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microwindows移植到S3C44B0的源码

	clc   0(3,%r2),.L_hdr		       # skip HDRx and EOFx 
	bz    .Lagain2
	clc   0(3,%r2),.L_eof
	bz    .Lagain2

#ifdef CONFIG_IPL_VM
#
# reset files in VM reader
#
        stidp __LC_CPUID                       # store cpuid
	tm    __LC_CPUID,0xff                  # running VM ?
	bno   .Lnoreset
        la    %r2,.Lreset              
        lhi   %r3,26
        .long 0x83230008
.Lnoreset:
#endif
	
#
# everything loaded, go for it
#
.Lnoload:
        l     %r1,.Lstartup
        br    %r1

.Lparm:	.long  PARMAREA
.Lstartup: .long startup
.Lcvtab:.long  _ebcasc                         # ebcdic to ascii table
.Lreset:.byte  0xc3,0xc8,0xc1,0xd5,0xc7,0xc5,0x40,0xd9,0xc4,0xd9,0x40
        .byte  0xc1,0xd3,0xd3,0x40,0xd2,0xc5,0xc5,0xd7,0x40,0xd5,0xd6
        .byte  0xc8,0xd6,0xd3,0xc4             # "change rdr all keep nohold"
.L_eof: .long  0xc5d6c600       /* C'EOF' */
.L_hdr: .long  0xc8c4d900       /* C'HDR' */

#endif  /* CONFIG_IPL */

#
# SALIPL loader support. Based on a patch by Rob van der Heij.
# This entry point is called directly from the SALIPL loader and
# doesn't need a builtin ipl record.
#
        .org  0x800
	.globl start
start:
	stm   %r0,%r15,0x07b0		# store registers
	basr  %r12,%r0
.base:
	l     %r11,.parm
	l     %r8,.cmd			# pointer to command buffer

	ltr   %r9,%r9			# do we have SALIPL parameters?
	bp    .sk8x8

	mvc   0(64,%r8),0x00b0		# copy saved registers
	xc    64(240-64,%r8),0(%r8)	# remainder of buffer
	tr    0(64,%r8),.lowcase	
	b     .gotr
.sk8x8:
	mvc   0(240,%r8),0(%r9)		# copy iplparms into buffer
.gotr:
	l     %r10,.tbl			# EBCDIC to ASCII table
	tr    0(240,%r8),0(%r10)
	stidp __LC_CPUID		# Are we running on VM maybe
	cli   __LC_CPUID,0xff
	bnz   .test
	.long 0x83300060		# diag 3,0,x'0060' - storage size
	b     .done
.test:
	mvc   0x68(8),.pgmnw		# set up pgm check handler
	l     %r2,.fourmeg
	lr    %r3,%r2
	bctr  %r3,%r0			# 4M-1
.loop:  iske  %r0,%r3
	ar    %r3,%r2
.pgmx:
	sr    %r3,%r2
	la    %r3,1(%r3)
.done:
        l     %r1,.memsize
	st    %r3,0(%r1)
	slr   %r0,%r0
	st    %r0,INITRD_SIZE-PARMAREA(%r11)
	st    %r0,INITRD_START-PARMAREA(%r11)
	j     startup                   # continue with startup
.tbl:	.long _ebcasc			# translate table
.cmd:	.long COMMAND_LINE		# address of command line buffer
.parm:	.long PARMAREA
.memsize: .long memory_size
.fourmeg: .long 0x00400000      	# 4M
.pgmnw:	.long 0x00080000,.pgmx
.lowcase:
	.byte 0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07 
	.byte 0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f
	.byte 0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17 
	.byte 0x18,0x19,0x1a,0x1b,0x1c,0x1d,0x1e,0x1f
	.byte 0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27 
	.byte 0x28,0x29,0x2a,0x2b,0x2c,0x2d,0x2e,0x2f
	.byte 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37 
	.byte 0x38,0x39,0x3a,0x3b,0x3c,0x3d,0x3e,0x3f
	.byte 0x40,0x41,0x42,0x43,0x44,0x45,0x46,0x47 
	.byte 0x48,0x49,0x4a,0x4b,0x4c,0x4d,0x4e,0x4f
	.byte 0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57 
	.byte 0x58,0x59,0x5a,0x5b,0x5c,0x5d,0x5e,0x5f
	.byte 0x60,0x61,0x62,0x63,0x64,0x65,0x66,0x67 
	.byte 0x68,0x69,0x6a,0x6b,0x6c,0x6d,0x6e,0x6f
	.byte 0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77 
	.byte 0x78,0x79,0x7a,0x7b,0x7c,0x7d,0x7e,0x7f

