doc: qemu-riscv: describe CONFIG_DEBUG_SBI_CONSOLE
In main U-Boot the SBI DBCN extension can be used to supply a debug
console.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/doc/board/emulation/qemu-riscv.rst b/doc/board/emulation/qemu-riscv.rst
index 8a5eb1e..8388e13 100644
--- a/doc/board/emulation/qemu-riscv.rst
+++ b/doc/board/emulation/qemu-riscv.rst
@@ -171,3 +171,8 @@
CONFIG_DEBUG_UART_NS16550=y
CONFIG_DEBUG_UART_BASE=0x10000000
CONFIG_DEBUG_UART_CLOCK=3686400
+
+To provide a debug UART in main U-Boot the SBI DBCN extension can be used
+instead::
+
+ CONFIG_DEBUG_SBI_CONSOLE=y