DOC: change PCI uart description from mmio to bdf

HV code changed to configure PCI uart mmio@ to bdf@,
so change its description to match it.

Tracked-On: #2031
Signed-off-by: Minggui Cao <minggui.cao@intel.com>

doc/getting-started/apl-nuc.rst

@@ -177,7 +177,8 @@ partition. Follow these steps:
       whether it should be disabled. There are three forms for this parameter:
 
       #. ``uart=disabled``: this disables the serial port completely
-      #. ``uart=mmio@<MMIO address>``: this sets the serial port MMIO address
+      #. ``uart=bdf@<BDF value>``:  this sets the PCI serial port based on its BDF.
+         For example, use ``bdf@0:18.2`` for a BDF of 0:18.2 ttyS2.
       #. ``uart=port@<port address>``: this sets the serial port address
 
    Here is a more complete example of how to configure the EFI firmware to load the ACRN

doc/getting-started/up2.rst

@@ -75,21 +75,21 @@ You will need to keep these in mind in a few places:
   .. code-block:: none
 
      # efibootmgr -c -l "\EFI\acrn\acrn.efi" -d /dev/mmcblk0 -p 1 -L "ACRN Hypervisor" \
-         -u "bootloader=\EFI\org.clearlinux\bootloaderx64.efi uart=mmio@0x9141e000"
+         -u "bootloader=\EFI\org.clearlinux\bootloaderx64.efi uart=bdf@0:18.1"
 
 UP2 serial port setting
 =======================
 
-The serial port in the 40-pin HAT connector is located at ``MMIO 0x0x9141e000``.
-You can check this from the ``dmesg`` output from the initial Clearlinux installation.
+The serial port in the 40-pin HAT connector is located at ``serial PCI BDF 0:18.1``.
+You can check this from the ``lspci`` output from the initial Clearlinux installation.
 
 .. code-block:: none
 
-   # dmesg | grep dw-apb-uart
-   [2.150689] dw-apb-uart.8: ttyS1 at MMIO 0x91420000 (irq = 4, base_baud = 115200) is a 16550A
-   [2.152072] dw-apb-uart.9: ttyS2 at MMIO 0x9141e000 (irq = 5, base_baud = 115200) is a 16550A
+   # lspci | grep UART
+   00:18.0 . Series HSUART Controller #1 (rev 0b)
+   00:18.1 . Series HSUART Controller #2 (rev 0b)
 
-The second entry associated with ``dw-apb-uart.9`` is the one on the 40-pin HAT connector.
+The second entry associated with ``00:18.1`` is the one on the 40-pin HAT connector.
 
 UP2 block device
 ================

doc/tutorials/using_partition_mode_on_up2.rst

@@ -106,11 +106,11 @@ Enable partition mode in ACRN hypervisor
    .. code-block:: none
      :emphasize-lines: 1
 
-     $ dmesg | grep ttyS
-     [   10.552369] dw-apb-uart.8: ttyS4 at MMIO 0x91524000 (irq = 4, base_baud = 115200) is a 16550A
-     [   10.552568] serial serial0: tty port ttyS4 registered
-     [   10.572344] dw-apb-uart.9: ttyS5 at MMIO 0x91522000 (irq = 5, base_baud = 115200) is a 16550A
-     [   10.572545] serial serial1: tty port ttyS5 registered
+     $ sudo lspci | grep UART
+     00:18.0 . Series HSUART Controller #1 (rev 0b)
+     00:18.1 . Series HSUART Controller #2 (rev 0b)
+
+     The second with ``00:18.1`` is the one on the 40-pin expansion connector.
 
    The following command prints detailed information about all PCI buses
    and devices in the system. Look up the PCI BAR addresses of the SATA
@@ -153,7 +153,7 @@ Enable partition mode in ACRN hypervisor
      $ make menuconfig
 
    Set the ``Hypervisor mode`` option to ``Partition mode``, and depending
-   on the serial port you are using, enter its MMIO address to the configuration
+   on the serial port you are using, enter its BDF to the configuration
    menu as shown in this screenshot. Finally, save the configuration.
 
    .. figure:: images/menuconfig-partition-mode.png
@@ -347,8 +347,8 @@ Switch between privileged VMs
 *****************************
 
 Connect the serial port on the UP2 board to the development workstation.
-If you set the MMIO address of the serial port right while building the
-ACRN hypervisor, you should see the output from the ACRN serial console as below.
+If you set the BDF of the serial port right while building the ACRN hypervisor,
+you should see the output from the ACRN serial console as below.
 You could then log in to the privileged VMs by ``sos_console`` command,
 and press :kbd:`CTRL+Space` keys to return to the ACRN serial console.