pm.c

gumstiz u-boot loader in linux

/****************************************************************************
*
*                   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.
*
*  ========================================================================
*
* Language:     ANSI C
* Environment:  *** TODO: ADD YOUR OS ENVIRONMENT NAME HERE ***
*
* Description:  Implementation for the OS Portability Manager Library, which
*               contains functions to implement OS specific services in a
*               generic, cross platform API. Porting the OS Portability
*               Manager library is the first step to porting any SciTech
*               products to a new platform.
*
****************************************************************************/

#include "pmapi.h"
#include "drvlib/os/os.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/* TODO: Include any OS specific headers here! */

/*--------------------------- Global variables ----------------------------*/

/* TODO: If you support access to the BIOS, the following VESABuf globals */
/*       keep track of a single VESA transfer buffer. If you don't support */
/*       access to the BIOS, remove these variables. */

static uint VESABuf_len = 1024;     /* Length of the VESABuf buffer     */
static void *VESABuf_ptr = NULL;    /* Near pointer to VESABuf          */
static uint VESABuf_rseg;           /* Real mode segment of VESABuf     */
static uint VESABuf_roff;           /* Real mode offset of VESABuf      */

static void (PMAPIP fatalErrorCleanup)(void) = NULL;

/*----------------------------- Implementation ----------------------------*/

/****************************************************************************
REMARKS:
Initialise the PM library.
****************************************************************************/
void PMAPI PM_init(void)
{
    /* TODO: Do any initialisation in here. This includes getting IOPL */
    /*       access for the process calling PM_init. This will get called */
    /*       more than once. */

    /* TODO: If you support the supplied MTRR register stuff (you need to */
    /*       be at ring 0 for this!), you should initialise it in here. */

/* MTRR_init(); */
}

/****************************************************************************
REMARKS:
Return the operating system type identifier.
****************************************************************************/
long PMAPI PM_getOSType(void)
{
    /* TODO: Change this to return the define for your OS from drvlib/os.h */
    return _OS_MYOS;
}

/****************************************************************************
REMARKS:
Return the runtime type identifier (always PM_386 for protected mode)
****************************************************************************/
int PMAPI PM_getModeType(void)
{ return PM_386; }

/****************************************************************************
REMARKS:
Add a file directory separator to the end of the filename.
****************************************************************************/
void PMAPI PM_backslash(
    char *s)
{
    uint pos = strlen(s);
    if (s[pos-1] != '/') {
	s[pos] = '/';
	s[pos+1] = '\0';
	}
}

/****************************************************************************
REMARKS:
Add a user defined PM_fatalError cleanup function.
****************************************************************************/
void PMAPI PM_setFatalErrorCleanup(
    void (PMAPIP cleanup)(void))
{
    fatalErrorCleanup = cleanup;
}

/****************************************************************************
REMARKS:
Report a fatal error condition and halt the program.
****************************************************************************/
void PMAPI PM_fatalError(
    const char *msg)
{
    /* TODO: If you are running in a GUI environment without a console, */
    /*       this needs to be changed to bring up a fatal error message */
    /*       box and terminate the program. */
    if (fatalErrorCleanup)
	fatalErrorCleanup();
    fprintf(stderr,"%s\n", msg);
    exit(1);
}

/****************************************************************************
REMARKS:
Exit handler to kill the VESA transfer buffer.
****************************************************************************/
static void ExitVBEBuf(void)
{
    /* TODO: If you do not have BIOS access, remove this function. */
    if (VESABuf_ptr)
	PM_freeRealSeg(VESABuf_ptr);
    VESABuf_ptr = 0;
}

/****************************************************************************
REMARKS:
Allocate the real mode VESA transfer buffer for communicating with the BIOS.
****************************************************************************/
void * PMAPI PM_getVESABuf(
    uint *len,
    uint *rseg,
    uint *roff)
{
    /* TODO: If you do not have BIOS access, simply delete the guts of */
    /*       this function and return NULL. */
    if (!VESABuf_ptr) {
	/* Allocate a global buffer for communicating with the VESA VBE */
	if ((VESABuf_ptr = PM_allocRealSeg(VESABuf_len, &VESABuf_rseg, &VESABuf_roff)) == NULL)
	    return NULL;
	atexit(ExitVBEBuf);
	}
    *len = VESABuf_len;
    *rseg = VESABuf_rseg;
    *roff = VESABuf_roff;
    return VESABuf_ptr;
}

