| /**************************************************************************** |
| * |
| * SciTech OS Portability Manager Library |
| * |
| * ======================================================================== |
| * |
| * The contents of this file are subject to the SciTech MGL Public |
| * License Version 1.0 (the "License"); you may not use this file |
| * except in compliance with the License. You may obtain a copy of |
| * the License at http://www.scitechsoft.com/mgl-license.txt |
| * |
| * Software distributed under the License is distributed on an |
| * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or |
| * implied. See the License for the specific language governing |
| * rights and limitations under the License. |
| * |
| * The Original Code is Copyright (C) 1991-1998 SciTech Software, Inc. |
| * |
| * The Initial Developer of the Original Code is SciTech Software, Inc. |
| * All Rights Reserved. |
| * |
| * ======================================================================== |
| * |
| * Portions copyright (C) Josh Vanderhoof |
| * |
| * Language: ANSI C |
| * Environment: Any |
| * |
| * Description: Functions to save and restore the VGA hardware state. |
| * |
| ****************************************************************************/ |
| |
| #include "pmapi.h" |
| #if defined(__WIN32_VXD__) || defined(__NT_DRIVER__) |
| #include "sdd/sddhelp.h" |
| #else |
| #include <string.h> |
| #endif |
| |
| /*--------------------------- Global variables ----------------------------*/ |
| |
| /* VGA index register ports */ |
| #define CRT_I 0x3D4 /* CRT Controller Index */ |
| #define ATT_IW 0x3C0 /* Attribute Controller Index & Data */ |
| #define GRA_I 0x3CE /* Graphics Controller Index */ |
| #define SEQ_I 0x3C4 /* Sequencer Index */ |
| |
| /* VGA data register ports */ |
| #define CRT_D 0x3D5 /* CRT Controller Data Register */ |
| #define ATT_R 0x3C1 /* Attribute Controller Data Read Register */ |
| #define GRA_D 0x3CF /* Graphics Controller Data Register */ |
| #define SEQ_D 0x3C5 /* Sequencer Data Register */ |
| #define MIS_R 0x3CC /* Misc Output Read Register */ |
| #define MIS_W 0x3C2 /* Misc Output Write Register */ |
| #define IS1_R 0x3DA /* Input Status Register 1 */ |
| #define PEL_IW 0x3C8 /* PEL Write Index */ |
| #define PEL_IR 0x3C7 /* PEL Read Index */ |
| #define PEL_D 0x3C9 /* PEL Data Register */ |
| |
| /* standard VGA indexes max counts */ |
| #define CRT_C 24 /* 24 CRT Controller Registers */ |
| #define ATT_C 21 /* 21 Attribute Controller Registers */ |
| #define GRA_C 9 /* 9 Graphics Controller Registers */ |
| #define SEQ_C 5 /* 5 Sequencer Registers */ |
| #define MIS_C 1 /* 1 Misc Output Register */ |
| #define PAL_C 768 /* 768 Palette Registers */ |
| #define FONT_C 8192 /* Total size of character generator RAM */ |
| |
| /* VGA registers saving indexes */ |
| #define CRT 0 /* CRT Controller Registers start */ |
| #define ATT (CRT+CRT_C) /* Attribute Controller Registers start */ |
| #define GRA (ATT+ATT_C) /* Graphics Controller Registers start */ |
| #define SEQ (GRA+GRA_C) /* Sequencer Registers */ |
| #define MIS (SEQ+SEQ_C) /* General Registers */ |
| #define PAL (MIS+MIS_C) /* VGA Palette Registers */ |
| #define FONT (PAL+PAL_C) /* VGA font data */ |
| |
| /* Macros for port I/O with arguments reversed */ |
| |
| #define _port_out(v,p) PM_outpb(p,(uchar)(v)) |
| #define _port_in(p) PM_inpb(p) |
| |
| /*----------------------------- Implementation ----------------------------*/ |
| |
| /**************************************************************************** |
| REMARKS: |
| Returns the size of the VGA state buffer. |
| ****************************************************************************/ |
| int PMAPI PM_getVGAStateSize(void) |
| { |
| return CRT_C + ATT_C + GRA_C + SEQ_C + MIS_C + PAL_C + FONT_C; |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Delay for a short period of time. |
