1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * S390 kdump lowlevel functions (new kernel)
  4 *
  5 * Copyright IBM Corp. 2011
  6 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
  7 */
  8
  9#include <asm/sigp.h>
 10
 11#define DATAMOVER_ADDR	0x4000
 12#define COPY_PAGE_ADDR	0x6000
 13
 14#ifdef CONFIG_CRASH_DUMP
 15
 16#
 17# kdump entry (new kernel - not yet relocated)
 18#
 19# Note: This code has to be position independent
 20#
 21
 22.align 2
 23.Lep_startup_kdump:
 24	lhi	%r1,2				# mode 2 = esame (dump)
 25	sigp	%r1,%r0,SIGP_SET_ARCHITECTURE	# Switch to esame mode
 26	sam64					# Switch to 64 bit addressing
 27	basr	%r13,0
 28.Lbase:
 29	larl	%r2,.Lbase_addr			# Check, if we have been
 30	lg	%r2,0(%r2)			# already relocated:
 31	clgr	%r2,%r13			#
 32	jne	.Lrelocate			# No : Start data mover
 33	lghi	%r2,0				# Yes: Start kdump kernel
 34	brasl	%r14,startup_kdump_relocated
 35
 36.Lrelocate:
 37	larl	%r4,startup
 38	lg	%r2,0x418(%r4)			# Get kdump base
 39	lg	%r3,0x420(%r4)			# Get kdump size
 40
 41	larl	%r10,.Lcopy_start		# Source of data mover
 42	lghi	%r8,DATAMOVER_ADDR		# Target of data mover
 43	mvc	0(256,%r8),0(%r10)		# Copy data mover code
 44
 45	agr	%r8,%r2				# Copy data mover to
 46	mvc	0(256,%r8),0(%r10)		# reserved mem
 47
 48	lghi	%r14,DATAMOVER_ADDR		# Jump to copied data mover
 49	basr	%r14,%r14
 50.Lbase_addr:
 51	.quad	.Lbase
 52
 53#
 54# kdump data mover code (runs at address DATAMOVER_ADDR)
 55#
 56# r2: kdump base address
 57# r3: kdump size
 58#
 59.Lcopy_start:
 60	basr	%r13,0				# Base
 610:
 62	lgr	%r11,%r2			# Save kdump base address
 63	lgr	%r12,%r2
 64	agr	%r12,%r3			# Compute kdump end address
 65
 66	lghi	%r5,0
 67	lghi	%r10,COPY_PAGE_ADDR		# Load copy page address
 681:
 69	mvc	0(256,%r10),0(%r5)		# Copy old kernel to tmp
 70	mvc	0(256,%r5),0(%r11)		# Copy new kernel to old
 71	mvc	0(256,%r11),0(%r10)		# Copy tmp to new
 72	aghi	%r11,256
 73	aghi	%r5,256
 74	clgr	%r11,%r12
 75	jl	1b
 76
 77	lg	%r14,.Lstartup_kdump-0b(%r13)
 78	basr	%r14,%r14			# Start relocated kernel
 79.Lstartup_kdump:
 80	.long	0x00000000,0x00000000 + startup_kdump_relocated
 81.Lcopy_end:
 82
 83#
 84# Startup of kdump (relocated new kernel)
 85#
 86.align 2
 87startup_kdump_relocated:
 88	basr	%r13,0
 890:	lpswe	.Lrestart_psw-0b(%r13)		# Start new kernel...
 90.align	8
 91.Lrestart_psw:
 92	.quad	0x0000000080000000,0x0000000000000000 + startup
 93#else
 94.align 2
 95.Lep_startup_kdump:
 96	larl	%r13,startup_kdump_crash
 97	lpswe	0(%r13)
 98.align 8
 99startup_kdump_crash:
100	.quad	0x0002000080000000,0x0000000000000000 + startup_kdump_crash
101#endif /* CONFIG_CRASH_DUMP */