| <html lang="en"> |
| <head> |
| <title>Memory Map Format - Debugging with GDB</title> |
| <meta http-equiv="Content-Type" content="text/html"> |
| <meta name="description" content="Debugging with GDB"> |
| <meta name="generator" content="makeinfo 4.13"> |
| <link title="Top" rel="start" href="index.html#Top"> |
| <link rel="up" href="Remote-Protocol.html#Remote-Protocol" title="Remote Protocol"> |
| <link rel="prev" href="Library-List-Format-for-SVR4-Targets.html#Library-List-Format-for-SVR4-Targets" title="Library List Format for SVR4 Targets"> |
| <link rel="next" href="Thread-List-Format.html#Thread-List-Format" title="Thread List Format"> |
| <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> |
| <!-- |
| Copyright (C) 1988-2019 Free Software Foundation, Inc. |
| |
| Permission is granted to copy, distribute and/or modify this document |
| under the terms of the GNU Free Documentation License, Version 1.3 or |
| any later version published by the Free Software Foundation; with the |
| Invariant Sections being ``Free Software'' and ``Free Software Needs |
| Free Documentation'', with the Front-Cover Texts being ``A GNU Manual,'' |
| and with the Back-Cover Texts as in (a) below. |
| |
| (a) The FSF's Back-Cover Text is: ``You are free to copy and modify |
| this GNU Manual. Buying copies from GNU Press supports the FSF in |
| developing GNU and promoting software freedom.'' |
| --> |
| <meta http-equiv="Content-Style-Type" content="text/css"> |
| <style type="text/css"><!-- |
| pre.display { font-family:inherit } |
| pre.format { font-family:inherit } |
| pre.smalldisplay { font-family:inherit; font-size:smaller } |
| pre.smallformat { font-family:inherit; font-size:smaller } |
| pre.smallexample { font-size:smaller } |
| pre.smalllisp { font-size:smaller } |
| span.sc { font-variant:small-caps } |
| span.roman { font-family:serif; font-weight:normal; } |
| span.sansserif { font-family:sans-serif; font-weight:normal; } |
| --></style> |
| </head> |
| <body> |
| <div class="node"> |
| <a name="Memory-Map-Format"></a> |
| <p> |
| Next: <a rel="next" accesskey="n" href="Thread-List-Format.html#Thread-List-Format">Thread List Format</a>, |
| Previous: <a rel="previous" accesskey="p" href="Library-List-Format-for-SVR4-Targets.html#Library-List-Format-for-SVR4-Targets">Library List Format for SVR4 Targets</a>, |
| Up: <a rel="up" accesskey="u" href="Remote-Protocol.html#Remote-Protocol">Remote Protocol</a> |
| <hr> |
| </div> |
| |
| <h3 class="section">E.16 Memory Map Format</h3> |
| |
| <p><a name="index-memory-map-format-3633"></a> |
| To be able to write into flash memory, <span class="sc">gdb</span> needs to obtain a |
| memory map from the target. This section describes the format of the |
| memory map. |
| |
| <p>The memory map is obtained using the ‘<samp><span class="samp">qXfer:memory-map:read</span></samp>’ |
| (see <a href="qXfer-memory-map-read.html#qXfer-memory-map-read">qXfer memory map read</a>) packet and is an XML document that |
| lists memory regions. |
| |
| <p><span class="sc">gdb</span> must be linked with the Expat library to support XML |
| memory maps. See <a href="Expat.html#Expat">Expat</a>. |
| |
| <p>The top-level structure of the document is shown below: |
| |
| <pre class="smallexample"> <?xml version="1.0"?> |
| <!DOCTYPE memory-map |
| PUBLIC "+//IDN gnu.org//DTD GDB Memory Map V1.0//EN" |
| "http://sourceware.org/gdb/gdb-memory-map.dtd"> |
| <memory-map> |
| region... |
| </memory-map> |
| </pre> |
| <p>Each region can be either: |
| |
| <ul> |
| <li>A region of RAM starting at <var>addr</var> and extending for <var>length</var> |
| bytes from there: |
| |
| <pre class="smallexample"> <memory type="ram" start="<var>addr</var>" length="<var>length</var>"/> |
| </pre> |
| <li>A region of read-only memory: |
| |
| <pre class="smallexample"> <memory type="rom" start="<var>addr</var>" length="<var>length</var>"/> |
| </pre> |
| <li>A region of flash memory, with erasure blocks <var>blocksize</var> |
| bytes in length: |
| |
| <pre class="smallexample"> <memory type="flash" start="<var>addr</var>" length="<var>length</var>"> |
| <property name="blocksize"><var>blocksize</var></property> |
| </memory> |
| </pre> |
| </ul> |
| |
| <p>Regions must not overlap. <span class="sc">gdb</span> assumes that areas of memory not covered |
| by the memory map are RAM, and uses the ordinary ‘<samp><span class="samp">M</span></samp>’ and ‘<samp><span class="samp">X</span></samp>’ |
| packets to write to addresses in such ranges. |
| |
| <p>The formal DTD for memory map format is given below: |
| |
| <pre class="smallexample"> <!-- ................................................... --> |
| <!-- Memory Map XML DTD ................................ --> |
| <!-- File: memory-map.dtd .............................. --> |
| <!-- .................................... .............. --> |
| <!-- memory-map.dtd --> |
| <!-- memory-map: Root element with versioning --> |
| <!ELEMENT memory-map (memory)*> |
| <!ATTLIST memory-map version CDATA #FIXED "1.0.0"> |
| <!ELEMENT memory (property)*> |
| <!-- memory: Specifies a memory region, |
| and its type, or device. --> |
| <!ATTLIST memory type (ram|rom|flash) #REQUIRED |
| start CDATA #REQUIRED |
| length CDATA #REQUIRED> |
| <!-- property: Generic attribute tag --> |
| <!ELEMENT property (#PCDATA | property)*> |
| <!ATTLIST property name (blocksize) #REQUIRED> |
| </pre> |
| </body></html> |
| |