crt.s revision 89495
189495Snyan# 289495Snyan# Copyright (c) 1999 Global Technology Associates, Inc. 389495Snyan# All rights reserved. 489495Snyan# 589495Snyan# Redistribution and use in source and binary forms, with or without 689495Snyan# modification, are permitted provided that the following conditions 789495Snyan# are met: 889495Snyan# 1. Redistributions of source code must retain the above copyright 989495Snyan# notice, this list of conditions and the following disclaimer. 1089495Snyan# 2. Redistributions in binary form must reproduce the above copyright 1189495Snyan# notice, this list of conditions and the following disclaimer in the 1289495Snyan# documentation and/or other materials provided with the distribution. 1389495Snyan# 1489495Snyan# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS``AS IS'' AND 1589495Snyan# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1689495Snyan# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 1789495Snyan# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 1889495Snyan# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 1989495Snyan# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 2089495Snyan# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 2189495Snyan# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 2289495Snyan# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 2389495Snyan# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 2489495Snyan# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 2589495Snyan# 2689495Snyan# From: btx.s 1.10 1999/02/25 16:27:41 rnordier 2789495Snyan# $FreeBSD: head/sys/boot/pc98/kgzldr/crt.s 89495 2002-01-18 09:00:38Z nyan $ 2889495Snyan# 2989495Snyan 3089495Snyan# Screen defaults and assumptions. 3189495Snyan 3289495Snyan.`ifdef' PC98 3389495Snyan .set SCR_MAT,0xe1 # Mode/attribute 3489495Snyan.else 3589495Snyan .set SCR_MAT,0x7 # Mode/attribute 3689495Snyan.endif 3789495Snyan .set SCR_COL,0x50 # Columns per row 3889495Snyan .set SCR_ROW,0x19 # Rows per screen 3989495Snyan 4089495Snyan# BIOS Data Area locations. 4189495Snyan 4289495Snyan.`ifdef' PC98 4389495Snyan .set BDA_POS,0x53e # Cursor position 4489495Snyan.else 4589495Snyan .set BDA_SCR,0x449 # Video mode 4689495Snyan .set BDA_POS,0x450 # Cursor position 4789495Snyan.endif 4889495Snyan 4989495Snyan .globl _(crt_putchr) 5089495Snyan 5189495Snyan# void crt_putchr(int c) 5289495Snyan 5389495Snyan_(crt_putchr): movb 0x4(%esp,1),%al # Get character 5489495Snyan pusha # Save 5589495Snyan xorl %ecx,%ecx # Zero for loops 5689495Snyan movb $SCR_MAT,%ah # Mode/attribute 5789495Snyan movl $BDA_POS,%ebx # BDA pointer 5889495Snyan movw (%ebx),%dx # Cursor position 5989495Snyan.`ifdef' PC98 6089495Snyan movl $0xa0000,%edi 6189495Snyan.else 6289495Snyan movl $0xb8000,%edi # Regen buffer (color) 6389495Snyan cmpb %ah,BDA_SCR-BDA_POS(%ebx) # Mono mode? 6489495Snyan jne crt_putchr.1 # No 6589495Snyan xorw %di,%di # Regen buffer (mono) 6689495Snyan.endif 6789495Snyancrt_putchr.1: cmpb $0xa,%al # New line? 6889495Snyan je crt_putchr.2 # Yes 6989495Snyan.`ifdef' PC98 7089495Snyan movw %dx,%cx 7189495Snyan movb %al,(%edi,%ecx,1) # Write char 7289495Snyan addl $0x2000,%ecx 7389495Snyan movb %ah,(%edi,%ecx,1) # Write attr 7489495Snyan addw $0x02,%dx 7589495Snyan jmp putchr.3 7689495Snyanputchr.2: movw %dx,%ax 7789495Snyan movb $SCR_COL*2,%dl 7889495Snyan div %dl 7989495Snyan incb %al 8089495Snyan mul %dl 8189495Snyan movw %ax,%dx 8289495Snyanputchr.3: cmpw $SCR_ROW*SCR_COL*2,%dx 8389495Snyan.else 8489495Snyan xchgl %eax,%ecx # Save char 8589495Snyan movb $SCR_COL,%al # Columns per row 8689495Snyan mulb %dh # * row position 8789495Snyan addb %dl,%al # + column 8889495Snyan adcb $0x0,%ah # position 8989495Snyan shll %eax # * 2 9089495Snyan xchgl %eax,%ecx # Swap char, offset 9189495Snyan movw %ax,(%edi,%ecx,1) # Write attr:char 9289495Snyan incl %edx # Bump cursor 9389495Snyan cmpb $SCR_COL,%dl # Beyond row? 9489495Snyan jb crt_putchr.3 # No 9589495Snyancrt_putchr.2: xorb %dl,%dl # Zero column 9689495Snyan incb %dh # Bump row 9789495Snyancrt_putchr.3: cmpb $SCR_ROW,%dh # Beyond screen? 9889495Snyan.endif 9989495Snyan jb crt_putchr.4 # No 10089495Snyan leal 2*SCR_COL(%edi),%esi # New top line 10189495Snyan movw $(SCR_ROW-1)*SCR_COL/2,%cx # Words to move 10289495Snyan rep # Scroll 10389495Snyan movsl # screen 10489495Snyan movb $' ',%al # Space 10589495Snyan.`ifdef' PC98 10689495Snyan xorb %ah,%ah 10789495Snyan.endif 10889495Snyan movb $SCR_COL,%cl # Columns to clear 10989495Snyan rep # Clear 11089495Snyan stosw # line 11189495Snyan.`ifdef' PC98 11289495Snyan movw $(SCR_ROW-1)*SCR_COL*2,%dx 11389495Snyan.else 11489495Snyan movb $SCR_ROW-1,%dh # Bottom line 11589495Snyan.endif 11689495Snyancrt_putchr.4: movw %dx,(%ebx) # Update position 11789495Snyan popa # Restore 11889495Snyan ret # To caller 119