ARM: tegra: query_sdram_size() cleanup
The return value of query_sdram_size() is assigned directly to gd->ram_size in dram_init(). Adjust the return type to match the field it's assigned to. This has the beneficial effect that on 64-bit systems, the return value can correctly represent large RAM sizes over 4GB. For similar reasons, change the type of variable size_bytes in the same way. query_sdram_size() would previously clip the detected RAM size to at most just under 4GB in all cases, since on 32-bit systems, larger values could not be represented. Disable this feature on 64-bit systems since the representation restriction does not exist. On 64-bit systems, never call get_ram_size() to validate the detected/ calculated RAM size. On any system with a secure OS/... carve-out, RAM may not have a single contiguous usable area, and this can confuse get_ram_size(). Ideally, we'd make this call conditional upon some other flag that indicates specifically that a carve-out is actually in use. At present, building for a 64-bit system is the best indication we have of this fact. In fact, the call to get_ram_size() is not useful by the time U-Boot runs on any system, since U-Boot (and potentially much other early boot software) always runs from RAM on Tegra, so any mistakes in memory controller register programming will already have manifested themselves and prevented U-Boot from running to this point. In the future, we may simply delete the call to get_ram_size() in all cases. Signed-off-by: NStephen Warren <swarren@nvidia.com> Signed-off-by: NTom Warren <twarren@nvidia.com>
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