The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of pages. This option selects the largest power of two that the kernel keeps in the memory allocator. If you need to allocate very large blocks of physically contiguous memory, then you may need to increase this value. This config option is actually maximum order plus one. For example, a value of 11 means that the largest free memory block is 2^10 pages.
Nios II CPUs cannot fetch/store data which is not bus aligned, i.e., a 2 or 4 byte fetch must start at an address divisible by 2 or 4. Any non-aligned load/store instructions will be trapped and emulated in software if you say Y here, which has a performance impact.
On some platforms, there is currently no way for the boot loader to pass arguments to the kernel. For these platforms, you can supply some command-line options at build time by entering them here. In other cases you can specify kernel args so that you don't have to set them up in board prom initialization routines.
Set this to have arguments from the default kernel command string override those passed by the boot loader.
Set this to ignore the bootargs property from the devicetree's chosen node and fall back to CMDLINE if nothing is passed.
Use bootargs env variable from u-boot for kernel command line. will override "Default kernel command string". Say N if you are unsure.
This option allows you to set the link address offset of the zImage. This can be useful if you are on a board which has a small amount of memory.
This option allows you to set the virtual address of the kernel MMU region. Say N here unless you know what you are doing.
This option allows you to set the virtual base address of the kernel MMU region.
This option allows you to set the virtual address of the kernel region. Say N here unless you know what you are doing.
This option allows you to set the virtual address of the I/O region. Say N here unless you know what you are doing.