/*
 * Abstraction of the AGP GART interface.
 *
 * This version is for both Linux and FreeBSD.
 *
 * Copyright © 2000-2001 Nokia Home Communications
 * Copyright © 2000 VA Linux Systems, Inc.
 
All rights reserved.

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, and/or sell copies of the Software, and to permit persons
to whom the Software is furnished to do so, provided that the above
copyright notice(s) and this permission notice appear in all copies of
the Software and that both the above copyright notice(s) and this
permission notice appear in supporting documentation.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY
SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER
RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

Except as contained in this notice, the name of a copyright holder
shall not be used in advertising or otherwise to promote the sale, use
or other dealings in this Software without prior written authorization
of the copyright holder.

 */

/* $XFree86: xc/programs/Xserver/hw/kdrive/linux/agp.c,v 1.1 2001/03/30 02:18:41 keithp Exp $ */

/*
 * Author: Pontus Lidman <pontus.lidman@nokia.com> (adaption to KDrive) and others
 */

#include <X11/X.h>

#include <X11/Xdefs.h>
#include <X11/Xmd.h>

#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>

#include "agp.h"

#if defined(linux)
#include <asm/ioctl.h>

#include "../../xfree86/os-support/linux/agpgart.h"

#elif defined(__FreeBSD__)
#include <sys/ioctl.h>
#include <sys/agpio.h>
#endif

#ifndef AGP_DEVICE
#define AGP_DEVICE		"/dev/agpgart"
#endif
/* AGP page size is independent of the host page size. */
#ifndef AGP_PAGE_SIZE
#define AGP_PAGE_SIZE		4096
#endif
#define AGPGART_MAJOR_VERSION	0
#define AGPGART_MINOR_VERSION	99

static int gartFd = -1;
static int acquiredScreen = -1;

/*
 * Open /dev/agpgart.  Keep it open until server exit.
 */

static Bool
GARTInit()
{
	static Bool initDone = FALSE;
	struct _agp_info agpinf;

	if (initDone)
		return (gartFd != -1);

	initDone = TRUE;

	if (gartFd == -1)
		gartFd = open(AGP_DEVICE, O_RDWR, 0);
	else
		return FALSE;

	if (gartFd == -1) {
#ifdef ERRORS
            fprintf(stderr, "Unable to open " AGP_DEVICE " (%s)\n",
                    strerror(errno)); 
#endif
            return FALSE;
	}

	KdAcquireGART(-1);
	/* Check the kernel driver version. */
	if (ioctl(gartFd, AGPIOC_INFO, &agpinf) != 0) {
#ifdef ERRORS
            fprintf(stderr, "GARTInit: AGPIOC_INFO failed (%s)\n", 
                    strerror(errno)); 
#endif
            close(gartFd);
            gartFd = -1;
            return FALSE;
	}
	KdReleaseGART(-1);

#if defined(linux)
	/* Should this look for version >= rather than version == ? */
	if (agpinf.version.major != AGPGART_MAJOR_VERSION &&
	    agpinf.version.minor != AGPGART_MINOR_VERSION) {
#ifdef ERRORS
            fprintf(stderr, 
                    "Kernel agpgart driver version is not current" 
                    " (%d.%d vs %d.%d)\n", 
                    agpinf.version.major, agpinf.version.minor, 
                    AGPGART_MAJOR_VERSION, AGPGART_MINOR_VERSION); 
#endif
            close(gartFd);
            gartFd = -1;
            return FALSE;
	}
#endif
	
	return TRUE;
}

Bool
KdAgpGARTSupported()
{
	return GARTInit();
}

AgpInfoPtr
KdGetAGPInfo(int screenNum)
{
	struct _agp_info agpinf;
	AgpInfoPtr info;

	if (!GARTInit())
		return NULL;


	if ((info = calloc(sizeof(AgpInfo), 1)) == NULL) {
#ifdef ERRORS
            fprintf(stderr, "Failed to allocate AgpInfo\n"); 
#endif
            return NULL;
	}

	if (ioctl(gartFd, AGPIOC_INFO, &agpinf) != 0) {
#ifdef ERRORS
            fprintf(stderr, 
                    "xf86GetAGPInfo: AGPIOC_INFO failed (%s)\n", 
                    strerror(errno)); 
#endif
            return NULL;
	}

	info->bridgeId = agpinf.bridge_id;
	info->agpMode = agpinf.agp_mode;
	info->base = agpinf.aper_base;
	info->size = agpinf.aper_size;
	info->totalPages = agpinf.pg_total;
	info->systemPages = agpinf.pg_system;
	info->usedPages = agpinf.pg_used;

	return info;
}

/*
 * XXX If multiple screens can acquire the GART, should we have a reference
 * count instead of using acquiredScreen?
 */