| ****************************************************************************/ |
| static void vga_delay(void) |
| { |
| int i; |
| |
| /* For the loop here we program the POST register. The length of this |
| * delay is dependant only on ISA bus speed, but it is enough for |
| * what we need. |
| */ |
| for (i = 0; i <= 10; i++) |
| PM_outpb(0x80, 0); |
| } |
| |
| /**************************************************************************** |
| PARAMETERS: |
| port - I/O port to read value from |
| index - Port index to read |
| |
| RETURNS: |
| Byte read from 'port' register 'index'. |
| ****************************************************************************/ |
| static ushort vga_rdinx( |
| ushort port, |
| ushort index) |
| { |
| PM_outpb(port,(uchar)index); |
| return PM_inpb(port+1); |
| } |
| |
| /**************************************************************************** |
| PARAMETERS: |
| port - I/O port to write to |
| index - Port index to write |
| value - Byte to write to port |
| |
| REMARKS: |
| Writes a byte value to the 'port' register 'index'. |
| ****************************************************************************/ |
| static void vga_wrinx( |
| ushort port, |
| ushort index, |
| ushort value) |
| { |
| PM_outpb(port,(uchar)index); |
| PM_outpb(port+1,(uchar)value); |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Save the color palette values |
| ****************************************************************************/ |
| static void vga_savepalette( |
| uchar *pal) |
| { |
| int i; |
| |
| _port_out(0, PEL_IR); |
| for (i = 0; i < 768; i++) { |
| vga_delay(); |
| *pal++ = _port_in(PEL_D); |
| } |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Restore the color palette values |
| ****************************************************************************/ |
| static void vga_restorepalette( |
| const uchar *pal) |
| { |
| int i; |
| |
| /* restore saved palette */ |
| _port_out(0, PEL_IW); |
| for (i = 0; i < 768; i++) { |
| vga_delay(); |
| _port_out(*pal++, PEL_D); |
| } |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Read the font data from the VGA character generator RAM |
| ****************************************************************************/ |
| static void vga_saveFont( |
| uchar *data) |
| { |
| uchar *A0000Ptr = PM_getA0000Pointer(); |
| uchar save[7]; |
| |
| /* Enable access to character generator RAM */ |
| save[0] = (uchar)vga_rdinx(SEQ_I,0x00); |
| save[1] = (uchar)vga_rdinx(SEQ_I,0x02); |
| save[2] = (uchar)vga_rdinx(SEQ_I,0x04); |
| save[3] = (uchar)vga_rdinx(SEQ_I,0x00); |
| save[4] = (uchar)vga_rdinx(GRA_I,0x04); |
| save[5] = (uchar)vga_rdinx(GRA_I,0x05); |
| save[6] = (uchar)vga_rdinx(GRA_I,0x06); |
| vga_wrinx(SEQ_I,0x00,0x01); |
| vga_wrinx(SEQ_I,0x02,0x04); |
| vga_wrinx(SEQ_I,0x04,0x07); |
| vga_wrinx(SEQ_I,0x00,0x03); |
| vga_wrinx(GRA_I,0x04,0x02); |
| vga_wrinx(GRA_I,0x05,0x00); |
| vga_wrinx(GRA_I,0x06,0x00); |
| |
| /* Copy character generator RAM */ |
| memcpy(data,A0000Ptr,FONT_C); |
| |
| /* Restore VGA state */ |
| vga_wrinx(SEQ_I,0x00,save[0]); |
| vga_wrinx(SEQ_I,0x02,save[1]); |
| vga_wrinx(SEQ_I,0x04,save[2]); |
| vga_wrinx(SEQ_I,0x00,save[3]); |
| vga_wrinx(GRA_I,0x04,save[4]); |
| vga_wrinx(GRA_I,0x05,save[5]); |
| vga_wrinx(GRA_I,0x06,save[6]); |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Downloads the font data to the VGA character generator RAM |
| ****************************************************************************/ |
| static void vga_restoreFont( |
| const uchar *data) |
| { |
| uchar *A0000Ptr = PM_getA0000Pointer(); |
| |
| /* Enable access to character generator RAM */ |
| vga_wrinx(SEQ_I,0x00,0x01); |
| vga_wrinx(SEQ_I,0x02,0x04); |
| vga_wrinx(SEQ_I,0x04,0x07); |
| vga_wrinx(SEQ_I,0x00,0x03); |
| vga_wrinx(GRA_I,0x04,0x02); |