	.byte 0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87 
	.byte 0x88,0x89,0x8a,0x8b,0x8c,0x8d,0x8e,0x8f
	.byte 0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97 
	.byte 0x98,0x99,0x9a,0x9b,0x9c,0x9d,0x9e,0x9f
	.byte 0xa0,0xa1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7 
	.byte 0xa8,0xa9,0xaa,0xab,0xac,0xad,0xae,0xaf
	.byte 0xb0,0xb1,0xb2,0xb3,0xb4,0xb5,0xb6,0xb7 
	.byte 0xb8,0xb9,0xba,0xbb,0xbc,0xbd,0xbe,0xbf
	.byte 0xc0,0x81,0x82,0x83,0x84,0x85,0x86,0x87	# .abcdefg 
	.byte 0x88,0x89,0xca,0xcb,0xcc,0xcd,0xce,0xcf	# hi
	.byte 0xd0,0x91,0x92,0x93,0x94,0x95,0x96,0x97 	# .jklmnop
	.byte 0x98,0x99,0xda,0xdb,0xdc,0xdd,0xde,0xdf	# qr
	.byte 0xe0,0xe1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7	# ..stuvwx
	.byte 0xa8,0xa9,0xea,0xeb,0xec,0xed,0xee,0xef	# yz
	.byte 0xf0,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7 
	.byte 0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfe,0xff

#
# startup-code at 0x10000, running in real mode
# this is called either by the ipl loader or directly by PSW restart
# or linload or SALIPL
#
        .org  0x10000
startup:basr  %r13,0                     # get base
.LPG1:  lctl  %c0,%c15,.Lctl-.LPG1(%r13) # load control registers
	la    %r12,_pstart-.LPG1(%r13)   # pointer to parameter area
					 # move IPL device to lowcore
        mvc   __LC_IPLDEV(4),IPL_DEVICE-PARMAREA(%r12)
	
#
# find memory chunks.
#
	mvc   __LC_PGM_NEW_PSW(8),.Lpcmem-.LPG1(%r13)
	la    %r1,1                      # test in increments of 128KB
	sll   %r1,17
	l     %r3,.Lmchunk-.LPG1(%r13)   # get pointer to memory_chunk array
	slr   %r4,%r4                    # set start of chunk to zero
	slr   %r5,%r5                    # set end of chunk to zero
	slr   %r6,%r6			 # set access code to zero
.Lloop:
	tprot 0(%r5),0			 # test protection of first byte
	ipm   %r7
	srl   %r7,28
	clr   %r6,%r7			 # compare cc with last access code
	be    .Lsame-.LPG1(%r13)
	clr   %r4,%r5			 # chunk size > 0?
	be    .Lsize0-.LPG1(%r13)
	st    %r4,0(%r3)		 # store start address of chunk
	lr    %r0,%r5
	slr   %r0,%r4
	st    %r0,4(%r3)		 # store size of chunk
	st    %r6,8(%r3)		 # store type of chunk
	la    %r3,12(%r3)
	lr    %r4,%r5			 # set start to end
.Lsize0:
	lr    %r6,%r7			 # set access code to last cc
.Lsame:
	ar    %r5,%r1			 # add 128KB to end of chunk
	bno   .Lloop-.LPG1(%r13)	 # r1 < 0x80000000 -> loop
.Lchkmem:				 # > 2GB or tprot got a program check
	clr   %r4,%r5			 # chunk size > 0?
	be    .Ldonemem-.LPG1(%r13)
	st    %r4,0(%r3)		 # store start address of chunk
	lr    %r0,%r5
	slr   %r0,%r4
	st    %r0,4(%r3)		 # store size of chunk
	st    %r6,8(%r3)		 # store type of chunk
.Ldonemem:		
        l     %r1,.Lmemsize-.LPG1(%r13)  # address of variable memory_size
	st    %r5,0(%r1)                 # store last end to memory size
	
        l      %r12,.Lmflags-.LPG1(%r13) # get address of machine_flags
#
# find out if we are running under VM
#
        stidp  __LC_CPUID               # store cpuid
	tm     __LC_CPUID,0xff          # running under VM ?
	bno    .Lnovm-.LPG1(%r13)
        oi     3(%r12),1                # set VM flag
.Lnovm:
        lh     %r0,__LC_CPUID+4         # get cpu version
        chi    %r0,0x7490               # running on a P/390 ?
        bne    .Lnop390-.LPG1(%r13)
        oi     3(%r12),4                # set P/390 flag
.Lnop390:

#
# find out if we have an IEEE fpu
#
        mvc    __LC_PGM_NEW_PSW(8),.Lpcfpu-.LPG1(%r13)
	efpc   %r0,0                    # test IEEE extract fpc instruction
        oi     3(%r12),2                # set IEEE fpu flag
.Lchkfpu:

