[PATCH] Add baseboard for PRU simulator

[Dimitar Dimitrov]

I'm running [1] PRU regression tests using this baseboard definition and
mainline Binutils, GCC, Newlib and GNU Simulator.

[1] https://github.com/dinuxbg/gnupru/blob/master/testing/buildbot-pru.sh

ChangeLog:

        * Makefile.am: Add pru-sim.exp.
        * Makefile.in: Ditto.
        * baseboards/pru-sim.exp: New file.

Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>
---
 Makefile.am            |  1 +
 Makefile.in            |  1 +
 baseboards/pru-sim.exp | 60 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 62 insertions(+)
 create mode 100644 baseboards/pru-sim.exp

diff --git a/Makefile.am b/Makefile.am
index 29fa4f4..dfbfd40 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -130,6 +130,7 @@ baseboard_DATA = \
        baseboards/pi.exp \
        baseboards/powerpc-sim.exp \
        baseboards/powerpcle-sim.exp \
+       baseboards/pru-sim.exp \
        baseboards/qemu.exp \
        baseboards/riscv-sim.exp \
        baseboards/rx-sim.exp \
diff --git a/Makefile.in b/Makefile.in
index ef6ba88..8d5d55b 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -460,6 +460,7 @@ baseboard_DATA = \
        baseboards/pi.exp \
        baseboards/powerpc-sim.exp \
        baseboards/powerpcle-sim.exp \
+       baseboards/pru-sim.exp \
        baseboards/qemu.exp \
        baseboards/riscv-sim.exp \
        baseboards/rx-sim.exp \
diff --git a/baseboards/pru-sim.exp b/baseboards/pru-sim.exp
new file mode 100644
index 0000000..40c597e
--- /dev/null
+++ b/baseboards/pru-sim.exp
@@ -0,0 +1,60 @@
+# Copyright (C) 1997-2020 Free Software Foundation, Inc.
+#
+# This file is part of DejaGnu.
+#
+# DejaGnu is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# DejaGnu is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with DejaGnu; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
+
+# This is a list of toolchains that are supported on this board.
+set_board_info target_install {pru-elf}
+
+# Load the generic configuration for this board, This will define a basic
+# set of routines needed by the tool to communicate with the board.
+load_generic_config "sim"
+
+# basic-sim.exp is a basic description for the standard Cygnus simulator.
+load_base_board_description "basic-sim"
+
+# The name of the simulator is "pru".
+setup_sim pru
+
+# No multilib flags needed by default.
+process_multilib_options ""
+
+# The compiler used to build for this board. This has *nothing* to do
+# with what compiler is tested if we're testing gcc.
+set_board_info compiler  "[find_gcc]"
+
+# PRU arguments are mostly passed in registers. But GCC regression tests
+# are written with other machines in mind, so the builtin_apply's
+# aruments stack size is non-zero. On top of that, the stack top for
+# PRU's main is very close to the end of SRAM. Close enough that the
+# spurious "stack copy" reads outside of the DRAM area, causing a
+# simulator abort. For example, see how builtin-apply-3.c copies 16
+# bytes from the arguments stack, while PRU has passed all of its
+# arguments in registers.
+#
+# Temporary solution is to add a few bytes of "guard" space, so that
+# existing GCC testcases can be executed successfully. Hence set the
+# stack top a few bytes below the simulator's DRAM end.
+set workaround_ldflags "-Wl,--defsym=_stack_top=0x3fff800"
+
+set_board_info cflags  "-mmcu=sim [libgloss_include_flags] 
[newlib_include_flags]"
+set_board_info ldflags  "[libgloss_link_flags] [newlib_link_flags] 
$workaround_ldflags"
+
+# No support for signals on this target.
+set_board_info gdb,nosignals 1
+
+# Low-end workstations might require even larger timeouts.
+set timeout 120
-- 
2.20.1