From a976ed3ffdede7f64c89ac235d0154d048981b5f Mon Sep 17 00:00:00 2001
From: KONRAD Frederic
Date: Thu, 30 Apr 2020 20:01:22 +0100
Subject: target/m68k: fix gdb for m68xxx

Currently "cf-core.xml" is sent to GDB when using any m68k flavor.  Thing is
it uses the "org.gnu.gdb.coldfire.core" feature name and gdb 8.3 then expects
a coldfire FPU instead of the default m68881 FPU.

This is not OK because the m68881 floats registers are 96 bits wide so it
crashes GDB with the following error message:

(gdb) target remote localhost:7960
Remote debugging using localhost:7960
warning: Register "fp0" has an unsupported size (96 bits)
warning: Register "fp1" has an unsupported size (96 bits)
...
Remote 'g' packet reply is too long (expected 148 bytes, got 180 bytes):    \
  00000000000[...]0000

With this patch: qemu-system-m68k -M none -cpu m68020 -s -S

(gdb) tar rem :1234
Remote debugging using :1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x00000000 in ?? ()
(gdb) p $fp0
$1 = nan(0xffffffffffffffff)

Signed-off-by: KONRAD Frederic <frederic.konrad@adacore.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <1588094279-17913-3-git-send-email-frederic.konrad@adacore.com>
Message-Id: <20200430190122.4592-10-alex.bennee@linaro.org>
---
 gdb-xml/m68k-core.xml | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 gdb-xml/m68k-core.xml

(limited to 'gdb-xml')

diff --git a/gdb-xml/m68k-core.xml b/gdb-xml/m68k-core.xml
new file mode 100644
index 0000000000..5b092d26de
--- /dev/null
+++ b/gdb-xml/m68k-core.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0"?>
+<!-- Copyright (C) 2008 Free Software Foundation, Inc.
+
+     Copying and distribution of this file, with or without modification,
+     are permitted in any medium without royalty provided the copyright
+     notice and this notice are preserved.  -->
+<!DOCTYPE feature SYSTEM "gdb-target.dtd">
+<feature name="org.gnu.gdb.m68k.core">
+  <reg name="d0" bitsize="32"/>
+  <reg name="d1" bitsize="32"/>
+  <reg name="d2" bitsize="32"/>
+  <reg name="d3" bitsize="32"/>
+  <reg name="d4" bitsize="32"/>
+  <reg name="d5" bitsize="32"/>
+  <reg name="d6" bitsize="32"/>
+  <reg name="d7" bitsize="32"/>
+  <reg name="a0" bitsize="32" type="data_ptr"/>
+  <reg name="a1" bitsize="32" type="data_ptr"/>
+  <reg name="a2" bitsize="32" type="data_ptr"/>
+  <reg name="a3" bitsize="32" type="data_ptr"/>
+  <reg name="a4" bitsize="32" type="data_ptr"/>
+  <reg name="a5" bitsize="32" type="data_ptr"/>
+  <reg name="fp" bitsize="32" type="data_ptr"/>
+  <reg name="sp" bitsize="32" type="data_ptr"/>
+
+  <reg name="ps" bitsize="32"/>
+  <reg name="pc" bitsize="32" type="code_ptr"/>
+
+</feature>
-- 
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