[U-Boot] [PATCH v2 3/8] ARM: bcm283x: Define configs for RaspberryPi 4

[Andrei Gherzan]

Define two target configs for Raspberry Pi 4 (32 and 64bit) and the
corresponding BCM2838* configs.

Be aware of the current limitation in firmware which requires an
explicit configuration to force the arm in 64bit mode when the
respective target is used.

Signed-off-by: Andrei Gherzan <andrei at balena.io>
Signed-off-by: Matthias Brugger <mbrugger at suse.com>
---
 arch/arm/mach-bcm283x/Kconfig | 62 +++++++++++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)

diff --git a/arch/arm/mach-bcm283x/Kconfig b/arch/arm/mach-bcm283x/Kconfig
index 8e69914a83..09a5b42bbb 100644
--- a/arch/arm/mach-bcm283x/Kconfig
+++ b/arch/arm/mach-bcm283x/Kconfig
@@ -26,6 +26,23 @@ config BCM2837_64B
 	select BCM2837
 	select ARM64
 
+config BCM2838
+	bool "Broadcom BCM2838 SoC support"
+	depends on ARCH_BCM283X
+
+config BCM2838_32B
+	bool "Broadcom BCM2838 SoC 32-bit support"
+	depends on ARCH_BCM283X
+	select BCM2838
+	select ARMV7_LPAE
+	select CPU_V7A
+
+config BCM2838_64B
+	bool "Broadcom BCM2838 SoC 64-bit support"
+	depends on ARCH_BCM283X
+	select BCM2838
+	select ARM64
+
 menu "Broadcom BCM283X family"
 	depends on ARCH_BCM283X
 
@@ -127,6 +144,50 @@ config TARGET_RPI_3
 	  This option creates a build targeting the ARMv8/AArch64 ISA.
 	select BCM2837_64B
 
+config TARGET_RPI_4_32B
+	bool "Raspberry Pi 4 32-bit build"
+	help
+	  Support for all BCM2838-based Raspberry Pi variants, such as
+	  the RPi 4 model B, in AArch32 (32-bit) mode.
+
+	  This option assumes the VideoCore firmware is configured to use the
+	  mini UART (rather than PL011) for the serial console. This is the
+	  default on the RPi 4. To enable the UART console, the following non-
+	  default option must be present in config.txt: enable_uart=1. This is
+	  required for U-Boot to operate correctly, even if you only care
+	  about the HDMI/usbkbd console.
+
+	  Due to hardware incompatibilities, this can't be used with
+	  BCM283/5/6/7.
+
+	  This option creates a build targeting the ARMv7/AArch32 ISA.
+	select BCM2838_32B
+
+config TARGET_RPI_4
+	bool "Raspberry Pi 4 64-bit build"
+	help
+	  Support for all BCM2838-based Raspberry Pi variants, such as
+	  the RPi 4 model B, in AArch64 (64-bit) mode.
+
+	  This option assumes the VideoCore firmware is configured to use the
+	  mini UART (rather than PL011) for the serial console. This is the
+	  default on the RPi 4. To enable the UART console, the following non-
+	  default option must be present in config.txt: enable_uart=1. This is
+	  required for U-Boot to operate correctly, even if you only care
+	  about the HDMI/usbkbd console.
+
+	  Due to hardware incompatibilities, this can't be used with
+	  BCM283/5/6/7.
+
+	  Also, due to a bug in firmware, switching to 64bit mode doesn't
+	  happen automatically based on the kernel's image filename. See
+	  https://github.com/raspberrypi/firmware/issues/1193 for more details.
+	  Until that is resolved, the configuration (config.txt) needs to
+	  explicitly set: arm_64bit=1.
+
+	  This option creates a build targeting the ARMv8/AArch64 ISA.
+	select BCM2838_64B
+
 endchoice
 
 config SYS_BOARD
@@ -145,5 +206,6 @@ config BCM283x_BASE
 	hex
 	default "0x20000000" if BCM2835
 	default "0x3f000000" if BCM2836 || BCM2837
+	default "0xfe000000" if BCM2838
 
 endmenu
-- 
2.22.0