Device tree memory regions may have sizes larger than 4GB. Instead of silently truncating a 64 bit size when we pass it to arm_add_memory(), split large regions into 2GB chunks.
Signed-off-by: Peter Maydell peter.maydell@linaro.org --- With this patch, I can take a device tree which has been tweaked so its #address-cells and #size-cells are both 2, and boot it on a QEMU vexpress-a15 model with >4GB of RAM, and have the kernel actually detect the right amount of RAM. [the qemu bit needs some patches I haven't posted yet.]
Since I'm not really a kernel dev I thought I'd post this to linaro-dev first in the hope of a bit of friendly local review before venturing onto lkml :-) (Apologies to those on cc who got this twice because I mistyped the linaro-dev email address.)
arch/arm/kernel/devtree.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c index bee7f9d..79a6e66 100644 --- a/arch/arm/kernel/devtree.c +++ b/arch/arm/kernel/devtree.c @@ -26,6 +26,11 @@
void __init early_init_dt_add_memory_arch(u64 base, u64 size) { + while (size > 0x80000000) { + arm_add_memory(base, 0x80000000); + base += 0x80000000; + size -= 0x80000000; + } arm_add_memory(base, size); }