For the memory size ( > 512MB, < 1GB), the MSA setting is:
- SSEG0: PHY_START , PHY_START + 512MB
- SSEG1: PHY_START + 512MB, PHY_START + 1GB
But the real memory is no more than 1GB, there is a gap between the
end size of memory and border of 1GB. CPU could speculatively
execute to that gap and if the gap of the bus couldn't respond to
the CPU request, then the crash will happen.
Now make the setting with:
- SSEG0: PHY_START , PHY_START + 512MB (no change)
- SSEG1: Disabled (We use highmem to use the memory of 512MB~1GB)
We also deprecated zhole_szie[] settings, it's only used by arm
style CPUs. All memory gap should use Reserved setting of dts in
csky system.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Modify SETUP_MMU macro to fit on both MMU-on or MMU-off enviornment
and vmlinux could bootup from MMU off enviornment for some cases.
Unify the style of _start and _start_smp_secondary in head.S to make
head.S looks more concise and easy to understand.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
This patch add boot code. Thx boot params is all in dtb and it's
the only way to let kernel get bootloader param information.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>