Bool
KdAcquireGART(int screenNum)
{
    if (screenNum != -1 && !GARTInit())
        return FALSE;
    
    if (screenNum == -1 || acquiredScreen != screenNum) {
        if (ioctl(gartFd, AGPIOC_ACQUIRE, 0) != 0) {
#ifdef ERRORS
            fprintf(stderr, 
                    "AGPIOC_ACQUIRE failed (%s)\n", 
                    strerror(errno)); 
#endif
            return FALSE;
        }
        acquiredScreen = screenNum;
    }
    
    return TRUE;
}

Bool
KdReleaseGART(int screenNum)
{
	if (screenNum != -1 && !GARTInit())
		return FALSE;

	if (acquiredScreen == screenNum) {
		if (ioctl(gartFd, AGPIOC_RELEASE, 0) != 0) {
#ifdef ERRORS
 			fprintf(stderr,
 				   "AGPIOC_RELEASE failed (%s)\n",
 				   strerror(errno)); 
#endif
			return FALSE;
		}
		acquiredScreen = -1;
		return TRUE;
	}
	return FALSE;
}

int
KdAllocateGARTMemory(int screenNum, unsigned long size, int type,
			unsigned long *physical)
{
	struct _agp_allocate alloc;
	int pages;

	/*
	 * Allocates "size" bytes of GART memory (rounds up to the next
	 * page multiple) or type "type".  A handle (key) for the allocated
	 * memory is returned.  On error, the return value is -1.
	 */

	if (!GARTInit() || acquiredScreen != screenNum)
		return -1;

	pages = (size / AGP_PAGE_SIZE);
	if (size % AGP_PAGE_SIZE != 0)
		pages++;

	/* XXX check for pages == 0? */

	alloc.pg_count = pages;
	alloc.type = type;

	if (ioctl(gartFd, AGPIOC_ALLOCATE, &alloc) != 0) {
#ifdef ERRORS
            fprintf(stderr, "KdAllocateGARTMemory: " 
                    "allocation of %d pages failed\n\t(%s)\n", pages, 
                    strerror(errno)); 
#endif
		return -1;
	}

	if (physical)
		*physical = alloc.physical;

	return alloc.key;
}


/* Bind GART memory with "key" at "offset" */
Bool
KdBindGARTMemory(int screenNum, int key, unsigned long offset)
{
	struct _agp_bind bind;
	int pageOffset;

	if (!GARTInit() || acquiredScreen != screenNum)
		return FALSE;

	if (acquiredScreen != screenNum) {
#ifdef ERRORS
            fprintf(stderr, 
                    "AGP not acquired by this screen\n"); 
#endif
            return FALSE;
	}

	if (offset % AGP_PAGE_SIZE != 0) {
#ifdef ERRORS
            fprintf(stderr, "KdBindGARTMemory: " 
                    "offset (0x%lx) is not page-aligned (%d)\n", 
                    offset, AGP_PAGE_SIZE); 
#endif
            return FALSE;
	}
	pageOffset = offset / AGP_PAGE_SIZE;

	bind.pg_start = pageOffset;
	bind.key = key;

	if (ioctl(gartFd, AGPIOC_BIND, &bind) != 0) {
#ifdef ERRORS
		fprintf(stderr, "KdBindGARTMemory: "
                        "binding of gart memory with key %d\n"
                        "\tat offset 0x%lx failed (%s)\n",
                        key, offset, strerror(errno));
#endif
		return FALSE;
	}

	return TRUE;
}


/* Unbind GART memory with "key" */
Bool
KdUnbindGARTMemory(int screenNum, int key)
{
	struct _agp_unbind unbind;

	if (!GARTInit() || acquiredScreen != screenNum)
		return FALSE;

	if (acquiredScreen != screenNum) {
#ifdef ERRORS
		fprintf(stderr,
			   "AGP not acquired by this screen\n");
#endif
		return FALSE;
	}

	unbind.priority = 0;
	unbind.key = key;

	if (ioctl(gartFd, AGPIOC_UNBIND, &unbind) != 0) {
#ifdef ERRORS
		fprintf(stderr, "KdUnbindGARTMemory: "
			   "unbinding of gart memory with key %d "
			   "failed (%s)\n", key, strerror(errno));
#endif
		return FALSE;
	}

	return TRUE;
}


/* XXX Interface may change. */
Bool
KdEnableAGP(int screenNum, CARD32 mode)
{
	agp_setup setup;

	if (!GARTInit() || acquiredScreen != screenNum)
		return FALSE;

	setup.agp_mode = mode;
	if (ioctl(gartFd, AGPIOC_SETUP, &setup) != 0) {
#ifdef ERRORS
		fprintf(stderr, "KdEnableAGP: "
			   "AGPIOC_SETUP with mode %ld failed (%s)\n",
			   mode, strerror(errno));
#endif
		return FALSE;
	}

	return TRUE;
}

