[PATCH] MicroBlaze: Update software breakpoint machine code as per MicroBlaze ISA

[Gopi Kumar Bulusu <gopi@sankhya.com>]

[-- Attachment #1.1: Type: text/plain, Size: 537 bytes --]

namaskaaram,

The macro MICROBLAZE_BREAKPOINT is set to an instruction opcode that does
not meet the criteria for software breakpoint instruction as set forth in
the AMD MicroBlaze ISA. This patch  addresses the problem.

This simple patch concludes a series of patches that add AMD MicroBlaze
gdbserver target support for GNU/Linux.

Updated NEWS to include MicroBlaze gdbserver target.

Build/Test - tested by building microblazeel-linux-gdb and verifying that
software breakpoint works
using gdbserver as target.

dhanyavaadaaha
gopi

[-- Attachment #1.2: Type: text/html, Size: 910 bytes --]

[-- Attachment #2: 0001-MicroBlaze-Update-software-breakpoint-machine-code-a.patch --]
[-- Type: text/x-patch, Size: 1665 bytes --]

From a85980e98bf614fe7de60ddc8479d24f65009572 Mon Sep 17 00:00:00 2001
From: Gopi Kumar Bulusu <gopi@sankhya.com>
Date: Tue, 9 Sep 2025 12:00:11 +0530
Subject: [PATCH] MicroBlaze: Update software breakpoint machine code as per
 MicroBlaze ISA

This patch updates breakpoint instruction machine code to be inline
with the specification in MicroBlaze ISA [1]

* gdb/microblaze-tdep.h : Update MICROBLAZE_BREAKPOINT
* gdb/NEWS : Add MicroBlaze gdbserver target

[1] https://docs.amd.com/r/en-US/ug984-vivado-microblaze-ref/brki

Signed-off-by: David Holsgrove <david.holsgrove@petalogix.com>
Signed-off-by: Nathan Rossi <nathan.rossi@petalogix.com>
Signed-off-by: Mahesh Bodapati <mbodapat@xilinx.com>
Signed-off-by: Gopi Kumar Bulusu <gopi@sankhya.com>
---
 gdb/NEWS              | 4 ++++
 gdb/microblaze-tdep.h | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/gdb/NEWS b/gdb/NEWS
index 48f7bfabea7..36065ec1943 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,10 @@
 
 *** Changes since GDB 17
 
+* New targets
+
+GNU/Linux/MicroBlaze (gdbserver) microblazeel-*linux*
+
 *** Changes in GDB 17
 
 * Debugging Linux programs that use x86-64 or x86-64 with 32-bit pointer
diff --git a/gdb/microblaze-tdep.h b/gdb/microblaze-tdep.h
index b2fb5e7fcb9..852c9ebbafe 100644
--- a/gdb/microblaze-tdep.h
+++ b/gdb/microblaze-tdep.h
@@ -118,6 +118,6 @@ struct microblaze_frame_cache
 
 /* MICROBLAZE_BREAKPOINT defines the breakpoint that should be used.
    Only used for native debugging.  */
-#define MICROBLAZE_BREAKPOINT {0xb9, 0xcc, 0x00, 0x60}
+#define MICROBLAZE_BREAKPOINT {0xba, 0x0c, 0x00, 0x18}
 
 #endif /* GDB_MICROBLAZE_TDEP_H */
-- 
2.47.1