x86: Enable debug UART for Minnowmax

[karo-tx-uboot.git] / arch / x86 / cpu / start.S

diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index e5c1733e594b0a4b2be7ae7f0f1849433382aedd..313fa3ff969f9c48c732c0e1fb2694e1bfc9de4f 100644 (file)
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -128,6 +128,15 @@ car_init_ret:
        andl    $0xfffffff0, %esp
        post_code(POST_START_STACK)
 
+       /*
+        * Debug UART is available here although it may not be plumbed out
+        * to pins depending on the board. To use it:
+        *
+        * call  debug_uart_init
+        * mov   $'a', %eax
+        * call  printch
+        */
+
        /* Zero the global data since it won't happen later */
        xorl    %eax, %eax
        movl    $GENERATED_GBL_DATA_SIZE, %ecx