uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(16)：使用head.s做为入口点
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http://blog.csdn.net/lights_joy/
本文适用于
ADI bf561 DSP
uclinux-2008r1.5-rc3
Visual DSP++ 5.0(update 5)
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创建uclinux工程时，默认的入口是uclinux _basiccrt.s，而我们需要用head.s做为入口，因此需要修改ldf文件中的相关定义。
在uclinux.ldf文件中有这么几行：
$OBJECTS_CORE_A =
/*$VDSG<insert-user-objects-for-coreA-beginning> */
/* Text inserted between these $VDSG comments will be preserved */
/*$VDSG<insert-user-objects-for-coreA-beginning> */
"uclinux_basiccrt.doj"
, RT_LIB_NAME(profile561)
, $COMMAND_LINE_OBJECTS {!DualCoreMem("CoreB")}
, "cplbtab<?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" /><chmetcnv w:st="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="561" unitname="a">561a</chmetcnv>.doj"
, RT_OBJ_NAME(crtn561)
在此先删除uclinux _basiccrt.doj，于是就变成了
$OBJECTS_CORE_A =
/*$VDSG<insert-user-objects-for-coreA-beginning> */
/* Text inserted between these $VDSG comments will be preserved */
/*$VDSG<insert-user-objects-for-coreA-beginning> */
, RT_LIB_NAME(profile561)
, $COMMAND_LINE_OBJECTS {!DualCoreMem("CoreB")}
, "cplbtab<chmetcnv w:st="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="561" unitname="a">561a</chmetcnv>.doj"
, RT_OBJ_NAME(crtn561)
此外，还要在processor p0中保留__start的位置。在默认生成的LDF文件中，是这样的：
RESOLVE(start, 0xFFA00000)
KEEP(start,_main)
我们将其指向head.s中的__start，修改后变成：
RESOLVE(__start, 0xFFA00000)
KEEP(__start,_main)
当然，这样修改后会造成一系列的错误：
[Error li1021] The following symbols referenced in processor 'p0' could not be resolved:
'__bss_start [___bss_start]' referenced from 'corea.dlb[head.doj]'
'__bss_stop [___bss_stop]' referenced from 'corea.dlb[head.doj]'
'_sdata [__sdata]' referenced from 'corea.dlb[head.doj]'
'_stext [__stext]' referenced from 'corea.dlb[head.doj]'
'bf53x_relocate_l1_mem [_bf53x_relocate_l1_mem]' referenced from 'corea.dlb[head.doj]'
'cmdline_init [_cmdline_init]' referenced from 'corea.dlb[head.doj]'
'init_pda [_init_pda]' referenced from 'corea.dlb[head.doj]'
'init_thread_union [_init_thread_union]' referenced from 'corea.dlb[head.doj]'
'start_kernel [_start_kernel]' referenced from 'corea.dlb[head.doj]'
没关系，这正好说明我们的head.s已经开始起作用了。
1 参考资料
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(1)：前言(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(2)：代码注释(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(3)：vdsp项目创建(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(4)：目录差异(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(5)：'bf561.h'的问题(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(6)：CONFIG_BFIN_KERNEL_CLOCK(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(7)：CONFIG_MEM_MT48LC16M16A2TG_75(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(8)：CONFIG_CLKIN_HZ(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(9)：CONFIG_MEM_SIZE(<chsdate w:st="on" year="2009" month="1" day="12" islunardate="False" isrocdate="False">2009-1-12</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(10)：CONFIG_FLASH_SPEED_BTT(<chsdate w:st="on" year="2009" month="1" day="13" islunardate="False" isrocdate="False">2009-1-13</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(11)：__INIT(<chsdate w:st="on" year="2009" month="1" day="13" islunardate="False" isrocdate="False">2009-1-13</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(12)：trace_buffer_init(<chsdate w:st="on" year="2009" month="1" day="13" islunardate="False" isrocdate="False">2009-1-13</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(13)：ENDPROC(<chsdate w:st="on" year="2009" month="1" day="13" islunardate="False" isrocdate="False">2009-1-13</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(14)：__FINIT(<chsdate w:st="on" year="2009" month="1" day="13" islunardate="False" isrocdate="False">2009-1-13</chsdate>)
uclinux-2008R1.5-RC3(bf561)到VDSP5的移植(15)：CONFIG_BANK_x(<chsdate w:st="on" year="2009" month="1" day="13" islunardate="False" isrocdate="False">2009-1-13</chsdate>)