x86: Allow use of serial soon after relocation
At present on x86 machines with use cache-as-RAM, the memory goes away just
before board_init_r() is called. This means that serial drivers are
no-longer unavailable, until initr_dm() it called, etc.
Any attempt to use printf() within this period will cause a hang.
To fix this, mark the serial devices as 'unavailable' when it is no-longer
available. Bring it back when serial_initialize() is called. This means that
the debug UART will be used instead for this period.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/common/board_f.c b/common/board_f.c
index 622093a..109025a 100644
--- a/common/board_f.c
+++ b/common/board_f.c
@@ -1096,6 +1096,13 @@
hang();
/*
+ * The pre-relocation drivers may be using memory that has now gone
+ * away. Mark serial as unavailable - this will fall back to the debug
+ * UART if available.
+ */
+ gd->flags &= ~GD_FLG_SERIAL_READY;
+
+ /*
* U-Boot has been copied into SDRAM, the BSS has been cleared etc.
* Transfer execution from Flash to RAM by calculating the address
* of the in-RAM copy of board_init_r() and calling it
diff --git a/drivers/serial/serial-uclass.c b/drivers/serial/serial-uclass.c
index f154eb1..0ce5c44 100644
--- a/drivers/serial/serial-uclass.c
+++ b/drivers/serial/serial-uclass.c
@@ -115,7 +115,7 @@
/* Called after relocation */
void serial_initialize(void)
{
- serial_find_console_or_panic();
+ serial_init();
}
static void _serial_putc(struct udevice *dev, char ch)