|author||Karel Gardas <firstname.lastname@example.org>||2020-09-19 20:12:45 +0000|
|committer||Gedare Bloom <email@example.com>||2020-09-21 11:29:52 -0600|
pc386 BSP: add runtime options for debugging and move few lines around for better context.
Diffstat (limited to '')
1 files changed, 27 insertions, 5 deletions
diff --git a/user/bsps/bsps-i386.rst b/user/bsps/bsps-i386.rst
index 91908f1..42f3ebf 100644
@@ -140,6 +140,9 @@ inside the Qemu emulator.
specifies target device for printk/getk
calls. E.g. ``--printk=/dev/vgacons``
+If the specified console device is not present then suitable fallback
+device is selected based on the device order specified in `Console Drivers`.
.. option:: --video=<mode>
specifies required video mode. The options applies only to
@@ -157,12 +160,27 @@ inside the Qemu emulator.
disables usage of COM1 thorough COM4.
-If the specified console device is not present then suitable fallback
-device is selected based on the device order specified in `Console Drivers`.
+.. option:: --gdb=<dev>
-PCI-based UART devices are named ``/dev/pcicom<number>`` as they are
-probed and found. The numbers sequence starts with 1. E.g. first PCI
-UART device found is accessible with ``/dev/pcicom1`` name.
+ specifies UART device for communication between BSP's
+ GDB stub and GDB running on a host system. Option accepts device
+ and baud rate like the ``--console`` option above.
+ E.g. ``--gdb=/dev/com2,115200`` instructs BSP to use COM2 device
+ for GDB stub/host communication with the speed of 115200 bauds.
+ .. note:: default GDB stub/host communication speed and other
+ communication properties are same like for console over
+ UART. E.g. 9600 baud rate, 8 data bits, no parity
+ and 1 stop bit.
+.. option:: --gdb-break
+ halts BSP execution at a break point in the BSP initialization code
+ and waits for GDB connection.
+.. option:: --gdb-remote-debug
+ outputs the GDB remote protocol data to printk.
Testing with Qemu
@@ -321,6 +339,10 @@ following order of priority:
- COM1 thorough COM4
- Any COM devices on the PCI bus including IO and memory mapped
+PCI-based UART devices are named ``/dev/pcicom<number>`` as they are
+probed and found. The numbers sequence starts with 1. E.g. first PCI
+UART device found is accessible with ``/dev/pcicom1`` name.
Besides supporting generic devices above, the BSP also support
specific UART chips. The drivers for those are not initialized
automatically, but requires initialization from the application code: