/*
* arch/s390/kernel/relocate_kernel.S
*
* (C) Copyright IBM Corp. 2005
*
* Author(s): Rolf Adelsberger <adelsberger@de.ibm.com>
*
*/
/*
* moves the new kernel to its destination...
* %r2 = pointer to first kimage_entry_t
* %r3 = start address - where to jump to after the job is done...
*
* %r5 will be used as temp. storage
* %r6 holds the destination address
* %r7 = PAGE_SIZE
* %r8 holds the source address
* %r9 = PAGE_SIZE
* %r10 is a page mask
*/
.text
.globl relocate_kernel
relocate_kernel:
basr %r13,0 #base address
.base:
spx zero64-.base(%r13) #absolute addressing mode
stnsm sys_msk-.base(%r13),0xf8 #disable DAT and IRQ (external)
lhi %r10,-1 #preparing the mask
sll %r10,12 #shift it such that it becomes 0xf000
.top:
lhi %r7,4096 #load PAGE_SIZE in r7
lhi %r9,4096 #load PAGE_SIZE in r9
l %r5,0(%r2) #read another word for indirection page
ahi %r2,4 #increment pointer
tml %r5,0x1 #is it a destination page?
je .indir_check #NO, goto "indir_check"
lr %r6,%r5 #r6 = r5
nr %r6,%r10 #mask it out and...
j .top #...next iteration
.indir_check:
tml %r5,0x2 #is it a indirection page?
je .done_test #NO, goto "done_test"
nr %r5,%r10 #YES, mask out,
lr %r2,%r5 #move it into the right register,
j .top #and read next...
.done_test:
tml %r5,0x4 #is it the done indicator?
je .source_test #NO! Well, then it should be the source indicator...
j .done #ok, lets finish it here...
.source_test:
tml %r5,0x8 #it should be a source indicator...
je .top #NO, ignore it...
lr %r8,%r5 #r8 = r5
nr %r8,%r10 #masking
0: mvcle %r6,%r8,0x0 #copy PAGE_SIZE bytes from r8 to r6 - pad with 0
jo 0b
j .top
.done:
sr %r0,%r0 #clear register r0
la %r4,load_psw-.base(%r13) #load psw-address into the register
o %r3,4(%r4) #or load address into psw
st %r3,4(%r4)
mvc 0(8,%r0),0(%r4) #copy psw to absolute address 0
sr %r1,%r1 #clear %r1
sr %r2,%r2 #clear %r2
sigp %r1,%r2,0x12 #set cpuid to zero
lpsw 0 #hopefully start new kernel...
.align 8
zero64:
.quad 0
load_psw:
.long 0x00080000,0x80000000
sys_msk:
.quad 0
relocate_kernel_end:
.globl relocate_kernel_len
relocate_kernel_len:
.quad relocate_kernel_end - relocate_kernel
