android_kernel_xiaomi_sm8350/arch/s390/kernel/relocate_kernel.S
Heiko Carstens 15e9b586e0 [S390] Reset infrastructure for re-IPL.
In case of re-IPL and diag308 doesn't work we have to reset all devices
manually and wait synchronously that each reset finished.
This patch adds the necessary infrastucture and the first exploiter of it.

Subsystems that need to add a function that needs to be called at re-IPL
may register/unregister this function via

struct reset_call {
	struct reset_call *next;
	void (*fn)(void);
};

void register_reset_call(struct reset_call *reset);
void unregister_reset_call(struct reset_call *reset);

When the registered function get called the context is:

- all cpus beside the current one are stopped
- all machine checks and interrupts are disabled
- prefixing is disabled
- a default machine check handler is available for use

The registered functions may not take any locks are sleep.

For the common I/O layer part of this patch:

Introduce a reset_call css_reset that does the following:
- clear all subchannels
- perform a rchp on all channel paths and wait for the resulting
  machine checks
This replaces the calls to clear_all_subchannels() and
cio_reset_channel_paths() for kexec and ccw reipl. reipl_ccw_dev() now
uses reipl_find_schid() to determine the subchannel id for a given
device id.
Also remove cio_reset_channel_paths() and friends since they are not
needed anymore.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04 15:40:26 +01:00

118 lines
2.9 KiB
ArmAsm

/*
* arch/s390/kernel/relocate_kernel.S
*
* (C) Copyright IBM Corp. 2005
*
* Author(s): Rolf Adelsberger,
* Heiko Carstens <heiko.carstens@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:
stnsm sys_msk-.base(%r13),0xfb # disable DAT
stctl %c0,%c15,ctlregs-.base(%r13)
stm %r0,%r15,gprregs-.base(%r13)
la %r1,load_psw-.base(%r13)
mvc 0(8,%r0),0(%r1)
la %r0,.back-.base(%r13)
st %r0,4(%r0)
oi 4(%r0),0x80
mvc 0x68(8,%r0),0(%r1)
la %r0,.back_pgm-.base(%r13)
st %r0,0x6c(%r0)
oi 0x6c(%r0),0x80
lhi %r0,0
diag %r0,%r0,0x308
.back:
basr %r13,0
.back_base:
oi have_diag308-.back_base(%r13),0x01
lctl %c0,%c15,ctlregs-.back_base(%r13)
lm %r0,%r15,gprregs-.back_base(%r13)
j .start_reloc
.back_pgm:
lm %r0,%r15,gprregs-.base(%r13)
.start_reloc:
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
tm have_diag308-.base(%r13),0x01
jno .no_diag308
diag %r0,%r0,0x308
.no_diag308:
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
load_psw:
.long 0x00080000,0x80000000
sys_msk:
.quad 0
ctlregs:
.rept 16
.long 0
.endr
gprregs:
.rept 16
.long 0
.endr
have_diag308:
.byte 0
.align 8
relocate_kernel_end:
.globl relocate_kernel_len
relocate_kernel_len:
.quad relocate_kernel_end - relocate_kernel