When scanning for the Serial Port in the device
tree, the length and value parameters to ScanMem8()
are not in the right order. This results in the
serial port not being detected if the chosen node
in the device tree has additional elements.
Therefore, pass the parameters to ScanMem8() in the
correct order to fix this issue.
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
In an effort to clean the documentation of the above
package, remove duplicated words.
Cc: Sami Mujawar <Sami.Mujawar@arm.com>
Cc: Alexei Fedorov <Alexei.Fedorov@arm.com>
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
The Microsoft Debug Port Table 2 (DBG2), the Serial Port Console
Redirector (SPCR) table are mandatory tables required for booting
a standards-based operating system. The DBG2 table is used by the
OS debugger while the SPCR table is used to configure the serial
terminal. Additionally, the serial ports available on a platform
for generic use also need to be described in DSDT/SSDT for an OS
to be able to use the serial ports.
The Arm Base System Architecture 1.0 specification a lists of
supported serial port hardware for Arm Platforms. This list
includes the following serial port UARTs:
- SBSA/Generic UART
- a fully 16550 compatible UART.
Along, with these the PL011 UART is the most commonly used serial
port hardware on Arm platforms.
The serial port hardware information is described in the platform
Device Tree, the bindings for which can be found at:
- linux/Documentation/devicetree/bindings/serial/serial.yaml
- linux/Documentation/devicetree/bindings/serial/8250.txt
- linux/Documentation/devicetree/bindings/serial/arm_sbsa_uart.txt
- linux/Documentation/devicetree/bindings/serial/pl011.yaml
The FdtHwInfoParser implements a Serial Port Parser that parses
the platform Device Tree to create CM_ARM_SERIAL_PORT_INFO objects
with the following IDs:
- EArmObjSerialConsolePortInfo (for use by SPCR)
- EArmObjSerialDebugPortInfo (for use by DBG2)
- EArmObjSerialPortInfo (for use as generic Serial Ports)
The Serial Port for use by SPCR is selected by parsing the Device
Tree for the '/chosen' node with the 'stdout-path' property. The
next Serial Port is selected for use as the Debug Serial Port and
the remaining serial ports are used as generic serial ports.
The CM_ARM_SERIAL_PORT_INFO objects are encapsulated in Configuration
Manager descriptor objects with the respective IDs and are added to
the platform information repository.
The platform Configuration Manager can then utilise this information
when generating the DBG2, SPCR and the SSDT serial port tables.
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Sami Mujawar
Pierre Gondois