/*
* 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
/* status_t arch_start_kernel(struct kernel_args *kernelArgs,
addr_t kernelEntry, addr_t kernelStackTop)
r3 - kernelArgs
r4 - kernelEntry
r5 - kernelStackTop
*/
FUNCTION(arch_start_kernel):
// push a stack frame
stwu %r1, -32(%r1)
mflr %r0
stw %r0, 36(%r1)
// save the old stack pointer in r29
stw %r29, 20(%r1)
mr %r29, %r1
// set up the kernel stack
subi %r1, %r5, 16
// clear the pointer to the previous frame
li %r0, 0
stw %r0, 0(%r1)
// enter the kernel
mtlr %r4
li %r4, 0
blrl
/* Actually we should never get here, but at least for debugging purposes
it's quite nice to return in an orderly manner. */
// reset the boot loader stack
mr %r1, %r29
lwz %r29, 20(%r1)
// pop the stack frame
lwz %r0, 36(%r1)
mtlr %r0
addi %r1, %r1, 32
blr
