[U-Boot] [PATCH v2 5/6] sunxi: add Kconfig option for the maximum accessible DRAM

[Icenowy Zheng]

Allwinner 64-bit SoCs can use 4GiB DRAM chip, however their memory map
has only allocated 3GiB for DRAM, so only 3GiB of the DRAM is
accessible.

Add a Kconfig option for the maximum accessible DRAM.

For A80 it should be a much higher value (8GiB), but as I have no A80
device to test and originally U-Boot only supports 2GiB DRAM on A80, it
currently still falls under the 2GiB situation.

Signed-off-by: Icenowy Zheng <icenowy at aosc.io>
---
This used to be in another patchset targeting 3GiB support.

Changes in v2:
- Add H6 to SoCs that support 3GiB DRAM.

 arch/arm/mach-sunxi/Kconfig | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/mach-sunxi/Kconfig b/arch/arm/mach-sunxi/Kconfig
index 764337c643..e9e1b4bc0e 100644
--- a/arch/arm/mach-sunxi/Kconfig
+++ b/arch/arm/mach-sunxi/Kconfig
@@ -140,6 +140,14 @@ config MACH_SUNXI_H3_H5
 	select SUNXI_GEN_SUN6I
 	select SUPPORT_SPL
 
+# TODO: try out A80's 8GiB DRAM space
+config SUNXI_DRAM_MAX_SIZE
+	hex
+	default 0xC0000000 if MACH_SUN50I
+	default 0xC0000000 if MACH_SUN50I_H5
+	default 0xC0000000 if MACH_SUN50I_H6
+	default 0x80000000
+
 choice
 	prompt "Sunxi SoC Variant"
 	optional
-- 
2.18.1