• David S. Miller's avatar
    [SPARC64]: Rewrite bootup sequence. · bff06d55
    David S. Miller authored
    Instead of all of this cpu-specific code to remap the kernel
    to the correct location, use portable firmware calls to do
    this instead.
    
    What we do now is the following in position independant
    assembler:
    
    	chosen_node = prom_finddevice("/chosen");
    	prom_mmu_ihandle_cache = prom_getint(chosen_node, "mmu");
    	vaddr = 4MB_ALIGN(current_text_addr());
    	prom_translate(vaddr, &paddr_high, &paddr_low, &mode);
    	prom_boot_mapping_mode = mode;
    	prom_boot_mapping_phys_high = paddr_high;
    	prom_boot_mapping_phys_low = paddr_low;
    	prom_map(-1, 8 * 1024 * 1024, KERNBASE, paddr_low);
    
    and that replaces the massive amount of by-hand TLB probing and
    programming we used to do here.
    
    The new code should also handle properly the case where the kernel
    is mapped at the correct address already (think: future kexec
    support).
    
    Consequently, the bulk of remap_kernel() dies as does the entirety
    of arch/sparc64/prom/map.S
    
    We try to share some strings in the PROM library with the ones used
    at bootup, and while we're here mark input strings to oplib.h routines
    with "const" when appropriate.
    
    There are many more simplifications now possible.  For one thing, we
    can consolidate the two copies we now have of a lot of cpu setup code
    sitting in head.S and trampoline.S.
    
    This is a significant step towards CONFIG_DEBUG_PAGEALLOC support.
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    bff06d55
head.S 13.3 KB