[PATCH 2/2] imx8mn/8mp: Select ENV_IS_NOWHERE

[Fabio Estevam <festevam@gmail.com>]

From: Fabio Estevam <festevam@denx.de>

Currently, on i.MX8MN/i.MX8MP (Bootrom version 2) it is not possible to
load U-Boot via serial download mode, unless CONFIG_ENV_IS_NOWHERE is
selected.

This was noticed before by Adam Ford and fixed on the imx8mn beacon
board in commit 2c7ebf7778cf ("imx: imx8mn_beacon: Fix USB booting").

Such commit log states:

"The i.MX8M Nano can boot over USB using the boot ROM instead of
adding extra code to SPL to support USB drivers, etc.  However,
when booting from USB, the environment doesnt' know where to load
and causes a hang.  Fix this hang by supporting CONFIG_ENV_IS_NOWHERE=y.
It only falls back to this condition when booting from USB, so it
does not impact MMC booting."

Select ENV_IS_NOWHERE globally when i.MX8MN or i.MX8MP are used,
so that serial download mode can be used by default on these SoCs.

Signed-off-by: Fabio Estevam <festevam@denx.de>
---
 arch/arm/mach-imx/imx8m/Kconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/mach-imx/imx8m/Kconfig b/arch/arm/mach-imx/imx8m/Kconfig
index 55db25062a9b..ba7328aec8a1 100644
--- a/arch/arm/mach-imx/imx8m/Kconfig
+++ b/arch/arm/mach-imx/imx8m/Kconfig
@@ -16,10 +16,12 @@ config IMX8MM
 config IMX8MN
 	bool
 	select IMX8M
+	select ENV_IS_NOWHERE
 
 config IMX8MP
 	bool
 	select IMX8M
+	select ENV_IS_NOWHERE
 
 config SYS_SOC
 	default "imx8m"
-- 
2.25.1