/*
 * Copyright 2005, Ingo Weinhold <bonefish@cs.tu-berlin.de>.
 * All rights reserved. Distributed under the terms of the MIT License.
 */

#define FUNCTION(x) .global x; .type x,@function; x

/*      status_t arch_start_kernel(struct kernel_args *kernelArgs,
                addr_t kernelEntry, addr_t kernelStackTop);

        o0      - kernelArgs
        o1      - kernelEntry
        o2      - kernelStackTop
*/
FUNCTION(arch_start_kernel):
        save  %sp, -176, %sp

        // Now we have
        // - Kernel args in i0
        // - Kernel entry in i1
        // - Kernel stack top in i2

        // Set the stack, adding the stack bias
        sub %i2, 2047, %sp // apply stack bias

        // We need to call the kernel with:
        // o0 = kernel args
        // o1 = current CPU
        mov %i0, %o0
        // Current CPU is always 0 on boot
        mov %g0, %o1

        // Jump into the kernel, store return address in o7
        jmpl %i1, %o7
        nop // branch delay slot...

        // We should never get here, but in case the kernel returns, attempt to
        // exit cleanly.

        // Forward the return code to the caller
        mov %o0, %i0

        // Since we saved our context at the start of this function,
        // a simple "return" should do the job and restore the previous register
        // window and put us back on the old stack
        return %i7 + 8
        nop // Branch delay slot...