[PATCH] kexec: s390 support
Add kexec support for s390 architecture.
From: Milton Miller <miltonm@bga.com>
- Fix passing of first argument to relocate_kernel assembly.
- Fix Kconfig description.
- Remove wrong comment and comments that describe obvious things.
- Allow only KEXEC_TYPE_DEFAULT as image type -> dump not supported.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/s390/kernel/relocate_kernel.S b/arch/s390/kernel/relocate_kernel.S
new file mode 100644
index 0000000..d5e4a62
--- /dev/null
+++ b/arch/s390/kernel/relocate_kernel.S
@@ -0,0 +1,81 @@
+/*
+ * 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