Document UART memmap offset

Validated on Sakura, Sunflower, Marigold, Lotus.
Others are from coreboot sourcecode, most likely correct.

Signed-off-by: Daniel Schaefer <dhs@frame.work>

Author: JohnAZoidberg

README.md

@@ -337,21 +337,26 @@ console with no other graphics or networking running.
 
 #### Hardware Support
 
-| Codename  | Type-C Port  | Commandline parameter     | Function | Flipped? | BIOS Ver |
-|-----------|--------------|---------------------------|----------|----------|----------|
-| Dogwood   | Top Back     | `console=ttyS4,115200`    | Full TTY | No       | 3.00+    |
-| Lotus     | Middle Right |                           |          |          | N/A      |
-| Tulip     | Middle Right | `console=ttyS4,115200`    | Full TTY | Yes      | 3.00+    |
-| Lilac     | Back Left    | `console=ttyS4,115200`    | Full TTY | No       | 3.00+    |
-| Azalea    | Front Right  |                           |          |          | N/A      |
-| TGL       | N/A          |                           |          |          |          |
-| ADL/Iris  | Back Left    | `console=ttyS0,115200n8`  |          |          | N/A      |
-| Marigold  | Front Right  | `console=ttyS0,115200n8`  |          | No       | N/A      |
-| Sakura    | Front Right  | `console=ttyS0,115200n8`  | Full TTY | No       | 3.00+    |
-| Sunflower | Front Right  | `console=uart,0xfe03e000` | Log only | No       | 3.00+    |
+| Codename  | Type-C Port  | Commandline parameter     | Function | Flipped? | BIOS Ver | Memmap       |
+|-----------|--------------|---------------------------|----------|----------|----------|--------------|
+| Dogwood   | Top Back     | `console=ttyS4,115200`    | Full TTY | No       | 3.00+    |              |
+| Lotus     | Middle Right |                           |          |          | N/A      | `0xfedc9000` |
+| Tulip     | Middle Right | `console=ttyS4,115200`    | Full TTY | Yes      | 3.00+    |              |
+| Lilac     | Back Left    | `console=ttyS4,115200`    | Full TTY | No       | 3.00+    |              |
+| Azalea    | Front Right  |                           |          |          | N/A      | `0xfedc9000` |
+| TGL       | N/A          |                           |          |          |          | `0xfe03e000` |
+| ADL/Iris  | Back Left    | `console=ttyS0,115200n8`  |          |          | N/A      | `0xfe03e000` |
+| Marigold  | Front Right  | `console=ttyS0,115200n8`  |          | No       | N/A      | `0xfe036000` |
+| Sakura    | Front Right  | `console=ttyS0,115200n8`  | Full TTY | No       | 3.00+    | `0xfe02c000` |
+| Sunflower | Front Right  | `console=uart,0xfe03e000` | Log only | No       | 3.00+    | `0xfe03e000` |
 
 ADL, Iris, Azalea, Lotus, Marigold have support in hardware but the BIOS does not expose it to the OS.
 
+Some platforms have it enabled in BIOS and exposed through ACPI to the OS,
+meaning no detailed configuration is necessary, just telling the OS to use e.g.
+`ttyS0`. Other platforms, e.g. Sunflower, need custom configuration to tell the
+OS about the memory map offset.
+
 ### BIOS
 
 The BIOS settings can be managed through the CPU UART console by enabling