1/*
  2 * S390 kdump lowlevel functions (new kernel)
  3 *
  4 * Copyright IBM Corp. 2011
  5 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
  6 */
  7
  8#define DATAMOVER_ADDR	0x4000
  9#define COPY_PAGE_ADDR	0x6000
 10
 11#ifdef CONFIG_CRASH_DUMP
 12
 13#
 14# kdump entry (new kernel - not yet relocated)
 15#
 16# Note: This code has to be position independent
 17#
 18
 19.align 2
 20.Lep_startup_kdump:
 21	lhi	%r1,2				# mode 2 = esame (dump)
 22	sigp	%r1,%r0,0x12			# Switch to esame mode
 23	sam64					# Switch to 64 bit addressing
 24	basr	%r13,0
 25.Lbase:
 26	larl	%r2,.Lbase_addr			# Check, if we have been
 27	lg	%r2,0(%r2)			# already relocated:
 28	clgr	%r2,%r13			#
 29	jne	.Lrelocate			# No : Start data mover
 30	lghi	%r2,0				# Yes: Start kdump kernel
 31	brasl	%r14,startup_kdump_relocated
 32
 33.Lrelocate:
 34	larl	%r4,startup
 35	lg	%r2,0x418(%r4)			# Get kdump base
 36	lg	%r3,0x420(%r4)			# Get kdump size
 37
 38	larl	%r10,.Lcopy_start		# Source of data mover
 39	lghi	%r8,DATAMOVER_ADDR		# Target of data mover
 40	mvc	0(256,%r8),0(%r10)		# Copy data mover code
 41
 42	agr	%r8,%r2				# Copy data mover to
 43	mvc	0(256,%r8),0(%r10)		# reserved mem
 44
 45	lghi	%r14,DATAMOVER_ADDR		# Jump to copied data mover
 46	basr	%r14,%r14
 47.Lbase_addr:
 48	.quad	.Lbase
 49
 50#
 51# kdump data mover code (runs at address DATAMOVER_ADDR)
 52#
 53# r2: kdump base address
 54# r3: kdump size
 55#
 56.Lcopy_start:
 57	basr	%r13,0				# Base
 580:
 59	lgr	%r11,%r2			# Save kdump base address
 60	lgr	%r12,%r2
 61	agr	%r12,%r3			# Compute kdump end address
 62
 63	lghi	%r5,0
 64	lghi	%r10,COPY_PAGE_ADDR		# Load copy page address
 651:
 66	mvc	0(256,%r10),0(%r5)		# Copy old kernel to tmp
 67	mvc	0(256,%r5),0(%r11)		# Copy new kernel to old
 68	mvc	0(256,%r11),0(%r10)		# Copy tmp to new
 69	aghi	%r11,256
 70	aghi	%r5,256
 71	clgr	%r11,%r12
 72	jl	1b
 73
 74	lg	%r14,.Lstartup_kdump-0b(%r13)
 75	basr	%r14,%r14			# Start relocated kernel
 76.Lstartup_kdump:
 77	.long	0x00000000,0x00000000 + startup_kdump_relocated
 78.Lcopy_end:
 79
 80#
 81# Startup of kdump (relocated new kernel)
 82#
 83.align 2
 84startup_kdump_relocated:
 85	basr	%r13,0
 860:
 87	mvc	0(8,%r0),.Lrestart_psw-0b(%r13)	# Setup restart PSW
 88	sam31					# Switch to 31 bit addr mode
 89	sr	%r1,%r1				# Erase register r1
 90	sr	%r2,%r2				# Erase register r2
 91	sigp	%r1,%r2,0x12			# Switch to 31 bit arch mode
 92	lpsw	0				# Start new kernel...
 93.align	8
 94.Lrestart_psw:
 95	.long	0x00080000,0x80000000 + startup
 96#else
 97.align 2
 98.Lep_startup_kdump:
 99#ifdef CONFIG_64BIT
100	larl	%r13,startup_kdump_crash
101	lpswe	0(%r13)
102.align 8
103startup_kdump_crash:
104	.quad	0x0002000080000000,0x0000000000000000 + startup_kdump_crash
105#else
106	basr	%r13,0
1070:	lpsw	startup_kdump_crash-0b(%r13)
108.align 8
109startup_kdump_crash:
110	.long	0x000a0000,0x00000000 + startup_kdump_crash
111#endif /* CONFIG_64BIT */
112#endif /* CONFIG_CRASH_DUMP */