/****************************************************************************
REMARKS:
Check if a key has been pressed.
****************************************************************************/
int PMAPI PM_kbhit(void)
{
    /* TODO: This function checks if a key is available to be read. This */
    /*       should be implemented, but is mostly used by the test programs */
    /*       these days. */
    return true;
}

/****************************************************************************
REMARKS:
Wait for and return the next keypress.
****************************************************************************/
int PMAPI PM_getch(void)
{
    /* TODO: This returns the ASCII code of the key pressed. This */
    /*       should be implemented, but is mostly used by the test programs */
    /*       these days. */
    return 0xD;
}

/****************************************************************************
REMARKS:
Open a fullscreen console mode for output.
****************************************************************************/
int PMAPI PM_openConsole(void)
{
    /* TODO: Opens up a fullscreen console for graphics output. If your */
    /*       console does not have graphics/text modes, this can be left */
    /*       empty. The main purpose of this is to disable console switching */
    /*       when in graphics modes if you can switch away from fullscreen */
    /*       consoles (if you want to allow switching, this can be done */
    /*       elsewhere with a full save/restore state of the graphics mode). */
    return 0;
}

/****************************************************************************
REMARKS:
Return the size of the state buffer used to save the console state.
****************************************************************************/
int PMAPI PM_getConsoleStateSize(void)
{
    /* TODO: Returns the size of the console state buffer used to save the */
    /*       state of the console before going into graphics mode. This is */
    /*       used to restore the console back to normal when we are done. */
    return 1;
}

/****************************************************************************
REMARKS:
Save the state of the console into the state buffer.
****************************************************************************/
void PMAPI PM_saveConsoleState(
    void *stateBuf,
    int console_id)
{
    /* TODO: Saves the state of the console into the state buffer. This is */
    /*       used to restore the console back to normal when we are done. */
    /*       We will always restore 80x25 text mode after being in graphics */
    /*       mode, so if restoring text mode is all you need to do this can */
    /*       be left empty. */
}

/****************************************************************************
REMARKS:
Restore the state of the console from the state buffer.
****************************************************************************/
void PMAPI PM_restoreConsoleState(
    const void *stateBuf,
    int console_id)
{
    /* TODO: Restore the state of the console from the state buffer. This is */
    /*       used to restore the console back to normal when we are done. */
    /*       We will always restore 80x25 text mode after being in graphics */
    /*       mode, so if restoring text mode is all you need to do this can */
    /*       be left empty. */
}

/****************************************************************************
REMARKS:
Close the console and return to non-fullscreen console mode.
****************************************************************************/
void PMAPI PM_closeConsole(
    int console_id)
{
    /* TODO: Close the console when we are done, going back to text mode. */
}

/****************************************************************************
REMARKS:
Set the location of the OS console cursor.
****************************************************************************/
void PM_setOSCursorLocation(
    int x,
    int y)
{
    /* TODO: Set the OS console cursor location to the new value. This is */
    /*       generally used for new OS ports (used mostly for DOS). */
}

/****************************************************************************
REMARKS:
Set the width of the OS console.
****************************************************************************/
void PM_setOSScreenWidth(
    int width,
    int height)
{
    /* TODO: Set the OS console screen width. This is generally unused for */
    /*       new OS ports. */
}

/****************************************************************************
REMARKS:
Set the real time clock handler (used for software stereo modes).
****************************************************************************/
ibool PMAPI PM_setRealTimeClockHandler(
    PM_intHandler ih,
    int frequency)
{
    /* TODO: Install a real time clock interrupt handler. Normally this */
    /*       will not be supported from most OS'es in user land, so an */
    /*       alternative mechanism is needed to enable software stereo. */
    /*       Hence leave this unimplemented unless you have a high priority */
    /*       mechanism to call the 32-bit callback when the real time clock */
    /*       interrupt fires. */
    return false;
}

/****************************************************************************
REMARKS:
Set the real time clock frequency (for stereo modes).
****************************************************************************/
void PMAPI PM_setRealTimeClockFrequency(
    int frequency)
{
    /* TODO: Set the real time clock interrupt frequency. Used for stereo */
    /*       LC shutter glasses when doing software stereo. Usually sets */
    /*       the frequency to around 2048 Hz. */
}

/****************************************************************************
REMARKS:
Restore the original real time clock handler.
****************************************************************************/
void PMAPI PM_restoreRealTimeClockHandler(void)
{
    /* TODO: Restores the real time clock handler. */
}

/****************************************************************************
REMARKS:
Return the current operating system path or working directory.
****************************************************************************/
char * PMAPI PM_getCurrentPath(
    char *path,
    int maxLen)
{
    return getcwd(path,maxLen);