out of the use of this + software, even if advised of the possibility of such damage. */ + +#ifdef __MSP430X_LARGE__ + +#include "memmodel.h" + +;; This function is responsible for making sure that the +;; contents of the .upper.data section have their correct startup values. +;; If a copy of the .upper.data section is stored in ROM then this means +;; copying the contents into HIFRAM. If a copy of .upper.data is stored in a +;; shadow section in HIFRAM then this means copying from the shadow section +;; into the real section. + +START_CRT_FUNC 0400 move_highdata + ;; __rom_highdatacopysize may be zero. Test this first because + ;; its value may come from the weak definitions above and we do + ;; not want to access the memory at address 0 pointed to by the + ;; weak definition of __upper_data_init. + mov.w #__rom_highdatacopysize, R14 + cmp.w #0, R14 + jeq 3f + + /* Test our status word. */ + cmpx.w #0, &__upper_data_init + jeq 1f + /* Status word is non-zero - copy from shadow into upper. */ + mov_ #__high_datastart, R12 + mov_ #__rom_highdatastart, R13 + jmp 2f + +1: /* Status word is zero. Copy from upper to shadow and change status word. */ + movx.w #1, &__upper_data_init + mov_ #__rom_highdatastart, R12 + mov_ #__high_datastart, R13 + +2: ;; __rom_highdatacopysize may be zero. memmove should cope. + mov.w #__rom_highdatacopysize, R14 + + call_ #memmove +3: +END_CRT_FUNC move_highdata + +#endif /* __MSP430X_LARGE__ */ |