| vga_wrinx(GRA_I,0x05,0x00); |
| vga_wrinx(GRA_I,0x06,0x00); |
| |
| /* Copy font back to character generator RAM */ |
| memcpy(A0000Ptr,data,FONT_C); |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Save the state of all VGA compatible registers |
| ****************************************************************************/ |
| void PMAPI PM_saveVGAState( |
| void *stateBuf) |
| { |
| uchar *regs = stateBuf; |
| int i; |
| |
| /* Save state of VGA registers */ |
| for (i = 0; i < CRT_C; i++) { |
| _port_out(i, CRT_I); |
| regs[CRT + i] = _port_in(CRT_D); |
| } |
| for (i = 0; i < ATT_C; i++) { |
| _port_in(IS1_R); |
| vga_delay(); |
| _port_out(i, ATT_IW); |
| vga_delay(); |
| regs[ATT + i] = _port_in(ATT_R); |
| vga_delay(); |
| } |
| for (i = 0; i < GRA_C; i++) { |
| _port_out(i, GRA_I); |
| regs[GRA + i] = _port_in(GRA_D); |
| } |
| for (i = 0; i < SEQ_C; i++) { |
| _port_out(i, SEQ_I); |
| regs[SEQ + i] = _port_in(SEQ_D); |
| } |
| regs[MIS] = _port_in(MIS_R); |
| |
| /* Save the VGA palette values */ |
| vga_savepalette(®s[PAL]); |
| |
| /* Save the VGA character generator RAM */ |
| vga_saveFont(®s[FONT]); |
| |
| /* Turn the VGA display back on */ |
| PM_vgaUnblankDisplay(); |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Retore the state of all VGA compatible registers |
| ****************************************************************************/ |
| void PMAPI PM_restoreVGAState( |
| const void *stateBuf) |
| { |
| const uchar *regs = stateBuf; |
| int i; |
| |
| /* Blank the display before we start the restore */ |
| PM_vgaBlankDisplay(); |
| |
| /* Restore the VGA character generator RAM */ |
| vga_restoreFont(®s[FONT]); |
| |
| /* Restore the VGA palette values */ |
| vga_restorepalette(®s[PAL]); |
| |
| /* Restore the state of the VGA compatible registers */ |
| _port_out(regs[MIS], MIS_W); |
| |
| /* Delay to allow clock change to settle */ |
| for (i = 0; i < 10; i++) |
| vga_delay(); |
| |
| /* Synchronous reset on */ |
| _port_out(0x00,SEQ_I); |
| _port_out(0x01,SEQ_D); |
| |
| /* Write seqeuencer registers */ |
| _port_out(1, SEQ_I); |
| _port_out(regs[SEQ + 1] | 0x20, SEQ_D); |
| for (i = 2; i < SEQ_C; i++) { |
| _port_out(i, SEQ_I); |
| _port_out(regs[SEQ + i], SEQ_D); |
| } |
| |
| /* Synchronous reset off */ |
| _port_out(0x00,SEQ_I); |
| _port_out(0x03,SEQ_D); |
| |
| /* Deprotect CRT registers 0-7 and write CRTC */ |
| _port_out(0x11, CRT_I); |
| _port_out(_port_in(CRT_D) & 0x7F, CRT_D); |
| for (i = 0; i < CRT_C; i++) { |
| _port_out(i, CRT_I); |
| _port_out(regs[CRT + i], CRT_D); |
| } |
| for (i = 0; i < GRA_C; i++) { |
| _port_out(i, GRA_I); |
| _port_out(regs[GRA + i], GRA_D); |
| } |
| for (i = 0; i < ATT_C; i++) { |
| _port_in(IS1_R); /* reset flip-flop */ |
| vga_delay(); |
| _port_out(i, ATT_IW); |
| vga_delay(); |
| _port_out(regs[ATT + i], ATT_IW); |
| vga_delay(); |
| } |
| |
| /* Ensure the VGA screen is turned on */ |
| PM_vgaUnblankDisplay(); |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Disables the VGA display for screen output making it blank. |
| ****************************************************************************/ |
| void PMAPI PM_vgaBlankDisplay(void) |
| { |
| /* Turn screen off */ |
| _port_out(0x01, SEQ_I); |
| _port_out(_port_in(SEQ_D) | 0x20, SEQ_D); |
| |
| /* Disable video output */ |
| _port_in(IS1_R); |
| vga_delay(); |
| _port_out(0x00, ATT_IW); |
| } |
| |
| /**************************************************************************** |
| REMARKS: |
| Enables the VGA display for screen output. |
| ****************************************************************************/ |
| void PMAPI PM_vgaUnblankDisplay(void) |
| { |
| /* Turn screen back on */ |
| _port_out(0x01, SEQ_I); |
| _port_out(_port_in(SEQ_D) & 0xDF, SEQ_D); |
| |
| /* Enable video output */ |
| _port_in(IS1_R); |
| vga_delay(); |
| _port_out(0x20, ATT_IW); |
| } |
