1 | <?xml version="1.0" encoding="ISO-8859-1"?> |
---|
2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" |
---|
3 | "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ |
---|
4 | <!ENTITY % general-entities SYSTEM "../../general.ent"> |
---|
5 | %general-entities; |
---|
6 | ]> |
---|
7 | |
---|
8 | <sect1 id="ch-system-abi"> |
---|
9 | <?dbhtml filename="abi.html"?> |
---|
10 | |
---|
11 | <title>ABI Variables</title> |
---|
12 | |
---|
13 | <para os="a">On the ARM architecture, there are two major ABI types to choose |
---|
14 | from: EABI and OABI. There is also a Thumb ABI and an Intel IWMMX specific |
---|
15 | ABI but these are generally not recommended for most uses.</para> |
---|
16 | |
---|
17 | <para os="b">The EABI (Embedded ABI) is newer and supports additional |
---|
18 | features, faster software floating point operations, and Thumb interworking, |
---|
19 | but is only compatible with ARMv4t and newer cores. The EABI has |
---|
20 | sub-ABIs of: aapcs-linux and aapcs. aapcs-linux has standard Linux 4 byte |
---|
21 | enums while aapcs has variable length enums. aapcs-linux is recommended over |
---|
22 | aapcs.</para> |
---|
23 | |
---|
24 | <para os="c">The OABI (old ABI) is called apcs-gnu and supports ARMv4 and |
---|
25 | older cores. Generally the OABI is not used by modern ARM processors.</para> |
---|
26 | |
---|
27 | <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" |
---|
28 | href="../common/abi.xml" |
---|
29 | xpointer="xpointer(//*[@os='a'])"/> |
---|
30 | |
---|
31 | <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" |
---|
32 | href="../common/abi.xml" |
---|
33 | xpointer="xpointer(//*[@os='b'])"/> |
---|
34 | |
---|
35 | <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" |
---|
36 | href="../common/abi.xml" |
---|
37 | xpointer="xpointer(//*[@os='c'])"/> |
---|
38 | |
---|
39 | <table> |
---|
40 | <title>List of Build Variables</title> |
---|
41 | <?dbfo table-width="3in" ?> |
---|
42 | |
---|
43 | <tgroup cols="2"> |
---|
44 | |
---|
45 | <colspec colnum="1" colwidth="1.5in" colname="ABI to Select"/> |
---|
46 | <colspec colnum="2" colwidth="1.5in" colname="Variable Value"/> |
---|
47 | <colspec colnum="3" colwidth="2in" colname="Note"/> |
---|
48 | |
---|
49 | <thead> |
---|
50 | <row> |
---|
51 | <entry>ABI</entry> |
---|
52 | <entry>CLFS_ABI=Value</entry> |
---|
53 | <entry>Note</entry> |
---|
54 | </row> |
---|
55 | </thead> |
---|
56 | |
---|
57 | <tbody> |
---|
58 | <row> |
---|
59 | <entry>aapcs-linux</entry> |
---|
60 | <entry>aapcs-linux</entry> |
---|
61 | <entry>Recommended for EABI. Standard Linux 32 bit (int) enums</entry> |
---|
62 | </row> |
---|
63 | <row> |
---|
64 | <entry>apcs-gnu</entry> |
---|
65 | <entry>apcs-gnu</entry> |
---|
66 | <entry>Recommended for OABI</entry> |
---|
67 | </row> |
---|
68 | <row> |
---|
69 | <entry>atpcs</entry> |
---|
70 | <entry>atpcs</entry> |
---|
71 | <entry>Thumb ABI</entry> |
---|
72 | </row> |
---|
73 | <row> |
---|
74 | <entry>aapcs</entry> |
---|
75 | <entry>aapcs</entry> |
---|
76 | <entry>EABI w/ variable size enums</entry> |
---|
77 | </row> |
---|
78 | <row> |
---|
79 | <entry>iwmmxt</entry> |
---|
80 | <entry>iwmmxt</entry> |
---|
81 | <entry>Supports Intel XScale MMX extensions</entry> |
---|
82 | </row> |
---|
83 | </tbody> |
---|
84 | |
---|
85 | </tgroup> |
---|
86 | |
---|
87 | </table> |
---|
88 | |
---|
89 | </sect1> |
---|
90 | |
---|