#
# find out if we have the CSP instruction
#
       mvc    __LC_PGM_NEW_PSW(8),.Lpccsp-.LPG1(%r13)
       la     %r0,0
       lr     %r1,%r0
       la     %r2,4
       csp    %r0,%r2                   # Test CSP instruction
       oi     3(%r12),8                 # set CSP flag
.Lchkcsp:

#
# find out if we have the MVPG instruction
#
       mvc    __LC_PGM_NEW_PSW(8),.Lpcmvpg-.LPG1(%r13)
       sr     %r0,%r0
       la     %r1,0
       la     %r2,0
       mvpg   %r1,%r2                   # Test CSP instruction
       oi     3(%r12),16                # set MVPG flag
.Lchkmvpg:

        lpsw  .Lentry-.LPG1(13)         # jump to _stext in primary-space,
                                        # virtual and never return ...
        .align 8
.Lentry:.long  0x00080000,0x80000000 + _stext
.Lctl:  .long  0x04b50002               # cr0: various things
        .long  0                        # cr1: primary space segment table
        .long  .Lduct                   # cr2: dispatchable unit control table
        .long  0                        # cr3: instruction authorization
        .long  0                        # cr4: instruction authorization
        .long  0                        # cr5:  various things
        .long  0                        # cr6:  I/O interrupts
        .long  0                        # cr7:  secondary space segment table
        .long  0                        # cr8:  access registers translation
        .long  0                        # cr9:  tracing off
        .long  0                        # cr10: tracing off
        .long  0                        # cr11: tracing off
        .long  0                        # cr12: tracing off
        .long  0                        # cr13: home space segment table
        .long  0xc0000000               # cr14: machine check handling off
        .long  0                        # cr15: linkage stack operations
.Lpcmem:.long  0x00080000,0x80000000 + .Lchkmem
.Lpcfpu:.long  0x00080000,0x80000000 + .Lchkfpu
.Lpccsp:.long  0x00080000,0x80000000 + .Lchkcsp
.Lpcmvpg:.long 0x00080000,0x80000000 + .Lchkmvpg
.Lmemsize:.long memory_size
.Lmchunk:.long memory_chunk
.Lmflags:.long machine_flags

	.org PARMAREA-64
.Lduct:	.long 0,0,0,0,0,0,0,0
	.long 0,0,0,0,0,0,0,0

#
# params at 10400 (setup.h)
#
	.org   PARMAREA
	.global _pstart
_pstart:	
        .long  0,0                      # IPL_DEVICE
        .long  0,RAMDISK_ORIGIN         # INITRD_START
        .long  0,RAMDISK_SIZE           # INITRD_SIZE

        .org   COMMAND_LINE
    	.byte  "root=/dev/ram0 ro"
        .byte  0
	.org   0x11000
	.global _pend
_pend:	

#ifdef CONFIG_SHARED_KERNEL
	.org   0x100000
#endif

#
# startup-code, running in virtual mode
#
        .globl _stext
_stext:	basr  %r13,0                    # get base
.LPG2:
#
# Setup stack
#
        l     %r15,.Linittu-.LPG2(%r13)
        ahi   %r15,8192                 # init_task_union + 8192
        st    %r15,__LC_KERNEL_STACK    # set end of kernel stack
        ahi   %r15,-96
        xc    0(4,%r15),0(%r15)         # set backchain to zero

#
# clear bss memory
#
        l     %r2,.Lbss_bgn-.LPG2(%r13) # start of bss
        l     %r3,.Lbss_end-.LPG2(%r13) # end of bss
        sr    %r3,%r2                   # length of bss
        sr    %r4,%r4                   #
        sr    %r5,%r5                   # set src,length and pad to zero
        sr    %r0,%r0                   #
        mvcle %r2,%r4,0                 # clear mem
        jo    .-4                       # branch back, if not finish
# check control registers
        stctl  %c0,%c15,0(%r15)
	oi     2(%r15),0x20             # enable sigp external interrupts
	oi     0(%r15),0x10             # switch on low address protection
        lctl   %c0,%c15,0(%r15)

#
        lam    0,15,.Laregs-.LPG2(%r13) # load access regs needed by uaccess
        l      %r14,.Lstart-.LPG2(%r13)
        basr   %r14,%r14                # call start_kernel
#
# We returned from start_kernel ?!? PANIK
#
        basr  %r13,0
	lpsw  .Ldw-.(%r13)           # load disabled wait psw
#
            .align 8
.Ldw:	    .long  0x000a0000,0x00000000
.Linittu:   .long  init_task_union
.Lstart:    .long  start_kernel
.Lbss_bgn:  .long  __bss_start
.Lbss_end:  .long  _end
.Laregs:    .long  0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0