• Magnus Damm's avatar
    sh: P4 ioremap pass-through · 716777db
    Magnus Damm authored
    This patch adds a pass-through case when ioremapping P4 addresses.
    
    Addresses passed to ioremap() should be physical addresses, so the
    best option is usually to convert the virtual address to a physical
    address before calling ioremap. This will give you a virtual address
    in P2 which matches the physical address and this works well for
    most internal hardware blocks on the SuperH architecture.
    
    However, some hardware blocks must be accessed through P4. Converting
    the P4 address to a physical and then back to a P2 does not work. One
    example of this is the sh7722 TMU block, it must be accessed through P4.
    
    Without this patch P4 addresses will be mapped using PTEs which
    requires the page allocator to be up and running.
    Signed-off-by: default avatarMagnus Damm <damm@igel.co.jp>
    Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
    716777db
addrspace.h 1.89 KB